Faculty of Kinesiology, University of Calgary, Calgary, AB,Canada.
Biomechanics Laboratory, School of Sports, Federal University of Santa Catarina, Florianopolis, SC,Brazil.
J Appl Biomech. 2022 Jul 1;38(4):237-245. doi: 10.1123/jab.2021-0112. Print 2022 Aug 1.
The purpose of this study was to quantify the contribution of the individual quadriceps muscles to patellar tracking. The individual and/or combined quadriceps muscles were activated in rabbits (n = 6) during computer-controlled flexion/extension of the knee. Three-dimensional patellar tracking was measured for the vastus lateralis, vastus medialis, and rectus femoris when activated alone and when activated simultaneously at different frequencies, producing a range of knee extensor torques. Patellar tracking changed substantially as a function of knee extensor torque and differed between muscles. Specifically, when all quadriceps muscles were activated simultaneously, the patella shifted more medially and proximally and rotated and tilted more medially compared with when vastus lateralis and rectus femoris were activated alone (P < .05), whereas vastus medialis activation alone produced a similar tracking pattern to that observed when all quadriceps muscles were activated simultaneously. Furthermore, patellar tracking for a given muscle condition shifted more medially and proximally and rotated and tilted more medially with increasing knee extensor torques across the entire range of knee joint angles. The authors conclude that patellar tracking depends crucially on knee extensor force/torque and that vastus medialis affects patellar tracking in a distinctly different way than vastus lateralis and rectus femoris, which produce similar tracking patterns.
本研究的目的是量化股四头肌各肌肉对髌骨轨迹的贡献。在计算机控制的兔膝关节屈伸过程中（n = 6），激活各个和/或联合的股四头肌。当单独激活和以不同频率同时激活时，测量股外侧肌、股内侧肌和股直肌的三维髌骨轨迹，产生一系列膝关节伸肌扭矩。髌骨轨迹随膝关节伸肌扭矩的变化而显著变化，且在不同肌肉之间存在差异。具体来说，当所有股四头肌同时激活时，与单独激活股外侧肌和股直肌时相比，髌骨更向内侧和更向近端移位，并且更向内侧旋转和倾斜（P <.05），而单独激活股内侧肌则产生与同时激活所有股四头肌时相似的跟踪模式。此外，对于给定的肌肉状态，随着整个膝关节角度范围内膝关节伸肌扭矩的增加，髌骨轨迹更向内侧和更向近端移位，并且更向内侧旋转和倾斜。作者得出结论，髌骨轨迹严重依赖于膝关节伸肌力/扭矩，股内侧肌对髌骨轨迹的影响与股外侧肌和股直肌明显不同，后者产生相似的跟踪模式。
