[Arthroscopic treatment of posterior shoulder instability: technique and results]

Posterior shoulder instability occurs in approximately 2-5% of all cases of shoulder instability and treatment is still challenging. Open capsular plication procedures are described, but significant complications and risks have been reported in the literature. Arthroscopy has led to a better understanding of the pathoanatomy of posterior shoulder instability in recent years. We present our operative technique and the results of arthroscopic posterior shoulder stabilisation for the management of posterior shoulder instability. Sixteen patients with posterior shoulder instability were treated by arthroscopic posterior stabilisation from January 2004 to March 2005. There were 11 male and 5 female patients. The mean age was 24 (15-45) years. Nine patients had a unidirectional posterior instability. Seven patients had a predominantly posterior instability based on a multidirectional instability. Fourteen patients were evaluated after a mean follow-up of 12 (6-18) and 20 (14-26) months. Stability, range of motion and function were assessed using the Rowe score. The average Rowe score improved from pre-operative 32 (20-40) points to post-operative 87 (40-100) points after the first follow-up and 90 (40-100) points after the second follow-up. Furthermore subjective shoulder function was evaluated using a visual analog scale. The average score improved from pre-operative 3 (0-6) points to post-operative 8 (4-10) points after the first and second follow-up. At the first follow-up 93% of the patients had a stable shoulder; 85% had a stable shoulder after arthroscopic stabilisation at the second follow-up. Arthroscopic treatment for posterior shoulder instability is a demanding procedure. Due to a special operative technique with specific instruments soft tissue pathologies found in this type of instability such as capsular redundancy and labral tears can be addressed. Our results show that it can be used as an effective tool for the treatment of posterior shoulder instability.