Customization is key to unlocking maximized function for each wheelchair user’s unique needs.

 Providing an optimum seating solution to a mobility user evokes a bit of the Goldilocks principle, which connotes the best way to find a solution that is “just right” is to look within specific margins rather than at the extremes. While the very wide range of options for seating materials and accessories is meant to offer performance and versatility, the sheer numbers of options can heighten the complexity of determining which solution best serves the user. To solve this problem, a multidisciplinary team of therapists, suppliers, physicians, caregivers, and the mobility device user can work together to find the solution that fits just right. This article explores how to make that fit by spotlighting the latest seating options and how they can be applied for optimum user satisfaction.

Putting the Puzzle Pieces Together for an Optimum Outcome

Typically, the mobility device user sees a physician for referral to a wheelchair evaluation. The device user, family members, seating therapist, and supplier then meet for 1 to 4 hours to assess the user’s seating, positioning, and mobility needs. There are many factors to consider. For example, what makes and models of wheelchairs have been tried in the past? What has worked and what has not? What are the current health concerns, including past medical history, progressive nature of the disease process, recent or upcoming surgeries, postural deterioration from the last seating evaluation, and history of wounds? Other considerations include the patient’s lifestyle. Is the individual active or sedentary? Is the patient working, going to school, taking care of small children, or perhaps driving a vehicle? If so, is he or she driving from the chair or transferring into the car and then loading the chair? If not driving, is the mobility device user transported in the wheelchair or transferring into the standard car or van seat? What sort of terrain needs to be traversed? How are transfers typically performed? Are there muscle imbalances, range of motion limitations, or postural asymmetries to consider? How well does the mobility device user perform pressure relief independently? All of the answers to these questions must be mindfully considered when recommendations are made. When all of the puzzle pieces are snapped together, the outcome allows the end user to experience safety, function, and comfort while using the chair for all daily activities.

Using Technology to Bolster Medical Justification

Under the current insurance system, it is important to provide subjective data for medical justification. Some of the most subjective information comes in the form of technology advances. Determining the appropriate rehab style seating system is imperative to success with any wheelchair. There are two theories about safe seating: loading and off-loading. Determining loaded areas is most often done with a pressure mapping system. This is performed for seating considerations, both on the cushion and on the backrest. Consumers can be mapped using a sensor system that will give the seating specialist information regarding peak pressures, areas of risk, and surface area distribution measured in mm Hg. Cushions or backrests can be compared in side-to-side images to show similarities and differences. A prominent part of the seating evaluation is education, and the pressure mapping system is an excellent tool for this purpose. The seating therapist should have the client perform a pressure relief in their typical manner while the mapping system runs in real time. The client can watch the mapping system screen during the pressure relief, or it can be played back for them. This will indicate to the therapist and to the client how effective the pressure relief is and whether the areas of concern and the seated surface are clearing. This is a very accurate indicator for most cushions. Allowing the client to sit on the sensor pad and cushion for up to 15 minutes is important to get an accurate reading, as body heat and settling can change the distribution of the elements (gel, air, foam) in the cushion. A specific instance where pressure mapping is not an accurate depiction of what may be happening on the seated surface is with custom molded cushions that are built to off-load bony prominences. This style of cushion and backrest uses a 6- to 8-point pressure distribution model over soft tissue areas to provide positioning and support and protect skin integrity. Mapping on this style of cushion will cause a slinging or hammock effect and will not allow for accurate pressure readings. In this instance, gauges are used in the wells to determine appropriate fit of the custom mold effectively off-loading trochanters, ischial tuberosities, and coccyx.

Additional Seating Considerations

Other seating considerations include appropriate headrests, armrests, tricep blocks, trunk supports, pelvic positioning, lower extremity supports, and legrests. Headrests are offered in a variety of styles and sizes. They are typically used on power and manual tilt in space chairs to support the head in the tilted and/or reclined positions. They are also mandatory if the client is transported in the wheelchair. Other modifications and additions to headrests can include lateral support in the form of a tri-wing, posterior support in the form of an occipital cradle, and lateral anterior support in the form of lateral facial pads. Removable headrest hardware is imperative if the client is transferred via a dependent patient lift system.

Armrest styles vary widely for power chairs depending on the amount of support needed by the client. On power wheelchairs and manual tilt in space wheelchairs, high amounts of support are provided via large padded arm troughs with padded Velcro straps and range down to a standard armrest with gel or foam. On the ultra-lightweight chairs, the most traditional style of armrest would be the tubular swing-away arm, but the single post mounted armrests are also available on many models. Armrest height is crucial in supporting shoulders and preventing shoulder subluxation as well as allowing for safe propulsion and pressure relief. Height-adjustable armrests provide for a variety of positions and assist the supplier and therapist in creating the most appropriate fit for the client. Tricep blocks provide posterior support for wheelchair users who lack the upper extremity innervations to maintain arm position on the armrest, most often during tilt.

Trunk supports are available in several varieties. When attempting to achieve a lateral stability, a deep contour, custom molded backrest, or swing-away lateral supports, would be appropriate. When determining the type of lateral trunk support, keeping in mind the type of transfer that the patient performs is important. If a patient is independent with a slide board transfer but is unable to independently swing away a lateral support, this style needs to be rethought. Clients also may require some form of anterior trunk support, most often when transporting in their wheelchairs in a vehicle. A chest strap, vest, or harness style can be used. These typically utilize Velcro or buckles to maintain the position. They come in a variety of sizes and are male and female specific.

Pelvic positioning is a cornerstone for wheelchair seating and positioning. There are several varieties of pelvic positioning belts that come in an array of widths, padding types, and buckle styles. More important than the materials, however, is the positioning and attachment placement of these items. If the belt is mounted too far posterior, it no longer will provide pelvic support and will pull over the abdomen. Trialing positioning of the belt with a 90-degree, 60-degree, or 45-degree pull will give the therapist a much better idea of the most appropriate position for the client in order to help control pelvic position and asymmetries.

Footplates and legrests also come in a variety of options including swing-away and center mount styles for power chairs and fixed and swing-away on ultra-lightweight chairs and manual chairs. Footplates have the option of being angle adjustable, flip up, interlocking, or extralong. Legrests can be fixed at an angle on the chair or can be elevated using electronics or manually. Lower extremity supports are important for safety considerations, and options include heel loops, ankle huggers, calf pads, calf straps, hip guides, hip pads to contain hip abduction, and pommels to minimize hip adduction.

Cushion materials, as well, can be considered among the landscape of seating options. Many of today’s cushions are manufactured from one of several different types of materials, including foam, gels, air, and combined mediums. Generally, foam cushions require little maintenance, and newer foams are designed to have breathable properties. Polymer gels are engineered to reduce shear, and are sometimes used with a foam-based cushion. Fluid gels, too, can reduce shear and allow movement of bony prominences. Air cushions can minimize the buildup of moisture and heat, and are designed to be lightweight. Another option among cushions are those that combine materials such as foam and air to provide users the benefits of each.

Mapped for Success

When all of these parts and pieces are taken into consideration and arranged appropriately, the client will present with general seating principles of safety, function, and comfort. Often, during the evaluation process, a person is pressure mapped on a multitude of cushions to determine the safest, most effective cushion for them. It is imperative that they also be mapped on the cushion when the final product is delivered. This step is often missed and can have detrimental results. In the world of wheelchairs, a quarter of an inch can be the difference between a pressure sore or back pain, or inefficient propulsion. If the patient was mapped on a gel cushion during the seating evaluation and it mapped quite well, it cannot be assumed that it will map exactly the same upon receipt of the new chair. It is likely that adjustments to legrest length, armrest height, lateral trunk support, and seat depth could be made to a chair to allow for safe and effective mapping of this cushion. The process of wheelchair prescription can seem tedious to clients at times. The extensive history review, mat evaluation, product discussion, and measurements take time. The medical justification for each and every part of a chair is labor intensive and requires precision. All of these pieces allow for the client to have the most appropriate chair to use for daily life. Wheelchairs are just as unique as the individuals who use them, and customization is the key to unlock the highest function possible. RM


Katherine M. Collins, PT, DPT, ATP, is the Seating and Positioning Specialist at Madonna Rehabilitation Hospital. Collins earned her DPT in 2006 from the University of Nebraska Medical Center. She started at Madonna in January 2012 following 4 years at Children’s Hospital and Medical Center and 2 years with Quality Living Inc, practicing school-based therapy. Collins specializes in seating and positioning and mobility, including manual and power chairs, pressure mapping, power assist mobility, and custom seating. She sees patients of all ages with a wide range of diagnoses including spinal cord injury, traumatic brain injury, CVA, neurologic impairments, trauma, and orthopedic impairments. For more information, contact [email protected].