Functional neuromuscular electrical stimulation (NMES) involves the use of a device that transmits electrical impulse to the skin over selected muscle groups by way of electrodes. There are two categories of NMES.  One is used to treat muscle atrophy and stimulates the muscle when the individual is in a resting state. The other, also known as functional electrical stimulation (FES), is used to enhance functional activity of neurologically impaired and spinal cord injured (SCI) patients.

H-wave stimulation is a form of electrical stimulation that differs from other forms of electrical stimulation, such as transcutaneous electrical nerve stimulation (TENS), in terms of its wave form. H-wave stimulation has been used for the treatment of pain related to a variety of etiologies, such as diabetic neuropathy, muscle sprains, temporomandibular joint dysfunctions, or reflex sympathetic dystrophy. H-wave stimulation has also been used to accelerate healing of wounds, such as diabetic ulcers.

Interferential stimulation is a type of electrical nerve stimulation that uses paired electrodes of two independent circuits carrying medium-frequency alternating currents. The electrodes are aligned on the skin so that the current flowing between each pair intersects at the underlying target. This maximizes the current permeating the tissues while minimizing unwanted stimulation of cutaneous nerves.

Use for Walking in Patients with Spinal Cord Injury (SCI)

A functional electrical stimulator (FES) for SCI (e.g, Parastep® Ambulation System) may be considered medically necessary for individuals with a diagnosis of paraplegia and who meet ALL of the following criteria:

• Individuals with intact lower motor units (L1 and below) (both muscle and peripheral nerve); and
• Individuals 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
• Individuals that demonstrate brisk muscle contraction to NMES; and
• Individuals that possess high motivation, commitment, and cognitive ability to use such devices for walking; and
• Individuals that can transfer independently and can demonstrate standing tolerance for at least three (3) minutes; and
• Individuals that can demonstrate hand and finger function to manipulate controls or have an attendant available that can manipulate the controls; and
• Individuals with at least six-month post recovery spinal cord injury and restorative surgery; and
• Individuals without severe, untreated hip and knee degenerative disease that prohibits them from the joint range of motion necessary for ambulation and no history of long bone fracture secondary to osteoporosis; and
• Individuals that have demonstrated a willingness to use the device long-term; and 
• Individuals with SCI must have completed a training program which consists of physical medicine sessions with the device, (Parastep® Ambulation System) over a period of three (3) months.

FES for SCI individuals is contraindicated for ANY ONE of the following:

• Cardiac pacemakers; or
• Severe scoliosis or severe osteoporosis; or
• Skin disease or cancer at the area of stimulation; or
• Irreversible contracture; or
• Autonomic dysreflexia triggered by FES or the ambulation system.

FES for SCI individuals not meeting the above criteria is considered not medical necessary. 

FES devices except for the Parastep System are considered experimental/investigational and therefore non-covered because the safety and/or effectiveness of this service cannot be established by the available published peer-reviewed literature.

Treatment of Muscle Atrophy

Functional neuromuscular electrical stimulation (NMES) may be considered medically necessary for treatment of disuse atrophy where nerve supply to the muscle is intact, including brain, spinal cord and peripheral nerves, and  other non-neurological reasons for disuse are causing atrophy.

• NOTE: Some examples would be casting or splinting of a limb, contracture due to scarring of soft tissue as in burn lesions, and hip replacement surgery (until orthotic training begins). NMES for any other indication is considered not medically necessary.

NMES for any other indication is considered not medically necessary.  

Multi-modality electrical stimulation device

Multi-modality electrical stimulation devices (i.g NexWave, Zynex) are considered experimental/investigational and therefore, non-covered, because the safety and/or effectiveness of this service cannot be established by the available published peer-reviewed literature.

 Supplies

Supplies for NMES may be considered medically necessary when the above criteria are met and with annual documentation in the individual’s medical record.

Supplies for multi-modality electrical stimulation devices (i.g Zynex Nexwave) is considered not medically necessary.  

Supplies for NMES for any other indication is considered not medically necessary.

Quantity level limits for supplies

Procedure code A4595 is allowed 12 every one (1) floating month.

Quantity of supplies that exceed the frequency guidelines listed on this policy are considered not medically necessary.

H-wave Electrical Stimulation

H-wave stimulation is considered experimental/investigational and therefore, non-covered, because the safety and/or effectiveness of this service cannot be established by the available published peer-reviewed literature. 

Interferential Stimulation

Interferential stimulation is considered experimental/investigational and therefore non-covered because the safety and/or effectiveness of this service cannot be established by the available published peer-reviewed literature.

NMES, H-wave Electrical Stimulation and Interferential Stimulators are typically outpatient procedures which are only eligible for coverage as an inpatient procedure in special circumstances, including, but not limited to, the presence of a co-morbid condition that would require monitoring in a more controlled environment such as the inpatient setting.