EFFECT OF POSITION AND CHANGE OF ANGLE ON ACTIVITY OF SHOULDER MUSCLES DURING SCAPULAR PLANE ABDUCTION
- VernacularTitle:肩外転運動時の運動肢位と角度変化が肩周囲筋の活動様相に及ぼす影響
- Author:
TAKASHI YASOJIMA
;
TOMOHIRO KIZUKA
;
HIROSHI NOGUCHI
;
HITOSHI SHIRAKI
;
NAOKI MUKAI
;
YUTAKA MIYANAGA
- Publication Type:Journal Article
- Keywords:
EMG;
shoulder;
scapular plane abduction;
full can;
empty can
- From:Japanese Journal of Physical Fitness and Sports Medicine
2003;52(5):491-498
- CountryJapan
- Language:Japanese
-
Abstract:
The purpose of this study is to identify the effect of position (full can, empty can) and change of angle on the activity of shoulder muscles during scapular plane abduction ; and also to examine its application to exercises used for rehabilitation of shoulder muscles. Seven healthy subjects (23.4±1.4 yr) with normal shoulder function performed scapular plane abduction with external rotation (full can) and scapular plane abduction with internal rotation (empty can) . An electromyogram was recorded with a fine wire intramuscular electrode at the supraspinatus, deltoid anterior, middle, posterior and trapezius upper with bipolar surface. The EMG activity (RMS) of each muscle was normalized by the highest EMG activity (100%RMS) during a maximum manual muscle test for each muscle (%RMS) . The %RMS of each muscle remarkably increased with a change of the angle for empty can, whereas it showed a slight increase with a change of the angle for full can. This finding suggests that the position of full can and empty can in scapular plane abduction affects the function of shoulder muscles. In addition, full can exercise is recommended in order to improve function of the supraspinatus and the muscular activity balance between the supraspinatus and the deltoid. Empty can exercise is applied to sport-specific exercise for rehabilitation of shoulder muscles.
