[Impingement syndrome of the subacromial area: analysis of 42 cases].
To create a new classification of subacromial impingement phenomena according to different etiology, we treated 42 cases of impingement syndrome. They were 29 male, and 23 females, with an average age of 45 years. 29 patients had typical subacromial pain are signs. Positive impingement test was found in 30 patients. Roentgenographic findings showed that the high density of the great tuberosity (GT) in 27 cases, 8 cases got the cystic changes around the CT, and exostosis formed on the G. T. in 3 cases. The abnormal acromion with sloped or over hanging form was found in 6 cases. 11 cases had an irregular inferior surface of the acromion in two cases with the spur formed at inferior surface of acromion. Four patients combined with calcium deposit at subacromial space. Space narrowing of the AH interval was in noted 12 cases. According to the X-ray findings, 35 cases were classified into the abnormal anatomy structure group. The other 7 patients were in dynamic impingement group. 13 cases of impingement syndrome combined with the complication of rotator cuff tear were treated by the Mclaughlin's procedure for repairing the rotator cuff with the acromion plasty. 11 patients were followed up for more than 6 months after operation. 7 cases had excellent results and 4 cases good results. This classification includes two kinds of impingement syndromes: anatomical of structural and dynamic or dysfunction.