Ambulatory Assist Devices: Walkers, Canes, and Crutches

Number: 0505

Policy

Canes and Crutches

Aetna considers canes, quad canes, and crutches medically necessary durable medical equipment (DME) if all of the following criteria are met:

  1. Mobility Limitation

    The member has a mobility limitation that significantly impairs his/her ability to participate in one or more mobility-related activities of daily living (MRADL) in the home. The MRADLs to be considered in this and all other statements in this policy are toileting, feeding, dressing, grooming, and bathing performed in customary locations in the home. A mobility limitation is one that:
     
    1. Prevents the member from accomplishing the MRADL entirely; or
    2. Places the member at reasonably determined heightened risk of morbidity or mortality secondary to the attempts to perform an MRADL; or
    3. Prevents the member from completing the MRADL within a reasonable time frame; and

  2. The member is able to safely use the cane or crutch; and
  3. The functional mobility deficit can be sufficiently resolved by use of a cane or crutch.

Consistent with Medicare policy, Aetna does not consider axillary (under-arm), articulated, spring-assisted crutches medically necessary because the clinical value of these specialized crutches have not been established. An axillary (under-arm), articulated, spring-assisted crutch describes an articulating crutch which has two crutch legs connected by a bar between them which helps propel the member forward.

Aetna does not consider a sit-and-stand walking assistant type crutch medically necessary because its clinical value has not been established.

Note: Canes or crutches which contain a spring that reduces impact and vibration against the ground should be coded with the existing codes for canes or crutches.

Standard Walkers

Aetna considers a standard walker and related accessories medically necessary DME if all of the following criteria are met:

  1. Mobility Limitation

    The member has a mobility limitation that significantly impairs his/her ability to participate in one or more mobility-related activities of daily living (MRADL) in the home. A mobility limitation is one that:
     
    1. Prevents the member from accomplishing the MRADL entirely, or
    2. Places the member at reasonably determined heightened risk of morbidity or mortality secondary to the attempts to perform the MRADL, or
    3. Prevents the member from completing the MRADL within a reasonable time frame; and

  2. The member is able to safely use the walker; and
  3. The functional mobility deficit can be sufficiently resolved with use of a walker.

A standard walker may include wheels and glide-type brakes.  A wheeled walker is one with 2, 3, or 4 wheels.  The wheels may be fixed or swivel.  It may be fixed height or adjustable height.  It may or may not include glide-type brakes (or equivalent).

A glide-type brake consists of a spring mechanism (or equivalent), which raises the leg post of the walker off the ground when the member is not pushing down on the frame.

Pediatric Walkers and Crawlers

Aetna considers pediatric crawlers medically necessary DME for disabled children.

The Mulholland Walkabout is a walker with 4 wheels and attached back brace.  Aetna considers the Mulholland Walkabout medically necessary DME for children who have impaired ambulation and who lack trunk stability and balance.

Note: Aetna does not cover standard strollers because they do not meet Aetna's contractual definition of covered DME in that they are not primarily medical in nature and they are normally of use in the absence of illness or injury.

Specially adapted strollers may be considered medically necessary DME when they are used in place of a wheelchair for children.  See CPB 0271 - Wheelchairs and Power Operated Vehicles (Scooters).

Prone, Supine and Upright Standers for Children with Special Needs

These floor/mobile standers for children (e.g., Rifton Supine, Prone or Dynamic; Squiggles) are considered medically necessary DME for children with cerebral palsy or other severe neuromuscular conditions.

Heavy-Duty Walker

A heavy-duty walker is one that is labeled as capable of supporting members who weigh more than 300 pounds.  It may be fixed height or adjustable height.  It may be rigid or folding.  A heavy-duty walker is considered medically necessary DME for members who meet medical necessity criteria for a standard walker and who weigh more than 300 pounds.

A heavy-duty walker may include wheels and glide-type brakes.  A wheeled walker is one with 2, 3, or 4 wheels.  The wheels may be fixed or swivel.  It may be fixed height or adjustable height.  It may or may not include glide-type brakes (or equivalent).  A glide-type brake consists of a spring mechanism (or equivalent), which raises the leg post of the walker off the ground when the member is not pushing down on the frame.

Heavy-Duty, Multiple Braking System, Variable Wheel Resistance Walker

A heavy-duty, multiple braking system, variable wheel resistance walker is considered medically necessary DME for members who meet medical necessity criteria for a standard walker and who are unable to use a standard walker due to a severe neurological disorder or other condition causing the restricted use of one hand.  Obesity, by itself, is not considered a medically necessary indication for this walker.

Note: For purposes of this policy, a “heavy-duty, multiple braking system, and variable wheel resistance walker” is a 4-wheeled, adjustable height, folding-walker that has all of the following characteristics:

  1. At least 2 wheels have brakes that can be independently set through tension adjustability to give varying resistance, and
  2. Capable of supporting individuals who weigh greater than 350 pounds, and
  3. Hand operated brakes that cause the wheels to lock when the hand levers are released, and
  4. The hand brakes can be set so that either or both can lock the wheels, and
  5. The pressure required to operate each hand brake is individually adjustable, and
  6. There is an additional braking mechanism on the front crossbar

Walker with Enclosed Frame

Consistent with Medicare policy, Aetna does not cover walkers with enclosed frames because their medical necessity compared to a standard folding wheeled walker has not been established. A walker with enclosed frame is a folding wheeled walker that has a frame that completely surrounds the member and an attached seat in the back. 

Walker with Trunk Support

A walker with trunk support is considered medically necessary for members who meet medical necessity criteria for a standard walker and who have documentation in the medical record justifying the medical necessity for the special features.

Kneeling Walker/Knee Walker/RollingKnee Walker/ Kneeling Crutch

Aetna considers a kneeling walker/knee walker/rolling knee walker (e.g., Roll-A-Bout Walker, Rolleraid, Turning Leg Caddy) or a kneeling crutch (e.g., iWALKFree]) medically necessary DME for below-the-knee injuries/conditions if the member meets criteria for a standard walker, crutch or cane, but is unable to use one of those devices due to other impairments (e.g., member only has one functional arm, etc.).

Enhancement Accessories

Aetna does not cover enhancement accessories of walkers, canes and crutches as these are considered convenience items.  An enhancement accessory is one that does not contribute significantly to the therapeutic function of the walker, cane or crutch.  It may include, but is not limited to style, color, hand operated brakes (other than those described in the section above on heavy duty, multiple braking system, variable wheel resistance walker), seat attachments, tray attachments, baskets or cup holders (or equivalent).

Leg Extensions

Leg extensions are considered medically necessary DME for members 6 feet tall or more.

Arm Rests

Arm rest attachments are considered medically necessary DME when the member's ability to grip is impaired.

Walking Belts

Note: Aetna does not cover walking belts (belts used to support and guide the member in walking) because they do not meet Aetna's contractual definition of DME in that they are not primarily medical in nature and they are normally of use to persons who do not have a disease or injury.

Gait Trainers: The Rifton Gait Trainer/Pacer Gait Trainer, The KidWalk Gait Mobility System, and the Therapeutic Ambulatory Orthotic System (TAOS)

A gait trainer (or sometimes referred to as a rollator) is a term used to describe certain devices that are used to support a member during ambulation.

Aetna considers the Rifton Gait Trainer/Pacer Gait Trainer medically necessary DME for children and adults with cerebral palsy or other neuromuscular disorders who require moderate to maximum support for walking and who are capable of walking with this device.

The Rifton Gait Trainer is a type of walker, which provides considerable postural support for the user.  It comes in a range of sizes that caters for tiny children through to adults.  Each size has a range of adjustable features that can be adjusted to meet individual needs.  This walker has been superseded by the Pacer Gait Trainer, which is a redesign of the Rifton Gait Trainer.  It is suitable for children and adults who require moderate to maximum support for walking.  The frame is made of aluminum.  The large casters offer a range of functions -- gradual brake/drag, brake lock, swivel, swivel lock and 1-way ratchet control.  This gives a wide range of control in speed, direction and maneuverability.  Three sizes are available -- user elbow heights from 44.5 to 119.5 cm.

Aetna considers the KidWalk Gait Mobility System and the Therapeutic Ambulatory Orthotic System (TAOS) medically necessary DME for children with cerebral palsy or other neuromuscular disorders who require moderate to maximum support for walking and are capable of walking with these devices.

The TAOS is an orthotic and a walker base.  According to the manufacturer, these 2 components work together to provide a child with cerebral palsy an upright hands-free environment.  The manufacturer states that the orthotic guides the child into proper alignment so they can train the proper muscles.  The base holds the child in a standing position and provides security for them to explore and improve.

Wearable Freezing of Gait Detection System

Aetna considers the use of a wearable freezing of gait detection system for assisting walking of individuals with Parkinson's disease experimental and investigational because of insufficient evidence in the peer-reviewed literature.

Autoambulators

Aetna considers the Autoambulator experimental and investigational because the clinical evidence is not sufficient to permit conclusions on the health outcome effects of the Autoambulator. 

Background

This policy is based, in part, upon Medicare DME MAC Local Medical Policy.

Approximately 50 % of the patients with advanced Parkinson's disease (PD) suffer from freezing of gait (FOG), which is a sudden and transient inability to walk.  It often causes falls, interferes with daily activities and significantly impairs quality of life.  Because gait deficits in PD patients are often resistant to pharmacotherapies, effective non-pharmacotherapiess are of special interest.  Bachlin and colleagues (2010) evaluated the concept of a wearable device that can obtain real-time gait data, processes them and provides assistance based on pre-determined specifications.  This wearable system uses on-body acceleration sensors to measure the patients' movements.  It automatically detects FOG by analyzing frequency components inherent in these movements.  When FOG is detected, the assistant provides a rhythmic auditory signal that stimulates the patient to resume walking.  These investigators evaluated their wearable assistive technology in a study with 10 PD patients.  Over 8 hours of data were recorded and a questionnaire was filled out by each patient.  A total of 237 FOG events have been identified by professional physiotherapists in a post-hoc video analysis.  The device detected the FOG events online with a sensitivity of 73.1 % and a specificity of 81.6 % on a 0.5-sec frame-based evaluation.  The authors concluded that these findings showed that online assistive feedback for PD patients is possible.  They stated that their results demonstrated the benefit of such a context-aware system and motivated further studies.

The Autoambulator

The Autoambulator is a therapeutic robotic machine developed to rehabilitate individuals recovering from conditions affecting walking such as stroke, spinal cord injury, and hip or knee replacement surgery.  The AutoAmbulator features an overhead harness system to fully support the patient, mechanically powered braces to move the patient's legs, and numerous computerized sensors to track vital signs, movement, and contact speed, adjusting speed accordingly.  Researchers are evaluating the AutoAmbulator's ability to increase blood flow in patients' legs, decrease muscle spasms, and improve respiration and circulatory function.

Schmidt et al (2007) stated that gait restoration is an integral part of rehabilitation of brain lesioned patients. Modern concepts favor a task-specific repetitive approach, i.e., who wants to regain walking has to walk, while tone-inhibiting and gait preparatory maneuvers had dominated therapy before.  Following the first mobilization out of the bed, the wheelchair-bound patient should have the possibility to practice complex gait cycles as soon as possible.  Steps in this direction were treadmill training with partial body weight support and most recently gait machines enabling the repetitive training of even surface gait and even of stair climbing.  With treadmill training harness-secured and partially relieved wheelchair-mobilized patients could practice up to 1,000 steps per session for the first time.  Controlled trials in stroke and spinal cord injured (SCI) patients, however, failed to show a superior result when compared to walking exercise on the floor.  Most likely explanation was the effort for the therapists, e.g., manually setting the paretic limbs during the swing phase resulting in a too little gait intensity.  The next steps were gait machines, either consisting of a powered exoskeleton and a treadmill (Lokomat, AutoAmbulator) or an electro-mechanical solution with the harness secured patient placed on movable foot plates (Gait Trainer GT I).  For the latter, a large multi-center trial with 155 non-ambulatory stroke patients (DEGAS) revealed a superior gait ability and competence in basic activities of living in the experimental group.  The HapticWalker continued the end effector concept of movable foot plates, now fully programmable and equipped with 6 degree of freedom (DOF) force sensors.  This device for the first time enabled training of arbitrary walking situations, hence not only the simulation of floor walking but also for example of stair climbing and perturbations.  The authors concluded that locomotor therapy is a fascinating new tool in rehabilitation, which is in line with modern principles of motor relearning promoting a task-specific repetitive approach.  Moreover, they stated that sophisticated technical developments and positive randomized controlled trials (RCTs) form the basis of a growing acceptance worldwide to the benefits of stroke and SCI patients.

In a systematic review, Swinnen and colleagues (2014) summarized the improvements in balance after robot-assisted gait training (RAGT) in stroke patients; PubMed and Web of Knowledge were searched. The most important words were "stroke", "RAGT", "balance", "Lokomat" and "gait trainer".  Studies were included if stroke patients were involved in RAGT protocols, and balance was determined as an outcome measurement.  The articles were checked for methodological quality by 2 reviewers (Cohen's κ = 0.72).  A total of 9 studies were included (7 true experimental and 2 pre-experimental studies; methodological quality score, 56 % to 81 %).  In total, 229 sub-acute or chronic stroke patients (70.5 % male) were involved in RAGT (3 to 5 times per week, 3 to 10 weeks, 12 to 25 sessions).  In 5 studies, the gait trainer was used; in 2, the Lokomat was used; in 1 study, a single-joint wearable knee orthosis was used; and in 1 study, the AutoAmbulator was used.  A total of 8 studies compared RAGT with other gait rehabilitation methods.  Significant improvements (no to large effect sizes, Cohen's d = 0.01 to 3.01) in balance scores measured with the Berg Balance Scale, the Tinetti test, postural sway tests, and the Timed Up and Go test were found after RAGT.  No significant differences in balance between the intervention and control groups were reported.  Robot-assisted gait training can lead to improvements in balance in stroke patients; however, it is not clear whether the improvements are greater compared with those associated with other gait rehabilitation methods.  The authors concluded that because a limited number of studies are available, more specific research (e.g., RCTs with larger, specific populations) is needed to draw stronger conclusions.

According to Winchester and Querry (2006), robotic orthoses for body weight-supported treadmill training (BWSTT) has become an accepted standard of care in gait rehabilitation methods.  This type of locomotor training has many functional benefits, but the physical labor costs are considerable.  To reduce therapist effort and improve the repeatability of locomotor training, 3 groups have developed commercially available robotic devices for assisted stepping.  The purpose of these robotic devices is to augment locomotor rehabilitation by decreasing therapist manual assistance, increasing the amount of stepping practice, while decreasing therapist effort.  Current clinical studies have yielded positive and promising results in locomotor rehabilitation inpatients with neurologic impairments of stroke or spinal cord injury.  The potential benefits from robotic technology are significant for clinical use and research.  As further research is conducted, rehabilitation therapists and patient outcomes will be able to contribute to the development of current and future technologies.

Wearable Freezing of Gait Detection System

Jovanov et al (2009) stated that freezing of gait (FOG) is a common complication in movement disorders, typically associated with the advanced stages of Parkinson's disease (PD). Auditory cues might be used to facilitate unfreezing of gait and prevent fall related injuries.  These investigators presented a wearable, unobtrusive system for real-time gait monitoring, which consists of an inertial wearable sensor and wireless headset for the delivery of acoustic cues.  The system recognizes FOG episodes with minimum latency and delivers acoustic cues to unfreeze the gait.  They presented design of a system for the detection and unfreezing of gait (deFOG), and preliminary results of the feasibility study.  In a limited test run of 4 test cases, the system was able to detect FOG with average latency of 332 ms, and maximum latency of 580 ms.

Coste et al (2014) noted that FOG is a common symptom in patients with PD, which affects the gait pattern and is associated to a fall risk. Automatized FOG episode detection would allow systematic assessment of patient state and objective evaluation of the clinical effects of treatments.  Techniques have been proposed in the literature to identify FOG episodes based on the frequency properties of inertial sensor signals.  These researchers adapted and extended these FOG detectors in order to include other associated gait pattern changes, like festination.  The proposed approach was based on a single wireless inertial sensor placed on the patient's lower limbs.  The preliminary experimental results showed that existing frequency-based freezing detectors are not sufficient to detect all FOG and festination episodes and that the observation of some gait parameters such as stride length and cadence are valuable inputs to anticipate the occurrence of upcoming FOG events.

Appendix

The item in Column II is included in the allowance for the corresponding item in Column I when provided at the same time and must not be billed separately at the time of billing the item in Column.

Walker Billing Details
Ambulatory Assist devices Items covered in Assist Devices
  • WALKER,
  • RIGID (PICKUP),
  • ADJUSTABLE OR FIXED HEIGHT 
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH 
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WALKER,
  • FOLDING (PICKUP),
  • ADJUSTABLE OR FIXED HEIGHT
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH. 
  • WALKER,
  • WITH TRUNK SUPPORT,
  • ADJUSTABLE OR FIXED HEIGHT,
  • ANY TYPE
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH. 
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH
  • WALKER,
  • RIGID,
  • WHEELED,
  • ADJUSTABLE OR FIXED HEIGHT
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH
  • WALKER,
  • FOLDING,
  • WHEELED,
  • ADJUSTABLE OR FIXED HEIGHT
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH
  • WALKER,
  • ENCLOSED,
  • FOUR SIDED FRAMED,
  • RIGID OR FOLDING,
  • WHEELED WITH POSTERIOR SEAT
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH
  • SEAT ATTACHMENT,
  • WALKER 
  • WALKER,
  • HEAVY DUTY,
  • MULTIPLE BRAKING SYSTEM,
  • VARIABLE WHEEL RESISTANCE
 
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH
  • WALKER,
  • HEAVY DUTY,
  • WITHOUT WHEELS,
  • RIGID OR FOLDING,
  • ANY TYPE,
  • EACH
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WALKER,
  • HEAVY DUTY,
  • WHEELED,
  • RIGID OR FOLDING,
  • ANY TYPE
  • REPLACEMENT,
  • HANDGRIP,
  • CANE,
  • CRUTCH,
  • OR WALKER,
  • EACH
  • REPLACEMENT,
  • TIP,
  • CANE,
  • CRUTCH,
  • WALKER,
  • EACH.
  • WHEEL ATTACHMENT,
  • RIGID PICK-UP WALKER,
  • PER PAIR
  • BRAKE ATTACHMENT FOR WHEELED WALKER,
  • REPLACEMENT,
  • EACH 
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 "+":

HCPCS codes covered if selection criteria are met:

A4635 Underarm pad, crutch, replacement, each
A4636 Replacement, handgrip, cane, crutch, or walker, each
A4637 Replacement, tip, cane, crutch, or walker, each
E0100 Cane, includes canes of all materials, adjustable or fixed, with tip
E0105 Cane, quad or three-prong, includes canes of all materials, adjustable or fixed, with tips
E0110 Crutches, forearm, includes crutches of various materials, adjustable of fixed, pair, complete with tips and handgrips
E0111 Crutch, forearm, includes crutches of various materials, adjustable or fixed, each, with tip and handgrip
E0112 Crutches, underarm, wood, adjustable or fixed, pair, with pads, tips and handgrips
E0113 Crutch, underarm, wood, adjustable or fixed, each, with pad, tip and handgrip
E0114 Crutches, underarm, other than wood, adjustable or fixed, pair, with pads, tips and handgrips
E0116 Crutch, underarm, other than wood, adjustable or fixed, with PAD, tip, handgrip, with or without shock absorber, each
E0118 Crutch substitute, lower leg platform, with or without wheels, each [iWalkFree]
E0130 Walker, rigid (pick-up), adjustable or fixed height
E0135 Walker, folding (pickup), adjustable or fixed height
E0140 Walker, with trunk support, adjustable or fixed height, any type
E0141 Walker, rigid, wheeled, adjustable or fixed height
E0143 Walker, folding, wheeled, adjustable or fixed height
E0147 Walker, heavy duty, multiple braking system, variable wheel resistance
E0148 Walker, heavy duty, without wheels, rigid or folding, any type, each
E0149 Walker, heavy duty, wheeled, rigid or folding, any type
E0153 Platform attachment, forearm crutch, each
E0154 Platform attachment, walker, each
E0155 Wheel attachment, rigid pick-up walker, per pair seat attachment, walker
E0157 Crutch attachment, walker, each
E0158 Leg extensions for walker, per set of four (4)
E0159 Brake attachment for wheeled walker, replacement, each
E0638 Standing frame system, one position (e.g., upright, supine or prone stander), any size including pediatric, with or without wheels
E0641 Standing frame system, multi-position (e.g., three way stander), any size including pediatric, with or without wheels
E0642 Standing frame system, mobile (dynamic stander), any size including pediatric
E1031 Rollabout chair, any and all types with castors 5” or greater [Rolleraid]
E8000 Gait trainer, pediatric size, posterior support, includes all accessories and components
E8001 Gait trainer, pediatric size, upright support, includes all accessories and components
E8002 Gait trainer, pediatric size, anterior support, includes all accessories and components

HCPCS codes not covered for indications listed in the CPB:

Sit-and-stand walking assistant crutch - no specific code:

E0117 Crutch, underarm, articulating, spring assisted, each
E0144 Walker, enclosed, four sided framed, rigid or folding, wheeled with posterior seat
E0156 Seat attachment, walker

ICD-10 codes:

Too many to list.

The above policy is based on the following references:

  1. U.S. Department of Health and Human Services, Health Care Financing Administration (HCFA). Medicare Coverage Issues Manual §§60-3, 60-9, 60-15. Baltimore, MD; HCFA; 1999.
  2. Lehman JF, Lateur BJ. Gait analysis. Diagnosis and management. In: Krusen's Handbook of Physical Medicine and Rehabilitation. 4th ed. FJ Kottke, JF Lehmann, eds. Philadelphia, PA: WB Saunders Co.; 1990; Ch. 4:108-125.
  3. Ragnarsson KT. Lower extremity orthotics, shoes, and gait aids. In: Rehabilitation Medicine: Principles and Practice. 2nd ed. JA DeLisa, ed. Philadelphia, PA: JB Lippincott Co.; 1993: Ch. 23:492-506.
  4. Kling C, Persson A, Gardulf A. The ADL ability and use of technical aids in persons with late effects of polio. Am J Occup Ther. 2002;56(4):457-461.
  5. Van Hook FW, Demonbreun D, Weiss BD. Ambulatory devices for chronic gait disorders in the elderly. Am Fam Physician. 2003;67(8):1717-1724.
  6. Roll-A-Bout Corporation. Roll-A-Bout Walker [website]. Frederica, DE: Roll-A-Bout Corporation; 2002. Available at: http://www.roll-a-bout.com/. Accessed April 22, 2003.
  7. Community Products, LLC. Rifton Equipment [website]. Chester, NY: Community Products; 2004. Available at: http://www.rifton.com/rifton/pacer.htm. Accessed July 12, 2004.
  8. NHIC, Corp. Canes and crutches. Local Coverage Determination No. L11496. Durable Medical Equipment Medicare Administrative Contractor (DME MAC) Jurisdiction A. Hingham, MA: NHIC; revised October 31, 2014.
  9. NHIC, Corp. Canes and crutches. Policy Article No. A23660. Durable Medical Equipment Medicare Administrative Contractor (DME MAC) Jurisdiction A. Hingham, MA: NHIC; revised April 1, 2013.
  10. NHIC, Corp. Walkers. Local Coverage Determination No. L11472. Durable Medical Equipment Medicare Administrative Contractor (DME MAC) Jurisdiction A. Hingham, MA: NHIC; revised October 31, 2014.
  11. NHIC, Corp. Walkers. Policy Article No. A35351. Durabe Medical Equipment Medicare Administrative Contractor (DME MAC) Jurisdiction A. Hingham, MA: NHIC; revised November 1, 2013.
  12. Southwest Medical LLC. Gait trainers [website]. Phoenix, AZ: Southwest Medical; 2010. Available at: http://www.southwestmedical.com/category/Gait-Trainers/460. Accessed May 14, 2010.
  13. Bachlin M, Plotnik M, Roggen D, et al. A wearable system to assist walking of Parkinson's disease patients. Methods Inf Med. 2010;49(1):88-95.
  14. Winchester P; Querry R. Robotic orthoses for body weight-supported treadmill training. Phys Med Rehabil Clin N Am. 2006;17(1):159-172.
  15. Centers for Medicare & Medicaid Services (CMS). National Coverage Determination (NCD) for Durable Medical Equipment Reference List (280.1). Baltimore, MD: CMS; effective July 5, 2005.
  16. Schmidt H, Werner C, Bernhardt R, et al. Gait rehabilitation machines based on programmable footplates. J Neuroeng Rehabil. 2007;4:2.
  17. Jovanov E, Wang E, Verhagen L, et al. deFOG -- A real time system for detection and unfreezing of gait of Parkinson's patients. Conf Proc IEEE Eng Med Biol Soc. 2009;2009:5151-51544.
  18. Swinnen E, Beckwée D, Meeusen R, et al. Does robot-assisted gait rehabilitation improve balance in stroke patients? A systematic review. Top Stroke Rehabil. 2014;21(2):87-100.
  19. Coste CA, Sijobert B, Pissard-Gibollet R, et al. Detection of freezing of gait in Parkinson disease: Preliminary results. Sensors (Basel). 2014;14(4):6819-6827.