A Basic Study on Evaluation of Abnormal Foot Movements in Hemiplegic Gait Using Inertial Sensors

Abstract

In this study, a method of evaluating abnormal foot movements during gait of hemiplegic patients using inertial sensors was examined, because abnormal foot movements may cause the falling during walking. First, gait of normal subjects was measured with inertial sensors attached to the feet, and angle ranges on a two-dimensional plane consisting of angles in the sagittal plane at the initial contact and in the frontal plane at the beginning of the foot flat in the sagittal plane was created as an evaluation criterion using Mahalanobis distance. Then, an evaluation score was calculated by angles from the center of the angle range and Mahalanobis distance. Foot movements of hemiplegic subjects were evaluated by the Euclidean distance from the center of the angle range comparing with those of normal subjects. Different abnormal movements were obtained in each hemiplegic subject. It is necessary to study evaluation of angle plot distribution.