肩峰の傾斜の臨床計測と Subacromial impingement syndrome との関係

抄録

Based on the data presented in 1986, we tried to make a clinical application for measuring the slope of the acromion. First, we took a correct lateral view X-ray film of scapula through a fluoroscope by using macerated scapulae and named it as supraspinatus outlet view. This lateral view of the scapula must show a clear shape of supraspinatus fossa and spine of scapula. Then we measured the slope of the acromion (α-angle) with the procedure presented in 1986, and we confirmed the accuracy of the data obtained by this method. Next by using this procedure, we took 228supraspinatus outlet views of both 71 healthy males and 43 females, their age ranged from 18 to 33. Then we measured the slope of the acromion. The a-angle of healthy male was 33.6+4.3 degrees and that of healthy female was 35.0 ±4.3 degrees, ranged from 23 to 45 degrees. There was an apparent difference in a-angle between healthy males and females (p<0.02). Finally, we measured the a-angle of both 56 shoulders in 28 males and 16 shoulders in 8 females who had stage II subacromial impingement lesion without spur on the undersurface of the acromion. Their age ranged from 15 to 48. The a-angle was 30.5±3.4 degrees in males and 31.9±2.8 degrees in females, ranged from 23 to 39 degrees. The a-angle of the patient with impingement lesion was singnificantly less than that of healthy adult (p<0.001). The following results were obtained; Supraspinatus outlet view was clinically useful in measuring the slope of the acromion. The less or flat slope of the acromion may be an important factor in the pathogenesis of subacromial impingement.