Article

In unilateral transtibial amputees maintenance of standing balance is compromised
due to the lack of active ankle control in the prosthetic limb.
The purpose of
this study is to disentangle the contribution of the prosthetic and sound limb to
balance control following waist-pull perturbations. We compared the contribution
of the hip and ankle joints to balance control of 15 unilateral transtibial
amputees and 13 able-bodied controls after been externally perturbed through
release of a pulling force. Perturbations were applied in four different
directions. Outcome measure was the proportion of joint moment integrated over
time generated by the hip and ankle joints in order to restore static stability
after perturbation. Analyses revealed that perturbations in backward/forward
direction were recovered mainly by the ankle strategy. The amputees compensated
for the absence of active ankle control in the prosthetic limb by increasing the
ankle moment in the sound limb. Interestingly, the passive properties of the
prosthetic foot contributed to balance control, which has important implications
for prosthetic fitting and standing stability in lower limb amputees. Amputees
and controls resisted perturbations in medio-lateral direction by generating the
necessary hip moments. Finally, these findings are discussed with respect to
prosthetic design and rehabilitation processes.
CI - Copyright (c) 2012 Elsevier B.V. All rights reserved.

Langue : ANGLAIS