Article

Muscle imbalance between serratus anterior (SA), upper trapezius
(UA), middle trapezius (MT), and lower trapezius (LT) muscles has been observed
in subjects with subacromial impingement syndrome (SAIS). OBJECTIVE: (1) To
investigate the effect of electromyography (EMG) biofeedback training on muscle
balance ratios and scapular kinematics in healthy adults and subjects with SAIS.
(2) To investigate whether the effects of EMG biofeedback on muscle balance
ratios are different between groups. DESIGN: Twelve healthy adults and 13
subjects with SAIS were recruited in this study. EMG was used to record the
activity of scapular muscles. The ratios (UT/SA, UT/MT, and UT/LT) during
exercises with/without EMG biofeedback were calculated. Scapular kinematics were
recorded before and after exercises with/without EMG biofeedback. RESULTS: For
the subjects with SAIS, muscle balance ratios were lower during forward flexion
with EMG biofeedback than during exercise only (UT/SA: 70.3-45.2; UT/LT:
124.8-94.6). Additionally, similar results were found during side-lying external
rotation (UT/MT: 58.5-36.4). For the scapular upward rotation and tipping in both
groups, there were no significant differences with and without EMG biofeedback.
CONCLUSION: EMG biofeedback improved the scapular muscular balance during
training exercises in both groups. Further clinical trials should investigate the
long-term effects of EMG biofeedback.
CI - Copyright (c) 2012 Elsevier Ltd. All rights reserved.

Langue : ANGLAIS