肩峰下夾擠症候群病患接受運動結合肌電回饋訓練之立即療效: 肌肉活動特性及肩胛骨運動學

Abstract

背景：臨床上針對肩關節疾病的患者，發現其肩胛骨在動作過程中會產生動作不能的情形，及在動作過程中前鋸肌、上斜方肌及下斜方肌肌肉控制不平衡的現象發生，特別是肩夾擠症候群患者。文獻指出，這種現象可能會造成肩關節動作的改變進而造成更進一步的傷害，因此針對有動態肌肉控制不能及動作不能的患者，臨床上以肌力訓練其肌肉及動作控制，一般相信肌電回饋治療配合運動治療計畫有加乘的療效。目的：本實驗之目的以健康人及患有肩夾擠症候群患者為研究對象探討 (1)運動結合肌電回饋是否能改變在各種運動治療中肌肉控制 (2)健康人及肩夾擠症候群患者對於運動結合肌電回饋對於肌肉控制之效果是否不同 (3)運動結合肌電回饋對於肩胛骨運動學的立即效果。實驗設計:以12位健康成人及13位有肩夾擠症候群患者為研究對象，使用運動結合肌電回饋儀訓練及運動訓練，檢視其肌電圖之肌肉平衡比率。並在兩種訓練前後，測量在肩胛骨平面抬手動作的肩胛骨關節動作。主要測量:運動中及運動中結合肌電回饋時肌肉的平衡比率(上斜方肌/下斜方肌、上斜方肌/中斜方肌及上斜方肌/前鋸肌)及兩種訓練前後之肩胛骨運動學（肩胛骨上/下轉及前/後傾）。實驗結果:結果顯示患有肩夾擠症候群患者在執行上舉運動結合肌電回饋訓練能有效降低肌肉平衡比率(上斜方肌/前鉅肌:70.3- 45.2; 上斜方肌/下斜方肌: 124.8- 94.6)。而患者在側躺肩外轉運動結合肌電回饋訓練也能達到降低肌肉平衡比率的效果(上斜方肌 /中斜方肌:58.5- 36.4)。而在兩種訓練前後的肩胛骨運動學，無論是在肩胛骨上轉及前傾並無差異。結論:根據結果，兩組受試者在上舉及側躺肩外轉這兩種運動下結合肌電回饋訓練皆能達到降低肌肉平衡比率的立即效果。肌力訓練運動訓練結合肌電回饋可以使肌肉平衡比率下降，然而肌電回饋之短期及長期療效仍有待未來更 一步的研究。

Background: Muscle imbalance between searratus anterior and trapezius muscles as well as scapular dyskinesis have been observed in subjects with shoulder disorder such as impingement syndrome. Previous studies indicate that the muscle imbalance of scapular muscle can result in abnormal scapular motion and may contribute to further damage of impingement. In clinics, physical therapists usually use strengthening exercises to restore proper scapular muscle balance and motor control in patients with subacromial impingement syndrome (SAIS). Electromyography (EMG) biofeedback technique is believed to allow subjects to learn how to control the activities of stabilizers/force couples and to enhance motor program training. Objective: The purposes of this study are (1) to investigate the effect of EMG biofeedback training on muscle balance ratios during exercises in healthy adults and subjects with SAIS; (2) to investigate whether the effects of EMG biofeedback on muscle balance ratios are different between healthy adults and subjects with SAIS (3) to investigate the immediate effect of EMG biofeedback training on scapular kinematics in healthy adults and subjects with SAIS. Design: Twelve healthy adults and thirteen subjects with SAIS were recruited in this study. 3-D electromagnetic motion analysis and EMG muscle activity were used to record the scapular kinematics and muscle balance ratios during exercises with and without EMG biofeedback. The scapular kinematics were also recorded before and after exercises with/without EMG biofeedback. Main outcome measures: The balance ratios (UT/LT, UT/MT and UT/SA) and scapular kinematics (scapular upward/downward rotation, anterior/posterior tipping) were outcomes of this study. Result: For the subjects with SAIS, the lower muscle balance ratios were found when the subjects performed the forward flexion exercises with EMG biofeedback than exercise only (UT/SA: 70.3- 45.2; UT/LT: 124.8- 94.6). Additionally, the similar results were found in the side-lying external rotation (UT/MT: 58.5- 36.4). For the kinematics, there were non-significant differences between exercise and exercise with biofeedback in change scores of upward rotation and tipping angle in both groups. Conclusion: Results illustrated the potential of EMG biofeedback for restoring the scapular muscular balance during the forward flexion and side-lying external rotation exercises in both groups. Based on our results, we suggest the use of EMG biofeedback combined with the strengthening exercise to promote the scapular muscle balance. Further clinical trial should investigate the short-term and long-term effects of EMG biofeedback.