Ultrasound Guidance – Selected Indications

Number: 0952

Table Of Contents

Policy
Applicable CPT / HCPCS / ICD-10 Codes
Background
References


Policy

Scope of Policy

This Clinical Policy Bulletin addresses ultrasound guidance for selected indications.

  1. Medical Necessity

    Aetna considers ultrasound (US) guidance medically necessary for the following procedures (not an all-inclusive list):

    • Adductor canal nerve block
    • Arterial line placement
    • Axillary brachial plexus nerve block
    • Baker's cyst, after failure of unguided procedure
    • Breast abscess or cyst aspiration, if it is nonpalpable or loculated
    • Breast mass biopsy (see CPB 0269 - Breast Biopsy Procedures)
    • C5-C7 interscalene nerve block
    • Carpal tunnel injection
    • Carpal tunnel release
    • Central venous access (internal jugular, femoral)
    • Chest wall seroma aspiration
    • De Quervain tendinopathy, after failure of unguided procedure
    • Elbow joint injection or aspiration, after failure of unguided procedure 
    • Embryo transfer (see CPB 0327 - Infertility)
    • Endovenous laser ablation of the saphenous vein (ELAS) (see CPB 0050 - Varicose Veins)
    • Fascia iliaca block for the management of post-operative pain following hip and knee surgeries, and repair of femur fracture
    • Femoral nerve block for post-operative knee pain
    • Filling of implantable intrathecal pump reservoir (when reservoir port is difficult to identify, or if there is obstruction to performing a non-US refill)
    • Fine-needle aspiration for biopsy of neck mass if the lesion is not palpable, or if the initial palpation-guided biopsy was unsuccessful
    • Hepatic mass biopsy
    • Hip joint injection or aspiration
    • Iliohypogastric nerve block
    • Ilioinguinal nerve block
    • Infraclavicular nerve block for surgery of the distal arm and hand
    • Intercostobrachial nerve block
    • Inter-digital neuroma injection
    • Interscalene nerve block (including for shoulder dislocation reduction)
    • Intraabdominal or intrapelvic mass biopsy
    • Intrathecal drug delivery
    • IPACK nerve block for pain control after anterior cruciate ligament (ACL) repair or total knee arthroplasty
    • Ischial bursa and gluteus medius injection
    • Lateral femoral cutaneous nerve block for meralgia paresthetica (lateral femoral cutaneous nerve entrapment) (see CPB 0863 - Nerve Blocks)
    • Liver cyst aspiration
    • Long head of the biceps injection for the treatment of tendinosis of the biceps
    • Lumbar puncture (see CPB 0628 - Spinal Ultrasound)
    • Metacarpophalangeal joint injection or aspiration
    • Metatarsophalangeal joint injection or aspiration
    • Needle placement, lavage, and debridement of calcific tendinosis of the shoulder
    • Nephrocutaneous access
    • Pancreatic mass biopsy
    • Pectoral nerve blocks (PECS I and PECS II) for post-operative pain control after breast surgery / sternotomy for cardiac surgery
    • Pectoralis minor tendon sheath injection
    • Pectoralis nerve block (PEC 1 and PEC 2) for the management of post-operative pain following mastectomy
    • Phlegmonous fluid aspiration at any spinal segment (cervical, thoracic, lumbar, or sacral)
    • Piriformis ligament injection
    • Piriformis muscle injection
    • Placement of vena caval filter (see CPB 0382 - Intravascular Ultrasound)
    • Placement of intracoronary endoluminal devices (see CPB 0382 - Intravascular Ultrasound)
    • Popliteal nerve block
    • Posterior glenohumeral (GH) joint injection or aspiration, after failure of unguided procedure
    • Prostate biopsy for prosate nodule or elevated PSA (see CPB 0001 - Transrectal Ultrasound)
    • Pudendal nerve block for post-operative pain control after hypospadias surgery
    • Pulmonary or thoracic mass biopsy
    • Quadratus lumborum nerve block for post-operative pain control after abdominal surgery
    • Radiofrequency endovenous occlusion (VNUS) (see CPB 0050 - Varicose Veins)
    • Rectus sheath block and pecto-intercostal fascial block following cardiac surgery (e.g., aortic valve replacement)
    • Saphenous nerve block
    • Scapular thoracic bursitis injection
    • Sciatic nerve block
    • Serratus plane block for the management of post-operative pain following breast surgery or thoracotomy
    • Steroid injection into the gluteus maximus tendon 
    • Subacromial bursal injection or aspiration, after failure of unguided procedure
    • Subgluteal bursal injection or aspiration, after failure of unguided procedure
    • Subpectoral nerve block (parasternal T2 to T6 intercostal block) for postoperative pain control 
    • Subtalar joint injection or aspiration
    • Supraclavicular nerve block for primary regional anesthesia during surgeries, and post-operative pain control
    • Tibiotalar joint injection or aspiration, after failure of unguided procedure
    • Thyroid nodule biopsy
    • Transverse abdominis plane (TAP)-block for the management of post-operative pain following abdominal surgery
    • Wrist (radiocarpal) joint injection or aspiration, after failure of unguided procedure.
  2. Experimental, Investigational, or Unproven

    Aetna considers US guidance of no proven benefit for the following procedures (not an all-inclusive list):

    • Abductor digiti minimi injection
    • Acromioclavicular joint injection
    • Adductor brevis tendon injection
    • Adductor longus tendon injection
    • Ankle bursa injection 
    • Anterior medial ankle joint and tibialis posterior tendon sheath injection for foot pain
    • Anterior scalene/brachial plexus block for chronic pain
    • Aspiration of cyst(s) located in the inferolateral coccyx/sacral region
    • Aspiration of hematoma of the gastrocnemius
    • Aspiration of plunging ranula in the submandibular region
    • Botulinum toxin injection for cervical dystonia, limb and paraspinal spasticity, migraine, or spasmodic torticollis
    • Calcaneal/retrocalcaneal bursa injection
    • Carpometacarpal (CMC) joint injection
    • Calcified medial collateral ligament injection
    • Cervical aponeurosis injection
    • Clavi-pectoral fascial plane block
    • Collection of fluid for culture from the post-femoropopliteal bypass graft site
    • Costochondral joint
    • Deep peroneal nerve injection for peroneal neuritis
    • Diagnostic inguinal lymphangiography
    • Dorsal compartments of the wrist injection
    • Dorsal scapular nerve block
    • Endovascular treatment of subclavian artery disease (see CPB 0382 - Intravascular Ultrasound)
    • Epidural injections, including the transforaminal approach (see CPB 0016 - Back Pain - Invasive Procedures)
    • Erector spinae plane (ESP) block for the management of post-operative pain (see CPB 0863 - Nerve Blocks)
    • Extensor carpi ulnaris tendon injection
    • Facet joint injections (see CPB 0016 - Back Pain - Invasive Procedures)
    • Flexor tendon injection
    • Foot/heel injection for adventitious bursitis/capsulitis
    • Ganglion cyst injection of the wrist/wrist injection
    • Ganglion cyst injection or aspiration of of the ankle, finger, shoulder, or tarsometatarsal joint
    • Gluteal nerve injection
    • Gluteal tendon sheath injections for hip and/or low back pain
    • Gluteus medius tendon injecton
    • Hamstring tendon injeciton
    • Hematoma of thigh aspiration
    • Hematoma of shoulder aspiration
    • Hydrodissection of the dorsal scapular nerve and middle/inferior trapezius, rhomboids for peripheral nerve entrapment/shoulder pain
    • Hydrodissection of the Hoffa's fat pad (infra-patellar fat pad), paratenon of the patellar tendon, and psoas tendon
    • Hydrodissection of the infrapatellar saphenous nerve, or scar tissue at the trapezius tendon region
    • Identification and aspiration of hematomas following great saphenous veins vein surgery
    • Iliopsoas bursa injection
    • Iliopsoas tendon / tendon sheath injection
    • Iliotibial band bursa injection
    • Iliotibial (IT) band hydrodissection / IT band injection for IT band pain
    • Inguinal subcutaneous fluid aspiration
    • Intercostal nerve block
    • Inter-metatarsal bursa injection
    • Intraarticular injection for the management of shoulder impingement/pain
    • Ischial bursa injection for ischial bursitis
    • Ischial tuberosity peritendinous injection
    • Knee joint (except in morbidly obese individuals (BMI > 40))
    • Knot of Henry injection
    • Lateral epicondylitis injection
    • Lateral femoral cutaneous nerve block for the treatment of post-operative pain after total hip arthroplasty
    • Lateral pericapsular nerve group (PENG) nerve block during total hip arthroplasty
    • Latissimus dorsi injection 
    • Lavage of the shoulder joint
    • Ligament sheath injections
    • Lumbar erector fascia injection
    • Lumbar plexus block with hydrodissection
    • Medial calcaneal nerve sheath injection
    • Median nerve block
    • Metatarsophalangeal and/or metatarsal cuneiform joint injection for the treatment of plantar fibromatosis (Ledderhose disease)
    • Multifidus lumborum injection for the treatment of low back pain
    • Myositis ossificans injection
    • Needle aspiration or injection of ganglion cyst of metatarsophalangeal (MTP) joint
    • Needle placement during aortography
    • Nuchal ligament and supraspinous ligament injection
    • Occipital nerve block (see CPB 0863 - Nerve Blocks)
    • Os trigonum syndrome injection
    • Paravertebral nerve block for the following: after hip arthroplasty, during rib plate removal, periacetabular osteotomy and diagnostic hip arthroscopy, and post-operative pain management
    • Pectineus tendon injection
    • Percutaneous bursectomy of the pretibial tubercle bursa
    • Percutaneous tenotomy of the gluteus medius tendon for the treatment of hip tendinopathy
    • Perineal nerve block for spastic pelvic floor syndrome and pudendal neuralgia
    • Peritendon injection for the treatment of Achilles tendinopathy (including Kager’s fat pad, also known as pre-Achilles or pre-calcaneal fat pad)
    • Peroneal tendon sheath injection
    • Pes anserine bursa injection
    • Plantar fasciitis injections
    • Posterior tibial nerve block for plantar fasciitis
    • Pre-patellar bursa injection
    • Psoas tendon injection
    • Pudendal nerve block for the treatment of vulvodynia
    • Quadraceps tendon injection
    • Radial nerve block for post-operative pain management
    • Rectus abdominus muscle infiltration for palliative treatment of abdominal wall pain
    • Retinaculum of knee injection
    • Sacroiliac joint injection (see CPB 0016 - Back Pain - Invasive Procedures)
    • Saphenous vein access
    • Scapholunate ligament injection
    • Scar tissue injection after Dupuytren's cord excision surgery
    • Sclerotherapy for varicose veins (see CPB 0050 - Varicose Veins)
    • Semimembranosus tendon insertion injection
    • Subacromial bursitis injection
    • Subcutaneous seroma aspiration
    • Subfascial cyst anterior to the proximal talofibular joint, aspiration
    • Superficial cervical plexus block for post-operative pain control after left trans-mastoid endolymphatic shunt, (y) 
    • Superficial radiation treatment of skin cancer
    • Superior cluneal nerve injections
    • Suprascapular nerve block
    • Tarsal tunnel injection
    • Tendon injection (other than those listed as medically necessary above)
    • Tendon scraping/neovessel ablation for Achilles tendinosis
    • Tenotomy for the treatment of lateral epicondylitis
    • Tibiofibular joint injection
    • Trigger finger injection/trigger finger release with or without hydrodissection
    • Trigger point injections (see CPB 0016 - Back Pain - Invasive Procedures)
    • Trochanteric bursa injections
    • Upper trapezius injection
    • Viscosupplement injections (see CPB 0179 - Viscosupplementation).
  3. Related Policies


Table:

CPT Codes / HCPCS Codes / ICD-10 Codes

Code Code Description

Ultrasonic guidance for needle placement:

CPT codes covered if selection criteria are met:

76942 Ultrasonic guidance for needle placement (eg, biopsy, aspiration, injection, localization device), imaging supervision and interpretation
76998 Ultrasonic guidance, intraoperative

CPT codes for procedures where 76942 and 76998 are covered if selection criteria are met: (not all inclusive):

Piriformis muscle injection, Popliteal nerve block, Serratus plane block, Infraclavicular nerve block, IPACK nerve block, needle placement, lavage, and debridement of calcific tendinosis of the shoulder, Pectoral nerve block (PECS 1 and PECS 2), Sub-gluteal bursa injection – no specific code
10004 Fine needle aspiration biopsy, without imaging guidance; each additional lesion (List separately in addition to code for primary procedure) [of neck mass]
10021      first lesion [of neck mass]
19000 Puncture aspiration of cyst of breast
19001      each additional cyst (List separately in addition to code for primary procedure)
20526 Injection, therapeutic (eg, local anesthetic, corticosteroid), carpal tunnel
20606 Arthrocentesis, aspiration and/or injection, intermediate joint or bursa (eg, temporomandibular, acromioclavicular, wrist, elbow or ankle, olecranon bursa); with ultrasound guidance, with permanent recording and reporting [scapular thoracic bursitis injection] [not covered for Iliopsoas bursa injection] [Not covered for ankle bursa injection] [Not covered for calcaneal/retrocalcaneal bursa injection] [Not covered for foot/heel injection for adventitious bursitis/capsulitis] [Not covered for tibiofibular joint injection][Not covered for anterior medial ankle joint injection]
20611 Arthrocentesis, aspiration and/or injection, major joint or bursa (eg, shoulder, hip, knee, subacromial bursa); with ultrasound guidance, with permanent recording and reporting [scapular thoracic bursitis injection] [not covered for Iliopsoas bursa injection] [not covered for trochanteric bursa injection] [Not covered for intraarticular injection for the management of shoulder impingement/pain] [Not covered for subacromial bursitis injection] [long head of the biceps injection] [ischial bursa and gluteus medius injection] [Not covered for ischial bursa injection for ischial bursitis] [Not covered for pre-patellar bursa injection]
21550 Biopsy, soft tissue of neck or thorax [of neck mass]
25000 Incision, extensor tendon sheath, wrist (eg, deQuervains disease)
27345 Excision of synovial cyst of popliteal space (eg, Baker's cyst)
31717 Catheterization with bronchial brush biopsy
32096 Thoracotomy, with diagnostic biopsy(ies) of lung infiltrate(s) (eg, wedge, incisional), unilateral
32097 Thoracotomy, with diagnostic biopsy(ies) of lung nodule(s) or mass(es) (eg, wedge, incisional), unilateral
32098 Thoracotomy, with biopsy(ies) of pleura
32400 Biopsy, pleura, percutaneous needle
32408 Core needle biopsy, lung or mediastinum, percutaneous, including imaging guidance, when performed
32607 Thoracoscopy; with diagnostic biopsy(ies) of lung infiltrate(s) (eg, wedge, incisional), unilateral
32608     with diagnostic biopsy(ies) of lung nodule(s) or mass(es) (eg, wedge, incisional), unilateral
32609     with biopsy(ies) of pleura
47000 Biopsy of liver, needle; percutaneous
+47001     when done for indicated purpose at time of other major procedure (List separately in addition to code for primary procedure)
47100 Biopsy of liver, wedge
48100 Biopsy of pancreas, open (eg, fine needle aspiration, needle core biopsy, wedge biopsy)
48102 Biopsy of pancreas, percutaneous needle
49180 Biopsy, abdominal or retroperitoneal mass, percutaneous needle
49321 Laparoscopy, surgical; with biopsy (single or multiple)
49405 Image-guided fluid collection drainage by catheter (eg, abscess, hematoma, seroma, lymphocele, cyst); visceral (eg, kidney, liver, spleen, lung/mediastinum), percutaneous
50040 - 50081 Incision, renal
50220 - 50240 Excision, renal
50384 - 50386 Introduction, renal
50390 - 50431, 50433, 50435 Other Introduction, renal
50541, 50543 - 50549 Laparoscopy, renal
50590 - 50593 Lithotripsy
54322 1-stage distal hypospadias repair (with or without chordee or circumcision); with simple meatal advancement (eg, Magpi, V-flap)
54324      with urethroplasty by local skin flaps (eg, flip-flap, prepucial flap)
54326      with urethroplasty by local skin flaps and mobilization of urethra
54328      with extensive dissection to correct chordee and urethroplasty with local skin flaps, skin graft patch, and/or island flap
54332 1-stage proximal penile or penoscrotal hypospadias repair requiring extensive dissection to correct chordee and urethroplasty by use of skin graft tube and/or island flap
54336 1-stage perineal hypospadias repair requiring extensive dissection to correct chordee and urethroplasty by use of skin graft tube and/or island flap
55700 Biopsy, prostate; needle or punch, single or multiple, any approach
55705     incisional, any approach
58974 Embryo transfer, intrauterine
58976 Gamete, zygote, or embryo intrafallopian transfer, any method
60100 Biopsy thyroid, percutaneous core needle
62268 Percutaneous aspiration, spinal cord cyst or syrinx
62270 Spinal puncture, lumbar, diagnostic
62272 Spinal puncture, therapeutic, for drainage of cerebrospinal fluid (by needle or catheter)
62329 Spinal puncture, therapeutic, for drainage of cerebrospinal fluid (by needle or catheter); with fluoroscopic or CT guidance
62350 Implantation, revision or repositioning of tunneled intrathecal or epidural catheter, for long-term medication administration via an external pump or implantable reservoir/infusion pump; without laminectomy
62351     with laminectomy
62360 Implantation or replacement of device for intrathecal or epidural drug infusion; subcutaneous reservoir
62361     nonprogrammable pump
62362     programmable pump, including preparation of pump, with or without programming
64413 Injection, anesthetic agent; cervical plexus [Interscalene nerve block] and [Supraclavicular nerve block for post-operative pain control]
64415     brachial plexus, single [Interscalene nerve block] and [Supraclavicular nerve block for post-operative pain control][Interscalene nerve block] [Supraclavicular nerve block for post-operative pain control] [Not covered for Anterior scalene/brachial plexus block for management of chronic pain]
64416     brachial plexus, continuous infusion by catheter (including catheter placement [Interscalene nerve block] and [Supraclavicular nerve block for post-operative pain control][Interscalene nerve block] [Supraclavicular nerve block for post-operative pain control] [Not covered for Anterior scalene/brachial plexus block for management of chronic pain]
64417 Injection(s), anesthetic agent(s) and/or steroid; axillary nerve [Axillary brachial plexus nerve block]
64420 Injection, anesthetic agent; intercostal nerve, single [subpectoral nerve block (parasternal T2 to T6 intercostal block)][Pecto-intercostal fascial block]
64421      intercostal nerves, multiple, regional block [subpectoral nerve block (parasternal T2 to T6 intercostal block)][Pecto-intercostal fascial block]
64425 Injection(s), anesthetic agent(s) and/or steroid; ilioinguinal, iliohypogastric nerves
64445     sciatic nerve, single
64446     sciatic nerve, continuous infusion by catheter (including catheter placement) [not covered for gluteal nerve injection]
64447     femoral nerve, single arterial line placement [Fascia iliaca block for post-operative pain following hip and knee surgeries] [Not covered for lateral pericapsular nerve group (PENG) nerve block during total hip arthroplasty][Not covered for lateral femoral cutaneous nerve block for the treatment of post-operative pain after total hip arthroplasty]
64448     femoral nerve, continuous infusion by catheter (including catheter placement) [Fascia iliaca block for post-operative pain following hip and knee surgeries] [Not covered for lateral pericapsular nerve group (PENG) nerve block during total hip arthroplasty][Not covered for lateral femoral cutaneous nerve block for the treatment of post-operative pain after total hip arthroplasty]
64450     other peripheral nerve or branch [femoral nerve block for post-operative knee pain] and [quadratus lumborum nerve block for post-operative pain control after abdominal surgery] [lateral femoral cutaneous nerve block for meralgia paresthetica] [Pectoralis nerve block for the management of post-operative pain following mastectomy] [Not covered for multifidus lumborum injection for the treatment of low back pain] [Not covered for radial nerve block for post-operative pain management] [Not covered for superficial cervical plexus block for post-operative pain control after left trans-mastoid endolymphatic shunt][Not covered for deep peroneal nerve for treatment of peroneal neuritis]
64486 Transversus abdominis plane (TAP) block (abdominal plane block, rectus sheath block) unilateral; by injection(s) (includes imaging guidance, when performed) [post-operative pain following abdominal surgery]
64487     by continuous infusion(s) (includes imaging guidance, when performed) [post-operative pain following abdominal surgery]
64488 Transversus abdominis plane (TAP) block (abdominal plane block, rectus sheath block) bilateral; by injections (includes imaging guidance, when performed) [post-operative pain following abdominal surgery]
64489     by continuous infusions (includes imaging guidance, when performed) [post-operative pain following abdominal surgery]
64721 Neuroplasty and/or transposition; median nerve at carpal tunnel
92928 Percutaneous transcatheter placement of intracoronary stent(s), with coronary angioplasty when performed; single major coronary artery or branch
+92929     each additional branch of a major coronary artery (List separately in addition to code for primary procedure)
92933 Percutaneous transluminal coronary atherectomy, with intracoronary stent, with coronary angioplasty when performed; single major coronary artery or branch
+92934     each additional branch of a major coronary artery (List separately in addition to code for primary procedure)
92937 Percutaneous transluminal revascularization of or through coronary artery bypass graft (internal mammary, free arterial, venous), any combination of intracoronary stent, atherectomy and angioplasty, including distal protection when performed; single vessel
+92938     each additional branch subtended by the bypass graft (List separately in addition to code for primary procedure)
92941 Percutaneous transluminal revascularization of acute total/subtotal occlusion during acute myocardial infarction, coronary artery or coronary artery bypass graft, any combination of intracoronary stent, atherectomy and angioplasty, including aspiration thrombectomy when performed, single vessel
92943 Percutaneous transluminal revascularization of chronic total occlusion, coronary artery, coronary artery branch, or coronary artery bypass graft, any combination of intracoronary stent, atherectomy and angioplasty; single vessel
+92944     each additional coronary artery, coronary artery branch, or bypass graft (List separately in addition to code for primary procedure)
92974 Transcatheter placement of radiation delivery device for subsequent coronary intravascular brachytherapy (List separately in addition to code for primary procedure)
95990 Refilling and maintenance of implantable pump or reservoir for drug delivery, spinal (intrathecal, epidural) or brain (intraventricular), includes electronic analysis of pump, when performed

CPT codes for procedures where 76942 and 76998 are not covered for indications listed in the CPB:

Erector spinae plane (ESP) block, Gluteal nerve injection, Hydro dissection of infrapatellar saphenous nerve, Iliotibial band hydro dissection, Lavage of the shoulder joint, Median nerve block, Trigger finger injection/trigger finger release without hydro dissection, clavi-pectoral fascial plane block, iliotibial (IT) band injection, percutaneous bursectomy of the pretibial tubercle bursa, scar tissue injection, hydrodissection of the dorsal scapular nerve and middle/inferior trapezius, rhomboids for peripheral nerve entrapment/ shoulder pain and hydrodissection of scar tissue at the trapezius tendon region, rectus abdominus muscle infiltration for palliative treatment of abdominal wall pain, Plunging ranula in submandibular region, Hydrodissection of Hoffa's fat pad (infra-patellar fat pad), paratenon of patellar tendon, and psoas tendon, Aspiration of plunging ranula in submandibular region, Diagnostic inguinal lymphangiography, Hydrodissection of Hoffa's fat pad (infra-patellar fat pad), paratenon of patellar tendon, and psoas tendon, Iliotibial band bursa injection, Inter-metatarsal bursa injection, Pes anserine bursa injection, Tendon scraping/neovessel ablation for Achilles tendinosis – no specific code
0394T High dose rate electronic brachytherapy, skin surface application, per fraction, includes basic dosimetry, when performed [superficial radiation treatment of skin cancer]
10160 Puncture aspiration of abscess, hematoma, bulla, or cyst [Cyst(s) located in the inferolateral coccyx/sacral region][Post-femoropopliteal bypass graft site] [Hematoma of the gastrocnemius] [Inguinal subcutaneous fluid] [Subcutaneous seroma] [Shoulder or Thigh hematoma] [Subfascial cyst anterior to the proximal talofibular joint] [Identification and aspiration of hematomas following great saphenous veins vein surgery]
20550 Injection(s); single tendon sheath, or ligament, aponeurosis (eg, plantar "fascia") [iliopsoas tendon sheath] [medial calcaneal nerve sheath injection] [Adductor longus tendon injection] [Dorsal compartments of the wrist injection] [gluteal tendon sheath injections for hip and/or low back pain] [iliopsoas tendon injection] [nuchal ligament and supraspinous ligament injection] [peritendon injection for the treatment of Achilles tendinopathy] [peroneal tendon sheath injection][covered for steroid injection into the gluteus maximus tendon] [Adductor brevis and pectineus tendon injection][Covered for piriformis ligament] [Covered for tendon sheath injection of pectoralis minor] [Abductor digiti minimi] [Cervical aponeurosis] [Flexor tendon] [Gluteus medius tendinopathy] [Hamstring tendon] [Lateral epicondylitis] [Latissimus dorsi and lumbar erector fascia] [Knot of Henry] [Myositis ossificans] [Os trigonum syndrome] [Quadriceps tendon] [Retinaculum of knee] [Scapholunate ligament] [Upper trapezius]
20551 Injection(s); single tendon origin/insertion [psoas tendon injection] [Adductor longus tendon injection] [Dorsal compartments of the wrist injection] gluteal tendon sheath injections for hip and/or low back pain] [iliopsoas tendon injection] [nuchal ligament and supraspinous ligament injection] [peritendon injection for the treatment of Achilles tendinopathy] [peroneal tendon sheath injection][covered for steroid injection into the gluteus maximus tendon] [Adductor brevis and pectineus tendon injection]
20552     single or multiple trigger point(s), 1 or 2 muscle(s)
20553     single or multiple trigger point(s), 3 or more muscles
20604 Arthrocentesis, aspiration and/or injection, small joint or bursa (eg, fingers, toes); with ultrasound guidance, with permanent recording and reporting [metatarsophalangeal and/or metatarsal cuneiform joint injection]
20612 Aspiration and/or injection of ganglion cyst(s) any location
26055 Tendon sheath incision (eg, for trigger finger) [Trigger finger injection/trigger finger release without hydro dissection]
24357 – 24359 Tenotomy, elbow, lateral or medial
27000 Tenotomy, adductor of hip, percutaneous
36465 Injection of non-compounded foam sclerosant with ultrasound compression maneuvers to guide dispersion of the injectate, inclusive of all imaging guidance and monitoring; single incompetent extremity truncal vein (eg, great saphenous vein, accessory saphenous vein)
36466     multiple incompetent truncal veins (eg, great saphenous vein, accessory saphenous vein), same leg
36470 Injection of sclerosant; single incompetent vein (other than telangiectasia)
36471     multiple incompetent veins (other than telangiectasia), same leg
38790 Injection procedure; lymphangiography
64405 Injection(s), anesthetic agent(s) and/or steroid; greater occipital nerve
64418 Injection(s), anesthetic agent(s) and/or steroid; suprascapular nerve [dorsal scapular nerve block]
64430 Injection(s), anesthetic agent(s) and/or steroid; pudendal nerve [Treatment of vulvodynia] [Covered for post-operative pain control after hypospadias surgery]
64449     lumbar plexus, posterior approach, continuous infusion by catheter (including catheter placement)
64461 Paravertebral block (PVB) (paraspinous block), thoracic; single injection site (includes imaging guidance, when performed)[Rib plate removal] [Post-operative pain management]
64462 Paravertebral block (PVB) (paraspinous block), thoracic; second and any additional injection site(s) (includes imaging guidance, when performed) (List separately in addition to code for primary procedure)[Rib plate removal] [Post-operative pain management]
64463 Paravertebral block (PVB) (paraspinous block), thoracic; continuous infusion by catheter (includes imaging guidance, when performed)[Rib plate removal] [Post-operative pain management]
64479 Injection(s), anesthetic agent and/or steroid, transforaminal epidural, with imaging guidance (fluoroscopy or CT); cervical or thoracic, single level
+64480     cervical or thoracic, each additional level (List separately in addition to code for primary procedure)
64483     lumbar or sacral, single level
+64484      lumbar or sacral, each additional level (List separately in addition to code for primary procedure)
64493 Injection(s), diagnostic or therapeutic agent, paravertebral facet (zygapophyseal) joint (or nerves innervating that joint) with image guidance (fluoroscopy or CT), lumbar or sacral; single level [Paravertebral nerve block after hip arthroplasty] [Post-operative pain management]
64494      second level (List separately in addition to code for primary procedure) [Paravertebral nerve block after hip arthroplasty] [Post-operative pain management]
64495      third and any additional level(s) (List separately in addition to code for primary procedure) [Paravertebral nerve block after hip arthroplasty] [Post-operative pain management]
64615 Chemodenervation of muscle(s); muscle(s) innervated by facial, trigeminal, cervical spinal and accessory nerves, bilateral (eg, for chronic migraine)
64616 Chemodenervation of muscle(s); neck muscle(s), excluding muscles of the larynx, unilateral (eg, for cervical dystonia, spasmodic torticollis)
77767 Remote afterloading high dose rate radionuclide skin surface brachytherapy, includes basic dosimetry, when performed; lesion diameter up to 2.0 cm or 1 channel [superficial radiation treatment of skin cancer]
77768 Remote afterloading high dose rate radionuclide skin surface brachytherapy, includes basic dosimetry, when performed; lesion diameter over 2.0 cm and 2 or more channels, or multiple lesions [superficial radiation treatment of skin cancer]

HCPCS codes for procedures where 76942 and 76998 are not covered for indications listed in the CPB:

J7318 Hyaluronan or derivative, durolane, for intra-articular injection, 1 mg
J7320 Hyaluronan or derivitive, genvisc 850, for intra-articular injection, 1 mg
J7321 Hyaluronan or derivative, Hyalgan, Supartz or Visco-3, for intra-articular injection, per dose
J7322 Hyaluronan or derivative, hymovis, for intra-articular injection, 1 mg
J7323 Hyaluronan or derivative, Euflexxa, for intra-articular injection, per dose
J7324 Hyaluronan or derivative, Orthovisc, for intra-articular injection, per dose
J7325 Hyaluronan or derivative, Synvisc, or Synvisc-One for intra-articular injection, 1 mg
J7326 Hyaluronan or derivative, Gel-One, for intra-articular injection, per dose
J7327 Hyaluronan or derivative, Monovisc, for intra-articular injection, per dose
J7328 Hyaluronan or derivative, for intra-articular injection, 0.1 mg [Gel-Syn]

Ultrasound guidance for vascular access:

CPT codes covered if selection criteria are met:

+76937 Ultrasound guidance for vascular access requiring ultrasound evaluation of potential access sites, documentation of selected vessel patency, concurrent realtime ultrasound visualization of vascular needle entry, with permanent recording and reporting (List separately in addition to code for primary procedure)
76998 Ultrasonic guidance, intraoperative

CPT codes for procedures where 76937 and 76998 are covered if selection criteria are met (not all inclusive):

36555 Insertion of non-tunneled centrally inserted central venous catheter; younger than 5 years of age
36556     age 5 years or older
36557 Insertion of tunneled centrally inserted central venous catheter, without subcutaneous port or pump; younger than 5 years of age
36558     age 5 years or older
36560 Insertion of tunneled centrally inserted central venous access device, with subcutaneous port; younger than 5 years of age
36561     age 5 years or older
36563 Insertion of tunneled centrally inserted central venous access device with subcutaneous pump
36565 Insertion of tunneled centrally inserted central venous access device, requiring 2 catheters via 2 separate venous access sites; without subcutaneous port or pump (eg, Tesio type catheter)
36566     with subcutaneous port(s)
36570 Insertion of peripherally inserted central venous access device, with subcutaneous port; younger than 5 years of age
36571     age 5 years or older
36575 Repair of tunneled or non-tunneled central venous access catheter, without subcutaneous port or pump, central or peripheral insertion site
36576 Repair of central venous access device, with subcutaneous port or pump, central or peripheral insertion site
36578 Replacement, catheter only, of central venous access device, with subcutaneous port or pump, central or peripheral insertion site
36580 Replacement, complete, of a non-tunneled centrally inserted central venous catheter, without subcutaneous port or pump, through same venous access
36581 Replacement, complete, of a tunneled centrally inserted central venous catheter, without subcutaneous port or pump, through same venous access
36582 Replacement, complete, of a tunneled centrally inserted central venous access device, with subcutaneous port, through same venous access
36583 Replacement, complete, of a tunneled centrally inserted central venous access device, with subcutaneous pump, through same venous access
36585 Replacement, complete, of a peripherally inserted central venous access device, with subcutaneous port, through same venous access
36589 Removal of tunneled central venous catheter, without subcutaneous port or pump
36590 Removal of tunneled central venous access device, with subcutaneous port or pump, central or peripheral insertion
50040 - 50081 Incision, renal
50220 - 50240 Excision, renal
50384 - 50386 Introduction, renal
50390 - 50431, 50433, 50435 Other Introduction, renal
50541, 50543 - 50549 Laparoscopy, renal
50590 - 50593 Lithotripsy

Background

In the past 10 years, ultrasound (US) has become increasingly popular to image both peripheral musculoskeletal and axial structures.  Presently, US is often used to guide interventions such as aspiration, hydrodissection, tenotomy, as well as diagnostic or therapeutic injections (e.g., epidural, facet joint, intra-articular, sacroiliac joint, subtalar joint, trigger point and viscosupplement injections).  This clinical policy bulletin describes some of the medically necessary as well as experimental/investigational indications associated with the use of US guidance.

Ultrasound Guidance: Medically Necessary Indications

Adductor Canal Nerve Block 

An UpToDate review on "Lower extremity nerve blocks: Techniques" (Jeng and Rosenblatt, 2019a) states that "The saphenous nerve is the terminal sensory branch of the femoral nerve.  The saphenous nerve block is useful for ambulatory surgeries of the superficial, medial lower leg and provides analgesia of the medial ankle and foot.  It can be blocked at the level of the tibial tuberosity below the knee, above the knee using the adductor canal block, or at the ankle as part of an ankle block.  Adductor canal block – The saphenous nerve is blocked at the level of the mid-thigh with the adductor canal block using ultrasound guidance … Ultrasound-guided adductor canal block – The ultrasound probe is placed perpendicular to the thigh at the midpoint between the anterior superior iliac spine and the base of the patella.  The nerve is identified as it lies adjacent to the femoral artery.  It is followed distally as it becomes more superficial, traveling with an arterial branch just deep to the sartorius muscle.  Using an in-plane approach, after negative aspiration, 10 ml of local anesthetic (LA) is injected deep to the sartorius muscle, at the lateral border of the artery".

Manickam et al (2009) noted that saphenous nerve (SN) block can be technically challenging because it is a small and exclusively sensory nerve.  Traditional techniques using surface landmarks and nerve stimulations are limited by inconsistent success rates.  In a prospective study, these researchers examined the feasibility of performing an ultrasound (US)-guided SN block in the distal thigh.  After the research ethics board's approval and written informed consent, a total of 20 patients undergoing ankle or foot surgery underwent ultrasonography of the medial aspect of the thigh to identify the SN in the adductor canal, as it lies adjacent to the femoral artery (FA), deep to the sartorius muscle.  An insulated needle was advanced in plane under real-time guidance toward the nerve.  After attempting to elicit paresthesia with nerve stimulation, 2 % lidocaine with 1:200,000 epinephrine (5 ml) and 0.5 % bupivacaine (5 ml) were injected around the SN.  The SN was identified in all patients, most frequently in an antero-medial position relative to the FA, at a depth of 2.7 +/- 0.6 cm and 12.7 +/- 2.2 cm proximal to the knee joint.  Complete anesthesia in the SN distribution developed in all patients by 25 mins after injection.  The authors concluded that in this small, descriptive study, US-guided SN block in the adductor canal was technically simple and reliable, providing consistent nerve identification and block success.

Messeha (2016) stated that lumbar plexus block, combined with a sciatic nerve block, is an effective loco-regional anesthetic technique for analgesia and anesthesia of the lower extremity.  These researchers compared the clinical results outcome of the adductor canal block versus the psoas compartment block combined with sciatic nerve block using real time US guidance in patients undergoing elective laparoscopic knee surgeries.  A total of 90 patients who were undergoing elective laparoscopic knee surgeries were randomly allocated to receive a sciatic nerve block in addition to lumbar plexus block using either an adductor canal block (ACB) or a posterior psoas compartment approach (PCB) using 25-ml of bupivacaine 0.5 % with adrenaline 1:400,000 injection over 2 to 3 mins while observing the distribution of the local anesthetic in real time.  Successful nerve block was defined as a complete loss of pinprick sensation in the region that is supplied by the 3 nerves along with adequate motor block, 30 mins after injection.  The degree of motor block was evaluated 30 mins after the block procedure.  The results of the present study showed that the real time US guidance of PCB is more effective than ACB approach.  Although the sensory blockade of the femoral nerve achieved equally by both techniques, the LFC and OBT nerves were faster and more effectively blocked with PCB technique.  Furthermore, PCB group showed significant complete sensory block without need for general anesthesia, significant decrease in the post-operative visual analog scale (VAS) and significant increase time of 1st analgesic requirement as compared to the ACB group.  The authors concluded that the findings of this study showed that blockade of lumber plexus by psoas compartment block was more effective in complete sensory block without general anesthesia supplementation in addition to decrease post-operative analgesic requirement than adductor canal block.  The subjects in this study underwent laparoscopic knee surgeries, not ankle surgeries.

The authors stated that this study had several drawbacks.  The exclusion of obese patients led to that the incidence of success in patients with body mass index (BMI) of greater than 35 kg/m2 could not be determined, as US visibility of the lumbar paravertebral structures in obese patients was poorer than that observed in patients with low BMI.  Another limitation was the wide range of age group and changes in musculoskeletal structures, especially in the elderly patients (greater than 65 years of age) that could reduce the contrast between a peripheral nerve and its surrounding muscles and could adversely affect the quality of US images.  Furthermore, patients with abnormal spinal anatomy, due to either spinal deformity or history of previous back or spine surgery also demonstrated poor image quality.

Aspiration of Breast Seroma

An UpToDate review on “Complications of reconstructive and aesthetic breast surgery” (Nahabedian, 2023) states that “Seromas that occur early can be drained percutaneously (with or without ultrasound guidance), with or without placement of a short-term drainage catheter.  Care must be taken to avoid damaging an implant.  If an infection is suspected, the drained fluid can be sent for culture.  If a drain is placed, it is typically left in place for 1 to 2 weeks until drainage is ≤ 30 mL over a 24-hour period”. 

Axillary Brachial Plexus Nerve Block

Klaastad and co-workers (2009) noted that many of the reports concluded that US guidance may provide a higher success rate for brachial plexus blocks than guidance by nerve stimulator.  However, the studies were not large enough to conclude that US will reduce the risk of nerve injury, local anesthetic toxicity or pneumothorax.  Ultrasound may reveal anatomical variations of importance for performing brachial plexus blocks.  For post-operative analgesia, 5 ml of ropivacaine 0.5 % has been sufficient for an US-guided interscalene block.  For peri-operative anesthesia, as much as 42 ml of a local anesthetic mixture was calculated to be appropriate for an US-guided supraclavicular method.  For the future, these investigators noticed that 3D- and 4D-US technology may facilitate visualizing the needle, the nerves and the local anesthetic distribution.  Impedance measurements may be helpful for nerve blocks not guided by US.  The authors concluded that the literature gave a sufficient basis to recommend the use of US for guidance of brachial plexus blocks.

Nadeau and associates (2013) reviewed the main US-guided approaches used for regional anesthesia of the upper limb.  The anatomical configuration of the upper limb, with nerves often bundled around an artery, makes regional anesthesia of the arm both accessible and reliable.  In-depth knowledge of upper limb anatomy is needed to match the blocked territory with the surgical area.  The interscalene block is the approach most commonly used for shoulder surgery.  Supra-clavicular, infra-clavicular, and axillary blocks are indicated for elbow and forearm surgery.  Puncture techniques have evolved dramatically with US guidance.  Instead of targeting the nerves directly, it is now recommended to look for diffusion areas.  Typically, local anesthetics are deposited around vessels, often as a single injection.  Phrenic nerve block can occur with the interscalene and supra-clavicular approaches.  Ulnar nerve blockade is almost never achieved with the interscalene approach and not always present with a supra-clavicular block.  If US guidance is used, the risk for pneumothorax with a supra-clavicular approach is reduced significantly.  Nerve damage and vascular puncture are possible with all approaches.  If an axillary approach is chosen, the consequences of vascular puncture can be minimized because this site is compressible.  The authors concluded that upper limb regional anesthesia has gained in popularity because of its safety profile and effectiveness associated with US-guided techniques.

Xu and colleagues (2017) examined the safety and efficacy of bilateral axillary brachial plexus block under US-guidance or neurostimulator-guidance.  From February 2012 to April 2014, a total of 120 patients undergoing bilateral hand/forearm surgery were anesthetized with bilateral axillary brachial plexus block.  All patients were divided into 2 groups randomly using random number table: the US-guided group (group U, n = 60) and the neurostimulator-guided group (group N, n = 60).  The block was performed with 0.5 % ropivacaine.  Patients' age, sex and operation duration were recorded.  Moreover, success rate, performance time, onset of sensor and motor block, performance pain, patient satisfaction degree and the incidence of related complications were also documented.  Venous samples were collected at selected time-points and the total and the plasma concentrations of ropivacaine were analyzed with HPLC.  The performance time, the onset of sensor block and the onset of motor block of group U were (8.2 ± 1.5), (14.2 ± 2.2)and (24.0 ± 3.5) mins, respectively, which were markedly shorter than those in group N ( (14.6 ± 3.9), (19.9 ± 3.8), (28.8 ± 4.2) mins, respectively), and the differences were statistically significant (t = 11.74, 10.09, 6.73, respectively, all p < 0.01).  The performance pain score of group N was (25.5 ± 13.2), which was obviously more serious than group U (31.7 ± 11.2) and a significant statistical difference was detected (t = 2.856, p < 0.05).  The patient satisfaction degree of group U was 95.0 %, which was significantly higher than group N (83.3 %) and a markedly statistical difference was detected (χ(2) = 4.227, p < 0.05); 50 mins after performance, the total plasma concentration of ropivacaine of group U was (1.76 ± 0.48 mg/L), which was significantly lower than group N (1.88 ± 0.53 mg/L) and a significant statistical difference was detected (t = 2.43, p < 0.05), while no significant differences were detected at the other time-points between 2 groups (p > 0.05).  No analgesic was super-added and no other anesthesia methods were applied.  No complications were detected peri-operatively.  The authors concluded that the bilateral axillary brachial plexus block under US-guidance or neurostimulator-guidance were both safe and effective for bilateral hand/forearm surgery.  However, the US-guided block may be more clinically beneficial because of its shorter performance time, rapid onset and higher patient satisfaction degree.

Li and associates (2020) stated that neurostimulator-guidance and US-guidance are 2 major methods that have been widely accepted and applied in axillary brachial plexus block.  However, the differences between the effects of these 2 types of guidance still need to be further elucidated for clinical usage.  This study included a total of 208 patients undergoing elective upper limb surgeries and receiving axillary brachial plexus block.  The patients were randomly assigned to receive either US-guidance (group U, n = 112) or nerve stimulation (group N, n = 96).  Pinprick test was performed for assessing the sensory blockades.  The pain was evaluated by visual analog scale (VAS).  Reactive oxygen species (ROS) levels were measured by dichloro-dihydro-fluorescein diacetate staining and serum levels of nitric oxide (NO), nitric oxide synthases (NOS), tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein 1 (MCP1) were evaluated by ELISA.  Results showed that US-guidance significantly enhanced the quality of the sensory blockade and reduced the VAS scores when compared with the neurostimulator-guidance.  In addition, the production of ROS, NO, NOS, TNF-α, and MCP-1 were significantly alleviated by US-guidance.  The authors concluded that US-guided brachial plexus block relieved pain during operation, provided higher success rates in the nerve block, caused less vascular damage and resulted in lower levels of inflammatory cytokines secretion when compared with neurostimulator-directed brachial plexus blockage.

C5-C7 Interscalene Nerve Block

In a prospective, randomized, triple-blinded study, Fredrickson and Price (2009) tested the hypothesis that a 48-hour continuous C5-C6 root/superior trunk patient-controlled infusion of ropivacaine 0.4 % would provide superior analgesia after shoulder surgery compared with the same infusion of ropivacaine 0.2 %.  Patients presenting for painful shoulder surgery were recruited.  A perineural catheter was placed under ultrasound (US) guidance immediately adjacent to the C5-C6 roots/superior trunk.  Ropivacaine 5 mg ml(-1) (30 ml) was administered via this catheter before surgery under general anesthesia.  At the end of surgery, patients were randomized to receive ropivacaine 2 mg ml(-1) (0.2 %) (n = 32) or 4 mg ml(-1) (0.4 %) (n = 33) via an elastomeric pump delivering 2 ml h(-1) with on-demand patient-controlled boluses of 5 ml as needed.  Acetaminophen and diclofenac were administered if any post-operative pain occurred, ropivacaine boluses for a numerical rating pain score (NRPS, 0 to 10) of greater than 2, and rescue tramadol for an NRPS greater than 3.  All patients were phoned on post-operative days 1 and 2 and questioned for indices of treatment effectiveness and adverse effects.  NRPS, patient ropivacaine demands, and supplemental tramadol consumption were similar in each group [median “average daily pain” days 1/2 (0.2 % = 1/3, 0.4 % = 2/3)].  Episodes of an insensate/densely blocked arm occurred only with ropivacaine 0.4 % (5 versus 0 episodes, p = 0.05).  Satisfaction (numerical rating scale, 0 to 10) was higher for ropivacaine 0.2% (mean difference [MD] 1.3; 95 % confidence interval [CI]: 0.3 to 2.4; p = 0.01).  The authors concluded that after major shoulder surgery, ropivacaine 0.2 % at 2 ml h(-1) with on-demand 5 ml boluses administered via an US-guided C5-6 root/superior trunk peri-neural catheter produced similar analgesia, but higher patient satisfaction compared with ropivacaine 0.4 %.

Shin et al (2011) stated that continuous interscalene block has been known to improve post-operative analgesia after arthroscopic shoulder surgery.  In a prospective study, these investigators examined the US-guided posterior approach for placement of an interscalene catheter, clinical efficacy and complications after placement of the catheter.  A total of 42 patients undergoing elective arthroscopic shoulder surgery were included in this study and an interscalene catheter was inserted under the guidance of US with posterior approach.  With the in-plane approach, the 17-G Tuohy needle was advanced until the tip was placed between the C5 and C6 nerve roots.  After a bolus injection of 20-ml of 0.2 % ropivacaine, a catheter was threaded and secured.  A continuous infusion of ropivacaine 0.2 % 4 ml/hour with patient-controlled 5-ml boluses every hour was used over 2 days.  Difficulties in placement of the catheter, clinical efficacy of analgesia and complications were recorded.  All patients were monitored for 48 hours and examined by the surgeon for complications within 2 weeks of hospital discharge.  Easy placement of the catheter was achieved in 100 % of the patients and the success rate of catheter placement during the 48-hour period was 92.9 %.  Post-operative analgesia was effective in 88.1 % of the patients in the post anesthetic care unit (PACU).  The major complications included nausea (7.1 %), vomiting (4.8 %), dyspnea (4.8 %) and unintended vascular punctures (2.4 %).  Other complications such as neurologic deficits and local infection around the puncture site did not occur.  The authors concluded that US-guided interscalene block with a posterior approach was associated with a success high rate in placement of the interscalene catheter and a low rate of complications; however, the small sample size limited these researchers to draw definite conclusions; thus, a well-designed randomized controlled trial (RCT) is needed to confirm these preliminary findings.

Finlayson et al (2014) stated that US guidance offers an alternative to fluoroscopy for medial branch blocks of the upper cervical spine; however, it may be less accurate for blocks at the C5 and C6 levels.  These researchers hypothesized that a modified technique using biplanar US imaging would facilitate level identification and provide greater accuracy for the lower cervical spine.  A total of 40 patients with chronic neck pain underwent US-guided blocks of the C5 and C6 medial branches.  For each level, 0.3-ml of a local anesthetic/iodinated contrast mixture was injected.  Postero-lateral in-plane needle placement was performed in a transverse view, and the position of the needle tip was verified in the coronal plane using the C7 transverse process as a sonographic landmark.  Contrast distribution, as assessed by a blinded observer on antero-posterior and lateral x-ray views, constituted the primary outcome.  Secondary outcomes were performance time and pain relief 30 mins after the blocks; 100 % and 97.5 % of C5 and C6 levels, respectively, demonstrated appropriate contrast distribution.  The C7 transverse process was readily identified in the coronal plane in all but 2 subjects.  Performance time was 248.8 ± 82.7 seconds; the mean percentage of relief provided by the blocks was 76.9 % ± 25.5 %.  In 30 % of patients, a blood vessel was visualized crossing the C6 articular pillar and successfully avoided during needle insertion.  The authors concluded that US guidance using a biplanar approach was a reliable imaging modality for C5 and C6 medial branch blocks.

Falyar et al (2016) noted that US-guided selective C5 nerve root blocks have been described in several case reports as a safe and effective means to anesthetize the distal clavicle while maintaining innervation of the upper extremity and preserving diaphragmatic function.  In this study, cadavers were injected with 5-m of 0.5 % methylene blue dye under US guidance to examine possible proximal and distal spread of injectate along the brachial plexus, if any.  Following the injections, the specimens were dissected and examined to determine the distribution of dye and the structures affected.  One injection revealed dye extended proximally into the epidural space, which penetrated the dura mater and was present on the spinal cord and brainstem.  Dye was noted distally to the divisions in 3 injections.  The anterior scalene muscle and phrenic nerve were stained in all 4 injections.  It appeared unlikely that local anesthetic spread was limited to the nerve root following an US-guided selective C5 nerve root injection.  Under certain conditions, intrathecal spread also appeared possible, which has major patient safety implications.  Additional safety measures, such as injection pressure monitoring, should be incorporated into this block, or approaches that are more distal should be considered for the acute pain management of distal clavicle fractures.

Furthermore, an UpToDate review on “Interscalene block procedure guide” (Wilson and Klesius, 2021) provides the following information:

  • The interscalene block (ISB) targets the interscalene groove between the anterior and middle scalene muscles at the level of the sixth cervical vertebra;
  • The ISB usually anesthetizes the C5 to C7 nerve roots, as well as the supraclavicular branches of the cervical plexus (C1 to C3), and usually spreads to block C7;
  • The ISB is a reliable block for shoulder surgery and distal clavicle surgery.

Ultrasound versus nerve stimulation guidance: We use ultrasound guidance for ISB, and occasionally use nerve stimulation to confirm the needle tip location if the ultrasound image is unclear or difficult to obtain. Ultrasound guidance improves the quality of ISB for surgical anesthesia compared with nerve stimulation guidance, but similar quality and duration of postoperative analgesia.

Carpal Tunnel Release

Leiby et al (2021) examined the long-term safety and effectiveness of carpal tunnel release (CTR) using US guidance (CTR-US) in a group of patients treated by a single physician.  The study group consisted of 76 consecutive CTRs performed on 47 patients between June 2017 and April 2019 for whom 1-year follow-up was available.  All procedures were performed by the same operator using a single CTR technique.  Outcomes included complications; Boston Carpal Tunnel Questionnaire symptom severity score (BCTQ-SSS) and functional status score (BCTQ-FSS); Quick Disabilities of the Arm, Shoulder, and Hand (QDASH) scores; and a 5-point global satisfaction score (4 = satisfied, 5 = very satisfied).  The 47 patients included 27 women and 20 men (ages of 31 to 91 years); 25 patients (50 hands) had simultaneous bilateral CTRs, 4 patients (8 hands) had staged bilateral CTRs, and 18 patients had unilateral CTRs.  No complications occurred.  Statistically and clinically significant reductions in BCTQ-SSS, BCTQ-FSS, and QDASH scores occurred by 1 to 2 weeks post-CTR and persisted at 1-year (mean 1-year changes versus pre-CTR -2.11, -1.70, and -44.99, respectively; p < 0.001 for all).  The mean global satisfaction score at 1-year was 4.63.  The authors concluded that CTR-US was a safe and effective procedure that produced statistically and clinically significant improvements within 1 to 2 weeks post-procedure that persisted to 1 year.  Furthermore, simultaneous bilateral CTR-US are feasible and may be advantageous for patients who are candidates for bilateral CTR.

Kamel et al (2021) stated that CTR-US allows performance of CTR with smaller incisions and quicker recovery than traditional open or endoscopic surgery.  These investigators examined the long-term effectiveness of CTR-US in improving function and discomfort in patients with CTS.  They carried out retrospective review of 61 CTR-US procedures performed on 46 patients (15 bilateral procedures) with clinically diagnosed CTS.  The procedures were performed with a single-use transection device and local anesthesia at an outpatient radiology office.  Patients answered 3 questionnaires (QDASH and 2 parts of the BCTSQ-SSS and BCTSQ-FSS) to assess the function of and discomfort in the affected wrist immediately before and 2 weeks and at least 1 year after the procedure.  Higher scores indicated increasing disability.  Patients also answered a global satisfaction question at follow-up.  Pre-procedure and post-procedure scores were compared by paired Wilcoxon signed rank tests.  The 46 patients (25 women, 21 men; mean age of 60.6 years; range of 21 to 80 years) had median pre-procedure scores of 45.4 for QDASH, 3.2 for BCTSQ-SSS, and 2.5 for BCTSQ-FSS.  The median scores 2 weeks after the procedure were 22.5 for QDASH, 1.7 for BCTSQ-SSS, and 1.9 for BCTSQ-FSS.  All scores decreased (p < 0.001) from pre-procedure scores and surpassed reference standards for clinically important difference in scores.  Follow-up questionnaires obtained for 90 % (55/61) of wrists a median of 1.7 years (range of 1.0 to 2.8 years) after the procedure showed further declines (p < 0.001) in median scores: 2.3 for QDASH, 1.2 for BCTSQ-SSS, and 1.1 for BCTSQ-FSS.  At long-term follow-up evaluation, 96 % (52/54) of wrists had lower QDASH and 98 % (53/54) had lower BCTSQ (average of BCTSQ-SSS and BCTSQ-FSS) scores compared with the pre-procedure scores.  Among the patients who participated in the survey, 93 % (37/40) were satisfied or very satisfied with the long-term outcomes.  No immediately post-operative complications occurred.  Two patients needed surgical intervention 8 and 10 days after surgery, 1 for infection after injury and 1 for post-traumatic compartment syndrome.  The authors concluded that CTR-US improved hand function and reduced hand discomfort; improvement persisted beyond 1 year.

Loizides et al (2021) presented a safety-optimized CTR-US procedure.  A total of 104 patients (67 women, 37 men; mean age of 60.6 ± 14.3 years, 95 % CI: 57.9 to 63.4 years) with clinical and electrophysiological verified typical CTS were referred for a high-resolution US of the median nerve and were then consecutively assigned for an US-guided CTR after exclusion of possible secondary causes of CTS such as tumors, tendo-vaginitis, ganglia and possible contraindications (e.g., crossing collateral vessels, nerve variations).  CTR was performed using a button tip cannula which has several safety advantages: On the one hand, the button tip cannula acted as a blunt and atraumatic guiding splint for the subsequent insertion of the hook-knife, and on the other hands, it served as a "hydro-inflation"-tool, i.e., a fluid-based expansion of the working-space was needed during the whole procedure whenever needed.  In all patients, successful releases were confirmed by the depiction of a completely transected transverse carpal ligament during and in the post-operative US-controls 2 weeks after intervention.  All patients reported markedly reduction of symptoms promptly after this safety-optimized US-guided minimal invasive CTR and at the follow-up examination.  No complications were evident.  The authors concluded that the here proposed optimized algorithm assured a reliable and safe US-guided CTR; and thus, should be taken into account for this minimal invasive interventional procedure.

Van Boxstael et l (2022) noted that local anesthetics are often selected or mixed to accomplish faster onset of anesthesia; however, with US guidance, local anesthetics are delivered with greater precision, which may shorten the onset time with all classes of local anesthetics.  In a randomized clinical trial, these researchers compared onset time and duration of US-guided wrist blocks with a fast onset versus a longer lasting local anesthetic administered via single or dual (spatially separate) injections at the level of the mid-forearm.  A total of 36 subjects scheduled for CTR were randomly assigned to receive US-guided median and ulnar nerve blocks with lidocaine 2 % or bupivacaine 0.5 % via single or dual injections (n = 9 in each group).  Subjects fulfilled the study requirements.  The main outcome variables were onset and duration of sensory blockade, which were tested separately in 2 (drug) × 2 (injection) analysis of variances (ANOVAs) with interaction terms.  Sensory block onset time did not differ significantly between subjects given lidocaine 2 % (9.2 ± 3.4 mins) or bupivacaine 0.5 % (9.5 ± 3.1 mins) (p = 0.76; mean difference [MD], -0.3 ± 1.1 mins [95 % confidence interval {CI}: -2.5 to 1.9]) or between the single- (9.6 ± 2.8 mins) and dual- (9.1 ± 3.6 mins) injection groups (p = 0.69; MD, -0.4 ± 1.1 mins [95 % CI: -1.8 to 2.6]).  Sensory duration was longer for subjects in the bupivacaine 0.5 % group (27.3 ± 11.6 hours) than for subjects in the lidocaine 2 % group (8.4 ± 4.1 hours) (p < 0.001; 95 % CI: 12.7 to 25.1).  However, sensory duration in the single- (15.7 ± 12.5 hours) and dual- (19.4 ± 13.1 hours) injection groups did not differ significantly (p = 0.28; MD, -3.7 ± 4.3 hours [95 % CI: -12.6 to 5.1]).  The authors concluded that no significant effect was found for onset time between lidocaine 2 % and bupivacaine 0.5 % used in US-guided wrist blocks.  Dual injections did not shorten onset time.  Since mean nerve block duration was longer with bupivacaine 0.5 %, these findings suggested that the selection of local anesthetic for the median and ulnar nerves at the level of the mid-forearm should be based on the desired duration of the block and not on its speed of onset.

In a multi-center post-market registry, Fowler et al (2022) reported outcomes of patients who underwent CTR-US in routine clinical practice.  This study included patients who were treated with CTR-US.  Main outcomes included the QDASH, BCTQ-SSS and BCTQ-FSS, return-to-normal activities, return-to-work, and complications.  Of 535 patients who provided follow-up data, 373 (70 %) were followed for 6 months post-treatment.  Among these 373 patients (427 hands, mean age of 55 years, 71 % women), QDASH scores decreased by 30.8 points, BCTQ-SSS scores decreased by 1.6 points, and BCTQ-FSS scores decreased by 1.0 points at 6 months (all p < 0.001).  The median time to return-to-normal activities was 3 days and time to return-to-work was 5 days.  Subgroup analysis revealed consistent outcomes regardless of age group, sex, BMI, diabetes, tobacco use, worker compensation status, or procedure type (unilateral/bilateral simultaneous).  No major neurovascular complications were reported.  The authors concluded that patients treated with CTR-US reported clinically meaningful improvements in symptoms and function, rapid return-to-normal activities, and minimal work absenteeism, with an excellent safety profile.

Furthermore, an UpToDate review on “Surgery for carpal tunnel syndrome” (Hunter and Simmons, 2022) states that “Carpal tunnel release can be performed as an open procedure, endoscopically, or by using ultrasound-guided ultra-minimally invasive techniques.  The long-term outcomes of open, endoscopic, and ultrasound-guided ultra-minimally invasive carpal tunnel release are equivalent.  Ultra-minimally invasive techniques have the advantage of quicker recovery but the potential for a higher rate of recurrence”.

Fascia Iliaca Block for the Management of Post-Operative Pain Following Hip and Knee Surgeries, and Repair of Femur Fracture

In a meta-analysis, Wang et al (2017) compared the safety and efficiency between femoral nerve block (FNB) and fascia iliaca block (FIB) for post-operative pain control in patients undergoing total knee and hip arthroplasties.  These investigators carried out a systematic search in Medline (1966 to 2017.05), PubMed (1966 to 2017.05), Embase (1980 to 2017.05), ScienceDirect (1985 to 2017.05) and the Cochrane Library.  Inclusion criteria:

  1. Participants: Only published articles enrolling adult participants that with a diagnosis of end-stage of osteoarthritis (OA) and prepared for unilateral total knee arthroplasty (TKA) or THA;
  2. Interventions: The intervention group received FIB for post-operative pain management;
  3. Comparisons: The control group received FNB for post-operative pain control;
  4. Outcomes: VAS scores in different periods, opioids consumption, length of stay (LOS) and post-operative complications;
  5. Study design: clinical RCTs were regarded as eligible in this study. 

Cochrane Hand book for Systematic Reviews of Interventions was used for assessment of the included studies and risk of bias was shown.  Fixed/random effect model was used according to the heterogeneity tested by I2 statistic.  Sensitivity analysis was conducted and publication bias was assessed.  Meta-analysis was performed using Stata 11.0 software.  A total of 5 RCTs including 308 patients met the inclusion criteria.  The present meta-analysis indicated that there were no significant differences between groups in terms of VAS score at 12 hours (SMD = -0.080, 95 % CI: -0.306 to 0.145, p = 0.485), 24 hours (SMD = 0.098, 95 % CI: -0.127 to 0.323, p = 0.393), and 48 hours (SMD = -0.001, 95 % CI: -0.227 to 0.225, p = 0.993).  No significant differences were found regarding opioid consumption at 12 hours (SMD = 0.026, 95 % CI: -0.224 to 0.275, p = 0.840), 24 hours (SMD = 0.037, 95 % CI: -0.212 to 0.286, p = 0.771), and 48 hours (SMD = -0.016, 95 % CI: -0.265 to 0.233, p = 0.900).  In addition, no significant increase of complications was identified between groups.  The authors concluded that there was no significant differences of VAS scores at 12 to 48 hour and opioids consumption at 12 to 48 hour between 2 groups following total joint arthroplasty.  No increased risk of nausea, vomiting and pruritus was observed in both groups.  These investigators stated that FNB provided equal post-operative pain control compared with FIB following total joint arthroplasty.  Both of them could reduce the consumption of opioids without severe adverse effects.

Gao et al (2019) stated that optimal pain management after total hip arthroplasty (THA) remains controversial.  These researchers carried out a meta-analysis from randomized controlled trials (RCTs) to examine the safety and efficacy of fascia iliaca compartment block (FICB) in THA.  They conducted electronic searches of PubMed, Medline, Cochrane library, and Web of Science before February 2019.  These researchers collected RCTs to compare FICB and placebo for pain control after THA.  The outcome measurements consisted of pain score, opioid consumption, length of hospitalization and post-operative complications.  All data analyses were conducted using STATA 13.0.  Cochrane Collaboration's tool was adopted to assess the risk of bias.  A total of 7 RCTs met the inclusion criteria with 165 patients in the FICB groups, and 160 patients in the placebo groups.  The present meta-analysis indicated that there were significant differences between the groups in terms of pain score at post-operative 12 hours (weighed mean difference [WMD] = -0.285, 95 % confidence interval [CI]: -0.460 to  -0.109, p = 0.002) and 24 hours (WMD = -0.391, 95 % CI: -0.723 to  -0.059, p = 0.021).  FICB was associated with significant superior in opioid consumption at post-operative 12 hours (WMD = -5.394, 95% CI: -8.772 to  -2.016, p = 0.002) and 24 hours (WMD = -6.376, 95 % CI: -10.737 to -2.016, p = 0.004) compared with placebo.  No significant difference was identified regarding length of hospitalization (WMD = 0.112, 95 % CI: -0.125 to 0.350, p = 0.354).  The authors concluded that fascia iliaca compartment block was effective for pain relief during the early post-operative period after THA.  Meanwhile, it reduced the cumulative morphine consumption and the risk of opioid-related adverse effects.

In a meta-analysis, Cai et al (2019) examined the effect of FICB on pain control and morphine consumption in patients with THA.  These investigators searched databases (PubMed, Embase, Cochrane Library) for eligible randomized controlled trials (RCTs) published prior to September 12, 2018.  They only included THA patients who received FICB versus placebo for pain control.  Risk ratios (RRs), standard MD (SMD) and 95 % CI were determined.  Stata 12.0 was used for the meta-analysis.  A total of 326 THA patients from 7 RCTs were subjected to meta-analysis.  Overall, FICB was associated with lower visual analog scale (VAS) scores at 1 to 8 hours and 12 hours compared with placebo (p < 0.05).  However, there was no significant difference between VAS at 24 hours (SMD = -0.56, 9 5% CI: -1.42 to 0.31, p = 0.206) and 48 hours after THA (SMD = -0.82, 95 % CI: -2.07 to 0.44, p = 0.204).  Compared with the control group, FICB significantly decreased the occurrence of nausea (RR = 0.41, 95 % CI: 0.25 to 0.69, p = 0.010; I2 = 0.0 %).  There was no significant difference in the risk of falls between the FICB and control groups (p > 0.05).  The authors concluded that FICB had a beneficial role in reducing pain intensity and morphine consumption after THA.  Moreover, FICB had morphine-sparing effects when compared with a control group.

Diakomi et al (2020) stated that chronic post-surgical pain (CPSP), i.e., pain persisting greater than 3 months, may appear after any type of surgery.  There is a paucity of literature addressing CPSP development after hip fracture repair and the impact of any analgesic intervention on the development of CPSP in patients after hip fracture surgery.  In a prospective. randomized study, these researchers examined the impact of ultrasound-guided FICB (USG-FICB) on the development of CPSP after hip fracture repair.  A total of 182 patients scheduled for hip fracture surgery were included in this trial.  Patients were randomized to receive a USG-FICB (FICB group) or a sham saline injection (sham FICB group), 20 mins before positioning for spinal anesthesia.  The hip-related characteristic pain intensity (CPI) at 3-months post-surgery was the primary outcome measure.  Presence and severity of hip-related pain at 3- and 6-months post-surgery, NRS scores at 6, 24, 36, 48 post-operative hours, total 24-hour tramadol patient-controlled analgesia (PCA) administration and timing of the first tramadol dose, were documented as well.  FICB group presented with lower CPI scores 3-months post-operatively (p < 0.01), as well as lower percentage of patients with high-grade CPSP, 3 and 6 months post-operatively (p < 0.001).  FICB group also showed significantly lower NRS scores in all instances, lower total 24-hour tramadol consumption and higher mean time to first tramadol dose (p < 0.05).  The overall sample of 182 patients reported a considerably high incidence of hip-related CPSP (60 % at 3 months, 45 % at 6 months).  The authors concluded that USG-FICB in the peri-operative setting may reduce the incidence, intensity and severity of CPSP at 3 and 6 months after hip fracture surgery, providing safe and effective post-operative analgesia.

Furthermore, an UpToDate review on "Lower extremity nerve blocks: Techniques" (Jeng and Rosenblatt, 2020) states that "Peripheral nerve blocks of the lower extremity are used for operative anesthesia and/or postoperative analgesia for a variety of lower extremity surgeries … Femoral nerve block is used to provide anesthesia or postoperative analgesia for surgery of the anterior thigh and knee (e.g., anterior cruciate ligament repair, patella surgery, quadriceps tendon repair) … The fascia iliaca block is an alternative to the femoral nerve block and may more reliably block the lateral femoral cutaneous nerve than the femoral block.  It blocks the sensory innervation of the lateral thigh.  This block does not depend on deposition of local anesthetic (LA) near an individual nerve; instead, it works by spread of the LA in a fascial plane.  Therefore, this block is not performed with nerve stimulation.  It can be done using ultrasound guidance or with an anatomic approach".

Shakya et al (2018) noted that the post-operative pain management in the elderly is challenging due to co-morbidities and change in physiology due to age itself.  This limits the use of medication including pain medication.  The fascia iliaca compartment block has been described in the literature for fracture of femur.  It has also been safely used by non-anesthesiologist.  These investigators did not find any case report of continuous fascia iliaca compartment block published in Nepal.  This was their 1st experience of successful continuous fascia iliaca compartment block in the case of a 89-year old woman with multiple co-morbidities in whom traditional pain medication might be difficult to use.  The authors encouraged the practice of continuous fascia iliaca compartment block, which is both safe and easy to carry out with good results.

Gopal and Krishnamurthy (2018) stated that positioning fracture femur cases for sub-arachnoid block (SAB) is challenging.  Fascia iliaca compartment block (FICB) is low-skilled, helps positioning, and provides analgesia.; and dexmedetomidine (DEX) as an adjuvant prolongs analgesia. In a prospective, randomized, double-blind study, these researchers compared FICB with bupivacaine and bupivacaine with DEX in fracture femur cases with regard to positioning during SAB, duration of analgesia in terms of visual analog scale (VAS), numerical rating scale (NRS), and Patient Satisfaction Score, and evaluated side effects.  A total of 60 fracture femur patients were divided into 2 groups -- Group A: FICB with injection bupivacaine 0.25 % 38 cc + DEX 0.5 μg/kg in 2 cc normal saline (NS) and Group B: FICB with injection bupivacaine 0.25 % 38 cc + 2 cc NS.  Data were analyzed using SPSS 22.0 software.  Categorical data were processed by frequencies and proportions, whereas continuous data were processed by mean standard deviation (MSD).  Chi-square test and independent t-test were used as tests of significance, considering p < 0.05 as statistically significant.  In Group A, mean VAS score at 5 mins was 3.7 ± 0.9; and in Group B it was 4.3 ± 0.7.  Similarly, at 15 mins, mean VAS score in Group A was 0.4 ± 0.6 and in Group B it was 1.9 ± 0.9.  VAS score was significantly high in Group B at 5, 10, and 15 mins.  Mean time to rescue analgesia in Group A was 838.3 ± 82.7 mins and in Group B it was 461.5 ± 36.6 mins, which was significant.  The authors concluded that FICB ensured patient comfort during positioning for SAB and provided post-operative analgesia; and DEX significantly prolonged post-operative analgesia.

The authors stated that the block success with this “feel” technique was sporadic because false “pops” could occur.  Ultrasound (US)-guided technique was essentially the same; however, monitoring of the needle placement and local anesthetic delivery ensured deposition of the local anesthetic into the correct plane.

Femoral Nerve Block for Post-Operative Knee Pain

An UpToDate review on "Lower extremity nerve blocks: Techniques" (Jeng and Rosenblatt, 2019a) states that "Femoral nerve block is used to provide anesthesia or postoperative analgesia for surgery of the anterior thigh and knee (e.g., anterior cruciate ligament repair, patella surgery, quadriceps tendon repair).  Traditionally, this block was also referred to as the "3-in-1" block, wherein high volume of local anesthetic (LA) can block the femoral, lateral femoral cutaneous, and obturator nerves.  This concept was based on the purported existence of a supra-inguinal fluid compartment between the femoral nerve sheath and the lumbar plexus, capable of allowing spread of LA proximally to the lumbar plexus with a single injection at the femoral nerve in the inguinal region.  However, a human cadaver study has shown that a fluid compartment between the femoral nerve sheath and the lumbar plexus does not exist, and several studies have shown that a femoral block does not reliably block the obturator nerve, the lateral femoral cutaneous nerve, or the lumbar plexus.  Since only the femoral nerve is reliably blocked by this technique, we usually now refer to it as the femoral nerve block.  Ultrasound-guided femoral block – The ultrasound transducer is placed in the inguinal crease to locate the hyperechoic femoral nerve, which can be visualized lateral to the hypoechoic pulsatile common femoral artery, superficial to the iliopsoas muscle group, and deep to the fascia lata and fascia iliaca.  An in-plane or out-of-plane approach can be used.  The needle is inserted and the tip placed adjacent to the nerve.  After negative aspiration, 20 to 40 mL of LA is injected in 5 mL increments, with gentle aspiration between injections.  LA should be seen spreading above, below, or circumferentially around the nerve".

Filling of Implantable Intrathecal Pump Reservoir

Maino et al (2018) noted that the localization of the reservoir fill port of intrathecal drug delivery devices (IDDS) could be difficult.  In a prospective, single-center study, these researchers compared the ease of fill port access during the US-guided refill technique with that of the blind refill technique in IDDSs with a raised septum on the pump surface.  Written informed consent was obtained from 19 adult patients undergoing regular refills of their raised septum IDDSs (RS-IDDSs).  The primary outcome was the number of attempts to enter the reservoir fill port with the needle comparing the US-guided technique versus the blind technique.  The number of skin punctures per refill procedure and time to enter the reservoir fill port was secondary outcomes.  For between group comparisons the Friedman test for repeated measures on ranks was used.  A total of 111 refill procedures were assessed in 19 patients over a period of 24 months.  The median number of attempts to enter the reservoir fill port with the needle differed significantly between the US-guided technique and the blind technique (4 [IQR: 1 to 6] versus 1 [IQR: 1 to 3], p = 0.018), in favor of the blind technique.  The median time to enter the reservoir fill port differed significantly between the US-guided technique and the blind technique (58 sec [IQR: 38 to 94] versus 22 sec [IQR: 16 to 40], p < 0.001).  The authors concluded that the findings of this study suggested that for a RS-IDDS, the blind refill technique needed significantly less attempts to enter the reservoir fill port than the US-guided refill technique.

Maino et al (2019) stated that structural differences of IDDSs might have an impact on the efficiency of needle access to the reservoir fill port (RFP).  These investigators examined the efficiency of RFP needle access with an US-guided versus a blind refill technique in IDDSs with a recessed RFP (Recessed-RFP-IDDS).  The primary outcome was the number of attempts needed to enter the RFP with a needle comparing the US-guided technique versus the blind refill technique.  The time to enter the RFP with the needle was a secondary outcome.  These researchers compared the number of attempts between both techniques with the non-parametric Wilcoxon rank sum test.  A total of 14 adult patients underwent a total of 75 refills of their Recessed-RFP-IDDS during a period of 24 months.  The median number of attempts to enter the RFP did not differ significantly between the US-guided technique and the blind refill technique (2.0 (IQR: 1 to 5) versus 1.5 (IQR: 1 to 5.0), p = 0.572).  The median time to enter the RFP with the needle did not differ significantly between both techniques (35.0 sec (IQR: 26.0 to 58.0) versus 41.0 sec (IQR: 25.5 to 46.8), p = 0.878).  The authors concluded that the findings of this study suggested that there was no difference in the RFP needle access efficiency between the US-guided and the blind refill technique in superficially located Recessed-RFP-IDDSs, if performed by experienced practitioners.  However, the study did not address efficiency of the RFP needle access in IDDSs with aberrancy in pump location or refills performed by inexperienced staff.

Singa et al (2020) noted that IDDS are refilled using templates and palpation.  The 2017 Polyanalgesic Consensus Conference recommended US only when reservoir ports are difficult to identify.  These researchers compared procedural outcomes and patient's preference for refill method of IDDS.  Participants were randomized to have their IDDS with US or template using a 2:1 allocation.  The time to reservoir port access, number of needle maneuvers/punctures, pain (NRS 0 to 10), complications, patient satisfaction, and patient refill modality preference, were recorded.  A total of 107 patients underwent 192 refills.  There were 67 template-guided refills and 125 US-guided refills.  No procedural pain (NRS = 0) was reported in 84 % of the US-guided refills compared with 67 % of the template-guided procedures, difference of 17 % (95 % CI: - 3 % to -31 %, p = 0.01).  When adjusted for age, gender, procedure duration, needle sticks, needle maneuvers and refills in the same patient, the OR for a pain-free procedure with US-guidance was 3.1 (95 % CI: 1.3 to 7.2, p = 0.01).  There was no difference between the groups in needle punctures (p = 0.87) or re-directions (p = 0.34).  Following 35/67 (52 %) template-guided procedures, patients stated they preferred the US-guided but following only 12/125 (10 %) of US-guided procedures, patients stated they preferred template-guidance (p < 0.001).  The authors concluded that patients preferred US even though it lengthened the duration of refills compared to template-guided procedures.  Fewer patients experienced procedural pain with US compared with template-guided refills.  No safety issues were observed in either group.  Moreover, these investigators stated that these findings supported further investigations into the use of US guidance for IDDP refills.

Fine-Needle Aspiration for Biopsy of Neck Mass

The American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS)’s clinical practice guideline on “Evaluation of the neck mass in adults” (Pynnonen et al, 2017) stated that the addition of US-guided fine-needle aspiration (FNA) has been shown to increase specimen adequacy: it can be useful when initial palpation-guided FNA is of limited diagnostic utility, and it can improve the diagnostic yield with cystic or necrotic masses by facilitating directed biopsy of the solid component of the cyst.

Ilioinguinal Nerve Block

Wang et al (2016) stated that ultrasound (US)-guided ilioinguinal / iliohypogastric (II/IH) nerve and TAP blocks have been increasingly utilized in patients for peri-operative analgesia.  These researchers conducted a meta-analysis to examine the clinical efficacy of US-guided II/IH nerve or TAP blocks for peri-operative analgesia in patients undergoing open inguinal surgery.  A systematic search was conducted of 7 databases from the inception to March 5, 2015.  Randomized controlled trials (RCTs) comparing the clinical efficacy of US-guided versus landmark-based techniques to perform II/IH nerve and TAP blocks in patients with open inguinal surgery were included.  They constructed random effects models to pool the standardized mean difference (SMD) for continuous outcomes and the odds ratio (OR) for dichotomized outcomes.  US-guided II/IH nerve or TAP blocks were associated with a reduced use of intra-operative additional analgesia and a significant reduction of pain scores during day-stay.  The use of rescue drugs was also significantly lower in the US-guided group.  The authors concluded that the use of US-guidance to perform an II/IH nerve or a TAP block was associated with improved peri-operative analgesia in patients following open inguinal surgery compared to landmark-based methods.

In a prospective, randomized clinical trial, Faiz et al (2019) compared the efficacy of ilioinguinal / iliohypogastric (IINB) nerve block to TAP block in controlling incisional pain after open inguinal hernia repair.  This trial included 90 patients who received either IINB (n = 45) or TAP block (n = 45) using 0.2 % bupivacaine 15 ml under US guidance based on a random assignment in the post-anesthesia care unit (PACU) after having an open repair of inguinal hernia.  Numeric Rating Scale (NRS) scores were recorded immediately following, 4, 8, 12, and 24 hours after completion of the block; NRS scores at rest and during movement were recorded 24, 36, and 48 hours after surgery.  Analgesic satisfaction level was also evaluated by a Likert-based patient questionnaire.  NRS scores were lower in the IINB group compared to the TAP block group both at rest and during movement.  The difference in dynamic pain scores was statistically significant (p = 0.017).  In addition, analgesic satisfaction was significantly greater in the IINB group than the TAP block group (mean score 2.43 versus 1.84, p = 0.001).  Post-operative opioid requirements did not differ between the 2 groups.  The authors concluded that the findings of this study demonstrated that compared to TAP block, local blockade of ilioinguinal and iliohypogastric nerves provided better pain control after open repair of inguinal hernia when both blocks were administered under US guidance.  Greater satisfaction scores also reflected superior analgesia in patients receiving IINB.

Bhatia et al (2019) noted that analgesic efficacy of US-guided TAP block, administered a little more medially, just close to the origin of the transverse abdominis muscle has not yet been examined in patients undergoing unilateral inguinal hernia repair.  These researchers hypothesized that medial TAP block would provide comparable post-operative analgesia to ilioinguinal-iliohypogastric nerve block in inguinal hernia repair patients.  This prospective, randomized trial was conducted in 50 ASA I and II male patients greater than or equal to 18 years of age.  Patients were randomized into 2 groups to receive either pre-incisional ipsilateral US-guided ilioinguinal-iliohypogastric nerve block or medial TAP block, with 0.3 ml/kg of 0.25 % bupivacaine.  The primary objective was post-operative 24-hour analgesic consumption and secondary outcomes included pain scores, time to first request for rescue analgesic and side effects, if any, in the post-operative period.  There was no significant difference in the total post-operative analgesic consumption [group I: 66.04 mg; group II: 68.33 mg (p value 0.908)].  Time to first request for rescue analgesic was delayed, though statistically non-significant (p value 0.326), following medial TAP block, with excellent pain relief observed in 58.3 % patients as opposed to 45.8 % patients in ilioinguinal-iliohypogastric nerve block group.  The authors concluded that medial TAP  block being a novel, simple and easily performed procedure can serve as an useful alternative to ilioinguinal-iliohypogastric nerve block for providing post-operative pain relief in inguinal hernia repair patients.

Samerchua et al (2020) stated that ilioinguinal/iliohypogastric nerve block is commonly performed to control post-herniotomy pain.  The posterior quadratus lumborum block has been recently described as an effective analgesic technique for pediatric low abdominal surgery.  No data were found regarding the use of posterior quadratus lumborum block in comparison with the traditional ilioinguinal/iliohypogastric nerve block in pediatric inguinal surgery.  In a randomized, assessor-blinded study, these researchers compared post-operative analgesic effects between US-guided posterior quadratus lumborum block and ilioinguinal/iliohypogastric nerve block in pediatric inguinal herniotomy.  1- to 7-year-old children scheduled for unilateral open herniotomy were randomly assigned to receive either US-guided posterior quadratus lumborum block with 0.25 % bupivacaine 0.5 ml/kg or US-guided ilioinguinal/iliohypogastric nerve block with 0.25 % bupivacaine 0.2 ml/kg after induction of general anesthesia.  The primary outcome was the proportion of patients who received post-operative oral acetaminophen.  The required fentanyl in the recovery room, 24-hour acetaminophen consumption, success rate of regional blocks, block performance data, block-related complications, post-operative pain intensity, and parental satisfaction were assessed.  This study included 40 patients after excluding 4 cases who were ineligible.  The number of patients who required post-operative oral acetaminophen was significantly lower in the posterior quadratus lumborum block group (15.8 % versus 52.6 %; odds ratio [OR]: 5.9; 95 % confidence interval [CI]: 1.3 to 27.3; p = 0.022).  The pain scores at 30 mins, 1, 2, 6, 12, and 24 hours were similar between groups.  There was no evidence of between-group differences in block performance time, the number of needle passes, block-related complications, and parental satisfaction.  The authors concluded that the posterior quadratus lumborum block with 0.25 % bupivacaine 0.5 ml/kg provided better pain control than the ilioinguinal/iliohypogastric nerve block with 0.25 % bupivacaine 0.2 ml/kg after open herniotomy in children.  The US guidance technique for the posterior quadratus lumborum block was safe and as simple as the US-guided ilioinguinal/iliohypogastric nerve block for pediatric patients.

Injection of the Piriformis Ligament

An UpToDate review on “Approach to hip and groin pain in the athlete and active adult” (Johnson, 2023) stated that “Treatment begins with physical therapy involving strengthening of the pelvic and hip region and stretching of the piriformis.  Appropriate analgesics for neuropathic pain are taken as needed.  Physical therapy is effective in the majority of cases.  Ultrasound-guided glucocorticoid injections have been beneficial in some cases, and botulinum toxin injections have also been used.  Surgery (typically a piriformis tenotomy) may be considered if symptoms are debilitating and persist despite appropriate nonoperative therapy”.

Injection of Sub-Gluteal Bursa

StatPerals’ webpage on “Greater trochanteric bursa injection” (Le and Shah, 2023) stated that several bursae around the greater trochanter co-facilitate abduction with the abductor tendons; these include the sub-gluteus maximus, sub-gluteus medius, and sub-gluteus minimus bursae.  Colloquially, the "trochanteric bursa" refers to the sub-gluteus maximus bursa located lateral to the greater trochanter between the gluteus maximus and gluteus medius muscles and deep to the ITB and fascia lata.  Injections of the trochanteric bursa can be carried out without image guidance based on anatomic landmarks or under US or fluoroscopic guidance; US guidance provides a reliable and safe modality to identify tendons and bursae, which may improve injection accuracy compared to a landmark-based method.  Furthermore, it allows visualization of the needle tip and spread of the injectate.  The sue of fluoroscopy or US may aid in directing needle placement and confirm intra-bursal injection; however, there is little evidence that imaging modalities improve clinical outcomes.  A multicenter randomized trial comparing landmark-based and fluoroscopy-guided corticosteroid injections reported no significant difference in pain scores at rest and with activity 1 month after injection.  A study comparing the accuracy of landmark-based injections against US-guided injections in cadavers showed that US-guided injections had higher accuracy concerning injection into the greater trochanter bursa.  Image-guided injections should be considered for patients who failed to get pain relief with a landmark-based injection or those with imaging demonstrating bursal inflammation.

Intercostobrachial Nerve Block

Satapathy and Coventry (2011) noted that the axillary approach to brachial plexus blockade provides satisfactory anesthesia for elbow, forearm, and hand surgery and also provides reliable cutaneous anesthesia of the inner upper arm including the medial cutaneous nerve of arm and intercostobrachial nerve, areas often missed with other approaches.  In addition, the axillary approach remains the safest of the 4 main options, as it does not risk blockade of the phrenic nerve, nor does it have the potential to cause pneumothorax, making it an ideal option for day case surgery.  Historically, single-injection techniques have not provided reliable blockade in the musculocutaneous and radial nerve territories, but success rates have greatly improved with multiple-injection techniques whether using nerve stimulation or US guidance.  Complete, reliable, rapid, and safe blockade of the arm is now achievable.  The authors concluded that axillary nerve block is a safe and effective regional anesthetic technique suitable for a wide variety of procedures, for both in-patient and out-patient care]; US guidance has allowed improved efficacy with smaller volumes of local anesthetic.  Direct visualization of block performance and local anesthetic injection, though inherently safer, does not completely eliminate the risk of intra-vascular and intra-neural injection, and care should be continually exercised using standard safety precautions of slow, careful, fractionated injections to prevent and minimize the risks associated with the technique.

Thallaj et al (2015) tested the hypothesis that identification and blockade of the intercostobrachial nerve (ICBN) can be achieved under US guidance using a small volume of local anesthetic.  A total of 28  adult male volunteers were examined at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia from November 2012 to September 2013.  Intercostobrachial nerve blockade was performed using 1-ml of 2 % lidocaine under US guidance.  A sensory map of the blocked area was developed relative to the medial aspect of the humeral head.  The ICBN appeared as a hyper-echoic structure.  The nerve diameter was 2.3 ± 0.28 mm, and the depth was 9 ± 0.28 mm.  The measurements of the sensory-blocked area relative to the medial aspect of the humeral head were as follows: 6.3 ± 1.6 cm anteriorly; 6.2 ± 2.9 cm posteriorly; 9.4 ± 2.9 cm proximally; and 9.2 ± 4.4 cm distally.  Intercostobrachial nerve blockade using 1-ml of local anesthetic was successful in all cases.  The authors concluded that this study described the sonographic anatomical details of the ICBN and its sensory distribution to successfully perform selective US-guided ICBN blockade.  These researchers stated that this technique can be used as a supplemental block for upper limb anesthesia.  They recommended further studies to support and apply these findings to improve patient care.

Wijayasinghe et al (2016) stated that persistent pain after breast cancer surgery (PPBCS) affects 25 to  60 % of breast cancer survivors and damage to the ICBN has been implicated as the cause of this predominantly neuropathic pain.  Local anesthetic blockade of the ICBN could provide clues to pathophysiological mechanisms as well as aiding diagnosis and treatment of PPBCS but has never been attempted.  In a prospective, pilot study, these researchers examined the feasibility of ICBN blockade and evaluated its effects on pain and sensory function in patients with PPBCS.  This trial was performed in 2 parts: Part 1 determined the sonoanatomy of the ICBN and part 2 examined the effects of the US-guided ICBN blockade in patients with PPBCS.  Part 1: 16 unoperated, pain-free BC patients underwent systematic ultrasonography to establish the sonoanatomy of the ICBN.  Part 2: 6 patients with PPBCS who had pain in the axilla and upper arm were recruited for the study.  Summed pain intensity (SPI) scores and sensory function were measured before and 30 mins after the block was administered.  SPI is a combined pain score of numerical rating scale (NRS) at rest, movement, and 100 kPa pressure applied to the maximum point of pain using pressure algometry (max = 30).  Sensory function was measured using quantitative sensory testing (QST), which consisted of sensory mapping, thermal thresholds, supra-threshold heat pain perception as well as heat and pressure pain thresholds.  The ICBN block was performed under US-guidance and 10 ml 0.5 % bupivacaine was injected.  Outcome measures included the ability to perform the ICBN block and its analgesic and sensory effects.  Only the second intercostal space could be observed on US, which was adequate to perform the ICBN block.  The mean difference in SPI was -9 NRS points (95 % confidence interval [CI]: -14.1 to -3.9; p = 0.006).  All patients had pre-existing areas of hypoesthesia that decreased in size in 4/6 patients following the block.  The authors successfully blocked the ICBN using US-guidance and demonstrated an analgesic effect in patients in PPBCS calling for placebo-controlled studies.  The main drawback of this pilot study was its small sample size (n = 6), but despite this, a statistically significant effect was observed.  These researchers stated that the premise of this study was to examine the feasibility of a randomized controlled trial (RCT) and these findings suggested that a RCT is needed to determine the role of ICBN blockade in PPBCS.

Magazzeni et al (2018) stated that for superficial surgery of antero-medial and postero-medial surfaces of the upper arm, the medial brachial cutaneous nerve (MBCN) and the ICBN must be selectively blocked, in addition to an axillary brachial plexus block.  Ina randomized study, these researchers compared efficacy of US-guided (USG) versus conventional block of the MBCN and the ICBN.  A total of 84 patients, undergoing upper limb surgery, were randomized to receive either USG (n = 42) or conventional (n = 42) block of the MBCN and the ICBN with 1 % mepivacaine.  Sensory block was evaluated using light-touch on the upper and lower half of the antero-medial and postero-medial surfaces of the upper arm at 5, 10, 15, 20 mins after nerve blocks.  The primary outcome was the proportion of patients who had no sensation in all 4 regions innervated by the MBCN and the ICBN at 20 mins.  Secondary outcomes were onset time of complete anesthesia, volume of local anesthetic, tourniquet tolerance, and quality of US images.  In the USG group, 37 patients (88 %) had no sensation at 20 mins in any of the 4 areas tested versus 8 patients (19 %) in the conventional group (p < 0.001).  When complete anesthesia was obtained, it occurred within 10 mins in more than 90 % of patients, in both groups.  Mean total volumes of local anesthetic used for blocking the MBCN and the ICBN were similar in the 2 groups; US images were of good quality in only 20 (47.6 %) of 42 patients; 41 patients (97.6 %) who received USG block were comfortable with the tourniquet versus 16 patients (38.1 %) in the conventional group (p < 0.001).  The authors concluded that US guidance improved the efficacy of the MBCN and ICBN blocks.

Inter-Digital Neuroma Injection

Morgan et al (2014) stated that Morton's neuroma (MN) is a frequently painful condition of the forefoot, causing patients to seek medical care to alleviate symptoms.  A plethora of therapeutic options is available, some of which include injection therapies.  Researchers have examined injection therapy for MN, and the evidence base has been augmented with methods that use diagnostic US as a vehicle to deliver the injectate under image guidance for additional accuracy.  To-date, there appeared to be no consensus that US-guided injections provided better therapeutic outcomes than non-guided injections for the treatment of MN.  In a systematic review, these researchers identified 13 key studies using pre-determined inclusion and exclusion criteria, which then underwent methodological quality assessment using a pre-tested Quality Index.  A narrative synthesis of the review findings was presented in light of the heterogeneity of the data from the extraction process.  This systematic review provided an argument that US guidance could produce better short- and long-term pain relief for corticosteroid injections, could reduce the need for additional procedures in a series of sclerosing alcohol injections, could reduce the surgical referral rate, and could add efficacy to a single injection.  The authors concluded that US guidance should be considered for injection therapy in the management of MN.

In a randomized, evaluator-blinded study, Santiago et al (2019) compared the effectiveness of blind and US-guided injection for Morton's neuroma (MN) to determine which is more appropriate as the initial procedure in conservative treatment.  Of the 56 included patients, 27 were assigned to the blind group (A) and 29 to the US-guided group (B).  Injection includes 1-ml of 2 % mepivacaine and 40-mg of triamcinolone in each web space with MN.  The included patients were examined clinically by VAS score and the Manchester Foot Pain and Disability Score (MFPDS).  The follow-up was carried out at 15 days, 1 month, 45 days, 2 months, 3 months, and 6 months after the initial injection.  No differences in age or clinical measurements were found at presentation between group A and group B.  At the follow-up, the US-guided group showed greater symptomatic relief at several stages of the follow-up: 45 days (VAS 3.0 ± 0.5 versus 5.5 ± 0.5, p = 0.001; MFPDS: 32.2 ± 1.8 versus 38.8 ± 2.0, p = 0.018), 2 months (VAS: 3.1 ± 0.5 versus 5.6 ± 0.5, p = 0.002; MFPDS: 31.5 ± 1.9 versus 38.5 ± 2.1, p = 0.020) and 3 months (VAS: 3.1 ± 0.4 versus 5.2 ± 0.6, p = 0.010; MFPDS: 31.2 ± 1.9 versus 37.7 ± 2.4, p = 0.047).  The authors concluded that injection of MN under US guidance provided a statistically significant improvement at some stages of the follow-up (45 days, 2 and 3 months), compared with blind injection.  However, there were no significant differences between guided and non-guided injections at other time-points (15 days, 1 month, and 6 months).

In a prospective, follow-up study of a previous RCT, Hay et al (2021) examined the medium-term results of corticosteroid injections for MN.  A total of 45 MNs in 36 patients were injected with a single corticosteroid injection either with or without US guidance.  As the results of the RCT showed no difference in outcomes between techniques, the data were pooled for this study.  Questionnaires were sent out and responses were collected via mail or telephone interview.  Results were available in 42 out of 45 MNs.  There was a sex split of 68 % female/32 % male with a mean age of 62.6 years (SD, 12 years).  At mean follow-up of 4.8 years (SD, 0.91 years), the original corticosteroid injection remained effective in 36 % (n = 16) of the patients.  In these cases, the VAS pain score (p < 0.001) and Manchester-Oxford Foot Questionnaire Index (MOxFQ Index) (p = 0.001) remained significantly better than pre-intervention scores.  The remaining cases underwent either a further injection or surgery; 55 % of the 11 MNs that received a 2nd injection continued to be asymptomatic in the medium-term.  A total of 44 % (n = 20) of the initial cohort underwent surgical excision by the medium-term follow-up.  The VAS score, MOxFQ Index, and satisfaction scale score across all groups were not significantly different.  The authors concluded that corticosteroid injections for MN remained effective in over a 1/3 of cases for up to almost 5 years.  A positive outcome at 1 year following a corticosteroid injection was reasonably predictive of a prolonged effect from the injection.

In a systematic review, Choi et al (2021) examined the effects of corticosteroid injections on MN using an algorithmic approach to evaluate the methodological quality of reported studies using a structured critical framework.  Several electronic databases were searched for articles published until April 2020 that examined the outcomes of corticosteroid injections in patients diagnosed with MN.  Data search, extraction, analysis, and quality assessments were carried out according to the PRISMA guidelines, and clinical outcomes were evaluated using various outcome measures.  With 3 to 12 months of follow-up, corticosteroid injections provided satisfactory outcomes according to Johnson satisfaction scores except in 2 studies; VAS scores showed maximal pain reduction between 1 week and 3 months after injection.  These researchers found that 140 subjects out of 469 (29.85 %) eventually underwent surgery after receiving corticosteroid injections due to persistent pain.  The authors concluded that corticosteroid injections showed a satisfactory clinical outcome in patients with Morton's inter-digital neuroma although almost 30 % of the included subjects eventually underwent operative treatment.  Their recommendation for future research included using more objective outcome parameters, such as foot and ankle outcome scores or foot and ankle ability measures.  Moreover, studies on the safety and effectiveness of multiple injections at the same site are highly necessary.

These researchers also noted that in their review, injections carried out under US guidance were reported in 5 studies, while blind injections were carried out in 4 articles.  They also found 2 RCTs comparing US-guided injections with blind injections.  However, these investigators thought a meta-analysis of these studies was impossible as the characteristics of the selected studies were totally heterogeneous with regard to the injected agent, outcome parameters, outcome measurement timing, number of injections, and follow-up period.  With current data, the authors recommended the use of US depending on the surgeon's experience and confidence; US guidance may not be necessary if the surgeon can ensure solid and constant results with blind injection.

Klontzas et al (2021) stated that MN is a painful lesion of the interdigital nerve, usually at the 3ird intermetatarsal space, associated with fibrotic changes in the nerve, microvascular degeneration, and deregulation of sympathetic innervation.  Patients usually present with burning or sharp metatarsalgia at the dorsal or plantar aspect of the foot.  The management of MN starts with conservative measures, usually with limited efficacy, including orthotics and anti-inflammatory medication.  When conservative treatment fails, a series of minimally invasive US-guided procedures can be used as 2nd-line treatments prior to surgery.  Such procedures include infiltration of the area with a corticosteroid and local anesthetic, chemical neurolysis with alcohol or radiofrequency (RF) thermal neurolysis.  Ultrasound aids in the accurate diagnosis of MN and guides the afore-mentioned treatment, so that significant and potentially long-lasting pain reduction can be achieved.  In cases of initial treatment failure, the procedure can be repeated, usually leading to the complete remission of symptoms.  The authors concluded that US is the imaging modality of choice for the diagnosis of MN, while also enabling imaging-guided treatment.  US-guided procedures including corticosteroid infiltration, chemical neurolysis and RF thermal neurolysis are viable alternatives to surgical treatment, offering high rates of complete remission of symptoms in patients when conservative management has failed, prior to surgery.

Sconfienza et al (2022) stated that clarity regarding accuracy and effectiveness for interventional procedures around the foot and ankle is lacking.  Consequently, a board of 53 members of the Ultrasound and Interventional Subcommittees of the European Society of Musculoskeletal Radiology (ESSR) reviewed the published literature to examine the evidence on image-guided musculoskeletal interventional procedures around this anatomical region.  These investigators reported the findings of a Delphi-based consensus of 53 experts from the ESSR who reviewed the published literature for evidence on image-guided interventional procedures offered around foot and ankle in order to derive their clinical indications.  Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence.  Consensus was considered strong when greater than 95 % of experts agreed with the statement or broad when greater than 80 % but less than 95 % agreed.  The results of the Delphi-based consensus were used to draft the paper that was shared with all panel members for final approval.  A list of 16 evidence-based statements on clinical indications for image-guided musculoskeletal interventional procedures in the foot and ankle were drafted after a literature review.  The highest level of evidence was reported for 4 statements, all receiving 100 % agreement.  The authors concluded that according to this consensus, image-guided interventions should not be considered a 1st-level approach for treating Achilles tendinopathy, while US guidance is strongly recommended to improve the efficacy of interventional procedures for plantar fasciitis and MN, particularly using platelet-rich plasma and corticosteroids, respectively.

Interscalene Nerve Block

Rajpal et al (2016) noted that post-operative neurologic symptoms after interscalene block and shoulder surgery have been reported to be relatively frequent.  These investigators evaluated 300 patients for neurologic symptoms after low-volume, US-guided interscalene block and arthroscopic shoulder surgery (ASS).  Patients underwent US-guided interscalene block with 16 to 20 ml of 0.5 % bupivacaine or a mix of 0.2 % bupivacaine/1.2 % mepivacaine solution, followed by propofol/ketamine sedation for ambulatory ASS.  Patients were called at 10 days for evaluation of neurologic symptoms, and those with persistent symptoms were called again at 30 days, at which point neurologic evaluation was initiated.  Details of patient demographics and block characteristics were collected to assess any association with persistent neurologic symptoms; 6 of 300 patients reported symptoms at 10 days (2 %), with 1 of these patients having persistent symptoms at 30 days (0.3 %).  This was significantly lower than rates of neurologic symptoms reported in pre-US investigations with focused neurologic follow-up and similar to other studies performed in the US era.  There was a modest correlation between the number of needle re-directions during the block procedure and the presence of post-operative neurologic symptoms.  The authors concluded that US guidance of interscalene block with 16- to 20-ml volumes of local anesthetic solution resulted in a lower frequency of post-operative neurologic symptoms at 10 and 30 days as compared with investigations in the pre-US period.

Fuzier et al (2016) performed a cross-sectional survey study on French practice in US-guided regional anesthesia.  A questionnaire (demographic data, assessment of the likely benefits of US, and its use in daily practice: blocks and hygiene) was emailed to all members of the French-speaking association of anesthesiologists involved in regional anesthesia.  The questionnaire was filled out and returned by 634 experienced anesthesiologists.  An US machine was available in 94 % of cases; US-guided regional anesthesia has become the gold standard technique for 3/4 of responders.  Interscalene, popliteal sciatic and femoral nerve blocks were performed by more than 90 % of responders, most frequently under US supervision.  Conversely, US guidance was rarely used for spinal or deep nerve blocks.  A specific sterile sheath was used in only 43 % of cases.  The authors concluded that the present study confirmed that US guidance has gained in popularity for many superficial, but not deep, regional anesthesia procedures in France.

Kolny et al (2017) stated that interscalene brachial plexus block (ISBPB) is an effective regional anesthesia technique for shoulder surgeries.  The superiority of the popular US-guided blocks over peripheral nerve stimulator (PNS)-confirmed blocks remains unclear.  In this study, the efficacy of these different block techniques was compared.  This prospective, randomized, clinical study included 109 patients (American Society of Anesthesiologists [ASA] grades I-III) who receive 20 ml 0.5 % ropivacaine with US-guided blocks (U group), PNS-confirmed blocks (N group), or US-guided and PNS-confirmed blocks (dual guidance; NU group) for elective shoulder arthroscopy.  Block onset time, duration, and effectiveness on the Lovett rating scale (LRS) were assessed.  There was no statistically significant inter-group difference in duration of block performance, irrespective of the technique (p = 0.232).  Onset time of complete warmth sensation loss (p < 0.001) and muscle strength abolition (p < 0.001) was significantly longer and mean LRS score distribution was significantly higher in the N group than in the other groups (p < 0.001).  These findings showed a statistically significant correlation between the performance of the used block technique and the necessity of conversion to general anesthesia because of insufficient block in the N group (58.54 %) than in the U (24.44 %) and NU (19.57 %) groups.  The authors stated that in a majority of studies, US guidance tended to be superior to PNS assistance for ISBPB.  Compared to PNS assistance, US guidance led to faster onset time of ISBPB, lowered the rate of conversions to general anesthesia, and improved LRS scores.  They concluded that PNS-confirmed needle placement was not necessary to ensure effectiveness of US-guided blocks as evidenced by the low rate of conversion to general anesthesia in this study.  Nevertheless, the dual guidance technique (US guidance and PNS confirmation) was recommended to reduce the risk of complications and might be considered the regional anesthesia of choice for shoulder surgery.

In a RCT, Woo et al (2018) examined if ISBPB using a lower concentration of local anesthetic would reduce the incidence of post-thoracotomy ipsilateral shoulder pain with assessment of pulmonary function in patients who underwent a lung lobectomy.  A total of 44 patients who underwent a lung lobectomy were randomly assigned to either the control or the interscalene block (ISB) group.  Single-shot ISB on the surgical site side was performed using ropivacaine 10-ml 0.25 % including 5-mg dexamethasone under US guidance in the ISB group.  Lobectomy and continuous paravertebral block were performed under general anesthesia.  The presence of ipsilateral shoulder pain and post-operative adverse events (AEs) were assessed.  Pulmonary function tests were performed pre-operatively, the day after surgery, and the day after removing the chest tube.  The incidence of ipsilateral shoulder pain was significantly lower in the ISB group than in the control group (54.5 % versus 14.3 %, p = 0.006) with an overall incidence of 34.9 %.  Post-operative AEs were similar between the groups, with no patients presenting symptoms of respiratory difficulty.  Significant reductions in pulmonary function were observed in all patients after lobectomy; however, no significant difference in any of the pulmonary function test variables was observed post-operatively between the groups.  The authors concluded that ISB using 10-ml of 0.25 % ropivacaine including 5-mg dexamethasone reduced the incidence of post-thoracotomy ipsilateral shoulder pain and did not result in additional impairment of pulmonary function.

In a prospective, randomized, clinical study, Stasiowski et al (2018a) evaluated the effect of the ISBPB on the occurrence rate of Horner's syndrome.  A total of 108 randomly selected patients of ASA I-III status were scheduled for elective shoulder arthroscopy.  The patients received 20 ml of 0.5 % ropivacaine either with US-guided ISBPB (U), PNS-confirmation ISBPB (N), or US-guided, PNS-confirmed ISBPB (dual guidance; NU).  These researchers observed that Horner's syndrome developed in 12 % of the N group, 6 % of the NU group, and 9 % of the U group.  The differences in the rates were not statistically significant (p = 0.616).  Regardless of the technique used to induce ISBPB, this study did not demonstrate any particular anthropometric parameter that pre-disposed patients to the development of Horner's syndrome.  Interestingly, these findings showed that NU patients with Horner's syndrome were significantly younger than NU patients without Horner's syndrome.  The authors concluded that the precision of ISBPB by use of the dual guidance technique may reduce the rate of Horner's syndrome.  The higher water concentration in the prevertebral spaces of younger patients may create better conditions for the diffusion of ropivacaine, which may result in a statistically significant higher Horner's syndrome rate.

In a prospective, randomized, clinical study, Stasiowski et al (2018b) examined the influence of anthropometric parameters and ISBPB on the quality of post-operational analgesia.  A total of 109 randomly selected patients of ASA I-III status were scheduled for elective shoulder arthroscopy.  Reasons for non-inclusion were as follows: neurological deficit in the upper arm; allergies to amide Las; coagulopathy; and pregnancy.  Patients were divided into 3 groups – group U, group N, or group NU.  These researchers observed that the studied groups did not differ in mean time of sensory and motor block terminations and, surprisingly, in each group in individual cases the sensory block lasted up to 890 to 990 mins providing satisfactory long-lasting post-operational analgesia in patients receiving ISBPB.  These investigators observed a negative correlation between body mass index (BMI) and termination of the motor block and a positive correlation between age and termination of the sensory block in group U in comparison with the 2 other groups.  They found a positive correlation between the male gender and termination of the motor block in patients in group N in comparison with 2 other groups.  The authors concluded that in this study, patients received satisfactory analgesia in the post-operational period no matter what technique was used regardless of their age, gender or potentially uncommon anthropometry.

An UpToDate review on “Shoulder dislocation and reduction” (Sherman, 2022) states that “Ultrasound guided interscalene block is another acceptable method for controlling pain for shoulder reduction.  In a randomized trial of 60 patients, this approach led to shorter lengths of stay in the emergency department compared to procedural sedation.  In another randomized trial involving 42 patients, those given an interscalene block required less 1-on-1 patient monitoring and experienced no significant differences in complication rates, pain, or overall satisfaction”.

Long Head of the Biceps Injection for the Treatment of Tendinosis of the Biceps

In a prospective, single-blinded, pilot study, Gazzillo et al (2011) examined the accuracy of palpating the long head of the biceps tendon (LHBT) within the inter-tubercular groove with the use of ultrasonographic (US) localization as a gold standard.  A total of 25 male and female asymptomatic volunteers aged 24 to 41 years (mean of 30.9 ± 4.3 years) with body mass indices (BMI) of 19.3 to 36.3 kg/m(2) (23.84 ± 4.8 kg/m(2)) were included in this study.  Three examiners of differing experience (a sports medicine board-certified staff physician, a sports medicine fellow, and a physical medicine and rehabilitation resident) identified the LHBT location in the inter-tubercular groove via palpation on a subject in the supine position and marked its location by taping an 18-G Tuohy needle to the skin overlying the groove.  The examiner order was randomized.  A 4th examiner who was blinded to the palpation order assessed the previous examiner's palpation accuracy by comparing the needle position to the US-determined tendon position.  Needle placement in relation to the inter-tubercular groove was graded as being within the groove, medial to the groove, or lateral to the groove.  In the latter 2 cases, the distance from the needle to the closest groove edge was recorded.  Overall accuracy rate was 5.3 % (4/75), ranging from 0 % (0/25) for the resident to 12 % (3/25) for the fellow (p ≤ 0.007 for inter-examiner differences).  All missed palpations were localized medial to the inter-tubercular groove by an average of 1.4 ± 0.5 cm (range of 0.3 for the fellow to 3.5 cm for the resident).  The authors concluded that based on the current methodology, clinicians have a tendency to localize the inter-tubercular groove medial to its actual location.  Consequently, clinicians should exercise caution when relying on clinical palpation to either diagnose a biceps tendon disorder or perform a bicipital tendon sheath injection.  When clinically indicated, US guidance can be used to accurately identify the LBHT within the inter-tubercular groove.

In a prospective randomized, comparative study, Yiannakopoulos et al (2020) compared accuracy, patient discomfort, and clinical outcome of US-guided versus palpation-guided corticosteroid injections to the bicipital groove in patients with LHB tendinosis.  A total of 44 patients with primary LHB tendinosis were randomized into 2 groups (group A, n = 22; group B, n = 22).  All patients underwent treatment with a single corticosteroid injection to the bicipital groove.  Injections in group A were performed under US-guidance, while in group B using a palpation-guided technique.  The duration of each procedure was recorded.  To assess accuracy, US examination was performed in both groups after injection.  Patient discomfort was evaluated with visual analog scale (VAS) for pain.  The clinical outcome was assessed comparing the VAS, the Single Assessment Numeric Evaluation (SANE) score and the QuickDASH score before treatment and after 4 weeks and 6 months.  The mean duration of the procedure was 64 ± 6.87 seconds in group A and 81.91 ± 8.42 seconds in group B (p < 0.001).  Injection accuracy in group A was 100 % and in group B 68.18 %.  Discomfort was lower in group A, as compared to group B (22.10 versus 35.50; p < 0.001).  Symptoms, as measured by VAS, SANE and QuickDASH scores, improved in both groups at 4 weeks and 6 months (p < 0.05).  Superior clinical improvement was recorded in group A in both time-points (p < 0.05).  The authors concluded that corticosteroid injections were an effective treatment for primary LHB tendinosis.  Under US guidance, injections to the bicipital groove were faster and produced lower discomfort.  Superior accuracy and clinical outcomes can be achieved using the US-guided technique.  Level of Evidence = II.

Furthermore, an UpToDate review on “Biceps tendinopathy and tendon rupture” (Simons and Dixon, 2021) states that “Musculoskeletal ultrasound [US] appears to have high sensitivity and specificity for identifying normal tendons and complete tears of the LHBT.  Accuracy is more limited with partial tears and other tendon pathology (e.g., tendinopathy) … As the initial treatment of both LHBT tendinopathy and rupture is typically conservative, advanced diagnostic imaging plays a limited role in the initial workup.  Ultrasound enables the trained clinician to evaluate tendons while they are in motion and to compare them with the contralateral shoulder at the bedside.  Ultrasound has high sensitivity and specificity for complete tears of the LHBT”.

Needle Placement, Lavage, and Debridement of Calcific Tendinosis of the Shoulder

Gatt et al (2014) carried out a systematic review to examine the outcomes and complications of ultrasound (US)-guided barbotage (repeated injection and aspiration) for calcific tendonitis of the shoulder.  They performed a literature search of the Medline, Embase, and Cochrane databases using all relevant keywords found 1,454 original articles.  After removal of duplicates and application of inclusion criteria, 13 original articles were selected for review.  Articles that used fluoroscopic guidance rather than US guidance were excluded from the review.  All studies analyzed except 1 were case series, with no comparative studies being available.  A total of 13 articles with a total of 908 patients were analyzed.  In all articles reviewed, the authors reported a good clinical outcome, with many achieving marked improvement in clinical scores or overall satisfaction with the treatment.  The authors concluded that US-guided barbotage is a safe technique, with a high success rate and low complication rate.  There was no evidence assessing its effectiveness compared with other major treatment modalities; a randomized trial comparing US-guided barbotage, extracorporeal shock wave therapy (ESWT), and arthroscopic calcific deposit excision would be of great value.  However, while awaiting such a trial, on the basis of the results of this systematic review, these investigators recommended US-guided barbotage.

Murray et al (2020) noted that injection of steroid and anesthetic into the greater trochanteric bursa is commonly performed for trochanteric bursitis, gluteus medius/minimus tendinopathy, or as a part of a barbotage procedure for gluteus medius or minimus calcific tendinosis.  Trochanteric bursal injection is widely performed both with and without image guidance; and is typically viewed as low-difficulty; however optimum needle tip position can be challenging.  The authors discussed a simple dynamic US-guided technique to aid the practitioner in optimal needle placement.

Lanza et al (2021) compared the outcome of US-guided percutaneous irrigation of calcific tendinopathy (US-PICT) of the rotator cuff in patients with or without previous external shockwave therapy.  These researchers analyzed all patients treated with US-PICT from March 1, 2016, to October 1, 2019, with shoulder pain refractory to conservative management for rotator cuff calcific tendinopathy, diagnosed with US.  Each patient was examined using the Constant-Murley Score (CMS) questionnaire (score 0 to 100) before and after treatment.  These investigators tested CMS differences using the Mann-Whitney U (Wilcoxon rank-sum) test in the 2 groups.  US-PICT was carried out placing 2 or multiple 14G needles, according to the calcification size, inserted under US guidance to create a circuit of irrigation in the calcified tendon.  NaCl solution at 38 °C was then injected from the entry needle in a variable amount to hydrate and fragment the calcification, finally allowing for its expulsion through the exit needle.  All patients also received an intra-bursal steroid injection.  From 2016 to 2019, a total of 72 US-PICT treatments were performed on 70 patients (women = 46; men = 26) with a mean age of 49.7 years (SD = 8.7.  33 (47 %) underwent previous ESWT, while 37 (53 %) had no previous treatments.  No treatment-related complications were observed.  Follow-up was averagely 14.4 months (median of 11.6, SD = 11.9, range of 1 to 45); 37 patients had a follow-up shorter than 12 months (1 to 11.6); 35 patients were visited after more than 1 year (12.2 to 45.6).  Before treatment, the mean CMS was 35 (SD = 21); after treatment, it reached 75.4, with an average CMS improvement of 40.3 points (SD = 23.7, p < 0.001).  The comparison of improvement between the ESWT and non-ESWT group yielded no significant difference (p = 0.3).  The authors concluded that US-PICT of the rotator cuff was an effective procedure to reduce shoulder pain and increase mobility in patients with calcific tendinopathy, both in short- and long-term time intervals.  Previous unsuccessful ESWT does not affect the outcome of US-PICT.

Bechay et al (2020) stated that calcific tendinopathy of the shoulder involves calcification and degeneration of the rotator cuff tendon near its insertion point on the greater tuberosity.  These researchers analyzed recent literature evaluating the clinical outcomes of non-operative and operative treatment for calcific tendinopathy of the shoulder.  Conservative management, extracorporeal shockwave therapy (ESWT), US-guided percutaneous irrigation of calcific tendinopathy (US-PICT), and surgical intervention were reviewed.

Louwerens et al (2020) compared clinical and radiographic outcomes after treatment with standardized high-energy ESWT)and US-guided needling (UGN) in patients with symptomatic calcific tendinitis of the rotator cuff who were non-responsive to conservative treatment.  The study was designed as a randomized controlled trial (RCT).  The ESWT group received ESWT (2,000 pulses, energy flux density 0.35 mJ/mm2) in 4 sessions with 1-week intervals.  UGN was combined with a corticosteroid US-guided subacromial bursa injection.  Shoulder function was assessed at standardized follow-up intervals (6 weeks and 3, 6, and 12 months) using the Constant Murley Score (CMS), the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and visual analog scale (VAS) for pain and satisfaction.  The size, location, and morphology of the deposits were evaluated on radiographs.  The a priori sample size calculation computed that 44 participants randomized in each treatment group was needed to achieve a power of 80 %.  A total of 82 patients were treated (56 women, 65 %; mean age of 52.1 ± 9 years) with a mean baseline CMS of 66.8 ± 12 and mean calcification size of 15.1 ± 4.7 mm; 1 patient was lost to follow-up.  At 1-year follow-up, the UGN group showed similar results as the ESWT group with regard to the change from baseline CMS (20.9 versus 15.7; p = 0.23), DASH questionnaire (-20.1 versus -20.7; p = .78), and VAS for pain (-3.9 and -2.6; p = 0.12).  The mean calcification size decreased by 13 ± 3.9 mm in the UGN group and 6.7 ± 8.2 mm in the ESWT group (p = 0.001).  In total, 22% of the UGN and 41 % of the ESWT patients received an additional treatment during follow-up because of persistent symptoms.  The authors conclude d that this RCT compared the clinical and radiographic results of UGN and high-energy ESWT in the treatment of calcific tendinitis of the rotator cuff.  Both techniques were successful in improving function and pain, with high satisfaction rates after 1-year follow-up; however, UGN was more effective in eliminating the calcific deposit, and the amounts of additional treatments was greater in the ESWT group.  Level of evidence = II.

Vassalou et al (2021) identified prognostic factors affecting the clinical outcome in patients treated with rotator cuff US-PICT by evaluating the degree of calcium removal, the size and consistency of calcific deposits, and baseline level of shoulder pain and functionality.  From January 2017 to December 2019, a total of 79 patients (23 men, 56 women; mean age of 45.7 years) who underwent US-PICT were prospectively enrolled.  The calcifications' location, consistency, and size were evaluated.  For US-PICT, local anesthesia, lavage of calcific material, and intra-bursal steroid injection were performed.  The degree of calcium removal was graded as total/partial.  Shoulder pain and functionality were assessed with the visual analog scale (VAS) in all and Constant score (CS) in a subset of patients, respectively, at 4 time-points.  Mann-Whitney U test, Fisher's test, and linear and binary logistic regression were utilized for analysis.  Pain improvement correlated with the presence of larger calcifications and lower baseline VAS score, at 1 week (p = 0.001, p < 0.001, respectively) and 1 year (p < 0.001, p = 0.002, respectively).  Improved functionality correlated with total calcification retrieval, higher baseline CS, and fluid/soft calcific consistency at 1 week (p = 0.013, p = 0.003, p = 0.019, respectively).  Increased calcification size, cystic appearance, and lower baseline VAS scores independently predicted complete pain resolution at 1 year.  The authors concluded that large calcifications and low-grade pain at baseline correlated with short- and long-term pain improvement.  The degree of calcium removal did not impact pain or functional improvement beyond 1 week.  Increased calcification size, cystic appearance, and low-grade baseline pain predicted complete pain recovery at 1 year.

Key points: 

  • The presence of larger calcifications and lower-grade baseline pain appeared to correlate with pain improvement at 1 week and 1 year after US-guided irrigation of rotator cuff calcific tendinopathy (US-PICT).
  • Total calcification retrieval, less affected baseline shoulder functionality, and presence of fluid/soft consistency of calcific deposits appeared to correlate with improved shoulder functionality at 1-week post-treatment.
  • Baseline pain intensity and calcifications' morphologic characteristics, but not the degree of calcium retrieval, represent predictors of complete pain recovery at 1 year after US-PICT.

Furthermore, an UpToDate review on “Calcific tendinopathy of the shoulder” (Prestgaard and Moosmayer, 2021) states that “Barbotage is a US-guided lavage technique that involves breaking up and then aspirating pieces of the calcific deposit.  This approach can be used for chronic and acute, painful cases of calcific tendinopathy.  It is performed on an outpatient basis under local anesthesia, often in combination with a glucocorticoid injection.  This combination of interventions both removes part or all of the calcification and treats the resulting inflammation”.

Pectoralis Nerve Block (PEC 1 and PEC 2) for the Management of Post-Operative Pain Following Mastectomy / Sternotomy for Cardiac Surgery

In a single-case report, Yalamuri et al (2017) stated patients undergoing minimally invasive cardiac surgery have the potential for significant pain from the thoracotomy site.  These investigators reported the successful use of pectoral nerve block types I and II (PECS I and II) as rescue analgesia in a patient undergoing minimally invasive mitral valve repair.  The subject was a 78-year old man, with no history of chronic pain, underwent mitral valve repair via right anterior thoracotomy for severe mitral regurgitation.  After extubation, he complained of 10/10 pain at the incision site that was minimally responsive to intravenous (IV) opioids.  He needed supplemental oxygen because of poor pulmonary mechanics, with shallow breathing and splinting due to pain, and subsequent intensive care unit (ICU) re-admission.  US-guided PECS I and II blocks were carried out on the right side with 30-ml of 0.2 % ropivacaine with 1:400,000 epinephrine.  The blocks resulted in near-complete chest wall analgesia and improved pulmonary mechanics for about 24 hours.  After the single-injection blocks regressed, a 2nd set of blocks was carried out with 266 mg of liposomal bupivacaine mixed with bupivacaine.  This 2nd set of blocks provided extended analgesia for an additional 48 hours.  The patient was weaned rapidly from supplemental oxygen after the blocks because of improved analgesia.  These researchers noted that PECS nerve blocks had been described in the setting of breast surgery to provide chest wall analgesia. They reported the first successful use of PECS nerve blocks to provide effective chest wall analgesia for a patient undergoing minimally invasive cardiac surgery with thoracotomy.  The authors concluded that these blocks may provide an important non-opioid option for the management of pain during recovery from minimally invasive cardiac surgery.

In a prospective RCT, Neethu et al (2018) examined the analgesic efficacy of Us-guided combined pectoral nerve blocks (PECS) I and II in patients scheduled for surgery for breast cancer.  A total of 60 American Society of Anesthesiologists (ASA) status I to II women, aged 18 to 70 years were enrolled in this study.  Patients were randomized into 2 groups (30 patients in each group), PECS (P) group and control (C) group.  In group P, patients received both general anesthesia and US-guided combined PECS I and II.  In group C, patients received only general anesthesia (GA).  These researchers noted pain intensity at rest and during abduction of the ipsilateral upper limb, incidence of post-operative nausea and vomiting (PONV); patient's satisfaction with post-operative analgesia and maximal painless abduction at different time-intervals in both groups.  There was significant decrease in the total amount of fentanyl requirement in the in P group {(140.66 ± 31.80 μg) and (438 ± 71.74 μg)} in comparison to C group {(218.33 ± 23.93 μg) and (609 ± 53.00 μg)} during intra-operative and post-operative period up to 24 hours, respectively.  The time to first analgesic requirement was also more in P group (44.33 ± 17.65 mins) in comparison to C group (10.36 ± 4.97 mins) during post-operative period.  There was less limitation of shoulder movement (pain free mobilization) on the operative site at 4 and 5 hours after surgery in P group in comparison to C group.  However there was no difference in the incidence of PONV (22 out of 30 patients in group P and 20 out of 30 patients in group C) but patients in group P had a better satisfaction score with post-operative analgesia than C group having a p value of < 0.001(Score 1; 5 versus 20; Score 2; 12 versus 9; Score 3; 13 versus 1).  The authors concluded that US-guided combined PECS were an effective modality of analgesia for patients undergoing breast surgeries during peri-operative period.

Versyck et al (2019) noted that surgery is the primary therapeutic intervention for breast cancer and can result in significant post-operative pain.  These investigators searched the current literature and performed a meta-analysis in order to compare the analgesic efficacy of the PECS II block with systemic analgesia alone and with a thoracic paravertebral block for breast cancer surgery.  Primary outcome was post-operative opioid consumption in the first 24 hours after surgery.  Secondary outcomes were pain scores at 0, 3, 6, 9 and 24 hours after surgery, intra-operative opioid consumption, time to first analgesic request and incidence of post-operative nausea and vomiting.  They identified 13 RCTs that included 815 patients.  The Pecs II block significantly reduced post-operative opioid consumption (standardized mean difference [SMD]: -13.64 mg oral morphine equivalents; 95 % confidence interval [CI]: -21.22 to -6.05; p < 0.01) and acute post-operative pain at all intervals in the first 24 hours after surgery compared with systemic analgesia alone.  Compared with the thoracic paravertebral block, the Pecs II block resulted in similar post-operative opioid consumption (SMD: -8.73 mg oral morphine equivalents; 95 % CI: -18.16 to 0.69; p = 0.07) and post-operative pain scores after first measurement.  The authors concluded that the PECSs II block offered improved analgesic efficacy compared with systemic analgesia alone and comparable analgesic efficacy to a thoracic paravertebral block for breast cancer surgery.

Zhao et al (2019) stated that many types of regional nerve blocks have been used during anesthesia for modified radical mastectomy.  In recent years, the use of pectoral nerve (PECS) block has gained importance in post-operative analgesia, but there are still controversies regarding its efficacy.  There is especially no consensus on the optimal type of PECS block to be used.  These researchers evaluated the analgesic efficacy of the PECS block after radical mastectomy.  They searched PubMed, Embase, and the Cochrane library for RCTs for studies regarding PECS versus GA that were published prior to May 31, 2018.  Outcome measures such as intra- and post-operative consumption of opioids, PONV, need for post-operative rescue analgesia, and pain scores were analyzed.  After quality evaluation and data extraction, a meta-analysis was performed using Review Manager 5.3 software, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used for rating the quality of evidence.  A total of 8 RCTs and 2 cohort studies involving 993 patients were eligible.  Compared with the GA group, the PECS block group effectively reduced the intra-operative and post-operative use of opioid drugs, incidence of PONV, need for post-operative rescue analgesia, and pain scores within 0 to 6 hours after surgery.  However, subgroup analysis showed that PECS I block did not have a significant advantage in reducing the intra- and post-operative consumption of opioids.  Results for each outcome indicator were confirmed as having a high or moderate level of evidence.  The authors concluded that even considering the limitations (evaluations of efficacy in different age groups and for chronic pain were not carried out) of this meta-analysis, it can be concluded that the PECS II block is an effective anesthetic regimen in modified radical mastectomy that can effectively reduce the intra- and post-operative consumption of opioids, post-operative PONV, and the need for post-operative rescue analgesia and can alleviate early pain (0 to 6 hours) after surgery.

In a prospective, randomized, single-blinded study, Altıparmak et al (2019) compared the effects of US-guided modified PECS block and erector spinae plane (ESP) block on post-operative opioid consumption, pain scores, and intra-operative fentanyl need of patients undergoing unilateral modified radical mastectomy surgery.  A total of 40 patients (ASA I-II) were allocated to 2 groups.  After exclusion, 38 patients were included in the final analysis (18 patients in the PECS groups and 20 in the ESP group).  Modified pectoral nerve block was performed in the PECS group and erector spinae plane block was performed in the ESP group.  Post-operative tramadol consumption and pain scores were compared between the groups.  Also, intra-operative fentanyl need was measured.  Post-operative tramadol consumption was 132.78 ± 22.44 mg in PECS group and 196 ± 27.03 mg in ESP group (p = 0.001); NRS scores at the 15th and 30th mins were similar between the groups.  However, median NRS scores were significantly lower in PECS group at the post-operative 60th min, 120th min, 12th hour and 24th hour (p = 0.024, p = 0.018, p = 0.021 and p = 0.011, respectively).  Intra-operative fentanyl need was 75 mg in PECS group and 87.5 mg in ESP group.  The difference was not statistically significant (p = 0.263).  The authors concluded that modified PECS block reduced post-operative tramadol consumption and pain scores more effectively than ESP block after radical mastectomy surgery.

Ueshima et al (2019) noted that since the original description in 2011, the array of PECS has evolved.  The PECS block in conjunction with GA can decrease an additional analgesic in peri-operative period for breast cancer surgeries.  Current literature on the PECS block has reported 3 several types (PECS I, PECS II, and serratus plane blocks).  The PECS I block is the same as to the first injection in the PECS II block.  The second injection in the PECS II block and the serratus plane block blocks intercostal nerves (T2 to T6) and provides an analgesic for the breast cancer surgery.  However, the PECS I block (or first injection in the PECS II block) has no analgesic, because both lateral and medial pectralis nerve blocks are motor nerves.  PECS block in previous reports, when added to opioid-based GA, may improve analgesia and decrease narcotic use for breast cancer surgery.  Moreover, PECS block compares favorably with other regional techniques for selected types of surgery.  A major limitation of the PECS block is that it could not block the internal mammary region.  Thus, some studies have reported its ability to block the anterior branches of the intercostal nerve.  The authors concluded that PECS block is an effective analgesic tool for the anterolateral chest; in particular, the PECS block can provide more effective analgesia for breast cancer surgery.

Senapathi et al (2019) stated that combined regional and GA are often used for the management of breast cancer surgery.  Thoracic spinal block, thoracic epidural block, thoracic paravertebral block, and multiple intercostal nerve blocks are the regional anesthesia techniques that have been used in breast surgery, but some anesthesiologists are not comfortable because of the complication and side effects.  In 2012, Blanco et al introduced pectoralis nerve (PECS) II block or modified PECS block as a novel approach to breast surgery.  These researchers determined the effectiveness of combined US-guided PECS II block and GA for reducing intra- and post-operative pain from modified radical mastectomy.  A total of 50 patients undergoing modified radical mastectomy with GA were divided into 2 groups randomly (n = 25), to either PECS (P) group or control (C) group.  Ultrasound-guided PECS II block was done with 0.25 % bupivacaine (P group) or 0.9 % NaCl (C group).  Patient-controlled analgesia (PCA) was used to control post-operative pain.  Intra-operative opioid consumption, post-operative visual analog scale (VAS) score, and post-operative opioid consumption were measured.  Intra-operative opioid consumption was significantly lower in P group (p ≤ 0.05); VAS score at 3, 6, 12, and 24 hours post-operative were significantly lower in P group (p ≤ 0.05); 24 hours post-operative opioid consumption was significantly lower in P group (p ≤ 0.05).  There were no complications following PECS block in both groups, including pneumothorax, vascular puncture, and hematoma.  The authors concluded that combined US-guided PECS II block and GA were effective in reducing pain both intra- and post-operatively in patients undergoing modified radical mastectomy.

Lovett-Carter et al (2019) noted that several studies have evaluated the effect of PECS to improve post-operative analgesia following breast cancer surgery resulting in contradictory findings.  These investigators examined the effect of PECS blocks on post-operative analgesia in women following mastectomies.  They performed a quantitative systematic review in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.  Articles of RCTs that compared PECS block (types I and II) to a control group in patients undergoing mastectomy were included.  The primary outcome was total opioid consumption 24 hours after surgery.  Secondary outcomes included pain scores and side effects.  Meta-analysis was performed using the random effect model.  A total of 7 RCTs with 458 patients were included in the analysis.  The effect of PECS blocks on post-operative opioid consumption compared with control revealed a significant effect, weighted mean difference (WMD) (95 % CI: -4.99 (-7.90 to -2.08) mg intravenous morphine equivalents (p = 0.001).  In addition, post-operative pain compared with control was reduced at 6 hours after surgery: WMD (95 % CI): -0.72 (-1.37 to -0.07), p = 0.03, and at 24 hours after surgery: WMD (95 % CI): -0.91 (-1.81 to -0.02), p = 0.04.  The authors concluded that this quantitative analysis of RCTs demonstrated that the PECS block was effective for reducing post-operative opioid consumption and pain in patients undergoing mastectomy.  The PECS block should be considered as an effective strategy to improve analgesic outcomes in patients undergoing mastectomies for breast cancer treatment.

In a prospective, randomized, single-blind, single-center study, Kaushal et al (2019) compared the relative effectiveness of US-guided serratus anterior plane block (SAPB), pectoral nerves (PECS) II block, and intercostal nerve block (ICNB) for the management of post-thoracotomy pain in pediatric cardiac surgery.  The trial comprised 108 children with congenital heart disease requiring surgery via a thoracotomy.  Subjects were randomly assigned to 1 of the 3 groups: SAPB, PECS II, or ICNB.  All subjects received 3 mg/kg of 0.2 % ropivacaine for US-guided block after induction of anesthesia.  Post-operatively,  IV paracetamol was used for multi-modal and fentanyl was used for rescue analgesia.  A modified objective pain score (MOPS) was evaluated at 1, 2, 4, 6, 8, 10, and 12 hours after extubation.  The early mean MOPS at 1, 2, and 4 hours were similar in the 3 groups.  The late mean MOPS was significantly lower in the SAPB group compared with that of the ICNB group (p < 0.001).  The PECS II group also had a lower MOPS compared with the ICNB group at 6, 8, and 10 hours (p < 0.001), but the MOPS was comparable at hour 12 (p = 0.301).  The requirement for rescue fentanyl was significantly higher in ICNB group in contrast to the SAPB and PECS II groups.  The authors concluded that SAPB and PECS II fascial plane blocks were equally effective in post-thoracotomy pain management compared with ICNB; moreover, they had the additional benefit of being longer lasting and were as easily carried out as the traditional ICNB.

Gaweda et al (2020) stated that effective post-operative pain control remains a challenge for patients undergoing cardiac surgery.  Novel regional blocks may improve pain management for such patients and can shorten their hospital LOS.  In a prospective, double-blinded RCT, these researchers compared post-operative pain intensity in patients undergoing cardiac surgery with either erector spinae plane (ESP) block or combined ESP and pectoralis nerve (PECS) blocks.  This trial included 30 patients undergoing mitral/tricuspid valve repair via mini-thoracotomy.  Patients were randomly allocated to one of two groups: ESP or PECS + ESP group (1:1 randomization).  Patients in both groups received a single-shot, US-guided ESP block.  Subjects in PECS + ESP group received additional PECS blocks.  Each patient had to be extubated within 2 hours from the end of the surgery.  Pain was treated via a patient-controlled analgesia (PCA) pump.  The primary outcome was the total oxycodone consumption via PCA during the 1st post-operative day.  The secondary outcomes included pain intensity measured on the VAS, patient satisfaction, Prince Henry Hospital Pain Score (PHHPS), and spirometry.  Patients in the PECS + ESP group used significantly less oxycodone than those in the ESP group: median 12 [IQR: 6 to 16] mg versus 20 [IQR: 18 to 29] mg (p = 0.0004).  Moreover, pain intensity was significantly lower in the PECS + ESP group at each of the 5 measurements during the 1st post-operative day.  Patients in the PECS + ESP group were more satisfied with pain management.  No difference was observed between both groups in PHHPS and spirometry.  The authors concluded that the addition of PECS blocks to ESP reduced consumption of oxycodone via PCA, reduced pain intensity on the VAS, and increased patient satisfaction with pain management in patients undergoing mitral/tricuspid valve repair via mini-thoracotomy.

Piriformis Muscle Injection

In a cadaveric study, Finnoff et al (2008) compared the accuracy of ultrasound (US)-guided piriformis injections with fluoroscopically guided contrast-controlled piriformis injections.  A total of 20 piriformis muscles in 10 un-embalmed cadavers were injected with liquid latex using both fluoroscopically guided contrast-controlled and US-guided injection techniques.  All injections were performed by the same experienced individual.  Two different colors of liquid latex were used to differentiate injection placement for each procedure, and the injection order was randomized.  The gluteal regions were subsequently dissected by an individual blinded to the injection technique.  Colored latex observed within the piriformis muscle, sheath, or both was considered an accurate injection.  A total of 19 of 20 US-guided injections (95 %) correctly placed the liquid latex within the piriformis muscle, whereas only 6 of the 20 fluoroscopically guided contrast-controlled injections (30 %) were accurate (p = 0.001).  The liquid latex in 13 of the 14 missed fluoroscopically guided contrast-controlled piriformis injections and the single missed US-guided injection was found within the gluteus maximus muscle.  In the single remaining missed fluoroscopically guided contrast-controlled piriformis injection, the liquid latex was found within the sciatic nerve.  The authors concluded that in this cadaveric model, US-guided piriformis injections were significantly more accurate than fluoroscopically guided contrast-controlled injections.  Despite the use of bony landmarks and contrast, most of the fluoroscopically attempted piriformis injections were placed superficially within the gluteus maximus.  Clinicians performing piriformis injections should be aware of the potential pitfalls of fluoroscopically guided contrast-controlled piriformis injections and consider using US guidance to ensure correct needle placement.

The authors stated that this study had several drawbacks.  First, a single investigator performed all injections.  The investigator was pain medicine fellowship-trained, was board-certified in pain medicine, and had extensive procedural experience with both fluoroscopically guided and US‐guided procedures.  In consideration of the relatively poor accuracy of the fluoroscopically guided piriformis injection, it was worth noting that he had several years' more experience with the fluoroscopic than with the US technique.  Nonetheless, the results of this investigation may not be applicable to other clinicians with different training and experiential backgrounds.  Second, this investigation used un-embalmed cadavers rather than live participants.  The study necessitated 2 injections in each piriformis muscle and "surgical" confirmation of injectate placement via dissection, a design that could not be completed in live individuals.  These researchers did not think that the use of cadavers appreciably affected their findings.  Their contrast patterns were similar to those observed in live individuals, so it was unlikely that the cadaver model biased the results against fluoroscopy.  On the contrary, the inability to take full advantage of the dynamic soft tissue imaging capabilities of US may have negatively biased the accuracy of the US technique.  For example, the inferior gluteal artery as imaged via Doppler techniques may be used in live persons as a reference mark for the inferior border of the piriformis muscle as well as the location of the sciatic nerve.  These investigators thought that the results of this study appeared to be transferable to the clinical setting.

Blunk et al (2013) noted that patients presenting with buttock pain syndromes are common.  Up to 8 % of these conditions may be attributed to piriformis syndrome.  Included in several therapeutic and diagnostic approaches, injections directly into the piriformis muscle may be performed.  Because the muscle lies very close to neurovascular structures, electromyographic (EMG), fluoroscopic, computed tomographic (CT), and magnetic resonance imaging (MRI) guidance have been employed.  In few studies, an US-guided technique was used to inject a local anesthetic into the piriformis muscle without impairing adjacent neuronal structures.  In a feasibility study in healthy human subjects, These researchers confirmed US-guided injections by MRI.  In 10 male human subjects, US-guided injections of 3 ml of a local anesthetic into the piriformis muscle were performed.  Directly after the injection, the subjects were placed in an MRI scanner, and the placement of the liquid depot was confirmed by MRI imaging.  Somatosensory deficits were evaluated after the injection.  The MRI showed that 9 of 10 of the injections were correctly placed within the piriformis muscle.  The distance of the depot to the sciatic nerve decreased over time due to dispersion, but the nerve itself was not reached in the MRI.  Only 1 subject experienced slight, short-term sensorimotor deficits.  The authors concluded that MRI confirmed the correct placement of the local anesthetic within the muscle.  The dispersion of the fluid 30 mins after the injection could be visualized.  Moreover, only 1 subject experienced slight motor deficits without anatomical correlate.  These researchers stated that this US-guided method will be further employed in ongoing clinical studies.

Fabregat et al (2014) noted that approximately 6 % to 8 % of lumbar pain cases, whether associated with radicular pain or not, may be attributed to the presence of piriformis muscle syndrome.  Available treatments, among others, include pharmacotherapy, physical therapy, and injections of different substances into the muscle.  Various methods have been used to confirm correct needle placement during these procedures, including EMG, fluoroscopy, CT, or MRI.  Ultrasonography has now become a widely used technique and therefore may be an attractive alternative for needle guidance when injecting this muscle.  In a feasibility study, these researchers examined the reliability of US in piriformis injection of patients with piriformis syndrome.  A tot of 10 patients with piriformis muscle syndrome were injected with botulinum toxin A (BTX-A) using a US-guided procedure.  Then patients were administered 2 ml iodinated contrast and were then transferred to the CT scanner, where they underwent pelvic and hip imaging to assess intra-muscular (IM) distribution of the iodinated contrast.  Of all 10 study patients (8 women, 2 men), 9 had IM or intra-fascial contrast distribution.  Distribution did not go deeper than the piriformis muscle in any of the patients.  The absence of contrast (intravascular injection) was not observed in any case.  The authors concluded that US-guided puncture may be a reliable and simple procedure for injection of the piriformis muscle, as long as good education and training are provided to the operator.  These researchers stated that US has a number of advantages over traditional approaches, including accessibility and especially no ionizing radiation exposure for both health care providers and patients.  Moreover, they noted that published data regarding US-guided treatments were still very limited; and further studies should focus on outcome and safety of US-guided pain interventions compared to traditional imaging techniques such as fluoroscopy.

Fowler et al (2014) stated that piriformis muscle injections are most often performed using fluoroscopic guidance; however, US guidance has recently been described extensively in the literature.  No direct comparisons between the 2 techniques have been performed.  In a randomized, comparative trial, these researchers compared the efficacy and efficiency of fluoroscopic- and US-guided techniques.  A total of 28 patients with a diagnosis of piriformis syndrome, based on history and physical examination, who had failed conservative treatment were enrolled in the study.  Patients were randomized to receive the injection either via US or fluoroscopy.  Injections consisted of 10 ml of 1 % lidocaine with 80 mg of triamcinolone.  The primary outcome measure was numeric pain score (NPS), and secondary outcome measures included functional status as measured by the Multidimensional Pain Inventory, patient satisfaction as measured by the Patient Global Impression of Change scale, and procedure timing characteristics.  Outcome data were measured pre-procedure, immediately post-procedure, and 1 to 2 weeks and 3 months post-procedure.  These investigators found no statistically significant differences in NPS, patient satisfaction, procedure timing characteristics, or most functional outcomes when comparing the 2 techniques.  Statistically significant differences between the 2 techniques were found with respect to the outcome measures of household chores and outdoor work.  The authors concluded that US-guided piriformis injections provided similar outcomes to fluoroscopically guided injections without differences in imaging, needling, or overall procedural times.

Misirlioglu et al (2015) stated that piriformis syndrome (PS), which is characterized by pain radiating to the gluteal region and posterior leg, is accepted as one of the causes of sciatalgia.  Although the importance of local piriformis muscle injections whenever PS is clinically suspected has been shown in many studies, there are not enough studies considering the clinical efficacy of these injections.  In a prospective, double-blinded, randomized controlled trial (RCT), these investigators examined the differences between local anesthetic (LA) and LA + corticosteroid (CS) injections in the treatment of PS.  A total of 57 patients having unilateral hip and/or leg pain with positive FAIR test and tenderness and/or trigger point at the piriformis muscle were evaluated.  Out of 50 patients randomly assigned to 2 groups, 47 patients whose pain resolved at least 50 % from the baseline after the injection were diagnosed as having PS.  The first group (n = 22) received 5 ml of lidocaine 2 % while the second group (n = 25) received 4 ml of lidocaine 2 % + 1 ml of betamethasone under US-guidance.  Outcome measures included numeric rating scale (NRS) and Likert analogue scale (LAS).  No statistically significant difference (p > 0.05) was detected between the groups in NRS score values at resting (p = 0.814), night (p = 0.830), and in motion (p = 0.145), and LAS values with long duration of sitting (p = 0.547), standing (p = 0.898), and lying (p = 0.326) with evaluations at baseline, first week, and first and third months after the injection.  A statistically highly significant (p < 0.005) reduction of pain was evaluated through NRS scores at resting (p = 0.001), in motion (p = 0.001), and at night (p = 0.001) and LAS values with long duration of sitting (p = 0.001), standing (p = 0.001), and lying (p = 0.001) in both of the groups.  The authors concluded that LA injections for the PS were found to be clinically effective.  However, addition of CS to LA did not give an additional benefit. 

Payne (2016) described the techniques for performing US-guided procedures in the hip region, including intra-articular hip injection, iliopsoas bursa injection, greater trochanter bursa injection, ischial bursa injection, and piriformis muscle injection.  The author stated that US is commonly used to evaluate hip region pathologic conditions and to guide interventions in the hip region for diagnostic and therapeutic purposes; US confers many advantages compared with other commonly used imaging modalities, including real-time visualization of muscles, tendons, bursae, neurovascular structures, and the needle during an intervention.  The author stated that US-guided injection techniques have been described for many commonly performed procedures in the hip region, and many studies have been performed demonstrating the safety and accuracy of these techniques.

In a prospective study, Terlemez and Ercalık (2019) examined the effect of a piriformis injection on neuropathic pain in patients with PS.  A total of 30 patients with unilateral hip and/or leg pain, a positive FAIR test (increased H-reflex latency with Flexion, Adduction and Internal Rotation), and a trigger point at the piriformis muscle were enrolled in this study.  All of the patients exhibited neuropathic pain scored according to the Douleur Neuropathique 4 (DN4) of greater than or equal to 4 for at least 6 months.  All of the patients received 4 ml of lidocaine 2 % + 1 ml of betamethasone to the piriformis muscle under US-guidance.  The NRS, DN4, and the painDETECT (PD) questionnaire were used for outcome assessment.  A statistically significant improvement was observed in all scores (p < 0.001) when both first week and first month results were compared with the baseline values.  Comparison of the first week results with those of the first month revealed a statistically significant improvement in only the NRS and PD scores (p < 0.001).  The greatest improvement in all scores was observed in the first week after the injection.  A mild increase was observed in all scores at the first month compared to the first week.  The authors concluded that a piriformis injection was found to be effective for both somatic and neuropathic pain in PS patients.

Furthermore, an UpToDate review on "Approach to hip and groin pain in the athlete and active adult" (Johnson, 2020) states that "Treatment begins with physical therapy involving strengthening of the pelvic and hip region and stretching of the piriformis.  Appropriate analgesics for neuropathic pain are taken as needed.  Physical therapy is effective in the majority of cases.  Ultrasound-guided glucocorticoid injections have been beneficial in some cases, and botulinum toxin injections have also been used.  Surgery (typically a piriformis tenotomy) may be considered if symptoms are debilitating and persist despite conservative therapy".

Popliteal Nerve Block

Sinha and Chan (2004) stated that US is a novel method of nerve localization but its use for lower extremity blocks appeared limited with only reports for femoral 3-in-1 blocks.  These investigators reported a case series of popliteal sciatic nerve blocks using US guidance to illustrate the clinical usefulness of this technology.  The sciatic nerve was localized in the popliteal fossa by US imaging in 10 patients using a 4- to 7-MHz probe and the Philips ATL HDI 5,000 unit.  Ultrasound imaging showed the sciatic nerve anatomy, the point at which it divides, and the spatial relationship between the peroneal and tibial nerves distally.  Needle contact with the nerve(s) was further confirmed with nerve stimulation.  Circumferential local anesthetic spread within the fascial sheath after injection appeared to correlate with rapid onset and completeness of sciatic nerve block.  The authors concluded that their preliminary experience suggested that US localization of the sciatic nerve in the popliteal fossa was a simple and reliable procedure.  It helped guide block needle placement and assessed local anesthetic spread pattern at the time of injection.

Perlas et al (2008) noted that real time US guidance is a recent development in the area of peripheral nerve blockade.  There are limited data from prospective randomized trials comparing its efficacy to that of traditional nerve localization techniques.  In the present study, these researchers tested the hypothesis that US guidance improved the success rate of sciatic nerve block at the popliteal fossa when compared with a nerve stimulator-guided technique.  After Institutional Research Ethics Board approval and informed consent, a total of 74 patients undergoing elective major foot or ankle surgery were randomly assigned to receive a sciatic nerve block at the popliteal fossa guided by either US (group US, transverse view, needle in plane approach above the sciatic nerve bifurcation), or nerve stimulation (group NS, single injection, 10 cm proximal to the knee crease).  A standardized local anesthetic admixture (15 ml of 2 % lidocaine with 1:200,000 epinephrine and 15 ml of 0.5 % bupivacaine) was used.  Sensory and motor function was assessed by a blinded observer at pre-determined intervals for up to 1 hour.  Block success was defined as a loss of sensation to pinprick within 30 mins in the distribution of both tibial and common peroneal nerves.  Group US had a significantly higher block success rate than group NS (89.2 % versus 60.6 %, p = 0.005), while the procedure time was similar.  The authors concluded that US guidance enhanced the quality of popliteal sciatic nerve block compared with single injection, nerve stimulator-guided block using either a tibial or peroneal endpoint; US guidance resulted in higher success, faster onset, and progression of sensorimotor block, without an increase in block procedure time, or complications.

van Geffen et al (2009) stated that the direct visualization of nerves and adjacent anatomical structures may make US the preferred method for nerve localization.  In a prospective, randomized study, these investigators examined if, for distal sciatic nerve block in the popliteal fossa, an US-guided technique would result in the use of less local anesthetic without changing block characteristics and quality.  Using electrical nerve stimulation or US guidance, the nerve was identified in 2 groups of 20 patients scheduled for lower limb surgery.  Hereafter lignocaine 1.5 % with adrenaline 5 microg/ml was injected.  The attending anesthesiologist assessed the injected volume.  Significantly less local anesthetic was injected in the US group compared to the nerve stimulation group (17 versus 37 ml, p < 0.001), while the overall success rate was increased (100 % versus 75 %; p = 0.017).  The authors concluded that the use of US localization for distal sciatic nerve block in the popliteal fossa reduced the required dose of local anesthetic significantly, and was associated with a higher success rate compared to nerve stimulation without changing block characteristics.

Bendtsen et al (2011) tested the hypothesis that US-guided catheter placement improved the success rate of continuous sciatic nerve sensory blockade compared with catheter placement with nerve stimulation guidance.  After research ethics committee approval and informed consent, a total of 100 patients scheduled for elective major foot and ankle surgery were randomly allocated to popliteal catheter placement either with US or nerve stimulation guidance.  The primary outcome was the success rate of sensory block the first 48 post-operative hours.  Successful sensory blockade was defined as sensory loss in both the tibial and common peroneal nerve territories at 1, 6, 24, and 48 hours post-operatively.  The US group had significantly higher success rate of sensory block compared with the nerve stimulation group (94 % versus 79 %, p = 0.03).  US compared with nerve stimulation guidance also entailed reduced morphine consumption (median of 18 mg [range of 0 to 159 mg] versus 34 mg [range of 0 to 152 mg], respectively, p = 0.02), fewer needle passes (median of 1 [range of 1 to 6] versus 2 [range of 1 to 10], respectively, p = 0.0005), and greater patient satisfaction (median numeric rating scale 9 [range of 5 to 10] versus 8 [range of 3 to 10)] respectively, p = 0.0006) during catheter placement.  The authors concluded that US guidance used for sciatic catheter placement improved the success rate of sensory block, number of needle passes, patient satisfaction during catheter placement, and morphine consumption compared with nerve stimulation guidance.

In a prospective, randomized study, Cataldo et al (2012) compared the success rate and performance time of popliteal block during resident's training for regional anesthesia by using nerve stimulation (NS) or combined nerve stimulation and US (NS + US).  A total of 70 adult patients undergoing hallux valgus surgery were randomly assigned to receive sciatic nerve block at popliteal fossa with US+NS or NS alone with a double injection technique for peroneal and tibial branches, respectively.  Two residents experienced with nerve stimulator performed the procedures after a learning phase concerning US.  A local anesthetic solution, containing 10 ml of 0.75 % ropivacaine and 10 ml of 2 % lidocaine was used: 12 ml were infiltrated close the tibial nerve, and 8ml were infiltrated close the common peroneal nerve.  Block success rate, sensory block onset time, block performance time were evaluated.  Recourse to general anesthesia was considered as failure.  No differences were detected in success rate and onset time of sensory block between the 2 groups (p > 0.05).  The time to block tibial nerve and the overall block time were significantly faster in US+NS group (p < 0.05).  The authors concluded that US guidance for popliteal nerve block resulted in similar success rate with a faster procedure time when compared with nerve stimulator, thus providing a possible effect on resident education and operating room efficiency.

In a randomized, single-blinded, clinical trial, Lam et al (2014) compared procedural times and related outcomes for US- versus nerve stimulation-guided lateral popliteal-sciatic nerve blockade specifically in obese patients.  With Institutional Review Board approval and informed consent, patients with a body mass index (BMI) greater than 30 kg/m(2) who were scheduled for foot/ankle surgery and desiring a peripheral nerve block were offered enrollment.  Study patients were randomly assigned to receive a lateral popliteal-sciatic nerve block under either US or nerve stimulation guidance.  The patient and assessor were blinded to group assignment.  The primary outcome was procedural time in seconds.  Secondary outcomes included number of needle re-directions, procedure-related pain, patient satisfaction with the block, success rate, sensory and motor onset times, block duration, and complication rates.  A total of 24 patients were enrolled and completed the study.  All patients had successful nerve blocks. The mean procedural times (SD) were 577 (57) seconds under nerve stimulation and 206 (40) seconds with US guidance (p <0 .001; 95 % CI: 329 to 412 seconds).  Patients in the US group had fewer needle re-directions and less procedure-related pain, required less opioids, and were more satisfied with their block procedures.  There were no statistically significant differences in other outcomes.  The authors concluded that the findings of this study showed that, for obese patients undergoing lateral popliteal-sciatic nerve blocks, US guidance reduced the procedural time and procedure-related pain and increased patient satisfaction compared to nerve stimulation while providing similar block characteristics.

In a prospective, randomized study, Karaarslan et al (2016) compared the efficacy, post-operative pain scores, adverse effects, additional analgesic requirements, and patient satisfaction scores of US-guided sciatic nerve block by popliteal approach with spinal anesthesia for hallux valgus correction surgery.  A total of 60 patients scheduled for hallux valgus correction surgery were enrolled in this trial.  Unilateral spinal block was performed on patients in the spinal anesthesia group.  Popliteal block group patients received popliteal sciatic nerve block with guidance by both nerve stimulator and US.  Durations of anesthetic and operative interventions and time until the initiation of surgery were recorded for both groups.  Pain magnitude of the patients at the second, fourth, sixth, 12th, and 24th hours following anesthetic interventions were assessed with a visual analog scale (VAS).  Adverse effects such as post-operative urinary retention and post-dural puncture headache were recorded.  Also, patient satisfaction was recorded.  Patients were interviewed by phone for anesthetic and operative complications at 72 hours post-operatively.  Spinal anesthesia group patients exhibited hypotension, bradycardia, post-dural puncture headache, and urinary retention rates of 6.6 %, 3.3 %, 10 %, and 3.3 %, respectively.  Popliteal block group patients showed none of these adverse effects.  Moreover, VAS scores of the patients at the second, fourth, sixth, and 12th hours were significantly lower (p < 0.001, p = 0.003, p < 0.001, p < 0.001, respectively), post-operative first analgesic requirement times were significantly longer (p < 0.001), and pain satisfaction scores were significantly higher (p < 0.001) in the popliteal block group.  The authors concluded that given the complications related to spinal anesthesia and its insufficiency to maintain analgesia postoperatively, they believed the preferred anesthetic method should be peripheral nerve blocks for hallux valgus correction surgeries.  Level of Evidence = I.

Quadratus Lumborum Nerve Block for Post-Operative Pain Control After Abdominal Surgery

In a prospective RCT, Ishio et al (2017) determined the efficacy of US-guided posterior quadratus lumborum block (QLB) in treating post-operative pain following laparoscopic gynecologic surgery.  A total of 70 adult patients scheduled for elective laparoscopic gynecological surgery under general anesthesia were enrolled in this trial.  Patients were randomly assigned to either the QLB group or control group.  In the QLB group, patients underwent posterior QLB with 20 ml of 0.375 % ropivacaine on each side.  Patients were blinded to treatment.  At 0, 1, 3, and 24 hours after anesthesia recovery, evaluator recorded the severity of post-operative pain in movement and at rest using a Numeric Rating Scale (NRS).  These researchers also evaluated the severity of nausea using NRS and number of additional analgesics.  Immediately after recovery from anesthesia, the NRS score for pain in movement did not differ significantly between groups; NRS scores for pain both in movement and at rest were significantly higher in the control group than in the QLB group at 1, 3, and 24 hours after recovery from anesthesia.  The authors concluded that these findings suggested that posterior QLB significantly reduced post-operative pain in movement and at rest following laparoscopic gynecologic surgery.

Hussein (2018) stated that QLB has 4 approaches.  However, there is difference between the 4 approaches regarding efficacy, safety and adverse effects.  This investigator compared the analgesic effect between trans-muscular and intra-muscular approaches of the QLB in pediatric patients for elective lower abdominal surgery.  A total of 54 patients aged 1 to 6 years were enrolled; patients of both genders were selected.  Subjects were randomly classified into 2 groups: Group TQL included patients (n = 27) in whom bilateral QLB was performed using trans-muscular approach, and Group IQL included patients (n = 27) who underwent bilateral QLB using an intra-muscular approach.  The primary outcome measure was the number of patients who required rescue analgesia in the first 24 hours.  The secondary outcome measures were Face, Legs, Arms, Cry, Consolability (FLACC) score, heart rate, non-invasive blood pressure at 2, 4, 6, 12, and 24 hours post-operatively, and post-operative complications (e.g., local hematoma, quadriceps muscle weakness,).  In the first 24 hours after surgery, 13 patients in the IQL group (48.1 %) required rescue analgesia, whereas only 5 patients in the TQL group (18.5 %) required rescue analgesia.  The FLACC score was lower in the TQL group than the IQL group at all time intervals up to 24 hours post-operatively.  In the TQL group, 8 patients (29.6 %) developed quadriceps weakness; whereas, only 1 patient (3.7 %) in the IQL group developed quadriceps weakness.  The author concluded that TQL was better than IQL in the analgesic efficacy following the pediatric lower laparotomy.

Zhu et al (2019) stated that QLB is increasingly being used as a new abdominal nerve block technique.  In some studies of mid and lower abdominal and hip analgesia, continuous QLB achieved favorable outcomes as an alternative to continuous intravenous analgesia with opioids.  However, the use of continuous QLB for upper abdominal pain is less well characterized.  In an open-label RCT, these investigators examined the effects of continuous anterior QLB (CQLB) on post-operative pain and recovery in patients undergoing open liver resection.  A total of 63 patients underwent elective open liver resection were randomly divided into CQLB group (n = 32) and patient-controlled analgesia (PCA) group  (n = 31).  Patients in CQLB group underwent US-guided anterior QLB at the second lumbar vertebral transverse processes before general anesthesia, followed by post-operative CQLB analgesia.  Patients in PCA group underwent continuous intravenous analgesia post-operatively.  Post-operative NRS pain scores upon coughing and at rest, self-administered analgesic counts, rate of rescue analgesic use, time to first out-of-bed activity and anal flatus after surgery, and incidences of analgesic-related adverse effects were recorded.  Post-operative NRS pain scores on coughing in CQLB group at different time-points and NRS pain score at 48 hours after surgery were significantly lower than those in PCA group (p < 0.05).  Time to first out-of-bed activity and anal flatus after surgery in CQLB group were significantly earlier than those in PCA group (p < 0.05).  No significant differences of post-operative self-administered analgesic counts, rate of post-operative rescue analgesic usage, or incidences of analgesic-related adverse effects were found between the 2 groups (p > 0.05).  The authors concluded that US-guided anterior QLB significantly alleviated the pain during coughing after surgery, shortened the time to first out-of-bed activity and anal flatus, promoting post-operative recovery of the patients undergoing open liver resection.

Salama (2020) stated that adequate pain control after cesarean section (CS) is important to help the newly delivered mothers to feed and care their newborns together with early ambulation of the parturients to avoid the risk of thrombo-embolism and development of chronic abdominal and pelvic pain.  In a RCT, these investigators compared the efficacy of QLB and intra-thecal morphine for post-operative analgesia after CS.  A total of 90 pregnant women with a gestation of 37 weeks or more scheduled for elective CS were enrolled in this study.  All subjects received spinal anesthesia, and after surgery, QLB was performed.  They were randomly allocated to control group (CG, 0.1-ml saline added to spinal drug and 24-ml saline for QLB), intra-thecal morphine group (ITM, 0.1-mg morphine added to spinal drug and 24-ml saline for QLB), or QLB group (0.1-ml saline added to spinal drug and 24-ml 0.375 % ropivacaine for QLB).  Integrated Analgesia Score (IAS), NRS at rest and during movement, morphine requirements in the first 48 hours, time to first morphine dose, time to first ambulation, and morphine related side effects were recorded.  IAS and NRS scores at rest and during movements were significantly less in QLB and ITM than CG.  Moreover, QLB had lower IAS and NRS scores at rest and during movements in comparison to ITM.  Time to first morphine dose was significantly longer in QLB than in ITM and CG.  Also, morphine requirements in the first 48 hours was significantly lower in QLB than ITM and CG (18.2 ± 9.6 mg in QLB versus and 42.8 ± 10.4 mg and 61 ± 12.9 mg in ITM and CG, respectively) (p = 0.001).  No significant difference between the 3 groups regarding time to first ambulation (13.4 ± 1.8 hours in QLB versus 11.7 ± 1.9 hours in CG and 12.9 ± 1.6 hours in ITM).  Incidence of morphine related side effects was significantly higher in ITM compared to CG and QLB.  The authors concluded that QLB and intra-thecal morphine were effective analgesic regimens after CS.  However, QLB provided better long lasting analgesia together with reduction of total post-operative morphine consumption.

Sato (2019) noted that US-guided QLB is a regional anesthetic technique that can provide peri-operative analgesia for all age groups, including pediatric patients undergoing abdominal surgery.  This researcher hypothesized that the QLB would be as effective as a caudal block, the gold standard of pediatric lower abdominal regional anesthesia, in providing pain control after ureteral re-implantation but also have a longer duration.  A total of 47  pediatric patients aged f 1 to 17 years undergoing bilateral ureteral re-implantation surgery via a low transverse incision were enrolled and randomized into the QLB and caudal block groups.  All blocks were performed pre-operatively under general anesthesia. This investigator analyzed the following outcomes: the requirement for narcotic analgesics, pain score, episodes of emesis, and complications at 0, 4, 24, and 48 hours post-operatively.  The study included 44 patients after excluding 3 who were ineligible.  The fentanyl requirement for post-operative rescue analgesia during the first 24 hours was significantly lower in the QLB group than in the caudal block group (median [interquartile range (IQR)]: 0 [0 to 1] versus 3 [0 to 5], p = 0.016, 95 % confidence intervals (CI): -4 to 0); but not at 30 mins, 4 hours or 48 hours.  No significant difference was observed in the pain scores or the incidence of interventions to treat nausea and vomiting during the entire period.  No post-operative complication was observed.  The author concluded that QLB was more effective in reducing the post-operative opioid requirement for rescue analgesia during the initial 24 hours than caudal ropivacaine/morphine.

Saphenous Nerve Block for Post-Operative Pain Control After Open Reduction and Internal Fixation of Trimalleolar Fracture

Manickam et al (2009) noted that saphenous nerve (SN) block can be technically challenging because it is a small and exclusively sensory nerve.  Traditional techniques using surface landmarks and nerve stimulation are limited by inconsistent success rates.  This descriptive prospective study examined the feasibility of performing an US-guided SN block in the distal thigh.  After the research ethics board's approval and written informed consent, 20 patients undergoing ankle or foot surgery underwent US of the medial aspect of the thigh to identify the SN in the adductor canal, as it lies adjacent to the femoral artery (FA), deep to the sartorius muscle.  An insulated needle was advanced in plane under real-time guidance toward the nerve.  After attempting to elicit paresthesia with nerve stimulation, 2 % lidocaine with 1:200,000 epinephrine (5 ml) and 0.5 % bupivacaine (5 ml) were injected around the SN.  The SN was identified in all patients, most frequently in an antero-medial position relative to the FA, at a depth of 2.7 +/- 0.6 cm and 12.7 +/- 2.2 cm proximal to the knee joint.  Complete anesthesia in the SN distribution developed in all patients by 25 mins after injection.  The authors concluded that in this small descriptive study, US-guided SN block in the adductor canal was technically simple and reliable, providing consistent nerve identification and block success.  This appeared to be a small feasibility study.

Fredrickson et al (2011) stated that US guidance reduces the required local anesthetic volume for successful peripheral nerve blockade, but it is unclear whether this impacts post-operative analgesia.  In a prospective, randomized, observer-blinded study, these researchers hypothesized that a low-volume US-guided ankle block would provide similar analgesia after foot surgery compared with a conventional-volume surface landmark technique.  A total of 72 patients presenting for elective foot surgery under general anesthesia were randomized to receive a low-volume US-guided ankle block (n = 37; ropivacaine 0.5 % adjacent the anterior/posterior tibial arteries and short saphenous vein; subcutaneous infiltration around the saphenous and superficial peroneal nerves) or conventional-volume surface landmark guided technique (n = 35; 30-ml of ropivacaine 0.5 %).  Patients received regular post-operative acetaminophen, diclofenac, and rescue tramadol.  Assessment was in the recovery room and at 24 hours for pain and tramadol consumption.  Mean (SD) total local anesthetic volume for the low-volume US group was 16 (2.1) ml.  Block success in the recovery room was similar between groups (low-volume US 89 % versus conventional-volume landmark 80 %, p = 0.34; however, during the first 24 hours, numerically rated (0 to 10) "average pain" (median [10 to 90th percentiles] = 1 [0 to 4] versus 0 [0 to 2], p = 0.01), worst pain at rest (1 [0 to 6] versus 0 [0 to 2], p = 0.03), and the proportion of patients requiring rescue tramadol (% [95 % confidence interval (CI)]: 50 [34 to 46] versus 20 [10 to 36], p = 0.01) were higher in the low-volume US group.  Numerically rated numbness, weakness, satisfaction, and procedural time were similar between groups.  The authors concluded that low-volume US-guided ankle block was associated with a high block success rate after foot surgery; however, compared with a conventional volume (surface landmark) technique, the reduced local anesthetic volume marginally compromised post-operative analgesia during the first 24 hours.

Peterson et al (2020) noted that peri-articular injection or anesthesiologist-performed adductor canal block are commonly used for pain management after total knee arthroplasty (TKA).  A surgeon-performed, intra-articular saphenous nerve block has been recently described.  There is insufficient data comparing the efficacy and safety of these methods.  In a retrospective, 2-surgeon cohort study, these researchers compared short-term peri-operative outcomes after primary TKA in 50 consecutive patients with surgeon-performed high-dose peri-articular injection and intra-articular saphenous nerve block (60-ml 0.5 % bupivacaine, 30-ml saline, 30-mg ketorolac) and 50 consecutive patients with anesthesiologist-performed adductor canal catheter (0.25 % bupivacaine 6 ml/hour infusion pump placed post-operatively with US guidance).  Chart review assessed pain scores through POD #1, opioid use, length of stay (LOS), and short-term complications, including local anesthetic systemic toxicity.  Statistical analysis was performed with 2-tailed Student's t-test.  The high-dose peri-articular injection cohort had significantly lower pain scores in the post-anesthesia care unit (mean difference [MD] 1.4, p = 0.035), on arrival to the in-patient ward (MD 1.7, p = 0.013), and required less IV narcotics on the day of surgery (MD 6.5 MME, p = 0.0004).  There was no significant difference in pain scores on POD #1, total opioid use, day of discharge, or short-term complications.  There were no adverse events (AEs) related to the high-dose of bupivacaine.  The authors concluded that compared with post-operative adductor canal block catheter, an intra-operative high-dose peri-articular block demonstrated lower pain scores and less IV narcotic use on the day of surgery.  No difference was noted in pain scores on POD #1, time to discharge, or complications.  There were no cardiovascular complications (local anesthetic systemic toxicity) despite the high-dose of bupivacaine injected.  Level of Evidence = III.  The US guidance in this study was provided to the adductor canal block group; not to the intra-articular saphenous nerve block group.

Scapular Thoracic Bursitis Injection

Osias et al (2018) noted that symptomatic scapulothoracic disorders, including scapulothoracic crepitus and scapulothoracic bursitis are uncommon disorders involving the scapulothoracic articulation that have the potential to cause significant patient morbidity.  Scapulothoracic crepitus is the presence of a grinding or popping sound with movement of the scapula that may or may not be symptomatic, while scapulothoracic bursitis refers to inflammation of bursa within the scapulothoracic articulation.  Both entities may occur either concomitantly or independently.  Nonetheless, the constellation of symptoms manifested by both entities has been referred to as the snapping scapula syndrome.  Various causes of scapulothoracic crepitus include bursitis, variable scapular morphology, post-surgical or post-traumatic changes, osseous and soft tissue masses, scapular dyskinesis, and postural defects.  Imaging is an important adjunct to the physical examination for accurate diagnosis and appropriate treatment management.  Non-operative management such as physical therapy and local injection can be effective for symptoms secondary to scapular dyskinesis or benign, non-osseous lesions.  Surgical treatment is utilized for osseous lesions, or if non-operative management for bursitis has failed.  Open, arthroscopic, or combined methods have been performed with good clinical outcomes.

Walter et al (2019) stated scapulothoracic pain is a common ailment, but the underlying cause can be difficult to diagnose in a timely manner, and treatment options are limited.  These researchers retrospectively reviewed their experience using US-guided therapeutic scapulothoracic interval steroid injections to treat scapulothoracic pain and reviewed correlative MRI findings over a 5-year period.  Although a variety of structural causes are known to cause scapulothoracic pain, in the authors’ experience, most cases lacked correlative imaging findings.  The authors concluded that US-guided scapulothoracic interval injections provided a safe, easily performed diagnostic and therapeutic tool for treating patients with periscapular pain, providing at least short-term symptom relief.

Sciatic Nerve Block

An UpToDate review on "Lower extremity nerve blocks: Techniques" (Jeng and Rosenblatt, 2019a) states that "The sciatic nerve block provides complete anesthesia of the leg below the knee, with the exception of a strip of medial skin innervated by the saphenous nerve.  Combined with femoral or saphenous nerve block, it provides analgesia for surgery of the distal anterior thigh; anterior knee; and lateral calf, ankle, or foot.  The sciatic nerve block can be performed using either an anterior or a posterior approach, with similar success rates for surgery below the knee … Ultrasound-guided sciatic block – For an ultrasound-guided sciatic block, the ultrasound transducer is held transverse to the course of the nerve.  The sciatic nerve can be blocked via a transgluteal (needle inserted just distal and deep to gluteus maximus muscle) or infragluteal (just below the level of the subgluteal crease) approach.  For both approaches, the patient is placed in a position between lateral decubitus and prone, with the hip and knee flexed".

Serratus Plane Block for the Management of Post-Operative Pain Following Breast Surgery or Thoracotomy

Madabushi et al (2015) noted that pain following thoracotomy is of moderate-to-severe nature.  Management of thoracotomy pain is a challenging task.  Post-thoracotomy pain has acute effects in the post-operative period by affecting respiratory mechanics, which increases the morbidity.  Poorly controlled thoracotomy pain in the acute phase may also lead to the development of a chronic pain syndrome.  A young male patient underwent esophagectomy and esophago-gastric anastomosis for corrosive stricture of the esophagus.  Epidural analgesia is standard of care for patients undergoing thoracotomy.  Due to hypotension and fluid losses following surgery, he was maintained on intravenous sedato-analgesia during post-operative mechanical ventilation.  The thoracic epidural catheter that was placed pre-operatively, had developed blockage during the hospital stay.  However, during weaning from ventilation and sedation, he indicated severe pain in the thoracotomy incision.  The pain was severe enough to impair tidal breathing.  These researchers wanted to examine the efficacy of the serratus anterior plane (SAP) block in the management of thoracotomy pain.  The usefulness of SAP block has been discussed in the management of pain of rib fractures and breast surgeries.  Despite the hypothesis of its usefulness in causing anesthesia of the hemithorax, there are no available reports of clinical use for pain relief following thoracotomy.  These investigators performed the SAP block under ultrasound (US) guidance and placed a catheter for continuous infusion of local anesthetics and opioid.  The patient had significant pain relief following a single bolus of the drug.  The infusion was started thereafter, which provided excellent analgesia and facilitated an uneventful recovery.  The authors described the successful management of thoracotomy pain using the SAP block.

Ohgoshi et al (2015) noted that serratus-intercostal plane block (SIPB) is a novel US-guided thoracic wall nerve block reported recently.  These researchers performed SIPB for peri-operative analgesia together with general anesthesia in patients undergoing partial mastectomy.  They chose the patients with breast cancer of upper to lower lateral quadrant or subareolar region.  Subjects received general anesthesia followed by US-guided SIPB.  The needle was introduced in the mid-axillary line at the level of the fourth or fifth rib.  Under continuous US guidance, these investigators injected 30-ml of ropivacaine 0.375 to 0.5 % between the serratus anterior and the external intercostal muscles.  After the partial mastectomy, the area of sensory loss obtained by skin prick was extended from 5 to 6 as the number of intercostal spaces.  Analgesic effect was obtained for 12 to 24 hours.  The cephalad dermatomal paresthesia was T2.  More than 20 patients received SIPB, and no one acquired the sensory loss at T1 of dermatomal distribution.  The authors concluded that SIPB provided effective analgesia for breast surgery of upper to lower lateral quadrant and/or subareolar region.  However, it should be administered with other additional analgesic agents when axillary dissection was performed, because sensory loss of T1 was difficult to achieve.

Khalil et al (2017) stated that thoracotomy is one of the most painful surgical procedures.  In a prospective, randomized, observer-blinded, controlled study, these researchers examined the safety and effectiveness of US-guided SAPB compared with thoracic epidural analgesia (TEA) for controlling acute thoracotomy pain.  The study was performed as a single-institution study in the National Cancer Institute, Cairo University, Egypt.  All participants were cancer patients scheduled for thoracotomy.  This trial was conducted from February to December 2015.  A total of 40 patients scheduled for thoracotomy under general anesthesia were allocated randomly into 1 of 2 groups with 20 patients each; SAPB was performed before extubation with an injection of 30 ml of 0.25 % levobupivacaine followed by 5 ml/hour of 0.125 % levobupivacaine.  In the TEA group, thoracic epidural catheters were inserted pre-operatively to be activated before extubation using a lower dose regimen to the SAPB group.  Heart rate (HR), mean arterial pressure (MAP), and the visual analog pain score (VAS) measurements were recorded for 24 hours.  Rescue analgesia using IV morphine, 0.1 ml/kg, was administered if the VAS was greater than 3.  Compared with pre-operative values, the MAP in the SAPB group did not change significantly (p = 0.181), whereas it decreased significantly (p = 0.006) in the TEA group; VAS scores and the total dose of morphine consumed were comparable in the 2 groups.  The authors concluded that SAPB appeared to be a safe and effective alternative for post-operative analgesia after thoracotomy.  This study did not compare US-guidance versus no US-guidance.

Sir et al (2019) noted that SAPB has been used for pain management during the acute period of conditions affecting the thorax, such as post-thoracotomy recovery, rib fracture, and breast surgery recovery.  These investigators reported the use of SAPB in post-traumatic chronic pain treatment.  They e described a case of post-traumatic chronic intercostal neuralgia, in which successful pain relief was achieved via repeated injections of local anesthetic and steroid combinations in the serratus anterior plane under US-guidance.  The authors concluded that this novel technique was easy to administer, reliable, and warrants further investigation with regard to its use for rehabilitation of patients who are suffering from post-traumatic chronic neuropathies of the chest wall.

Vig et al (2019) noted that post-thoracotomy pain is one of the most severe forms of post-operative pain.  Anesthetists usually manage post-thoracotomy pain with an epidural or para-vertebral block.  However, both of these techniques have their limitations; US-guided inter-fascial plane block like SAPB is a new concept and is proposed to provide analgesia to the hemithorax.  These investigators reported their experience with 10 thoracotomy cases where this block was used as a post-operative analgesic technique.  Patients undergoing pulmonary metastasectomy or lobectomy received US-guided SAPB between the serratus anterior and the external intercostal muscles with 0.25 % ropivacaine, and a catheter was inserted.  Post-operatively, 0.125 % ropivacaine with fentanyl (1 ug/ml) was given as infusion at 5 to7 ml/hour.  Other analgesics were paracetamol and diclofenac.  Fentanyl infusion at 0.25 ug/kg/hour was the rescue analgesic if pain persisted; 4 out of 10 patients required fentanyl infusion.  Uncontrolled pain in 2 of these patients was at the intercostal drain site; in the third patient, 2 ribs were resected; and in the fourth patient, there was poor drug spread and the catheter could not be placed in the desired plane due to poor muscle mass.  The catheter was kept in-situ for a minimum of 48 hours to a maximum of 6 days after surgery.  The authors concluded that SAPB could be an attractive option for post-thoracotomy analgesia.; further studies can take the help of the surgeon for catheter placement in the desired plane at the time of wound closure to ensure adequate drug spread.

In a prospective, randomized, single-blind study, Kaushal et al (2019) compared the relative efficacy of US-guided SAPB, pectoral nerves (Pecs) II block, and intercostal nerve block (ICNB) for the management of post-thoracotomy pain in pediatric cardiac surgery.  This trial was conducted in a single-institution tertiary referral cardiac center, and comprised 108 children with congenital heart disease requiring surgery through a thoracotomy.  Children were allocated randomly to 1 of the 3 groups: SAPB, Pecs II, or ICNB.  All participants received 3 mg/kg of 0.2 % ropivacaine for US-guided block after induction of anesthesia.  Post-operatively, IV paracetamol was used for multi-modal and fentanyl was used for rescue analgesia.  A modified objective pain score (MOPS) was evaluated at 1, 2, 4, 6, 8, 10, and 12 hours post-extubation.  The early mean MOPS at 1, 2, and 4 hours was similar in the 3 groups.  The late mean MOPS was significantly lower in the SAPB group compared with that of the ICNB group (p < 0.001).  The Pecs II group also had a lower MOPS compared with the ICNB group at 6, 8, and 10 hours (p < 0.001), but the MOPS was comparable at hour 12 (p = 0.301).  The requirement for rescue fentanyl was significantly higher in ICNB group in contrast to the SAPB and Pecs II groups.  The authors concluded that SAPB and Pecs II fascial plane blocks were equally efficacious in post-thoracotomy pain management compared with ICNB, but they had the additional benefit of being longer lasting and were as easily performed as the traditional ICNB.  This study did not compare US-guidance versus no US-guidance.

Southgate and Herbst (2021) stated that approximately 10 % of injured patients presenting to the emergency department (ED) are found to have rib fractures.  Rib fractures are associated with significant morbidity and mortality, especially in the elderly.  Pulmonary complications, including pneumonia, often become apparent 2 to 3 days after injury, when respiratory function is compromised, secondary to pain.  Thus, effective analgesia is an important component of rib fracture management; IV opioids are a mainstay of treatment but have side effects including respiratory depression, depressed cough reflex, and delirium in the elderly.  The US-guided SAPB is an alternative that has become popular due to its efficacy, relative ease, and limited side-effect profile.

Wang et al (2019) stated that reports of post-operative pain treatment after uni-portal video-assisted thoracoscopic surgery (VATS) are limited.  Thoracic para-vertebral block and SAPB have been described recently in pain management after thoracic surgery.  A comparison between these 2 blocks for post-operative analgesia after uni-portal VATS has not been previously reported.  In a retrospective, propensity-matched study, these researchers compared the analgesic benefits of SAPB and thoracic para-vertebral block after uni-portal VATS and examined the 2 block types for non-inferiority.  From December 2015 to May 2018, a total of 636 relevant records of patients who underwent uni-portal VATS under general anesthesia alone or with the addition of SAPB or thoracic para-vertebral block performed pre-operatively were identified.  A propensity-matched analysis incorporating pre-operative variables was used to compare the efficacy of post-operative analgesia in 3 groups.  A total of 123 patients were identified for analysis.  Propensity score matching resulted in 41 patients in each group.  The VAS scores were significantly lower in the SAPB group and the thoracic para-vertebral block group than in the control group at the first, second, fourth, and sixth post-operative hours.  Cumulative opioid consumption was significantly lower in the SAPB and thoracic para-vertebral block groups than in the control group at 6 hours (18.3 ± 3.1 mg, 18.7 ± 3.9 mg versus 21.5 ± 4.4 mg; p = 0.001) and 24 hours (43.4 ± 7.3 mg, 42.5 ± 7.7 mg versus 49.3 ± 8.8 mg; p < 0.001) post-operatively.  The SAPB group was non-inferior to the thoracic para-vertebral block group on pain score and opioid consumption.  The authors concluded that the findings of this study suggested that in patients undergoing uni-polar VATS, the addition of single-injection SAPB or thoracic para-vertebral block was associated with early analgesic benefits, including a reduction in post-operative opioid consumption and VAS score.  These researchers stated that SAPB was as effective as thoracic para-vertebral block in reducing post-operative pain.  Compared to thoracic para-vertebral block, SAPB is advantageous due to its relative ease of application.  Moreover, they stated that although SAP block could be an effective therapeutic option for post-operative uni-polar VATS analgesia, further prospective, large-scale, randomized controlled trials are needed to examine the efficacy of and indications for SAPB.

In a randomized controlled trial, Reyad et al (2020) examined US-guided SAPB versus patient-controlled analgesia (PCA) on the emergence of post-thoracotomy pain syndrome (PTPS) after thoracotomies for thoracic tumors.  This trial included 89 patients with chest malignancies, scheduled for thoracotomy were randomly allocated into 2 groups: Group A "PCA-group; n = 44" receiving patient-controlled analgesia; and group B "SAPB group; n = 45" where analgesia was provided by SAPB.  The primary outcome measure was the assessment for the possible emergence of PTPS at 12 weeks.  The secondary outcome measures were pain relief measured using VAS score.  Quality of life (QOL) was assessed using Flanagan QOL Scale (QOLS) and activity level was assessed using Barthel Activity of daily living (ADL) score.  At week 8, PTPS incidence was significantly (p = 0.037) higher in the PCA group (45 %) than in the SAPB group (24 %) with a relative risk (RR) of 1.38 and 95 % confidence interval (CI): 1.01 to 1.9; while the incidence of PTPS at week 12 was significantly (p = 0.035) higher in the PCA group (43 %) than in the SAPB group (22 %) with a RR of 2.38 and 95 % CI: 1.23 to 4.57.  The need for pain therapy in PTPS patients was significantly lower in the SAPB group (17.7 %) than the PCA group (38.6 %) (p = 0.028) at week 12.  Pain intensity: VAS-R and VAS-D (pain scores at rest and with activity, respectively) was comparable (p > 0.05) between both groups at 6, 12, 18 and 24 hours, however VAS was significantly higher in the PCA group at week 8 (p = 0.046) and week 12 (p = 0.032).  Both groups were comparable regarding ADL and QOL scores (p > 0.05).  The authors concluded that SAPB is assumed to be a good alternative for post-thoracotomy analgesia following thoracotomies.  The current work hypothesized that SAPB for a week post-operatively, may reduce the emergence of PTPS and may reduce the demand for pain therapy in those patients.

Hanley et al (2020) stated that the deep SAPB is a promising novel regional anesthesia technique for blockade of the antero-lateral chest wall.  Evidence for the efficacy of SAPB versus other analgesic techniques in thoracic surgery remains inadequate.  In a randomized, double-blinded, single-center, non-inferiority study, these researchers compared US-guided continuous SAPB with a surgically placed continuous thoracic para-vertebral block (SPVB) technique in patients undergoing VATS.  These investigators allocated 40 patients undergoing VATS to either SAPB or SPVB, with both groups receiving otherwise standardized treatment, including multi-modal analgesia.  The primary outcome was 48-hour opioid consumption; secondary outcomes included numerical rating scale (NRS) for post-operative pain, patient-reported worst pain score (WPS) as well as functional measures (including mobilization distance and cough strength).  A 48-hour opioid consumption for the SAPB group was non-inferior compared with SPVB.  SAPB was associated with improved NRS pain scores at rest, with cough and with movement at 24 hours post-operatively (p = 0.007, p = 0.001 and p = 0.012, respectively).  SAPB was also associated with a lower WPS (p = 0.008).  Day 1 walking distance was improved in the SAPB group (p = 0.012), whereas the difference in cough strength did not reach statistical significance (p = 0.071).  There was no difference in hemodynamics, opioid side effects, length of hospital stay or patient satisfaction between the 2 groups.  The authors concluded that SAPB, as part of a multi-modal analgesia regimen, was non-inferior in terms of 48-hour opioid consumption compared to SPVB and was associated with improved functional measures in thoracic surgical patients.

Furthermore, an UpToDate review on "Thoracic nerve block techniques" (Rosenblatt and Lai, 2020b) states that "Thoracic interfascial plane blocks include the Pecs I, Pecs II, serratus plane (SP), transversus thoracic muscle plane (TTMP), and erector spinae (ESP) blocks.  These blocks can be utilized for superficial and deep surgery in the chest wall and axillary regions (e.g., mastectomy, cosmetic breast surgery, chest tube placement, multiple rib fractures).  We suggest the use of ultrasound guidance for TPVB and the interfascial plane blocks of the chest (Grade 2C), to increase the success rate and reduce complications".  It also states that "The SP block is designed to anesthetize the thoracic intercostal nerves in order to provide analgesia for the lateral chest wall.  Intercostal nerves from T2 to T9 are usually blocked.  The SP block is a more posterior and lateral modification of the Pecs II block; they are not performed together.  However, the Pecs I injection must be added to the SP block for breast reconstruction or surgery that violates the anterior chest wall, to block the medial and lateral pectoral nerves.  The SP block is performed using ultrasound guidance".

Supraclavicular Nerve Block for Primary Regional Anesthesia During Surgeries / Post-Operative Pain Control

Karaman et al (2019) compared the effects of supraclavicular brachial plexus block (SCBPB) with ISBPB in terms of post-operative pain and quality of recovery after ASS.  A total of 62 adult patients scheduled for ASS under general anesthesia were randomized into 2 groups to receive either ISBPB (IB group, n = 31) or SCBPB (SB group, n = 29) with 20-ml of 0.25 % bupivacaine under US guidance.  Assessments included post-operative pain scores, additional analgesic requirement, timing of the first analgesic requirement, quality of recovery-40 (QoR-40) scores, block characteristics, and side effects.  No significant differences were found between the 2 groups for pain scores (p = 0.34), timing of first analgesic requirement (p = 0.30), additional analgesic requirement (p = 0.34), or QoR-40 (p = 0.13) scores.  The block characteristics regarding procedure time (p = 0.95), block failure, and onset time of sensory blockade (p = 0.33) were similar.  Horner's syndrome occurred in 8 patients in the ISBPB group and 1 patient in the SCBPB group (p = 0.015).  The authors concluded that this study showed that US-guided SCBPB was as effective as ISBPB in reducing post-operative pain and improving the quality of recovery for ASS.

Furthermore, an UpToDate review on "Upper extremity nerve blocks: Techniques" (Jeng and Rosenblatt, 2019b) states that "The supraclavicular approach blocks the brachial plexus at the level of the nerve trunks (upper, middle, and lower), where the nerves are packed closely together.  Supraclavicular block provides a reliable, rapid onset and dense block for surgery of the distal two-thirds of the upper extremity, including those surgeries requiring an upper extremity tourniquet (e.g., hand surgery) … Ultrasound-guided supraclavicular block – We suggest the use of ultrasound guidance whenever a supraclavicular block is performed in order to minimize the chance of vascular puncture and pneumothorax.  The ultrasound transducer is placed in a transverse position parallel to and just above the clavicle.  The subclavian artery is identified by moving the transducer medially along the clavicle and directing the transducer toward the first rib.  The brachial plexus at the level of the trunks and divisions appears as a "bundle of grapes" lateral to the subclavian artery.  The lateral end of the transducer is often rotated slightly cephalad to visualize the brachial plexus in a more short-axis plane (perpendicular to its path).  The needle is inserted in-plane from lateral to medial (parallel to the transducer), with the target being the junction of the subclavian artery, brachial plexus, and first rib ("corner pocket") and LA is injected to lift the brachial plexus off the first rib.  Twenty to 30 mL of LA is injected, after negative aspiration for blood, in 5-mL increments, while looking for spread around the nerves.  Most practitioners prefer a two-injection technique, with one-half of the LA deposited at the "corner pocket" and the other one-half deposited more superficially between trunks of the plexus or above the plexus.  Injection should be stopped if the patient experiences pain or paresthesia".

An UpToDate review on “Overview of anesthesia” (Falk and Fleisher, 2021) states that “Peripheral nerve blocks are widely-used for surgical anesthesia, particularly for procedures in an upper or lower extremity.  Ultrasound guidance with or without a nerve stimulator is typically used for placement of a needle or catheter”.

Tendon Sheath Injection of Pectoralis Minor

Sandhu and Capan (2002) noted that peripheral nerve blocks are almost always carried out as blind procedures.  These researchers tested the feasibility of seeing individual nerves of the brachial plexus and directing the block needle to these nerves with real-time imaging.  Using US guidance, infra-clavicular brachial plexus block was carried out in 126 patients.  Important aspects of this standardized technique included imaging the axillary artery and the 3 cords of the brachial plexus posterior to the pectoralis minor muscle; marking the position of the US probe before introducing a Tuohy needle; maintaining the image of the entire length of the needle at all times during its advancement; depositing local anesthetic around each of the 3 cords; and placing a catheter anterior to the posterior cord when indicated.  In 114 (90.4 %) patients, an excellent block permitted surgery without a need for any supplemental anesthetic or conversion to general anesthesia.  In 9 (7.2 %) patients, local or perineural administration of local anesthetic, and in 3 (2.4 %) conversion to general anesthesia, was required.  Mean times to administer the block, onset of block and complete block were 10.0 (SD 4.4), 3.0 (1.3) and 6.7 (3.2) mins, respectively.  Mean lidocaine dose was 695 (107) mg.  In 1 patient, vascular puncture occurred.  In 53 (42.6 %) patients, an indwelling catheter was placed, but only 3 required repeat injections, which successfully prolonged the block.  The authors concluded that the use of US appeared to permit accurate deposition of the local anesthetic perineurally; and had the potential to improve the success and decrease the complications of infra-clavicular brachial plexus block.

Bailey et al (2021) stated that the costo-clavicular block is a relatively novel alternative to the infra-clavicular block.  In a cadaveric study, these researchers determined the anatomical structures vulnerable to needle injury during a costo-clavicular block.  The needle path consistent with a costo-clavicular block approach was carried out bilaterally on 4 lightly embalmed cadavers using US guidance.  Careful dissection was performed with 18-G Tuohy needles in-situ and photographs were taken.  The needle penetrated the deltoid in 6 of 8 cases and the pectoralis minor in 3 of 8 cases.  The subclavius tendon or its fascia were punctured in 2 of 8 cases.  The lateral cord was in contact with the needle in 6 procedures and punctured in 3.  The posterior cord was contacted in 2 instances, and the medial cord in 1.  In a single dissection, the needle was in contact with the medial antebrachial cutaneous nerve.  The needle was close to the medial brachial cutaneous nerve in 1 case and close to the pectoral nerves in 2 of 8 cases.  While the cephalic vein and thoraco-acromial artery were consistently nearby, there were no cases of vascular puncture.  The authors found that the needle path may be close to the medial antebrachial cutaneous nerve, medial brachial cutaneous nerve, and pectoral nerves; but did not traverse any critical structures aside from the lateral cord, suggesting relative safety when compared with other approaches to the infra-clavicular brachial plexus.

Transverse Abdominis Plane (TAP)-Block for the Management of Post-Operative Pain following Abdominal Surgery

Wang et al (2016) stated that US-guided ilio-inguinal/ilio-hypogastric (II/IH) nerve and transversus abdominis plane (TAP) blocks have been increasingly utilized in patients for peri-operative analgesia.  In a meta-analysis, these researchers examined the clinical efficacy of US-guided II/IH nerve or TAP blocks for peri-operative analgesia in patients undergoing open inguinal surgery.  A systematic search was conducted of 7 data-bases from the inception to March 5, 2015.  Randomized controlled trials (RCTs) comparing the clinical efficacy of US-guided versus landmark-based techniques to perform II/IH nerve and TAP blocks in patients with open inguinal surgery were included.  These investigators constructed random effects models to pool the standardized mean difference (SMD) for continuous outcomes and the odds ratio (OR) for dichotomized outcomes.  Ultrasound-guided II/IH nerve or TAP blocks were associated with a reduced use of intra-operative additional analgesia and a significant reduction of pain scores during day-stay.  The use of rescue drugs was also significantly lower in the US-guided group.  The authors concluded that the use of US-guidance to perform an II/IH nerve or a TAP block was associated with improved peri-operative analgesia in patients following open inguinal surgery compared to landmark-based methods.

Park et al (2017) stated that TAP block has been used as a component of multi-modal analgesia after abdominal operation.  These researchers introduced a new laparoscope-assisted TAP (LTAP) block technique using intra-peritoneal injection and compared its analgesic effect with that of an US-guided TAP (UTAP) block in terms of post-operative pain control.  They carried out a prospective, randomized, single-blinded non-inferiority clinical trial with patients undergoing elective laparoscopic colectomy for colon cancer; 80 patients were randomly assigned (1:1 ratio) to the UTAP and LTAP groups.  At the end of the operation, opioid consumption and numeric rating scores (NRS; 0 [no pain] to 10 [worst pain]) of pain were recorded at 2, 6, 24, and 48 hours post-operatively and were compared between the groups.  The primary end-point was pain NRS during rest at 24 hours after operation.  A total of 38 patients in the LTAP group and 35 patients in the UTAP group completed the study protocol.  These investigators found no significant difference in mean ± SD pain NRS during rest at 24 hours between the LTAP group (3.90 ± 1.7) and the UTAP group (4.5 ± 1.9).  The mean difference (MD) in pain NRS during rest at 24 hours was 0.57 (95 % confidence interval [CI]: -0.26 to 1.41).  Because the lower boundary of a 95 % CI for the differences in pain NRS was greater than -1, non-inferiority was established.  There was no significant difference between the groups in NRS pain during rest, NRS pain on movement, and post-operative morphine consumption during the 48 hours after operation.  The authors concluded that these findings demonstrated that their new LTAP block technique was non-inferior to the US-guided technique in providing a TAP block after laparoscopic colorectal operation.

Kim et al (2017) stated that the concepts of enhanced recovery after surgery (ERAS) have steadily increased in usage, with benefits in patient outcomes and hospital length of stay (LOS).  One important component of successful implementation of ERAS protocol is optimized pain control, via the multi-modal approach, which includes neuraxial or regional anesthesia techniques and reduction of opioid use as the primary analgesic; and TAP block is one such regional anesthesia technique, and it has been widely studied in abdominal surgery.  These investigators conducted a literature search in Medline and PubMed, and reviewed the benefits of TAP blocks for colorectal surgery, both laparoscopic and open.  They organized the data by surgery type, by method of TAP block performance, and by a comparison of TAP block to alternative analgesic techniques or to placebo.  These researchers examined different end-points, such as post-operative pain, analgesic use, return of bowel function, and LOS.  The majority of studies examined TAP blocks in the context of laparoscopic colorectal surgery, with many, but not all, demonstrating significantly less use of post-operative opioids in comparison to placebo, wound infiltration, and standard post-operative patient-controlled analgesia (PCA) with intravenous opioid administration.  There was evidence that use of liposomal bupivacaine may be more effective than conventional long-acting local anesthetics.  Non-inferiority of TAP infusions has been demonstrated, compared with continuous thoracic epidural infusions.  The authors concluded that TAP blocks were easily performed, cost-effective, and an opioid-sparing adjunct for laparoscopic colorectal surgery, with minimal procedure-related morbidity.  The evidence was in concordance with several of the goals of ERAS pathways.  Moreover, this review did not mention the use of US-guidance for TAP block.

Doble et al (2018) stated that TAP blockade with long-acting anesthetic can be used during open ventral hernia repair (VHR) with posterior component separation (PCS).  TAP block can be performed under US guidance (US-TAP) or under direct visualization (DV-TAP).  These researchers hypothesized that US-TAP and DV-TAP provide equivalent post-operative analgesia following open VHR.  They carried out a retrospective review of patients undergoing open VHR with PCS who received TAP blocks with 266-mg of liposomal bupivacaine.  Data included demographics, co-morbidities, LOS, average post-operative day (POD) pain scores, and narcotic requirements (normalized to mg oral morphine).  Statistical analysis utilized Student's t test and Fisher's exact test.  A total of 39 patients were identified (22 DV-TAP).  There were no differences between the groups with respect to demographics, co-morbidities, pre-operative pain medication usage (narcotic and non-narcotic) or herniorrhaphy-related data.  The average POD0 pain score was lower for the DV-TAP group (2.35 versus 4.18; p = 0.019).  Narcotic requirements on POD0 (48.0 versus 103.76 mg; p = 0.02), POD1 (128.45 versus 273.82 mg; p = 0.03), POD4 (54.29 versus 160.75 mg; p = 0.042), and during the complete hospitalization (408.52 versus 860.92 mg; p = 0.013) were lower in the DV-TAP group.  There were no differences between initiation of diet or LOS.  During the study, no changes were made to the VHR enhanced recovery pathway.  The authors concluded that DV-TAP blocks appeared to provide superior analgesia in the immediate post-operative period.  To achieve similar post-operative pain scores, patients in the US-TAP group required significantly more narcotic administration during their hospitalization.  The study highlighted DV-TAP as a valuable addition to VHR recovery pathways.

Kakade and Wagh (2019) noted that TAP block is a fascial plane block providing post-operative analgesia after lower abdominal surgeries including Cesarean section.  Conventionally, it is administered under US guidance or by blind technique.  These researchers examined a novel trans-peritoneal surgical TAP block for providing safe and effective analgesia after Cesarean section through transverse incision.  A total of 100 patients who fulfilled the inclusion criteria were included in the study after obtaining informed written consent.  They were randomized in 2 groups: Group A with surgical TAP block and Group B without TAP block as control.  Surgical TAP block was administered by trans-peritoneal route before the closure of peritoneum with 0.25 % bupivacaine (dose adjusted with weight of the patient), and VAS was assessed by a blind assessor.  Time for rescue analgesia was noted and analyzed with the "2 independent sample t-test".  The duration of post-operative analgesia in hours was significantly longer in the TAP block group compared with the control group (5.14 ± 1.63 versus 2.61 ± 0.89, p < 0.001).  There was no reported complication of the surgical technique or any adverse effect of the used drug.  The authors concluded that surgical TAP block via the trans-peritoneal route is a safe, easy and effective mode of providing post-operative analgesia after Cesarean section.  This technique did not need any costly specialist equipment, overcame the technical limitations of US-guided TAP block and could be used in obese patients also.  It had almost no side effects, and the technique could be easily mastered.

Vonu et al (2020) stated that there are a variety of regional nerve blocks that have been utilized in abdominoplasty procedures including transversus abdominis plane (TAP), intercostal, rectus sheath (RS), pararectus + II/IH, quadratus lumborum, and paravertebral blocks.  No consensus exists regarding the most effective nerve block modality in optimizing post-procedural comfort levels.  In a systematic review, these researchers examined the efficacy of the various abdominal nerve blocks used in abdominoplasty surgery, and drew attention to any modality that may be superior in regards to effectiveness and/or administration.  Using PRISMA guidelines, a systematic review was performed to identify studies that have used regional nerve blocks in abdominoplasty procedures.  Opioid consumption, pain scores, time to ambulation, time in the recovery room, and time to first analgesia request were extracted when available.  A total of 191 articles were reviewed of which 8 met inclusion criteria.  The nerve blocks represented included TAP, RS, pararectus + II/IH, intercostal, and quadratus lumborum.  All modalities were effective in reducing opioid consumption except quadratus lumborum.  The authors concluded that TAP, RS, pararectus + II/IH, and intercostal regional nerve blocks have been shown to optimize post-operative pain management in abdominoplasty procedures.  When studied against one another, the existing literature suggested that TAP is more effective than RS and pararectus + II/IH.  These researchers noted that when US guidance is unavailable, consideration should be given to TAP using the direct visualization approach.

Wong et al (2020) noted that TAP block is an important non-narcotic adjunct for post-operative pain control in abdominal surgery.  Surgeons can use LTAP, however, direct comparisons to conventional UTAPs have been lacking.  In a prospective, randomized, patient- and observer-blinded, parallel-arm, non-inferiority trial, these researchers examined if surgeon-placed LTAPs were non-inferior to anesthesia-placed UTAPs for post-operative pain control in laparoscopic colorectal surgery.  This study was performed at a single tertiary academic center between 2016 and 2018 on adult patients undergoing laparoscopic colorectal surgery.  Narcotic consumption and pain scores were compared for LTAP versus UTAP for 48 hours post-operatively.  A total of 60 patients completed the trial (31 UTAP, 29 LTAP) of which 25 patients were women (15 UTAP, 10 LTAP) and the mean ages (SD) were 60.0 (13.6) and 61.5 (14.3) in the UTAP and LTAP groups, respectively.  There was no significant difference in post-operative narcotic consumption between UTAP and LTAP at the time of PACU discharge (median inter-quartile range [IQR] milligrams of morphine, 1.8 [0 to 4.5] UTAP versus 0 [0 to 8.7] LTAP; p = 0.32), 6 hours post-operatively (5.4 [1.8 to 17.1] UTAP versus 3.6 [0 to 12.6] LTAP; p = 0.28), at 12 hours post-operatively (9.0 [3.6 to 29.4] UTAP versus 7.2 [0.9 to 22.5] LTAP; p = 0.51), at 24 hours post-operatively (9.0 [3.6 to 29.4] UTAP versus 7.2 [0.9 to 22.5] LTAP; p = 0.63), and 48 hours post-operatively (39.9 [7.5 to 70.2] UTAP versus 22.2 [7.5 to 63.8] LTAP; p = 0.41).  Patient-reported pain scores as well as pre-, intra-, and post-operative course were similar between groups.  Non-inferiority criteria were met at all post-operative time-points up to and including 24 hours but not at 48 hours.  The authors concluded that surgeon-delivered LTAPs were safe, effective, and non-inferior to anesthesia-administered UTAPs in the immediate post-operative period.  These investigators stated that this method (surgeon-placed LTAPs) should be considered in all patients undergoing laparoscopic colorectal surgery where an US-guided TAP block is planned.

Furthermore, an UpToDate review on "Abdominal nerve block techniques" (Rosenblatt and Lai, 2020a) states that "We perform TAP blocks with ultrasound guidance, though TAP block was first described using anatomic landmarks.  TAP blocks can also be placed under direct vision by the surgeon during laparoscopy or laparotomy … We suggest using ultrasound guidance rather than anatomic landmarks to perform abdominal blocks (Grade 2C) to increase the success rate and reduce complications ".

Ultrasound Guidance: Experimental and Investigational Indications

Adductor Brevis and Pectineus Tendon Injection for Pain Relief

Sinha et al (2009) noted that for knee surgery, obturator nerve block (ONB) has been shown to enhance post-operative analgesia provided by femoral block.  Current techniques for ONB employ surface landmarks or USG with nerve stimulation.  In an observational, preliminary study, these researchers examined the success of an USG-ONB without the additional use of nerve stimulation.  A total of 30 patients scheduled for knee surgery under general anesthesia with nerve block for post-operative analgesia had ONB performed using USG and injection of 10 ml 0.5 % ropivacaine with epinephrine.  Half of the ropivacaine was injected between the pectineus and adductor brevis muscles, and half between the adductor brevis and adductor magnus muscles.  The strength of thigh adduction was measured at 5, 10, and 15 mins after injection, and 50 % strength reduction at 15 mins indicated a successful block.  All patients showed reduction of strength, and 28 of 30 (93 %) met the criteria for successful block with mean strength reduction of 82.2 % (SD, 21.6 %) at 15 mins; blocks were completed in 122 secs (SD, 33 secs).  The authors concluded that ONB using USG to achieve inter-fascial injection without nerve stimulation had success similar to that reported in studies using nerve stimulation.

Manassero et al (2012) stated that inter-fascial injection of LA under US guidance has been proposed as a new technique for performing an ONB.  These researchers hypothesized that inter-fascial needle placement could supplant nerve stimulation as the endpoint for LA injection during USG-ONB after the division of the obturator nerve.  A total of 50 spinal anesthesia patients who had experienced unilateral adductor muscle spasm during transurethral bladder tumor resection were randomly allocated to receive either 5-ml of lidocaine 2 % injected under USG into the inter-fascial plane between the adductor longus and the adductor brevis and between the adductor brevis and the magnus muscles (US group) or an injection of 5-ml of lidocaine 2 % in combination with nerve stimulation after identification of the divisions of the obturator nerve (USENS group).  At 5, 10, and 15 mins after block placement, muscle spasm was evaluated by an independent observer masked to treatment allocation.  The primary outcome was motor block onset time; secondary outcomes were block performance time, total anesthesia-related time, motor block success at 15 mins, and number of needle passes.  Motor block onset time did not differ between the 2 groups (6.2 mins for USENS versus 7.2 mins for US group, p = 0.225), block performance time was longer in the USENS than in the US group (3.0 versus 1.6 mins, p < 0.001), and total anesthesia-related time did not differ between the 2 groups (9.2 versus 8.9 mins, p = 0.71).  Block success rate at 15 mins was 100 % in the USENS group and 88 % in the US group (p = 0.23).  There was no difference in the number of needle passes (2.3 versus 2.1, p = 0.28).  The authors concluded that in USG-ONB performed after the division of the nerve, injection of LA between the planes of the adductor muscles was comparable to nerve stimulation.

Akkaya et al (2009) stated that ONB is one of the most technically challenging regional anesthesia techniques.  Recently, the characteristics of the nerve have been described using US; however, clinical application of proximal USG-ONB on patients has not been reported.  These researchers employed US to describe the anatomical localization of the obturator nerve and its 2 branches in cadavers, volunteers, and also patients.  A hyperechoic triangular shape formed by the superior pubic ramus, posterior margin of the pectineus muscle and anterior aspect of the external obturator muscle containing the obturator vessels and nerve was defined by US imaging in cadavers.  In 8 volunteers, bilateral obturator nerve images were obtained and the distances to specific landmarks (femoral artery, femoral vein, and pubic tubercle) were recorded.  USG-ONB was carried out in 15 patients by using the previously defined approach.  The final distance of the needle tip to the femoral artery, distances between the needle insertion point to the pubic tubercle and the depth of needle insertion were recorded.  The rates of common obturator nerve, anterior and branching obturator nerve pattern visibility with US were determined in 12/16, 13/16, and 7/16 sites in volunteers, respectively.  Mean (SD) values of critical landmarks obtained from volunteers were obturator nerve-femoral vein 12.9 +/- 2.9 mm and obturator nerve-pubic tubercle 19.9 +/- 2.6 mm.  Mean measurements obtained from patients were -- femoral artery-needle tip 18.5 +/- 2.4 mm, needle depth 48.3 +/- 10.4 mm, pubic tubercle-needle insertion point (horizontal) 18.8 +/- 2.0 mm, and pubic tubercle-needle insertion point (vertical) 21.1 +/- 2.9 mm.  VAS scores obtained from patients at 1 and 24 hour(s) were lower compared to baseline values (p < 0.001); 14 of 15 (93 %) of the patients reported satisfaction from the block.  The authors concluded that landmarks defined in this clinical trial could be used in patients for ONB with US guidance.

These investigators stated that the main drawback of this study was the lack of a control group in which only a peripheral nerve stimulator was used.  They stated further studies are needed to determine the relative safety and effectiveness of this technique to previously described approaches.

Yosida et al (2016) examined an alternative technique for US-guided proximal level ONB that might facilitate needle visualization using in-plane US guidance.  A total of 20 patients undergoing trans-urethral bladder tumor resection requiring an ONB were enrolled into a prospective, observational study.  With the patient in the lithotomy position, the transducer was placed on the medial thigh along the extended line of the inguinal crease; and aimed cephalad to view a thick fascia between the pectineus and obturator externus muscles that contains the obturator nerve.  A stimulating nerve block needle was inserted at the pubic region and advanced in-plane with the transducer in an anterior-to-posterior direction; 8-ml of levobupivacaine 0.75 % was injected within the fascia.  The median (IQR duration for US identification of the target and injection were 8.5 (7 to 12 [5 to 24]) s and 62 (44.5 to 78.25 [39 to 383]) s, respectively.  All blocks were successful.  A cadaver evaluation demonstrated that the dye injected into the target fascia using our technique travelled retrogradely via the obturator canal; and surrounded the anterior and posterior branches of the obturator nerve both proximally and distally to the obturator canal.  The authors concluded that that the US-guided pubic obturator nerve block approach is a promising technique that might facilitate real-time needle visualization with the in-plane approach.  Moreover, these researchers stated that further studies are needed to demonstrate the superiority of this technique compared with other proximal obturator nerve block techniques.

Adductor Longus Tendon Injection

In a pilot study, Dallaudiere et al (2014) examined the potential therapeutic effect of intra-tendinous injection of platelet-rich plasma (PRP) under ultrasound (US) guidance to treat tendon tears and tendinosis with long-term follow-up.  The study included 408 consecutive patients referred for treatment by PRP injection of tendinopathy in the upper (medial and lateral epicondylar tendons) and the lower (patellar, Achilles, hamstring and adductor longus, and peroneal tendons) limb who received a single intra-tendinous injection of PRP under US guidance.  Clinical and US data were retrospectively collected for each anatomic compartment for upper and lower limbs before treatment (baseline) and 6 weeks after treatment.  Late clinical data without US were collected until 32 months after the procedure (mean of 20.2 months).  The McNemar test and regression model were used to compare clinical and US data.  QuickDASH score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and residual US size of lesions were significantly lower after intra-tendinous injection of PRP under US guidance at 6 weeks and during long-term follow-up compared with baseline (p < 0.001 in upper and lower limb) independent of age, gender, and type of tendinopathy (p > 0.29).  No clinical complication was reported during follow-up.  The authors concluded that intra-tendinous injection of PRP under US guidance appeared to allow rapid tendon healing and was well-tolerated. Note: Per CPB 0784 - Blood and Adipose Product Injections for Selected Indications, we do not cover PRP injection for any indication.

Bisciotti et al (2021) stated that chronic adductor-related groin pain syndrome is a widely common problem for athletes in many sports activities that often drastically reduces player activity and performance.  The 1st-line of treatment is conservative therapy.  These investigators provided a systematic review regarding conservative treatment for chronic adductor-related groin pain syndrome present in literature today.  Furthermore, they rendered a critical vision of the current state of the art of the considered topic.  After screening 234 articles, a total of 19 studies following the inclusion criteria were included and summarized in this current systematic review and 7 different types of therapeutic interventions were described.  Compression clothing therapy, manual therapy together with strengthening exercise and prolotherapy were the therapeutic interventions that showed both the greatest level of strength of evidence (Moderate) and grade of recommendation (D).  The remaining 4 types of therapeutic interventions i.e., corticoid injection, PRP therapy, intra-tissue percutaneous electrolysis and pulse-dose radiofrequency, showed both lower levels of strength of evidence (conflicting) and grade of recommendation (C).  The authors concluded that the literature available on the conservative treatment for chronic adductor-related groin pain syndrome was limited and characterized by a low-level of evidence; thus, their recommendation was to refer only to the few studies with higher level of evidence and at the same time to encourage further research in this area.  The intervention showing the greater level of strength of evidence, and the greater grade of recommendation are compression clothing therapy, manual therapy and strengthening exercise, and prolotherapy.  Other therapeutic interventions such as intra-tissue percutaneous electrolysis and pulse-dose radiofrequency appeared promising but require further studies to confirm their efficacy.  This review did not mention US guidance for injections.

Furthermore, an UpToDate review on “Adductor muscle and tendon injury” (Patricios, 2021) does not mention ultrasound guidance as a management tool.

Ankle Bursa Injection

An UpToDate review on “Bursitis: An overview of clinical manifestations, diagnosis, and management” (Todd, 2021) states that “Imaging studies are typically not necessary, particularly in the case of superficial bursa where the signs of inflammation are demonstrated on the physical examination … Limited data suggest that ultrasound-guided injections of the subacromial bursa may be more effective than a "blind" injection; however, this was not validated in a large systematic review.  As ultrasound guidance is not available in real time in many practices, we do not advocate that the use of ultrasound-guided injections is essential”.

Anterior Medial Ankle Joint and Tibialis Posterior Tendon Sheath Injection for Foot Pain

Jose et al (2014) described a US-guided technique to carry out therapeutic injections for anteromedial ankle impingement syndrome.  Scans were performed using a high-frequency small footprint linear array transducer, positioned along the anteromedial aspect of the tibiotalar joint.  A 25-G needle was advanced under direct US guidance into the "meniscoid lesion" (area of scarring), and a standardized therapeutic mixture was injected extra-articularly.  The authors concluded that image-guided injections had a positive influence on clinical decision-making by improving patient management, increasing the accuracy of diagnosis, and decreasing patient pain.  These investigators stated that sonography allows confirmation of correct injection placement, resulting in increased accuracy and more successful patient outcomes.  Levels of Evidence = V.

In a retrospective, single-center study, Peters et al (2017) identified tendon sheaths most commonly treated with steroid injections in a pediatric patient population with JIA; described technical aspects of the procedure; characterized sonographic appearance of tenosynovitis in JIA; and examined agreement between clinical request and sites injected.  This was a 10-year trial (May 2006 to April 2016) of patients with JIA referred for US-guided tendon sheath injections.  Patient demographics, clinical referral information, sonographic appearance of the tendon sheaths and technical aspects of the procedure were analyzed.  There were 308 procedures of 244 patients (75 % female, mean age of 9.6 years) who underwent a total of 926 tendon sheath injections.  Ankle tendons were most commonly injected (84.9 %), specifically the tendon sheaths of tibialis posterior (22.3 %), peroneus longus (20 %) and brevis (19.7 %).  The majority of treated sites (91.9 %) showed peritendinous fluid and sheath thickening on US.  There were 2 minor intra-procedure complications without sequelae.  A good agreement between clinical request and sites injected was observed.  The authors concluded that US-guided tendon sheath injections with steroids were used frequently to treat patients with JIA.  It was a safe intervention with a high technical success rate.  The ankle region, specifically the medial compartment, was the site most commonly injected in this group of patients.  The most common sonographic finding was peritendinous fluid and sheath thickening.  These researchers stated that these findings might assist clinicians and radiologists to characterize and more effectively manage tenosynovitis in patients with JIA.

The authors concluded that this study had several drawbacks.  This was a retrospective, single-center study.  Occasionally images stored in Picture Archiving and Communication System (PACS) were sub-optimal and images may not have been stored for all tendon sheaths treated.  Injections occurring in the rheumatology clinic were not included in the denominator of 1,275 procedures.  In this institution tendon sheath injections without US guidance were occasionally carried out in isolated treatment of the flexor compartment of the hand.

In a single-blind RCT, Razavi et al (2021) compared the effects of landmark-guided versus US-guided intra-articular injection of corticosteroid into the 1st metatarsophalangeal (MTP) joint cavity to reduce pain and dysfunction in patients with hallux rigidus.  A total of 50 participants (35 women) with the mean (SD) age of 49.8 (10.3) years were randomly allocated to landmark-guided or US-guided groups (each n = 25).  Each patient received a single intra-articular injection of 40-mg methylprednisolone plus 1 ml lidocaine into the affected 1st MTP joint.  The primary outcome was joint pain; and the secondary outcome was the AOFAS score.  These investigators measured the outcomes at baseline and 2 and 6 weeks after the intervention.  Six weeks after the injections, there were no statistically significant differences between the study groups in pain reduction and increase in the AOFAS (p = 0.131 and 0.241, respectively).  They did not find any complications for the injections in either group.  There were statistically significant changes within each group in pain and the scores for the landmark (p < 0.001, and p = 0.007), and US groups (both p < 0.001).  The authors concluded that landmark guidance was as effective as US guidance for intra-articular injection in patients with hallux rigidus.  A single intra-articular injection of 40-mg methylprednisolone plus 1-ml lidocaine was a safe and effective therapeutic measure for reducing joint pain and maintaining its function, at least for 6 weeks.  Level of Evidence = I.

Anterior Scalene/Brachial Plexus Block for Management of Chronic Pain

Burckett-St Laurent et al (2014) noted that the conventional US-guided interscalene block targets the C5 and C6 nerve roots at approximately the level of the cricoid cartilage where they lie in the groove between the anterior and middle scalene muscles.  This technique, although effective at providing regional anesthesia of the shoulder, is associated with risks of phrenic nerve palsy, injury to the dorsal scapular and long thoracic nerves, and long-term post-operative neurologic symptoms.  In a case report, these researchers described the US-guided superior trunk block.  This procedure targets the C5 and C6 components of the brachial plexus more distally after they unite into the superior trunk but before the suprascapular nerve branches off.  They carried out an US-guided superior trunk block to provide peri-operative analgesia for ambulatory arthroscopic shoulder repair in a patient with moderate chronic obstructive pulmonary disease (COPD).  The technique, relevant sono-anatomy of the brachial plexus, and the potential advantages of the superior trunk block were discussed.  The authors concluded that the enhanced anatomical knowledge provided by US-guidance has allowed anesthesiologists to devise new block techniques and refine existing ones.  The superior trunk block is an example of this refinement and is intended as an alternative to the conventional interscalene block for anesthesia of the shoulder.  Moreover, these investigators stated that further research is planned to confirm the safety and effectiveness of the technique.

Ullah et al (2014) noted that post-operative pain may lead to adverse effects on the body, which might result in an increase in morbidity; thus, its management poses a unique challenge for the clinician.  Major shoulder surgery is associated with severe post-operative pain, and different modalities are available to manage such pain, including opioid and non-opioid analgesics, local anesthetics infiltrated into and around the shoulder joint and regional anesthesia.  All of these techniques, alone or in combination, have been used to treat post-operative pain of major shoulder surgery but with varying success.  These researchers compared the analgesic efficacy of continuous interscalene brachial plexus block (ISBPB) with parenteral opioid analgesia for pain relief after major shoulder surgery.  They searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 12), Medline (1950 to December 2012), Embase (1980 to December 2012), Web of Science (1954 to December 2012), CINAHL (1982 to December 2012) and bibliographies of published studies.  These investigators included RCTs examining the effectiveness of continuous ISBPB compared with different forms of parenteral opioid analgesia in relieving pain in adult participants undergoing elective major shoulder surgery.  Two review authors independently evaluated trial quality and extracted outcome data.  They included 2 RCTs (147 subjects); 17 subjects were excluded from 1 trial because of complications related to continuous ISBPB (n = 16) or parenteral opioid analgesia (n = 1); therefore, they had information on 130 subjects (66 in the continuous ISBPB group and 64 in the parenteral opioid group).  The studies were clinically heterogeneous.  No meta-analysis was carried out.  However, results of the 2 included studies showed better pain relief with continuous ISBPB following major shoulder surgery and a lower incidence of complications when interscalene block was performed under US guidance rather than without it.  The authors concluded that because of the small number of studies (n = 2) relevant to the subject and the high risk of bias of the selected studies, no reasonable conclusion could be drawn.

Falyar et al (2016) stated that US-guided selective C5 nerve root blocks have been described in several case reports as a safe and effective means to anesthetize the distal clavicle while maintaining innervation of the upper extremity and preserving diaphragmatic function.  In this study, cadavers were injected with 5-ml of 0.5 % methylene blue dye under US guidance to examine possible proximal and distal spread of injectate along the brachial plexus, if any.  Following the injections, the specimens were dissected and examined to determine the distribution of dye and the structures affected.  One injection revealed dye extended proximally into the epidural space, which penetrated the dura mater and was present on the spinal cord and brainstem.  Dye was noted distally to the divisions in 3 injections.  The anterior scalene muscle and phrenic nerve were stained in all 4 injections.  It appeared unlikely that local anesthetic spread was limited to the nerve root following an US-guided selective C5 nerve root injection.  Under certain conditions, intrathecal spread also appeared possible, which has major patient safety implications.  The authors concluded that additional safety measures, such as injection pressure monitoring, should be incorporated into this block, or approaches that are more distal should be considered for the acute pain management of distal clavicle fractures.

Erdogmus et al (2021) stated that peripheral nerve blocks with the use of US allow visualization of both the structures and nerves and make the block administrations safe, quick, and comfortable.  However, few publications concerning the minimum LA volume are capable of providing blocks.  These researchers ascertained the minimum effective LA volume in brachial plexus blockage administrations with an axillary approach accompanied by US in hand, elbow, and forehand operations.  The study included a total of 55 patients (classified as ASA I-II) who underwent hand surgery by administering US-guided axillary brachial plexus blockage.  The ulnar, median, and radial nerves were located, and the minimum effective LA volume was examined starting with a total of 21-ml of bupivacaine 0.5 %.  After accomplishing the blockage, the volume was decreased by 0.5 ml for each nerve.  Block administration time, block onset times, anesthesia times, and time to 1st analgesic requirement were recorded.  The minimum effective LA volume for each nerve was 2.5 ml for a total of 7.5 ml.  In comparing block administration times, there were no differences between high or low volume groups.  It was found that sensory block onset time was 17 mins for 7.5-ml and 11 mins for 21-ml; sensory block regression time was 6 hours for 7.5-ml and 10.4 hours for 21-ml, respectively.  This regression was statistically significant.  The 1st analgesic requirement was 5.8 to 16.6 hours, respectively, for each group.  The authors concluded that in the administration of an US-guided axillary block, sufficient anesthesia can be achieved by administering 2.5-ml of bupivacaine 0.5 % for each nerve.  However, it might be kept in mind that motor and sensory block onset time would be extended and regression time and time to the 1st analgesic requirement would be shorter with this volume.  Furthermore, more advanced studies must be carried out for the determination of the optimum volume that can be used.

Trujanovic et al (2022) noted that effective multi-modal analgesia techniques are needed when pigs are used as models in orthopedic human research.  Regional anesthesia is a widely used technique to provide peri-operative analgesia in animals undergoing orthopedic surgery.  The brachial plexus (BP) block is indicated to desensitize the forelimb in many species but has not been yet described in pigs.  These researchers developed an US-guided axillary approach for the BP and examined injectate spread and nerve staining in pig cadavers.  A total of 8 fresh F1 cross breed German Large White and German Landrace male pig cadavers were enrolled.  Two cadavers were used for anatomical dissection of the axillary space and for determination of the disposition of the BP; 6 cadavers were used to perform a bilateral axillary US-guided approach for the BP, and after injecting 0.3 ml/kg of a solution of 2 % lidocaine and new methylene blue (L-NMB), these were dissected to determine injectate spread and nerve staining.  Upon dissection, the BP was observed in all the cases surrounded by the axillary sheath and in close proximity to the axillary artery.  US scanning and guidance for the approach to the BP was feasible in all cadavers and upon dissection, all the nerves forming the BP were stained in all their quadrants and in all the cases.  The authors concluded that the injection of 0.3 ml/kg of L-NMB via an US-guided axillary approach to the BP was feasible and adequate to entirely stain the BP in all pig cadavers.  Moreover, these researchers stated that further clinical studies are needed to examine the effectiveness of this technique in live animals.

Aspiration and Collection of Fluid to Send for Culture from the Post-Femoropopliteal Bypass Graft Site

In a technical note, Touma et al (2019) described a total percutaneous technique to perform US and fluoroscopy-assisted femoropopliteal bypass in long superficial femoral artery (SFA) lesions, using standard equipment, via a juxta-anatomical superficial femoral vein (SFV) tunnel.  A total of 3 percutaneous accesses were obtained under US guidance.  The 1st was retrograde, with cross-over maneuver, at the contralateral groin.  The 2nd was a proximal SFV-to-SFA stump puncture.  The 3rd was a distal popliteal artery-to-popliteal vein puncture.  Through the described snaring and capture maneuvers, 1 single 0.018-inch guide-wire entered the femoral vein via the SFA stump and re-entered the popliteal artery distally.  The fistulous tracts were then dilated, and covered stents deployed and post-dilated.  A total of 3 patients aged 68 ± 3 years and presenting Rutherford Classifications (4 stages) chronic limb ischemia (CLI) were treated with this technique.  The mean SFA lesion length was 22.6 ± 3 cm.  The mean procedure duration was 88 ± 18 mins.  No intra-operative complication occurred.  The post-operative course was uneventful.  In particular, no deep vein thrombosis (DVT) occurred.  Rutherford stage decreased from 4 to 1 in all patients, with a mean follow-up duration of 6.6 ± 2 months.  The authors concluded that the main advantage of the technique was avoidance of calcification issues by abandoning the trans-arterial re-canalization approach for long calcified lesions.  The 2nd interest was its feasibility by simple endovascular means without any particular or dedicated device.  Moreover, these researchers stated that longer follow-up is needed to examine safety and durability.

Secemsky et al (2022) stated that there has been growing use of intra-vascular US (IVUS) during lower extremity arterial and venous re-vascularization.  Observational data suggested that the use of IVUS could improve peri-procedural and long-term outcomes; however, prospective, large-scale data remain limited.  Consensus opinion regarding the appropriate use of IVUS during peripheral intervention is needed.  In a consensus document, these investigators provided guidance on the appropriate use of IVUS in various phases of peripheral arterial and venous interventions.  A 12-member writing committee was convened to derive consensus regarding the appropriate clinical scenarios for use of peripheral IVUS.  The group iteratively created a 72-question survey representing 12 lower extremity arterial interventional scenarios.  Separately, a 40-question survey representing 8 ilio-femoral venous interventional scenarios was constructed.  Clinical scenarios were categorized by interventional phases: pre-intervention, intra-procedure, and post-intervention optimization.  A total of 30 international vascular experts (15 for each survey) anonymously completed the survey instrument.  Results were categorized by appropriateness using the median value and disseminated to the voting panel to re-evaluate for any disagreement.  Consensus opinion concluded that IVUS use may be appropriate during the pre-intervention phase for evaluating the etiology of vessel occlusion and plaque morphology in the iliac and femoro-popliteal arteries.  IVUS was otherwise rated as appropriate during iliac and femoro-popliteal re-vascularization in most other pre-intervention scenarios, as well as intra-procedural and post-procedural optimization phases.  IVUS was rated appropriate in all interventional phases for the tibial arteries.  For ilio-femoral venous interventions, IVUS was rated as appropriate in all interventional phases.  The authors concluded that expert consensus could aid in defining clinical procedural scenarios in which peripheral IVUS may have value during lower extremity arterial and venous intervention while additional prospective data are collected.

Aspiration of a Plunging Ranula in the Submandibular Region

George et al (2015) stated that congenital ranulas seldom occur, with bilateral presentation and prenatal diagnosis reported very rarely.  These investigators believed this was the 1st reported case of a neonate with an antenatally diagnosed massive congenital ranula, who went on to develop a non-contiguous contralateral ranula, both contributing to obstruction in a complex pediatric airway.  A female neonate was born to a non-primigravid mother via a planned elective caesarean section due to a lower facial defect and oral cyst.  Antenatal aspiration of the pseudocyst was carried out under ultrasound guidance with limited success.  In the immediate post-natal period, a poor airway was observed, and the cyst was subsequently marsupialized.  With the development of macroglossia secondary to oedema and tongue base collapse the airway was secured through surgical tracheostomy. A subsequent ultrasound scan revealed the presence of a second solitary cystic mass on the contralateral side.  After careful excision of the contralateral pseudocyst, tongue function improved, with the resolution of a safe airway which permitted successful decannulation.  A planned definitive procedure antenatally did not result in the anticipated improvement in function; however, the subsequent development of a 2nd non-contiguous pseudocyst and further surgical management resulted in a safe airway, improved masticator function and the ability to thrive.  The authors concluded that the pre-natal diagnosis of congenital ranulas have been seldom reported, with no reported cases of contralateral occurrence and airway obstruction from an intra-oral ranula.  These researchers stated that this rare case highlighted the need for a well-considered contingency plan when surgery is needed for a neonatal airway at risk.

Aspiration/Injection of Shoulder Ganglion Cyst/Hematoma

Chiou et al (1999) examined the therapeutic effect of ultrasound (US)-guided aspiration of a ganglion cyst of the shoulder.  A total of 15 patients (9 male and, 6 female) with chronic shoulder pain were enrolled in this study.  Each patient was referred to rule out rotator cuff lesion.  The US examination showed an anechoic cystic lesion in the shoulder region in every patient and abnormality of the rotator cuff in only 4 patients.  Under US, an 18-G needle was inserted into the cyst to aspirate the fluid.  Initial sonographic imaging showed the cyst, which appeared as a localized fluid accumulation and was located between the deltoid muscle and the subscapularis tendon in 7 patients, between the deltoid muscle and the biceps tendon in 1 patient, below the coracoacromial ligament in 5 patients, and over suprascapular notch area in 1 patient.  The ganglion cysts ranged in size from 3.5 to 30 mm.  The amount of aspirated fluid in each cyst varied from 0.4 to 12 ml (mean of 2.6 ml +/- 3.1) with a clear or light yellowish color and a jelly-like appearance.  No major complications occurred during or after this procedure.  The symptom (pain) was improved after US-guided aspiration in each patient.  Follow-up study showed complete relief of pain in 4 patients, marked improvement in 9 patients, and mild improvement but still persistent shoulder pain in 2 patients.  Duration of follow-up study ranged from 2 to 24 months (mean of 6.4 months +/- 6.9).  The success rate for US-guided aspiration was 86 % based on marked symptom improvement or relief.  The authors concluded that US-guided aspiration of shoulder ganglion cysts was an effective procedure in the management of shoulder pain caused by ganglion cysts.  This was a small study (n = 15); with relatively short-term following up (2 to 24 months; 11 of them were 2 to 6 months); these preliminary findings need to be validated by well-designed studies.

Botulinum Toxin Injection for the Treatment of Cervical Dystonia

Hong et al (2012) noted that dysphagia is a common side effect after botulinum toxin (BTX) injections for cervical dystonia (CD), with an incidence of 10 to 40 %, depending upon the study and dose used.  This study consisted of 5 pre-selected women who met criteria for CD and subsequent dysphagia after electromyography (EMG)-guided injections.  Injections were performed with US imaging, and the effects on swallowing were examined.  Separately, sternocleidomastoid (SCM) thickness in healthy controls and treated patients was measured.  There were 34 episodes of dysphagia over 98 injection sessions using EMG guidance for a cumulative rate of 34.7 %.  Using US plus EMG guidance, there was 0 % dysphagia across 27 injection sessions; SCM thickness was less than 1.1 cm.  The authors concluded that US combined with EMG guidance eliminated recurrent dysphagia after BTX treatment, possibly by keeping the injectate within the SCM.

Huang et al (2015) examined the efficacy of US-guided local injection of BTX type A (BTX-A) treatment with orthopedic joint brace in patients with CD.  A total of 105 patients with CD were selected and randomly divided into medication treatment group (A group), BTX treatment group under US guidance (B group) and BTX under US guidance combined with orthopedic joint brace treatment group (C group).  Tsui scale and Spitzer quality of life (QOL) index was used to evaluate the spasm and QOL.  The scores of Tsui scale and Spitzer QOL index were compared after US-guided local treatment for 1 month, 3 months and 6 months.  The difference in Tsui and Spitzer scores before and after the treatment of oral medications were not statistically significant (p > 0.05).  Whereas, the differences in Tsui and Spitzer scores before and after the treatment between local injection of BTX-A treatment group and orthopedic joint brace combined with BTX-A injection group were statistically significant (p < 0.05).  Furthermore, the difference in Tsui and Spitzer scores of orthopedic joint brace combined with BTX-A injection group at 3 months, and 6 months were statistically significant compared to local injection of BTX-A treatment group (p < 0.05).  The authors concluded that US-guided local injection of BTX-A combined with orthopedic brace could significantly reduce muscle tension and improve QOL.  Moreover, US-guidance helped reduce BTX injection amount without affecting the efficacy and ensured that the medicine accurately reached to the site of action with a lower occurrence rate of adverse reactions.

In a systematic review, Grigoriu et al (2015) examined the impact of different injection-guiding techniques on the effectiveness of BTX-A for the treatment of focal spasticity and dystonia.  Data sources included Medline via PubMed, Academic Search Premier, PASCAL, the Cochrane Library, Scopus, SpringerLink, Web of Science, EM Premium, and PsycINFO; 2 reviewers independently selected studies based on pre-determined inclusion criteria.  Data relating to the aim were extracted.  Methodological quality was graded independently by 2 reviewers using the Physiotherapy Evidence Database assessment scale for randomized controlled trials (RCTs) and the Downs and Black evaluation tool for non-RCTs.  Level of evidence was determined using the modified Sackett scale.  A total of 10 studies were included; 7 were randomized.  There was strong evidence (level 1) that instrumented guiding (US, electrical stimulation [ES], EMG) was more effective than manual needle placement for the treatment of spasmodic torticollis, upper limb spasticity, and spastic equinus in patients with stroke, and spastic equinus in children with cerebral palsy (CP); 3 studies provided strong evidence (level 1) of similar effectiveness of US and ES for upper and lower limb spasticity in patients with stroke, and spastic equinus in children with CP, but there was poor evidence or no available evidence for EMG or other instrumented techniques.  The authors concluded that these findings strongly recommended instrumented guidance of BTX-A injection for the treatment of spasticity in adults and children (ES or US), and of focal dystonia such as spasmodic torticollis (EMG).  No specific recommendations can be made regarding the choice of instrumented guiding technique, except that US appeared to be more effective than ES for spastic equinus in adults with stroke.

Allison and Odderson (2016) reported a case of a young man with idiopathic CD who developed anterocollis (forward flexion of the neck) not responsive to prior scalene and SCM injections.  To safely access the deeper cervical musculature, US was used in conjunction with EMG, to inject the longus colli muscles bilaterally.  The patient responded well and had no complications.  The longus colli has been reported to be injected using EMG, fluoroscopy, computed tomography (CT), and, less frequently, US.  The authors proposed that US guidance is an excellent technique for BTX injection, especially for deep cervical muscles such as the longus colli.

Kutschenko et al (2020) examined the correlations of BTX therapy with dysphagia.  These researchers studied a group of CD patients with optimized BTX therapy during a prolonged period of time to record their dysphagia frequency, severity and duration; they also assessed potential risk factors and attempted to avoid it by using US guidance for BTX applications.  BTX therapy of 75 CD patients (23 men, 52 women, age of 60 ± 12 years, BTX total dose of 303.5 ± 101.5 uMU) was retrospectively analyzed for 1 year.  BTX therapy was optimized before the observation period.  Dysphagia was noticed by 1/5 of the patients.  In those patients, it only occurred in about 1/3 of the injection series.  It was never associated with a functional deficit and lasted several days to 2 weeks.  It was not related to patient age or gender, BTX total dose, BTX dose in the SCM, BTX dose in the SCM and scalenii muscles, by BX  therapy with bilateral SCM injections or BTX therapy with abobotulinumtoxinA.  The authors concluded that US guidance was not able to prevent it.  These researchers stated that further prospective studies are needed to examine the underlying dystonia associated swallowing abnormalities as a potentially predisposing factor.

Kim et al (2021) stated that US guidance may improve the accuracy of BTX injection, but studies of its potential for CD treatment are lacking.  In an observational study, these researchers determined the accuracy of US-guided injection in the SCM; a total of 18 embalmed cadavers were used in this study.  In total, 36 SCMs from 18 embalmed cadavers were examined.  One physician performed US scans to divide each SCM into quarters and evaluated its cross-sectional area (CSA) and thickness at each of 3 meeting points between adjacent quarters.  Under US guidance, another experienced physician injected methylene blue solution at 1 of the 3 points, using the in-plane technique (12 specimens/point; right SCM 3 ml, left SCM 5 ml).  One anatomist dissected all cadavers and measured the distance of dye dispersion along the longitudinal axis of each muscle.  Dispersion ratio was calculated as longitudinal dye dispersion divided by SCM length.  Main outcome measures were SCM thickness and CSA; dye dispersion patterns (dispersion distance and dispersion ratio).  SCM thickness and CSA were greatest at the middle injection point (mean ± SD 6.6 ± 2.0 mm and 1.4 ± 0.6 cm2 , respectively).  All injections were successful, except in 1 case where the SCM was thin and the dye reached the omohyoid muscle.  Mean longitudinal dye dispersion and dispersion ratio were significantly greater when the volume was 5 ml.  There were no statistically significant differences in dispersion patterns among the 3 injection points.  The authors concluded that US-guided intra-muscular injection could be performed with good accuracy in the SCM, as US could be used to evaluate SCM thickness and CSA.  Moreover, these researchers stated that higher volumes of injection solution appeared to diffuse better, but further clinical studies are needed to determine optimal injection volume.

Furthermore, an UpToDate review on "Treatment of dystonia" (Comella, 2020) states that "there is no consensus regarding standard practices for BoNT injections, including dilution ratios for the different BoNT products, the dose per injection, the total dose per muscle, the number of injections at each site, or the methods of targeting injections (e.g., whether guided by vision, electromyography, or ultrasound).  All of these parameters vary among practitioners and centers".

Botulinum Toxin Injection for the Treatment of Limb and Paraspinal Spasticity

In a prospective study, Py et al (2009) examined the effectiveness of injecting botulinum toxin A (BTX-A) into the lower limbs of children with CP, according to age, dose, dilution, injection site and needle placement technique (manual or US guidance).  Any child with CP examined between May 2005 and May 2006 who needed BTX-A injections in the adductor, hamstring, gastrocnemius and/or soleus muscles could be included.  A total of 54 children participated in the study, 30 of whom were injected under US guidance.  The pre- and post-toxin evaluations were carried out through analytical clinical examination and the Gross Motor Function Measure (GMFM-88).  These researchers found an overall clinical effectiveness for 51 % of the children.  This effectiveness was significantly higher for children under 6 years old or over 12, especially when the doses were greater than 0.8 UI/kg per muscle of BTX, when the injected muscles were hamstrings or gastrocnemius, and when the injections were guided by US.  Dilution had no effect on clinical effectiveness.  Function after 1 month was better for 24 % of the children.  This functional improvement was significantly better for children under 6 years old with the injections under US control.  The authors concluded that the findings of this study confirmed that the effectiveness of BTX injections was higher in younger children, with injected doses higher than 0.8 UI/kg per muscle of BTX injections guided by US.  These preliminary findings need to be validated by well-designed studies. 

The authors stated that the main drawback of this study was that it was not a double-blind trial, which made interpreting the results less reliable.  Also, the post-toxin evaluation took place before 1 month had passed also probably limited the significance of the results, as did the injection of low doses of the BTX per muscle for multi-site injections, in order to respect the cumulative dose of 6 UI/kg of Botox.  Because both a radiologist and a re-education specialist need to be available at the same time, the muscle groups that would benefit the most from this technique (e.g., deep muscles? thin muscles?) need to be defined in order to use these specialists’ time more efficiently.  This research should be continued with more sensitive methods for evaluating effectiveness and higher doses of BTX.

Rha et al (2014) stated that although the tibialis posterior is a potentially difficult muscle to locate for BTX injection because of its deep location, needle insertion is usually carried out using anatomic landmarks for guidance.  Accordingly, the ultrasonographic anatomy of the lower leg was examined in hemiplegic children with spastic CP to improve the safety and the accuracy of needle placement into the tibialis posterior.  A total of 25 subjects (2 years 2 months to 5 years 11 months; 12 boys, 13 girls; Gross Motor Function Classification System levels I to II) were recruited.  B-mode, real-time US was carried out using a 5- to 12-MHz linear array transducer.  During anterior and posterior approaches, safety window width (tibia to the neurovascular bundle) and depth (skin to the mid-point of the tibialis posterior) were measured at the upper third and at the mid-point of the tibia.  For the anterior approach, the safety window width at the upper third of the tibia (mean [SD] of 0.63 [0.12] cm, range of 0.44 to 0.93 cm) was significantly larger than that at the mid-point (0.38 [0.09] cm, range from 0.22 to 0.59 cm, p < 0.05) of the affected leg.  However, for the posterior approach, the safety window width at the mid-point (0.74 [0.23] cm, range from 0.21 to 1.18 cm) was significantly larger than that at the upper third of the tibia (0.48 [0.23] cm, range from 0.10 to 0.97 cm, p < 0.05) on the affected leg.  The authors concluded that US guidance was a useful, safe, and accurate tool for needle insertion into the tibialis posterior.  These investigators noted that considering the safety window width, the findings of this study suggested needle placement at the upper third point of the tibia for the anterior approach and at the mid-point for the posterior approach.

Wong et al (2015) noted that injections with BTX have been used off-label in treating cerebral palsy scoliosis (CPS).  In a prospective, randomized, triple-blinded, cross-over study, these researchers reported both radiological and clinical improvement, whereas showing no side effects or complications in patients treated with either BTX-A or saline (NaCl).  Subjects (brace-treated CPS between 2 and 18 years of age) were injected using US-guidance with either NaCl or BTX in selected spine muscles with 6 months intervals (block randomization, sealed envelope).  Radiographs of the spine and clinical follow-up were captured before and 6 weeks after each injection.  Primary outcome parameter was radiological change in Cobb angle, where a 7° change was regarded as an effect (1 SD).  Radiological parameters were measured before and 6 weeks after treatment by 3 experienced doctors separately.  Moreover, clinical results were evaluated by the pediatric quality of life score and systematic open questioning of the parents about the child's wellbeing.  Subjects, researchers, and monitors were blinded during the trial.  A total of 16 CP patients (GFMCS III-V) with CPS were consecutively included, whereas 6 patients were excluded.  There were no drop-outs to follow-up, but 1 possible serious AE of pneumonia resulting in death was recorded and the study was terminated.  No significant radiological or clinical changes were detected when compared with NaCl injections using Wilcoxon matched pair signed-rank test.  The authors concluded that no positive radiological or clinical effects were demonstrated by this treatment, except for the parent's initial subjective but positive appraisal of the effect; however, the study was terminated due to 1 possible severe AE and scheduled numbers needed to treat (hence power) were not reached.

Schwabe (2016) stated that botulinum neurotoxin (BoNT) is one of the mainstays in the treatment of pediatric spasticity and dystonia.  When considering initiation of BoNT treatment for spasticity, treatment goals and responses to prior conservative measures such as passive ROM exercises, splinting, and other medication trials should be reviewed.  As a general rule, children should be engaged in therapy services around the time of the injections and have a robust home program in place.  When managing spasticity in children with BoNT injections, the practitioner should be well versed in functional anatomy with specialized training in injection techniques.  Localization techniques in addition to anatomical landmarks are recommended for improved efficacy and include limited EMG, electrical stimulation (ES), and/or US guidance.  A follow-up visit for the purpose of re-assessment during the peak effect of the drug is advised.  It is known that BoNT is effective at reducing spasticity and improving ROM, but it remains to be determined to what degree this translated into improved function, activity, and participation.

Botulinum Toxin Injection of Scalene and Pectoralis Muscles for the treatment of Spasmodic Torticollis

Walter and Dressler (2014) stated that botulinum toxin (BTX) therapy is used in neurology to treat muscle hyperactivity disorders including dystonia, spasticity, CP, hemi-facial spasms and re-innervation synkinesias as well as exocrine gland hyperactivity disorders.  To increase its therapeutic effect and to decrease adverse effects in adjacent tissues, exact BTX placement is important; US allows non-invasive, real-time imaging of muscular and glandular tissues and their surrounding structures.  It can visualize, guide, and standardize the entire procedure of BTX application.  Small, randomized studies suggested that US-guidance can improve effectiveness and reduce adverse effects of BTX therapy when compared to conventional placement.  US-guidance should be used in forearm muscles when functionality is important, and in selected leg muscles.  It may be used for targeting distinct neck muscles in cervical dystonia.  It is helpful for targeting the salivary glands.  Moreover, these researchers stated that large-scale studies comparing US with other techniques for guidance of BTX application are needed.

The American Academy of Neurology (AAN)’s practice guideline on “Botulinum neurotoxin for the treatment of blepharospasm, cervical dystonia, adult spasticity, and headache” (Simpson et al, 2016) noted that 1 Class II study compared 3 different techniques for guiding BoNT injection placement (manual needle placement, electrical stimulation, and US) and did not find consistent outcomes favoring one technique.  It concluded that there is insufficient evidence to support or refute the superiority of specific techniques for guiding botulinum toxin injection placement (inconsistent outcomes from 1 Class II study).

Calcaneal / Retrocalcaneal Bursa Injection

Brophy et al (1995) described the use of ultrasound (US) guidance for local steroid injection of the retrocalcaneal bursa and the tibialis posterior tendon sheath in patients with chronic inflammatory arthropathy.  The authors concluded that US guidance may be the injection technique of choice but is especially indicated for patients with lesions unresponsive to injections guided by palpation.

Boesen et al (2006) described a case report of a 62-year old man with a 20-year history of tendon problems, who presented with a swollen and tender left Achilles tendon; US revealed a 2 x 1 x 0.9 cm intra-tendinous substance with acoustic shadowing.  On a radiogram, ossification was found.  Color Doppler activity was present in both the bursa and the tendon.  A US-guided injection of 40-mg Depomedrol was applied into the retrocalcaneal bursa.  On follow-up 2 months later, the patient had no symptoms and US showed total regression of Doppler activity.  The ossification was unchanged.  The authors concluded that US color Doppler may be recommended for guidance and monitoring of treatment.

Goldberg-Stein et al (2016) described a lateral fluoroscopically-guided retrocalcaneal bursa injection technique, reported patient outcomes at 1 to 4 weeks after steroid/anesthetic retrocalcaneal bursal therapeutic injection, and correlated pre-injection diagnostic heel US variables with improvement in patient pain scores.  After internal review board (IRB) approval, fluoroscopically guided therapeutic retrocalcaneal bursa injections performed using a lateral approach were retrospectively reviewed.  Pre-injection heel US results and pre- and post-injection patient visual analog scale (VAS) pain scores (scale 0 to 10) were recorded.  The Wilcox matched-pair test compared pain scores, and Spearman's rho assessed for correlation between pain score changes and heel US results.  A total of 32 injections were performed in 30 patients (25 females, 5 males; mean of 56.5 ± 9.3 years, range of 39 to 75 years; 21 left heels, 11 right heels) with technical success in 32 of 32 cases (100 %).  Insertional Achilles tendon pathology and retrocalcaneal bursitis were present in 31 of 32 cases (97 %) and 16 of 32 cases (50 %), respectively. Median pre- and post-procedure pain scores were 8 (IQR 7, 10) and 1.75 (IQR 0, 6). A statistically significant decrease in pain score was observed following injection, with a median change of 4.75 (inter-quartile range [IQR] 3, 8; p < 0.001).  Clinically significant response (greater than 50 % reduction in pain score) was present in 69 % (95 % confidence interval [CI]: 0.52 to 0.86; p < 0.001).  No significant correlation was identified between a decrease in pain score and a sonographically abnormal Achilles tendon or retrocalcaneal bursa.  The authors concluded that fluoroscopically-guided retrocalcaneal bursal steroid/anesthetic using a lateral approach was an effective technique.  This technique yielded 100 % technical success and a clinically significant decrease in patient pain scores (p < 0.001).

An UpToDate review on “Bursitis: An overview of clinical manifestations, diagnosis, and management” (Todd, 2021) states that “Among patients with bursitis, obvious signs of swelling and inflammation may be evident upon physical exam only in superficial processes, such as olecranon, prepatellar, infrapatellar, or retrocalcaneal bursitis … we do not recommend the use of intralesional glucocorticoids in the treatment of the superficial forms of bursitis (olecranon, prepatellar, and retrocalcaneal) due to the risk of infectious complications, local tendon injury, draining sinus tract, or overlying skin atrophy … ”.

Furthermore, an UpToDate review on “Plantar fasciitis” (Buchbinder, 2021) states that “Overall, the diagnostic utility of ultrasound for plantar fasciitis is unproven as it may not add value over a clinical diagnosis and is not recommended for routine use … There is moderate-quality evidence that use of ultrasound to guide placement of the injection does not improve pain more than palpation-guided injections”.

Calcified Medial Collateral Ligament Injection

An UpToDate review on “Medial collateral ligament injury of the knee” (Dexter, 2022) does not mention the use of ultrasound guidance as a management / therapeutic tool.

Carpometacarpal (CMC) Joint Injection

To et al (2017) examined the accuracy of hand injections with and without the aid of US into the carpal tunnel, thumb carpometacarpal (CMC) joint, 1st dorsal compartment (DC) and the radiocarpal (RC) joint.  A total of 4 participants of various level of experience injected the carpal tunnel, thumb CMC, 1st DC, and RC joint into 40 fresh frozen cadaver specimens with blue dye and radiographic contrast.  Participants 1 and 2 were injected without US guidance, and participants 3 and 4 were injected with US guidance.  A successful injection was determined by both fluoroscopy and dissection/direct observation.  Additional information was recorded for each injection such as median nerve infiltration and evidence of thumb CMC arthrosis.  The overall accuracy for carpal tunnel, thumb CMC, 1st DC, and RC injections were 95 %, 63 %, 90 %, and 90 %, respectively.  Success was compared with and without US guidance.  Success rates were similar for each injection site, except the thumb CMC joint, where US participants had 25 % higher accuracy.  In the setting of thumb CMC arthrosis, the incidence of success was 38 % for participants with no US aid and 72 % for participants with US aid.  There was a significant difference between participants who used US with the participant with more US experience being more successful.  The authors concluded that carpal tunnel, 1st DC, and RC injections had an accuracy of greater than 90 %.  Thumb CMC injections had a lower accuracy (63 %) and one can improve accuracy with US.  The accuracy of US-guided injections is dependent on the user and their experience.

The authors stated that this study had several drawbacks.  First, these researchers used fresh frozen cadavers; therefore, no clinical conclusion could be made.  Second, the number of cadavers used (n = 40) was limited due to expense and was insufficient to perform a power analysis.  Third, the study design that could be inferred would be the inclusion of the physician assistant.  These investigators felt it was important to have a participant who was a non-surgeon.

In a pilot study, Derian et al (2018) examined the accuracy of US guidance compared to palpation in performing CMC joint injections in cadavers.  A total of 36 CMC joints were randomized to either US-guided or palpation-based injections, with 1-cc of blue latex solution injected into each joint.  The specimens were then dissected; and the distribution of the latex was assessed by 2 independent, blinded raters.  Injection accuracy was evaluated on a 4-point quartile rating scale of 1 to 4, corresponding to the amount of the latex solution within the joint (1 = 0 to 25 %, 2 = 26 to 50 %, 3 = 51 to 75 %, 4 = 76 to 100 %).  Inter-rater reliability was a secondary measure.  The mean rating of accuracy was 2.1 for both palpation-based and US-guided injections.  There was no statistically significant difference in accuracy between the 2 injectors.  Chi-square analysis testing differences in accuracy for the 2 conditions was not statistically significant.  The Cronbach's alpha for rater 2 was 0.74, which represents an acceptable level of reliability.  A Friedman's Chi-square for the 2 raters was 2.3 (p = 0.13), indicating no significant difference between raters.  The authors concluded that US guidance did not improve the accuracy of CMC joint injections in cadavers; however, the high inter-rater reliability attested to the value of the novel assessment scale.

The authors stated that this study had several drawbacks, including a small sample size (n = 36 CMC joints), the visual estimation involved in the rating scale used to evaluate accuracy, and the limited potential for extrapolation of outcomes to a clinical model.  A smaller US probe may have been a more appropriate choice for CMC injections.  A total of 48 joints were available for injection, of which 36 were injected and evaluated for the purposes of this study.  Raters did not have any formal training in the evaluation of injection accuracy, relying solely on their professional experience in their respective fields of anatomy and physiatry.  Despite this, there was strong inter-rater reliability, with no statistically significant differences between the accuracy ratings.  The method of gauging accuracy was based on a novel assessment scale that has not been previously validated.  Quartiles were measured visually without any standardized quantification.  The arthritic CMC joints may not have been able to contain 1 cc of latex solution; therefore, resulting in extravasation.  In lieu of no radiographic assessment and no information on age of the cadaver to elucidate likelihood of arthritic changes in 1st CMC, this might have resulted in “inaccuracy” when the needle tip was in fact correctly placed . It may not have been appropriate to initially test this novel assessment scale in small joint models.  The difference between 25 % and 30 % accuracy would probably be easier to assess in a large joint rather than a small one.

Clavi-Pectoral Fascial Plane Block

Kukreja et al (2020) noted that the clavipectoral fascial plane block (CPB) is a novel regional anesthesia technique that has been used for clavicular fracture surgery.  While the cutaneous innervation of the skin above the clavicle is well-known to be supplied by the supra-clavicular nerve of the superficial cervical plexus (SCP), the sensory innervation of the clavicle itself is somewhat controversial.  Despite this controversy, it has been hypothesized that the CPB is an effective regional anesthesia technique for peri-operative analgesia since the terminal branches of many of the sensory nerves like suprascapular, subclavian, lateral pectoral, and long thoracic nerves pass through the plane between the clavipectoral fascia and the clavicle itself.  These researchers presented the findings of 3 patients on the safety and effectiveness of CPB .  Moreover, they noted that the decision to use the CPB alone or in addition to other techniques (SCP or interscalene block) may depend on the site of clavicle injury or variations in clavicular innervation.  These investigators stated that larger, prospective studies are needed to further clarify the distribution of sensory blockade and the efficacy and safety of the CPB.  Furthermore, they stated that until the controversy regarding sensory innervation of the clavicle is addressed or randomized controlled trials comparing SCP and brachial plexus blocks in clavicle surgery are carried out, a consensus on the regional anesthetic technique to be used for these surgeries may not be reached.

Costochondral Injection

Cho and Park (2019) stated that Tietze`s syndrome is an uncommon disease of unknown etiology that manifests as pain and tenderness of the para-sternal joints.  To-date, however, there has been no report on US findings concerning swelling of the costochondral joint in Tietze`s syndrome.  Moreover, there has been no research investigating images of US-guided corticosteroid injection, although corticosteroid injection is one of the most important treatments for Tietze`s syndrome.  These investigators reported a case of Tietze`s syndrome where US images were used in the diagnostic and therapeutic process.  A 70-year old man was examined for left chest pain that had lasted for several weeks.  Physical examination at the authors’ clinic revealed a focal tenderness of the left third costochondral joint, and ultrasonography showed a swelling of the left third costochondral joint.  Considering both the clinical and radiological examinations, the patient received a diagnosis of Tietze`s syndrome with costochondral joint swelling.  Then, the patient agreed to an US-guided left third costochondral corticosteroid injection after receiving a detailed explanation of the disease and treatment.  After receiving 3 US-guided corticosteroid injections, his chest pain subsided, and the swelling and tenderness also disappeared completely.  The authors concluded that the findings of this case suggested that US was important in the diagnosis and treatment of Tietze`s syndrome.

Dorsal Scapular Nerve Block

Harmon and Hearty (2007) described a case report of using real-time, high-resolution ultrasound (US) guidance to facilitate blockade of the suprascapular nerve (SSN).  They described a case report and technique for using a portable US scanner (38 mm broadband (13-6 MHz) linear array transducer (SonoSite Micromaxx SonoSite, Inc.) to guide SSN block.  The subject was a 44-year old man who presented with severe, painful osteoarthritis with adhesive capsulitis of his right shoulder.  The US transducer in a transverse orientation was placed over the scapular spine.  Moving the transducer cephalad the suprascapular fossa was identified.  While imaging the supraspinatus muscle and the bony fossa underneath, the US transducer was moved laterally (maintaining a transverse transducer orientation) to locate the suprascapular notch.  The SSN was seen as a round hyperechoic structure at 4-cm depth beneath the transverse scapular ligament in the scapular notch.  The nerve had an approximate diameter of 200 mm.  Real-time imaging was used to direct injection in the scapular notch; US scanning confirmed local anesthetic spread.  The patient's pain intensity decreased; shoulder movement and function improved.  These improvements were maintained at 12 weeks.  The authors concluded that US guidance did not expose patients and personnel to radiation.  It was also less expensive than other imaging modalities.  This technique has applications in both acute and chronic pain management.

Borglum et al (2011) presented a case with an US-guided (USG) placement of a perineural catheter beneath the transverse scapular ligament in the scapular notch to provide a continuous block of the SSN.  The patient suffered from a severe and very painful adhesive capsulitis of the left shoulder secondary to an operation in the same shoulder conducted 20 weeks previously for impingement syndrome and a superior labral anterior-posterior tear.  Following a new operation with capsular release, the placement of a continuous nerve block catheter subsequently allowed for nearly pain-free low impact passive and guided active mobilization by the performing physiotherapist for 3 consecutive weeks.  This case and a short topical review on the use of SSN block in painful shoulder conditions highlighted the possibility of a USG continuous nerve block of the SSN as sufficient pain management in the immediate post-operative period following capsular release of the shoulder.  Findings in other painful shoulder conditions and suggestions for future studies were discussed in the text.

Laumonerie et al (2019a) noted that a bone landmark-based approach (LBA) to the distal SSN (dSSN) block is an attractive "low-tech" method available to physicians with no advanced training in regional anesthesia or US guidance.  The primary aim of this study was to validate the feasibility of an LBA to blockade of the dSSN by orthopedic surgeons using anatomic analysis.  The secondary aim was to describe the anatomic features of the sensory branches of the dSSN.  An LBA was performed in 15 cadaver shoulders by an orthopedic resident.  Then, 10 ml of methylene blue-infused 0.75 % ropivacaine was injected around the dSSN; 2.5ml of red latex solution was also injected to identify the position of the needle tip.  The division and distribution of the sensory branches that originate from the SSN were described.  The median distance between the dSSN and the site of injection was 1.5 cm (0 to 4.5 cm).  The most common injection site was at the proximal third of the scapular neck (n = 8); 15 dSSNs were stained proximal to the origin of the most proximal sensory branch.  All 15 dSSNs gave off 3 sensory branches that innervated the posterior glenohumeral capsule, the subacromial bursa, and the coraco-clavicular and acromio-clavicular ligaments.  The authors concluded that an LBA for anesthetic blockade of the dSSN by an orthopedic surgeon was a simple, reliable, and accurate method.  Injection close to the suprascapular notch was recommended to involve the dSSN proximally and its 3 sensory branches.

Laumonerie et al (2019b) compared the accuracy of dSSN blockade performed with the use of US-guided regional anesthesia (USRA) versus with a LBA.  A secondary aim was to describe the anatomic features of the sensory branches of the dSSN.  USRA and LBA were performed in 15 shoulders each from 15 cadavers (total of 30 shoulders).  Then, 10-ml of methylene blue-infused ropivacaine 0.75 % was injected into the dSSN.  Simultaneously, 2.5-ml red latex solution was injected to identify the position of the needle tip.  The division and distribution of the sensory branches originating from the SSN were described.  The tip of the needle was identified at 1.3 cm (range of  0 to 5.2 cm) and 1.5 cm (range of 0 to 4.5 cm) with USRA and the LBA, respectively (p = 0.90).  Staining diffused past the origin of the most proximal sensory branch in 27 cases.  The most proximal sensory branch arose 2.5 cm from the suprascapular notch.  Among the 3 failures that occurred in the USRA group, the sensory branches also failed to be marked.  All 30 dSSNs gave off 3 sensory branches, which innervated the posterior glenohumeral capsule, the subacromial bursa, and the coraco-clavicular and acromio-clavicular ligaments.  An LBA was as reliable and accurate as USG for anesthetic blockade of the dSSN.  Marking of the SSN must be proximal to the suprascapular notch to involve the 3 sensory branches in the anesthetic blockade.  The authors concluded that the present study demonstrated that a LBA to anesthetic blockade of the dSSN was accurate and can be performed by orthopedic surgeons lacking experience in USG anesthetic techniques.

Foot/Heel Injection for Adventitious Bursitis/Capsulitis

Srivastava and Aggarwal (2016) noted that ultrasound (US)-guided corticosteroid injection has been shown to be safe and effective for varied causes of plantar fasciitis; however, its use for Achilles tendinitis is controversial.   These researchers examined the efficacy and changes in US findings at Achilles enthesitis after corticosteroid injection in patients with spondyloarthropathy (SpA).  Patients with SpA with symptomatic Achilles enthesitis, refractory to 6 weeks of full-dose non-steroidal anti-inflammatory drugs (NSAIDs), were offered US-guided local corticosteroid injection.  Injected entheses were examined by US (both B mode and power Doppler) at baseline and 6 weeks after injection.  Standard OMERACT definitions were used to define enthesitis.  Achilles tendon thickness of greater than 5.29 mm, 2 cm proximal to insertion in long axis, was considered thickened.  A total of 27 symptomatic Achilles tendons (in 18 patients) were injected with 20-mg methylprednisolone under US guidance baseline, and 6-week follow-up US features were compared.  All patients reported improvement in pain (VAS) in the affected tendon after injection (p < 0.0001).  Simultaneously, improvement in local inflammatory changes were noted, in the form of significant reduction in tendon thickness (p < 0.0001), vascularity (p < 0.0001), peritendinous edema (p = 0.001), bursitis and bursal vascularity (p < 0.001 and < 0.0001, respectively).  There was no change in bone erosions and enthesophyte.  None of the patients had tendon rupture or other injection-related complications at 6 weeks of follow-up.  The authors concluded that US-guided local corticosteroid injection was a safe and effective modality for refractory Achilles enthesitis in patients with SpA and led to reversion of acute changes at entheseal site.  This was a small (n = 18 patients) study without a control group and addressed the use of US-guided injection for the treatment of Achilles tendinitis.

Wang et al (2019) stated that posterior heel pain is a common complaint that is often caused by overuse injuries.  In such cases, the retrocalcaneal bursa is compressed and chafed repeatedly, leading to local inflammation.  Sonography is a popular imaging tool used to study the pathology of soft tissues, and it can be used to assist in diagnosing bursitis because of its accuracy.  These investigators reported an innovative method to treat retrocalcaneal bursitis under US guidance.  A total of 10 patients with posterior heel pain for greater than 6 months who failed conservative treatment received this US-guided minimally invasive surgery.  An endoscopic puncher and burr were inserted under US guidance via a stabbing wound, and the swollen retrocalcaneal bursa and bony prominence were resected.  The patients were able to ambulate and undergo a rehabilitation program 2 weeks post-operatively.  In the patients who underwent this US-guided minimally invasive surgery, both the average surgical time and average hospital stay were shorter than in those (n = 12) who underwent open surgery.  In outcome rating assessment, the American Orthopedic Foot & Ankle Society (AOFAS) pain score and total AOFAS ankle-hindfoot score were improved in the US-guided minimally invasive surgery group compared to the open surgery group at 2 months post-operatively.  Other advantages included lesser wound pain, shorter hospital stay, faster recovery time, and minimal blood loss.  The authors concluded that US-guided surgery appeared to be a good option for the treatment of retrocalcaneal bursitis.  This was a small (n = 10 patients) study without a control group and addressed the use of US-guided minimally invasive surgery for the treatment of retrocalcaneal bursitis.

Ganglion Cyst Injection of the Wrist / Wrist Injection

Breidahl and Adler (1996) demonstrated the use of ultrasound (US) guidance in confirming intralesional injection of corticosteroids and local anesthetic into symptomatic ganglia; and proposed potential advantages of this technique.  A total of 10 patients (5 men, 5 women) underwent US-guided injection of a ganglion; 7 ganglia were near the wrist, 1 was adjacent to a finger interphalangeal joint and 2 were adjacent to the talus.  All were injected with a 1:1 mixture of long-acting corticosteroid and local anesthetic, the actual volume being dependent on the size of the ganglion; 3 patients had a 2nd injection 9 to 18 months following the initial injection.  In 4 patients the ganglia resolved completely.  In 5 patients there was significant improvement, with a reduction in size of the ganglion and symptomatic relief.  The authors concluded that US-guided injection insured intralesional deposition of corticosteroids and may provide an alternative to surgery in the management of ganglia.

Sofka et al (2001) examined the use of US guidance for intervention in the musculoskeletal system.  All interventional musculoskeletal procedures using US guidance performed at the authors’ institution from July 1998 through November 1999 were reviewed.  Examinations were performed using either a linear or curved phased array transducer, based on depth and local geometry.  The choice of needle was likewise optimized for specific anatomic conditions.  A total of 195 procedures were performed on 167 patients from July 1998 through November 1999; 31 procedures had magnetic resonance (MR) correlation within 6 months beforehand.  Excluding large-joint aspirations and injections, these researchers found that 180 of the procedures were more readily performed using US than any other imaging modality.  These included therapeutic injections into tendon sheaths (biceps, flexor digitorum longus, posterior tibial, and iliopsoas), Morton's neuromas, plantar fascia, wrist ganglia, and tarsal tunnel cysts; peritendinous hamstring injections; and synovial cyst and muscle biopsies.  In all cases, the target of interest was identified easily with US, and needle position was documented readily.  Also in all cases, aspiration or medication delivery to the site of interest was observed during real time and was documented on post-procedure images of the area.  No significant complications (e.g., bleeding, infection, and neurovascular compromise) were encountered during or immediately after any procedure.  The authors concluded that US is a readily available imaging modality useful for guiding interventional procedures in the musculoskeletal system.  The ability to document exact needle placement in real time confirmed accurate placement of therapeutic injections, fluid aspiration, and soft tissue biopsies. Moreover, these researchers stated that although a formal clinical outcome study has yet to be performed, verbal communication with referring clinicians and patients has indicated an overall positive response.

In a retrospective study, Chen et al (2011) described the results of US examination in a series of patients with chronic wrist pain and defined the proportion of occult carpal ganglion in these patients.  This trial included 57 patients with wrist pain consecutively referred for sonographic examination.  The inclusion criteria for this study were a history of wrist pain longer than 3 months with no wrist trauma, and no palpable mass at the wrist.  Ultrasound examination with a 10-MHz linear transducer was used to detect wrist pathology.  A well-demarcated anechoic mass with posterior enhancement and without vascularity within the mass on sonography was defined as a ganglion cyst.  A total of 33 of the 57 patients (58 %) were diagnosed by sonographic examination as having a ganglion in the wrist joint.  The size of the ganglion demonstrated on sonographic imaging ranged from 2 x 5 mm to 10 x 9 mm on a longitudinal scan of the wrist (with a mean of 4 x 7 mm.).  Surgical excision was performed in 12 patients who had ganglions diagnosed by sonographic examination; in all cases, the mucin content of the specimen was demonstrated; 8 patients underwent local aspiration followed by steroid injection under US guidance.  The aspirated content was a jelly-like substance.  In these 20 treated patients, symptoms of wrist pain improved after intervention.  The authors concluded that the prevalence of occult carpal ganglion is common in chronic wrist pain patients; and high-resolution US examination facilitates early detection of occult carpal ganglion.

Smith et al (2011a) compared the accuracies of US-guided and palpation-guided scapho-trapezio-trapezoid (STT) joint injections in a cadaveric model.  A clinician with 6 years of experience performing US-guided procedures injected 1.0 ml of a diluted latex solution into the STT joints of 20 un-embalmed cadaveric wrist specimens using a palmar approach.  At a minimum of 24 hours after injection, an experienced clinician specializing in hand care completed palpation-guided injections in the same specimens using a dorsal approach and 1 ml of a different-colored latex.  A fellowship-trained hand surgeon blinded to the injection technique then dissected each specimen to examine injection accuracy.  Injections were graded as accurate if the colored latex was found in the STT joint, whereas inaccurate injections resulted in no latex being found in the joint.  All US-guided injections were accurate (100 %; 95 % confidence interval [CI]: 81 % to 100 %), whereas only 80 % of palpation-guided injections were accurate (95 % CI: 61 % to 99 %); US-guided injections were significantly more accurate than palpation-guided injections, as determined by the ability to deliver latex into the joint (p < 0.05).  The authors concluded that US guidance can be used to inject the STT joint with a high degree of accuracy and was more accurate than palpation guidance within the limits of this study design.  Clinicians should consider using US guidance to carry out STT joint injections when precise intra-articular placement is needed.  Moreover, these researchers stated that further clinical investigation examining the role of US-guided STT joint injections in the treatment of patients with radial wrist pain syndromes is needed.

Smith et al (2011b) stated that distal radioulnar joint (DRUJ) disorders are uncommon but important causes of ulnar-sided wrist pain and disability.  Fluoroscopically-guided injections may be performed to diagnose or treat DRUJ-related pain or as part of a diagnostic arthrogram.  Sonographic guidance may provide a favorable alternative to fluoroscopic guidance for distal DRUJ injections.  These investigators described and validated a US-guided technique for DRUJ injections in an un-embalmed cadaveric model.  An experienced clinician used US guidance to inject diluted colored latex into the DRUJs of 10 un-embalmed cadaveric specimens.  Subsequent dissection by a fellowship-trained hand surgeon confirmed accurate injections in all 10 specimens; 2 cases of ulnocarpal flow, indicative of triangular fibrocartilage injury, were noted during injection and subsequently confirmed during dissection.  The authors concluded that clinicians should consider using US guidance to perform DRUJ injections when clinically indicated.  Moreover, these researchers stated that further research should examine the efficacy of US-guided DRUJ injections to treat patients with painful DRUJ syndromes or to evaluate the triangular fibrocartilage complex in patients with ulnar wrist pain syndromes.

Laurell et al (2012) noted that the wrist region is one of the most complex joints of the human body.  It is prone to deformity and functional impairment in juvenile idiopathic arthritis (JIA), and is difficult to examine clinically.  These researchers evaluated the role of Doppler US in diagnosis of synovitis, guidance of steroid injections, and follow-up examinations of the wrist in JIA.  A total of 11 patients (median age of 12.5 years, range of 2 to 16), 15 wrists with clinically active arthritis were assessed clinically by US and color Doppler prior to and 1 and 4 weeks after US-guided steroid injection.  US detected synovitis in the radio-carpal joints, the mid-carpal joints, and the tendon sheaths in 87 %, 53 % and 33 % of the wrists, respectively.  Multiple compartments were involved in 67 %.  US-guidance allowed accurate placement of steroid in all 21 injected compartments, with a low rate of subcutaneous atrophy.  Synovial hypertrophy was normalized in 86 % of the wrists, hyperemia in 91 %, and clinically active arthritis in 80 %.  The authors concluded that US enabled detection of synovial inflammation in compartments that were difficult to evaluate clinically and exact guidance of injections, and it was valuable for follow-up examinations.  Normalization of synovitis was achieved in most cases, which supported the notion that US was an important tool in management of wrist involvement in JIA.

The authors stated that a drawback of this study was that the US assessments, were evaluated for accuracy by only 1 experienced musculoskeletal radiologist.  In addition, the US examination protocol did not include the radio-ulnar joint, and hence these investigators could not rule out any synovitis in this compartment.  Accordingly, in the future these researchers would use a revised and more appropriate scanning protocol for JIA that includes the radio-ulnar joint.

Leversedge et al (2016) stated that confirmation of pertinent anatomy and accurate needle placement for De Quervain injection may improve outcomes and limit complications.  These researchers examined the accuracy of the 1st extensor compartment in regard to the following: (i) anatomic assessment, (ii) needle placement without imaging guidance, and (iii) US-guided injection with priority for the extensor pollicis brevis sub-compartment.  Anatomic assessment and US-guided first extensor compartment injection was completed in 50 cadaver specimens.  Initial needle placement was carried out without the guidance of US; its final position was evaluated with US.  Then, using US, 1-ml of India ink was injected into the extensor pollicis brevis compartment.  Open evaluation confirmed pertinent anatomy and injection accuracy.  A sub-compartment of the 1st extensor compartment was identified in 27 of 50 wrists; 18 of 27 compartments were complete and 9 of 27 were incomplete, with US evaluation having an accuracy rate of 94 %.  Accurate needle placement occurred in 26 of 50 wrists (52 %) when US was not used, but only 2 of 27 needles (7 %) were located within the extensor pollicis brevis sub-compartment.  US-guided injection was 100 % accurate (50 out of 50) and extensor pollicis brevis injection was 96 % accurate (26 of 27) when 2 compartments were present.  Minimal extravasation was identified in 6 of 50 wrists (12 %).  The authors concluded that US-guided de Quervain injection improved injection accuracy through the visualization of compartmental anatomy and needle placement and may improve clinical outcomes by minimizing complications associated with extra-compartmental injection.

Milani and Lin (2018) noted that de Quervain tenosynovitis is a stenosing tenosynovitis of the 1st dorsal compartment of the wrist that could lead to painful functional impairment of the upper limb.  This case presentation described a rare adverse effect of corticosteroid injection (CSI) involving local skin atrophy and hypo-pigmentation with proximal linear extension.  In this case, hypo-pigmentation developed from the wrist to beyond the elbow after CSI with US guidance and targeted placement of the injectate in the extensor tendon sheath of the 1st dorsal compartment.  Dermal complications of CSI were rare but notable and potentially disfiguring events that should be discussed with every patient during the informed consent process before soft tissue CSIs.

Kurkis et al (2019) stated that ganglion cysts are the most frequent soft tissue tumor encountered in the upper extremity (UE) and are commonly treated by aspiration or by surgical excision; and US is a promising addition to traditional aspiration, as it allows for visualization of the needle within the ganglion before aspiration.  These researchers examined if ganglion cysts of the wrist were less likely to reoccur if they were aspirated under US guidance versus "blind" aspiration without the use of US guidance.  They also studied if patient functionality change based on whether or not the cyst recurred?  A total of 52 patients were successfully contacted and recurrence rates were compared between those whose cyst was treated with US-guided (n = 13) with those whose cyst was treated with blind aspiration (n = 39).  Mean follow-up time was 2.9 years.  Recurrence rates were 69 % (n = 9) and 74 % (n = 29) for the US-guided and blind aspiration groups, respectively (p-value: 0.73), showing no significant difference in recurrences of wrist ganglion between the 2 groups.  A metric of functionality (Quick-DASH [Disabilities of the Arm, Shoulder, and Hand]) revealed worse outcomes in patients who experienced return of ganglion cyst after aspiration versus those who did not.  The authors concluded that additional studies with improved sample sizes are needed to demonstrate the superiority of US-guided aspiration versus blind aspiration.  Due to a high recurrence rate following aspiration (both US-guided and blinded), a lower threshold for surgical intervention is likely reasonable.

These researchers stated that future studies should look toward a randomized, prospective controlled trial to examine the possible benefit of US-guided aspiration of ganglion cysts of the wrist.  Furthermore, this study could be expanded to examine the role of US in the management of ganglion cysts in other anatomical locations beyond the wrist.  More research would also be useful in evaluating any morbidity associated with US-guided aspiration.  Although it can be assumed that procedure-related morbidity and complications would likely be less with aspiration in comparison with open resection, it would be useful to examine if US guidance led to an improvement in treatment-associated morbidity compared with morbidity and complications associated with blind aspiration.

Furthermore, an UpToDate review on “Ganglion cysts of the wrist and hand” (De Geyser, 2021) states that “If available, ultrasonography is useful in the diagnosis of ganglia.  Most ganglia have well-defined margins, thick walls, and acoustic enhancement.  A solid-appearing ganglion, although unusual, may mimic a benign neoplasm”.

Gregoire and Guigal (2022) stated that ganglion cysts of the dorsal aspect of the wrist are a benign pathology often encountered in consultations for hand surgery.  Their treatment, irrespective of the type, presents a risk of recurrence and there is no consensus on the management to adopt.  Medical treatments such as corticosteroid injections have recurrence rates between 8 % and 74 %.  Surgical treatments appeared to have better results, with less disparate failure rates, at around 15 %.  In a retrospective study, these investigators examined the effectiveness of the aspiration and injection of corticosteroids under US guidance in the treatment of 85 ganglion cysts of the dorsal aspect of the wrist.  This trial included 99 patients suffering from a non-occult ganglion cyst of the dorsal aspect of the wrist, who had received a referral for aspiration, and subsequent injection of corticosteroids between January 2015 and December 2020.  Data collection was carried out by the analysis of files on the institution's software, and by a phone call.  Data such as age, sex, pre- and post-treatment Quick-DASH score, as well as recurrence and 2nd-line treatments were collected.  The average age of this cohort was 31 years, with a 65 % female predominance.  The recurrence rate after a 1st injection was 73.2 % with a mean follow-up of 34 months.  The Quick-DASH score improved significantly by 26.2 points out of 100 in non-injected patients, and by 18.6 points out of 100 after injection, whether the cyst recurred or not.  The authors concluded that with 73.2 % recurrence, corticosteroid injections did not appear to be effective in treating dorsal ganglion cysts of the wrist.  They resulted in an improvement in the functional score of the wrist, but not significantly compared to treatment abstinence.  Level of Evidence: IV.

Gluteal Nerve Injection

In a cadaveric study, Finnoff et al (2008) compared the accuracy of ultrasound (US)-guided piriformis injections with fluoroscopically-guided contrast-controlled piriformis injections.  A total of 20 piriformis muscles in 10 un-embalmed cadavers were injected with liquid latex using both fluoroscopically-guided contrast-controlled and US-guided injection techniques.  All injections were performed by the same experienced individual.  Two different colors of liquid latex were used to differentiate injection placement for each procedure, and the injection order was randomized.  The gluteal regions were subsequently dissected by an individual blinded to the injection technique.  Colored latex observed within the piriformis muscle, sheath, or both was considered an accurate injection; 19 of 20 US-guided injections (95 %) correctly placed the liquid latex within the piriformis muscle, whereas only 6 of the 20 fluoroscopically-guided contrast-controlled injections (30 %) were accurate (p = 0.001).  The liquid latex in 13 of the 14 missed fluoroscopically-guided contrast-controlled piriformis injections and the single missed US-guided injection was found within the gluteus maximus muscle.  In the single remaining missed fluoroscopically-guided contrast-controlled piriformis injection, the liquid latex was found within the sciatic nerve.  The authors concluded that in this cadaveric model, US-guided piriformis injections were significantly more accurate than fluoroscopically-guided contrast-controlled injections.  Despite the use of bony landmarks and contrast, most of the fluoroscopically attempted piriformis injections were placed superficially within the gluteus maximus.  Clinicians performing piriformis injections should be aware of the potential pitfalls of fluoroscopically-guided contrast-controlled piriformis injections and consider using US guidance to ensure correct needle placement.

Smith et al (2012) described and validated US-guided techniques for injecting the obturator internus (OI) muscle or bursa using a cadaveric model.  A single experienced operator completed 10 US-guided OI injections in 5 un-embalmed cadaveric pelvis specimens (4 female and 1 male, aged 71 to 89 years with body mass indices (BMI) of 15.5 to 24.2 kg/m2); 4 different techniques were used:

  1. OI tendon sheath (4 injections),
  2. OI intra-muscular (2 injections),
  3. OI bursa trans-tendinous (2 injections), and
  4. OI bursa short-axis (2 injections). 

In each case, the operator injected 1.5-ml of diluted yellow latex using direct US guidance and a 22-G, 87.5-mm (3.5-in) needle; 72 hours later, study co-investigators dissected each specimen to examine injectate placement.  All 10 OI region injections accurately placed latex into the primary target site; 2 of the 4 OI tendon sheath injections produced overflow into the underlying OI bursa.  Both OI intra-muscular injections delivered 100 % of the latex within the OI.  All 4 OI bursa injections (2 trans-tendinous and 2 short-axis) delivered 100 % of the latex into the OI bursa, with the exception that 1 OI bursa trans-tendinous injection produced minimal overflow into the OI itself.  No injection resulted in injury to the sciatic nerve or gluteal arteries, and no injectate overflow occurred outside the confines of the OI or its bursa.  The authors concluded that the results of this study showed that US-guided injections into the OI or its bursa were feasible and, thus, may play a role in the diagnosis and management of patients presenting with gluteal and "retro-trochanteric" pain syndromes.

Dillow et al (2013) stated that the para-sacral (PS) approach to sciatic nerve blockade has the potential for safe and effective use in children, but has never been studied in this population.  Its potential advantages include increased posterior cutaneous nerve block reliability, potential for hip joint analgesia, and decreased nerve depth, making US guidance easier.  These researchers examined the efficacy of an US-guided PS sciatic nerve block in children.  A total of 19 patients, aged 1 to 16 years, scheduled for lower limb surgery with peripheral nerve blockade (PNB) were prospectively enrolled.  A PS sciatic block was performed using both US guidance and nerve stimulation, and 0.5 ml/kg ropivacaine 0.2 % (maximum 20 ml) was administered.  Patient demographics, the time to perform the block, the lowest intensity of nerve stimulation, evoked response, identification of gluteal arteries, and amount of narcotic given were recorded.  Post-operatively, pain scores, block success or failure, block duration, and complications were recorded.  The block was performed using the PS approach in 95 % of the cases.  The success rate was 100 % in the PS sciatic blocks performed.  The pain scores for all patients in the first post-surgical hour were 0, except 1 patient that had a pain score of 3 of 10 at 30 mins; his pain improved to 0 of 10 after administration of 1 dose of fentanyl and distraction techniques.  The blocks lasted 17.3 ± 5.4 hours.  No complications were identified.  The authors concluded that the PS approach was an effective option for sciatic nerve blockade to provide post-operative pain relief in children having lower extremity surgery.

Gluteal Tendon Sheath Injections for Hip and/or Low Back Pain

In a single-case report, Chen et al (2017) described what these investigators believed was the 1st case of a patient with obturator internus tendinitis and bursitis successfully treated with a corticosteroid injection using a trans-tendinous lateral to medial approach.  The patient presented with right gluteal pain not relieved by physical therapy or right hip and ischial bursa corticosteroid injections.  Pelvic and lumbar spine MRIs and EMG/NCS findings were unremarkable.  Physical examination demonstrated tenderness to palpation at the right middle lower gluteal region.  Ultrasound (US) imaging with sono-palpation identified the maximal local tender point as the right obturator internus muscle and/or its underlying bursa.  A 22-G 3.5-inch needle was inserted in-plane to the transducer and longitudinal to the obturator internus from a lateral to medial direction, an approach previously described in cadavers.  The obturator internus tendon sheath and bursa were injected with 2.5-ml of 0.5 % lidocaine combined with 10-mg of triamcinolone.  The patient reported immediate complete relief of pain with continued relief at 2 and 6 months post-injection.  The authors concluded that this case report demonstrated an injection of the obturator internus tendon sheath and bursa using a trans-tendinous approach, which may be successful for treatment of patients presenting with persistent gluteal pain from obturator internus tendinitis and bursitis.

UpToDate reviews on “Treatment of acute low back pain” (Knight et al, 2021), and “Approach to the adult with unspecified hip pain” (Paoloni, 2021) do not mention gluteal tendon sheath injections as a management / therapeutic option.

Hydrodissection of the Dorsal Scapular Nerve and Middle/Inferior Trapezius, Rhomboids for Peripheral Nerve Entrapment/Shoulder Pain

Kimura et al (2020) stated that an US-guided inter-fascial injection, which targets the space between the epimysia, is often carried out for myofascial neck and shoulder pain.  However, the relationship between the injection volume and clinical effectiveness has been controversial.  In a cadaveric study, these researchers measured the distribution of a small amount of pigment solution injected into the inter-fascial space.  They carried out 20 US-guided injections with pigment solutions of 1.0-ml each into the space between the trapezius muscle and rhomboid muscle bilaterally on 10 cadaver specimens.  Cadavers were then dissected and macroscopically examined for pigment distribution on the fascia of the muscular surfaces.  The pigment distribution area of each injection site was visually confirmed and calculated using automatic area calculation software.  Pigment solution exclusively within the inter-fascial space was visually confirmed in 95 % (19/20) of injection sites.  The median pigmented surface area (IQR) was 24.50 (16.17 to 30.76) cm2 on the deep side of the trapezius muscle and 18.82 (13.04 to 24.79) cm2 on the superficial side of rhomboid muscle; these measurements were statistically significantly different (p = 0.033).  The authors concluded that a pigment solution comprising as little as 1.0-ml injected under US guidance separated 2 adjacent muscles and spread to the wide area within the inter-fascial space.  The difference in the pigment distribution area between the 2 adjacent muscles could be explained by the path made by the injection needle and several layers of fascia between the epimysium.

Buntragulpoontawee et al (2021) noted that peripheral nerve entrapment syndromes commonly result in pain, discomfort, and ensuing sensory and motor impairment.  Many conservative measures have been proposed as treatment, local injection being one of those measures.  Now with high-resolution US, anatomical details can be visualized allowing diagnosis and more accurate injection treatment.  US-guided injection technique using a range of injectates to mechanically release and decompress the entrapped nerves has therefore developed called hydrodissection or perineural injection therapy.  Several different injectates from normal saline, local anesthetics, corticosteroids, 5 % dextrose in water (D5W), and PRP are available and present clinical challenges when selecting agents regarding effectiveness and safety.  In a systematic review, these investigators examined the clinical evidence and mechanism of different commonly used injectates for US-guided hydrodissection for the treatment of entrapment neuropathy.  A total of 4 databases, including PubMed, Embase, Scopus, and Cochrane were systematically searched from the inception of the database up to August 22, 2020.  Studies examining the safety and effectiveness of different commonly used injectates for US-guided hydrodissection entrapment neuropathy treatment were included.  Injectate efficacy presented clinical effects on pain intensity, clinical symptoms/function, and physical performance, electrodiagnostic findings, and nerve CSAs.  Safety outcomes and mechanism of action of each injectate were also described.  From 10 US-guided hydrodissection studies, 9 studies were conducted in carpal tunnel syndrome (CTS) and 1 study was performed in ulnar neuropathy at the elbow.  All studies compared different interventions with different comparisons.  Injectates included normal saline, D5W, corticosteroids, local anesthetics, hyaluronidase, and PRP; 5 studies examined the use of PRP or PRP plus splinting comparisons.  Both D5W and PRP showed a consistently favorable outcome than those in the control group or corticosteroids.  The improved outcomes were also observed in comparison groups using injections with normal saline, local anesthetics, or corticosteroids, or splinting.  No serious AEs were reported.  Local steroid injection side effects were reported in only 1 study.  The authors concluded that US-guided hydrodissection was a safe and effective treatment for peripheral nerve entrapment.  Injectate selection should be considered based on the injectate mechanism, effectiveness, and safety profile.

The authors stated that this systematic review had several drawbacks.  First, all 10 studies compared different interventions and comparisons, none could be combined for further analysis.  Second, of the 10 studies, 3 were from the same investigator's group, this might limit the generalization of results as the study population was limited.  Third, the follow-up interval was rather diverse with a maximum follow-up time at 6 months, which might be insufficient for evaluating regenerative effects.  Fourth, the different injected volume among the studies might also vary the clinical outcome as larger volume tended to provide greater mechanical decompression.  These researchers stated that to further enhance knowledge of US-guided hydrodissection procedure, more studies on different nerves and locations are needed as well as in varied population groups to promote generalizability.  Furthermore, for PRP and D5W studies of longer duration than 6months should be carried out.  For future PRP studies, a full PRP preparation protocol together with detailed PRP components should be explained thoroughly as the information will be very helpful when comparing studies.

Neo et al (2022) stated that hydrodissection is an US-guided technique that has received more attention recently for its role in nerve entrapment syndromes.  In a systematic review, these researchers examined the safety and effectiveness of hydrodissection in CTS and investigated the ideal parameters for injectate type, dosage, volume, and frequency; injection approach and technique; as well as operator experience and training required.  They searched the Embase, Medline, and PubMed databases with supplemental searches in the CINAHL, Web of Science, and Google Scholar databases for relevant RCTs.  Primary outcome measures were adverse outcomes and clinical effectiveness.  A total of 6 RCTs involving 356 wrists were included.  All studies used US guidance in their interventions.  No safety-related adverse outcomes were found, although not all studies declared this.  Only 1 study was placebo-controlled and revealed symptomatic as well as functional improvements at 6 months, whereas the rest examined hydrodissection with different injectate types.  The authors concluded that nerve hydrodissection for CTS could be safely carried out under US guidance; however, it is unclear if the hydrodissection mechanism truly resulted in improvements in clinical outcomes.  These researchers were also unable to draw conclusions regarding the ideal procedure-related parameters; they recommended that future work should not only examine the safety and clinical effectiveness but also attempt to clarify the ideal procedure-related parameters.

Iliopsoas Bursa Injection

Blaichman et al (2020) noted that hip pain is a commonly reported primary symptom with many potential causes.  The causal entity can remain elusive, even after clinical history review, physical examination, and diagnostic imaging.  Although there are many options for definitive treatment, many of these procedures are invasive, are associated with risk of morbidity, and can be unsuccessful, with lengthy revision surgery required.  Percutaneous musculoskeletal intervention is an attractive alternative to more invasive procedures and an indispensable tool for evaluating and managing hip pain.  Ultrasonography (US) is an ideal modality for imaging guidance owing to its low cost, portability, lack of ionizing radiation, and capability for real-time visualization of soft-tissue and bone structures during intervention.  These investigators evaluated both common and advanced US-guided procedures involving the pelvis and hip, including anesthetic and corticosteroid injections, percutaneous viscosupplementation, platelet-rich plasma (PRP) injection to promote tendon healing, and micro-wave ablation (MWA) for neurolysis.  In addition, specific anatomic structures implicated in hip pain were discussed and included the hip joint, iliopsoas bursa, ilio-inguinal nerve, lateral femoral cutaneous nerve, greater trochanteric bursa, ilio-tibial band, ischio-gluteal bursa, hamstring tendon origin, piriformis muscle, and quadratus femoris muscle.  The relevant US-depicted anatomy and principles underlying technically successful interventions also were discussed.  Familiarity with these techniques could aid radiologists in assuming an important role in the care of patients with hip pain.

Furthermore, an UpToDate review on "Musculoskeletal ultrasonography: Guided injection and aspiration of joints and related structures" (Bruyn, 2020) does not mention iliopsoas bursa injection as an indication of US guidance.

Iliopsoas Tendon Injection

Sofka et al (2001) examined the use of ultrasonographic (US) guidance for intervention in the musculoskeletal system.  All interventional musculoskeletal procedures using US guidance performed at the authors’ institution from July 1998 through November 1999 were reviewed.  Examinations were performed using either a linear or curved phased array transducer, based on depth and local geometry.  The choice of needle was likewise optimized for specific anatomic conditions.  A total of 195 procedures were performed on 167 patients from July 1998 through November 1999; 31 procedures had magnetic resonance (MR) correlation within 6 months beforehand.  Excluding large-joint aspirations and injections, these investigators found that 180 of the procedures were more readily performed using US than any other imaging modality.  These included therapeutic injections into tendon sheaths (biceps, flexor digitorum longus, posterior tibial, and iliopsoas [peritendinous injection; n = 7]), Morton's neuromas, plantar fascia, wrist ganglia, and tarsal tunnel cysts; peritendinous hamstring injections; and synovial cyst and muscle biopsies.  In all cases, the target of interest was identified easily with US, and needle position was documented readily.  Also, in all cases, aspiration or medication delivery to the site of interest was observed during real-time and was documented on post-procedure images of the area.  No significant complications (e.g., bleeding, infection, and neurovascular compromise) were encountered during or immediately after any procedure.  The authors concluded that US is a readily available imaging modality useful for guiding interventional procedures in the musculoskeletal system.  The ability to document exact needle placement in real-time confirmed accurate placement of therapeutic injections, fluid aspiration, and soft tissue biopsies.

Blaichman et al (2020) noted that hip pain is a commonly reported primary symptom with many potential causes.  The causal entity can remain elusive, even after clinical history review, physical examination, and diagnostic imaging.  Although there are many options for definitive treatment, many of these procedures are invasive, are associated with risk of morbidity, and can be unsuccessful, with lengthy revision surgery required.  Percutaneous musculoskeletal intervention is an attractive alternative to more invasive procedures and an indispensable tool for evaluating and managing hip pain.  Ultrasonography is an ideal modality for imaging guidance owing to its low cost, portability, lack of ionizing radiation, and capability for real-time visualization of soft-tissue and bone structures during intervention.  These investigators reviewed both common and advanced US-guided procedures involving the pelvis and hip, including anesthetic and corticosteroid injections, percutaneous viscosupplementation, platelet-rich plasma (PRP) injection to promote tendon healing, and microwave ablation for neurolysis.  In addition, specific anatomic structures implicated in hip pain were discussed and included the hip joint, iliopsoas bursa, ilio-inguinal nerve, lateral femoral cutaneous nerve, greater trochanteric bursa, iliotibial band, ischio-gluteal bursa, hamstring tendon origin, piriformis muscle, and quadratus femoris muscle.  The relevant US-depicted anatomy and principles underlying technically successful interventions also were discussed.  Familiarity with these techniques could aid radiologists in assuming an important role in the care of patients with hip pain.

Infiltration between the Popliteal Artery and Capsule of the Knee (IPACK) Block for Pain Control Following Anterior Cruciate Ligament (ACL) Repair

Thobhani et al (2017) stated that novel regional techniques, including the adductor canal block (ACB) and the local anesthetic infiltration between the popliteal artery and capsule of the knee (IPACK) block, provide an alternative approach for controlling pain following total knee arthroplasty (TKA).  This study compared 3 regional techniques (femoral nerve catheter [FNC] block alone, FNC block with IPACK, and ACB with IPACK) on pain scores, opioid consumption, performance during physical therapy, and hospital length of stay (LOS) in patients undergoing TKA.  All patients had a continuous peri-neural infusion, either FNC block or ACB.  Patients in the IPACK block groups also received a single injection 30-ml IPACK block of 0.25 % ropivacaine.  Pain scores and opioid consumption were recorded at post-anesthesia care unit (PACU) discharge and again at 8-hour intervals for 48 hours.  Physical therapy performance was measured on post-operative days (POD) 1 and 2, and hospital LOS was recorded.  These researchers found no significant differences in the 3 groups with regard to baseline patient demographics.  Although these investigators observed no differences in pain scores between the 3 groups, opioid consumption was significantly reduced in the FNC with IPACK group.  Physical therapy performance was significantly better on POD 1 in the ACB with IPACK group compared to the other 2 groups.  Hospital LOS was significantly shorter in the ACB with IPACK group.  The authors concluded that the findings of this study demonstrated that an IPACK block reduced opioid consumption by providing effective supplemental analgesia following TKA compared to the FNC-only technique; ACB with IPACK provided equivalent analgesia and improved physical therapy performance, allowing earlier hospital discharge.

The authors stated that this study had several drawbacks.  Because these investigators identified no patients who would fit the criteria to receive ACB only during the study period, this study lacked a group that received ACB only, which would allow better analysis of the contribution of the IPACK block to an ACB.  Because the ACB has gained attention by providing adequate analgesia to the anterior knee while minimizing motor impairment, addition of the IPACK block could improve posterior knee analgesia without sacrificing distal motor and sensory impairment.  Comparing ACB only to ACB with IPACK block should be a goal for future research.  Nevertheless, no prior publications had described the effects of the IPACK block for addressing posterior knee pain following TKA, and thus the opioid-sparing effect of the IPACK block when combined with the FNC block is a novel finding.  Retrospective studies may suffer from assignment bias, possibly resulting in baseline differences between groups.  However, the consecutive enrollment of patients in this study may have limited selection bias.  In addition, this trial was a descriptive study of the benefits of a novel approach to regional analgesia for a common surgical procedure.  An investigator needs to know a clinical delta, the difference in expectation that one regional technique provides compared to another technique, to calculate sample size.  Because of the novel approach of this study, such information was not available, so this study could suffer from assignment bias.  However, a strength of this study was that it allowed other investigator groups to validate these findings, and when needed, to use these findings to calculate a clinical delta for the appropriate sample size needed for a prospective RCT.

Sankineani et al (2018) noted that ACB is a peripheral nerve blockade technique that provides good pain control in patients undergoing TKA, which however does not relieve posterior knee pain.  The recent technique of an US-guided IPACK has shown promising results in providing significant posterior knee analgesia without affecting the motor nerves.  These researchers carried out a prospective study in 120 patients undergoing unilateral TKA.  The initial 60 consecutive patients received ACB + IPACK (Group 1, n = 60), and the subsequent 60 patients received ACB alone (Group 2, n = 60).  All patients were evaluated with visual analog scale (VAS) score for pain recorded at 8 hours, POD 1 and POD 2 after the surgery.  The secondary outcome measures were range of movement (ROM) and ambulation distance.  VAS score showed significantly (p < 0.005) better values in ACB + IPACK group compared to the ACB group.  The mean ROM of knee and ambulation distance also showed significantly better values in ACB + IPACK group compared to the ACB group.  The authors concluded that ACB + IPACK is a promising technique that offered improved pain management in the immediate post-operative period without affecting the motor function around the knee joint resulting in better ROM and ambulation compared to ACB alone.  This was a relatively small study (n = 60 in the ACB + IPACK group); and its findings were confounded by the combined use of ACB and IPACK.

Kim et al (2019) stated that peri-articular injections (PAIs) are becoming a staple component of multi-modal joint pathways.  Motor-sparing peripheral nerve blocks, such as the IPACK block and the ACB, may augment PAI in multi-modal analgesic pathways for TKA, but supporting literature remains rare.  These researchers hypothesized that the addition of ACB and IPACK block to PAI would lower pain on ambulation on POD 1 compared to PAI alone.  This triple-blinded, RCT included 86 patients undergoing unilateral TKA.  Patients either received a PAI (control group, n = 43), or an IPACK block with an ACB and modified PAI (intervention group, n = 43).  The primary outcome was pain on ambulation on POD 1; secondary outcomes included NRS pain scores, patient satisfaction, and opioid consumption.  The intervention group reported significantly lower NRS pain scores on ambulation than the control group on POD 1 (difference in means [95 % CI]: -3.3 [-4.0 to -2.7]; p < 0.001).  In addition, NRS pain scores on ambulation on POD 0 (-3.5 [-4.3 to -2.7]; p < 0.001) and POD 2 (-1.0 [-1.9 to -0.1]; p = 0.033) were significantly lower.  Patients in the intervention group were more satisfied, had less opioid consumption (p = 0.005, PACU, p = 0.028, POD 0), less intravenous opioids (p < 0.001), and reduced need for intravenous PCA (p = 0.037).  The authors concluded that the addition of IPACK block and ACB to PAI significantly improved analgesia and reduced opioid consumption after TKA compared to PAI alone.  They stated that this study strongly supported IPACK block and ACB use within a multi-modal analgesic pathway.  This was a relatively small study (n = 43 in the ACB + IPACK block + PAI group); and its findings were confounded by the combined use of ACB, IPACK and PAT.

Injection of Deep Peroneal Nerve for the Treatment of Peroneal Neuritis

In a retrospective study, Walter et al (2017) described a 4-year clinical experience with US-guided therapeutic perineural injections of peripheral nerves about the foot and ankle.  These investigators carried out analysis of foot and ankle perineural injections performed between January 2012 and August 2016.  Demographics, clinical indications, presence of structural pathology, immediate and interval pain relief, as well as complications were recorded.  A total of 59 therapeutic injections were performed among 46 patients, accounting for multiple injections in a single visit or multiple visits (mean age of 43 years; range of 18 to 75, 31 female (67 %) and 15 male (33 %).  Most commonly, perineural injections entailed the hallux branch of the medial plantar nerve (n = 17, 22 %).  Least commonly, perineural injections involved the saphenous nerve (n = 3, 4 %).  Other injections in this series include sural (n = 10), superficial (n = 11), and deep (n = 7) peroneal, medial (n = 5) and lateral (n = 3) plantar nerves, and the posterior tibial nerve (n = 3).  US evaluation revealed structural abnormality associated with the nerve in 30 cases (51 %) -- most commonly thickening with perineural scarring (n = 14).  Of 45 injections with complete documentation, immediate relief of symptoms was reported in 43 (96 %) cases.  Interval symptom relief was achieved in 23 injections (short-term (n = 12), intermediate-term (n = 6), and long-term (n = 5)) out of 38 for which follow-up was available (61 %).  Complications were rare, occurring in only 1 case.  The authors concluded that US-guided perineural injections about the foot and ankle were safe and provided lasting symptomatic relief for many indications.  Concomitant sonographic evaluation identified structural abnormalities that may contribute to neuropathic symptoms, allowing targeting of injection or clinical therapy.

The authors stated that this study had several drawbacks.  First, there was inconsistent follow-up with respect to long-term symptomatic relief after perineural injections.  The reliance on patient reporting of subjective symptom relief as documented in follow-up clinical notes limited the ability to draw conclusions regarding the degree of relief or functional improvement following these procedures.  Second, data regarding patient response were comprised largely of clinical follow-up by other physicians, usually orthopedic surgeons, and outcomes reporting was subject to the specific devices used by individual practitioners.  Third, other factors may have affected the outcomes of these injections such as the technical adequacy of perineural injection, which is difficult to ascertain, and its assessment is subjective.

Injection of Flexor Tendon

Reach et al (2009) stated that US is an emerging imaging modality that affords dynamic, real-time, cost-effective and surgeon-controlled visualization of the foot and ankle.  These researchers examined the accuracy of US-guided injections for common injection sites in the foot and ankle.  In 10 fresh cadaver feet, US guidance was used to inject a methylene blue-saline mixture into the 1st MTP joint, the 2nd MTP joint, the tibio-talar joint, the Achilles peritendinous space, the flexor hallucis longus sheath, the posterior tibial tendon sheath, and the subtalar joint.  Dissection was then undertaken to examine injection accuracy; US guidance allowed the avoidance of intervening neurovascular and tendinous structures.  Ultrasound-guided MTP, ankle, Achilles, posterior tibialis tendon (PTT) and flexor hallucis longus (FHL) peritendinous injections were 100 % accurate; US-guided subtalar injection was 90 % accurate.  The authors concluded that US appeared to be a highly accurate method of localizing injections into a variety of locations in the foot and ankle.  These researchers stated that US’s ability to display soft-tissue structures may be an advantage over blind injection and fluoroscopic injection techniques.  This was a cadaveric study; these preliminary findings need to be validated in well-designed human studies.

In an RCT, Picelli et al (2014a) compared the outcome of manual needle placement, electrical stimulation (ES) and US-guided techniques for BTX injection into the forearm muscles of adults with arm spasticity.  This trial included a total of 60 chronic stroke patients with wrist and fingers spasticity.  After randomization into 3 groups, each patient received BTX type A in at least 2 of these muscles: flexor carpi radialis and ulnaris, flexor digitorum superficialis and profundus (no fascicles selection).  The manual needle placement group underwent injections using palpation; the ES group received injections with ES guidance; the US group was injected under sonographic guidance.  A sole injector was used.  All patients were evaluated at baseline and 4 weeks after injection.  Outcomes measures included modified Ashworth Scale; Tardieu Scale; wrist and fingers passive ROM.  One month after injection, modified Ashworth Scale scores improved more in the ES group than the manual needle placement group (wrist: p = 0.014; fingers: p = 0.011), as well as the Tardieu angle (wrist: p = 0.008; fingers: p = 0.015) and passive ROM (wrist: p = 0.004).  Furthermore, modified Ashworth Scale scores improved more in the US group than in the manual needle placement group (wrist: p = 0.001; fingers: p = 0.003), as well as the Tardieu angle (wrist p = 0.010; fingers: p = 0.001) and passive ROM (wrist: p < 0.001; proximal interphalangeal [PIP] joints: p = 0.009).  No difference was found between the US and ES groups.  The authors concluded that instrumental guidance may improve the outcome of BTX injections into the spastic forearm muscles of stroke patients.

The main limitation of this study was the use of a sole injector.  Future studies should involve a cohort of injectors highly skilled in each technique in order to avoid any bias of personal skills.  Second, no fascicle selection was attempted during the treatment of flexor digitorum superficialis and profundus.  This may have hindered some differences in the outcome of the 3 injection techniques examined in this study according to their precision in the targeting of specific fascicles of finger flexors.  Third, there was an absence of arm function assessment.  Although this is an important issue in the treatment of arm spasticity, these researchers decided to not take it into account because longer follow-up evaluations are needed (i.e., 3 or 4 months) to observe the long-term functional effects of different injection techniques and this would have introduced some variables, such as rehabilitation, which were beyond the objectives of the present study.  Future studies should take into account all these issues and also consider that the distinction between different fascicles of finger flexors is of high relevance in improving active function.  Fourth, these investigators did not test the outcome of EMG guidance, which is another injection technique frequently used to deliver BTX, especially into the arm muscles.  In the view of the authors, even if the localization of forearm muscle by ES has been reported to probably be at least as good as that using EMG in adults with focal hand dystonia, there is a need for further, properly sized studies comparing the clinical and functional outcomes of BTX injections into the forearm spastic muscles performed with ES, EMG and US guidance.  Finally, these researchers did not take into account the BMI of their patients nor their body habitus.  This would be another important aspect in examining the accuracy of BTX injection techniques because obesity may affect the proper assessment of anatomic landmarks.

In a prospective, clinical study, Picelli et al (2014b) examined the accuracy of manual needle placement for injection of BTX type A into the forearm muscles of adults with spastic flexed wrist and clenched fist as a consequence of stroke.  A total of 41 adults with chronic stroke who were scheduled to receive BTX type A injection into the following forearm muscles: flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis and flexor digitorum profundus.  According to Huber & Heck's atlas suggestions on treatment of spasticity with BTX, surface identification of muscles to inject was carried out by means of palpation and anatomical landmarks.  Accuracy of needle placement and muscle thickness at the site of needle insertion were assessed using US.  Overall accuracy of manual needle placement evaluated using US was 51.2 %.  Accuracy was significantly higher for the finger flexors than for the wrist flexors (63.4 % versus 39.0 %).  The finger flexors were significantly thicker than the wrist flexors (mean of 1.58 cm versus 0.49 cm).  The authors concluded that instrumental guidance should be used to achieve an acceptable accuracy of needle placement when performing BTX type A injections into the forearm muscles of chronic stroke patients with spastic flexed wrist and clenched fist.

The authors stated that this study had several limitations.  First, the sample size was relatively small (n = 42).  The population size may have hindered the evaluation of differences in the accuracy of manual needle placement without instrumental guidance for comparisons of flexor carpi radialis (FCR) versus flexor carpi ulnaris (FCU) and flexor digitorum superficialis (FDS) versus flexor digitorum profundus (FDP).  Second, no fascicles selection was attempted during the treatment of FDS and FDP.  This may have led to an over-estimation of the accuracy of needle placement into the finger flexors, which may be lower with regard to the targeting of specific fascicles of these muscles.  Localization of each fascicle of the FDS and FDP is important to ensure an effect on each digit.  However, the main objective of this trial was not to compare the effects of different injection techniques in the treatment of UL spasticity, but to examine the accuracy of not instrument-guided BTX-A injections into the spastic forearm muscles.  This was mainly because manual needle placement without instrumental guidance is widely used to inject BTX-A into the wrist and finger flexors, despite the fact that it is not recommended for treating small and deep-seated muscles.  Thus, the outcome chosen was the accuracy of needle placement into (every part of) the targeted muscle and its thickness, not taking into account the selection of fascicles.  Third, there was a lack of comparison between the accuracy of manual needle placement without instrumental guidance and EMG/ES-guided approaches.  This was because US is the only tool that enables checking of the accuracy of intra-muscular BTX-A injections as well as examination of muscle thickness, which were the objectives of the current study.  Furthermore, considering that these investigators used US only to perform anatomical evaluations, they were confident that its operator dependence did not affect the findings.  Fourth, these researchers studied only a single injection site for each muscle.  Fifth, these investigators did not evaluate the thickness of subcutaneous tissue.  They stated that future studies involving a larger population and other muscles, such as brachioradialis, brachialis, biceps brachii, pronator teres, pronator quadratus and flexor pollicis longus, which contribute to the main clinical patterns of UL spasticity are needed.

Binz et al (2022) noted that stenosing flexor tenosynovitis is commonly treated by injection of corticosteroids into the flexor tendon sheath; however, there is no consensus in the literature regarding the optimal technique, specifically when not using US guidance.  These researchers presented a cadaveric study in which 3 common techniques of flexor sheath injection were compared with regard to their accuracy and safety profiles.  A total of 15 fresh-frozen cadaver hands (60 digits) were evenly divided into 3 groups (20 digits per group).  Digits in each group were injected with methylene blue dye using 1 of the 3 techniques (palmar-to-bone, palmar supra-tendinous, and mid-axial).  The fingers were then dissected and were inspected for location of dye, as well as injury to tendon or digital nerves.  The mid-axial technique showed the greatest accuracy with the highest rate of all intra-sheath injection, 15 of 20 digits (75 %), while the palmar-to-bone technique produced the most combined intra- and extra-sheath injections, 13 of 20 digits (65 %) and the palmar supra-tendinous technique resulted in the most all extra-sheath injections, 9 of 20 digits (45 %).  The difference in rates of all intra-sheath injection was significant (p = 0.01).  The mid-axial technique also produced the fewest intra-tendinous injections (0 of 20), although this result did not reach statistical significance (p = 0.15).  The authors concluded that compared to other common non-image guided flexor tendon sheath injection techniques, the mid-axial injection technique was found to be the most accurate in producing all intra-sheath injection and least likely to result in intra-tendinous injection.

Injection of Hamstring Tendon

Fader et al (2014) stated that chronic proximal hamstring tendinopathies is a disabling activity related condition.  Currently, there is no well-accepted or extensively documented non-operative treatment option that provides consistently successful results.  In a retrospective, case-series study, these researchers examined the effectiveness of US-guided PRP injections in treating chronic proximal hamstring tendinopathies.  A total of 18 consecutive patients were analyzed.  All patients received a single injection of PRP via US guidance by a single radiologist.  Outcome measures included a questionnaire evaluating previous treatments, VAS for pain, subjective improvement, history of injury, and return-to-activity.  The patient population included 12 females and 6 males.  The average age at the time of the injection was 42.6 years (19 to 60).  Provocative activities included running, biking, swimming.  The average BMI of patients was 22.9 (17.2 to 30.2).  The average time of chronic pain before receiving the 1st injection was 32.6 months (6 to 120).  All patients had attempted other forms of non-surgical treatment before enrolling in the study.  The average VAS pre-injection was 4.6 (0 to 8).  Six months after the injection, 10/18 patients had 80 % or greater improvement in their VAS.  Overall, the average improvement was 63 % (5 to 100).  The only documented side effect was post-injection discomfort that resolved within 72 hours.  The authors concluded that chronic hamstring tendinopathy is a debilitating condition secondary to the pain, which limits an athlete's ability to perform.  For refractory cases of chronic insertional proximal hamstring injuries, PRP injections were safe and showed benefit in the majority of patients in this trial, allowing return-to-pre-injury activities.  Moreover, these investigators stated that a larger RCT with standardized outcome measures and long-term follow-up is needed to examine the validity of PRP as a therapeutic option, as well as the optimal regimen.  Level of Evidence = IV.

The authors stated that this study had 2 main drawbacks.  First, the sample size was small (n = 18) and from a generally active and fit population, possibly making broad generalization difficult.  Second, this study did not have a control group, instead, individuals acted as their own internal control, having undergone non-invasive treatment before the PRP injection. 

In a prospective, double-blind RCT, Davenport et al (2015) compared the effects of US-guided PRP and whole blood (WB) injections in patients with chronic hamstring tendinopathy.  PRP or WB was injected under US guidance into the proximal hamstring tendon in a cohort of patients with clinically suspected hamstring tendinosis.  Questionnaires were administered before injection and 2, 6, and 12 weeks and 6 months after injection.  Pain and function outcomes were measured via the modified Harris Hip Score (mHHS), Hip Outcome Scores for ADL, and sport-specific function, and International Hip Outcome Tool 33 (IHOT-33).  Diagnostic US was used to compare pre-injection and 6-month post-injection tendon appearances.  The WB group showed greater improvements in pain and function over the PRP group before 12 weeks, whereas the PRP group showed improved outcomes over WB at 6 months.  None of these between-group outcome measures, except 6-week IHOT-33, showed statistical significance.  Comparing pre-injection and 6-month scores, the PRP group showed significant improvements in ADL (p = 0.018) and IHOT-33 (p = 0.28) scores, whereas the WB group showed no significant improvements from baseline.  The WB group showed significantly decreased pain with 15-min sitting (p = 0.008) at 6 months.  US imaging showed no significant differences between PRP and WB group tendon appearances.  The authors concluded that both PRP and WB groups showed improvements in all outcome measures at 6 months.  The PRP group showed significant improvements in 6-month ADL and IHOT-33 scores.  The WB group reached significance in 15-min sitting pain.  No significant between-group differences were observed at any time-point.  Moreover, these researchers stated that further well-powered studies preferably in the form of multi-center RCTs, are needed to determine the ideal patient subset for this treatment as well as to better determine the differences in effects between PRP and WB injections for tendinopathies.  It should also be noted that this preliminary trial did not compare US guided injection with landmark-guarded injection.

The authors stated that this study had 2 main drawbacks.  First, the deep-seated nature of the tendon somewhat limited subjective grayscale assessment by US.  More quantitative metrics provided by shear wave elastography or relative strain measurements may result in more objective measures of healing response.  Alterations of tendon morphologic characteristics and signal intensity on MRI may likewise provide more sensitive measures, as opposed to conventional grayscale US imaging.  It was also important to note that the radiologists who carried out the tissue grading were not blinded and may have been a source of bias in this study.  Second, this trial had a small sample size (n = 15 for final analysis).  Some patients in the practice who may have been considered candidates were unwilling to participate in the study due to randomization, which resulted in termination of the study with relatively low participant numbers.  The small sample size also increased the risk for a selection bias.  Unless a multi-center trial is undertaken, a selection bias is unavoidable in most studies.  Although the number of patients was relatively small in this study, it was comparable to other studies in the PRP and WB literature.  Although these researchers could not predict what sample size will render investigators the ability to detect statistically significant between-group differences, they encouraged the undertaking of larger studies.  As the literature is relatively sparse regarding PRP and WB for hamstring tendinopathy, this study was an important addition to this body of literature.  Also, as this study is, to our knowledge, the 1st prospective study comparing PRP and WB for chronic hamstring tendinopathy, these investigators thought that the findings, although limited, represented an important contribution to this growing area of musculoskeletal medicine.

Furthermore, an UpToDate review on “Hamstring muscle and tendon injuries” (Fields et al, 2023) does not mention US guidance as a management/therapeutic tool.

Injection of Iliotibial Band Bursa

An UpToDate review on “Bursitis: An overview of clinical manifestations, diagnosis, and management” (Todd, 2023) states that “Limited data suggest that ultrasound-guided injections of the subacromial bursa may be more effective than a "blind" unguided injection; however, this was not validated in a large systematic review.  As ultrasound guidance is not available in real time in many practices, we do not advocate that the use of ultrasound-guidance is essential when injecting the subacromial bursa … The clinical presentation of iliopsoas bursitis is similar to intrinsic disorders of the hip, such as hip joint synovitis, labral tears, and avascular necrosis of the femoral head, all of which are usually associated with a normal plain film of the hip.  For this reason, further imaging by MRI or ultrasound may be indicated to exclude these entities.  In addition, because of the proximity of the bursa to the neurovascular bundle in the femoral canal, ultrasound guidance may be required in order to avoid an injury to this structure if needle aspiration or injection is attempted”.  Furthermore, US guidance is not mentioned in the “Summary and Recommendations” section of this UTD review.

Injection of Inter-Metatarsal Bursa

Larsen et al (2023) stated that inter-metatarsal bursitis (IMB) is an inflammation of the inter-metatarsal bursas.  The condition causes fore-foot pain with symptoms similar to those of Morton’s neuroma (MN).  Some studies suggested that IMB is a contributing factor to the development of MN, while others described the condition as a differential diagnosis.  In the literature on fore-foot pain and MN, IMB occurs repeatedly; however, little consistency is found on the implications of IMB and additionally, inadequate literature exists on how to differentiate the 2 conditions.  The orthopedic surgeon or radiologist who deals with these diseases daily might know how to differ the 2 conditions; however, limited studies on the subject made it hard to reproduce and standardize these observations.  The role of IMB in metatarsalgia is not evident.  In a systematic review, these investigators examined the diagnostic considerations of IMB and its role in metatarsalgia by identifying anatomical, histopathological, diagnostic, and treatment studies that include IMB.  Of 1,362 titles, 28 met the inclusion criteria.  They were subdivided according to topic: anatomical studies (n = 3), studies of patients with metatarsalgia (n = 10), and studies of patients with rheumatic diseases (n = 15).  The authors concluded that IMB should be considered a cause of pain in patients with metatarsalgia and patients with rheumatic diseases.  For patients presenting with spreading toes/V-sign, IMB should be a diagnostic consideration.  These investigators stated that future diagnostic studies on MN should take care to apply a protocol that is able to differentiate IMB from MN, to achieve a better understanding of their respective role in fore-foot pain.  Two treatment studies were identified in their search.  Awerbuch et al (1982) treated 50 patients; 28 had complete relief with corticosteroid injections in the IMB, while 22 had surgery, of which 20 patients had the inter-digital nerve and the IMB removed; and 2 patients only had the inter-digital nerve removed.  The 2 patients where the bursa was not removed initially had recurring symptoms and were treated later with either corticosteroid injection or excision of the bursa, both with good results.  This was in line with the findings of Espinosa et al (2010) who showed that IMB was more frequent in symptomatic post-neurectomy patients.  Hassouna et al (2007) treated 39 patients with corticosteroid injections of which 28 % had complete relief; however, the treatment effect was not evaluated according to US diagnosis of IMB or MN, even though it was stated that 31 % of the patients had IMB.  The authors discussed the limitations of this review.  They found an inconsistency in the definition of fore-foot bursas and in the stated pre-defined criteria to diagnose IMB.  These inconsistencies might reflect the limited written knowledge of IMB and because of this, each study reflected the authors’ own experience instead of a more uniform approach.  Another drawback was that many of the included studies were more than 20 years old (10 out of 28).  Due to technological advancement in the intermediate period, the conclusions from these studies might have been different in a current setting.  Among the included diagnostic studies, very few had a reference standard.  The frequent use of conservative treatment for patients with metatarsalgia and medicine for patients with autoimmune disorders all limited the possibility for specimens for histopathological evaluation.

It should be noted that there is very little room in inter-metatarsal bursa, and would be hard to miss the spot, which is palpable; therefore, the use of US guidance is not necessary.

Injection for Lateral Epicondylitis

An UpToDate review on “Musculoskeletal ultrasonography: Guided injection and aspiration of joints and related structures” (Bruyn, 2023) does not mention lateral epicondylitis (tennis elbow) injections.

Injection for Low Back Pain

In a systematic review, Hofmeister and colleagues (2019) evaluated the literature comparing US-guided injections to fluoroscopy-guided injections for the management of low back pain (LBP).  Medline, Cochrane CENTRAL Register of Controlled Trials, Embase, and NHSEED were searched from 2007 to September 26, 2017.  Inclusion criteria included: RCT design, compared US-guided and fluoroscopy-guided injections for LBP; dose and volume of medications injected were identical between trial arms, and reported original data.  A total of 101 unique records were identified, and 21 studies were considered for full-text inclusion; 9 studies formed the final data set.  Studies comparing US- and fluoroscopy-guided injections for LBP management reported no difference in pain relief, procedure time, number of needle passes, changes in disability indices, complications or AEs, post-procedure opioid consumption, or patient satisfaction.  The authors concluded that fluoroscopic guidance of injections for the management of LBP was similar in efficacy to US guidance.  These researchers stated that further study is needed to understand the exact role of US in image-guided injections.

Injection for Myositis Ossificans

Fornage et al (1999) stated that for the evaluation of soft tissue masses, US has proved to be very accurate in confirming the presence or absence of a lesion, with a very high negative predictive value (NPV).  Many soft tissue masses result from trauma, inflammation, infection, or cystic changes and are not true neoplasms.  In the proper clinical context, US could diagnose a muscular tear, hernia, myositis ossificans (MO), or rhabdomyolysis.  Retained foreign bodies are readily identified and localized with US, which could differentiate between cellulitis and abscess; and could diagnose masses resulting from tendinitis, tenosynovitis, or bursitis.  It is the modality of choice for diagnosing cysts, including intact or ruptured Baker’s cysts and ganglion cysts in the distal extremities.  Among benign neoplasms, lipomas and hemangiomas display a wide spectrum of echogenicity.  US can diagnose nerve sheath tumors by demonstrating the connection between the mass and the normal nerve.  Except for some well-differentiated liposarcomas, which may appear echogenic, most malignant tumors in the soft tissues are hypoechoic.  Real-time US is ideal for guiding large-core needle biopsy of soft tissue sarcomas.  US is extremely sensitive in detecting early recurrences following surgical excision, which are readily confirmed by US-guided FNA.  Any non-palpable mass visualized by US could be conveniently localized pre- or intra-operatively with US guidance.  Provided the examination is carried out by a well-trained operator using state-of-the-art equipment, the cost-effectiveness of US justified its use as a 1st-line examination technique in many situations involving soft tissues, with MRI being the problem-solving tool and staging procedure.  This study addressed the use of US for diagnostic purposes.

Injection for Os Trigonum Syndrome

Breidahl and Adler (1996) examined the use of US guidance in confirming intralesional injection of corticosteroids and local anesthetic into symptomatic ganglia; and proposed potential advantages of this technique.  A total of 10 patients (5 men, 5 women) underwent US-guided injection of a ganglion; 7 ganglia were near the wrist, 1 was adjacent to a finger inter-phalangeal joint and 2 were adjacent to the talus.  All were injected with a 1:1 mixture of long-acting corticosteroid and local anesthetic, the actual volume was dependent on the size of the ganglion; 3 patients had a 2nd injection 9 to 18 months following the initial injection.  In 4 patients the ganglia resolved completely.  In 5 patients there was significant improvement, with a reduction in size of the ganglion and symptomatic relief.  The authors concluded that US-guided injection insured intralesional deposition of corticosteroids and may provide an alternative to surgery in the management of symptomatic ganglia in the upper and lower extremities.  These researchers stated that they had demonstrated the effectiveness of US-guided injection in a small number of patients (n = 10; only 2 in the talus area); however, a larger series is needed to establish this approach as the preferred technique.  It is, however, not as effective as surgery, which remains the definitive treatment.

Maurel et al (2013) described the technique and clinical outcome of percutaneous injection of bone cement in the treatment of symptomatic para-articular intra-osseous cysts.  A total of 5 patients (3 men, 2 women; mean age of 35 years) with painful para-articular intra-osseous cysts were treated by percutaneous injection of bone cement under combined fluoroscopic and computed tomography (CT) guidance.  The lesions were all located in weight-bearing bones, involving the acetabulum, proximal tibia, distal tibia, talus, and calcaneus, respectively.  The average amount of bone cement injected was 2.1 ml (range of 0.6 to 3.5 ml).  Calcium phosphate cement was used in 4 cases and acrylic cement in 1 case.  There were no immediate or delayed complications.  Full pain relief was obtained between 1 week and 4 weeks following treatment.  All patients made a complete recovery and were pain-free at their last visit.  The authors concluded that percutaneous injection of bone cement was a safe and effective technique in the management of symptomatic para-articular intra-osseous cysts in this population.  This was a small (n = 5) study that examined the use of percutaneous injection of bone cement for the treatment of para-articular intraosseous cysts (1 in the talus area).

Injection of Pes Anserine Bursa

Lee et al (2019) compared the accuracy and effectiveness of US-guided versus blind pes anserinus bursa (PAB) injection in patients with pes anserinus tendino-bursitis (PATB).  A total of 47 patients with clinically diagnosed PATB were randomly assigned to a US-guided group or a blind group of steroid injection.  In the US-guided group, the injectate was delivered under sonographic visualization.  In the blind group, the conventional technique was used without any visual guidance.  After the PAB injection, the injectate location was identified using US in both groups.  Treatment effects were assessed using the VAS of knee tenderness.  Outcomes were measured before, 1 week and 4 weeks after the injection.  Both groups showed pain relieving at 1 week and 4 weeks after the injection.  The injectate in the US-guided group were found to be accurately at the PAB in all subjects, whereas blind group were found to be just in 4 of 22 subjects.  The US-guided group showed significant improvement of both of VAS scores compared to the blind group at 1 week and 4 weeks after the injection (p < 0.05).  The authors concluded that these findings suggested that US-guided PAB injection was more accurate and effective than blind injection in patients with PATB.

The authors stated that this study had several drawbacks.  First, the long-term clinical effects could not be determined because of the short-term follow-up period.  Second, the morphologic US findings of the PA tendon or bursa were not evaluated, which might help to determine the source of pain in PATB.  Third, potential differences caused by activity level were not considered despite their potential impact on the study results.  These researchers stated that further investigations are needed to resolve these drawbacks.

Cushman et al (2020) determined the current rates of use of available image guidance modalities for large joint and bursal injections, in addition to their relationships to physician demographics.  An electronic survey was sent to 3,400 members of the American Medical Society for Sports Medicine (AMSSM), examining types of guidance used for each large joint and bursal injection.  A total of 674 (19.8 %) sports medicine physicians responded to the survey.  Intra-articular hip and glenohumeral joint injections were more commonly performed with US guidance, while palpation-guidance was more common with all other injections.  Physicians who specialized in Physical Medicine & Rehabilitation (PM&R) were more likely to use US for trochanteric bursa (p = 0.007, OR = 4.16 [1.46 to 11.8]), while internal medicine-, pediatrics-, and family medicine-trained physicians were more likely to use palpation guidance for at least 1 joint (p < 0.05).  Physicians with fewer years of experience were more likely to use US for glenohumeral joint injections (p ≤ 0.002 for all age groups with less than 20 years of experience, ORs ranging from 6.3 to 9.2).  The authors concluded that palpation-guidance is the most common technique used for large joint and bursal injections, other than for glenohumeral and hip joint injections.  PM&R-trained physicians and those with less experience tend to use US more frequently.

Injection for Plantar Fasciitis

Li and co-workers (2014) noted that it is controversial whether US-guided injection of corticosteroid is superior to palpation-guided injection for plantar fasciitis (PF).  In a meta-analysis, these investigators compared the effectiveness of US-guided and palpation-guided injection of corticosteroid for the treatment of PF.   Databases (Medline, Cochrane library and Embase) and reference lists were searched from their establishment to August 30, 2013 for RCTs comparing US-guided with palpation-guided injection for PF.  The Cochrane risk of bias (ROB) tool was used to assess the methodological quality.  Outcome measurements were VAS, tenderness threshold (TT), heel tenderness index (HTI), response rate, plantar fascia thickness (PFT), hypo-echogenicity and heel pad thickness (HPT).  The statistical analysis was performed with software RevMan 5.2 and Stata 12.0.  When I2 was less than 50 %, the fixed-effects model was adopted.  Otherwise the randomized-effects model was adopted.  The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the quality of evidence.  A total of 5 RCTs with 149 patients were identified and analyzed.  Compared with palpation-guided injection, US-guided injection was superior with regard to VAS, TT, response rate, PFT and hypo-echogenicity.  However, there was no statistical significance between the 2 groups for HPT and HTI.  The authors concluded that US-guided injection of corticosteroid appeared to be more effective than palpation-guided injection; however, these findings need to be confirmed by further research with well-designed and large studies.

David and associates (2017) stated that plantar heel pain, commonly resulting from plantar fasciitis, often results in significant morbidity.  Therapeutic options include non-steroidal anti-inflammatory drugs (NSAIDs), orthoses, physical therapy, physical agents (e.g., extracorporeal shock wave therapy (ESWT), laser) and invasive procedures including steroid injections.  In a Cochrane review, these researchers examined the effects (benefits and harms) of injected corticosteroids for treating plantar heel pain in adults.  They searched the Cochrane Bone, Joint and Muscle Trauma Group Specialized Register, the Cochrane Central Register of Controlled Trials (the Cochrane Library), Medline, Embase, CINAHL, clinical trials registries and conference proceedings; latest search was March 27, 2017; RCTs and quasi-RCTs of corticosteroid injections in the treatment of plantar heel pain in adults were eligible for inclusion.  At least 2 review authors independently selected studies, assessed risk of bias and extracted data.  These investigators calculated RRs for dichotomous outcomes and mean differences (MDs) for continuous outcome measures.  They used a fixed-effect model unless heterogeneity was significant, when a random-effects model was considered.  They assessed the overall quality of evidence for individual outcomes using the GRADE approach.  These researchers  included a total of 39 studies (36 RCTs and 3 quasi-RCTs) that involved a total of 2,492 adults.  Most studies were small (median = 59 subjects).  Subjects' mean ages ranged from 34 years to 59 years.  When reported, most subjects had heel pain for several months.  The trials were usually conducted in out-patient specialty clinics of tertiary care hospitals in 17 countries.  Steroid injection was given with a local anesthetic agent in 34 trials.  Follow-up was from 1 month to over 2 years.  With one exception, trials were assessed at high risk of bias in 1or more domains, mostly relating to lack of blinding, including lack of confirmation of allocation concealment.  With 2 exceptions, these researchers rated the available evidence as very low quality, implying in each case that they were "very uncertain about the estimate".  The 39 trials covered 18 comparisons, with 6 of the 7 trials with 3 or 4 groups providing evidence towards 2 comparisons; 8 trials (724 subjects) compared steroid injection versus placebo or no treatment.  Steroid injection may lead to lower heel pain VAS (0 to 100; higher scores = worse pain) in the short-term (less than 1 month) (MD -6.38, 9 5% CI: -11.13 to -1.64; 350 subjects; 5 studies; I² = 65 %; low quality evidence).  Based on a minimal clinically significant difference (MCID) of 8 for average heel pain, the 95 % CI included a marginal clinical benefit.  This potential benefit was diminished when data were restricted to 3 placebo-controlled trials.  Steroid injection made no difference to average heel pain in the medium-term (1 to 6 months follow-up) (MD -3.47, 95 % CI: -8.43 to 1.48; 382 subjects; 6 studies; I² = 40 %; low quality evidence).  There was very low quality evidence for no effect on function in the medium-term and for an absence of serious AES (219 subjects, 4 studies).  No studies reported on other AEs, such as post-injection pain, and on return to previous activity.  There was very low quality evidence for fewer treatment failures (defined variously as persistent heel pain at 8 weeks, steroid injection at 12 weeks, and unrelieved pain at 6 months) after steroid injection.  The available evidence for other comparisons was rated as very low quality.  These researchers were therefore very uncertain of the estimates for the relative effects on people with heel pain of steroids compared with other interventions in: Tibial nerve block with anesthetics (2 trials); orthoses (4 trials); oral NSAIDs (2 trials); and intensive physiotherapy (1 trial).  Physical modalities: ESWT (5 trials); laser (2 trials); and radiation therapy (1 trial).  Other invasive procedures: locally injectable NSAID (1 trial); platelet-rich plasma injections (PRP; 5 trials); autologous blood injections (2 trials); botulinum toxin injections (2 trials); cryo-preserved human amniotic membrane injection (1 trial); localized peppering with a needle (1 trial); dry needling (1 trial); and mini-scalpel needle release (1 trial).  These investigators were also uncertain about the estimates from trials testing different techniques of local steroid injection: US-guided versus palpation-guided (5 trials); and scintigraphy-guided versus palpation-guided (1 trial).  An exploratory analysis involving pooling data from 21 trials reporting on AEs revealed 2 ruptures of plantar fascia (reported in 1 trial) and 3 injection site infections (reported in 2 trials) in 699 participants allocated to steroid injection study arms; 5 trials reported a total of 27 subjects with less serious short-term AEs in the 699 subjects allocated steroid injection study arms.  Reported treatments were analgesia, ice or both.  Given the high risk of selective reporting for these outcomes and imprecision, this evidence was rated at very low quality.  The authors found low quality evidence that local steroid injections compared with placebo or no treatment may slightly reduce heel pain up to 1month but not subsequently.  The available evidence for other outcomes of this comparison was very low quality.  Where available, the evidence from comparisons of steroid injections with other interventions used to treat heel pain and of different methods of guiding the injection was also very low quality.  Although serious AES relating to steroid injection were rare, these were under-reported and a higher risk cannot be ruled out.  The authors concluded that further research should focus on establishing the effects (benefits and harms) of injected steroids compared with placebo in typical clinical settings, subsequent to a course of unsuccessful conservative therapy.  Ideally, this should be preceded by research, including patient involvement, aimed to obtain consensus on the priority questions for treating plantar heel pain.

Li and colleagues (2018) noted that the argument on whether ESWT and US-guided corticosteroid injections (CSIs) exert an equivalent pain control or which is the better treatment for PF in adults remains to be resolved.  These researchers performed a meta-analysis to make a relatively more credible and overall assessment about which treatment method performs better pain control in treatment of PF in adults.  From the inception to July 2018, the Embase, PubMed, Web of Science, and Cochrane Library electronic databases were searched for all relevant studies.  Only RCTs focusing on comparing ESWT and CSI therapies in PF cases in adults were included.  The primary outcome measure was VAS reduction, whereas the secondary outcomes included treatment success rate, recurrence rate, function scores, and AEs.  A total of 9  RCTs involving 658 cases were included in this meta-analysis.  The findings of this meta-analysis showed that high-intensity ESWT had superior pain relief and success rates relative to the CSI group within 3 months, but the ESWT with low intensity was slightly inferior to CSI for efficacy within 3 months.  In addition, patients with CSI may tend to increase the need for the analgesic and more AES may be associated with the ESWT.  However, the ESWT and CSI presented similar recurrent rate and functional outcomes.  The authors concluded that this analysis showed that the pain relief and success rates were related to energy intensity levels, with the high-intensity ESWT had the highest probability of being the best treatment within 3 months, followed by US-guided CSI, and low-intensity ESWT.  These researchers stated that more high-quality RCTs with long-term follow-up duration are needed to further compare the differences of US-guided CSI and ESWT for adults with PF.

Furthermore, an UpToDate review on "Plantar fasciitis" (Buchbinder, 2019) states that "There is moderate-quality evidence that use of ultrasound to guide placement of the injection does not improve pain more than palpation-guided injections".

Injection of Scapholunate Ligament

The Working Group for Musculoskeletal Ultrasound in the EULAR Standing Committee’s guidelines on “Musculoskeletal ultrasound in rheumatology” (Backhaus et al, 2001) did not mention the use of US guidance for scapholunate injection.  Furthermore, an UpToDate review on “Musculoskeletal ultrasound of the wrist” (Boggess, 2023) states that “US can be a useful to evaluate inflammatory arthritis because it can help diagnose joint inflammation before initiation of arthritis treatment, assess response to treatment, and guide percutaneous aspiration or injection”.  However, US guidance for injection is not mentioned in the “Summary and Recommendations” section of this UTD review.

Injection for Shoulder Pain

Rutten and colleagues (2007) stated that blind injection of the subacromial-subdeltoid bursa (SSB) for diagnostic purposes (Neer test) or therapeutic purposes (corticosteroid therapy) is frequently used.  Poor response to previous blind injection or side effects may be due to a misplaced injection.  It is assumed that US-guided injections are more accurate than blind injections.  In a randomized study, these investigators compared the accuracy of blind injection to that of US-guided injection into the SSB.  A total of 20 consecutive patients with impingement syndrome of the shoulder were randomized for blind or US-guided injection in the SSB.  Injection was performed either by an experienced orthopedic surgeon or by an experienced musculoskeletal radiologist.  A mixture of 1-ml methylprednisolone acetate, 4-ml prilocaine hydrochloride and 0.02-ml (0.01 mmol) gadolinium DTPA was injected.  Immediately after injection, a 3D-gradient T1-weighted magnetic resonance imaging (MRI) of the shoulder was performed.  The location of the injected fluid was independently assessed by 2 radiologists who were blinded as to the injection technique used.  The accuracy of blind and US-guided injection was the same.  The fluid was injected into the bursa in all cases.  The authors concluded that blind injection into the SSB was as reliable as US-guided injection and could therefore be used in daily routine.  These researchers noted that US-guided injections may offer a useful alternative in difficult cases, such as with changed anatomy post-operatively or when there is no effective clinical outcome.

In a prospective, randomized, double-blind study, Dogu and co-workers (2012) compared the accuracy of blind versus US-guided corticosteroid injections in subacromial impingement syndrome and examined the correlation between accuracy of the injection location and clinical outcome.  A total of 46 patients with subacromial impingement syndrome were randomized for US-guided (group 1, n = 23) and blind corticosteroid injections (group 2, n = 23); MRI analysis was performed immediately after the injection.  Changes in shoulder ROM, pain, and shoulder function were recorded.  All patients were assessed before the injection and 6 weeks following the injection.  Accurate injections were performed in 15 (65 %) group 1 patients and in 16 (70 %) group 2 patients.  There was no statistically significant difference in the injection location accuracy between the 2 groups (p > 0.05).  At the end of the sixth week, regardless of whether the injected mixture was found in the subacromial region or not, all of the patients showed improvements in all of the parameters evaluated (p < 0.05).  The authors concluded that blind injections performed in the subacromial region by experienced individuals were reliably accurate and could therefore be given in daily routines.  Corticosteroid injections in the subacromial region were very effective in improving the pain and functional status of patients with subacromial impingement syndrome during the short-term follow-up.

In a systematic review and meta-analysis, Wu and colleagues (2015) examined the effectiveness of US-guided (USG) versus blind (landmark-guided, LMG) corticosteroid SSB injection in adults with shoulder pain.  Searches were performed on PubMed, Ovid Medline, Ovid Embase, Ovid Cochrane CENTRAL, Web of Science, Google Scholar, and Scopus from database inception through March 27, 2015.  Studies included trials comparing USG versus LSG injections for the treatment of adults with SSB.  Two reviewers independently performed data extraction and appraisal of the studies.  The outcome measures collected were decreased VAS and Strengths and Difficulties Questionnaire (SDQ) scores, increased shoulder function scores and shoulder abduction ROM, and the effective rate at 6 weeks after injection.  A total of 7 papers including 445 patients were reviewed; 224 received LMG injections and 221 received USG injections.  There was a statistically significant difference in favor of USG for pain score [mean difference [MD] = 1.19, 95 % CI: 0.39 to 1.98, p = 0.003] and SDQ score [MD = 5.01, 95 % CI: 1.82, 8.19, p = 0.02] at 6 weeks after injection.  Furthermore, there was a statistically significant difference between the groups, with greater improvement reported of shoulder function scores [SMD = 0.89, 95 % CI: 0.56 to 1.23, p < 0.001] and shoulder abduction ROM [MD 32.69, 95 % CI: 14.82 to 50.56, p < 0.001] in the USG group.  More effective rate was also reported with USG group and the difference was statistically significant [risk ratio (RR) = 1.6, 95 % CI: 1.02 to 2.50, p = 0.04].  The authors concluded that US-guided corticosteroid injections potentially offered a significantly greater clinical improvement over blind SSB injections in adults with shoulder pain.

In a RCT, Cole and associates (2016) examined the clinical outcome of US-guided subacromial injections compared with blind subacromial injections for subacromial impingement syndrome.  A total of 56 shoulders with subacromial impingement syndrome were randomized into 2 groups: 28 shoulders received a subacromial corticosteroid injection with US guidance (US group), and 28 shoulders received a subacromial corticosteroid injection without US guidance (blind group).  The VAS for pain with overhead activities and the American Shoulder and Elbow Surgeons (ASES) score were obtained before the injection and at 6 weeks after the injection.  The VAS score for pain with overhead activities decreased from 59 ± 5 mm (mean ± SEM) before the injection to 33 ± 6 mm at 6 weeks after the injection in the US group (p < 0.001) and from 63 ± 4 mm to 39 ± 6 mm, respectively, in the blind group (p < 0.001).  The decrease in the VAS score was not significantly different between the groups (p > 0.999).  The ASES score increased from 57 ± 2 before the injection to 68 ± 3 at 6 weeks after the injection in the US group (p < 0.01) and from 54 ± 3 before the injection to 65 ± 4 after the injection in the blind group (p < 0.01), with no significant difference between the groups (p = 0.7); 4 shoulders (14 %) in the US group and 6 shoulders (21 %) in the blind group eventually needed surgery (p = 0.7).  The authors concluded that no significant differences were found in the clinical outcome when comparing US-guided subacromial injections to blind subacromial injections for subacromial impingement syndrome.

Intercostal Nerve Block

Shankar and Eastwood (2010) noted that steroid injection around the intercostal nerves (ICN) is one of the therapeutic options for intercostal neuralgia.  The technique may be performed blindly, under fluoroscopic guidance (FSG) or with the use of USG.  This study was a retrospective comparison of image guidance for intercostal steroid injections.  After Institutional Review Board (IRB) approval, a retrospective review of all patient charts who received intercostal steroid injections from 2005 to 2009 was performed.  A total of 39 blocks were performed in that period; 12 were USG blocks and 27 FSG blocks.  The pre-procedure VAS and post-procedure VAS and the duration of pain relief were compared between the 2 techniques.  The median change in the VAS for FSG and USG were -5.000 and -4.000, respectively, and duration of pain relief with a MD of 2 weeks (95 % CI: -4 to 7).  There were 2 occasions of intravascular spread noticed with the FSG although this should not affect the study result as the needle was re-positioned and steroid injected only after contrast dye confirmation.  The authors concluded that with similar change in VAS scores and duration of pain relief between the 2 guidance methods based on this retrospective study, both image guidance techniques may offer similar pain relief.  The main drawbacks of this study were its retrospective design, small sample size (n = 12 for US guidance group), and the lack of a comparison group of "blind" injections by means of anatomic landmarks.

Bhatia et al (2013) stated that ICN injections are routinely performed under anatomic landmark or FSG for acute and chronic pain indications; US is being used increasingly to perform ICN injections, but there is lack of evidence to support the benefits of US over conventional techniques.  These researchers compared guidance with US versus anatomic landmarks for accuracy and safety of ICN injections in cadavers in a 2-phase study that included evaluation of deposition of injected dye by dissection and spread of contrast on fluoroscopy.  A cadaver experiment was performed to validate US as an imaging modality for ICN blocks.  In the first phase of the study, 12 ICN injections with 2 different volumes of dye were performed in 1 cadaver using anatomic landmarks on one side and US-guidance on the other (6 injections on each side).  The cadaver was then dissected to evaluate spread of the dye.  The second phase of the study consisted of 74 ICN injections (37 US-guided and 37 using anatomic landmarks) of contrast dye in 6 non-embalmed cadavers followed by fluoroscopy to evaluate spread of the contrast dye.  In the first phase of the study, the intercostal space was identified with US at all levels.  Injection of 2-ml of dye was sufficient to ensure complete staining of the ICN for 5 of 6 US-guided injections; but anatomic landmark guidance resulted in correct injection at only 2 of 6 intercostal spaces.  No intravascular injection was found on dissection with either of the guidance techniques.  In the second phase of the study, US-guidance was associated with a higher rate of intercostal spread of 1 ml of contrast dye on fluoroscopy compared with anatomic landmarks guidance (97 % versus 70 %; p = 0.017).  The authors concluded that US conferred higher accuracy and allowed use of lower volumes of injectate compared with anatomic landmarks as a guidance method for ICN injections in cadavers.  They stated that US may be a viable alternative to anatomic landmarks as a guidance method for ICN injections.  This was a cadaveric study.

Thallaj et al (2015) tested the hypothesis that identification and blockade of the inter-costo-brachial nerve (ICBN) can be achieved under US guidance using a small volume of local anesthetic.  A total of 28 adult male volunteers were examined; ICBN blockade was performed using 1-ml of 2 % lidocaine under US guidance.  A sensory map of the blocked area was developed relative to the medial aspect of the humeral head.  The ICBN appeared as a hyper-echoic structure.  The nerve diameter was 2.3 ± 0.28 mm, and the depth was 9 ± 0.28 mm.  The measurements of the sensory-blocked area relative to the medial aspect of the humeral head were as follows: 6.3 ± 1.6 cm anteriorly; 6.2 ± 2.9 cm posteriorly; 9.4 ± 2.9 cm proximally; and 9.2 ± 4.4 cm distally; ICBN blockade using 1-ml of local anesthetic was successful in all cases.  The authors concluded that the present study described the sonographic anatomical details of the ICBN and its sensory distribution to successfully perform selective US-guided ICBN blockade.  These investigators stated that the volunteers in this study were all men and had a normal or low BMI; therefore, the observation might not be accurate for patients with a higher BMI or who are female.  They recommended further studies to support and apply these findings to improve patient care.

In a pilot study, Wijayasinghe et al (2016) examined the feasibility of ICBN blockade and evaluated its effects on pain and sensory function in patients with persistent pain after breast cancer surgery (PPBCS).  This prospective pilot study was performed in 2 parts: Part 1 determined the sono-anatomy of the ICBN; and part 2 examined effects of the US-guided ICBN blockade in patients with PPBCS.  Part 1: 16 un-operated, pain-free BC patients underwent systematic US to establish the sono-anatomy of the ICBN.  Part 2: 6 patients with PPBCS who had pain in the axilla and upper arm were recruited for the study.  Summed pain intensity (SPI) scores and sensory function were measured before and 30 mins after the block was administered; SPI is a combined pain score of NRS at rest, movement, and 100 kPa pressure applied to the maximum point of pain using pressure algometry (max = 30).  Sensory function was measured using quantitative sensory testing, which consisted of sensory mapping, thermal thresholds, supra-threshold heat pain perception as well as heat and pressure pain thresholds.  The ICBN block was performed under US guidance and 10-ml 0.5 % bupivacaine was injected.  Outcome measures were the ability to perform the ICBN block and its analgesic and sensory effects.  Only the second intercostal space could be seen on US, which was adequate to perform the ICBN block.  The mean difference in SPI was -9 NRS points (95 % CI: -14.1 to -3.9, p = 0.006).  All patients had pre-existing areas of hypoesthesia that decreased in size in 4/6 patients after the block.  The authors concluded that they had successfully managed to block the ICBN using US guidance and demonstrated an analgesic effect in patients in PPBCS.  The authors stated that the main drawback of this pilot study was its small sample size (n= 6), but despite this, a statistically significant effect was observed.  They suggested that a RCT is needed to ascertain the role of ICBN blockade in PPBCS.

Intra-Articular Steroid Injection for the Knee

An UpToDate review on "Intraarticular and soft tissue injections: What agent(s) to inject and how frequently?" (Roberts, 2019) does not mention the utility of imaging guidance (i.e., arthrogram/fluoroscopic/ultrasound).

Ischial Bursa Injection for Ischial Bursitis

In a case report, Chen et al (2017) described what they believed was the 1st case of a patient with obturator internus tendinitis and bursitis successfully treated with a corticosteroid injection using a trans-tendinous lateral to medial approach.  The patient presented with right gluteal pain not relieved by physical therapy (PT) or right hip and ischial bursa corticosteroid injections.  Pelvic and lumbar spine MRIs and EMG/NCS findings were unremarkable.  Physical examination demonstrated tenderness to palpation at the right middle lower gluteal region.  Ultrasound imaging with sono-palpation identified the maximal local tender point as the right obturator internus muscle and/or its underlying bursa.  A 22-G 3.5-inch needle was inserted in-plane to the transducer and longitudinal to the obturator internus from a lateral to medial direction, an approach previously described in cadavers.  The obturator internus tendon sheath and bursa were injected with 2.5-ml of 0.5 % lidocaine combined with 10-mg of triamcinolone.  The patient reported immediate complete relief of pain with continued relief at 2- and 6-month post-injection.  The authors concluded that this case report showed an injection of the obturator internus tendon sheath and bursa using a trans-tendinous approach, which may be successful for the treatment of patients presenting with persistent gluteal pain from obturator internus tendinitis and bursitis.

Furthermore, an UpToDate review on “Bursitis: An overview of clinical manifestations, diagnosis, and management” (Todd, 2022) states that “Ischial bursitis -- "Weaver's bottom," or "tailor's bottom," refers to pain in the bursa that lies between the ischial prominence and the gluteus maximus.  When the patient with this condition stands erect, the muscle covers the bursa; and the patient is generally asymptomatic.  When seated, the muscle slides away; and the bursa is in direct contact with the subcutaneous tissue.  Hence, the pain is significantly accentuated when seated.  As the bursa is also adjacent to the sciatic nerve, lancinating pain, suggestive of sciatica, may occur.  This aspect of the syndrome's relationship to posture and local pressure when seated tends to distinguish it from sciatica arising from conditions of the spine.  Variants of ankylosing spondylitis, as well as other conditions causing sacroiliitis, are often associated with an enthesopathy of the iliac spine, which has common features with the symptoms of an isolated ischial bursitis.  A history and physical aimed at the possible diagnosis of a spondyloarthropathy, as well as a careful neurological evaluation, should be part of the diagnostic workup.  Management -- A therapeutic trial of NSAIDs, stretching exercises (knee to chest stretch while lying down), and the use of foam pad "doughnut" cushion are helpful.  We do not use local anesthetic-glucocorticoid injection into the site of maximum tenderness.  This is related both to the proximity of the sciatica nerve to the bursa and a concern about creating soft-tissue atrophy in this bursa whose major function is to serve as a cushion”.

Lateral Femoral Cutaneous Nerve Block for the Treatment of Post-Operative Pain After Total Hip Arthroplasty

In a retrospective study, Vandebroek et al (2014) examined the use of an US-guided femoral nerve (FN) block together with an US-guided lateral femoral cutaneous nerve (LFCN) block in addition to a patient controlled intravenous analgesia (PCIA) pump with piritramide as a strategy for post-operative pain-management after primary hip arthroplasty.  Data recorded from 32 patients undergoing primary hip arthroplasty in 2008, before peripheral blocks were used, were compared with data from 38 patients undergoing primary hip arthroplasty in 2011, when an US-guided single shot FN and LFCN block was used.  As primary endpoint the total piritramide consumption after 48 hours was analyzed.  A score on a VAS at rest and during movement was included as a secondary outcome.  Patients receiving the peripheral nerve blocks used significantly less piritramide in comparison to the patients who received no peripheral nerve blocks (p < 0.01).  Moreover, pain scores at rest and during movement were significantly lower in the group with the peripheral nerve block (p-values respectively < 0.01 and < 0.05).  The authors concluded that the findings of this retrospective study indicated that a FN block in combination with a LFCN block as supplementary post-operative analgesia after primary hip arthroplasty, could reduce the piritramide consumption.  Furthermore, patients receiving the peripheral nerve block reported lower pain scores at rest and during movement compared with the patients who did not receive a peripheral block.  However, as this was a retrospective study, conclusions have to be drawn cautiously.  Furthermore, the findings of this study were confounded by the combined use of FN block, LFCN block and a PCIA pump.

Wang et al (2015) compared the effectiveness of 2 approaches to US-guided FICB for post-operative analgesia after THA.  Approved by the Peking University Third Hospital ethics committee, a total of 60 patients undergoing selective total hip replacement in Peking Third Hospital during October 2013 to May 2014 were included.  Before induction of general anesthesia, US-guided FICB were administered.  According to probe parallel to the inguinal ligament or perpendicular to the inguinal ligament, patients were randomly divided into the Parallel group and the Perpendicular group.  Both groups were administered an equal volume mixture of 1 % ropivacaine and 1 % lidocaine, 30 ml in total.  All patients received sufentanil post-operative intravenous analgesia after surgery.  Time to US imaging, time to perform the block and total blocking time were recorded.  Loss of sensation in the distribution areas of the FN and LFCN within 30 mins were recorded.  Patients were interviewed at 4, 8, 12, 24, 36, 48 hours following block for pain intensity, time of first use of PCA, sufentanil consumption and loss of skin sensation due to the block.  The occurrence of AEs (e.g., nausea, vomiting, respiratory inhibition, pruritus or urinary retention) was also recorded.  The imaging time of the Parallel group was shorter than the Perpendicular group [(3.1 ± 1.2) mins versus (5.0 ± 1.7) mins, t = -5.128, p < 0.05)], and performance time of the Parallel group was shorter than the Perpendicular group [(5.2 ± 1.3) mins versus (7.1 ± 2.0) mins, t = -4.376, p < 0.05)].  The successful rate for FN block was 100 % both in 2 groups, while the successful rate for LFCN block in the Perpendicular group was 100 %, and 83.3 % in the Parallel group (χ² = 5.455, p < 0.05).  The block rates for LFCN at 4, 8, 12 hours after block in the Perpendicular group was higher than the Parallel group (p < 0.05).  The consumption of sufentanil in the Parallel group was significantly higher than the Perpendicular group at 8, 12, 24, 36, 48 hours after block (p < 0.05).  There were no statistically differences in post-operative pain score, time of 1st use of PCA, incidence of complications and patient's satisfaction score between the 2 groups.  The authors concluded that comparing the 2 approaches to US-guided FICB, US probe perpendicular to the inguinal ligament may offer better blocking effect of lateral cutaneous nerve and reduce post-operative sufentanil consumption; and might be more suitable for analgesic after THA.

Thybo et al (2016) noted that THA is a common procedure associated with moderate post-operative pain.  No nerve block without loss of motor function has been documented for THA.  In a randomized, placebo-controlled, blinded, parallel-group study, these researchers hypothesized that an US-guided LFCN block (LFCNB) added to a multi-modal post-operative pain regimen would reduce post-operative pain after THA.  A total of 100 patients who had a THA by the posterior approach were examined in this trial, which compared US-guided LFCN-block with either 8-ml of ropivacaine, 7.5 mg/ml, (Group Ropivacaine) or 8-ml of saline (Group Placebo) given post-operatively.  Surgery was performed under spinal anesthesia.  The primary outcome was pain (measured on a VAS) 4 hours post-blockade during 30° flexion of the hip.  Secondary outcomes were pain at rest, pain during movement, oxycodone consumption (0 to 24 hours), time-to-mobilization, ability to mobilize, and LOS.  Patients, assessors and all staff involved with patient care were blinded to the intervention.  There was no difference in primary outcome between Group Ropivacaine and Group Placebo (VAS 27 mm versus 31 mm, p = 0.41; difference -5 mm (95 % CI: -15 mm to +5 mm).  No differences in any of the secondary outcomes were observed.  No AEs, or harms, were observed during the trial.  The authors demonstrated no additional analgesic effects of a LFCNB when combined with a basic analgesic regimen with paracetamol, ibuprofen and oxycodone after THA by posterior approach.  These investigators stated that further studies are needed to examine the effect of the LFCNB among patients with higher pain scores.

In a retrospective, cohort study, Wang et al (2021) examined the safety and effectiveness of combined LFCNB and iliohypogastric/ilioinguinal nerve blocks (IHINB) on post-operative pain and functional outcomes after THA via the direct anterior approach (DAA).  Patients undergoing THA via the DAA between January 2019 and November 2019 were stratified into 2 groups based on their date of admission; 67 patients received LFCNB and IHINB along with periarticular infiltration analgesia (PIA) (nerve block group), and 75 patients received PIA alone (control group).  The outcomes included post-operative morphine consumption, post-operative pain assessed using the VAS, the QoR-15 score, and functional recovery measured as quadriceps strength, time to 1st straight leg rise, daily ambulation distance, and duration of hospitalization.  The Oxford hip score and the UCLA activity level rating were assessed at 1 and 3 months after surgery.  Furthermore, post-operative complications were recorded.  Patients were also compared based on the type of incision used during surgery (traditional longitudinal or "bikini" incision).  Patients in the nerve block group showed significantly lower post-operative morphine consumption, lower resting VAS scores within 12 hours post-operatively, lower VAS scores during motion within 24 hours post-operatively, and better QoR-15 scores on post-operative day 1.  These patients also showed significantly better functional recovery during hospitalization.  At 1-month and 3-month outpatient follow-up, the 2 groups showed no significant differences in Oxford hip score or UCLA activity level rating.  There were no significant differences in the incidence of post-operative complications.  Similar results were observed when patients were stratified by type of incision, except that the hospital LOS was similar.  The authors concluded that compared to PIA alone, a combination of LFCNB and IHINB along with PIA could improve early pain relief, reduce morphine consumption, and accelerate functional recovery, without increasing complications after THA via the DAA.  Moreover, these researchers stated that prospective studies with fewer confounding factors are needed to further examine the clinical benefits of this method.

The authors stated that the findings of this study provided preliminary support for the use of these nerve blocks for post-operative pain management; however, these results should be interpreted with caution in light of several limitations.  First, the sample size of this trial was small, and studies with larger sample sizes are still needed to validate these findings.  Second, lack of randomization in patient assignment to the nerve block or control group.  Nevertheless, the 2 groups did not differ in clinicodemographic characteristics.  The retrospective design was open to biases that would be reduced with a prospective, randomized controlled design.  Third, this study did not analyze long‐term outcomes and complications beyond 3 months after surgery.  In future studies, long‐term outcomes and complications must be studied in detail with extensive follow-up.

Lateral Pericapsular Nerve Group (PENG) Nerve Block During Total Hip Arthroplasty

Jadon et al (2020) noted that pericapsular nerve group (PENG) block is a new ultrasound (US)-guided nerve block.  It was used primarily to relieve pain in hip fracture; now, many new indications have been added.  However, dependency on US guidance for this block limits its use where US facility is poor or unavailable.  These researchers have suggested a landmark-based technique to increase the benefit of this novel nerve block.  They carried out a feasibility study to examine the successful placement of block needle, clinical efficacy of the block and block-related complications.  A total 10 patients (4 males and 6 females) with fracture hip and scheduled for hip surgery under spinal anesthesia were selected for the study.  In 4 patients, US-guided PENG block using out-of-plane approach and in 6 patients landmark- based nerve stimulator guided block was given with 20 ml 0.25 % bupivacaine and 8 mg dexamethasone.  Pain relief before and after 30 mins of block was evaluated by numeric rating scale (NRS) and comfort during spinal position was assessed by ease of spinal position score (EOSP).  All 10 patients had successful block; NRS at rest was 6 (6 to 9) versus 2 (0 to 2) and on 15 degrees limb elevation was 8 (8 to 10) versus 3 (2 to 4).  All patients could sit comfortably during spinal anesthesia and median (range) EOSP sore was 3 (2 to 3).  No complication was observed.  The authors concluded that landmark-based technique for PENG block is a feasible option and can be used safely where US facility is not available.  Nerve stimulator guidance is essential to avoid inadvertent femoral nerve injury.

Morrison et al (2021) noted that the PENG block is a novel regional analgesia technique to reduce pain after hip surgery and hip fractures.  These researchers examined current literature on the PENG block.  They performed a scoping review using the Joanna Briggs Institute framework.  All articles describing the use of PENG block as a regional analgesia and/or anesthesia technique for hip pain were considered eligible for inclusion.  Ovid Medline, Embase, CINAHL, PubMed and Google Scholar were searched.  Adult and pediatric studies were included.  Excluded were articles not available in English language, not available in full-text, related to non-orthopedic indications such as soft tissue surgery, and pelvic or femoral shaft fractures.  Database searches identified 345 articles, 20 of which could be included in the current review, with a combined patient number of 74.  Included articles comprised case reports and case series only, describing 1 to 10 patients.  In all studies, PENG block was described to provide adequate analgesia or anesthesia.  Transient motor side effects occurred only when the local anesthetic was deposited in an unintended location (n = 2).  The authors concluded that current evidence of using PENG block for hip surgery or hip pain is limited to case reports and case series only.  They stated that the PENG block is a promising regional analgesia technique as an alternative to other regional nerve blocks such as femoral nerve block or iliac fascia nerve block.  Moreover, these researchers stated that observational and experimental studies are needed to determine the safety and effectiveness of the PENG block.

Del Buono et al (2021) stated that the PENG block is a recently described US-guided technique for the blockade of the sensory nerve branches to the anterior hip joint capsule.  It was described as an analgesic block for the acute pain management after hip fracture, while subsequent studies expanded the original indication.  These investigators summarized the existing knowledge regarding the PENG block from the anatomical bases and provided an up-to-date description of the technique, applications and effects.  They reviewed the following medical literature databases for publications on PENG block: PubMed, Google Scholar, Embase, and Web of science until August 31, 2020.  Data regarding anatomy, indications, drugs and technique were also collected, reported and discussed.  These researchers selected 57 relevant publications.  Among them, 36 were case reports or case series and 12 publication were letters or correspondence; no randomized controlled trial (RCT) was identified.  The main indication is the hip-related analgesia.  The most commonly injected drug is a 20-ml long-acting local anesthetic.  There are some cases of femoral and obturator nerve block, but no major complication such as hematoma/bleeding or needle-related organ injury has been reported yet.  The authors concluded that the PENG block is a promising technique; RCTs of high methodological quality are needed to further elaborate the role of this block.

Lavage of the Shoulder Joint

Del Cura et al (2010) noted that ultrasonography (US) is the most appropriate tool for interventional procedures in the musculoskeletal system when the lesion is visible on US.  Procedures performed under US guidance include: taking biopsies; draining abscesses; bursitis; hematomas or muscle tears; treating cystic lesions; diagnostic or therapeutic arthrocentesis; injecting substances into joints or lesions; aspirating calcium deposits and extracting foreign bodies.  Although some of these procedures are often carried out without imaging guidance, US guidance improves their efficacy.  Drainage can be performed with catheters or needles and makes it possible to avoid more aggressive treatments in most cases.  Urokinase is useful for draining hematomas or fibrinous collections.  Injecting corticoids is useful in the treatment of synovial cysts, Baker's cyst, tendinitis, and non-infective arthritis.  Calcifying tendinitis of the shoulder can be treated effectively with percutaneous calcium lavage.

Sammour et al (2016) stated that musculo-skeletal US has evolved throughout the past 10 years.  This procedure allows accurate corticosteroid injections guidance.  Precision is much higher than the infiltration performed blindly or under fluoroscopy.  These researchers described their technique in US-guided infiltration of the shoulder with an overview of the results.  A total of 123 cases of US-guided infiltration of the shoulder were selected in the authors’ institution from July 2011 to June 2012.  They were divided into sub-acromial sub-deltoid bursitis, biceps tenosynovitis, acromioclavicular osteoarthritis (OA), adhesive capsulitis and calcific tendinosis lavage and aspiration.  The infiltration technique and the sonographic appearance in each condition were described.  The rate of improvement was estimated between 70 % and 80 %.  The authors concluded that US-guided infiltration provided an accurate and minimally invasive therapeutic option before any surgery.  Recovery and socio-professional integration prove to be optimal and fast.

Furthermore, an UpToDate review on "Musculoskeletal ultrasound of the shoulder" (Finnoff, 2020) states that "Calcific tendinopathy appears as hyperechoic foci within the tendon.  During the calcific phase, the calcification has significant posterior acoustic shadowing.  The posterior acoustic shadowing becomes less prominent as the calcification progresses into the resorptive phase.  Occasionally, hyperemia can be seen within the calcification or surrounding tendon tissue during the resorptive phase.  During the resorptive phase, the calcification may be amenable to treatment via US-guided lavage and aspiration of the calcific material".

Lumbar Plexus Block with Hydrodissection

Lam et al (2017) stated that deep nerve hydrodissection uses fluid injection under pressure to separate nerves from areas of suspected fascial compression, which are increasingly viewed as potential perpetuating factors in recalcitrant neuropathic pain/complex regional pain.  The usage of 5 % dextrose water (D5W) as a primary injectate for hydrodissection, with or without low-dose anesthetic, could limit anesthetic-related toxicity.  An analgesic effect of D5W upon perineural injection in patients with chronic neuropathic pain has recently been described.  These researchers described US-guided methods for hydrodissection of deep nerve structures in the upper torso, including the stellate ganglion, brachial plexus, cervical nerve roots, and paravertebral spaces.  They retrospectively reviewed the outcomes of 100 hydrodissection treatments in 26 consecutive cases with a neuropathic pain duration of 16 ± 12.2 months and the mean Numeric Pain Rating Scale (NPRS; 0 to 10 pain level) of 8.3 ± 1.3.  The mean percentage of analgesia during each treatment session involving D5W injection without anesthetic was 88.1 %  ±  9.8 %.  The pre-treatment NPRS score of 8.3 ± 1.3 improved to 1.9 ± 0.9 at 2 months after the last treatment.  Patients received 3.8 ± 2.6 treatments over 9.7 ± 7.8 months from the first treatment to the 2-month post-treatment follow-up.  Pain improvement exceeded 50 % in all cases and 75 % in half.  The authors concluded that these findings confirmed the analgesic effect of D5W injection and suggested that hydrodissection using D5W provided cumulative pain reduction.  These preliminary findings need to be validated by well-designed studies.

Median Nerve Block 

Lewis et al (2015) noted that peripheral nerve blocks can be performed using US guidance.  It is unclear if this method of nerve location has benefits over other existing methods.  This review was originally published in 2009 and was updated in 2014.  The objective of this Cochrane review was to examine if the use of US to guide peripheral nerve blockade has any advantages over other methods of peripheral nerve location.  Specifically, these researchers examined if the use of US guidance improved success rates and effectiveness of regional anesthetic blocks, by increasing the number of blocks that were assessed as adequate, and reduced the complications, such as cardio-respiratory arrest, pneumothorax or vascular puncture, associated with the performance of regional anesthetic blocks.  The authors concluded that there was evidence that peripheral nerve blocks performed by US guidance alone, or in combination with PNS, were superior in terms of improved sensory and motor block, reduced need for supplementation and fewer minor complications reported.  Using US alone shortened performance time when compared with nerve stimulation, but when used in combination with PNS it increased performance time.  The authors were unable to determine whether these findings reflect the use of US in experienced hands and it was beyond the scope of this review to consider the learning curve associated with peripheral nerve blocks by US technique compared with other methods.

In a Cochrane review, Walker et al (2019) examined if the use of US to guide peripheral nerve blockade has any advantages over other methods of peripheral nerve location.  The authors concluded that in experienced hands, US provided at least as good success rates as other methods of peripheral nerve location.  Individual studies have demonstrated that US may reduce complication rates and improve quality, performance time, and time to onset of blocks.  Due to wide variations in study outcomes these researchers chose not to combine the studies in their analysis.

In a Cochrane review, Guay et al (2019) examined if US guidance offers any clinical advantage when neuraxial and peripheral nerve blocks are performed in children in terms of decreasing failure rate or the rate of complications.  The authors concluded that US guidance for regional blockade in children probably decreased the risk of failed block.  It increased the duration of the block and probably decreased pain scores at 1 hour after surgery; there may be little or no difference in the risks of some minor complications.  These investigators stated that the 5 ongoing studies may alter the conclusions of the review once published and assessed.

Metatarsophalangeal and/or Metatarsal Cuneiform Joint Injection for the Treatment of Plantar Fibromatosis

Young et al (2018) noted that plantar fibromatosis (Ledderhose disease) is a rare, benign, hyper-proliferative fibrous tissue disorder resulting in the formation of nodules along the plantar fascia.  This condition could be locally aggressive, and often results in pain, functional disability, and decreased QOL.  Diagnosis is primarily clinical, but MRI and US are useful confirmatory adjuncts.  Given the benign nature of this condition, treatment has historically involved symptomatic management.  A multitude of conservative treatment strategies supported by varying levels of evidence have been described mostly in small-scale trials.  These therapies include steroid injections, verapamil, radiation therapy, ESWT, tamoxifen, and collagenase.  When conservative measures fail, surgical removal of fibromas and adjacent plantar fascia is often carried out, although recurrence is common.  The authors concluded that given the benign nature of this condition, conservative therapies continue to be 1st-line options for symptomatic management; however, convincing, long-term research regarding their use does not yet exist.  These investigators stated that further research is needed to determine an optimal treatment algorithm.

Jha et al (2020) stated that intra-articular injections have diagnostic and therapeutic roles in foot and ankle pathologies due to complex anatomy, small size, diverse bones, and joints with proximity in this region.  Conventionally, these injections are performed using anatomical landmark technique and/or fluoroscopic guidance.  The small joint space and needle size make the injection challenging.  Fluoroscopy is not readily available in the clinical setting; thus, ultrasound (US)-guidance for injections is increasingly being used.  These researchers compared the accuracy of intra-articular talo-navicular injections using the anatomical landmark technique versus the US-guided method.  US guidance yielded superior results in intra-articular injections of the talo-navicular joint compared to injections using palpatory method guided by anatomical landmarks.  The feet of 10 cadaveric specimens were held in neutral position by an assistant while a fellowship-trained foot-ankle orthopedic surgeon injected 2-cc of radiopaque dye using anatomical landmarks and palpation method in 5 specimens and under US guidance in the remaining 5.  The needles were left in-situ in all specimens and their placement was confirmed fluoroscopically.  In all 5 specimens injected under US guidance, the needle was found to be in the joint, whereas all 5 injected by palpation only were out of the joint, with 1 in the naviculo-cuneiform joint, showing US guidance to significantly increase the accuracy of intra-articular injections in the talo-navicular joint than palpatory method alone.  The authors concluded that US-guided injections not only confirmed correct needle placement, but also delineated any tendon and/or joint pathology simultaneously.  This was a small (n = 5 in the US-guided group) cadaveric study; these preliminary findings need to be validated in well-designed human studies.

Musculoskeletal Ultrasonography

Kane et al (2001) compared ultrasonography (US) with bone scintigraphy in the diagnosis of plantar fasciitis and compared US-guided injection with palpation-guided injection in the management of idiopathic plantar fasciitis.  The authors concluded that US-guided injection was effective in the management of plantar fasciitis but was not more effective than palpation-guided injection.  

Yucel et al (2009) compared the efficacies of scintigraphy-guided (sg), US-guided (ug), and palpation-guided (pg) steroid injections in the treatment of plantar fasciitis.  The authors concluded that the ug, pg, and sg injections were effective in the conservative treatment of plantar fasciitis.  These researchers were of the opinion that steroid injections should be performed, preferably with palpation or US guidance.

Balint et al (2002) compared US with clinical examination in the detection of entheseal abnormality of the lower limb in patients with spondyloarthropathy (SpA).  The authors concluded that most entheseal abnormality in SpA was not detected at clinical examination; and US was better than clinical examination in the detection of entheseal abnormality of the lower limbs in SpA.  These researchers proposed a quantitative US score of lower limb enthesitis; however, further studies are needed to validate it in SpA.

Naredo et al (2004) compared the short-term response to randomized blind injection versus US-guided injection of local corticosteroid in patients with painful shoulder.  The authors concluded that US-guided corticosteroid injections should be indicated, at least, in patients with poor response to previous blind injection to ensure accurate medication placement in order to improve therapeutic effectiveness.  Moreover, these researchers stated that a double-blind study would have been desirable to avoid bias. 

Chen et al (2006) examined the treatment effectiveness between US-guided and blind injection techniques in the treatment of subacromial bursitis.  The authors concluded that US may be used as an adjuvant tool in guiding the needle accurately into the inflamed subacromial bursa.  The US-guided injection technique can result in significant improvement in shoulder abduction range of motion (ROM) as compared with the blind injection technique in treating patients with subacromial bursitis.  

Rutten et al (2007) compared the accuracy of blind injection to that of US-guided injection into the subacromial-sub-deltoid bursa (SSB) for diagnostic purposes (Neer test) or therapeutic purposes (corticosteroid therapy).  The authors concluded that blind injection into the SSB was as reliable as US-guided injection; and thus, could be used in daily routine.  These investigators stated that US-guided injections may offer a useful alternative in difficult cases, such as with changed anatomy post-operatively or when there is no effective clinical outcome. 

Luz et al (2008) compared the effectiveness of blind and US-guided intra-articular (IA) injections in patients with rheumatoid arthritis (RA) with wrist synovitis.  The authors concluded that the findings of this study showed that US did not increase the accuracy of wrist injections when they were performed by an experienced rheumatologist.  Moreover, these investigators stated that further studies are needed to examine the benefit of US-guided interventions for IA injection in deep joints and peri-articular anatomical sites as well as for doctors not so well trained in the blind procedure.

Im et al (2009) examined the feasibility of using real-time high-resolution US to guide an injection needle into the IA space within the knee.  The authors concluded that IA injections via a medial patellar portal using US guidance may raise the accuracy rate in knee joint injections.

Lee et al (2009) examined the clinical effect of US-guided IA injections compared with a blind (unguided) technique for the treatment of adhesive capsulitis.  The authors concluded that US-guided IA injections may offer advantages over a blind technique for the treatment of adhesive capsulitis and may deliver clinical benefits during the first few weeks of treatment.  These researchers stated that the key limitation of this study was the relatively small sample size in each group (n = 21 in the US-guided group, and n= 22 in the blind injection group).  They stated that for more confirmative recognition of the usefulness of the US-guided technique, several similar studies with a larger number of patients in multiple centers or studies with 2 or 3 serial injections of 1 substance under US guidance are needed.

Ucuncu et al (2009) compared the effectiveness of landmark-guided local injections and US-guided injections for shoulder pain.  The authors concluded that the injection of corticosteroids to patients with shoulder pain due to soft tissue disorders under the US guidance may improve therapeutic effectiveness and reduce adverse effects.  These investigators recommended the use of US guidance in local injections, which have a potential to offer a significant rise in clinical effectiveness of this therapy.  The authors stated that the possible placebo effect of expectation being higher in US group was among the limitations in this study.  Another limitation could be that the heterogeneous diagnoses for certain conditions (e.g., biceps tendonitis) that could respond to the corticosteroid injection differently (e.g., acute inflammatory component might be more likely to respond to injections than conditions such as rotator cuff tears or long-standing degenerative joint disease).  But in terms of initial design of this study the main outcome measure was based on shoulder pain and functionality, which were evaluated at baseline and after the procedure.  However, the retrospective evaluation of the files in the groups showed that the clinical varieties were almost evenly distributed among the groups.  The patients were not restricted to use anti-inflammatory medication, and this may be another limitation that could have impact in clinical endpoints and may be the sample size of the study was rather small (n = 30 for each 2 groups) for a more conclusive statement on the topic.

Sibbitt et al (2009) examined if US needle guidance would affect clinical outcomes of IA joint injections.  The authors concluded that US needle guidance significantly improved the performance and outcomes of outpatient IA injections in a clinically significant manner.  Moreover, these researchers stated that future research is needed to examine the effects of US-guided IA procedures on long-term outcomes, functional measures, individual joints, serious complications, and overall healthcare costs.

Wiler et al (2010) examined the success of emergency physicians performing landmark (LM) versus US-guided knee arthrocentesis techniques.  The authors concluded that US-guided knee arthrocentesis technique does NOT improve overall success of obtaining joint fluid aspirate versus the standard LM and palpation technique.  An US-guided approach does not result in more pain for the patient, takes no additional time to perform and, at least for novice physicians, resulted in more fluid aspiration and greater novice provider confidence with the procedure.  These researchers stated that further studies with more subjects and standardization of anesthetic quantity are needed to validate these findings.

Cunnington et al (2010) examined if US guidance would improve the accuracy and clinical outcome of joint injections as compared with clinical examination (CE) guidance in patients with inflammatory arthritis.  The authors concluded that US guidance significantly improved the accuracy of joint injection, allowing a trainee to rapidly achieve higher accuracy than more experienced rheumatologists.  US guidance did not improve the short-term outcome of joint injection.

In a prospective, single-blind, cadaveric study, Finnoff et al (2010) compared the accuracy of US-guided versus unguided pes anserinus bursa injections.  The authors concluded that clinicians should consider using US-guidance for diagnostic or therapeutic pes anserinus bursa injections when indicated.

Hartung et al (2010) examined the clinical outcome of US-guided corticosteroid sacroiliac joint (SIJ) injections in relation to the accuracy of the injection.  The authors concluded that IA SIJ injections remain technically challenging despite US guidance.  Moreover, these researchers stated that peri-articular deposition of triamcinolone appeared sufficient for pain and symptom control in patients suffering from active sacroiliitis.

In a prospective, laboratory study,  Peck et al (2010) described a technique for US-guided acromioclavicular joint (ACJ) injections and compared its accuracy to palpation-guided injections in a cadaveric model.  The authors concluded that the findings of this cadaveric study suggested that US guidance could be used to inject the ACJ with a high degree of accuracy, and should be considered superior to palpation guidance.  Moreover, these researchers stated that whether similar results would be realized in a larger, more heterogeneous clinical population warrants further study.  They noted that this study had several drawbacks including this study were performed on un-embalmed cadavers, small sample size (only 20 total injections were carried out), a single operator conducted all injections in the current study, and the present study was limited to the lateral-to-medial approach to ACJ injection.

Sibbitt et al (2011) examined if US needle guidance would affect the outcomes of IA injection for inflammatory arthritis.  The authors concluded that US needle guidance improved the performance, clinical outcomes, and cost-effectiveness of IA injections for inflammatory arthritis.  These investigators stated that there are certain limitations to these cost-effectiveness analyses.  First, the analysis concerning inflammatory arthritis does not apply to the osteoarthritic joint as the synovial target.  Both synovial fluid and hypertrophied synovial tissue mass in the inflammatory or rheumatoid joint are much larger than the synovial target in the non-effusive osteoarthritic joints; therefore, palpation-guided injections to treat inflammatory arthritis are more likely to be consistently intra-articular or intra-synovial.  This would have the effect of converging the palpation and image-guided groups.  In addition, inflammatory arthritis due to gout, calcium pyrophosphate deposition disease, or other forms of acute inflammatory arthritis could not be addressed because this study specifically excluded these other forms of arthritis and included only chronic autoimmune inflammatory arthritis.  The increased responder rate with US guidance may be of societal value beyond costs to a 3rd-party payer (better quality of life, less lost work, and fewer disability payments); therefore, since outcomes are better, there may be a justification for using US guidance for injection of inflammatory arthritis regardless of increased procedural costs.

Sibbitt et al (2012) compared arthrocentesis of the effusive knee followed by corticosteroid injection performed by the conventional anatomic landmark palpation-guided technique to the same procedure performed with US needle guidance.  The authors concluded that US-guided arthrocentesis and injection of the knee were superior to anatomic landmark palpation-guided arthrocentesis, resulting in significantly less procedural pain, improved arthrocentesis success, greater synovial fluid yield, more complete joint decompression, and improved clinical outcomes. 

Scillia et al (2015) examined the accuracy of in-vivo ACJ injections without fluoroscopic (FL) guidance and examined if patient demographics affected the accuracy of injections (total of 41 ACJ injections).  The authors encouraged the use of image guidance for corticosteroid treatment of the ACJ.  Level of Evidence = IV.

In a prospective, randomized, controlled trial, Soneji et al (2016) compared the accuracy and effectiveness of US and FL guidance for SIJ injections in patients with chronic moderate-to-severe LBP secondary to SIJ arthritis (n = 40).  The authors concluded that US-guided SIJ injection with FL confirmation had similar accuracy and effectiveness to FL alone for SIJ injections in patients with chronic LBP secondary to SIJ arthritis.  These researchers stated that the findings of this study did not identify a difference in accuracy, effectiveness, or overall patient satisfaction between these 2 image-guided techniques for SIJ injection; however, future studies are needed for confirmation.

In a controlled, laboratory study, Perry et al (2016) examined the accuracy of US-guided SIJ injections using a cadaveric model.  The authors concluded that US allowed IA injection in 88.2 % of joints in this cadaveric study.  These investigators noted that US does not expose the patient to radiation, as observed with FL guidance, which is currently the gold standard for this injection.  Furthermore, US may allow visualization of extra-articular spread when caused by extra-articular needle placement, which can allow for re-direction of the needle to achieve IA injection.  Moreover, these researchers stated that further studies are needed to determine the diagnostic value of this procedure.  Level of Evidence = IV.

In a cadaveric study, Stelzer et al (2019) determined the success rate of FL-guided and US-guided IA SIJ injection.  The authors concluded that FL guidance showed a higher success rate of IA SIJ injection than US-guided IA SIJ injection.

De Luigi et al (2019) examined the accuracy of US-guided needle placement for SIJ injections (n = 50 patients).  The authors concluded that US-guided injection of the SIJ was successful and accurate upon confirmation of FL arthrogram and should be used as an imaging modality for needle guidance. 

The article by Schneider et al (2020) was a “Letter to the Editor” regarding the study by De Luigi et al (2019).  Schneider and colleagues stated that “[W]e suggest that the authors consider tempering their concluding recommendation that US “should be utilized as an imaging modality for needle guidance” in the context of SIJ injections.  We agree with the authors that given the potential advantages of US guidance; more research is warranted”.

In a prospective study, Ali et al (2021) compared the accuracy and performance of FL-guided, US-guided, and non-image-guided IA contrast injection via an anterior approach for performing shoulder MR arthrography (MRA).  The authors concluded that imaging-guided injections are more accurate and tolerable than non-image-guided and should be considered to confirm IA needle position, hence adequate capsular distension, and good diagnostic quality of shoulder MRA.  These investigators stated that US guidance was a less painful, rapid, and safe alternative to the FL approach.  The authors stated that this trial gad several drawbacks.  First, this was not a strict direct comparison between the 3 contrast injection techniques, as each technique was applied to a separate group of patients.  Second, the experience of the injector might have played a role in the care provided to patients and consequently in the results, regarding the number of attempts to puncture the joint, procedure time, pain experienced by the patient, rate of contrast extravasation, and finally image interpretation. Third, the baseline VAS pain score was not examined in this study; thus, pre-existing patients’ pain might affect the evaluation of the pain score during and after injection.  In addition, despite the instruction given to the patients, no confirmed documents could be obtained regarding the patients’ use of analgesics 24 hours before or after the injections.  Furthermore, the patient interpretation of pain levels is still a subjective matter, with individual variations.  Fifth, only patients who met the inclusion criteria and accepted participation, as well as the result of the randomization process, were included in the study, and this may have led to a selection bias.  Lastly, this study had a small sample size, which necessitates confirmation of these findings by studies carried out on a larger group of patients.  Evidence Level = II.

Chean et al (2022) examined if the accuracy of placement of US-guided corticosteroid injections for subacromial pain (impingement) syndrome (SAPS) would influence pain and function outcomes.  The authors concluded that the accuracy of injection placement in SAPS did not influence pain and function, suggesting that improvements in patients' outcomes using subacromial corticosteroid injections can be achieved without US guidance.

In a retrospective analysis, Beard et al (2023) presented a standardized technique of US-guided injection into the glenohumeral joint utilizing the rotator cuff interval (RCI) in MRI arthrography (MRA) and to report one medical group's experience with the technique.  The authors concluded that accessing the RCI under US guidance was a very successful technique for injection within the glenohumeral joint.  Moreover, these researchers stated that the main drawback of this study was its retrospective nature, which prevented inclusion of additional data points of potential interest.  These investigators stated that a prospective study in which this technique is compared to alternative approaches could be helpful, especially in measures of patient discomfort, clinical effectiveness, or further investigation into quality of imaging.

Occipital Nerve Block

In a prospective, randomized, placebo-controlled, double-blind pilot trial, Palamar et al (2015) compared the effectiveness of US-guided greater occipital nerve block (GONB) using bupivacaine 0.5 % and placebo on clinical improvement in 23 patients with refractory migraine without aura (MWOA).  Patients were randomly assigned to receive either GONB with local anesthetic (bupivacaine 0.5 % 1.5 ml) or GON injection with normal saline (0.9 % 1.5 ml).  Ultrasound-guided GONB was carried out to more accurately locate the nerve.  All procedures were performed using a 7- to 13-MHz high-resolution linear US transducer.  The treatment group was comprised of 11 patients and the placebo group was comprised of 12 patients.  The primary outcome measure was the change in the headache severity score during the 1-month post-intervention period.  Headache severity was assessed with a VAS from 0 (no pain) to 10 (intense pain).  In both groups, a decrease in headache intensity on the injection side was observed during the first post-injection week and continued until the second week.  After the second week, the improvement continued in the treatment group, and the VAS score reached 0.97 at the end of the fourth week.  In the placebo group after the second week, the VAS values increased again and nearly reached the pre-injection levels.  The decrease in the monthly average pain intensity score on the injected side was statistically significant in the treatment group (p = 0.003), but not in the placebo group (p = 0.110).  No statistically significant difference in the monthly average pain intensity score was observed on the un-injected side in either group (treatment group, p = 0.994; placebo group, p = 0.987).  No serious side effect was observed after the treatment in either group.  The authors concluded that US-guided GONB with bupivacaine for the treatment of migraine patients was a safe, simple, and effective technique without severe adverse effects.  To increase the effectiveness of the injection, and to implement the isolated GONB, ultrasonography guidance could be suggested.  The drawbacks of this pilot study include small sample size (n = 11 in the US-guided group) and short follow-up duration (1 month).

In a prospective open-label stud, Pingree et al (2017) examined the analgesic effects of an US-guided GONB at the level of C2, as the nerve courses superficially to the obliquus capitis inferior muscle.  A total of 14 injections with US-guided GONBs at the level of C2 were performed on patients with a diagnosis of occipital neuralgia or cervicogenic headache; NRS pain scores were recorded pre-injection and at 30 mins, 2 weeks, and 4 weeks after injection.  Anesthesia in the GON distribution was achieved for 86 % of patients at 30 mins post-injection.  Compared with baseline, NRS scores decreased by a mean of 3.78 at 30 mins (p < 0.001), 2.64 at 2 weeks (p = 0.006), and 2.21 at 4 weeks (p = 0.01).  There were no significant AEs reported during the study period.  The authors concluded that their study demonstrated successful blockade of the GON at the level of C2 using a novel US-guided technique, and that significant reductions in pain scores were observed over the 4-week study period without AEs.  The observations from this study provided preliminary data for future randomized trials involving patients with occipital neuralgia and cervicogenic headache.

Paravertebral Nerve Block during Rib Plate Removal/for Post-Operative Pain Management

Riain et al (2010) developed a technique for US-guided para-vertebral block (PVB), which was subsequently applied in the clinical setting.  An initial cadaver study was used to develop a technique that was used in the clinical setting on patients undergoing breast cancer surgery.  Paravertebral catheters were correctly placed in the cadaveric trial in 8 of 10 attempts.  In the clinical study, all blocked patients (n = 9) had evidence of thoracic wall sensory block and analgesia post-operatively.  The authors concluded that determined by anatomical dissection, they had described the US features of the thoracic para-vertebral space and performed clinically successful US-guided PVB.  These researchers stated that obvious drawbacks in both the anatomical and clinical elements of this study were the limited numbers studied and the lack of a control group.  They stated that further work is needed in a blinded comparative study of the traditional loss-of-resistance technique with US-guided block.

Terkawi et al (2015) noted that while most studies of thoracic PVB (TPVB) for breast surgery showed benefit, their effect on post-operative pain intensity, opioid consumption, and prevention of chronic post-surgical pain varied substantially across studies.  Variability may result from use of different drugs and techniques.  In a mixed-effects meta-analysis, these investigators examined the use of TPVB in breast surgery; and determined which method(s) would provide optimal safety and effectiveness.  They carried out a systematic review of randomized trials comparing TPVB to no intervention using random-effects models.  To evaluate the contributions of various techniques, clinical approaches were included as moderators in mixed-effects models.  A total of 24 RCTs with 1,822 patients were included.  Use of TPVB decreased post-operative pain scores at rest and movement at the first 2, 24, 48, and 72 hours.  TPVB modestly decreased intra-operative and post-operative opioid consumption, reduced nausea and vomiting, and shortened hospitalization, but to a probably clinically irrelevant degree.  Blocks also appeared to reduce the incidence of chronic post-surgical pain at 6 months.  Adding fentanyl to the TPVB improved pain at rest (at 24, 48, and 72 hours) and movement (at 24 and 72 hours).  Multi-level blocks provided better post-operative pain control, but only during movement (at 2, 48, and 72 hours).  Fewer procedural complications (especially hypotension, epidural spread, and Horner's syndrome) occurred when anatomical landmarks were supplemented with US guidance.  The authors concluded that TPVB reduced post-operative pain and opioid consumption; and had a limited beneficial effect on the quality of recovery.  From all the techniques that were evaluated, only the addition of fentanyl, and performing multi-level blocks were associated with improved acute analgesia.  TPVB may reduce chronic post-surgical pain at 6 months.  These researchers stated that the main drawback of this study was that the number of studies available was limited in the meta-analytic model of incidence of chronic post-surgical pain.  For example, 6 studies provided information on post-operative pain at 48 and 72 hours, 6 examined the hospital LOS, and 4 reported incidences of chronic post-surgical pain.  As such, it was premature to draw conclusions regarding the effect of TPVB on these specific outcomes based on the current findings, and caution is needed when interpreting these findings.  Moreover, these investigators noted that all studies included in this analysis used placebo control groups.  This was an appropriate scientific approach; however, differences between the block and controls groups would likely have been even smaller had the control groups been given multi-modal analgesia.

Saleh et al (2018) noted that surgery for aortic coarctation requires special care during anesthesia due to severe pain during the lateral thoracotomy incision, intra-operative hemodynamic instability, and the need for large doses of intra- and post-operative analgesics and vasodilators.  Furthermore, the post-operative care of patients is very important.  In a prospective, randomized, controlled, double-blinded study, these researchers compared US-guided PVB performed using bupivacaine alone and bupivacaine with dexamethasone in terms of the intra- and post-operative analgesic requirements and hemodynamics, post-operative complications and ICU stay.  A total of 50 patients aged 4 to 12 months scheduled for aortic coarctation surgery were randomly divided into 2 equal groups (n = 25).  Patients in group D (dexamethasone) received 0.5 mg/kg bupivacaine 0.25 % mixed with 0.1 mg/kg dexamethasone diluted with isotonic saline and those in group C (control) received 0.5 mg/kg bupivacaine 0.25 % diluted with isotonic saline (total volume 15 ml in each group).  Intra-operative fentanyl consumption and hemodynamics (HR, arterial BP [ABP]) at baseline, 1 min after induction, at skin incision, after 30 mins, after clamping, after de-clamping and at the end of the surgery were recorded, along with the objective pain score (OPS) immediately post-operatively and at 4 hours, 8 hours, 12 hours and 24 hours post-operatively and the time to the 1st request for pethidine.  The intra- and post-operative vasodilator doses, time-to-extubation, ICU stay duration and post-operative complications were also recorded.  The post-operative OPS was significantly lower at 12 and 24 hours in group D than in group C.  The time to the 1st request for analgesia was significantly longer in group D than in group C (3.9 ± 2.23 hours versus 8.6 ± 0.69 hours).  Additionally, the time-to-extubation was significantly shorter in group D.  The authors concluded that the use of dexamethasone as an adjuvant in US-guided PVB in pediatric patients undergoing surgery for aortic coarctation increased the duration of post-operative analgesia with a prolonged time to the 1st request for analgesics.  It was also associated with a decreased incidence of post-operative complications.  These researchers stated that this study was limited in that only pediatric patients undergoing one type of surgery were included.  They recommended further investigation in patients of different ages undergoing various types of surgery, especially chest surgery; they also recommend catheterization for continuous anesthesia and analgesia.

Percutaneous Tenotomy of the Gluteus Medius Tendon for the Treatment of Hip Tendinopathy

Jacobson et al (2015) noted that percutaneous US-guided needle fenestration has been used to treat tendinopathy of the elbow, knee, and ankle with promising results.  These researchers examined the clinical outcome of US-guided fenestration of tendons about the hip and pelvis.  After Institutional Review Board (IRB) approval, a retrospective search of imaging reports from January 1, 2005, to June 30, 2011, was completed to identify patients treated with US-guided tendon fenestration about the hip or pelvis.  Subsequent clinic notes were retrospectively reviewed to examine if the patient showed marked improvement, some improvement, no change, or worsening symptoms.  The study group consisted of 22 tendons in 21 patients with an average age of 55.8 years (range of 26.7 to 77.0 years).  The treated tendons included 11 gluteus medius (9 tendinosis and 2 partial tears), 2 gluteus minimus (both tendinosis), 8 hamstring (6 tendinosis and 2 partial tears), and 1 tensor fascia latae (tendinosis).  The average interval to clinical follow-up was 70 days (range of 7 to 813 days).  There was marked improvement in 45.5 % (10 of 22), some improvement in 36.4 % (8 of 22), no change in symptoms in 9.1 % (2 of 22), and worsening symptoms in 9.1 % (2 of 22).  There were no patient variables (age, chronicity of symptoms, sex, tendon, tendinosis versus tear, prior physical therapy, and prior corticosteroid injection) that were significantly different between patients who improved and those who did not.  There were no cases of a subsequent tendon tear or infection.  The authors concluded that clinical follow-up following US-guided fenestration of the gluteus medius, gluteus minimus, proximal hamstring, and tensor fascia latae tendons showed that 82 % of patients had improvement in their symptoms.  These researchers stated that further studies are needed to determine the long‐term effects of US‐guided tendon fenestration and to compare fenestration to other percutaneous tendon treatments.

The authors stated that this study had several drawbacks.  Given the retrospective nature, they had to rely on dictated follow‐up visit notes from the referring clinicians to determine whether symptoms had improved.  A prospective trial would allow more specific and objective assessment of patient symptoms at uniform intervals.  In addition, imaging follow‐up was not obtained, so it was unclear whether changes on US imaging occurred after the tendon fenestration and whether such changes correlated with patient outcomes.  Last, these investigators did not compare tendon fenestration to other treatments; a blinded randomized controlled trial (RCT) would be important to provide such information.

Jacobson et al (2016) compared US-guided percutaneous tendon fenestration to platelet-rich plasma (PRP) injection for treatment of greater trochanteric pain syndrome.  After IRB approval was obtained, patients with symptoms of greater trochanteric pain syndrome and US findings of gluteal tendinosis or a partial tear (less than 50 % depth) were blinded and treated with US-guided fenestration or autologous PRP injection of the abnormal tendon.  Pain scores were recorded at baseline, week 1, and week 2 after treatment.  Retrospective clinic record review assessed patient symptoms.  The study group consisted of 30 patients (24 female), of whom 50 % were treated with fenestration and 50 % were treated with PRP.  The gluteus medius was treated in 73 % and 67 % in the fenestration and PRP groups, respectively.  Tendinosis was present in all patients.  In the fenestration group, mean pain scores were 32.4 at baseline, 16.8 at time point 1, and 15.2 at time point 2.  In the PRP group, mean pain scores were 31.4 at baseline, 25.5 at time point 1, and 19.4 at time point 2.  Retrospective follow-up showed significant pain score improvement from baseline to time points 1 and 2 (p < 0.0001); but no difference between treatment groups (p = 0.1623).  There was 71 % and 79 % improvement at 92 days (mean) in the fenestration and PRP groups, respectively, with no significant difference between the treatments (p > 0.99).  The authors concluded that the findings of this study showed that both US-guided tendon fenestration and PRP injection were effective for treatment of gluteal tendinosis, showing symptom improvement in both treatment groups.  These researchers stated that future prospective RCTs with more long‐term and objective clinical assessment are needed to determine the clinical value of US-guided percutaneous tendon fenestration for the treatment of greater trochanteric pain syndrome.

The authors stated that this study had several drawbacks.  First, long‐term symptom improvement was limited by retrospective assessment, with a somewhat short interval and a wide range of follow‐up durations.  The sample size was limited (n = 15 for the US-guided percutaneous tendon fenestration group) because of budgetary constraints, and it remained possible that the effect size was not large enough to detect a difference between the treatment groups.  Nonetheless, the results showed symptom improvement in the short-term and months after treatment.  The limited retrospective follow‐up could be interpreted as a potential positive outcome if asymptomatic patients did not seek further treatment for their greater trochanter symptoms.  Another drawback was that the PRP samples were not individually assessed for platelet count; however, the PRP preparation kit used was commercially available and was reported to concentrate platelets to 4 to 6 times that in whole blood.  An additional drawback was that all patients had tendinosis, so it was unclear whether patients with tendon tears would respond in a different manner.  One last limitation was that patient care after treatment was not controlled, which may affect longer‐term clinical outcomes.

Perineal Nerve Block for Spastic Pelvic Floor Syndrome and Pudendal Neuralgia

Rofaeel et al (2008) noted that compared with conventional fluoroscopic-guided pudendal nerve block, US has potential advantages for visualizing anatomical landmarks such as the internal pudendal artery and nerve, the sacrospinous and sacrotuberous ligaments, and local anesthetic spread.  In a case-series study, these researchers examined the clinical utility of performing pudendal nerve block under real-time US guidance.  A total of 17 patients were studied.  With the patient lying prone, a 2- to 5-MHz curved array US probe was placed at the level of the ischial spine to capture the transverse view of the ischial spine, the sacrospinous and sacrotuberous ligaments (SSL and STL), the internal pudendal artery (confirmed with color Doppler), and the pudendal nerve.  A 22-G needle was advanced under real-time US guidance to reach the pudendal nerve in the plane between the STL and SSL.  Following confirmation of spread of dextrose 5 % solution in the inter-ligamentous plane, a mixture of 5-ml 0.25 % bupivacaine with 1:200,000 epinephrine and 40 mg Depo-Medrol (Pharmacia & Upjohn, Kalamazoo, MI) was injected.  Assessment included the ease of identification of anatomical structures and local anesthetic spread with US, and the degree of sensory block in the perineum.  The ischial spine, SSL, STL, internal pudendal artery, and pudendal nerve were easily identifiable with US in the majority of patients.  Local anesthetic (LA) spread was observed as a hypoechoic collection around the nerve and expanding between the STL and SSL.  All patients developed perineal sensory block following the procedure.  The authors concluded that pudendal nerve block at the ischial spine level could be reliably performed under real-time US guidance.  Moreover, these researchers stated that while these findings demonstrated favorable clinical outcome, future studies are needed to further examine the evidence for the clinical use of US-guided pudendal nerve block compared with other techniques.

The authors stated that there were a few drawbacks with this case-series study, which examined the feasibility of performing pudendal nerve block under real-time US guidance and was not intended to compare the improvement in outcome with that of a fluoroscopic-guided technique.  The assessment of the visualization of the landmarks was performed by authors not blind to the procedure.  This might have resulted in bias of assessment; however, all procedures were successfully performed without further fluoroscopic guidance.  Nerve stimulation was set as an a priori criterion for successful block, similar to other peripheral nerve block techniques.  However, the authors’ experience showed that it was not a reliable confirmation test, possibly because of the size of the nerve at the inter-ligamentous plane.  The confirmation of the pudendal nerve therefore relies on the visualization of the nerve and surrounding structures, and on the spread of the solution in the inter-ligamentous plane.

Gaudet-Ferrand et al (2018) stated that trans-perineal pudendal nerve block guided by nerve stimulator is used in pediatric anesthesia as an alternative to caudal analgesia in perineal surgery.  The risk of rectal puncture or intravascular injection is inherent to this blinded technique.  These researchers described a new technique of trans-perineal pudendal nerve block, with US guidance, to improve safety of the technique.  The 1st objective of this study was to describe this new technique and to test its feasibility; and the 2nd objective was to evaluate intra-operative effectiveness and post-operative pain control.  After parental and children consented, this prospective descriptive study included children aged 1 to 15 years, ASA status I to III, scheduled for general anesthesia associated with bilateral pudendal nerve block for an elective perineal surgery.  After standardized general anesthesia, the anesthesiologist performed pudendal nerve block under US guidance with "out of plane" approach and evaluated the visualization of anatomical structures (ischial tuberosity, rectum, and pudendal artery), of the needle and of the local anesthetic spread.  Pudendal nerve block failure was defined as an increase in mean arterial blood pressure or heart rate more than 20 % compared to baseline values after surgical incision.  In the post-operative period, the need for rescue analgesia was noted.  During the study period, 120 blocks were performed in 60 patients, including 59 boys.  Quality of the US image was good in 81 % of blocks, with easy visualization of ischium and rectum in more than 95 % of cases.  Localization of the tip of the needle was possible for all pudendal nerve blocks, directly or indirectly.  The spread of LA was observed in 79 % of cases.  The block was effective in 88 % of cases.  The authors concluded that the new technique of US-guided pudendal nerve block appeared to be easy to perform with a good success rate, and probably improved safety of the puncture and of the injection by real-time visualization of anatomical structures and LA spread.  Moreover, these researchers stated that benefits of the technique regarding its safety and effectiveness, compared with blinded techniques, must be further evaluated in randomized studies.

The authors stated that this study had several drawbacks.  First, the spread of LA in the ischiorectal fossa and its potential effect on success of pudendal nerve block were not evaluated, not allowing to know if an injection too deep entailed a failure of the block.  These investigators stated that the results concerning post-operative pain should be the subject of further investigations.  Second, effectiveness of the technique was not the primary objective, and pain evaluation was based only on analgesic consumption, and not on pain scores.  The use of post-emergence delirium score would be necessary to better evaluate pain level in PACU.  Third, the optimal volume of LA in the ischiorectal fossa remains to be determined in children.  Fourth, the study did not have any control group, difficult to determine in view of the diversity of surgical procedures; thus, the effectiveness of this new US-guided technique has to be demonstrated in randomized studies.

Peritendon Injection for the Treatment of Achilles Tendinopathy

Chimenti et al (2020) stated that peripherally directed treatments (targeted exercise, surgery) can reduce, but not fully eliminate, pain for up to 40 % of patients with Achilles tendinopathy.  In a mechanistic clinical trial, these researchers identified indicators of altered central processing in patients with Achilles tendinopathy compared to controls; and determined which indicators of altered central processing would persist after a local anesthetic injection in patients with Achilles tendinopathy.  A total of 46 adults (23 with chronic Achilles tendinopathy, 23 matched controls) repeated a movement-evoked pain rating, motor performance assessment, pain psychology questionnaires, and quantitative sensory testing (QST).  Participants with Achilles tendinopathy received a local anesthetic injection before repeat testing and controls did not.  Mixed-effects analyses of variance examined the effects of group, time, and group by time.  The Achilles tendinopathy group had movement-evoked pain, motor dysfunction, and higher pain psychological factors (pain catastrophizing, kinesiophobia) compared to controls (p < 0.05).  The Achilles tendinopathy group did not have indicators of nociplastic pain with QST (p > 0.05).  In those with Achilles tendinopathy, local anesthetic injection eliminated pain and normalized the observed deficits in heel-raise performance and pain catastrophizing (group-by-time effect, p < 0.01), but not in kinesiophobia (p = 0.45).  Injection did not affect measures of nociplastic pain (p > 0.05).  The authors concluded that individuals with Achilles tendinopathy had elevated pain psychological factors and motor dysfunction but no signs of nociplastic pain with QST.  Removal of nociceptive input normalized movement-evoked pain and some indicators of altered central processing (motor dysfunction, pain catastrophizing), but not kinesiophobia.  This was a relatively small (n = 23 in the Achilles tendinopathy group) study, and it did not address the use of ultrasound guidance for anesthetic injections.

An UpToDate review on “Overview of the management of overuse (persistent) tendinopathy” (Scott and Purdam, 2021) does not mention local anesthetics injection as a management / therapeutic option.

Furthermore, an UpToDate review on “Achilles tendinopathy and tendon rupture” (Maughan and Boggess, 2021) states that “High-volume injection -- This intervention (sometimes referred to as the Brisement procedure) involves injecting a high volume of fluid (typically consisting of isotonic saline, glucocorticoid, and local anesthetic), under ultrasound guidance, into the paratenon with the intent of reducing pain by disrupting abnormal blood vessels and peripheral nerves.  Preliminary studies suggest possible benefit in patients with Achilles tendinopathy, including earlier return to sport, but further study is needed”.

Peroneal Tendon Sheath Injection

Muir et al (2011) described an ultrasound (US)-guided peroneal tendon sheath (PTS) injection technique and compared the accuracy of US-guided versus palpation-guided PTS injections in a cadaveric model.  A total of 20 cadaveric lower limbs were injected with and without US guidance, using a different color of liquid latex for each injection technique.  The injections were carried out by a single investigator in a randomized order.  Cadaveric specimens were dissected 1 week later by a “blinded” investigator who graded injection accuracy on a 3-point scale (1 = accurate; 2 = partially accurate; and 3 = inaccurate); US-guided injections were 100 % (20 of 20) accurate whereas palpation-guided injections were 60 % (12 of 20) accurate (p = 0.008); 6 palpation-guided injections were partially accurate, and 2 were inaccurate; 2 of the partially accurate and both of the inaccurate injections were intra-tendinous.  The authors concluded that in a cadaveric model, US-guided PTS injections were significantly more accurate than palpation-guided injections.  When performing PTS injections, clinicians should consider US guidance to improve injection accuracy and minimize potential complications such as intra-tendinous injection.  This was a small, cadaveric study; its findings need to be validated in well-designed human studies using human subjects

Platelet-Rich Plasma Injections in the Treatment of Hip Osteoarthritis

Ali and colleagues (2018) examined if US-guided platelet-rich plasma (PRP) injection has any role in improving clinical outcomes in patients with hip osteoarthritis (OA).  These investigators carried out a search of the National Institute for Health and Care Excellence database using the Healthcare Databases Advanced Search tool.  The PubMed database was also utilized to search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index of Nursing and Allied Health and Allied and Complimentary Medicine databases.  The Preferred Reporting Items for Systematic Review and Meta-Analysis methodology guidance was employed and a quality assessment was performed using the Jadad score.  A total of 3 randomized clinical trials met the inclusion criteria and were included for analysis.  All 3 studies were of good quality based on the Jadad score.  A total of 115 patients out of 254 received PRP injections under US guidance.  The PRP recipient group included 61 men and 54 women aged 53 to 71 years.  Outcome scores showed an improvement of symptoms and function maintained up to 12 months following PRP injection.  The authors concluded that available evidence indicated that intra-articular PRP injections of the hip, performed under US guidance to treat hip OA, were well-tolerated and potentially effective in delivering long-term and clinically significant pain reduction and functional improvement in patients with hip OA.  Moreover, these researchers stated that larger future trials including a placebo group are needed to further evaluate these promising findings.

Posterior Tibial Nerve Block for Plantar Fasciitis

Redborg et al (2009) noted that the tibial nerve provides the majority of sensation to the foot.  Although multiple techniques have been described, there exists little evidence-based medicine evaluating different techniques for blocking the tibial nerve at the ankle.  These researchers hypothesized that an ultrasound (US)-guided tibial nerve block at the ankle would prove more successful than a conventional approach based on surface landmarks.  A total of 18 healthy volunteers were prospectively randomized into this controlled and blinded study.  Each subject was placed prone, and 1 ankle was randomly assigned to receive either an US-guided tibial nerve block (group US) or a traditional landmark-based tibial nerve block (group LM).  The subject's other ankle then received the alternate approach.  All blocks were performed with 5-ml 3 % chloroprocaine.  These investigators evaluated sensory and motor blocks.  A successful block was defined as complete loss of sensation to both ice and pin-prick at 5 cutaneous sites.  Secondary outcome variables included performance times, number of needle passes, participant satisfaction, and presence of any complications.  At 30 mins, the block was complete in 72 % of participants in the US group as compared with 22 % in the LM group.  At all times, the proportion of complete blocks was higher in the US group.  Ultrasound-guided blocks took longer on average to perform than traditional blocks (159 versus 79 secs; p < 0.001).  There were more needle re-directs in the US group, with 8 subjects requiring 3 or more re-directs versus 0 in the LM group.  Subjects preferred the US block 78 % of the time (95 % confidence interval [CI]: 52 % to 95 %).  The authors concluded that in healthy subjects, US guidance resulted in a more successful tibial nerve block at the ankle than did a traditional approach using surface landmarks.  This was a small study (n = 18) carried out on healthy volunteers.

Shah et al (2020) stated that the use of US for peripheral nerve blocks has proven extremely useful for improving the accuracy and efficacy of many regional anesthetic techniques.  There remain a few nerve blocks that have lagged behind in employing the assistance of US consistently, one of which is the ankle block.  This block is commonly utilized for either surgical anesthesia or post-operative analgesia for a variety of foot and ankle procedures.  These researchers compared the accuracy of traditional anatomical landmark-guided technique with an US-guided approach for ankle block by assessing the spread of injectate along the posterior tibial nerve (PTN) in cadaver models.  A total of 10 below-knee cadaver specimens were used for this study; 5 were randomly chosen to undergo anatomical landmark-guided PTN blocks, and 5 were selected for US-guided PTN blocks.  The anatomical landmark technique was performed by identifying the medial malleolus and Achilles tendon and inserting the needle (4 cm long, 21-G Braun Stimuplex) at the mid-point of the 2 structures, aiming toward the medial malleolus and advancing until bone was contacted.  The US technique was performed with a linear probe identifying the medial malleolus and the PTN, with the needle subsequently advanced in-plane with a posterior to anterior trajectory until the tip was adjacent to the nerve.  Each specimen was injected with 2-ml of acrylic dye.  All the specimens were dissected following injection to determine which nerves had been successfully coated with dye.  The PTN was successfully coated with dye in all 5 (100 %) US-guided blocks.  In the anatomical landmark group, 2 (40 %) PTN were successfully coated with dye.  Of the 3 unsuccessful attempts, 2 specimens were noted to have dye injected posterior to the PTN; dye was injected into the flexor digitorum longus tendon in 1.  The authors concluded that the base of evidence has dramatically increased in recent years in support of the use of US in regional anesthesia.  This study substantiated the superiority of US guidance for ankle block by demonstrating a 100 % success rate of delivering a simulated nerve block to the correct anatomic location. 

Furthermore, an UpToDate on “Plantar fasciitis” (Buchbinder, 2021) does not mention the use of tibial nerve block as a therapeutic option for plantar fasciitis.

Pre-Patellar Bursa Injection

An UpToDate review on “Plica syndrome” (Gregory, 2022) states that “The suprapatellar plica lies between the suprapatellar bursa and the knee joint.  Incidence of normal plica in arthroscopically operated knees approaches 87 to 91 % … US identifies swelling in the pes bursa when imaging is used”.  Moreover, this UTD review does not mention the use of US guidance for injection into patellar bursa.

Radial Nerve Block for Post-Operative Pain Management

Henshaw et al (2016) noted that although there are many potentially effective therapeutic options for complex regional pain syndrome (CRPS), no definitive treatment exists; thus, patients often exhaust both medical and surgical therapeutic options trying to find relief for their symptoms.  As pain control and restoration of physical movement are primary therapeutic objectives, strategies that include regional anesthesia techniques are commonly used, but potentially under-utilized, therapeutic modalities.  In a single-case study, these researchers presented the findings of a patient with refractory CRPS who had significant improvement in both pain control and the ability to tolerate intensive PT following the placement of a superficial radial nerve (SRN) catheter and an infusion of LA for 6 days as part of a multi-modal analgesic regimen.  This approach also assisted in the decision-making process related to future therapeutic options.  Although the use of regional anesthesia and peri-neural infusions of LA have previously been described as viable therapeutic options for CRPS, this case report represented the first known use of a SRN catheter for treating CRPS as well as the first description of a technique for placing a SRN catheter using US guidance.

Furthermore, an UpToDate review on “Upper extremity nerve blocks: Techniques” (Jeng and Rosenblatt, 2022) states that “Radial nerve block -- The radial nerve emerges between the brachioradialis tendon and the radius just proximal to the styloid process.  The radial nerve can be blocked anatomically or with ultrasound guidance.  Moreover, the “Summary and Recommendations” section this UTD review notes that “The ulnar, median, or radial nerves can be blocked at the level of the forearm for surgeries of the hand or fingers”.  It does not mention US guidance for radial nerve block.

Semimembranosus Tendon Insertion Injection

In a pilot study, Dallaudiere et al (2014) examined the potential therapeutic effect of intra-tendinous injection of PRP under US guidance for the treatment of tendon tears and tendinosis with long-term follow-up.  The trial included 408 consecutive patients referred for treatment by PRP injection of tendinopathy in the upper (medial and lateral epicondylar tendons) and the lower (patellar, Achilles, hamstring and adductor longus, and peroneal tendons) limb who received a single intra-tendinous injection of PRP under US guidance.  Clinical and US data were retrospectively collected for each anatomic compartment for upper and lower limbs before treatment (baseline) and 6 weeks after treatment.  Late clinical data without US were collected until 32 months after the procedure (mean of 20.2 months).  The McNemar test and regression model were used to compare clinical and US data.  QuickDASH score, WOMAC score, and residual US size of lesions were significantly lower after intra-tendinous injection of PRP under US guidance at 6 weeks and during long-term follow-up compared with baseline (p < 0.001 in upper and lower limb) independent of age, gender, and type of tendinopathy (p > 0.29).  No clinical complication was reported during follow-up.  The authors concluded that intra-tendinous injection of PRP under US guidance appeared to allow rapid tendon healing and was well-tolerated.  This was a retrospective pilot study; its findings need to be validated by well-designed studies.  Moreover, this study did not address semimembranosus tendon insertion injection.

Furthermore, an UpToDate review on “Hamstring muscle and tendon injuries” (Fields et al, 2022) does not mention US guidance as a management / therapeutic tool.

Subacromial Bursitis Injection

Lee et al (2011) noted that subacromial steroid injections are used as a treatment for subacromial bursitis (SB) or shoulder impingement syndrome (SIS).  However, the steroid effect is relatively restricted to the short-term and repeated injections are frequently required, which contributes to unwanted side effects.  As an alternative, botulinum toxin (BT) has recently been used for pain relief.  These investigators examined the clinical effectiveness of BT type B and compared this with the effectiveness of steroids.  A total of 61 patients diagnosed with SB or SIS were divided into 2 groups and treated with BT type B (BT group) and triamcinolone injection (TA group) under ultrasound (US) guidance, respectively.  Numeric rating scale (NRS), active shoulder abduction angle, and the Korean version of the score on the Disability of Arm, Shoulder, and Hand (DASH) were measured before the treatment, and at 1 and 3 months after the treatment.  Both groups obtained a significant improvement of NRS, DASH, and active shoulder abduction at 1- and 3-month follow-ups.  BT group showed significantly better outcomes in terms of reduction of NRS and DASH at 3 months than TA group.  BT group showed strong trend toward the larger degree of active shoulder abduction than the TA group at 3-month follow-up, as well.  Whereas, no significant difference was found in NRS, DASH, and active shoulder abduction between the 2 groups at 1-month follow-up.  The authors concluded that BT type B can be a useful strategy and has great potential for replacing steroids as a treatment for SB or SIS.

Molini et al (2012) noted that local injection of cortisone derivatives, sometimes combined with local anesthetics, is frequently administered in rheumatology as the treatment of choice in para-articular diseases or as an adjuvant to systemic therapy in the treatment of arthritis.  One of the most frequent local corticosteroid injections administered in daily clinical practice by rheumatologists, orthopedic surgeons, physiatrists, sports medicine doctors and general practitioners is injection into the subacromial subdeltoid bursa in the treatment of bursitis and SIS.  Before local corticosteroid injection is administered, it is important to identify possible contraindications and to examine the documentation provided by the patient.  Absolute contraindications or those related to the procedure should be evaluated by the prescribing physician but also the physician performing the corticosteroid injection should evaluate possible contraindications to make sure that corticosteroid injection is feasible.  These investigators described the US-guided local corticosteroid injection procedure with particular attention to the equipment required, the position of the patient and the examiner as well as the approach.  The main advantage of US guidance during corticosteroid injection is the possibility to identify vascular structures, nerves and tendons situated in the needle path in order to avoid these structures and be sure to inject the drug into the appropriate location.  When all rules were complied with and the corticosteroid injection was performed by an experienced physician, it was virtually painless and was carried out in just a few mins.  This was a technical note; it did not compare US-guided injections with landmark-guided (blind) injections.

Hsieh et al (2013) stated that although US-guided subacromial injection has shown increased accuracy in needle placement, whether US-guided injection produces better clinical outcome is still controversial.  These researchers compared the efficacy of subacromial corticosteroid injection under US guidance with palpation-guided subacromial injection in patients with chronic subacromial bursitis.  Patients with chronic subacromial bursitis were randomized to a US-guided injection group and a palpation-guided injection group.  Participants in each group were injected with a mixture of 0.5-ml dexamethasone suspension and 3-ml lidocaine into the subacromial bursa.  The primary outcome measures were the visual analog scale (VAS) for pain and active and passive ranges of motion (ROM) of the affected shoulder.  Secondary outcome measures were the Shoulder Pain and Disability Index (SPADI), the Shoulder Disability Questionnaire (SDQ), and the 36-item Short-Form Health Survey (SF-36).  The primary outcome measures were evaluated before, immediately, 1 week, and 1 month after the injection; the secondary outcome measures were evaluated before, 1 week, and 1 month after the injection.  Of the 145 subjects screened, 46 in each group completed the study.  Significantly greater improvement in passive shoulder abduction and in physical functioning and vitality scores on the SF-36 were observed in the US-guided group.  The pre- and post-injection within-group comparison revealed significant improvement in the VAS for pain and ROM, as well as in SPADI, SDQ, and SF-36 scores, in both groups.  The authors concluded that the findings of this study demonstrated that subacromial corticosteroid injection, either with the palpation-guided method or under US guidance, was effective in reducing pain, increasing ROM, and improving SDQ, SPADI, and SF-36 scores in patients with chronic SAB.  Furthermore, US-guided injection technique yielded significant improvement in shoulder passive abduction and some items of the SF-36 compared with the blind injection technique.  In a clinic without a US machine, these investigators suggested palpation-guided injection of corticosteroid into the subacromial bursa for patients with chronic SAB; however, if palpation-guided injection failed, or a US machine is available, injection under US guidance is recommended.

The authors stated that this study had several drawbacks.  First, they only performed follow-up assessments 1 month after the treatment; thus, the long-term effects of the treatments were unknown.  Second, these researchers did not include an untreated control group for ethical and practical reasons.  However, because most of the subjects had experienced shoulder pain for longer than 3 months without signs of spontaneous improvement, these investigators believed spontaneous recovery in a short period was unlikely.  Third, these researchers did not use MRI to screen the patients; therefore, some labral lesions may have been missed in the sonography and plain x-ray of the shoulder.  Fourth, even diagnostic block with local anesthetics for confirmation of SAB was not 100 % accurate, the spread of local anesthetics to other tissues (e.g., rotator cuff or ligaments), could not be excluded (but rotator cuff lesion could have been excluded during physical examination or ultrasonography).

Xiao et al (2017) stated that adhesive capsulitis (AC) is a self-limiting condition in a majority of patients and is often treated non-operatively.  However, symptoms may take 2 to 3 years to resolve fully.  A small, but significant, portion of patients require surgical intervention.  In a systematic review, these investigators examined the efficacy of corticosteroid injections for the treatment of AC.  They carried out a review of articles indexed by the U.S. National Library of Medicine (NLM) by querying the PubMed data-base for studies involving patients with AC, frozen shoulder, stiff shoulder, or painful shoulder.  Articles that included corticosteroids, glucocorticoids, steroids, and injections were included.  Corticosteroid injections provide significant symptom relief for 2 to 24 weeks.  Injections can be performed intra-articularly or into the subacromial space.  Evidence suggested that a 20-mg dose of triamcinolone may be as effective as a 40-mg injection; however, it remained unclear whether image-guided injections produced a clinically significant difference in outcomes when compared with landmark-guided (blind) injections.  Corticosteroids may be less beneficial for diabetic patients.  Patients using protease inhibitors (anti-retroviral therapy) should not receive triamcinolone because the drug-drug interaction may result in iatrogenic Cushing syndrome.  The authors concluded that corticosteroid injections for AC demonstrated short-term efficacy; however, it may not provide a long-term benefit.  Moreover, these researchers stated that more high quality, prospective studies are needed to determine whether corticosteroid injections using US guidance significantly improve outcomes.

Furthermore, an UpToDate review on “Bursitis: An overview of clinical manifestations, diagnosis, and management” (Todd, 2021) states that “Limited data suggest that ultrasound-guided injections of the subacromial bursa may be more effective than a "blind" injection; however, this was not validated in a large systematic review.  As ultrasound guidance is not available in real time in many practices, we do not advocate that the use of ultrasound-guided injections is essential”.

Subtalar Joint Injection

Reach et al (2009) stated that US is an emerging imaging modality that affords dynamic, real-time, cost-effective and surgeon controlled visualization of the foot and ankle.  These researchers evaluated the accuracy of US-guided injections for common injection sites in the foot and ankle.  In 10 fresh cadaver feet, US guidance was utilized to inject a methylene blue-saline mixture into the first metatarsophalangeal (MTP) joint, the second MTP joint, the tibio-talar joint, the Achilles peritendinous space, the flexor hallucis longus sheath, the posterior tibial tendon sheath, and the subtalar joint.  Dissection was then undertaken to assess injection accuracy; US guidance allowed the avoidance of intervening neurovascular and tendinous structures; US-guided MTP, ankle, Achilles, PTT and FHL peritendinous injections were 100 % accurate; US-guided subtalar injection was 90 % accurate.  The authors concluded that US appeared to be a highly accurate method of localizing injections into a variety of locations in the foot and ankle.  These investigators stated that US’s ability to display soft-tissue structures may be an advantage over blind injection and fluoroscopic injection techniques.  This was a cadaveric study.

Khosla et al (2009) noted that US has been increasingly utilized in procedures involving intra-articular injections.  These researchers compared the accuracy of intra-articular injections of the foot and ankle using palpation versus dynamic US in a cadaver model.  A total of 14 lightly embalmed cadaver specimens without notable OA were used.  A 0.22-G needle was placed by a foot and ankle orthopedic surgeon into the first and second tarsometatarsal (TMT)  joints, subtalar joint, and ankle joint.  The needle was initially placed using palpation, evaluated with US by an experienced rheumatologist, and re-inserted if necessary.  Needle placement was confirmed with injection of an Omnipaque/methylene blue solution and examined under fluoroscopy, followed by dissection.  Palpation and US were 100 % accurate in subtalar and ankle joint injections.  Using palpation, the needle was correctly placed into the first TMT joint in 3 of 14 cadavers, and in 4 of 14 cadavers for the second TMT joint.  Using US, the needle was correctly placed into the first TMT joint in 10 of 14 cadavers, and into the second TMT joint in 8 of 14 cadavers.  When grouped, US was significantly more accurate for intra-articular needle placement compared to palpation in the mid-foot (p = 0.003).  On 3 specimens, dye extended beyond the second TMT joint.  The authors concluded that intra-articular injections of the subtalar and ankle joints could be successfully performed utilizing palpation alone; US guidance significantly increased injection accuracy into the TMT joints compared to palpation alone and therefore US or fluoroscopy was performed when injecting these TMT joints.  When using selective diagnostic injections into a TMT joint to assess for the symptomatic joint and potential need for arthrodesis, the injected anesthetic may not remain isolated within that joint.  These isolated TMT injections should not be done to answer that question without fluoroscopy confirmation with radiopaque dye demonstrating the injected fluid remained within the one joint of interest.

Superior Cluneal Nerve Injection

Bodner et al (2016) stated that LBP is a disabling and common condition, whose etiology often remains unknown.  A suggested, however rarely considered, cause is neuropathy of the medial branch of the superior cluneal nerves (mSCN) – either at the level of the originating roots or at the point where it crosses the iliac crest, where it is ensheathed by an osseo-ligamentous tunnel.  Diagnosis and treatment have, to-date, been restricted to clinical assessment and blind infiltration with local anesthetics.  In an interventional cadaver study and case-series study, these investigators examined if visualization and assessment of the mSCN with high-resolution US (HRUS) is feasible.  Visualization of the mSCN was assessed in 7 anatomic specimens, and findings were confirmed by HRUS-guided ink marking of the nerve and consecutive dissection.  In addition, a patient chart and image review was performed of patients assessed at the authors’ department with the diagnosis of mSCN neuropathy.  The mSCN could be visualized in 12 of 14 cases in anatomical specimens, as confirmed by dissection; 9 patients were diagnosed with mSCN syndrome of idiopathic or traumatic origin.  Diagnosis was confirmed in all of them, with complete resolution of symptoms after HRUS-guided selective nerve block.  The authors concluded that it is possible to visualize the mSCN in the majority of anatomical specimens.  The patients described may indicate a higher incidence of mSCN syndrome than has been recognized; and mSCN syndrome should be considered in patients with LBP of unknown origin, and HRUS may be able to facilitate nerve detection and US-guided nerve block.  Moreover, these researchers stated that these findings were first results that need to be evaluated in a systematic, prospective and controlled manner.

Suprascapular Nerve Block

In a prospective, randomized study, Kamal et al (2018) compared the effectiveness of suprascapular nerve block (SSNB) under US guidance with anatomical LMG technique in the treatment of chronic shoulder pain.  A total of 50 patients with shoulder pain were enrolled in this trial.  Patients in Group I (n = 25) received SSNB using the anatomical LMG as technique described by Dangoisse, in whom a total of 6 ml of drug (5 ml of 0.25 % bupivacaine and 40 mg methylprednisolone) was injected.  Group II patients (n = 25) were given SSNB using the US guidance with the same amount of drug.  Pain was measured using VAS, ROM and SPADI were recorded.  Observations were recorded before the block, immediately after the block, and 1 and 4 weeks after the block.  There was no statistically significant difference between the VAS score, ROM and SPADI before the procedure (p > 0.05) in both the groups.  Both the groups showed statistically similar improvement of VAS, ROM and SPADI at 4-week (p > 0.05) follow-up.  In Group I, VAS decreased from baseline value of 6.64 ± 1.50-2.04 ± 0.94 at 4 weeks (p < 0.001).  In Group II, the VAS decreased from 6.92 ± 1.00 to 1.84 ± 1.03 at 4 weeks (p < 0.01).  The authors concluded that both techniques produced comparable relief of pain, improvement in shoulder movement, and decreased SPADI 4 weeks after the block.  Moreover, these researchers stated that since only a few studies have evaluated US-guided SSNB for management of chronic shoulder pain, further studies are needed to evaluate and compare it with other LMG techniques of SSNB.

The authors stated that the main drawback of this trial was short-term follow-up (4 weeks) of patients following the block; hence, long-term outcome of both the techniques could not be assessed.  Another drawback was a small sample size (n = 25 in each group), a large sample size could aid in validating these findings.

In a cadaveric study, Laumonerie et al (2019) compared the accuracy of distal SSNB (dSSNB) performed with the use of US-guided regional anesthesia (USRA) versus with a landmark-based approach (LBA).  A secondary objective was to describe the anatomic features of the sensory branches of the dSSN.  USRA and LBA were carried out in 15 shoulders each from 15 cadavers (total of 30 shoulders).  Then, 10-ml of methylene blue-infused ropivacaine 0.75 % was injected into the dSSN.  Simultaneously, 2.5-ml of red latex solution was injected to identify the position of the needle tip.  The division and distribution of the sensory branches originating from the SSN were described.  The tip of the needle was identified at 1.3 cm (range of 0 to 5.2 cm) and 1.5 cm (range of 0 to -4.5 cm) with USRA and the LBA, respectively (p = 0.90).  Staining diffused past the origin of the most proximal sensory branch in 27 cases.  The most proximal sensory branch arose 2.5 cm from the suprascapular notch.  Among the 3 failures that occurred in the USRA group, the sensory branches also failed to be marked.  All 30 dSSNs gave off 3 sensory branches, which innervated the posterior glenohumeral capsule, the subacromial bursa, and the coracoclavicular and acromioclavicular ligaments.  The authors concluded that an LBA was as reliable and accurate as US guidance for anesthetic blockade of the dSSN.  Marking of the suprascapular nerve must be proximal to the suprascapular notch to involve the 3 sensory branches in the anesthetic blockade.  These investigators stated that the findings of this study demonstrated that a LBA to anesthetic blockade of the dSSN was accurate and can be performed by orthopedic surgeons lacking experience in US-guided anesthetic techniques.

In a prospective, randomized study, Saglam and Alisar (2020) compared the clinical and functional outcomes of US-guided versus LMG-SSNB for the treatment of chronic shoulder pain.  A total of 72 patients with chronic shoulder pain were included this trial.  Subjects were randomly allocated to 2 groups: 36 patients received US-guided SSNB and 36 underwent LMG-SSNB.  Initial examinations before injection and for the 1st week and 1st and 3rd months post-injection were recorded.  VAS pain intensity levels, shoulder functions based on the SPADI, and QOL levels based on the Health Assessment Questionnaire (HAQ) were evaluated at each control.  Statistically significant recovery was observed in terms of VAS pain levels, SPADI, and HAQ from the 1st week after injection in both groups, but no significant difference was observed between the groups.  The authors concluded that the findings of this study indicated that US-guided SSNB did not potentially offer a significantly greater clinical improvement over LMG-SSNB in patients with chronic shoulder pain.  These researchers stated that further research is needed to examine if this hypothesis is consistently supported in practice.  The main drawback of this study was the lack of a control group.

Tarsal Tunnel Injection

Redborg et al (2009) noted that the tibial nerve provides the majority of sensation to the foot.  Although multiple techniques have been described, there exists little evidence-based medicine evaluating different techniques for blocking the tibial nerve at the ankle.  These researchers hypothesized that an ultrasound (US)-guided tibial nerve block at the ankle would prove more successful than a conventional approach based on surface landmarks.  A total of 18 healthy volunteers were prospectively randomized into this controlled and blinded study.  Each subject was placed prone, and 1 ankle was randomly assigned to receive either an US-guided tibial nerve block (group US) or a traditional landmark-based tibial nerve block (group LM).  The subject's other ankle then received the alternate approach.  All blocks were performed with 5-ml 3 % chloroprocaine.  These investigators evaluated sensory and motor blocks.  A successful block was defined as complete loss of sensation to both ice and pin-prick at 5 cutaneous sites.  Secondary outcome variables included performance times, number of needle passes, participant satisfaction, and presence of any complications.  At 30 mins, the block was complete in 72 % of participants in the US group as compared with 22 % in the LM group.  At all times, the proportion of complete blocks was higher in the US group.  Ultrasound-guided blocks took longer on average to perform than traditional blocks (159 versus 79 secs; p < 0.001).  There were more needle re-directs in the US group, with 8 subjects requiring 3 or more re-directs versus 0 in the LM group.  Subjects preferred the US block 78 % of the time (95 % confidence interval [CI]: 52 % to 95 %).  The authors concluded that in healthy subjects, US guidance resulted in a more successful tibial nerve block at the ankle than did a traditional approach using surface landmarks.  This was a small study (n = 18) carried out on healthy volunteers.

Chon et al (2014) stated that tarsal tunnel syndrome (TTS) is a compression neuropathy that results from entrapment of the posterior tibial nerve or its branches.  TTS may be treated either by conservative measures, including physical therapy, medications, and steroid injections, or by surgical decompression.  Despite a variety of treatments, a few cases of TTS will relapse, and many cases of recurrent TTS will require re-operation.  Pulsed radiofrequency (PRF) is known to have a number of advantages for pain management, particularly as this technique does not cause neural compromise such as motor weakness.  These investigators reported a new application of US-guided PRF in 2 cases of intractable TTS.  Both patients had a long duration of severe foot pain and had been treated with various therapeutic modalities without lasting relief.  These researchers applied US-guided PRF to the affected posterior tibial nerve in each patient, and both had significantly reduced pain intensity scores and analgesic requirements without any complications.  The authors concluded that US-guided PRF for intractable TTS relieved severe foot pain.  It may supersede surgery as a reliable treatment for intractable TTS.  This was a small (n = 2) case-series study on the use of US-guided PRF for the treatment of TTS.

Burke and Adler (2017) noted that US-guided tibial nerve block allows for rapid anesthetization of the heel and plantar regions of the foot.  These investigators described a variant technique for tibial nerve regional anesthesia utilizing perineural injection of the medial plantar nerve proximal to the sustentaculum tali where the nerve is superficial and readily accessed, with resultant retrograde flow of local anesthetic proximally.  Perineural injection of the medial plantar nerve at the infra-malleolar level provides a simple, safe, and effective alternative method to achieve tibial nerve block for regional anesthesia in a variety of procedures.

Shah et al (2020) stated that the use of US for peripheral nerve blocks has proven extremely useful for improving the accuracy and efficacy of many regional anesthetic techniques.  There remain a few nerve blocks that have lagged behind in employing the assistance of US consistently, one of which is the ankle block.  This block is commonly utilized for either surgical anesthesia or post-operative analgesia for a variety of foot and ankle procedures.  These researchers compared the accuracy of traditional anatomical landmark-guided technique with an US-guided approach for ankle block by assessing the spread of injectate along the posterior tibial nerve (PTN) in cadaver models.  A total of 10 below-knee cadaver specimens were used for this study; 5 were randomly chosen to undergo anatomical landmark-guided PTN blocks, and 5 were selected for US-guided PTN blocks.  The anatomical landmark technique was performed by identifying the medial malleolus and Achilles tendon and inserting the needle (4 cm long, 21-G Braun Stimuplex) at the mid-point of the 2 structures, aiming toward the medial malleolus and advancing until bone was contacted.  The US technique was performed with a linear probe identifying the medial malleolus and the PTN, with the needle subsequently advanced in-plane with a posterior to anterior trajectory until the tip was adjacent to the nerve.  Each specimen was injected with 2-ml of acrylic dye.  All the specimens were dissected following injection to determine which nerves had been successfully coated with dye.  The PTN was successfully coated with dye in all 5 (100 %) US-guided blocks.  In the anatomical landmark group, 2 (40 %) PTN were successfully coated with dye.  Of the 3 unsuccessful attempts, 2 specimens were noted to have dye injected posterior to the PTN; dye was injected into the flexor digitorum longus tendon in 1.  The authors concluded that the base of evidence has dramatically increased in recent years in support of the use of US in regional anesthesia.  This study substantiated the superiority of US guidance for ankle block by demonstrating a 100 % success rate of delivering a simulated nerve block to the correct anatomic location. 

Yurgil et al (2020) noted that family physicians use anesthesia to provide diagnostic and procedural analgesia for conditions such as neuropathies, fracture reduction, foreign body removals, and complex wound management.  Local infiltration of anesthetics is commonly used in this setting because of the ease of use, safety, and effectiveness of the procedure.  Nerve blocks are a specific regional anesthesia technique that blocks nerve function distal to the injection site.  An understanding of the sensory distribution of the peripheral nervous system is essential in determining the safest and most effective nerve block for the procedure.  There are various nerve block techniques, including landmark-guided and US-guided.  Ultrasound guidance increases the effectiveness of the nerve block while decreasing complications when compared with other techniques.  Depending on the required area of anesthesia for the procedure, various points throughout the lower extremity can be used to block the lateral femoral cutaneous, common peroneal, saphenous, tibial, deep peroneal, superficial peroneal, and sural nerves. 

Tendon Injection

Juel et al (2013) established a method for injecting corticosteroid into the rotator interval under US guidance and measured the effect on function, pain and ROM after 4 and 12 weeks.  This study involved a multi-center cohort trial and was carried out at out-patient clinics of the physical medicine and rehabilitation departments in Norway.  A total of 39 patients with adhesive capsulitis lasting between 3 and 12 months were included in this trial; US-guided corticosteroid and lidocaine injection into the rotator interval medial to the biceps tendon using 20-mg triamcinolone hexacetat and 3-ml 20 mg/ml xylocaine.  Change in the shoulder pain and disability index score (SPADI) after 12 weeks was recorded.  The change in SPADI was 42 points (95 % CI: 33 to 51).  Changes in the secondary outcomes showed highly statistically significant increase in active and passive ROM.  One US-guided corticosteroid injection into the rotator interval appeared to give significant improvement in SPADI and active ROM after 12 weeks.  The authors concluded that this study was regarded as regular clinical procedure as injections with triamcinolone already is standard treatment.  This was a small study (n = 39) with short-term follow-up (12 weeks).

Wheeler et al (2016) compared outcomes after 2 different high-volume image-guided injection (HVIGI) procedures performed under direct US guidance in patients with chronic non-insertional Achilles tendinopathy.  In group A, HVIGI involved high-volume (10-ml of 1 % lidocaine combined with 40-ml of saline) and no dry needling.  In group B, HVIGI involved a smaller volume (10-ml of 1 % lidocaine combined with 20-ml of saline) and dry needling of the Achilles tendon.  A total of 34 patients were identified from the clinical records, with mean age of 50.6 (range of 26 to 83) years and mean follow-up duration of 277 (range of 49 to 596) days.  The change between the pre-injection and post-injection Victorian Institute of Sports Assessment-Achilles scores of 33.4 ± 22.5 points in group A and 6.94 ± 22.2 points in group B, was statistically significant (p = 0.002).  In group A, 3 patients (16.7 %) required surgical treatment compared with 6 patients (37.5 %) in group B requiring surgical treatment (p = 0.180).  The authors concluded the findings of this study indicated that a higher volume without dry needling compared with a lower volume with dry needling resulted in greater improvement in non-insertional Achilles tendinopathy.  However, confounding factors meant it was not possible to state that this difference was solely due to different injection techniques.  This was a small study (n = 34); its findings need to be validated by well-designed studies.

Mardani-Kivi et al (2018) compared clinical results of US-guided corticosteroid injection, intra-sheath versus extra-sheath of the finger flexor tendon.  A total of 166 patients with trigger finger were evaluated in a triple-blind, randomized clinical trial study.  All the patients were injected with 1-ml of 40 mg/ml methyl prednisolone acetate, under US-guidance; 50 % the patients were injected extra-sheath, while the other 50 % were injected intra-sheath at the level of first annular pulley.  The 2 groups were comparable in baseline characteristics (age, gender, dominant hand, involved hand and finger, and the symptoms duration).  No significant difference was observed in the 2 groups with regards to Quinnell grading.  In the final visit, 94 % of patients from each group were symptom-free.  The authors concluded that results of corticosteroid injection intra-sheath or extra-sheath of the finger flexor tendon under US guidance in patients with trigger finger were comparably alike; extra-sheath injection at the level of A1 pulley was as effective as an intra-sheath administration.  The main drawback of this trial was the lack of a non-US guidance comparison group.

Laurell et al (2011) noted that the ankle region is frequently involved in juvenile idiopathic arthritis (JIA) but difficult to examine clinically due to its anatomical complexity.  These investigators examined the role of US of the ankle and mid-foot (ankle region) in JIA.  Doppler-US detected synovial hypertrophy, effusion and hyperemia and US was used for guidance of steroid injection and assessment of treatment efficacy.  A total of 40 swollen ankles regions were studied in 30 patients (median age of 6.5 years, range of 1 to 16) with JIA.  All patients were assessed clinically, by US (synovial hypertrophy, effusion) and by color Doppler (synovial hyperemia) before and 4 weeks after US-guided steroid injection.  US detected 121 compartments with active disease (joints, tendon sheaths and 1 ganglion cyst).  Multiple compartments were involved in 80 % of the ankle regions.  The talo-crural joint, posterior subtalar joint, mid-foot joints and tendon sheaths were affected in 78 %, 65 %, 30 % and 55 %, respectively; 50 active tendon sheaths were detected, and multiple tendons were involved in 12 of the ankles.  US guidance allowed accurate placement of the corticosteroid in all 85 injected compartments, with a low rate of subcutaneous atrophy (4.7 %).  Normalization or regression of synovial hypertrophy was obtained in 89 %, and normalization of synovial hyperemia in 89 %.  Clinical resolution of active arthritis was noted in 72 % of the ankles.  The authors concluded that US enabled exact guidance of steroid injections with a low rate of subcutaneous atrophy, and was well-suited for follow-up examinations.  Normalization or regression of synovial hypertrophy and hyperemia was achieved in most cases, suggesting that US assessment prior to steroid injection, and US guidance of injections in this region would potentially improve treatment efficacy.

Young et al (2015) stated that the subtalar joint is commonly affected in children with JIA and is challenging to treat percutaneously.  These researchers described the technique for treating the subtalar joint with US-guided corticosteroid injections in children and young adults with JIA and evaluated the safety of the treatment.  They retrospectively analyzed 122 patients (aged 15 months to 29 years) with JIA who were referred by a pediatric rheumatologist for corticosteroid injection therapy for symptoms related to the hind-foot or ankle.  In these patients the diseased subtalar joint was targeted for therapy, often in conjunction with adjacent affected joints or tendon sheaths of the ankle.  They used a protocol based on age, weight and joint for triamcinolone hexacetonide or triamcinolone acetonide dose prescription.  A total of 241 subtalar joint corticosteroid injections were performed under US guidance, including 68 repeat injections for recurrent symptoms in 26 of the 122 children and young adults.  The average time interval between repeat injections was 24.8 months (range of 2.2 to 130.7, median of 14.2).  Subcutaneous tissue atrophy and skin hypo-pigmentation were the primary complications, which occurred in 3.9 % of the injections.  The authors concluded that with appropriate training and practice, the subtalar joint could be reliably and safely targeted with US-guided corticosteroid injection to treat symptoms related to JIA.

Tendon Scraping/Neovessel Ablation for Achilles Tendinosis

Ruergard and colleagues (2019) stated that treatment with US and color Doppler-guided minimally invasive Achilles tendon scraping and plantaris tendon removal has shown promising short-term results in patients with chronic painful midportion Achilles tendinopathy.  In a follow-up study, a total of 182 consecutive patients (241 tendons) who had undergone Achilles tendon scraping and plantaris tendon removal were contacted on telephone by an independent investigator.  The patients who answered the telephone call were included, and they answered a questionnaire on telephone and then also sent their written answers.  The questionnaire included information regarding patient satisfaction with the result of the treatment, time to return to full Achilles tendon loading activity, and a pain score (VAS).  The follow-up period was 5.8 years (mean) (range of 2 to 13 years) following surgery.  A total of 110 patients (136 Achilles tendons), age of 52 years (mean) (range of 18 to 73) at surgery could be reached and were included.  A total of 81 tendons were operated with the Achilles scraping procedure alone, and for 55 Achilles operations also a plantaris tendon removal was carried out.  For 93 % of the operated tendons, the patients were satisfied with the surgical outcome and the VAS had decreased from 74 pre-operatively to 8 post-operatively; 9 male patients (9 tendons), 5 operated with scraping + plantaris removal, had remaining tendon pain during loading and were not satisfied.  Their VAS score ranged from 22 to 91.  For 21 % of the operated tendons, some occasional mild discomfort not preventing from full tendon loading, was reported.  There were no differences in pain reduction and satisfaction rates between men and women, and between Achilles scraping alone and scraping plus plantaris removal.  The authors concluded that US and color Doppler-guided surgical Achilles tendon scraping and plantaris tendon removal in patients with chronic painful mid-portion Achilles tendinopathy showed remaining good clinical outcomes and high satisfaction rates in this longer-term follow-up.  This study had several drawbacks including not all patients could be reached, and not all who answered the telephone interview later answered the written questionnaire.  Another drawback was the use of only a questionnaire follow-up.  It would have been ideal to also conduct a clinical and US follow-up.

Masci et al (2021) noted that studies have shown that a sub-group of patients with medial Achilles pain exhibit Achilles tendinopathy with plantaris tendon involvement.  This clinical condition is characterized by structural relationships and functional interference between the 2 tendons, resulting in compressive or shearing forces.  Surgical plantaris tendon removal together with an Achilles scraping procedure has shown positive short-term clinical results.  In a case-series study, these researchers examined the long-term outcomes on pain and Achilles tendon structure.  A total of 18 consecutive patients (13 males; 5 females; mean age 39 years; mean symptom duration 28 months), of which 3 were elite athletes, were included.  Clinical examination, b-mode US, and US tissue characterization (UTC) confirmed medial Achilles tendon pain and tenderness, medial Achilles tendinopathy plus a plantaris tendon located close to the medial side of the Achilles tendon.  Patients underwent US-guided local Achilles scraping and plantaris tendon removal followed by a structured rehabilitation program.  Outcomes were VISA-A score for pain and function and UTC for Achilles structure.  A total of 16 of 18 patients completed the 24-month follow-up.  Mean VISA-A scores increased from 58.2 (± 15.9) to 92.0 (± 9.2) (MD = 33.8, 95 % CI: 25.2 to 42.8, p < 0.01).  There was an improvement in Achilles structure with mean organized echo pixels (UTC type I+II, in %) increasing from 79.9 (± 11.5) to 86.4 (± 10.0) (MD = 6.5 %, 95 % CI: 0.80 to 13.80, p = 0.01), exceeding the 3.4 % minimum detectable change.  All 16 patients reported satisfaction with the procedure and 14 returned to pre-injury activity levels.  There were no reported complications.  The authors noted that a drawback of this trial was the low sample size and the absence of a control group (or non-surgical cohort); thus, it was not possible to examine if the Achilles scraping procedure, the plantaris removal, a combination, or other factors (such as natural history) were responsible for the improved pain and function and improved tendon structure identified.  The prolonged duration of symptoms in most of the recruited patients and the previous unsuccessful use of conservative treatments meant that it was unlikely that natural history explained the observed outcomes.  Improvements could theoretically be due to the rehabilitation protocol used following surgery, although immediate full weight-bearing loading and a quick return to sports were used.  These researchers stated that future higher-level randomized studies should be carried out, including a comparative non-operative group, or a sham surgical group, to examine the effectiveness of the surgical procedure in this sub-group of patients with mid-portion Achilles tendinopathy and plantaris involvement.

Tenotomy for the Treatment of Lateral Epicondylitis

Shergill and Choudur (2019) stated that lateral epicondylitis is a painful condition related to the myotendinous origin of the extensor muscles at the lateral epicondyle of the humerus.  Primary treatment typically involves the use of rest, non-steroidal anti-inflammatory drugs (NSAIDs), and physiotherapy.  However, in refractory cases where conventional therapy is ineffective, ultrasound (US)-guided injection therapies have become a growing form of treatment.  These include needle tenotomy, autologous whole blood injection (AWB), platelet-rich plasma (PRP) injection and steroid injection.  The consensus regarding the efficacy of individual approaches of US-guided treatment is unclear in the literature; and was explored further in this review.  When evaluating these injection therapies individually, there are multiple case series describing the efficacy of each intervention in refractory lateral epicondylitis.  A systematic review of needle tenotomy demonstrated an improvement in pain symptoms for patients with this condition, but all studies were poorly designed with no placebo or control group.  For PRP therapy, a systematic review performed in 2013 demonstrated a statistically significant improvement in pain and functionality for refractory lateral epicondylitis; however, these studies were similarly associated with a high risk of bias.  Autologous whole blood injection has been examined via well-designed studies to show statistically significant reductions in pain with this intervention.  But very few studies in total have been completed using AWB for lateral epicondylitis; thus, no clear conclusions could be drawn at this time.  Finally, corticosteroid use overall is unsupported in the evidence both in the short- and long-term, especially given that this condition is not an inflammatory pathology.

Furthermore, an UpToDate review on “Elbow tendinopathy (tennis and golf elbow)” (Jayanthi, 2021) lists “ultrasound-guided percutaneous needle tenotomy” as an investigational treatment of possible benefit.

Tibiofibular Joint Injection

In a cadaveric study, Smith et al (2010) described a technique for sonographically-guided proximal tibiofibular joint (PTFJ) injections and compared its accuracy with that of palpation-guided injections.  A single experienced operator completed 12 sonographically-guided and 12 palpation-guided PTFJ injections in un-embalmed cadavers.  The injection order was randomized, and all injections were completed with diluted colored latex.  Co-investigators blinded to the injection technique dissected each specimen and graded the colored latex location as accurate (in the PTFJ), accurate with overflow (within the PTFJ but also in other regions), or inaccurate (no latex in the joint).  For statistical analysis, all injections placing latex within the PTFJ were considered "accurate”, whereas "inaccurate" injections resulted in no PTFJ latex.  All 12 sonographically-guided PTFJ injections accurately placed latex into the PTFJ (100 % accuracy), whereas only 7 of 12 palpation-guided injections (58 %) placed latex within the PTFJ (p = 0.01).  All 5 inaccurate palpation-guided injections were superficial and inferior to the PTFJ; 4 of 12 accurate sonographically-guided PTFJ injections (33 %) showed some overflow into the adjacent anterior musculature, whereas 5 of the accurate palpation-guided injections (42 %) resulted in overflow into the anterior musculature (n = 1), knee joint (n = 2), or both (n = 2).  The authors concluded that the findings of this cadaveric study suggested that sonographic guidance can be used to inject the PTFJ with a high degree of accuracy and should be considered superior to palpation guidance.  Clinicians should consider using US guidance to inject the PTFJ for diagnostic or therapeutic purposes when clinically indicated.  This was a cadaveric study.

Daniels et al (2018) noted that office-based US has become increasingly available in many settings, and its use to guide joint and soft tissue injections has increased.  Many studies have been carried out to examine the use of US-guided injections over traditional landmark-guided injections, with a rapid growth in the literature over the past few years.  These researchers performed a comprehensive review of the literature to demonstrate increased accuracy of US-guided injections regardless of anatomic location.  In the upper extremity, US-guided injections have been shown to provide superior benefit to landmark-guided injections at the glenohumeral joint, the subacromial space, the biceps tendon sheath, and the joints of the hand and wrist; US-guided injections of the acromioclavicular and the elbow joints have not been shown to be more effective.  In the lower extremity, US-guided injections at the knee, ankle, and foot have superior efficacy to landmark-guided injections.  Conclusive evidence is not available regarding improved efficacy of US-guided injections of the hip, although landmark-guided injection was performed less commonly at the hip joint.  Ultrasound-guided injections are overall more accurate than landmark-guided injections.  The authors concluded that while current studies indicated that US guidance improved efficacy and cost-effectiveness of many injections, these studies were limited; and more research is needed.  This review did not specifically address US-guided injections into the tibiofibular joint, but the study by Smith et al (2010) was cited in the “References”.

Trigger Finger Injection

Callegari et al (2011) noted that stenosing tenosynovitis (trigger finger) is one of the most common causes of pain and disability in the hand, which may often require treatment with anti-inflammatory drugs, corticosteroid injection, or open surgery.  However, there is still room for improvement in the treatment of this condition by corticosteroid injection.  The mechanical, viscoelastic, and anti-nociceptive properties of hyaluronic acid (HA) may potentially support the use of this molecule in association with corticosteroids for the treatment of trigger finger.  In a single-center, open-label, randomized study, these researchers examined the feasibility and safety of ultrasound (US)-guided injection of a corticosteroid and HA compared, for the first time, with open surgery for the treatment of trigger finger.  Consecutive patients aged between 35 and 70 years with US-confirmed diagnosis of trigger finger were included.  Patients were randomly assigned to either US-guided injection of methylprednisolone acetate 40 mg/ml with 0.8 ml lidocaine into the flexor sheath plus injection of 1 ml HA 0.8 % 10 days later (n = 15; group A), or to open surgical release of the first annular pulley (n = 15; group B).  Clinical assessment of the digital articular chain was conducted prior to treatment and after 6 weeks, and 3, 6, and 12 months.  The duration of abstention from work and/or sports activity, and any treatment complications or additional treatment requirements (e.g., physiotherapy, compression, medication) were also recorded.  A total of 14 patients (93.3 %) in group A had complete symptom resolution at 6 months, which persisted for 12 months in 11 patients (73.3% ), while 3 patients experienced recurrences and 1 experienced no symptom improvements.  No patients in group A reported major or minor complications during or after corticosteroid injection, or required a compression bandage.  All 15 patients in group B achieved complete resolution of articular impairment by 3 weeks after surgery, but 10 patients were assigned to physiotherapy and local and/or oral analgesics for complete resolution of symptoms, which was approximately 30 to 40 days post-surgery.  The mean duration of abstention from work and/or sport was 2 to 3 days in group A and 26 days in group B.  The authors concluded that although the limited sample size did not allow any statistical comparison between treatment groups, and therefore all the findings should be regarded as preliminary, the results of this explorative study suggested that US-guided injection of a corticosteroid and HA could be a safe and feasible approach for the treatment of trigger finger.  It was also associated with a shorter recovery time than open surgery, which led to a reduced abstention from sports and, in particular, work activities, and thus may have some pharmaco-economic implications, which may be further examined.  In light of the promising findings obtained in this investigation, further studies comparing US-guided injection of corticosteroid plus HA with corticosteroid alone are recommended in order to clarify the actual benefits attributable to HA.

The authors stated that this study had several drawbacks.  A lack of a corticosteroid-only treatment arm meant that any benefits of adding HA to the regimen of injection compared with corticosteroid alone cannot be shown.  In light of the promising results obtained in this investigation, further study comparing ultrasound-guided injection of corticosteroid plus HA with corticosteroid alone, or exploring other treatment strategies (e.g., no US-guided injection, corticosteroid only versus surgery) is recommended.  Furthermore, due to small patient numbers in this study (a total of 30 subjects) , it was not possible to analyze for any trends in the duration of symptoms or number of injections and success rates.  These researchers stated that further studies with a larger sample size are needed to provide new insights on the safety and effectiveness of US-guided injection of corticosteroid plus HA.  It also must be acknowledged that, due to the explorative nature of this study and the low number of patients enrolled, neither a calculation of power nor a statistical comparison between groups were performed.

In a prospective, double-blinded, randomized controlled trial (RCT), Liu et al (2015) examined the effects of US-guided injections of HA versus steroid for trigger fingers in adults.  Subjects with a diagnosis of trigger finger (n = 36; 39 affected digits) received treatment and were evaluated.  Subjects were randomly assigned to HA and steroid injection groups.  Both study medications were injected separately via US guidance with 1 injection.  The classification of trigger grading, pain, functional disability, and patient satisfaction were evaluated before the injection and 3 weeks and 3 months after the injection.  At 3 months, 12 patients (66.7 %) in the HA group and 17 patients (89.5 %) in the steroid group exhibited no triggering of the affected fingers (p = 0.124).  The treatment results at 3 weeks and 3 months showed similar changes in the Quinnell scale (p = 0.057 and 0.931, respectively).  A statistically significant interaction effect between group and time was found for visual analog scale (VAS) and Michigan Hand Outcome Questionnaire (MHQ) evaluation (p < 0.05).  The steroid group had a lower VAS at 3 months after injection (steroid 0.5 ± 1.1 versus HA 2.7 ± 2.4; p < 0.001).  The HA group demonstrated continuing significant improvement in MHQ at 3 months (change from 3 week: steroid -2.6 ± 14.1 versus HA 19.1 ± 37.0; p = 0.023; d = 0.78).  The authors concluded that US-guided injection of HA demonstrated promising results for the treatment of trigger fingers.  These researchers stated that the optimal frequency, dosage, and molecular weight of HA injections for trigger fingers deserve further investigation for future clinical applications.

Cecen et al (2015) noted that trigger digit is one of the most common causes of pain and disability in the hand.  The mainstay of conservative treatment of this disease has been local steroid injection into the tendon sheath.  In a prospective, randomized, case-control study, these investigators examined the clinical benefit of an US-guided corticosteroid injection compared to a blinded application.  A total of 74 patients, who suffered from persistent or increasing symptoms of a single trigger digit, were enrolled in this trial.  All patients were treated with an injection of 40 mg/1 ml methylprednisolone acetate into the flexor tendon sheath at the level of the A1 pulley; 50 % of the patients had their injections under US control (USG) and 50 % without (blinded injection group, BIG).  Associated metabolic diseases were recorded.  At the 6-week and 6-month follow-up examinations, the complication rate and the need for a second injection were assessed.  The outcome was rated using the Quinnell grading.  The pain level was assessed using the VAS.  A total of 4 patients were excluded due to lack of follow-up.  Both study groups were comparable in respect of age, hand dominance and associated diseases.  There were significantly more female patients in the USG group (32 versus 23 %).  After the corticosteroid injections, all patients improved significantly in terms of pain level and the Quinnell grading at 6 weeks and 6 months after the intervention in comparison to the pre-injection status.  There were no significant differences between the groups; 9 patients (13 %) needed a second injection (6 of BIG, 3 of USG), all of whom had diabetes mellitus.  No local complications were observed following the injections.  The authors concluded that the use of US-guided injection of corticosteroid may be associated with extra time and effort, with no superior clinical benefits compared to the blinded technique.  Level of Evidence =  1 (prospective randomized study).

Wang et al (2017) stated that US is a versatile imaging modality that can be used by upper extremity (UE) surgeons for diagnostic purposes and guided injections.  The perceptions of US for diagnosis and treatment among UE surgeons and its barriers for adoption have not been formally surveyed.  These researchers determined the current usage of musculoskeletal US for diagnostic purposes and guided injections by UE surgeons and their reasons for using it or not using it in practice.  A 22-question survey was distributed to the American Society for Surgery of the Hand (ASSH).  The survey questions consisted of respondent characteristic questions and questions pertaining to the use of US.  Chi-square analysis was performed to assess for a difference in US usage across respondent characteristics.  A total of 304 (43 %) answered that they have an US machine in their office; 51 % (362) of the respondents used US for diagnostic purposes; 55 (8 %) of the survey respondents used US to diagnose carpal tunnel syndrome; 168 (23.5 %) respondents reported that they used US for guided injections.  There was a statistically significant difference between access to an US machine in the office by practice setting and use of US for diagnostic purposes by practice setting.  The authors concluded that the use of US by UE surgeons is split for diagnostic purposes, with fewer surgeons using US to diagnose carpal tunnel syndrome and guided injections.  These investigators stated that US machine availability and the use of US for diagnosis appear to be influenced by practice setting.

Hansen et al (2017) noted that trigger finger is a common condition with a lifetime prevalence of 2 %.  Corticosteroid injection is often considered as a first-line intervention with reported cure rates between 60 % and 90 % in observational cohorts.  However, open surgery remains the most effective treatment with reported cure rates near 100 %.  Head-to-head trials on these treatments are limited.  In a single-center RCT, these investigators examined the efficacy of open surgery compared with US-guided corticosteroid injections with a 1-year follow-up.  A total of 165 patients received either open surgery (n = 81) or US-guided corticosteroid injection (n = 84).  Follow-up was conducted at 3 and 12 months.  If the finger had normal movement or normal movement with discomfort at latest follow-up, the outcome was considered a success.  Secondary outcomes were post-procedural pain and complications.  The groups were similar at baseline except for lower alcohol consumption in the open surgery group.  At 3 months, 86 % and 99 % were successfully treated after corticosteroid injection and open surgery, respectively.  At 12 months, 49 % and 99 % were considered successfully treated after corticosteroid injection and open surgery, respectively.  The pain score at latest follow-up was significantly higher in the corticosteroid injection group.  Complications after open surgery were more severe and included 3 superficial infections and 1 iatrogenic nerve lesion.  After corticosteroid injection 11 patients experienced a steroid flare and 2 had fat necrosis at the site of injection.  The authors concluded that open surgery was superior to US-guided corticosteroid injections; however, complications following open surgery were more severe.

Thread Trigger Finger Release With or Without Hydrodissection

Guo et al (2018) noted that after the thread transecting technique was successfully applied for the thread carpal tunnel release, these investigators researched using the same technique in the thread trigger finger release (TTFR).  This study was designed to test the operational feasibility of the TTFR on cadavers and verify the limits of division on the first annular (A1) pulley to ensure a complete trigger finger release with minimal iatrogenic injuries.  The procedure of TTFR was performed on 14 fingers and 4 thumbs of 4 un-embalmed cadaveric hands.  After the procedures, all fingers and thumbs were dissected and visually assessed.  All of the digits and thumbs demonstrated a complete A1 pulley release.  There was no injury to the neurovascular bundle (radial digital nerve in case of thumb), flexor tendon, or A2 pulley for each case.  The authors concluded that this cadaveric study showed that the technique of TTFR was safe and effective, and future clinical study is needed to verify the findings of this study.

Furthermore, an UpToDate review on "Trigger finger (stenosing flexor tenosynovitis)" (Blazar and Aggarwal, 2019) does not mention thread trigger finger release as a therapeutic option.

Paulius and Maguina (2009) stated that trigger fingers can be treated by open or percutaneous division of the A1 pulley.  The open approach allows for visualization of the pulley, the tendon, and the adjacent neurovascular bundles.  The percutaneous trigger finger release (PTFR) lacks an incision and is thought to lead to a quicker recovery, but the safety and efficacy of this blind procedure are often questioned.  Ultrasound (US) imaging has recently been introduced as an adjunct for guiding the needle during PTFR.  This study was designed to examine the safety and efficacy of needle trigger finger release with added US imaging.  A total of 18 fresh cadaver A1 pulleys were divided percutaneously and then evaluated by converting to an open technique and examining the pulleys, the tendons, and the neurovascular bundles.  This study's US images demonstrated repeated puncture of the tendon sheath and of the neurovascular bundle during PTFR.  The subsequent dissection revealed 3 out of 18 tendons with visible lacerations and 15 out of 18 A1 pulleys with incomplete division.  The authors concluded that US-guided PTFR can be complicated by flexor tendon lacerations, potential injury to neurovascular bundles, and incomplete division of the A1 pulleys.  These researchers stated that while the clinical significance of these findings was unclear, it raised questions regarding the safety and efficacy of PTFR, even when adding US guidance.

Rajeswaran et al (2009) evaluated a new technique for US-guided percutaneous release of the annular pulley in trigger digit using a modified hypodermic needle.  A total of 35 US-guided percutaneous releases were performed on 25 patients diagnosed and referred by hand surgeons in the authors’ institution over 16 months from October 2006.  Inclusion criteria were as follows: adulthood, triggering present for at least 4 months, failure to respond to conservative management or steroid injections, no previous history of pulley release in the affected digit.  Under US guidance, the affected pulley was released using a standard 19-G hypodermic needle bent at 2 points as the cutting device.  Follow-up took place at 12 weeks and 6 months with improvement in triggering and clinically graded pain.  At follow-up, no complications had occurred and all patients demonstrated improvement in their triggering, with complete resolution in 32 digits (91 %), good improvement in 2 digits (6 %) and some improvement in 1 digit (3 %).  The authors concluded that this new technique used a widely available and safe cutting device and was safe and could be used to provide definitive management for trigger finger, allowing the procedure to be performed in a variety of clinical settings.

Rojo-Manaute et al (2010) defined in volunteers a safe area for performing a percutaneous intra-sheath first annular (A1) pulley release under US guidance in cadavers for the treatment of trigger fingers.  First, in 100 fingers of 10 volunteers, these researchers used Doppler US to determine the limits of the sectors enclosing structures at risk (arteries and tendons).  From the synovial sheath's most volar point, these investigators determined the relative position of the arterial walls and the distance to the flexor tendons.  A scatter-plot overlay of the arterial positions was digitally analyzed for determining the limits of the safe area.  Second, these researchers released the A1 pulley in 46 fingers from 5 cadavers, directing the edge of the cutting device toward the safe area from an intra-sheath instrument position.  The precision, safety, and efficacy of the release were evaluated by surgical exposure of the A1 and A2 pulleys and the neurovascular bundles.  In the volunteers, these investigators observed a volar safe area from +6.1° to +180°.  Surgical precision was good in the cadavers, with no injuries to adjacent structures, a complete release in 44 fingers (95.7 %), and an incomplete release of less than 1.6 mm in 2 fingers.  The authors concluded that the findings of this study determined a safe volar area for aiming surgical instruments from an intra-sheath position for percutaneous US-guided A1 pulley release.  The technique can be performed safely in all fingers, but these researchers suggested being cautious in the thumb and converting the surgery to an open procedure if US visualization is not optimal.

Hoang et al (2016) noted that trigger finger is the most common entrapment tendinopathy, with a lifetime risk of 2 % to 3 %.  Open surgical release of the flexor tendon sheath is a commonly performed procedure associated with a high rate of success.  Despite reported success rates of over 94 %, PFTR remains a controversial procedure because of the risk of iatrogenic digital neurovascular injury.  These researchers examined the safety and efficacy of traditional percutaneous and US-guided A1 pulley releases performed on a perfused cadaveric model.  First annular pulley releases were performed percutaneously using an 18-G needle in 155 digits (124 fingers and 31 thumbs) of un-embalmed cadavers with restored perfusion.  A total of 45 digits were completed with US guidance and 110 digits were completed without it.  Each digit was dissected and assessed regarding the amount of release as well as neurovascular, flexor tendon, and A2 pulley injury.  Overall, 114 A1 pulleys were completely released (74 %).  There were 38 partial releases (24 %) and 3 complete misses (2 %).  No significant flexor tendon injury was observed.  Longitudinal scoring of the flexor tendon was found in 35 fingers (23 %).  There were no lacerations to digital nerves and 1 ulnar digital artery was partially lacerated (1 %) in a middle finger with a partial flexion contracture that prevented appropriate hyper-extension.  The US-assisted and blind PTFR techniques had similar complete pulley release and injury rates.  The authors concluded that both traditional and US-assisted percutaneous release of the A1 pulley can be performed for all fingers.  Perfusion of cadaver digits enhanced surgical simulation and evaluation of PTFR beyond those of previous cadaveric studies.  The addition of vascular flow to the digits during percutaneous release allowed for Doppler flow assessment of the neurovascular bundle and evaluation of vascular injury.


Appendix

Note on Documentation Requirements: CPT guidelines state that "Ultrasound guidance procedures also require permanently recorded images of the site to be localized, as well as a documented description of the localization process, either separately or within the report of the procedure for which the guidance is utilized. Use of ultrasound, without thorough evaluation of organ(s), or anatomic region, image documentation, and final, written report, is not separately reportable".


References

The above policy is based on the following references:

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