Article

Mechanical impedance of the ankle is known to influence key aspects of ankle
function. We investigated the effects of robot-assisted ankle training in people
with chronic stroke on the paretic ankle's passive stiffness and its relationship
to overground gait function. Over 6 wk, eight participants with residual
hemiparetic deficits engaged in a visuomotor task while seated that required
dorsiflexion (DF) or plantar flexion (PF) of their paretic ankle with an ankle
robot ("anklebot") assisting as needed. Passive ankle stiffness (PAS) was
measured in both the trained sagittal and untrained frontal planes. After 6 wk,
the PAS decreased in both DF and PF and reverted into the variability of
age-matched controls in DF. Changes in PF PAS correlated strongly with gains in
paretic step lengths (Spearman rho = -0.88, p = 0.03) and paretic stride lengths
(Spearman rho = -0.82, p = 0.05) during independent floor walking. Moreover,
baseline PF PAS were correlated with gains in paretic step lengths (Spearman rho
= 0.94, p = 0.01), paretic stride lengths (Spearman rho = 0.83, p = 0.05), and
single-support stance duration (Spearman rho = 0.94, p = 0.01); and baseline
eversion PAS were correlated with gains in cadence (Spearman rho = -0.88, p =
0.03). These findings suggest that ankle robot-assisted, visuomotor-based,
isolated ankle training has a positive effect on paretic ankle PAS that strongly
influences key measures of gait function.

Langue : ANGLAIS