Delp S L, Arnold A S, Speers R A, Moore C A
Rehabilitation Institute of Chicago, IL 60611, USA.
J Orthop Res. 1996 Jan;14(1):144-51. doi: 10.1002/jor.1100140123.
Crouch gait, one of the most common movement abnormalities among children with cerebral palsy, is characterized by persistent flexion of the knee during the stance phase. Short hamstrings are thought to be the cause of crouch gait; thus, crouch gait is often treated by surgical lengthening of the hamstrings. In this study, a graphics-based model of the lower extremity was used in conjunction with three-dimensional kinematic data obtained from gait analysis to estimate the lengths of the hamstrings and psoas muscles during normal and crouch gaits. Only three of 14 subjects with crouch gait (four of 20 limbs with knee flexion of 20 degrees or more throughout stance) had hamstrings that were shorter than normal by more than 1 SD during walking. Most (80%) of the subjects with crouch gait had hamstrings of normal length or longer, despite persistent knee flexion during stance. This occurred because the excessive knee flexion was typically accompanied by excessive hip flexion throughout the gait cycle. All of the subjects with crouch gait had a psoas that was shorter than normal by more than 1 SD during walking. These results emphasize the need to consider the geometry and kinematics of multiple joints before performing surgical procedures aimed at correcting crouch gait.
蹲伏步态是脑瘫患儿中最常见的运动异常之一，其特征是在站立期膝关节持续屈曲。腘绳肌短被认为是蹲伏步态的原因；因此，蹲伏步态常通过手术延长腘绳肌来治疗。在本研究中，基于图形的下肢模型与从步态分析中获得的三维运动学数据相结合，以估计正常步态和蹲伏步态期间腘绳肌和腰大肌的长度。在14名有蹲伏步态的受试者中，只有3名（在整个站立期膝关节屈曲20度或更多的20条肢体中的4条）在行走时腘绳肌比正常短超过1个标准差。大多数（80%）有蹲伏步态的受试者腘绳肌长度正常或更长，尽管在站立期膝关节持续屈曲。这是因为在整个步态周期中，过度的膝关节屈曲通常伴随着过度的髋关节屈曲。所有有蹲伏步态的受试者在行走时腰大肌都比正常短超过1个标准差。这些结果强调在进行旨在纠正蹲伏步态的手术之前，需要考虑多个关节的几何形状和运动学。
