Published 8/04, Copyright 2004, WheelchairJunkie.com
Get a Grip:|
A WheelchairJunkie's Guide to Alternative Handrims
By Mark E. Smith
Few aspects marry us to our manual wheelchairs more than the handrims. After all, if you wish to
move the chair a foot or a mile, the handrims are the needed point of contact. For those with ideal
dexterity, powder-coated, anodized, or chrome handrims don't dictate a second thought - push and go.
But, what if you don't have ideal dexterity? This is where alternative handrim surfaces come into play.|
Vinyl / Plastic Coated Handrims
Vinyl-coated handrims (called "plastic-coated" by some funding sources and manufacturers), are aluminum
handrims dipped in a vinyl solution - resulting in a tacky, rubbery coating, similar to that on the handles
of some tools. For users with limited grip, the tacky surface of the vinyl allows a bit more hand adhesion,
so one can push with minimal grip. Additionally, the vinyl coating increases the diameter of the handrim,
adding surface for gripping or palming. |
Previous generations of vinyl-coated handrims were known
to chip, leaving divots with sharp edges. However, nowadays, most manufactures use more pliable materials
- almost closer to self-skinning foam than plastic - all but eliminating chipping, and softening damaged
edges. Beyond increased durability, vinyl-coated handrims remain haphazard toward high speeds, creating
exceptional friction during downhill braking - and for this reason, many users use gloves outdoors.
For users with multiple sclerosis, cerebral palsy, and muscular dystrophy, where arm strength
is sufficient for propulsion, but hand grip is limited, vinyl-coated handrims can dramatically facilitate
For those with exceptionally limited grip, as with quadriplegics, projection handrims allow true palming
- that is, rather than wrapping one's hand around a handrim, there are nubs to palm against (a bit like
a ship's wheel, you might say). The projections vary in size, location, and frequency, from vertical
or oblique, 1" to 3" in length, and 7 to 12 per wheel. And, it's these factors that can lead consumers
and providers alike wondering which configuration is best?|
There are no steadfast rules, as the
best projection set-up is based on individual needs; however, there are some universal aspects to consider.
Projections are available in vertical (straight up), or oblique (a 15- or 45-degree angle off the pushrim).
The advantage of vertical is that the projections don't protrude wider than a standard handrim. However,
while oblique does stem outward from the side of the handrim, the projections are more accessible (as
opposed to close to the tire like vertical projections). In most cases, it's somewhat more ergonomic
to palm an oblique rather than a vertical projection.
No matter if vertical or oblique, the height
of the projection is primarily based on the user's preferred grip, with short projections best suited
for palming, and long projections best for hooking (catching the projection in the web of one's thumb).
And, the number of projections is based on the frequency of one's push stroke - that is, one with a
longer push stroke can get by with fewer projections than someone with less travel in a push stroke.
Put simply, a fast-pushing quad with a long push stroke and palm skill may best benefit from 8, 1",
45-degree oblique projections, whereas a more involved quad who hooks his projections may benefit from
12, 3", 15-degree oblique projections.
Fortunately, projections handrims are an easy trial
- with quick-release wheels popped on and off - so if there's any doubt toward the best configuration,
request demonstration samples for an accurate assessment.
Ergonomic handrims are presently gaining attention, but truly aren't new. In fact, ergonomic handrims
date back to the early 1980's, originally explored by the U.S. Veterans Administration. Having an elongated
shape rather than round, ergonomic handrims are designed to require less grip, provide increased leverage,
and decrease joint stress. And, they work well, providing a more natural feel than a round tube.|
One aspect to note is that due to the increased size and non-tubular design, some ergonomic handrims
can add several pounds to a chair - affecting propulsion efficiencies by adding weight - so, consider
each product individually, and understand any trade-offs.
Self-propulsion is never easy.
And, for those with less than ideal grips, it is even more challenging. Nevertheless, if you're one
with limited dexterity, but still wish to propel yourself closer to the speed of life, there's probably
a vinyl-coated, projection, or ergonomic handrim surface that's right for you.