不同侧切角度和触地模式下膝关节内部应力的有限元分析

Finite element analysis of internal knee joint stresses under different side-cut angles and ground contact modes

目的:基于已验证的膝关节有限元模型,分析不同侧切角度和触地模式下的膝关节生物力学特征,为足球运动员预防侧切运动损伤和损伤后制定康复训练方案提供理论依据。方法:采集15名男子足球运动员(均为国家二级运动员水平及以上)在6m/s±10%的速度下以前、后触地模式进行45°、90°、135°的侧切运动,通过Visual 3D软件计算膝关节运动学、动力学数据,基于已验证的膝关节模型分别对6种触地动作中地面反作用力峰值时刻做数值仿真。结果:①侧切角度与膝关节屈曲峰值角度正相关(P<0.05),即侧切角度增大时,膝关节屈曲峰值角度随之增大,垂直地面反作用力随侧切角度呈现出显著性的相反趋势(P<0.05);②前足触地和后足触地在运动学和动力学上存在显著差异(P<0.05)。前足触地模式下,膝关节屈曲角度、外翻和内旋峰值角度较大,伴随着较大的向上地面反作用力;③侧切触地时刻,半月板Von Mises应力和股骨软骨接触应力分布情况呈现出与侧切角度和触地模式相关的特征。在90°后足触地模式中,内侧半月板体部外缘和内侧股骨软骨出现了明显的应力集中,这可能预示着在此条件下膝关节损伤风险的增加。结论:后足触地模式进行90°角度侧切可能导致膝关节内部应力失衡,特别是在内侧半月板外缘产生显著的应力集中,提示存在较大损伤风险。

Objective:To analyze the biomechanical characteristics of the knee joint under different lateral cut angles and ground contact modes using the validated finite element model of the knee joint,which provided a theoretical basis for preventing lateral cut sports injuries in football players and formulating rehabilitation training programs after injury.Method:Fifteen male football players(all of whom are national second-level athletes and above)were recruited to perform cutting movements at the angles of 45°,90°and 135°in front and rear touchdown modes at a speed of 6m/s±10%.The kinematics and dynamics data of the knee joint were calculated by Visual 3D software,and the peak moment of ground reaction force in the six touchdown actions was numerically simulated based on the verified knee joint model.Result:①The cutting angle is positively correlated with the peak knee flexion angle(P<0.05),indicating that as the cutting angle increases,while vertical ground reaction force decreases significantly with increase cutting angle(P<0.05).②Significant differences in kinematics and dynamics exist between forefoot and rearfoot striking(P<0.05).In the forefoot striking mode,there are larger knee flexion angles,external rotation,and internal rotation peak angles,along with higher upward ground reaction force.③At the moment of side cutting contact,the distribution of Von Mises stress in the meniscus and the contact stress in the femoral cartilage show characteristics related to the cutting angle and the mode of foot contact.In the 90°rearfoot striking mode,there is a noticeable concentration of stress on the external edge of the medial meniscus and the medial femoral cartilage,which may indicate an increased risk of knee joint injury under these conditions.Conclusion:Performing a 90°cut with a rearfoot striking pattern may lead to an imbalance in internal knee joint stress,particularly causing significant stress concentration on the external edge of the medial meniscus,indicating a higher risk of injury.