Arthroscopically determined degree of injury after shoulder dislocation relates to recurrence rate.

Background: The glenohumeral joint is the most mobile articulation in the body and the most commonly dislocated diarthrodial joint with peaks in the incidence of dislocation occurring during the second and sixth decades. Age at the time of the initial dislocation is inversely related to the recurrence rate. Traumatic anterior instability is often associated with intraarticular injuries. The frequency of injuries may increase with dislocation or subluxation episodes.

Questions/purposes: We compared the frequency of lesions associated with traumatic anterior instability in patients with primary and recurrent instability.

Methods: We retrospectively reviewed 96 selected patients with traumatic anterior instability treated arthroscopically between 2005 and 2008. Forty-five had arthroscopy after a first episode of dislocation (Group I) and 51 had two or more episodes of instability (Group II). We compared the frequencies and percentage of intraarticular lesions in both groups.

Results: We observed a Bankart lesion in all patients of both groups. The posterior Bankart lesion was observed more frequently in Group II than in Group I: 47% versus 28%. SLAP lesions were observed in 12% in Group I and 24% in Group II. In 10 patients in Group II, there was an associated rotator cuff tear.

Conclusions: Patients with recurrent shoulder dislocation had a higher arthroscopic degree of injury. These patients presented more posterior labral lesions, SLAP tears, and rotator cuff pathology than patients with a first episode of shoulder dislocation.

Level Of Evidence: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.