Article

OBJECTIVE: To evaluate the effect of backrest height on wheelchair propulsion
kinematics and kinetics. DESIGN: An intervention study with repeated measures.
SETTING: University laboratory. PARTICIPANTS: Convenience sample included manual
wheelchair users (N=36; 26 men and 10 women) with spinal cord injuries ranging
from T8 to L2. INTERVENTION: Participants propelled on a motor-driven treadmill
for 2 conditions (level and slope of 3 degrees ) at a constant speed of 0.9 m/s
while using in turn a sling backrest fixed at 40.6 cm (16 in) high (high
backrest) and a lower height set at 50% trunk length (low backrest). MAIN OUTCOME
MEASURES: Cadence, stroke angle, peak shoulder extension angle, shoulder
flexion/extension range of motion, and mechanical effective force. RESULTS:
Pushing with the low backrest height enabled greater range of shoulder motion
(P<.01), increased stroke angle (P<.01), push time (P<.01), and reduced cadence
(P=.01) regardless of whether the treadmill was level or sloped. CONCLUSIONS: A
lower cadence can be achieved when pushing with a lower backrest, which decreases
the risk of developing upper-limb overuse related injuries. However, postural
support, comfort, and other activities of daily living must also be considered
when selecting a backrest height for active, long-term wheelchair users. The
improvements found when using the low backrest were found regardless of slope
type. Pushing uphill demanded significantly higher resultant and tangential
force, torque, mechanical effective force, and cadence.
CI - Copyright (c) 2012 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS