Multidirectional shoulder instability in young athletes

In 1980 Neer and Foster suggested the concept of multidirectional shoulder instability (MDI). The hallmark of this clinical condition is the presence of symptomatic inferior instability in addition to anterior and posterior instability. Although a redundant capsule was believed to be the main pathological lesion and the inferior capsular shift procedure had become the standard operation in the management of MDI that does not respond to non-operative treatment, the entire spectrum of MDI was not clearly identified. In 2002 Gerber and Nyffeler classified MDI into MDI with hyperlaxity and without hyperlaxity. The most commonly recommended treatment for MDI is exercise-based management; however, there is a need for high-quality intervention studies to be undertaken to validate the effects of exercise on MDI. In the studies of arthroscopic capsular plication procedures, failure rates (recurrent instability) were 18-21 % and return to preoperative level of sports was 86 %, which are comparable to the results of open capsular shift.