Liao Tzu-Chieh, Keyak Joyce H, Powers Christopher M
1 University of Southern California.
2 University of California, San Francisco.
J Appl Biomech. 2018 Aug 1;34(4):298-305. doi: 10.1123/jab.2017-0229. Epub 2018 Jul 11.
The primary purpose of this study is to determine whether recreational runners with patellofemoral pain (PFP) exhibit greater peak patella cartilage stress compared with pain-free runners. A secondary purpose was to determine the kinematic and/or kinetic predictors of peak patella cartilage stress during running. A total of 22 female recreational runners (12 with PFP and 10 pain-free controls) participated in this study. Patella cartilage stress profiles were quantified using subject-specific finite element models simulating the maximum knee flexion angle during the stance phase of running. Input parameters to the finite element model included subject-specific patellofemoral joint geometry, quadriceps muscle forces, and lower-extremity kinematics in the frontal and transverse planes. Tibiofemoral joint kinematics and kinetics were quantified to determine the best predictor of stress using stepwise regression analysis. Compared with the pain-free runners, those with PFP exhibited greater peak hydrostatic pressure (PFP vs control: 21.2 [5.6] MPa vs 16.5 [4.6] MPa) and maximum shear stress (PFP vs control: 11.3 [4.6] MPa vs 8.7 [2.3] MPa). Knee external rotation was the best predictor of peak hydrostatic pressure and peak maximum shear stress (38% and 25% of variances, respectively), followed by the knee extensor moment (21% and 25% of variances, respectively). Runners with PFP exhibit greater peak patella cartilage stress during running compared with pain-free individuals. The combination of knee external rotation and a high knee extensor moment best predicted the elevated peak stress during running.
本研究的主要目的是确定与无痛跑步者相比，患有髌股疼痛（PFP）的业余跑步者是否表现出更大的髌骨软骨峰值应力。次要目的是确定跑步过程中髌骨软骨峰值应力的运动学和/或动力学预测因素。共有22名女性业余跑步者（12名患有PFP，10名无痛对照者）参与了本研究。使用特定于个体的有限元模型对跑步支撑阶段最大膝关节屈曲角度进行模拟，从而量化髌骨软骨应力分布。有限元模型的输入参数包括特定于个体的髌股关节几何形状、股四头肌力量以及额面和横断面的下肢运动学。通过逐步回归分析对胫股关节运动学和动力学进行量化，以确定应力的最佳预测因素。与无痛跑步者相比，患有PFP的跑步者表现出更大的峰值静水压力（PFP组与对照组：21.2[5.6]MPa对16.5[4.6]MPa）和最大剪应力（PFP组与对照组：11.3[4.6]MPa对8.7[2.3]MPa）。膝关节外旋是峰值静水压力和峰值最大剪应力的最佳预测因素（分别占方差的38%和25%），其次是膝关节伸肌力矩（分别占方差的21%和25%）。与无痛个体相比，患有PFP的跑步者在跑步过程中表现出更大的髌骨软骨峰值应力。膝关节外旋和高膝关节伸肌力矩的组合最能预测跑步过程中升高的峰值应力。
