目的 探讨预期条件下不同角度侧切触地过程中的膝关节运动学特征、地面反作用力(Ground reaction Force, GRF)特征以及软骨和半月板的应力状态。方法 使用Vicon及测力台采集14名受试者在预期条件下分别进行45°、90°和135°侧切时的运动学数据和GRF,通过Visual3D逆动力学计算获取膝关节反力,基于膝关节三维有限元模型分别对三种侧切角度的触地过程进行数值仿真。结果 预期条件下三种侧切角度在触地过程中的膝关节运动学特征存在显著性差异(p＜0.001),膝关节屈曲程度随侧切角度增大而增加；vGRF随侧切角增加而显著减小(p＜0.001),hGRF呈现出相反的趋势；三种侧切角度中,90°侧切时髌骨软骨以及股骨软骨接触应力峰值较大(6.36MPa；8.22MPa), ACL接触点主应力峰值较大(17.47MPa),其次为135°和45°；三种侧切角度下外侧股骨软骨接触应力峰值均大于内侧。结论 提示90°侧切运动时膝关节损伤风险更大,135°侧切时膝关节内部的应力状态与90°相比较为良好,预期条件下膝关节损伤风险并不随侧切角增大而升高。
Purpose To investigate the knee kinematics characteristics, ground reaction force (GRF) characteristics, and the stress state of cartilage and meniscus in the process of lateral incisions with different angles. Method Vicon and dynamometer were used to collect kinematics data and GRF of 14 subjects in 45 °, 90 ° and 135 ° cutting angle respectively under the expected conditions. The knee joint reaction force was obtained through the inverse dynamics calculation of visual3d. Based on the three-dimensional finite element model of knee joint, the contact process of three kinds of lateral cutting angles was simulated. Results Under the expected conditions, there were significant differences in knee joint kinematics characteristics among the three kinds of cutting angles during touchdown(p＜0.001), the degree of knee flexion increases with the increase of lateral cutting angle; The vGRF decreased significantly with the increase of lateral cutting angle (p＜0.001), hGRF showed the opposite trend; Among the three kinds of lateral cutting angles, the peak contact stress of patellar cartilage and femoral cartilage was larger at 90 ° cutting angle (6.36MPa；8.22MPa), the peak value of principal stress at ACL contact point was also larger at 90 ° cutting angle(17.47MPa), the second was 135 ° and 45 ° respectively; the peak contact stress of lateral femoral cartilage was greater than that of medial femoral cartilage at three cutting angles. Conclusion It is suggested that the risk of knee joint injury is higher in 90 ° cutting angles, and the stress state of knee joint in 135 ° cutting angles is better than that in 90 ° cutting angles, and the risk of knee joint injury does not increase with the increase of cutting angle under the expected conditions.