Article

OBJECTIVE: To determine if the level of effort in paretic plantar flexors during
gait could be a factor in explaining locomotor asymmetry. DESIGN: Cross-sectional
study. SUBJECTS: Twenty individuals with chronic stroke (mean age 49.4 years
(standard deviation 13.2). METHODS: Participants walked on a split-belt treadmill
for 3 periods: baseline at self-selected speed; adaptation with the belt speed
doubled on the non-paretic side; and post-adaptation at self-selected speed.
Kinematic and kinetic data were recorded. The efforts were estimated with the
muscular utilization ratio. Pearson correlation coefficients were used to assess
the relationships between the paretic plantar flexor level of effort at baseline
and changes in spatiotemporal gait parameters and joint moments after split-belt
treadmill walking. In addition, in a subgroup of 12 asymmetrical individuals,
paretic plantar flexor efforts were compared between periods (baseline
(asymmetrical) and post-adaptation (symmetrical)) with paired Student's t-tests.
RESULTS: Baseline level of effort in plantar flexors was negatively related to
changes in paretic plantar flexion moments (r = -0.70; p = 0.001) and changes in
non-paretic step length (r = -0.65; p = 0.003). A more symmetrical spatiotemporal
gait increased the paretic plantar flexor effort from 73.7% to 86.6% (p = 0.007).
CONCLUSION: A more symmetrical gait increases paretic plantar flexor efforts.
Individuals post-stroke presenting high plantar flexor efforts when walking have
limited muscle capacity to increase non-paretic step after split-belt walking.

Langue : ANGLAIS