Article

Crouch gait, a common walking pattern in individuals with cerebral palsy, is
characterized by excessive flexion of the hip and knee.
Many subjects with crouch
gait experience knee pain, perhaps because of elevated muscle forces and joint
loading. The goal of this study was to examine how muscle forces and compressive
tibiofemoral force change with the increasing knee flexion associated with crouch
gait. Muscle forces and tibiofemoral force were estimated for three unimpaired
children and nine children with cerebral palsy who walked with varying degrees of
knee flexion. We scaled a generic musculoskeletal model to each subject and used
the model to estimate muscle forces and compressive tibiofemoral forces during
walking. Mild crouch gait (minimum knee flexion 20-35 degrees ) produced a peak
compressive tibiofemoral force similar to unimpaired walking; however, severe
crouch gait (minimum knee flexion>50 degrees ) increased the peak force to
greater than 6 times body-weight, more than double the load experienced during
unimpaired gait. This increase in compressive tibiofemoral force was primarily
due to increases in quadriceps force during crouch gait, which increased
quadratically with average stance phase knee flexion
(i.e., crouch severity).
Increased quadriceps force contributes to larger tibiofemoral and patellofemoral
loading which may contribute to knee pain in individuals with crouch gait.
CI - Copyright (c) 2011 Elsevier B.V. All rights reserved.

Langue : ANGLAIS