Carpenter J E, Blasier R B, Pellizzon G G
Orthopaedic Research Laboratories, MedSport, Section of Orthopaedic Surgery, University of Michigan, Ann Arbor 48106-0363, USA.
Am J Sports Med. 1998 Mar-Apr;26(2):262-5. doi: 10.1177/03635465980260021701.
Proprioception, or joint position sense, probably plays an important role in shoulder joint function. In this study, we assessed the effect of muscle fatigue on shoulder proprioception in 20 volunteers with no shoulder abnormalities. Shoulder proprioception was measured as the threshold to first detection of humeral rotation with the joint at 90 degrees of abduction and 90 degrees of external rotation. Subjects were tested while rested, exercised on a isokinetic testing machine until fatigued, and then retested in an identical fashion. Both shoulders were tested, and the order of dominant and nondominant shoulder was randomized. Shoulder proprioception was analyzed for its dependence on arm dominance, direction of rotation, and muscle fatigue. Subjects detected external rotation after significantly less movement than they did internal rotation. Overall, before exercise, motion was detected after a mean of 0.92 degrees of rotation. After exercise, this threshold to detection of movement increased to 1.59 degrees, an increase of 73%. This significant increase occurred with both internal and external rotation. The decrease in proprioceptive sense with muscle fatigue may play a role in decreasing athletic performance and in fatigue-related shoulder dysfunction. It remains to be determined if training can lessen this loss in position sense.
本体感觉，即关节位置觉，可能在肩关节功能中发挥重要作用。在本研究中，我们评估了肌肉疲劳对20名无肩部异常的志愿者肩部本体感觉的影响。肩部本体感觉通过在肩关节外展90度和外旋90度时首次检测到肱骨旋转的阈值来衡量。受试者在休息时接受测试，在等速测试机上运动直至疲劳，然后以相同方式再次测试。对双侧肩部进行测试，优势肩和非优势肩的测试顺序随机。分析肩部本体感觉对手臂优势、旋转方向和肌肉疲劳的依赖性。与内旋相比，受试者检测到外旋所需的运动量明显更少。总体而言，运动前，平均旋转0.92度后可检测到运动。运动后，检测运动的阈值增加到1.59度，增加了73%。内旋和外旋时均出现了这一显著增加。肌肉疲劳导致的本体感觉下降可能在运动表现下降和与疲劳相关的肩部功能障碍中起作用。训练是否能减轻这种位置觉丧失还有待确定。
