Arthroscopic Bankart suture repair for traumatic anterior shoulder instability: analysis of the causes of a recurrence.

Eighty-two patients with traumatic anterior shoulder instability were treated with an arthroscopic transglenoid multiple suture technique (Caspari's method) and followed-up for more than 2 years. A retrospective analysis of the clinical outcome was performed to determine the factors related to poor results. The mean age at operation was 21 years (range, 13 to 50 years) and the mean follow-up period was 40 months (range, 24 to 70 months). According to the status of the ligament-labrum complex and the glenoid bone defect, the Bankart lesions were classified into five types arthroscopically. There were 21 shoulders of type 1, 33 shoulders of type 2, 22 shoulders of type 3, and 6 shoulders of type 5. Twenty-four of the patients played contact sports before the operation. The clinical outcome was assessed by Rowe's criteria (1978). To analyze the factors related to a poor outcome, a multivariate analysis was done to assess the influence of 12 clinical factors (age at operation, age at first dislocation, sex, dominant side, disease duration, number of dislocations, sporting activity before operation, inferior joint laxity, thickness of the ligament-labrum complex, type of Bankart lesion, number of sutures, and method of suture fixation). Fifty-five of 82 patients had an excellent outcome, 14 had a good result, and 13 had a poor result. According to postoperative instability, redislocation was seen in 13 patients (16%), resubluxation in 2 patients (2%), with a recurrence rate of 18%. The mean limitation of external rotation at 90 degrees abduction was 6.0 degrees (range, 0 degrees to 30 degrees), and there was a 10 degrees loss of external rotation in 10 patients. The factors significantly related to recurrence were a type 3 Bankart lesion, playing contact sports preoperatively, a thin ligament-labrum complex, and repair with less than four sutures. In conclusion, a 18% rate of recurrence is not acceptable. To obtain a better clinical outcome, very careful selection of patients for this technique is necessary. Our analysis of the factors related to a poor outcome may help to decide what the proper indications are for this technique.