Biomechanics of the human walk-to-run gait transition in persons with unilateral transtibial amputation.
Biomechanics of the human walk-to-run gait transition in persons with unilateral transtibial amputation.
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DOI：
10.1016/j.jbiomech.2016.04.004
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发表时间：
2016-06-14
影响因子：
2.4
通讯作者：
Chang YH
中科院分区：
文献类型：
--
作者：
Giest TN;Chang YH
已经证明，推进力的产生（足底屈肌肌肉的内力-长度-速度特性的指示）是人类步行到跑步过渡的主要决定因素。这项工作的目的是确定的步态过渡速度的人与单侧，穿胫骨截肢被动弹性假体，并评估其完整的侧跖屈肌肌肉的机械限制是否是一个主要的决定因素，他们的步行到运行的过渡。我们通过增量协议确定每个人的步态过渡速度（GTS），并在步态过渡速度（100%：GTS）的50%，60%，70%，80%，90%，100%，120%和130%的速度下步行时评估动力学和运动学。单侧经胫骨截肢者在步态之间转换的绝对速度明显低于匹配的健全对照组（分别为1.73±0.13和2.09±0.05m/s，p<0.01）。峰值前后推进力增加速度控制，直到100%的首选步态过渡速度，并在更大的速度下降。120%GTS时前后推进力产生显著降低（110%：0.27±0.04 > 120%：0.23±0.05BW，p<0.05）。相比之下，截肢受试者的完整侧在以高于其优选步态过渡速度的速度行走时产生显著更高的峰值前后推进力（100%：0.28±0.04 < 110%：0.30±0.04BW，p<0.05）。在推进力生产的变化被认为是一个函数的变化，绝对速度，而不是相对于步行到运行的过渡速度。因此，单侧经胫骨截肢者从步行到跑步的过渡不太可能由完整侧跖屈肌的推进力产生或力-长度-速度特性决定。
Propulsive force production (indicative of intrinsic force-length-velocity characteristics of the plantar flexor muscles) has been shown to be a major determinant of the human walk-to-run transition. The purpose of this work was to determine the gait transition speed of persons with unilateral, transtibial amputation donning a passive-elastic prosthesis and assess whether a mechanical limit of their intact side plantar flexor muscles is a major determinant of their walk-to-run transition. We determined each individual’s gait transition speed (GTS) via an incremental protocol and assessed kinetics and kinematics during walking at speeds 50, 60, 70, 80, 90, 100, 120, and 130% of that gait transition speed (100%:GTS). Unilateral, transtibial amputees transitioned between gaits at significantly slower absolute speeds than matched able-bodied controls (1.73±0.13 and 2.09±0.05m/s respectively, p<0.01). Peak anterior-posterior propulsive force increased with speed in controls until 100% of the preferred gait transition speed and decreased at greater speeds. A significant decrease in anterior-posterior propulsive force production was found at 120%GTS (110%: 0.27±0.04 > 120%: 0.23±0.05BW, p<0.05). In contrast, amputee subjects’ intact side generated significantly higher peak anterior-posterior propulsive forces while walking at speeds above their preferred gait transition speed (100%: 0.28±0.04 < 110%: 0.30±0.04BW, p<0.05). Changes in propulsive force production were found to be a function of changes in absolute speed, rather than relative to the walk-to-run transition speed. Therefore, the walk-to-run transition in unilateral, transtibial amputees is not likely dictated by propulsive force production or the force-length-velocity characteristics of the intact side plantar flexor muscles.