Kelley J D, Lombardo S J, Pink M, Perry J, Giangarra C E
Centinela Hospital Medical Center, Biomechanics Laboratory, Inglewood, California 90301.
Am J Sports Med. 1994 May-Jun;22(3):359-63. doi: 10.1177/036354659402200311.
Lateral epicondylitis occurs frequently in tennis players and appears to be caused by tears in the extensor aponeurosis. The purpose of this study was to compare the electromyographic activities of 5 muscles in players with lateral epicondylitis with those of injury-free players during the single-handed backhand tennis stroke. Finewire electrodes were placed into the extensor digitorum communis, extensor carpi radialis longus and brevis, pronator teres, and flexor carpi radialis muscles in competitive tennis players; 8 players had lateral epicondylitis and 14 had normal upper extremities. The backhand stroke then was recorded on high-speed film and synchronized with the electromyographic signal. The injured players had significantly greater activity for the wrist extensors and pronator teres muscles during ball impact and early follow-through. This activity increase may have been caused by the abnormal mechanics evident on film, including a "leading elbow," wrist extension and an open racquet face near the time of ball impact, and ball contact in the lower half of the strings. These mechanics not only result in a lower level of play but also leave the wrist extensors and the pronator teres muscles vulnerable to injury. This is the first study that documents increased activity in muscles that have been previously injured.
外侧上髁炎在网球运动员中频繁出现，似乎是由伸肌腱膜撕裂引起的。本研究的目的是比较患有外侧上髁炎的运动员与无损伤运动员在单手反手网球击球过程中5块肌肉的肌电活动。将细丝电极置于竞技网球运动员的指总伸肌、桡侧腕长伸肌和桡侧腕短伸肌、旋前圆肌和桡侧腕屈肌中；8名运动员患有外侧上髁炎，14名运动员上肢正常。然后用高速胶片记录反手击球动作，并与肌电信号同步。受伤运动员在球撞击和早期随挥阶段，腕伸肌和旋前圆肌的活动明显更大。这种活动增加可能是由胶片上明显的异常力学引起的，包括“领先的肘部”、腕部伸展以及在球撞击时球拍面打开，球接触球拍弦的下半部分。这些力学不仅导致击球水平降低，还使腕伸肌和旋前圆肌容易受伤。这是第一项记录先前受伤肌肉活动增加的研究。
