膝关节肌肉力分布模拟研究

Muscle Force Distribution Model of Knee Joint

本研究建立了膝关节肌肉力分布模型。通过调整肌肉最大应力使模拟肌肉合力矩与文献关节合力矩误差最小化的数学优化方法标定肌肉参数,从而解决肌肉参数个体差异大的问题,同时,使用敏感度分析得到肌肉最优长度对肌肉力的影响。研究结果表明,通过优化计算出肌肉合力矩与文献数据高度相关,股四头肌和股后肌群预测结果的复相关系数分别为0.95和0.92;使用优化方法获得的股四头肌与股后肌群的最大应力分别为52.4N/cm2和53.8N/cm2;敏感度分析的结果表明肌肉最优长度对肌力模拟具有显著影响,因此,文献平均肌肉长度数据不适用于个体化肌肉力分布模型。

In this study,a muscle force distribution model of knee joint is established.Muscle length and moment arm were determined from the anatomical model of the lower limb.The results of simulations using generic muscle parameters may not be valid since muscle properties vary from subject to subject.In order to solve this problem,the model calibrated muscle stress using mathematical optimisation to match the net flexion/extension muscle moment with those data from literatures.Sensitivity analyses were also performed to assess the effect of optimum muscle length on estimated muscle contraction force.The result of the study showed a good relationship between optimized muscle moment and knee resultant flexion-extension moment.The joint moments were predicted with multiple correlation coefficient 0.95 for quadriceps and 0.92 for hamstrings.The muscle stresses of the quadriceps and hamstrings obtained through the optimization procedure are 52.4 and 53.8 N/cm2 respectively.Our results of sensitivity analysis also suggest it is especially important to use accurate values of optimal muscle length.The data of optimum muscle length from literature is not valid for subject-specific modeling.