Elucidation of Features that Express Gait Dynamics in Elderly People, and Influencing Factors

Abstract

The authors compared the gait dynamics between elderly and young people in conjunction with integrated electromyogram analysis in order to create basic guidelines pertaining to designing effective stumbling-resistant socks. The targeted leg joints were the joints of the knees, toes, and ankle. Through motion analysis, the authors compiled gait cycle curves for the angles, angular velocity, and angular acceleration of each joint. Upon examining these curves, the authors extracted features that expressed gait dynamics. The differences (ΔS) between the maximum and the minimum values were extracted. Characteristic features of gait in the elderly were observed in the joints of the ankles, rather than in the joints of the knees or the toes. A positive correlation was observed between the stride lengths and the ΔS of angular velocity of the ankle joints: elderly people with small ΔS values had shorter strides. Furthermore, the main agonist muscles used during gait were not identified through the electromyogram. By contrast, elderly people with larger ΔS values had longer strides, and the tibialis anterior and the gastrocnemius medial head were found to be the main agonist muscles. These findings suggest that ΔS of the angular velocity of the ankle joints may be a useful index in designing stumbling-resistant socks.