Anderson Frank C, Goldberg Saryn R, Pandy Marcus G, Delp Scott L
Department of Mechanical Engineering, Stanford University, Stanford, CA 94305-4038, USA.
J Biomech. 2004 May;37(5):731-7. doi: 10.1016/j.jbiomech.2003.09.018.
A three-dimensional dynamic simulation of walking was used together with induced position analysis to determine how kinematic conditions at toe-off and muscle forces following toe-off affect peak knee flexion during the swing phase of normal gait. The flexion velocity of the swing-limb knee at toe-off contributed 30 degrees to the peak knee flexion angle; this was larger than any contribution from an individual muscle or joint moment. Swing-limb muscles individually made large contributions to knee angle (i.e., as large as 22 degrees), but their actions tended to balance one another, so that the combined contribution from all swing-limb muscles was small (i.e., less than 3 degrees of flexion). The uniarticular muscles of the swing limb made contributions to knee flexion that were an order of magnitude larger than the biarticular muscles of the swing limb. The results of the induced position analysis make clear the importance of knee flexion velocity at toe-off relative to the effects of muscle forces exerted after toe-off in generating peak knee flexion angle. In addition to improving our understanding of normal gait, this study provides a basis for analyzing stiff-knee gait, a movement abnormality in which knee flexion in swing is diminished.
采用步行的三维动态模拟结合诱导位置分析，以确定蹬离时的运动学条件以及蹬离后的肌肉力量如何影响正常步态摆动期的膝关节最大屈曲角度。摆动腿膝关节在蹬离时的屈曲速度对膝关节最大屈曲角度的贡献为30度；这比任何单个肌肉或关节力矩的贡献都要大。摆动腿的肌肉各自对膝关节角度有很大贡献（即高达22度），但它们的作用往往相互平衡，因此所有摆动腿肌肉的综合贡献很小（即小于3度的屈曲）。摆动腿的单关节肌肉对膝关节屈曲的贡献比摆动腿的双关节肌肉大一个数量级。诱导位置分析的结果明确了蹬离时膝关节屈曲速度相对于蹬离后施加的肌肉力量在产生膝关节最大屈曲角度方面的重要性。除了增进我们对正常步态的理解之外，本研究还为分析僵膝步态提供了基础，僵膝步态是一种摆动期膝关节屈曲减少的运动异常情况。
