行走支撑期足弓变化规律与足功能转换机制

Changing Law of Foot Arch and Mechanism of Foot Function Transformation in Support Phase During Walking

目的 通过分析行走步态参数和足弓力学结构,探究行走支撑期足弓功能的转化机制及变化规律。方法 利用动作捕捉系统及足底压力测试系统同步采集8名受试者不同步速行走时的步态参数及横、纵弓角度。使用单因素重复测量方差分析检验不同步速下足横、纵弓角度变化及足底受力的特征值差异。结果 行走支撑期,纵弓角度、横弓角度及足底受力曲线均存在两个特征值,3条曲线特征值在4种步速下存在一致性规律。1.4倍和1.2倍最适速度行走时,蹬伸离地阶段时长显著性高于0.8倍最适速度(P<0.05),横弓升高的拐点和第1个受力峰值出现时间早于0.8倍最适步速(P<0.05);1.4倍最适步速相比于0.8倍最适速度横弓在蹬伸离地阶段的最小角度显著性增加(P<0.05),最小角度出现的时间显著性提前(P<0.05);1.2倍最适速度步行时,纵弓第2个峰值出现的位置相比于最适速度提前(P<0.05)。结论 行走支撑期,足以纵弓、横弓升降实现功能转化。足纵弓和足横弓共同降低完成缓冲,纵弓降低、横弓升高使足增加刚性完成蹬伸。在执行蹬伸推进功能时,步速增加会加大蹬伸离地阶段在步态支撑期的时间占比,足横弓和纵弓的变化随蹬伸期提前。探究足弓变化及足功能转化机制对了解足部运动规律及足踝康复具有重要的指导意义。

Objective To explore the transformation mechanism and changing law of foot arch function in support phase during walking through the analysis of gait parameters and foot arch mechanical structures. Methods Gait parameters, transverse and longitudinal arch angles of 8 subjects at different walking speeds were collected synchronously by motion capture system and plantar pressure test system. One-way repeated measure anova was used to test differences in characteristic values of foot transverse and longitudinal arch angles as well as plantar forces at different speeds. Results In support phase, two eigenvalues appeared in curve of longitudinal arch angle, transverse arch angle and plantar force, and the eigenvalues of three curves were consistent at four types of walking speeds. During walking at 1.4 and 1.2 times of the optimum speed, the time of push-off stage was significantly longer than that at 0.8 times of the optimal speed(P<0.05). The inflection point and the first peak of the transverse arch appeared earlier than those at 0.8 times of the optimal speed(P<0.05). The minimum transverse arch angle at 1.4 times of the optimal speed was significantly larger than that at 0.8 times of the optimal speed(P<0.05), while the time when the minimum angle appeared was significantly earlier(P<0.05). During walking at 1.2 times of the optimal speed, the position for the second peak of the longitudinal arch appeared earlier than that at the optimal speed(P<0.05).Conclusions In support phase during walking, foot function transformation was realized by both the longitudinal arch and transverse arch. The longitudinal and transverse arch of the foot were lowered to complete buffer function, and the longitudinal arch of the foot was lowered while the transverse arch was raised to increase foot stiffness to complete the push-off function. The faster pace would increase time proportion of the push-off stage in support phase, while the change of the transverse arch and longitudinal arch was advanced. Exploring the change of foot arch and the mechanism of foot function transformation has important guiding significance for understanding the law of foot movement as well as ankle rehabilitation.