Phonophoresis

Number: 0210

Policy

Aetna considers the use of phonophoresis experimental and investigational for all indications, including any of the following (not an all-inclusive list):

  • Adhesive capsulitis
  • Carpal tunnel syndrome
  • Chronic non-bacterial prostatitis
  • Chronic rhinosinusitis
  • Epicondylalgia
  • Iliotibial band syndrome
  • Knee osteoarthritis / knee pain
  • Low back pain
  • Medial tibial stress syndrome
  • Myositis ossificans
  • Patellofemoral pain syndrome
  • Rotator cuff tendinopathy
  • Shoulder impingement syndrome
  • Sinusitis
  • Temporomandibular joint disorders
  • Trapezio-metacarpal joint arthritis
  • Traumatic muscle injury
  • Tuberculous lymphadenitis
  • Upper trapezius latent myofascial trigger point.

Phonophoresis has been used to enhance the absorption of analgesics and anti-inflammatory agents.  Controlled clinical trials, however, have failed to demonstrate that phonophoresis increases the rate or extent of absorption of these agents.

Background

Phonophoresis, also known as sonophoresis, has been claimed to enhance the percutaneous absorption of certain pharmacological agents such as anti-inflammatory steroids and local anesthetics from intact skin into the underlying subcutaneous structures by ultrasound, therefore improving their effectiveness.  This procedure is commonly used in physical therapy practices.  The procedure generally utilizes an ultrasound apparatus that generates frequencies of 0.7 to 1.1 MHz.  The ultrasound intensities employed usually range from 0.0 to 3.0 Watts per cm2.  Both continuous-mode as well as pulse-mode applications were utilized, and most treatments lasted from 5 to 8 mins, with the exception of treatments of larger areas (greater than 36 cm2) requiring more than 8 mins.  The exact mechanism enabling drugs to be propelled into the subcutaneous structures is still unclear.

Phonophoresis has been suggested by early studies to enhance the absorption of analgesics and anti-inflammatory agents.  More recent, better-controlled studies have consistently failed to demonstrate that phonophoresis increases the rate of absorption or the extent of absorption over placebo.  Several reviews stated that more research is needed to ascertain optimal techniques and conditions for safe and efficacious utilization of physical modalities including phonophoresis; and there is a need for additional research to establish clinical effectiveness and determine optimal treatment parameters for the physical agents (e.g., phonophoresis) used most frequently to alleviate pain in hand therapy.

In a randomized study (n = 60) comparing the effectiveness of ibuprofen phonophoresis with conventional ultrasound therapy in patients with knee osteoarthritis, Kozanoglu et al (2003) found that ibuprofen phonophoresis was not superior to conventional ultrasound.

Ellis et al (2007) stated that Iliotibial band friction syndrome (ITBFS) is a common injury of the lateral aspect of the knee particularly in runners, cyclists and endurance sports.  A number of investigators suggested that ITBFS responds well to conservative treatment, however, much of this notion appears anecdotal and is not supported by available evidence.  These researchers performed a systematic review of the literature on the conservative treatment of ITBFS.  With respect to the management of ITBFS, 4 randomized controlled trials were identified.  The interventions examined included the use of non-steroidal anti-inflammatory drugs, deep friction massage, phonophoresis versus immobilization and corticosteroid injection.  This review highlighted both the paucity in quality and quantity of research regarding the conservative treatment of ITBFS.  There seems limited evidence to suggest that the conservative treatments that have been studied offer any significant benefit in the management of ITBFS.  The authors noted that future research will need to re-examine those conservative therapies, which have already been examined, along with others, and will need to be of sufficient quality to enable accurate clinical judgements to be made regarding their use.

In a review on factors that influence the quality and effectiveness of ultrasound and phonophoresis treatment, Goraj-Szczypiorowska and colleagues (2007) noted that although phonophoresis is commonly used among physical therapists, doubts persist as to the relevance and effectiveness of this method.  Despite its popularity, the issue of conditions underlying the effectiveness of phonophoresis treatment has still not been adequately addressed.  Particular areas of interest include:
  1. treatment parameters to be followed in physical therapy,
  2. appropriate dosage forms of drugs to ensure propagation of ultrasound waves,
  3. principles of homoeostasis and other physiological processes that play a decisive role in achieving the biological and therapeutic effects of ultrasound therapy, and
  4. indications and contraindications to this kind of treatment.  The dearth of objective research methods and reliable scientific verification does not allow unambiguous determination of the effectiveness of phonophoresis.

Jewell et al (2009) examined if physical therapy interventions predicted meaningful short-term improvement in 4 measures of physical health, pain, and function for patients diagnosed with adhesive capsulitis.  Data were examined from 2,370 patients (mean age of 55.3 years, SD = 12.4; 65 % females, 35 % males) classified into ICD-9 code 726.0 who had completed an episode of outpatient physical therapy.  Principal components factor analysis was used to define intervention categories from specific treatments applied during the episode of care.  A nested logistic regression model was used to identify intervention categories that predicted a 50 % or greater change in Physical Component Summary-12 (PCS-12), physical function (PF), bodily pain (BP), and hybrid function (HF) scores.  None of the patients achieved a 50 % or greater improvement in PCS-12 scores.  Improvement in BP scores was more likely in patients who received joint mobility interventions (odds ratio [OR] = 1.35, 95 % confidence interval [CI]: 1.10 to 1.65).  Improvement in HF scores was more likely in patients who received exercise interventions (OR = 1.50, 95 % CI: 1.03 to 2.17).  Use of iontophoresis, phonophoresis, ultrasound, or massage reduced the likelihood of improvement in these 3 outcome measures by 19 % to 3 2%.  The authors concluded that these results are consistent with findings from randomized clinical trials that demonstrated the effectiveness of joint mobilization and exercise for patients with adhesive capsulitis.  However, ultrasound, massage, iontophoresis, and phonophoresis reduced the likelihood of a favorable outcome, which suggests that use of these modalities should be discouraged.

An UpToDate review on “Rotator cuff tendinopathy” (Simons and Kruse, 2014) lists electrical stimulation, iontophoresis, laser, phonophoresis, and therapeutic ultrasound as adjunct therapies.  Moreover, it states that “No clear evidence exists to support the use of the modalities listed here and we do not routinely use them in the care of our patients”.

Jain et al (2010) hypothesized that transdermal steroid delivery would yield short-term improvements for trapezio-metacarpal (TM) joint arthritis, although these improvements would not persist at later follow-up (3 or 6 months).  A total of 84 consecutive TM joints in 62 patients presenting to an orthopedic hand surgeon were randomized to receive either steroid delivery by iontophoresis or phonophoresis or placebo delivery via iontophoresis or phonophoresis.  The researchers and patients were blinded as to the treatment assignment.  Patients were evaluated before treatment and at 3 follow-up appointments.  Subjects were assessed via the Michigan Hand Outcomes Questionnaire, Short Form 12, analog pain score, and provocative and strength testing.  The subjects' study group, gender, and arthritic grade were statistically analyzed versus patient-reported and physician-assessed data over the different time points.  Following subject recruitment, 17 joints discontinued the study due to joint discomfort, electing for other treatments.  Approximately 50 % of the 67 subject joints opted for alternative treatment after the first or second follow-up; 34 subject joints completed all follow-up time points.  There was no significant predictive relationship between the independent variables and their ability to predict the 9 dependent measures of pain, strength, and well-being.  There were trends for the pain to decrease over time, although the trends were not uniform between the different pain metrics and groups.  The strength for both iontophoresis groups tended to increase over time, whereas the phonophoresis groups tended to decline.  The authors concluded that although there were some trends in the follow-up data, the overall lack of significant differences in the data suggested that transdermal steroid delivery might not be helpful in providing short- or long-term relief of arthritic symptoms.

Donovan et al (2011) examined the anesthetic effect of 1-MHz phonophoresis using lidocaine on the anterior forearm following 5- and 10-min interventions.  This was a cross-over study in a laboratory involving 22 healthy participants (13 women, 9 men; age, 23.0 +/- 3.2 yrs; height, 169.1 +/- 7.2 cm; weight, 70.9 +/- 13.9 kg).  All subjects received 4 interventions on 4 different days:
  1. 1.5 W/cm, 100 % duty cycle with lidocaine for 5 mins (short);
  2. 1.5 W/cm, 50 % duty cycle with lidocaine for 10 mins (long);
  3. no ultrasound for 10 mins with lidocaine gel (lidocaine sham); and
  4. no ultrasound for 10 mins with ultrasound gel (true sham). 

Skin sensation was measured for analysis.  The main outcome measures were Semmes-Weinstein Monofilament (SWM) scores, with higher scores indicating less sensitivity.  There was a significant time main effect for SWM scores (p < 0.001).  Baseline SWM scores were the lowest (3.00 +/- 0.53; p ≤ 0.006) and post-SWM scores (0 mins) were the highest (3.63 +/- .44; p < 0.001), indicating an anesthetic effect at this time.  The authors concluded that neither the long nor the short treatment decreased skin sensation compared with sham conditions.  All interventions resulted in decreased skin sensation when comparing baseline SWM scores to all post-treatment scores.  Phonophoresis with lidocaine did not result in an enhanced anaesthetic effect on human subjects.

Gurney et al (2011) noted that phonophoresis has been a mainstay in physical therapy.  The most common drug used in phonophoresis is hydrocortisone acetate (HA).  A number of studies have been done examining phonophoresis in the delivery of HA through the skin to underlying tissues; however, a study has never been done examining the absorption of HA using phonophoresis on human connective tissue.  In a randomized controlled study, these researchers examined if phonophoresis will facilitate the transmission of HA in human connective tissue.  A total of 21 patients undergoing anterior cruciate ligament reconstruction surgery were randomly assigned to either a sham or true phonophoresis treatment group.  The latter group received 6 minutes of 10 % HA ultrasound at a point consistent with the gastrocnemius slip of the semitendinosis tendon (treatment site).  The sham group received 6 minutes of 10 % HA ultrasound to the same area, but the ultrasound was not turned on.  The slip and a sample of the distal attachment of the tendon (control) were removed.  Samples were analyzed for HA levels.  Although the mean and median levels of HA found at the treatment site were greater than those of the control site (means, 34.1 versus 22.9 parts per billion; medians, 7 versus 0 parts per billion), the levels of HA found at the treatment site were not significantly greater than those at the control site (p = 0.15).  There were no statistically significant differences between the true and sham phonophoresis groups in HA levels (p = 0.80) nor in age, sex, or skin thickness.  The authors concluded that phonophoresis does not appear to facilitate the absorption of HA in connective tissue when compared with simple absorption (sham).  Thus, the, use of phonophoresis should be re-considered in inflammatory conditions.

Lake and Wofford (2011) determined the effectiveness of therapeutic modalities for the treatment of patients with patella-femoral pain syndrome (PFPS).  In May and August 2010, Medline was searched using the following databases: PubMed, CINAHL, Web of Science Citation Index, Science Direct, ProQuest Nursing & Allied Health, and Your Journals@OVID.  Selected studies were randomized controlled trials that used a therapeutic modality to treat patients with PFPS.  The review included articles with all outcome measures relevant for the PFPS patient: knee extension and flexion strength (isokinetic and isometric), patella-femoral pain assessment during activities of daily life, functional tests (e.g., squats), Kujala patella-femoral score, and electromyographic (EMG) recording from knee flexors and extensors and quadriceps femoris cross-sectional areas.  Authors conducted independent quality appraisals of studies using the PEDro Scale and a system designed for analysis of studies on interventions for patella-femoral pain.  A total of 12 studies met criteria: 1 on the effects of cold and ultrasound together, ice alone, iontophoresis, and phonophoresis; 3, neuromuscular electrical stimulation; 4, EMG biofeedback; 3, electrical stimulation for control of pain; and 1, laser.  Most studies were of low-to-moderate quality.  Some reported that therapeutic modalities, when combined with other treatments, may be of some benefit for pain management or other symptoms.  There was no consistent evidence of any beneficial effect when a therapeutic modality was used alone.  Studies did not consistently provide added benefit to conventional physical therapy in the treatment of PFPS.  The authors concluded that none of the therapeutic modalities reviewed has sound scientific justification for the treatment of PFPS when used alone.

An UpToDate review on “Patellofemoral pain syndrome” (O’Connor and Mulvaney, 2014) states that “There is no empiric evidence to support the use of ultrasound, iontophoresis, phonophoresis, or electrical stimulation in the treatment of PFPS”.

The American College of Occupational and Environmental Medicine’s occupational medicine practice guidelines on “Elbow disorder” (ACOEM, 2012) phonophoresis is not recommended for acute, subacute, or chronic lateral epicondylalgia.  Furthermore, the ACOEM guidelines offer no recommendation regarding the use of phonophoresis for acute, subacute, or chronic ulnar neuropathies at the elbow.

Bakhtiary et al (2013) compared the effectiveness of iontophoresis and phonophoresis of dexamethasone sodium phosphate (Dex-P) treatment for mild-to-moderate carpal tunnel syndrome (CTS).  A total of 52 hands in 34 consecutive patients with mild-to-moderate CTS confirmed by EMG were allocated randomly into 2 groups.  One group received iontophoresis of 0.4 % Dex-P and the other group received phonophoresis of 0.4 % Dex-P.  Phonophoresis (using ultrasound 1 MHz, 5-cm probe, 1.0 W/cm, pulse 1:4, 5 mins/session) and iontophoresis (using galvanic current, negative electrode, 2 mA/min, total dose 40 mA for 20 mins) was applied over the wrist chin for 10 daily treatment sessions (5 sessions/week).  Measurements were performed before and after treatment and at follow-up 4 weeks later, and included pain assessment by visual analog scale, electroneurographic measurement (motor and sensory latency, motor and sensory action potential amplitude), and pinch and grip strength.  Improvement was significantly more pronounced in the phonophoresis group than in the iontophoresis group for motor latency [mean difference 0.8 m/s; 95 % CI: 0.5 to 1.1], motor action potential amplitude (4.1 mV; 95 % CI: 3.0 to 5.2), finger pinch strength (31.6 N; 95 % CI: 15.9 to 47.3), hand grip strength (27.1 N; 95 % CI: 13.5 to 40.5), and pain relief (2.1 points on a 10-point scale; 95 % CI: 1.3 to 2.9).  Effects were sustained in the follow-up period.  The authors concluded that phonophoresis of Dex-P treatment was more effective than iontophoresis of Dex-P for treatment of CTS.  Moreover, they stated that further investigation is needed to examine the combination therapy effects of these treatments with other conservative treatments in CTS patients.

In a case report, Ansari et al (2013) described the results of a novel treatment, erythromycin phonophoresis, in a woman with chronic rhino-sinusitis (CRS).  A 31-year old woman with a 7-month history of CRS refractory to conventional medical management was treated with erythromycin phonophoresis to both maxillary sinuses.  Individual sinus symptom severity was assessed and sinus CT scans were obtained both pre-treatment and post-treatment.  After treatment, the total sinusitis symptom score improved from 12 to 0 and the CT scan showed almost complete disease resolution.  At 5-month follow-up, the patient reported sustained improvement.  The authors concluded that erythromycin phonophoresis has potential as an effective treatment for CRS.

Packer et al (2013) stated that the dental anesthesia sonophoresis device (DASD) is a novel device that is intended to reduce the discomfort associated with intra-oral mucosa needle puncture.  The DASD produces ultrasonic energy that provides a sonophoretic effect on the oral mucosa, generating micro-channels through the lipids between the keratinized cells that make up the stratum corneum.  Once the topical anesthetic has permeated the stratum corneum, it quickly diffuses through the soft tissue, desensitizing the nerve endings and reducing the perception of pain caused by needle penetration.  In a pilot study, these researchers evaluated whether topical anesthesia applied using the DASD will reduce the discomfort of the needle puncture when compared to the control device.  A split-mouth model, using 50 healthy subjects with puncture site at the maxillary canine vestibule, was used for this study.  Subjects received a needle puncture on both sides of the mouth.  Prior to the needle puncture, there was randomized application of 5 % lidocaine with the DASD and a control device.  Subjects rated their discomfort after needle punctures utilizing the visual analog scale pain scoring system.  There was no statistically significant difference in the pain perception using the DASD versus the control device.

Winters et al (2013) stated that medial tibial stress syndrome (MTSS) is a common exercise-induced leg injury among athletes and military personnel.  Several treatment options have been described in the literature, but it remains unclear which treatment is most effective.  The objective of this systematic review was to evaluate the effectiveness of any intervention in the treatment of MTSS.  Published or non-published studies, reporting randomized controlled trials (RCTs) or non-RCTs of any treatment in subjects with MTSS were eligible for inclusion.  Treatments were assessed for effects on pain, time to recovery or global perceived effect.  Computerized bibliographic databases (MEDLINE, CENTRAL, EMBASE, CINAHL, PEDro and SPORTDiscus) and trial registries were searched for relevant reports, from their inception to June 1, 2012.  Grey literature was searched for additional relevant reports.  The Cochrane Risk of Bias Tool was used to appraise study quality of RCTs whereas the Newcastle Ottawa Scale was used to appraise non-RCTs.  The “levels of evidence”, according to the Oxford Centre for Evidence-Based Medicine, addressed the impact of the assessed trials.  Two reviewers independently performed the search for articles, study selection, data extraction and appraised methodological quality.  A total of 11 trials were included in this systematic review.  All RCTs revealed a high-risk of bias (Level 3 of evidence).  Both non-RCTs were found to be of poor quality (Level 4 of evidence).  Randomized clinical trials, studying the effect of a lower leg brace versus no lower leg brace, and iontophoresis versus phonophoresis, were pooled using a fixed-effects model.  No significant differences were found for lower leg braces (standardized mean difference [SMD] -0.06; 95 % CI: -0.44 to 0.32, p = 0.76), or iontophoresis (SMD 0.09; 95 % CI: -0.50 to 0.68, p = 0.76).  Iontophoresis, phonophoresis, ice massage, ultrasound therapy, periosteal pecking and extracorporeal shockwave therapy (ESWT) could be effective in treating MTSS when compared with control (Level 3 to 4 of evidence).  Low-energy laser treatment, stretching and strengthening exercises, sports compression stockings, lower leg braces and pulsed electromagnetic fields have not been proven to be effective in treating MTSS (level 3 of evidence).  The authors concluded that none of the studies was sufficiently free from methodological bias to recommend any of the treatments investigated.  Of those examined, ESWT appeared to have the most promise.

An UpToDate review on “Shoulder impingement syndrome” (Simons et al, 2014) lists acupuncture, electrical stimulation, iontophoresis, laser, phonophoresis, and therapeutic ultrasound as adjunct therapies.  Moreover, it states that “No clear evidence exists to support the use of the modalities listed here in the treatment of SIS, and we do not routinely use them in the care of our patients”.

An UpToDate review on “Overview of geriatric rehabilitation: Program components and settings for rehabilitation” (Hoenig and Kortebein, 2014) states that “Iontophoresis/Phonophoresis -- These modalities utilize electric current (iontophoresis) or ultrasound energy (phonophoresis) to force a therapeutic medication (e.g., glucocorticoid) into tissues.  Both are used to treat soft tissue musculoskeletal injuries.  Although evidence is limited, the few randomized controlled trials indicate that these modalities are generally no more effective than placebo”.

Myositis Ossificans

Bagnulo et al (2014) noted that myositis ossificans (MO) is a potential complication of muscle contusion.  In a case-series study, these researchers presented the findings of patients who developed traumatic MO (confirmed on diagnostic ultrasound) who participated in a treatment regimen consisting of phonophoresis of acetic acid with ultrasound.  In all cases, a trial of phonophoresis therapy significantly decreased patient signs, symptoms and the size of the calcification on diagnostic ultrasound in most at a 4-week post-diagnosis mark.  The authors concluded that due to the potential damage to the muscle and its function that surgical excision carries, safe and effective conservative treatments for MO are crucial.  They also stated that “Research on conservative care is necessary for chiropractors and other manual therapists to appropriately manage patients with MO.  Proving to be effective in this case and the paucity of literature on conservative treatment, this area needs to be investigated … Acetic acid phonophoresis deserves more attention in the literature.  For conclusive information about conservative care, studies must investigate long-term effects of conservative care in a randomized trial with a clinically significant number of participants”.  These findings need to be validated by well-designed studies.

An UpToDate review on “Quadriceps muscle and tendon injuries” (Von Fange, 2016) does not mention phonophoresis as a management tool for MO.

Tuberculous Lymphadenitis

Chen et al (2016) stated that electro-phonophoresis (EP) has been used in various clinical fields.  These researchers evaluated the skin permeability of isoniazid (INH) and rifampicin (RIF) in patients with tuberculous lymphadenitis with the aid of EP to validate the clinical applications of this transdermal delivery system for the treatment of superficial extra-pulmonary tuberculosis.  Isoniazid and RIF solutions were delivered transdermally, with or without EP, in the surrounding tissue of the lesion for 30 minutes.  Local pyogenic fluids or necrotic tissue samples from the infection sites in patients were collected at 1 hour after dosing.  Drug concentrations in samples were evaluated by high performance liquid chromatography.  The median INH and RIF intra-lesional concentrations were 0.365 (interquartile range [IQR] 0.185 to 1.775) μg/ml and 1.231 (IQR 0.304 to 1.836) μg/ml in oral group; 2.964 (IQR 0.193 to 7.325) μg/ml and 2.646 (IQR 1.211 to 3.753) μg/ml in INH- and RIF-transdermal plus EP group.  Drug concentrations in the local sites of patients receiving INH or RIF through EP transdermal delivery were statistically higher than those observed in patients only taking INH and RIF orally.  However, this enhancement was not observed in the transdermal delivery of INH or RIF without EP in contrast to the oral administrations of drugs.  The authors concluded that EP can effectively enhance the skin permeability of INH and RIF in patients with tuberculous lymphadenitis.  The increase in drug concentrations in the lesions could help eradication of the germs; shorten the treatment course and increase the cure rate of patients with tuberculous lymphadenitis.  These finding need to be validated by well-designed studies to show that EP would improve health outcomes in patients with tuberculous lymphadenitis.

An UpToDate review on “Tuberculous lymphadenitis” (Spelman, 2016) does not mention phonophoresis as a management tool.

Knee Pain

In a double blinded, randomized clinical trial, Nakhostin-Roohi et al (2016) evaluated the effects of virgin olive oil phonophoresis on female athletes' anterior knee pain (AKP).  A total of 93 female athletes suffering from AKP voluntarily participated in this study.  Patients were randomly assigned into olive oil (n = 31), piroxicam (n = 31) or base gel phonophoresis (n = 31) groups.  At the baseline visit, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was filled by subjects who were then treated with olive oil, piroxicam or pure phonophoresis for 12 sessions.  After 6 and 12 sessions of physiotherapy, subjects filled the questionnaire again.  Main outcomes were significant improvement in pain, stiffness, physical function, and total WOMAC scores.  Although, there was a significant reduction in symptoms of AKP at the end of the therapy in all groups (p < 0.05), but in olive oil group, this improvement was seen after 6 sessions of treatment (p < 0.001).  A significant difference between olive oil group and piroxicam and/or phonophoresis group was observed after 6 sessions of therapy (p < 0.05).  The authors concluded that it could be proposed that phonophoresis with virgin olive oil is as effective as piroxicam gel on lowering WOMAC scores of AKP in female athletes and also has several beneficial properties including faster effect and shorter duration of therapy.  The exact mechanism of beneficial action of virgin olive oil on AKP is unclear and requires further studies.

Chronic Non-Bacterial Prostatitis

Tantawy and colleagues (2018) noted that a significant number of men who are younger than 50 years visit urologists for interminable prostatitis.  These investigators examined the effect of pumpkin seed oil (PSO) phonophoresis on chronic non-bacterial prostatitis (CNBP).  A total of 60 patients with CNBP were randomly assigned to 3 groups: Group A patients were treated with PSO using phonophoresis; Group B patients underwent trans-perineal continuous low-intensity ultrasound (LIUS); and Group C patients underwent placebo LIUS.  All 3 groups received their corresponding treatments daily for up to 3 weeks.  The NIH-Chronic Prostatitis Symptom Index (NIH-CPSI), residual urine determined by urodynamic measurements, and flow rate were used to analyze study outcomes.  The white blood cell (WBC) count in the prostatic secretion was determined.  Comparisons of the intra-group mean values of all measurements in Groups A and B before and after the end of the treatment showed a significant improvement in residual urine, flow rate, WBC count, and NIH-CPSI (p < 0.05), whereas no significant change was found in Group C (p > 0.05).  Between-group comparisons of all variables showed a significant difference was found after intervention (p < 0.05).  Post-intervention comparisons between Groups A and B showed a significant difference in all measurements, except for WBC, in favor of Group A.  Comparing the changes between Groups A and C, a significant difference was found in all measurements (p < 0.05).  Furthermore, all parameters differed significantly when comparing Groups B and C (p < 0.05).  The authors concluded that the findings of this study demonstrated that PSO phonophoresis could produce a significant effect in the management of CNBP and thus could be considered a safe, non-invasive method for the treatment of CNBP.  Moreover, these researchers stated that future investigations should examine the use of other different herbal sources that can be presented to the body by using different modes of LIUS by phonophoresis.  The outcome measures of the present study were limited to the use of some urodynamic parameters, such as urinary flow rate and residual urine, WBCs, and NIH-CPSI, which were insufficient measures to strongly support the use of the treatment protocol; thus, further studies should be conducted along with the measurement of prostate weight, inflammatory markers in prostatic secretions (tumor necrotic factor [TNF] and interleukin-6 [IL-6] or interleukin-1 beta (IL-1B), nuclear factor-kappaB (NF-kB)), and dihydrotestosterone levels.

Chronic Rhinosinusitis

Griffin and colleagues (2018) noted that the use of alternative medicine in chronic rhinosinusitis (CRS) continues to increase in popularity, for the most part without meeting the burden of being based on sound clinical evidence.  New and emerging treatments, both natural and developed, are numerous, and it remains a challenge for otolaryngologists as well as general practitioners to keep up-to-date with these therapies and their efficacy.  In a systematic review, these investigators discussed a number of alternative therapies for CRS, their proposed physiologic mechanisms, and evidence supporting their use.  This analysis was based on their review of the English-language literature on alternative therapies for CRS (they did not include any therapies that are already recommended by accepted professional bodies).  Data collection was performed using the PubMed database (not restricted to Medline due to the nature of the subject matter), the Cochrane databases, and bibliography searches.  These researchers found that while many of the alternative therapies they reviewed might have a firm basis in science, they lack any clinical evidence to support their use specifically for CRS.  Some emerging therapies, such as therapeutic ultrasonography and phonophoresis, showed some promise, based on a growing body of positive evidence.  In addition, the use of baby shampoo, thyme honey, and bromelain additives to saline lavage in CRS are all supported by clinical evidence, as is Sinupret, an oral preparation that contains echinacea.  The authors concluded that higher levels of evidence gleaned from large, well-designed, prospective, RCTs are needed before any of these therapies can be recommended.

Low Back Pain

In a prospective, double-blind, randomized clinical study, Altan and colleagues (2019) examined the effect of phonophoresis with the combination of non-steroidal anti-inflammatory drugs (NSAID's) and myorelaxant versus routine ultrasound (US) treatment with non-therapeutic gel on the patients with acute low back pain (LBP).  A total of 60 patients with acute LBP were randomly assigned into 2 groups.  In Group 1 (n = 30) US was applied using diclofenac plus thiocolchicoside gel for 10 mins and for a total of 10 sessions.  In Group 2 (n = 30) the same US protocol was applied with the same setting and timing with Group 1 using US gel that did not contain any pharmaceutical ingredient.  Evaluation parameters were visual numeric scale (VNS), Oswestry Disability Index (ODI), and Shober test.  Comparison of the results obtained from the 2 groups before treatment and at 2nd (W2) and 6th weeks (W6) post-treatment showed significant improvement in all parameters in both groups (p < 0.05).  Comparison of the groups showed significantly superior improvement in Group 1 for ODI while there was no difference in other parameters at W2.  At W6, there was significantly superior improvement in all parameters (p < 0.05) except for Shober test in Group 1.  The authors concluded that these findings showed that phonophoresis was superior than conventional US therapy at short-term in the treatment of patients with acute LBP.  The relatively small sample sizes (n = 30 in each group) and the short-term follow-up (6 weeks) were the main drawbacks of this trial.  These researchers suggested that further studies with larger patient groups are needed for better understanding of the effects of phonophoresis in acute and chronic LBP.

Upper Trapezius Latent Myofascial Trigger Point

Tabatabaiee and associates (2019) stated that latent myofascial trigger point (LMTP) is a small hypersensitive area in skeletal muscles that becomes painful under compression or stimulation; and LMTPs are relevant for various musculoskeletal disorders.  Although several treatments have been introduced to treat LMTP, the most efficient one is yet to be found.  These researchers compared the effectiveness of pressure release, phonophoresis of betamethasone and dry needling in treating upper trapezius LMTP.  A total of 60 subjects (mean ± SD age of 23.6 ± 2.1 years), with at least 1 LMTP in the upper trapezius muscle, participated in this study.  Subjects were randomly divided into 3 groups (pressure release, phonophoresis with betamethasone and dry needling groups) for 2 weeks.  Pain intensity, pain pressure threshold and active cervical range of motion (ROM) were assessed.  Significant pain decrease, active cervical ROM and pain pressure threshold increase were observed in the 3 groups (p < 0.001).  The dry needling and phonophoresis groups reported more significant improvement compared to the pressure release group (p < 0.001).  There was no difference between the dry needling and phonophoresis groups.  The authors concluded that considering the significant, positive effects of all 3 methods, dry needling and phonophoresis appeared to be more effective than pressure release in treating upper trapezius LMTP.  This was a relatively small study (a total of 60 subjects), and no follow-up data were provided.  These preliminary findings need to be validated by well-designed studies. 

Carpal Tunnel Syndrome

In a double-blind RCT, Boonhong and Thienkul (2020) examined the effects of phonophoresis of piroxicam (PH-P) and phonophoresis of dexamethasone sodium phosphate (PH-Dex) on mild-to-moderate CTS, and compared each of them with the control group of non-drug US therapy.  Patients with clinical signs and symptoms of CTS underwent an electrophysiological study to confirm the diagnosis of CTS and severity grading; 33 patients, 50 hands (52 % of the patients had bilateral CTS, n = 17) with mild-to-moderate CTS were randomly allocated into 3 study groups: PH-P, PH-Dex, or US.  All 3 groups received 10 sessions of 1-MHz frequency, 1.0 w/cm2 intensity US wave with stroking technique, continuous mode, at the palm side of the hand over the carpal tunnel area -- 10 mins/session, 2 to 3 times per week for 4 weeks, for a total of 10 sessions.  During each session, subjects received 15 cm3 of study gel according to the study groups.  The PH-P group received 0.5 % piroxicam gel mixture (equivalence of 20 mg of piroxicam); the PH-Dex group received 0.4 % dexamethasone sodium phosphate gel mixture (equivalence 60 mg of dexamethasone); and the US group received non-drug gel.  Boston Carpal Tunnel Questionnaire for symptom severity (BCTQ SYMPT), Boston Carpal Tunnel Questionnaire for functional status (BCTQ FUNCT) and electrophysiological parameters of the median nerve including distal sensory latency (DSL) and distal motor latency (DML) were evaluated before the 1st treatment and after the last treatment.  After treatment, all treatment groups (PH-P, PH-Dex, and US) showed significant improvements of the BCTQ SYMPT (p < 0.001, -0.74 ± 0.73 [-1.12 to -0.37], -0.91 ± 0.96 [-1.41 to -0.42], and - 0.68 ± 0.71 [-1.05 to -0.30], respectively) and the BCTQ FUNCT (p < 0.001, -0.68 ± 0.89 [-1.14 to -0.22], -0.74 ± 0.84 [-1.17 to -0.30], and - 0.80 ± 0.80 [-1.22 to -0.37], respectively).  For the BCTQ SYMPT, only the PH-Dex showed an improvement score above MCID at 0.8 level [-0.91 ± 0.96].  The improvement of BCTQ FUNCT score of all groups was above Minimal Clinically Important Difference (MCID) at 0.5 level (-0.68 ± 0.89, -0.74 ± 0.84 and - 0.80 ± 0.80, respectively).  The DSL was decreased in all groups but the changes were not statistically significant (p = 0.70, -0.11 ± 0.34 [-0.28 to 0.06], -0.09 ± 0.32 [-0.26 to 0.07], and - 0.14 ± 0.29 [-0.29 to 0.02], respectively).  The DML showed decrease only in PH-DEX and the US group but it was not statistically significant (p = 0.68, 0.05 ± 0.44 [-0.17 to 0.27], -0.09 ± 0.51[-0.34 to 0.17], and - 0.27 ± 0.49 [-0.53 to 0.01], respectively).  All measured outcomes were not statistically different in between-group-comparison of BCTQ SYMPT, BCTQ FUNCT, DSL, and DML (p = 0.58, p = 0.79, p = 0.20 and p = 0.39, respectively).  However, there was a clinically significant difference of the improvement of BCTQ SYMPT in between-group comparison; only the PH-DEX was above the MCID level, while the PH-P and US were not.  The authors concluded that neither non-drug US nor phonophoresis treatments (PH-P and PH-Dex) were effective to improve the DSL and DML in mild-to-moderate CTS.  All 3 groups showed significant improvements in clinical symptoms (BCTQ SYMPT) and functional status (BCTQ FUNCT).  At 1 MHz frequency and 1.0 w/cm2 intensity of US wave, there was no statistically significant difference between phonophoresis and the non-drug US.  Level of Evidence = I.

Knee Osteoarthritis

In a systematic review and meta-analysis, Wu and colleagues (2019) examined the safety and effectiveness of therapeutic US with sham US on pain relief and functional improvement in patients with knee osteoarthritis (OA).  As phonophoresis is a unique therapeutic US, these researchers also compared the effects of phonophoresis with conventional non-drug US.  PubMed, Embase, and the Cochrane Library were systematically searched for RCTs from inception up to June 2019; RCTs comparing therapeutic US with sham US in knee OA patients were included.  Phonophoresis in the experimental and control groups were compared through conventional US, and corresponding trials were also included; 2 reviewers independently identified eligible studies and extracted data.  Risk of bias assessments and therapeutic US safety assessments were also performed.  A total of 15 studies including 3 phonophoresis-related studies with 1,074 patients were included.  Meta-analyses demonstrated that therapeutic US significantly relieved pain (p < 0.00001) and reduced the WOMAC physical function score (p = 0.03).  In addition, therapeutic US increased the active ROM (p < 0.00001) and reduced the Lequesne index (p < 0.00001).  Subgroup analysis of phonophoresis US showed significant differences on the visual analogue scale (VAS; p = 0.009), but no significant differences on WOMAC pain subscales (p = 0.10), and total WOMAC scores were observed (p = 0.30).  There was no evidence to suggest that US was an unsafe treatment.  The authors concluded that therapeutic US is a safe treatment to relieve pain and improve physical function in patients with knee OA.  However, phonophoresis did not produce additional benefits to functional improvement, but may relieve pain compared to conventional non-drug US.

Temporomandibular Joint Disorders

Ramakrishnan and Aswath (2019) examined the efficacy of phonophoresis in patients with temporomandibular disorders (TMDs).  A total of 50 patients diagnosed clinically and radiographically as TMD were randomly assigned into either of the 2 groups: Group A -- plain US, and Group B -- phonophoresis.  Acoustic gel containing no pharmacological agent was applied in the US group, whereas a gel containing aceclofenac was applied in the phonophoresis group.  Each group was treated thricely-weekly for 2 weeks.  The assessment of pain and inflammation both before and after treatment were carried out using the VAS and C-reactive protein (CRP).  Inter-group comparison was performed and analyzed statistically using independent t-test.  Intra-group comparison was carried out using paired t-test.  A significant difference in VAS scores and CRP levels before and following treatment were observed within both US and phonophoresis groups.  No significant difference was observed statistically between US and phonophoresis group.  The authors concluded that the findings of this study suggested that although plain US as well as phonophoresis with aceclofenac gel were effective in the management of TMD, phonophoresis was found be slightly superior as evident in VAS scores and CRP levels though not statistically significant.

The authors stated that this study had several drawbacks.  The findings reflected the short-term effects of phonophoresis or US therapy; long-term effectiveness has not been examined.  They stated that for a more definitive answer on the use of phonophoresis and therapeutic US in TMDs, large RCTs with long-term follow-up is needed.

Traumatic Muscle Injury

Haupenthal and associates (2020) stated that the repair process consists of molecular and cellular events that can be accelerated by specific therapies.  These researchers examined the effects of ibuprofen phonophoresis associated with gold nanoparticles (GNPs) in the animal model of traumatic muscle injury.  A total of 80 male Wistar rats were divided into 8 groups: Sham; muscle injury (MI); MI + therapeutic pulsed US (TPU); MI + Ibuprofen (IBU); MI + GNPs; MI + TPU+ IBU; MI + TPU + GNPs and MI + TPU + IBU + GNPs.  The lesion in the gastrocnemius was performed by a single direct trauma impact on the injured press.  Animals were treated with pulsed US and the gel with GNPs and/or IBU.  Treatment was applied daily for 5 days and the 1st session was 12 hours after the muscle injury.  The gastrocnemius muscle was surgically removed for analyses -- biochemical, histological, and molecular.  In the analyzes only the MI + TPU + IBU + GNPs group showed a reduction in TNF-a and IL-1 levels, with a concomitant increase in the levels of anti-inflammatory cytokines.  In the analysis of oxidative stress, only the MI + TPU + IBU + GNPs group presented a reversal of the condition when compared to the MI group.  In the histological analysis, the MI group presented a large cell infiltrate and a centralized nucleus and only the MI + TPU + IBU + GNPs group showed a structural improvement, also in the pain results the MI + TPU + IBU + GNPs showed a significant difference in comparison to the MI group (p < 0.01).  The authors believed that the effects of phonophoresis with anti-inflammatory drugs associated with gold nanoparticles may potentiate the reduction of the inflammatory response and regulate the cellular redox state.  These preliminary findings need to be further investigated.

Table: CPT Codes / HCPCS Codes / ICD-10 Codes
Code Code Description

Information in the [brackets] below has been added for clarification purposes.   Codes requiring a 7th character are represented by "+":

Phonophoresis:

No specific code

Other CPT codes related to the CPB:

97035 Application of a modality to one or more areas; ultrasound, each 15 minutes

ICD-10 codes not covered for indications listed in the CPB:

A18.2 Tuberculous peripheral lymphadenopathy
G56.00 - G56.03 Carpal tunnel syndrome
J01.00 - J01.91 Acute sinusitis
J32.0 - J32.9 Chronic sinusitis
M17.0 - M17.9 Osteoarthritis of knee
M19.031 - M19.039 Primary osteoarthritis, wrist
M25.521 - M25.529 Pain in elbow
M25.561 - M25.569 Pain in knee [patellofemoral pain syndrome]
M26.601 - M26.69 Temporomandibular joint disorder
M54.5 Low back pain
M61.00 - M61.19 Myositis ossificans
M75.00 - M75.02 Adhesive capsulitis of shoulder
M75.40 - M75.42 Impingement syndrome of shoulder
M75.80 - M75.82 Other shoulder lesions [rotator cuff tendinopathy]
M76.30 - M76.32 Iliotibial band syndrome
M79.18 Myalgia, other site [upper trapezius latent myofascial trigger point]
N41.1 Chronic prostatitis
S09.19xA - S09.19xS Other specified injury of muscle and tendon of head
S16.8xxA - S16.8xxS Other specified injury of muscle, fascia and tendon at neck level
S29.091A - S29.099S Other injury of muscle and tendon of wall of thorax
S39.091A - S39.093S Other injury of muscle, fascia and tendon of abdomen,lower back and pelvis
S46.091A - S46.099S Other injury of muscle(s) and tendon(s) of the rotator cuff of shoulder
S46.191A - S46.199S Other injury of muscle, fascia and tendon of long head of biceps, arm
S46.291A - S46.299S Other injury of muscle, fascia and tendon of other parts of biceps, arm
S46.391A - S46.399S Other injury of muscle, fascia and tendon of triceps, arm
S46.891A - S46.899S Other injury of other muscles, fascia and tendons at shoulder and upper arm level, arm
S46.991A - S46.999S Other injury of unspecified muscle, fascia and tendon at shoulder and upper arm level, arm
S56.091A - S56.099S Other injury of flexor muscle, fascia and tendon of thumb at forearm level
S56.191A - S56.199S Other injury of flexor muscle, fascia and tendon of index, middle, ring, little, and unspecified finger at forearm level
S56.291A - S56.299S Other injury of other flexor muscle, fascia and tendon at forearm level
S56.391A - S56.399S Other injury of extensor or abductor muscles, fascia and tendons of thumb at forearm level
S56.491A - S56.499S Other injury of extensor muscle, fascia and tendon of finger at forearm level
S56.591A - S56.599S Other injury of other extensor muscle, fascia and tendon at forearm level
S56.891A - S56.899S Other injury of other muscles, fascia and tendons at forearm level
S56.991A - S56.999S Other injury of unspecified muscles, fascia and tendons at forearm level
S66.091A - S66.099S Other specified injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level
S66.190A - S66.199S Other injury of flexor muscle, fascia and tendon of finger at wrist and hand level
S66.291A - S66.299S Other specified injury of extensor muscle, fascia and tendon of thumb at wrist and hand level
S66.390A - S66.399S Other injury of extensor muscle, fascia and tendon of finger at wrist and hand level
S66.491A - S66.499S Other specified injury of intrinsic muscle, fascia and tendon of thumb at wrist and hand level
S66.590A - S66.599S Other injury of intrinsic muscle, fascia and tendon of index finger at wrist and hand level
S66.891A - S66.899S Other injury of other specified muscles, fascia and tendons at wrist and hand level
S66.991A - S66.999S Other injury of unspecified muscle, fascia and tendon at wrist and hand level
S76.091A - S76.099S Other specified injury of muscle, fascia and tendon of hip
S76.191A - S76.199S Other specified injury of quadriceps muscle, fascia and tendon
S76.291A - S76.299S Other injury of adductor muscle, fascia and tendon of thigh
S76.391A - S76.399S Other specified injury of muscle, fascia and tendon of the posterior muscle group at thigh level
S76.891A - S76.899S Other injury of other specified muscles, fascia and tendons at thigh level
S76.991A - S76.999S Other specified injury of unspecified muscles, fascia and tendons at thigh level
S86.091A - S86.099S Other specified injury of right tendon
S86.191A - S86.199S Other injury of other muscle(s) and tendon(s) of posterior muscle group at lower leg level
S86.291A - S86.299S Other injury of muscle(s) and tendon(s) of anterior muscle group at lower leg level
S86.391A - S86.399S Other injury of muscle(s) and tendon(s) of peroneal muscle group at lower leg level
S86.891A - S86.899S Other injury of other muscles and tendons at lower leg level [medial tibial stress syndrome]
S86.991A - S86.999S Other injury of unspecified muscle and tendon at lower leg level
S96.091A - S96.099S Other injury of muscle and tendon of long flexor muscle of toe at ankle and foot level
S96.191A - S96.199S Other specified injury of muscle and tendon of long extensor muscle of toe at ankle and foot level
S96.291A - S96.299S Other specified injury of intrinsic muscle and tendon at ankle and foot level
S96.891A - S96.899S Other specified injury of other specified muscles and tendons at ankle and foot level
S96.991A - S96.999S Other specified injury of unspecified muscle and tendon at ankle and foot level

The above policy is based on the following references:

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