胫骨内侧应力在跑步运动过程中的计算机仿真分析

Computer simulation analysis of medial tibial stress during running

背景:内侧胫骨应力综合征是困扰跑步者的一种常见的下肢慢性损伤,其损伤机制可能与“肌肉牵引”假说有关,然而这种假说还没有得到完全的证实。目的:使用肌骨仿真系统和有限元分析等方法,考察比目鱼肌、胫骨后肌、趾长屈肌在跑步过程中的收缩特征是否与跑步时胫骨内侧缘的应力水平存在相关性,从而影响内侧胫骨应力综合征的发生与发展。方法:将6名受试者不同速度跑步时的动作捕捉数据输入Anybody Modeling System骨肌仿真系统,对2.5,3.5,4.5 m/s三种跑步速度情况下的步态支撑期进行逆动力学仿真,将仿真得到的边界条件与有限元模型结合,考察胫骨内侧的应力分布情况。使用偏最小二乘回归方法分析自变量(肌力、弹性势能)与因变量(胫骨应力)之间的相关性。结果与结论:①胫骨应力水平在支撑期(1%-50%)存在速度间的统计学差异(P=0.044,F=3.834,η_(p)^(2)=0.040);②3种速度下,比目鱼肌的肌力与胫骨应力之间的平均相关性最高(r=12.999),其次胫骨后肌肌力与胫骨应力的平均相关性排名第二(r=-10.735),然后依次是趾长屈肌肌力(r=-9.751),胫骨后肌弹性势能(r=8.012),比目鱼肌弹性势能(r=9.076),趾长屈肌弹性势能(r=-4.782);③结果表明,跑步速度的增加,胫骨应力水平随之上升;比目鱼肌的收缩及吸收的弹性势能在跑步过程中的释放对于内侧胫骨应力综合征的发展将产生不可忽略的影响,而胫骨后肌和趾长屈肌的作用被高估了;综合来看,研究支持了“肌肉牵引”假说中比目鱼肌的收缩对内侧胫骨应力综合征发展发挥作用的推论。

BACKGROUND:Medial tibial stress syndrome is a common chronic lower limb injury among runners,potentially linked to the“muscle traction theory.”However,this hypothesis has not been fully confirmed.OBJECTIVE:To investigate whether the contraction characteristics of the soleus,posterior tibialis,and flexor digitorum longus muscles during running are correlated with stress levels at the medial tibial border and influence the occurrence and development of medial tibial stress syndrome using musculoskeletal simulation systems and finite element analysis.METHODS:Motion capture data of six subjects running at different speeds were input into the Anybody Modeling System for inverse dynamic simulations during the stance phase at running speeds of 2.5,3.5,and 4.5 m/s.The calculated boundary conditions were combined with finite element models to examine the stress distribution on the medial tibia.Partial least squares regression was used to analyze the correlation between independent variables(muscle force and elastic potential energy)and the dependent variable(tibial stress).RESULTS AND CONCLUSION:(1)There were statistically significant differences in tibial stress levels across different speeds during the stance phase(1%-50%)(P=0.044,F=3.834,η_(p)^(2)=0.040).(2)Among the three speeds,the average correlation between soleus muscle force and tibial stress was the highest(r=12.999),followed by the correlation between posterior tibialis muscle force and tibial stress(r=-10.735),flexor digitorum longus muscle force(r=-9.751),posterior tibialis elastic potential energy(r=8.012),soleus elastic potential energy(r=9.076),and flexor digitorum longus elastic potential energy(r=-4.782).(3)The results indicate that with increasing running speed,tibial stress levels rise.The contraction of the soleus muscle and the release of absorbed elastic potential energy during running have a significant impact on the development of medial tibial stress syndrome,whereas the roles of the posterior tibialis and flexor digitorum longus muscles have been overestimated.Overall,the study supports the hypothesis that the contraction of the soleus muscle plays a crucial role in the development of medial tibial stress syndrome,consistent with the“muscle traction”hypothesis.