



Among the toughest, most circular arguments in the mobility field regards footplates being too close
to the ground for users' preference. And, such conversations go like this:
I want to raise my
wheelchair's footplate higher for more ground clearance, says the consumer.
The only way to
accomplish that is to raise your entire seat-to-floor height since it's a fixed distance between your
seat and footplate, based on your leg length, replies the provider.
But, I can't have a taller
seat-to-floor height because then my knees won't fit under tables, and transfers will be hard, says
the consumer.
Then you can't increase your footplate clearance, says the provider.
But,
I want to, replies the consumer.
Then you're OK with a taller seat-to-floor height? the provider
asks.
No, says the consumer.
....And, the conversation goes on forever!
The fact
is, on power and manual wheelchairs alike, among the few fixed distances is between the seat pan and
footplate, based on one's knee-to-heel lower leg length. It's a formally fit dimension, optimizing positioning
and pressure management and it shouldn't be changed once set at the proper leg length.
As a
result, footplate height ties directly to seat height. Raise the seat height, and the footplate raises.
Lower the seat height, and the footplate lowers. And, in this way, if one wishes a low seat-to-floor
height, and has average to longer legs, the footplate is often close to the ground.
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Based on the illustration, we see the direct correlation between seat-to-floor height and footplate
clearance. In the example, a 16 leg length with an 18 seat-to-floor height equates to 2 of ground
clearance under the footplate. In order to get 4 of ground clearance under the footplate again, because
one's leg length stays 16 the entire seat must move upward, to a 20 seat-to-floor height. (If
one were only to move the footplate upwards, it would distort one's positioning.)
An alternative
is to use a lesser legrest angle, where one's feet are positioned outward and forward. However, most
users resist a 60-degree leg angle, for example, because it dramatically increases the overall length
of the wheelchair (one's feet protrude far forward).
On power wheelchairs with power elevating
foot platforms tucked close to a 90-degree angle when fully retracted, some users take issue with having
to elevate the foot platform or slightly tilt the seat for outdoor clearance. However, again, footplate
clearance directly relates to seat-to-floor height, and if one does have a low seat-to-floor height,
footplate ground clearance may be compromised, requiring slightly elevating the foot platform or tilting
the seat in some cases when venturing on uneven terrain.
Therefore, if you've ever wondered
why you can't have both a low seat-to-floor height and maximum footplate clearance, now you know the
answer: Your leg length sets the rule.
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Published 5/2011, Copyright 2011, WheelchairJunkie.com
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