While every effort has been made to ensure all information in this article is accurate, it is for educational purposes and shouldn’t be used as an alternative to professional care.  Appropriate professional advice should be considered before using any techniques or equipment discussed in this article.

Butt Boot Camp: A WheelchairJunkie’s Guide to Wheelchair Seating

Wouldn’t it be great if wheelchair seating was like a LazyBoy recliner:  Just plop yourself in, and you’re so comfortable you can’t keep your eyes open.  Unfortunately, wheelchairs aren’t that intrinsically comfortable.  However, through an understanding of basic seating components, you can come darn close to a LazyBoy (heck, with the right setup and a couple of beers, you may not recognize the difference!). Basic Seating Variables Seat Width  (illustration measurement #3) Unlike certain parts of the human anatomy, bigger isn’t better when it comes to seat width.  Your seat should be as narrow as possible without your hips contacting the sides of the chair.  (To measure the width of your hips, place a book at each hip and measure the distance across the inside width -- Top End taught me that trick fifteen years ago.)   Too wide of seat encourages poor posture, causing you to lean to one side, and allows your hips to shift. Seat width also affect the chair’s performance, as on many chairs the seat width determines the overall width of the chair (for example, a  Bounder powerchair with a 16” seat width is 2” narrower than the same chair with an 18” seat width).  A chair that is a fraction of an inch too wide can mean inaccessibility to a vital place like the bathroom.  Many high production powerchairs -- as with Jazzy and Permobil -- use a one-size-fits-all base, so the seat width may not affect the overall width of the chair; still, for proper posture, choose the correct seat width.  I know, you like an extra inch or two to tuck in your winter parka; but, remember that extra seat width probably isn’t in your chair or body’s best interest. Seat Depth (illustration measurement #1) It’s tricky to find the correct seat depth.  If the seat is too deep, it encourages your hips to pull forward in the seat, causing you to slouch, rotating your pelvis and rounding your spine.  On the other hand, too shallow of seat depth causes the underside of your upper legs to extend beyond the edge of the seat, placing more pressure on your sitting (ischial) bones.  Additionally, because too little seat depth doesn’t provide enough support, you experience less stability, fatiguing muscles and tendons, and have less control of your chair.  Similar to seat width, seat depth also affects a chair’s performance.  On a manual chair, added seat depth will make the chair less agile, placing more weight ahead of the drive wheels.  On a conventional powerchair, greater seat depth may increase the overall length of the chair.  And on a powerbase, increasing seat length may change the center of gravity -- including increasing the rocking motion of mid-wheel drives -- and affect overall length.  While seat depth is usually a fixed element at the time of construction, it can be affected by the type of backrest used.  A sling backrest may have adjustable tension, which allows you to sit farther back in the seat, or a solid backrest may allow you to sit farther forward.  Therapists have their wiz-bang formulas and cute miniature tape measures, but the best way to determine what’s most comfortable for you is by paying attention over the long haul to what feels best. Seat Angle Seat angle, commonly called “squeeze” (or “dump” by the uncouth), is when the seat has a permanent slopes from high in the front to low in the back (not to be confused with tilt seating).  Most manual and powerchairs come with built-in seat angle adjustment mechanisms, which allows for your customization.  Seat angle helps keep your weight in place, preventing you from sliding forward -- security and stability that many users need.  The disadvantage is that seat angle increases shear forces (the tension on your skin as your body tries to slide forward in the seat), and too much angle can cause problems with disks, curvature of the spine, and sacral pressure sores (doesn’t that sound like fun?).  So, the moral of the story is, some angle may benefit you, but too much may be dangerous.

Backrests (illustration measurement #2) Back in the hippie days of free pot, the only backrest choice we had was sling upholstery, which didn’t provide lumbar support or postural stability.  Fortunately, now you can have a molded, rigid backrest with lumbar support on almost any chair.  Formed backrests discourage the advancement of a kyphosis, reduce back pain, and provide a more comfortable and functional posture.  Adjustable angle, depth, and height improves your visual field, fostering effective environmental control. The backs (popularized by Jay) range from low-profile, lightweight sportschair models to deep profile powerchair models that provide extensive lateral side support. Price range: $70-$600.

Seat Cushions The right cushion can provide comfort, positioning, and prevent pressure sores, but need not meet that criteria for every user.  An ambulatory person who only uses a wheelchair to go shopping doesn’t have the same needs as a high-level quad who spends eighteen hours per day in a powerchair, so it’s important to fully understand your requirements and select the appropriate cushion, weighing the pros and cons of the different cushion styles.

Foam The least expensive material for a cushion is foam.  Today, foam comes in a wide array of densities and can be shaped to conform to the user.  Top-the-line foam cushions are molded in place by therapists, custom fit to your rear, and can be the ultimate in pressure sore prevention.  At the other end of the spectrum, an inexpensive, flat foam cushion off the shelf may be all that you need, saving you hundreds of dollars over an advanced air or gel cushions.  The advantages of foam are that it’s lightweight, gives you seating stability, and doesn’t deflate or leak.  Foam does, however, wear and compress, so it takes careful monitoring of its condition and requires timely replacement.  Price range:  $40-$150 for off-the-shelf; $400+  for custom molds.

Air Air flotation cushions work by supporting you on a bladder of air.  The concept is that pressure distributes evenly, avoiding single pressure points on your skin..  By all accounts, air cushions like ROHO work extremely well at avoiding pressure sores.  Of course air flotation is not without drawbacks, as it’s hard to achieve the proper air pressure -- not too much or too little -- and it must be regularly inflated to maintain pressure. What’s more, if you travel in elevation, the cushion’s pressure changes, which affects performance and comfort.  Oh, yes, and there’s one other small problem: Air flotation cushions puncture, leaving you without any protection!  Although most air cushions are made with very heavy rubber, they do get leaks. Price range:  $150-$450.

Gel Gel cushions are filled with several pockets of gel, usually featuring a foam base for positioning.  The gel is intended to replicate the consistency of body tissue, in effect, giving more cushion to your rear.  Gel cushions work well when functioning correctly, but have many drawbacks.  First, they’re heaving, adding as much as a fourth of the weight to a lightweight sportschair.  Secondly, gel cushions “bottom out,” meaning that the gel may spread out toward your hips, allowing the highest pressure points of your rear to go unprotected from the hard base.  Lastly, like air cushions, gel cushions are prone to leaking, especially at seams, and are difficult to patch at best.  Price range:  $150-$450.

Honeycomb Thermoplastic urethane cushions -- that’s “honeycomb” to you and me -- are comprised like a beehive, with many open cells.  The cells allow air to travel throughout the structure, creating the cushioning effect. Honeycomb cushions are lightweight, machine washable, and puncture-proof.  Still, many users find them too firm.  (I used a Supracor honeycomb cushion for several months, and while it was great at first, over six months time it became compressed and gave me pressure problems.)  Honeycomb cushions remain in the first generation, so time has yet to tell of their true applicability.  Price range: $175-$400.

Captain’s Chair Seating The trend in powerchairs these days is captain’s chair seating.  A top-of-the-line captain’s chair -- like Recaro or Permobil Corpus -- provides the ultimate seating system in one package.  The Recaro offers adjustments for almost every dimension, including lumbar, seat depth, back angle, and seat angle.  Be forewarned, however, not all captain’s chairs are created equal.  The systems built by QUICKIE, Invacare, Jazzy, and E&J are nowhere near the quality of Recaro and Permobil products, and may not be suitable for users with a high risk of pressure sores (additional cushions do not work on most captain’s chairs). Conclusion Indeed, judging by the wide range of seating options, there’s no single correct seating system. There is, however, a single correct seating system for you.  By proper fitting and weighing the pros and cons of the different products on the market before you invest in a system, you can achieve maximum comfort and safety in your chair, enabling you to live life to the fullest.

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