Parastep I ™ FAQ

The Parastep I™ System comes from the medical engineering sciences known as neuroprosthetics. The Parastep I™ System is a microcomputer controlled functional neuromuscular stimulation (FNS) system that enables independent, unbraced ambulation (i.e., standing and walking) by people with a spinal cord injury.

The Parastep is a non-invasive system and consists of the following components:

  • a microcomputer controlled neuromuscular stimulation unit
  • a battery activated power pack with recharger
  • the Paratester, a unit for pretesting main system operation and electrode cables
  • surface applied skin electrodes
  • power and electrodes cables
  • a control and stability walker with finger activated control switches.

FNS is the use of low-voltage electricity to elicit a skeletal muscle response. The electrical excitability of the nerves and muscle tissue provides the basis for its therapeutic use. Normally, movement of the extremities originates in the motor areas of the brain.  For various reasons, such as trauma, stroke, neurological disease (e.g. multiple sclerosis), congenital deficiencies, or tumor, the neural pathway between the cerebral cortex and the muscles may be disrupted or damaged.

The basic premise of functional neuromuscular stimulation is that a viable muscle, even though atrophied, can still be activated and controlled by means of electrical stimulation applied below the level of injury.

In addition to eliciting contraction of skeletal muscles, electrical stimulation has also been employed in a variety of other applications, such as to contract the heart muscle (i.e., cardiac pacemakers), alleviate pain (TENS units), improve bladder control, control epileptic seizures, prevent the progress of scoliosis, promote bone strength, improve blood circulation in various parts of the body, control respiration, and stimulate the auditory nerve and visual cortex.

The Parastep I™ System stimulator generates sequences of electrical pulses. These pulses are passed to target peripheral nerves through surface applied skin electrodes, placed over selected muscles and sensory nerves of the lower extremities.  Stimulation of the quadriceps muscles causes a contraction which results in knee extension, enabling the user to stand. Stimulation of sensory nerves in the lower extremities initiates a reflex contraction to flex the hip, knee, and ankle, lifting the foot off the floor; quadriceps stimulation then cycles on, to extend the knee in preparation for taking a step. The user controls stimulation through a user-friendly keypad on the stimulator unit or via control switches mounted on the electronically modified walker.  The walker provides balance and stability to the user while standing and walking.

Candidates for The Parastep I™ System are spinal cord injured individuals for whom standing and gait training is indicated following evaluation by medical rehabilitation professionals.  The Parastep I™ System is a FNS modality provided as an alternative to traditional bracing and other orthotic approaches to long term rehabilitation management of spinal cord injury.

A complete evaluation of prospective candidates is conducted by a physician and physical therapist at Parastep I™ System program sites.

The clinical evaluation consists of an examination of the following:

  • musculoskeletal integrity
  • range of motion
  • muscle contractile response to electrical stimulation
  • cardiorespiratory capacities
  • spasticity
  • learning capability to operate the system
  • patient motivation
  • sensory tolerance of electrical stimulation required to contract muscles

Functionally, potential candidates must demonstrate the following:

  • sufficient muscular force with FNS at the hip and knee required for function
  • adequate cardiopulmonary reserve
  • the ability to transfer independently and safely lower him/her self to the ground without the system operating
  • adequate standing tolerance
  • balance and trunk control
  • hand/finger dexterity to manipulate system controls

Individuals with the following conditions should not be considered candidates for the Parastep:

  • cardiac demand pacemaker
  • cancer in the area of electrode placement
  • severe scoliosis
  • severe osteoporosis
  • skin disease at stimulation sites or over swollen, infected, or inflamedareas or skin eruptions, e.g. phlebitis, thrombophlebitis, varicose veins
  • irreversible contracture
  • autonomic dysreflexia

The obvious benefit derived from Parastep I™ System use is its potential to enable spinal cord injured individuals to attain limited ambulation.  The Parastep I™ System enables users to stand and walk short distances at home or in the work place without long leg braces.  The Parastep I™ System may assist users to perform some of the activities of daily living which require standing.

For example, some of the activities reported by users include simple tasks from emptying a dishwasher, drinking from a water fountain, operating a photocopier, filing, placing and removing books from a bookcase, obtaining a soft drink from a dispensing machine to going to a restaurant, preparing meals at home, entering and exiting narrow passageways, and making presentations, teaching a class or greeting customers while standing.

Every user will differ in the level of skill achieved with Parastep I™ System use.  Functional goals will be evaluated for each user by the physical therapist, and a training program will be developed to accomplish these goals.

It has long been accepted in rehabilitation medicine, that prolonged inactivity has extensive deleterious physiological consequences.  Few question the benefits of standing after spinal cord injury.  The use of functional electrical stimulation by individuals with neurological impairments has been shown to be therapeutically effective for retarding and reversing muscular atrophy; increasing local blood flow and circulation in stimulated muscles; and increasing the range of motion at inactive joints.

The Parastep I™ System affords the user the ability to activate his/her own muscles to stand and bear weight on the long bones of the legs, when and where the individual desires to do so, whether at home or in the work place.

The Parastep I™ System, when used in an approved program of long-term spinal cord injury management, will enable the individual to stand and walk short distances.  Users of the system report that Parastep I™ System also enhances emotional and psychological well-being by enhancing self-esteem and improving morale.

Physical therapy is a key component of the Parastep.  Thirty-two sessions of physical therapy, including instruction on system use and gait training, are provided to users when they purchase a system.  This training is provided by hospital-based physical therapists who have completed Sigmedics, Inc.'s clinical training program.

Though some facilities may offer an accelerated training program (the individual is seen daily, often once in the morning and then again in the afternoon), dependent on the participant's conditioning  and self-progress, typically, Parastep training is conducted a minimum of two to three times per week, on an outpatient basis.  Patient information, treatment records and functional measures are collected at each training session and consolidated into a progress report.

Each user's progress is carefully monitored with frequent adjustments made in the training program to accommodate each user's individual requirements.  Treatment sessions progress at a pace set by each user's ability, skill and proficiency.

Achievement levels in walking vary with the individual user's level of injury, learned skills, and physical condition.  Distance walked will vary and increase with practice and training.  Individual goals are established for each user by the physical therapist. Studies conducted in different clinical settings reported distances walked by individual users ranging from a few feet to over a mile at a time, with the average distance being around 1,450 feet (The Journal of Spinal Cord Medicine, Volume 19, Number 2).

Use of the Parastep I™ System is an energy consuming, cardiovascular workout that requires commitment by the user to achieve results.  Users have reported that energy expenditure during walks using functional neuromuscular stimulation is similar to the energy expenditure requirements while using long leg braces.

Energy expenditure, however, may decrease over time as the user's walking speed and proficiency with the system improves.  Users have experienced an increase in energy efficiency with increased system use.

Currently there is available a six (6) channel unit which stimulates the gluteal muscles, quadriceps and lower leg.  The six (6) channel unit provides support and trunk stability for patients.

The current price for a six (6) channel unit is $13,222.68.  The price does not include shipping, handling, insurance, nor the cost of physical therapy training and instruction in system use, which may fluctuate from center to center.

Our experience to date with insurers has been very positive.  Answers to questions regarding eligibility, coverage and reimbursement are dependent on the language and scope of the individual insurance policy.  Insurers traditionally base their reimbursement decisions on various factors, thus each case is usually judged on its own merits.  We are very pleased to announce that (effective April 1st., 2003) the Centers for Medicare and Medicaid Services (CMS) made a National Coverage Determination extending coverage to the Parastep I™ System for qualifying Medicare beneficiaries. Specific HCPCS codes have been assigned to cover costs associated with both the physical therapy training services (Code 97116) as well as for the acquisition of the Parastep I™ equipment (Code E0764). Please note that Medicare covers approximately 80% of equipment acquisition costs. Following the CMS example, other major insurers have either already amended (e.g. Aetna Insurance Company) their policies to cover our technology or are in the process of reviewing the same, hopefully reaching a similar decision. Sigmedics, Inc. has set up its own Patient Case Management Department precisely for the purpose of facilitating insurance reimbursement efforts by undertaking the preparation, collection, verification and submission of all pertinent documentation to insurers.  These efforts are closely coordinated with clinicians and Parastep I™ Program participants.

The Parastep I™ System is the first functional neuromuscular electrical stimulation device available for standing and walking short-distances with a walker, by appropriately selected and properly trained spinal cord injured individuals.  A variety of FNS-assisted exercise devices are sold commercially, but none of these enable standing and ambulation.  There are no other commercially available FNS systems for ambulation.  The Parastep I™ System is the only such device to have received U.S. Food & Drug Administration approval for marketing in the U.S.A. (FDA #P900038) following multi-center clinical trials geared towards demonstrating the device's safety, efficacy and clinical utility.

To acquire a system, an individual must participate in an approved Parastep I™ System clinical training program and obtain a physician's prescription.  For a listing of Parastep I™ System clinical programs, please select Clinics from the main menu or click here.   Sigmedics Case Management Department will gladly assist with insurance reimbursement related questions.

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