A Primary Care Provider’s Guide to Wheelchair Prescription for Persons With Spinal Cord Injury

A 23-year-old female with T10, motor incomplete paraplegia presented with low back and buttock pain 7 years after initial injury. She rated the pain at 8/10 to 10/10 at its worst and reported that it significantly interfered with her sleep and quality of life. Her primary care physician (PCP) diagnosed her with sacroiliac joint dysfunction. She had minimal relief with oxycodone and sacroiliac corticosteroid joint injections.

Unrelated to her pain, the patient was referred to a seating clinic for a new manual wheelchair. During the interview, she reported that her back/buttock pain significantly improved when sitting in the driver’s seat (a bucket-style seat) of her car. A special wheelchair frame, similar to a bucket seat, was trialed, and she reported an instant decrease in her pain from 5/10 to 2/10. The seating clinic determined that her wheelchair was contributing to her chronic pain by creating squeeze on her hips.

This case is an example of an individual with spinal cord injury (SCI) presenting to a PCP with medical complaints secondary to suboptimal wheelchair fit. The PCP plays a key role in wheelchair prescription, evaluation, and adjustments and should be aware of both the process of wheelchair acquisition and indications for reevaluations and modification.

Critical to prescribing a wheelchair optimized to the patient’s needs and abilities is collaboration with an occupational or physical therapist who specializes in wheelchair seating. Such therapists typically spend at least one day a week performing wheelchair evaluations, fittings, and training. Some of these specialized therapists have the Rehabilitation Engineering Society of America (RESNA) seating and mobility specialist SMS certification. SMS-certified therapists can be identified by searching RESNA’s certified professional directory. (https://www.resna.org/member-directory/individual). The SMS certification is often referred to as ATP/SMS. Persons with the SMS certification will always have an ATP certification (assistive technology professional) because it is a prerequisite for sitting for the SMS exam. ATP/SMS-certified therapists will have provided at least 1,000 hours of seating- and mobility-related service directly to consumers (over any time period) and have passed the ATP exam before being eligible to sit for the SMS exam. To be eligible to take the ATP exam, therapists must have provided at least 1,000 hours of assistive technology–related services (in a 6-year period) directly to consumers.

If a search reveals no local SMS-certified therapists, the PCP can contact several SMS therapists in the region and get their recommendations for a local specialist. Throughout this article, we refer to therapists serving this role as “seating specialist.” It is imperative that PCPs insist on the participation of an experienced seating specialist in wheelchair prescription and adjustment because payers will not approve another wheelchair just because the first was incorrectly configured. Per payer stipulations, a new wheelchair system can only be obtained, at minimum, every 5 years. The only justifiable reasons to obtain a new wheelchair prior to the 5 years are a new qualifying diagnosis (ie, the client has paraplegia and is then diagnosed with multiple sclerosis) or weight gain or loss that cannot be accommodated by the current equipment. Progression of the current diagnosis is not sufficient. Even after the 5-year mark, thorough documentation must be provided to prove replacement is necessary. The involvement of a seating specialist strongly influences the success or failure of a new wheelchair system.

Wheelchair prescription and acquisition generally follows the sequence outlined in Figure 1. The physician’s main role is to thoroughly document the medical condition that necessitates a new wheelchair.¹  Medicare (and many other insurers) requires a “face-to-face encounter” within 45 days of power²  and 6 months of manual³  wheelchair prescription. This face-to-face encounter involves evaluations performed by the PCP and seating specialist. The PCP’s evaluation should document mobility limitations, how the patient’s medical condition affects activities of daily living (ADLs), mobility-related ADLs, the patient’s home setting (including whether the entry/exit is wheelchair accessible), and the wheelchair user’s ability to operate the prescribed device. If the patient can ambulate, symptoms and limiting diagnosis should be documented. The encounter should also document the patient’s current height, weight, and cardiopulmonary, neurologic, and musculoskeletal examinations.^2,3  See the box, “Medical Evaluation Guidance to Avoid Funding Denials” for documentation tips to avoid insurance denials.

The evaluation performed by the seating specialist supports the necessity of specific wheelchair equipment as it relates to mobility-related ADLs. This includes subjective and objective data regarding the patient’s impairments, functional level, current equipment, activity, and participation. Coordination with the seating specialist is critical, as denials occur when the medical and seating evaluations are discordant.^4,5 

The PCP and seating specialist collaboratively write a wheelchair prescription after the face-to-face encounter. This prescription includes wheelchair type, initial date and duration of need, specific components (eg, cushion, backrest, power seat functions), and medical justification. The PCP’s medical justification must document the face-to-face encounter, mobility limitations that cannot be resolved with other mobility aids (eg, cane or walker), where the wheelchair will be used, and that home mobility will be improved. The seating specialist provides specification of and justification for medical necessity for components including arms/foot/leg rests, rear wheels, cushions, and seat frame modifications.

A wheelchair prescription has two core components: a wheelchair base (manual or power) and the seating interface (seating cushion and backrest).⁶  The physician may assume a power base is needed for persons with cervical SCI and a manual base for persons with thoracolumbar SCI. However, wheelchair base selection should be based on the patient’s individual medical needs, physical abilities, preferences, home and community physical environment, and availability of accessible transportation.

Wheelchair bases and the accompanying components that support optimal health and mobility in persons with SCI are complex rehab technology (CRT) products. CRT products are individually configured devices designed to meet an individual’s unique medical, physical, and functional needs in the context of a medical condition.⁶  PCPs should aim for the highest justifiable wheelchair and accessories for patients with SCI to ensure functional and medical goals are achieved. An experienced seating specialist will be equipped to help select the highest justifiable wheelchair base and components for the individual.

Manual wheelchairs are classified into classes primarily by frame weight³  (ie, no wheels or leg rest) and rear axle adjustability. The two classes most commonly prescribed for this population are K0004 (high strength lightweight) and K0005 (ultra-lightweight). Custom fit of the lightest possible chair is recommended by clinical practice guidelines⁷  to delay the onset and progression of the shoulder and wrist pain and pathology that is highly prevalent in this population. The clinical practice guidelines recommendations can only be achieved with a K0005, thus PCPs should aim for a K0005 to optimize outcomes.

PCPs may be pressured to prescribe K0004 manual wheelchairs for persons with SCI because they are less expensive for the insurer. K0004 chairs do not have fully adjustable rear axles and are not the lightest available. Clinical practice guidelines⁷  recommend that the rear wheel be as far forward as possible without loss of stability and that the wheel be positioned so the user’s elbow is flexed 100°–120° when the hand is at top, dead center of the rim (full extension = 180°). Achieving this rear wheel position is based on the individual. K0005 chairs allow both vertical and horizontal adjustment of the rear axle to fully customize rear wheel position for the user. K0005 chairs also allow the addition of camber, which tips the rear wheel inward at the top and improves the user’s shoulder alignment during propulsion. Camber is not available on K0004 chairs. Therefore, PCPs should resist pressure to prescribe a K0004.

Power wheelchairs are classified into groups based on performance requirements (Table 1),²  with higher performance indicated by higher group number. There are additional, critical differences that impact patient health and mobility, including availability of drive wheel vibration dampening and supporting multiple power seat functions. The most common groups prescribed for this population are Groups 2, 3, and 4.

PCPs may be pressured to prescribe Group 2 power chairs for persons with SCI because Group 2 wheelchairs are less expensive for the insurer and they can accommodate a subset of the features often required by persons with SCI. However, Group 2 chairs do not support drive wheel suspension and generally do not support more than one power seat function. These features are important health and mobility facilitators. Suspension dampens vibration, and cumulative exposure to whole-body vibration is associated with increased risk of muscle fatigue, nerve damage, low back, and neck and shoulder pain^8,9  and may increase the incidence of peripheral and cardiovascular disease and certain cancers.⁹  In addition, available evidence supports superior outcomes for edema,¹⁰  pressure relief,10 and pain¹¹  when multiple power seat functions are used synergistically (ie, tilt, recline, and lower extremity elevation). Thus, full-time wheelchair users with the above concerns should be prescribed Group 3 or 4 chairs to enable optimal prevention and management of health conditions. Table 2 matches health conditions with the power seat functions that can be used to manage them.

Since documentation must rule out lower forms of assistive technology in order to secure more complex technology, PCPs should begin with the premise that a manual wheelchair is appropriate and systematically evaluate the patient’s motor function, strength, ability/difficulty performing pressure relief, ADLs, instrumental ADLs, transfers, and self-propulsion around the home. Barriers/supports to home entry/exit should be noted (ie, ramps or steps, steepness of ramps) as should the primary mode of community transport/mobility (ie, owns modified vehicle, does/not drive from wheelchair, relies on paratransit or standard community transportation). Although medical necessity is based on “in-home use,” justification for higher level wheelchair bases requires evidence that the user is an “active” user, which requires out of the home use. Pain during any of these activities and or difficulty/inability to perform these activities in/from/with a manual wheelchair can indicate a manual wheelchair is inappropriately fitted to the patient.

Power assist wheelchairs (PAWs) are manual wheelchairs with motors that supplement the user’s push. These motors are either embedded in the rear wheels or are attached to the rear axle via a quick-release module. They are appropriate when an individual cannot functionally propel a manual wheelchair but requires a manual wheelchair’s compactness, maneuverability, and portability. These individuals must be able to adequately perform pressure relief maneuvers as PAWs cannot be fitted with power seat functions. Power wheelchairs are appropriate when individuals cannot adequately self-propel or perform pressure relief maneuvers. They are also appropriate if an individual can self-propel but requires power seat functions to manage pain, spasticity, edema, pressure relief, or other health or mobility concerns. Table 3 provides guidance on indicators for power assist and power wheelchairs.

At minimum, a seating system includes a backrest and cushion, with complexity increasing with ascending injury level and with increasing prevalence and severity of range of motion restrictions, deformities, and muscle tone. Although they are independent components, the backrest and cushion work in conjunction with the angle of the seat frame and angle of the backrest posts to achieve an optimal seating position.

An optimally selected and fitted backrest is comfortable, provides support to maintain body segment positioning, and minimizes trunk movement and energy loss during dynamic use of the arms. On manual wheelchairs, the default backrest is nonadjustable sling upholstery, which stretches over time, promotes kyphotic deformity and posterior pelvic tilt, and may reduce propulsion efficiency.^12,13  Independent of backrest material, backrests that are high may impair manual wheelchair propulsion by blocking scapular movement.¹⁴  Adjustable backrests that can be contoured to accommodate the user’s anthropometric, functional, and medical needs are preferred. Many of these backrests have a hard shell, foam padding, and adjustable mounting hardware. Backrest fitting can include, but is not limited to, moving the mounts up/down on the backrest posts, using the hardware to adjust anterior/posterior position relative to backrest posts and backrest anterior-posterior tilt, adding foam to support natural/pathological curvatures, and/or adding lateral supports. Manufacturers have developed a variety of approaches to provide support and adjustability. An experienced seating specialist and supplier can help the patient and PCP navigate the options.

As with wheelchair base selection, functional and medical needs should drive cushion selection. User response to cushions is highly variable,^15,16  necessitating individual assessment, cushion trials, and referral to a seating specialist. Cushion properties that must be considered during the selection process include pressure distribution, corrective or accommodative postural support, maintenance, weight, durability, air flow, and temperature regulation.¹²  Cushion materials and configurations are diverse, and the seating specialist and supplier can help navigate the options.

For many individuals with SCI, their PCP handles the majority of their medical concerns, including supporting acquisition of a wheelchair or renewing their wheelchair prescription. In every encounter with patients with SCI, and especially at every general medical evaluation, the PCP should evaluate functional status, mobility, pain, skin, and overall health. Changes in any system should prompt consideration as to whether the individual’s wheelchair could be contributing to the concern.

Good wheelchair fit promotes mobility and overall health in SCI patients.¹⁷  As illustrated by the case example, wheelchair fit should be included in the differential for acute (episodic care) and chronic (health maintenance) health concerns. It is important that PCPs are aware of indications that a patient may need a new wheelchair or seating adjustments. One common reason for referral for a new wheelchair or seating adjustments is improper alignment and posture leading to postural deformities, pain, or skin breakdown.^1,17  For example, shoulder pain may indicate strain from improper positioning in a manual wheelchair or excessive overhead reach in a wheelchair that is too low to the ground. There are many other issues that could indicate need for wheelchair adjustment or replacement. The Health Maintenance Checklist and Episodic Care Considerations at the beginning of this article serve as a quick reminder of systems and health concerns that can be impacted by wheelchair fit.

The PCP plays an essential role in wheelchair prescription and evaluation for individuals with SCI. Collaboration with an experienced, seating specialist is key to securing insurer approval and achieving optimal outcomes for the patient. A wheelchair prescription includes extensive documentation of the patient’s abilities and health needs and rationale for each part of the wheelchair selected. Wheelchairs and their components exist along a spectrum from standardized and nonadjustable to ultra-individualized and customizable. Optimized health and function often require higher end, more complex chairs. PCPs may experience pressure to prescribe and accept more basic, less customizable chairs and accessories, as these are generally less expensive. PCPs are advised to include wheelchair fit in the differential for all acute and chronic health concerns.

Awareness of indications for a new wheelchair or seating adjustments is important for health, function, and mobility outcomes in patients with SCI. When a new wheelchair or adjustments are indicated, PCPs should refer their patient to an occupational or physical therapist who specializes in wheelchair prescription and fitting, preferably within a wheelchair seating clinic system. An experienced, seating specialist will know how to best justify the custom configuration that will optimize a patient’s health.

The authors declare no conflicts of interest.