The effect of asymmetrical gait induced by unilateral knee brace on the knee flexor and extensor muscles.

Abstract

Asymmetrical stiff knee gait is a mechanical pathology that can disrupt lower extremity muscle coordination. A better understanding ofthis condition can help identify potential complications. This study proposes the use ofdynamic musculoskeletal modelling simulation to investigate theeffect of induced mechanical perturbation onthe kneeand to examine the musclebehaviour without invasive technique. Thirty-eighthealthy participants were recruited. Asymmetrical gait was simulated using knee brace. Knee joint angle, jointmoment and knee flexor and extensor muscle forces were computed using OpenSim. Differences inmuscle force between normal and abnormal conditions were investigated using ANOVA and Tukey-Kramer multiple comparison test.The results revealed that braced knee experienced limited range of motion withsmallerflexion momentoccuring atlate swing phase. Significant differences were found in all flexormuscle forces and in several extensor muscle forces (p<0.05). Normal knee produced larger flexormuscle force than braced knee. Braced knee generated the largest extensormuscle force at early swing phase. In summary, musculoskeletalmodelling simulation can be a computational tool to map and detect thedifferences between normal and asymmetrical gaits.