Examination of Intraoperative Arthroscopic Findings and Postoperative Results in Middle-aged to Elderly Patients in whom Rotator Interval Lesion was Suspected

Abstract

We performed arthroscopic surgery on 14 middle-aged to elderly patients in whom MRI did not reveal any tear of the rotator cuff, but arthrography showed the instant bulging of the contrast medium in the lateral area of the coracoid process, suggesting a rotator interval lesion. We investigated the intraoperative arthroscopic findings and postoperative results, with a postoperative follow-up of 6 months or more. The subjects consisted of 7 males and 7 females. Ages at the time of surgery ranged from 56.0 to 79.0 years old. In all patients, scapulohumeral arthroscopy revealed incomplete tear of the supraspinatus on the articular side and enlargement of the rotator interval. Tear of the subscapular is was observed in 9 shoulders. Tendon injury of the biceps long head was noted in 5 shoulders. Incomplete tear of the supraspinatus was repaired with trans-tendon repair. In 8 shoulders with tear of the subscapularis, interrupted suture with an anchor was selected for repair. In 1, debridement alone was performed. The mean range of shoulder motion for flexion, abduction, and external rotation before surgery was 155.0°, 152.9 °, and 46.4°, respectively. On the final survey, it was 158.6°, 156.4°, and 32.9°, respectively. The mean preoperative JOA scores for pain and total evaluation were 10.0 and 72.8 points, respectively. On the final survey, the scores were 26.8 and 91.1 points, respectively. Based on MRI findings on the final survey, 13 shoulders were classified as type 1 according to Sugaya's classification, and 1 as type 2. In middle-aged to elderly patients, tear of the supraspinous muscle tendon on the articular capsule side and tear in the superior region of the subscapular muscle tendon led to enlargement of the rotator interval. The short-term results of repair of the supraspinous and subscapular muscle tendons were favorable.