Medical Policy: 01.01.23
Original Effective Date: November 2000
Reviewed: November 2014
Revised: November 2014
Benefit determinations are based on the applicable contract language in effect at the time the
services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary
based on contract, and individual member benefits must be verified. Wellmark determines medical
necessity only if the benefit exists and no contract exclusions are applicable. This medical
policy may not apply to FEP. Benefits are determined by the Federal Employee Program.
This Medical Policy document describes the status of medical technology at the time the document
was developed. Since that time, new technology may have emerged or new medical literature may
have been published. This Medical Policy will be reviewed regularly and be updated as scientific
and medical literature becomes available.
Neuromuscular electrical stimulation (NMES) involves the use of a device that transmits an electrical impulse to the skin over selected muscle groups by way of electrodes. There are two categories of NMES. One type of NMES device is used to treat muscle atrophy and stimulates the muscle when the individual is at a resting state. The second type, is also known as functional neuromuscular stimulation (FNS) or functional electrical stimulation (FES), which is used to enhance functional activity (e.g., grasping utensils for feeding or ambulation) of neurologically impaired individuals.
Functional Neuromuscular Stimulation (FNS) or functional electrical stimulation (FES) is a rehabilitation technology that uses low-voltage electrical impulses to evoke a peripheral nerve action potential, which in turn causes a skeletal muscle response. The use of FNS/FES has primarily been proposed for individuals with neurological conditions such as spinal cord injury (SCI), multiple sclerosis, cerebrovascular accident (CVA), and cerebral palsy (CP).
One of the applications of FNS/FES is to provide individuals with a spinal cord injury with the ability to stand and walk. The device delivers a precise sequence of electrical pulses to trigger action potential at selected nerves at the quadriceps (for knee extension), common peroneal nerve (for hip flexion), and the paraspinals and gluteals (for trunk stability). The individual uses a walker or elbow support crutches for further support. The electrical impulses are controlled by a computer microchip attached to the individual’s belt that synchronizes and distributes the signals. Additionally, there is a finger controlled switch that permits activation of the stepping by the individual. The Parastep® Ambulation System (Therapeutic Alliances, Inc, Fairborn, OH) is the only device to receive approval by the FDA and is indicated to “enable appropriately selected skeletally mature spinal cord injured patients (C6-T12) to stand and attain limited ambulation and/or management of spinal cord injury.”
How the Parastep System Works
The Parastep® Ambulation System works by delivering microcomputer-controlled electrical pulses through surface (skin) applied electrodes to nerves and muscles, causing muscle contractions. The computer is programmed to control the sequence of muscle contractions in the lower extremities that enable the functions of sit-to-stand, right and left step, and stand-to-sit. Users are taught to initiate functions by activating commands through switch modules mounted on the walker.
The system is designed to provide up to 6 channels of stimulation (i.e. stimulate up to 3 muscle groups on each leg/side). However, some individuals may require only 4 channels of stimulation to stand and ambulate.
- When 4 channels are used, electrical stimulation is directed to 4 electrodes on each lower extremity:
- Stimulation of the quadriceps muscles results in knee extension, enabling the use to stand.
- Stimulation of the peroneal nerve in the lower extremity initiates a triple-flexion reflex response, resulting in contraction of muscles to flex the hip, knee and ankle, which lifts the foot off the floor.
- Subsequent quadriceps stimulation extends the knee in preparation for heel-strike and weight bearing.
- When 6 channels of stimulation are used, electrical stimulation is directed to the previously mentioned sites above and to two additional electrodes on the hip.
- Stimulation of gluteal muscles extends the hips, contributing to stability while standing and taking steps.
The user initiates and controls the intensity of stimulation to the muscles and nerves through the keypad on the stimulator/control unit or through two switch modules mounted on the walker handle bars. The walker provides balance and stability during standing and walking.
Physical therapy is a key component to the Parastep® Ambulation System. Thirty-two sessions of physical therapy including instruction on system use and gait training, are provided to users when they purchase a system. The training is provided by hospital based physical therapists who have completed Sigmedics, Inc.’s clinical training program.
Each user’s progress is carefully monitored with frequent adjustments made in the training program to accomadate each user’s individual requirements. Treatment sessions progress at a pace set by each user’s ability, skill and proficiency.
To acquire a Parastep® Ambulation System an individual must participate in an approved Parastep® clinical training program and obtain a physicians prescription.
Other functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) devices have been developed for individuals with foot drop. Foot drop is caused by weakness in the foot and ankle, which is activated by the peroneal nerve that results in a decreased dorsiflexion and causes difficulty with ambulation. It can be caused by neurological conditions that include spinal cord injury (SCI), multiple sclerosis (MS), cerebrovascular accident (CVA) and cerebral palsy (CP). WalkAide® and the Bioness NESS L300TM (Innovative Neurotronics, Inc., Bethesda, MD) are examples of FES devices for foot drop.
The NESS L300TM consists of three components: a functional stimulation cuff is worn by the individual by the individual just below the knee and holds the stimulation device and electrodes. The gait sensor is worn inside the individuals shoe and automatically detects different walking speeds and surface and sends a signal to the functional stimulation cuff to adjust the stimulation to the peroneal nerve to allow the individual’s gait to be adjusted. The control device allows the individual to turn the NESS L300TM on and off, as well as make stimulation adjustments.
There have been small studies that have focused on FNS/FES devices for foot drop. However, these studies did not demonstrate that the use of such devices provide a clinically significant improvement in ambulation. Studies with a larger number of individuals over a longer duration are needed to permit conclusions concerning the safety and effectiveness of this technology on health outcomes in individuals with foot drop (gait disturbances).
Another application of FNS/FES is to restore upper extremity functions such as grasp-release in individuals with CVA or SCI. An example of FES device for the upper extremity is the NESS H200TM (Innovative Neurotronics, Inc., Bethesda, MD). It consists of two components, an orthosis and a control device. The orthosis fits on the individual’s hand and forearm and maintains the wrist in position to perform functional hand movements. It has electrodes that are in direct contact with the individuals forearm muscles. The control device has microprocessor that sends electrical impulses from the control device to the electrodes and stimulates the forearm muscles, causing muscle activation and the ability to pinch, grasp, and release. Based on the peer reviewed literature, the evidence for the use of FNS/FES devices for upper extremity function is limited by a small number of subjects and limited data demonstrating the clinical utility outside the clinical setting. The available evidence is insufficient to conclude the safety and effectiveness that FNS/FES improves health outcomes of providing upper extremity function.
Neuromuscular Electrical Stimulation (NMES)
Neuromuscular electrical stimulation (NMES) is used as a treatment modality for disuse atrophy due to a conditions such as limb casting, contractures due to scarring of soft tissues or hip replacement surgery, where the nerve supply to the muscle is intact.
Disuse atrophy is another term for muscle atrophy, or muscle wasting. It occurs when a muscle is no longer as active as usual. When muscles are no longer in use, they slowly become weaker. Eventually, they begin to shrink. In some cases, disuse atrophy can be reversed if the muscles become active again.
NMES device is a portable stimulator with electrodes that are placed on the skin over a targeted muscle or muscle group. The current passes through the electrodes into the body, and the motor nerves are stimulated causing a muscle contraction. The intensity and frequency of the stimulation can vary based on the level of muscular function and repose to the treatment.
The use of NMES has been studied in cases where the neural supply (brain, spinal cord and peripheral nerves) to the muscle were intact or where other non-neurological reasons for disuse were causing atrophy. Based on the studies and literature, the use of NMES for the treatment of disuse atrophy is considered effective therapy when the cause of the muscle disuse is not permanent and there is no nervous system involvement. The treatment of disuse atrophy typically leads to a full recovery of function.
The Neurocontrol Freehand system received approval from the U.S. Food and Drug Administration (FDA) in 1997 through the premarket approval (PMA) process. The Handmaster NMS I system was originally cleared for use in maintaining or improving range of motion, reducing muscle spasm, preventing or retarding muscle atrophy, providing muscle re-education, and improving circulation; in 2001, its 510(k) marketing clearance was expanded to include provision of hand active range of motion and function for patients with C5 tetraplegia.
The WalkAide device first received 510(k) marketing clearance from FDA in the 1990s; the current version of the WalkAide device received 510(k) marketing clearance in September 2005. The Odstock Foot Drop Stimulator received 510(k) marketing clearance in 2005. The Bioness NESS L300 received 510(k) marketing clearance in July 2006. FDA summaries for the devices state that they are intended to be used in patients with drop foot by assisting with ankle dorsiflexion during the swing phase of gait.
To date, the Parastep® Ambulation System is the only noninvasive functional walking neuromuscular stimulation device to receive PMA from FDA. The Parastep device is approved to “enable appropriately selected skeletally mature spinal cord injured patients (level C6-T12) to stand and attain limited ambulation and/or take steps, with assistance if required, following a prescribed period of physical therapy training in conjunction with rehabilitation management of spinal cord injury.”
Functional Neuromuscular Stimulation (FNS)/Functional Electrical Stimulation (FES) Lower Extremities
Functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) (e.g, Parastep® Ambulation System) may be considered medically necessary to enable members with spinal cord injury (SCI) to ambulate when all of the following criteria are met:
- Persons with intact lower motor units (L1 and below) (both muscle and peripheral nerve); and
- Persons with muscle and joint stability for weight bearing at upper and lower extremities that can demonstrate balance and control to maintain an upright support posture independently; and
- Persons that demonstrate brisk muscle contract to FNS and have sensory perception of electrical stimulation sufficient for muscle contraction; and
- Persons that possess high motivation, commitment and cognitive ability to use such device for walking; and
- Persons that can transfer independently and can demonstrate standing tolerance for at least 3 minutes; and
- Persons that can demonstrate hand and finger function to manipulate controls; and
- Persons with at least 6-month post recovery spinal cord injury and restorative surgery; and
- Persons without hip and knee degenerative disease and no history of long bone fracture secondary to osteoporosis; and
- Persons that have demonstrated a willingness to use the device long term.
In addition to meeting all the above criteria, individuals with spinal cord injury (SCI) must have completed physical therapy (PT) training with the Parastep® Ambulation System. A physical therapy evaluation may be requested as part of any medical necessity review determination.
Individuals with a spinal cord injury (SCI) with the following conditions would not be considered candidates for the functional nerve stimulation (FNS)/functional electrical stimulation (FES) (e.g. Parastep® Ambulation System):
- Individuals with cardiac pacemaker; or
- Individuals with severe scoliosis or severe osteoporosis; or
- Individuals with skin disease or cancer at area of stimulation; or
- Individuals with irreversible contracture; or
- Individuals with autonomic dysreflexia
Functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) for indicationsother than listed above as medically necessary is considered investigational. Based on the peer reviewed literature there is insufficient evidence demonstrating the devices impact on safety and effectiveness on health outcomes for any other indications.
Functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES)/functional electrical stimulation (FES) devices developed for individuals with foot drop (gait disorders) (e.g. WalkAide® and NESS L300TM) is considered investigational for all indications including but not limited to the following:
- Spinal cord injury (SCI)
- Stroke/cerebrovascular accident (CVA)
- Multiple sclerosis (MS)
- Cerebral Palsy (CP)
Based on the peer reviewed literature there is insufficient evidence that the use of functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) will improve health outcomes in patients with gait disorders (foot drop). Published studies are of small patient populations, short term follow-ups, and various treatment protocols, outcome measures and FES devices. Further studies are needed to permit conclusions concerning the safety and effectiveness of this devices on health outcomes. Therefore, FNS/FES is considered investigational for all indications for the treatment of gait disorders (foot drop).
Functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) of the upper extremities (e.g. NESS H200TM) is considered investigational for all indications including but not limited to the following:
- Spinal cord injury (SCI)
- Stroke/cerebrovascular accident (CVA)
- Traumatic brain injury
- Other upper motor neuron disorders (e.g. Parkinson’s disease)
Based on the peer reviewed literature, the evidence for the use of FNS/FES devices for upper extremity function is limited by a small number of subjects and limited data demonstrating the clinical utility outside the clinical setting. The available evidence is insufficient to conclude that FNS/FES improves health outcomes of providing upper extremity function and the safety and/or effectiveness cannot be established and therefore is considered investigational.
Neuromuscular Electrical Stimulation (NMES)
Neuromuscular Electrical Stimulation (NMES) may be considered medically necessary for disuse atrophy where the nerve supply to the muscle is intact and the member has any of the following non-neurological reasons for disuse atrophy:
- Previous casting or splinting of a limb
- Contractures due to scarring of soft tissue (e.g. burn scarring)
- Major knee surgery (e.g. total knee replacement) with failure to respond to physical therapy
- Hip replacement prior to initiation of physical therapy
Neuromuscular Electrical Stimulation (NMES) for all other indications for disuse atrophy, including use where the nerve supply to the muscle is not intact, are considered investigational and, therefore, not covered because their safety and/or efficacy cannot by established by review of the available published peer-reviewed literature.
Procedure Codes and Billing Guidelines:
- Neuromuscular Electrical Stimulation (NMESTo report provider services, use appropriate CPT* codes, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.
- E0745 Neuromuscular stimulator, electronic shock unit
- E0764 Functional neuromuscular stimulation, transcutaneous stimulation of sequential muscle groups of ambulation with computer control, used for walking by spinal cord injured, entire system, after completion of training program.
- E0770 Functional electrical stimulator, transcutaneous stimulation of nerve and/or muscle groups, any type, complete system, not otherwise specified.
Wellmark's policy is based on:
- Hooker, SP, et al. Physiologic response to prolonged electrically stimulated leg-cycle exercise in the spinal cord injured. Archives of Physical Medicine and Rehabilitation 1990; vol 71: 863-869.
- BeDell, KK, et al. Effects of functional electrical stimulation-induced lower extremity cycling on bone density of spinal cord-injured patients. American Journal of Physical Medicine and Rehabilitation, 1996; 75:29-34.
- Yan T, Hui-Chan CW, Li LS. Functional electrical stimulation improves motor recovery of the lower extremity and walking ability of subjects with first acute stroke: a randomized placebo-controlled trial. Stroke 2005;36(1):80-5.
- U.S. Food and Drug Administration (FDA), Medical Devices Database, Sigmedics, INC. Parastep FES Unit. P900038.
- CMS National Coverage Determination: Decision Memo for Neuromuscular Electrical Stimulation (NMES) for Spinal Cord Injury (CAG-00153R).
- Sigmedics, INC. The Parastep I System.
- Yale Journal of Biology and Medicine 85 (2012), pp. 201-215.Neuromuscular Electrical Stimulation for Skeletal Function. Barbara M. Doucet, Amy Lam, and Lisa Griffin.
- National Multiple Sclerosis Society, Functional Electrical Stimulation (FES).
- ECRI. Hotline Response. Neuromuscular Electrical Stimulation for Improving Mobility and Motor Function Following Spinal Cord Injury. July 2012. www,ecri.org
- ECRI. Neuromuscular Electrical Stimulation for Hemiplgia. Plymouth Meeting (PA): ECRI Health Technology Information Service; 2008 October 10. 16 p. (ECRI Hotline Response).
- American Academy of Orthopaedic Surgeons, Second Look, Exercise Benefits Total Knee Arthroplasty and NMES.
- J Orthop Sports Phys Ther. 2004 Jan;34(1):21-9. Neuromuscular Electrical Stimulation for Quadriceps Muscle Strengthening after Bilateral Total Knee Arthroplasty: A Case Series. Department of Physical Therapy, University of Florida.
- Physical Therapy February 2012 vol. 92 no. 2 210-226. Early Neuromuscular Electrical Stimulation to Improve Quadriceps Muscle Strength After Total Knee Arthroplasty: A Randomized Controlled Trial. Ptjournal.apta.org
- Journal of Orthopaedic & Sports Physical Therapy. Volume 40. Number 7. July 2010. Effects of Neuromuscular Electrical Stimulation After Anterior Cruciate Ligament Reconstruction on Quadriceps Strength, Function, and Patient Oriented Outcomes: A Systemic Review.
- CMS National Coverage Determination for Neuromuscular Electrical Stimulation (NMES) (160.2)
- CMS Decision Memo for Neuromuscular Electrical Stimulation for Spinal Cord Injury (CAG-00153R), July 22, 2002.
- G. Monroe, A, Fusco. et. al., Clinical Study Walking Training with Foot Drop Stimulator Controlled by a Tilt Sensor to Improve Walking Outcomes: A Randomized Controlled Pilot Study in Patients with Stroke in Subacute Phase. Stroke Research and Treatment,Volume, doi:10.1155/2012/523564.
- National Institute of Health (NIH), published in final edited form as: Neurorehabil Neural Repair. 2013 March; 27(3):200-207. Doi.10.1177/154596831246716. Diane L. Damjano, PhD, Laura A. Prosser, PhD, et. al. Muscle Plasticity and Ankle Control after Repetitive use of a Functional Electrical Stimulation Device for Foot Drop in Cerebral Palsy.
- Sasha M. Scott, et. al. Quantification of Gait Kinematics and Walking Ability of People with Multiple Sclerosis who are New Users of Functional Electrical Stimulation. J Rehabil Med 2013:45:364-369.
Date Reason Action
October 2010 Annual review Policy renewed
February 2011 Interim review Policy revised
January 2012 Annual review Policy renewed
January 2013 Annual review Policy renewed
January 2014 Annual review Revised and new policy created
November 2014 Annual review Policy revised
Wellmark medical policies address the complex issue
of technology assessment of new and emerging treatments, devices,
drugs, etc. They are developed to
assist in administering plan benefits and constitute neither offers of
coverage nor medical advice. Wellmark medical policies contain only a
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and, therefore, cannot guarantee any results or outcomes.
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and therefore are subject to change without notice.
*Current Procedural Terminology © 2012 American Medical Association. All Rights Reserved.