[Posterosuperior impingement of the shoulder in the athlete: results of arthroscopic debridement in 75 patients].

PURPOSE OF THE STUDY

The painful shoulder is a well-recognized clinical entity in throwers although the pathogenic mechanisms involved are still debated. In 1991 Walch then Jobe developed the concept of posterosuperior impingement to explain lesions observed arthroscopically. This impingement between the deep aspect of the supraspinatus tendon and the glenoid occurs during loaded arm movements. The purpose of this work was to study the different types of lesions observed arthroscopically and to analyse outcome after arthroscopic debridement.

MATERIAL AND METHOD

Our series included 75 thrower athletes who had shoulder pain for loaded arm movements. Pain was situated in the dominant shoulder in all cases. Clinically, the Jobe manipulation provoked pain in 52 patents, expression of a supraspinous disorder. After failure of conservative treatment, the patients underwent arthroscopy for assessment and debridement. At the time of arthroscopy, the patients had suffered pain for two years (mean 22.3 months). All 75 patients were seen for clinical and radiological assessment at least two years after arthroscopy.

RESULTS

Among the 75 arthroscopies, there were 67 (89%) partial tears involving the deep aspect of the cuff, associated in 90% of the cases with a labral lesion. Tears involved the supraspinatus in 40 cases, the supraspinatus and the infraspinatus in 24 and the infraspinatus alone in three. Eight patients were free of tendon lesions at arthroscopy. There were no full thickness tears. The labrum had a meniscal (45%) or non-meniscal aspect (55%) and appeared normal (18%), fringed (38%) or fissured (52%). The very large majority of the labral fissures were found behind the biceps insertion. Fissures of the labrum were found in front of the biceps insertion in only three cases (slap lesion). Arthroscopy demonstrated glenoid damage (soft cartilage, fissure, abrasion, wear). The humeral head also exhibited lesions of the cartilage facing the insertion of the infraspinatus. At last follow-up (minimum > 2 years), eight patients were very satisfied, 22 were satisfied and 45 were disappointed. Twelve patients had resumed their sports activities at their former level with loaded arm movement and one patient had interrupted all sports activities. At last follow-up, 22 patient had undergone another surgical procedure: 20 derotation osteotomies of the humerus, one anterior stabilization, one acromioplasty.

DISCUSSION

The notion of posterosuperior impingement is increasingly recognized as the cause of pain in thrower athletes. Loaded arm movements produce a physiological contact between the posteriorsuperior edge of the glenoid cavity and the deep aspect of the rotator cuff. Injury results from repeated loaded arm movements in throwers. In our series, all the patients had at least one lesion, either involving the cuff or the labrum. According to the Snyder classification, 80% of the supraspinatus lesions were grade 1 or grade 2. We did not have any full thickness tears. All patients with a normal cuff were found to have a lesion of the posterosuperior labrum. At arthroscopy, dynamic assessment evidenced an impingement between the supraspinatus (or the infraspinatus) and the labrum or the bony edge of the glenoid cavity. Only three patients had a labral lesion anterior to the biceps insertion that could be considered a type 1 or 2 slap lesion. Unlike earlier reports by others, we had disappointing results after debridement: 60% of the patients were disappointed after the procedure and only 40% were satisfied (22 patients) or very satisfied (8 patients). Patient satisfaction depended greatly on the level of sports activity attained after arthroscopy, the eight very satisfied patients had resumed their former level. None of the professional athletes or those competing at the international level were very satisfied with arthroscopic debridement. There was an inverse relationship between level of competition and patient satisfaction after debridement.