Department of Physical Education, National Defense Academy, yokosuka, Japan.
Scand J Med Sci Sports. 2018 Jan;28(1):196-202. doi: 10.1111/sms.12894. Epub 2017 May 2.
This study aimed to investigate the effect of surgery on the gamma loop of the quadriceps on the side with an intact knee in patients with anterior cruciate ligament (ACL) injuries. We compared longitudinally the response of alpha motor neurons to vibration stimulation of the quadriceps on the side with an intact knee before and after ACL reconstruction. To evaluate alpha motor neuron response, we measured the maximal knee extension strength and integrated electromyography of the vastus medialis, vastus lateralis, and rectus femoris. After obtaining pre-vibration data from each subject, vibration stimulation was applied to the infrapatellar tendon, and the same measurements were performed immediately after stimulation. The results of this study showed that the response to prolonged vibration stimulation on the intact side of the quadriceps did not differ pre- and post-surgery. As vibration stimuli normally elicit a decrease in alpha motor neuron activity in normal individuals, abnormal responses to prolonged vibration stimulation of the quadriceps on the side with an intact knee might be observed in patients with ACL injuries. The abnormality of the gamma loop of the quadriceps on the side with an intact knee was probably induced by the rupture. Based on these results, we conclude that surgery does not induce further gamma loop abnormalities on the intact side of the quadriceps.
本研究旨在探讨前交叉韧带（ACL）损伤患者膝关节健全侧股四头肌γ环在手术中的变化。我们对 ACL 重建前后膝关节健全侧股四头肌接受振动刺激时的α运动神经元反应进行了纵向比较。为了评估α运动神经元的反应，我们测量了最大膝关节伸展力和股直肌、股外侧肌和股内侧肌的整合肌电图。在从每位受试者获得预振动数据后，将振动刺激施加到髌下肌腱，并在刺激后立即进行相同的测量。研究结果表明，膝关节健全侧股四头肌在术前和术后接受长时间振动刺激的反应没有差异。由于振动刺激通常会在正常个体中引起α运动神经元活动的减少，因此在 ACL 损伤患者中，可能会观察到膝关节健全侧股四头肌接受长时间振动刺激时的异常反应。膝关节健全侧股四头肌γ环的异常可能是由于破裂引起的。基于这些结果，我们得出结论，手术不会导致膝关节健全侧股四头肌γ环进一步出现异常。
