约束复合踝关节运动对人体步态稳定性的影响

Influence of Restricting the Ankle Joint Complex Motions on Gait Stability of Human Body

本文目的是研究约束复合踝关节内(外)翻和旋内(外)运动对人体步态稳定性的影响。试验在水平湿滑试验台上进行,对比了约束复合踝关节内(外)翻和旋内(外)运动(FIXED)以及无束缚(FREE)两种状态,分析了时-空步态参数、运动学参数、动力学参数以及利用摩擦系数(UCOF)。试验结果表明FIXED可能会导致步速和跨步长显著增大,双支撑期显著缩短。同时,FIXED可影响膝关节和踝关节的关节角度在矢状面内的运动幅度。另外,约束后利用摩擦系数显著增大,这反映了滑跌概率的增大以及步态稳定性的减弱。因此,在助行器、双足机器人或者假肢设计中,应该进行结构设计以实现复合踝关节内(外)翻及旋内(外)运动。

The purpose of this study is to determine how restricting inversion-eversion and pronation-supination mo- tions of the ankle joint complex influences the stability of human gait. The experiment was carried out on a slippery level ground walkway. Spatiotemporal gait parameter, kinematics and kinetics data as well as utilized coefficient of friction （UCOF） were compared between two conditions, i.e. with restriction of the ankle joint complex inversion-e- version and pronation-supination motions （FIXED） and without restriction （FREE）. The results showed that FIXED could lead to a significant increase in velocity and stride length and an obvious decrease in double support time. Fur- thermore, FIXED might affect the motion angle range of knee joint and ankle joint in the sagittal plane. In FIXED condition, UCOF was significantly increased, which could lead to an increase of slip probability and a decrease of gait stability. Hence, in the design of a walker, bipedal robot or prosthetic, the structure design which is used to achieve the ankle joint complex inversion-eversion and pronation-supination motions should be implemented.