Article

Uneven walking surfaces pose challenges to balance, especially in individuals
with lower extremity amputation. The purpose of this study was to determine if
lateral stability of persons with unilateral transtibial amputation (TTA) is
compromised when walking on a loose rock surface. Thirteen TTA and 15 healthy
controls walked over level ground and over a loose rock surface at four
controlled speeds. Dependent measures, including medial-lateral center of mass
(COM) motion, step width variability, lateral arm swing velocity, and mean and
variability of the minimum margins of stability (MOSmin), were compared between
subject groups and across conditions. TTA had greater average MOSmin than Control
subjects (p=0.018). TTA exhibited decreased MOSmin on their prosthetic limbs
compared to their intact limbs (p=0.036), while Control subjects did not exhibit
side to side differences. Both groups increased MOSmin with increasing walking
speed (p</=0.001). There was no difference in the average MOSmin between walking
surfaces (p=0.724). However, the variability of MOSmin was greater on the rocks
compared to level ground. Both subject groups increased step width, step width
variability, COM range of motion and peak COM velocity when walking on the rock
surface. TTA exhibited greater variability of both step width and MOSmin, which
suggests that they made larger step-to-step corrective responses, more often, to
achieve the same average result.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS