Ankle and Knee Motions During Cross-Slope Walking for Slope-Adaptive Walking Aids

The aging of workers has recently become a social problem. The aim of this study is to conduct gait analyses on ankles and knee joints on cross-slopes to design walking aids for uneven terrains. To evaluate the motions of ankle and knee joints, we conducted slope-transverse gait (cross-slope walk) experiments on three healthy subjects at three slope angles (averagely 9°, 16°, and 30°). We measured the flexion-extension angles of the knees and the dorsiflexion-plantarflexion and eversion-inversion angles of the ankles using electric goniometers. The results of the experiment show that there are some different points between the motions of the knees and ankles in the upper-/lower-sides. For the 16° and 30° slopes, the upper knees have been maintained flexion without returning to the neutral positions. Furthermore, the lower ankles have been maintained inversion without returning to the neutral positions, and planter flexion is predominant.