Pressure Mapping For Wheelchair Users


As a parent or caregiver of a child who utilizes a wheelchair, one understands the constant struggle of incorporating
comfort, function and safety within a child’s seating system. The threat of skin breakdown or pressure related wounds is real and can create a life-threatening concern if not properly addressed. Today, within the United States, we are seeing more wheelchair users than ever before. Recent estimates suggest at least 1 in 250 people currently requires use of a wheelchair, on at least a part-time basis (Furumasu, 2007). The wheelchair industry has experienced unprecedented growth in the last decade, including the development of state-of-the art equipment and accessories to provide the user with never before seen comfort and function.

Unfortunately, using a wheelchair comes with inherent risks, at the forefront of which is skin breakdown. The populations most at risk are the elderly and individuals who have experienced spinal cord injury, although recently, there has been a notable increase in pressure related wounds within our pediatric wheelchair user populations. These populations present with a pressure wound incidence rate of 23 percent and 60 percent respectively (Univ of Washington, 2004).

Therapists, equipment providers and end users alike have long known about the benefits of incorporating a pressure mapping analysis into the wheelchair seating assessment, intervention and daily follow-up, but until recently, pressure mapping systems have been too costly for many facilities, clinics, caregivers or end users to implement. Thanks in part to new software and a new manufacturer on the playing field, pressure mapping has suddenly become an option for virtually any facility’s budget.


A pressure mapping system is a combination of a hardware mat and computer software which work together to produce a visual image of the user’s contact area. This color-keyed image somewhat resembles doppler radar, similar to what one may see on the nightly weather broadcast (i.e. red equals strong storm and green equals a gentle rain). The thin pressure mat will be placed on top of the user’s seating surface, between the surface and the client, and each sensor within the mat will simultaneously take three pressure readings per second, producing an average of the readings and displaying the mean reading in millimeters of mercury (mmHg) on the software image display, which will correlate with a color based on the intensity of the pressure being exhibited.

Experts have often debated about the exact pressure readings which are deemed acceptable when pressure mapping the client, and further research is needed to reinforce the current theories. In general, most researchers agree that setting a goal of keeping the peak pressures under the client at or below 80 mmHg , in conjunction with ensuring the wheelchair user is performing adequate pressure shifts, as often as every eight minutes, will often ensure victory in pressure wound prevention. With any type of seating system intervention, it is important to remember, as a clinician, we cannot remove pressure from an individual, as the amount of gravitational force pushing the client into the seat, as well as the amount of mass contained within the client will remain relatively consistent, but we can and must redistribute that pressure to be successful.



A myriad of benefits are associated with pressure mapping, the most common of which is pressure assessment. Through the use of these systems, the therapist, equipment provider or wheelchair end user can see, almost instantaneously, the amount of pressure which exists under the user. Mapping can often detect asymmetries, such as pelvic obliquities or rotation, or peak pressure concerns over bony prominences, which are often undetectable by the naked eye. By simply sitting on the mat, the evaluator has a much clearer picture of problem areas or adjustments which may be necessary to ensure adequate pressure distribution and an improved client-equipment fit. This information can be used to assess a user’s current seating situation, enhance a letter of medical necessity with images, or develop creative solutions to difficult seating presentations by gaining immediate feedback on the interventions which are being implemented.

Many clinicians are aware of the aforementioned benefits pressure mapping beholds, but many are not familiar with some outside-of-the-box applications which can also serve to be very useful in clinic. End users and clinicians alike find pressure mapping to be extremely useful in conjunction with air cushions to assess a user’s daily proper inflation. By initially overinflating the air cushion, the client will present with poor pressure distribution, as evidenced by the high pressure readings on the software. As the user or clinician opens the external air valve on the air cushion (if it is a single valve option), the client will sink into the air cells, resulting in improved pressure readings on the mapping display. After the prime inflation levels are reached, the pressure mapping software will show increasingly poor pressure distribution. Through the use of this simple and quick application of pressure mapping, an everyday wheelchair user can routinely check and ensure the air cushion inflation is ideal, and significantly reduce the risk of increased pressures under the contact area.

Therapists routinely work with clients who present with cerebral palsy or other diagnoses which result in a significant loss of sitting balance or righting capabilities. Therapists can easily incorporate pressure mapping into routine neuro-reeducation treatment, and make treatment fun by turning on the center of gravity option on the mapping system and have the client sit on the edge of a mat or a firm surface, with the display in front of them as a mirror image. Assist the client into reaching a neutral position and stick a small sticker on the center of gravity indicator on the display screen while the patient remains stabilized in a neutral sitting position. Allow the patient to return to the baseline, asymmetrical position, and encourage the client to pull into neutral and attempt to line up the center of gravity marker on the display with the sticker on the screen, thus encouraging an ideal neutral position. This center of gravity option can also aid in the assessment of drive wheel placement, frame width, seat to floor height and selfpropulsion efficiency.


For years, the longstanding disadvantage associated with pressure mapping has easily been the price. With the base price for the majority of pressure mapping systems starting at approximately $7,600 and easily reaching into the $12,000 range for wireless systems and advanced software, thousands of clinics, facilities and end users could not afford to put this valuable tool to use. The multitude of benefits noted above has long been unattainable for thousands due to the prohibitive cost of such systems.


Precision Seating Solutions L.L.C, a new company based out of New Jersey, is revolutionizing the pressure mapping industry with their creation of the PS 256, an affordable pressure mapping system. The PS 256 contains every clinical feature, application and benefit as the high cost systems, but retails for under $3500.

Steve Guarino, President and CEO of Precision Seating Solutions L.L.C. reports he frequently gets asked how a pressure mapping system with all of the same qualities can be produced at such a reduced cost. Steve explained, “It’s simple, really. The wheelchair industry has become accustomed to using pressure mapping systems, which were really, originally designed for intricate and detailed research in the automotive, aeronautic and veterinary fields. As a therapist, one does not need to know the raw data of a specific cell or the pressure exerted by an area the size of a pencil eraser under the client. We have redesigned and reinvented the traditional pressure mapping system to incorporate all of the clinical features every therapist needs, with a reduced amount of sensors, 256 to be exact, and
streamlined the software into an easy to use, straightforward format, which assimilates quite well to the letter of medical necessity required my most third party payers and funding sources.”


Over 450,000 pressure related wounds are reported annually amongst wheelchair users and hospitalized patients. When one considers the average cost of hospitalization due to a pressure related wound or ulcer is $37,800 (Lyder & Ayello, 2008), the implementation of a pressure mapping system and the multitude of advantages that come with it in regards to treatment, assessment and client education are more than worth the capital expenditure, especially
in light of the fact that new technologies, and companies, have opened the door for smaller facilities, individual end
users and the cost conscious consumer.

Simply stated, from a pediatric perspective, if a pressure mapping system can prevent the appearance of pressure related wounds and keep our children in a safe, comfortable and functional position within the wheelchair, the pressure mapping system has paid for itself and has saved. It would help save facility dollars, increase client’s comfort and wheelchair tolerance, and promote a better quality of life for individuals in wheelchairs.•

For more information on Precision Seating Solutions L.L.C visit

Leave a Reply