Normal Glenohumeral and Scapulothoracic Movement at the Coronal Plane |
Yong Girl Rhee, Chang Moo Yim |
Dept. of Orthopedic Surgery, School of Medicine, Kyung Hee University |
정상인의 관상면에서의 관절와상완운동 및 견갑흉곽운동 |
이용걸, 임창무 |
경희대학교 의과대학 정형외과학교실 |
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Abstract |
We measured the glenohumeral and scapulothoracic movements during abduction of the arm in the coronal plane with radiologic analysis in the 30 shoulders of normal male adults who were without pain, limitation of motion, and history of trauma. In the resting position, the glenoid cavity of the scapula faced somewhat superiorly in over 80 percents of the individuals, the mean superior tilting was 5.7 degrees. The mean total scapulothoracic movement was 65.8 degrees and the mean total glenohumeral movement was 106.8 degrees during abduction of arm in the coronal plane. The mean ratio of the glenohumeral movement to the scapulothoracic movement was 1.6 and this GH/ST ratio was decreased toward the extreme abduction. When the arm was abducted, external rotation of the humeral head occurred and this external rotation was increased smoothly during 0 degree through 90 degrees, but steeply above 90 degrees. The acromiohumeral interval was 10.9 mm at the resting positon, and this interval decreased during the arm abduction. The superior migration of the humeral head was 3.1 mm while abducting the arm. Our measurement of the relationships of glenohumeral and scapulothoracic movements at the coronal plane would be useful in the understandings of the biomechanics of shoulder, but further study would be required for the analysis of the three dimensional relationship because of the limitation of our two dimensional analysis. |
Key Words:
Shoulder; Movement; Glenohumeral and scapulothoracic |
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