MUSCLE FUNCTION IN DEFORMED AND SURGICALLY ALTERED LIMBS

描述（改编自申请人的摘要）： 为治疗蹲姿步态提供科学依据， 痉挛性双瘫患者中最常见的运动异常。 蹲伏步态的特征是膝盖持续屈曲， 通常伴有过度屈曲、内收和内旋， 臀部 这是一种效率极低的运动方式;如果不是这样， 纠正它往往会导致关节退化。 虽然手术，如： (i)（二）股骨头的去旋转;（三） 经常进行股直肌的转移， 改善肌肉骨骼功能，这些手术的结果是 不可预测，往往不令人满意，使患者严重， 终身的身体限制。 这项工作的目的是发展 生物力学模型解释了蹲姿步态的原因，并预测了 常用手术治疗的功能后果。 目标1将检查膝关节过度屈曲的原因。 基于 根据初步数据，假设许多具有蹲伏步态的人 腿筋有足够的长度正常行走。 这一假设 将通过估计正常情况下的腿筋长度进行测试， 使用详细的肌肉骨骼模型结合 测量三维关节运动学。 这一分析可以使 更合理的基础来决定谁应该，谁不应该， 腿筋延长。 目标#2将检查原因和纠正措施 髋关节过度内旋 旋转力矩臂 将基于定量的 解剖学研究和三维计算机模型， 磁共振图像。 计算机模型将用于分析 股骨畸形和去旋转截骨术对 肌肉的旋转功能。 这一分析旨在揭示 恢复肢体正常旋转的最佳方法。 目标#3将比较 在将股直肌转移到 手术的电脑模拟 这项研究还将确定， 受试者使用股直肌作为膝屈肌后，它是转移 膝盖后面。 申请人建议，虽然多关节 运动异常如蹲下步态异常复杂， 对正常人肌肉功能的定量描述， 畸形的，手术改变的肢体，正如这里提出的，是一个重要的 也是设计更有效治疗方法的第一步

DESCRIPTION (Adapted from the Applicant's Abstract): The long-term goal of this work is to provide a scientific basis for treating crouch gait, the most common movement abnormality among persons with spastic diplegia. Crouch gait is characterized by persistent flexion of the knee, which is usually accompanied by excessive flexion, adduction and internal rotation of the hip. It is an extremely inefficient means of locomotion; if not corrected it often leads to joint degeneration. Although surgeries such as: (i) lengthening of the hamstrings; (ii) derotation of the femur; and (iii) transfer of the rectus femoris are frequently performed in an attempt to improve musculoskeletal function, the outcomes of these surgeries are unpredictable and often unsatisfactory, leaving patients with serious, life-long physical limitations. The purpose of this work is to develop biomechanical models that explain the causes of crouch gait and predict the functional consequences of commonly used surgical treatments. Aim #1 will examine the causes of excessive knee flexion. Based on preliminary data, it is hypothesized that many persons with crouch gait have hamstrings that are of adequate length for normal walking. This hypothesis will be tested by estimating the lengths of the hamstrings during normal and crouch gait using detailed musculoskeletal models in conjunction with measured three-dimensional joint kinematics. This analysis may enable a more rational basis to be developed for deciding who should, and should not, have hamstring lengthening. Aim #2 will examine the causes and corrections of excessive internal rotation of the hip. The rotational moment arms of the muscles crossing the hip will be determined based on quantitative anatomical studies and three dimensional computer models constructed from magnetic resonance images. The computer models will be used to analyze the effects of femoral deformities and derotational osteotomies on the rotational function of the muscles. This analysis is intended to reveal the best means to restore normal limb rotation. Aim #3 will compare measurements taken from subjects after transfer of the rectus femoris to a computer simulation of the surgery. This study will also determine if subjects use the rectus femoris as a knee flexor after it is transferred behind the knee. It is suggested by the applicant that although multijoint movement abnormalities such as crouch gait are exceptionally complex, the development of quantitative descriptions of muscle function in normal, deformed, and surgically altered limbs, as proposed here, is an important and necessary first step toward designing more effective treatments.