Intraarticular lesions in primary frozen shoulder after manipulation under general anesthesia

The aim of this study was to find intraarticular lesions after manipulation under general anesthesia in patients with primary frozen shoulder. In a prospective trial conducted between 2001 and 2003 in 30 patients with primary frozen shoulder, the affected shoulders were manipulated while the patients were under general anesthetia. Exclusion criteria were secondary stiffness caused by rotator cuff tears and glenohumeral arthritis. After manipulation, each patient was examined by arthroscopy, and any intraarticular lesions were documented. In all patients, during manipulation, a significant improvement in the range of motion was achieved. Under anesthesia, flexion improved on average from 70 degrees +/- 33 degrees to 180 degrees +/- 15 degrees, abduction from 50 degrees +/- 20 degrees to 170 degrees +/- 25 degrees, and external rotation from -5 degrees +/- 10 degrees to +40 degrees +/- 20 degrees. Arthroscopy revealed hemarthrosis in all patients after manipulation. In 22 patients, localized synovitis was detected in the area of the rotator interval, whereas in 8 patients, disseminated synovitis was observed as a feature of adhesive capsulitis. After manipulation, the capsule was seen to be ruptured superiorly in 11 patients, the anterior capsule was ruptured up to the infraglenoid pole in 24 patients, and 16 patients each had a capsular lesion located posteriorly. In 18 patients no additional joint damage was found after manipulation. In 4 patients, iatrogenic superior labrum anterior-posterior lesions were observed. Further injuries detected were 3 fresh partial tears of the subscapularis tendon, 4 anterior labral detachments (1 with a small osteochondral defect), and 2 tears of the middle glenohumeral ligament. Even though manipulation under anesthesia is effective in terms of joint mobilization, the method can cause iatrogenic intraarticular damage.