Glousman R E, Barron J, Jobe F W, Perry J, Pink M
Kerlan-Jobe Orthopaedic Clinic, Inglewood, California.
Am J Sports Med. 1992 May-Jun;20(3):311-7. doi: 10.1177/036354659202000313.
Electromyography and high-speed film were used to examine the muscle activity in the elbows of pitchers with medial collateral ligament insufficiency compared to the activity in uninjured elbows. Ten competitive baseball pitchers with medial collateral insufficiency and 30 uninjured competitive pitchers were tested while throwing the fastball and the curveball. The extensor carpi radialis brevis and longus in the injured pitchers showed greater activity than in the uninjured pitchers for both pitches. The triceps, flexor carpi radialis, and pronator teres all showed less activity in the injured pitchers during the fastball, but only the triceps had less activity during the curveball. The differences were seen during the late cocking and acceleration phases, which place the greatest stress on the medial collateral ligament. If the flexor carpi radialis and pronator teres were substituting for the deficient medial collateral ligament and functioning as dynamic stabilizers, one would expect enhanced muscle activity. However, the opposite was found. This pattern of asynchronous muscle action with medial collateral ligament injury may predispose the joint to further injury. The muscular differences seen are critical to the understanding of the pathomechanics of patients with medial collateral ligament deficiency, and provide a basis for rehabilitation.
与未受伤肘部的肌肉活动相比，肌电图和高速胶片被用于检查内侧副韧带不足的投手肘部的肌肉活动。对10名内侧副韧带不足的职业棒球投手和30名未受伤的职业投手在投快速球和曲线球时进行了测试。在两种投球动作中，受伤投手中的桡侧腕短伸肌和桡侧腕长伸肌的活动都比未受伤投手的更强烈。在投快速球时，受伤投手中的肱三头肌、桡侧腕屈肌和旋前圆肌的活动都较少，但在投曲线球时只有肱三头肌的活动较少。这些差异出现在后摆晚期和加速阶段，这两个阶段对内侧副韧带施加的压力最大。如果桡侧腕屈肌和旋前圆肌在替代不足的内侧副韧带并起到动态稳定器的作用，人们会预期肌肉活动增强。然而，结果却相反。内侧副韧带损伤时这种异步肌肉动作模式可能使关节更容易进一步受伤。观察到的肌肉差异对于理解内侧副韧带不足患者的病理力学至关重要，并为康复提供了依据。
