Patterns of relations between lower limb angle excursions during normal gait

Abstract

This paper deals with the analysis of data from a kinematic study of limb angle during normal gait. The first set of data deals with the variation of femur angle to the vertical, and of knee and ankle flexion-extension. The data are recorded on the System of Gestual Automatic 3D Analysis with a 50 Hz sampling rate. The second data set concerns morphological parameters. The data are obtained from 35 subjects. The time angle data are raw and are not to be related to a base position. The first stage of the angle analysis shows that a walking cycle can be characterized by 25 values. A factor analysis is then applied to these values for each angle in order to underscore the more informative instants. From this study, eight measurements are preserved. In the third stage, the same method is applied to both angles. It illustrates four ways to differentiate healthy subjects' walk. It also shows that the angles of femur and knee are strongly correlated and that there is a priori no clear relationship between the ankle and the two previous angles. The last stage is analysis of the morphological and angle parameters together. It brings to the fore the influence of sex and height for two groups of subjects.