Surgical management of posterior shoulder instability

Posterior shoulder instability is a rare entity and accounts for 2-10 % of all shoulder instabilities. Diagnosing and managing of this pathology can be challenging due to unspecific symptoms reported by the patient. Thus a meticulous clinical exam of both shoulders is mandatory. Posterior instability can be caused by dysplasia of the posterior chondrolabral rim, bony glenoid retroversion or increased volume of the posteroinferior capsular pouch. To provide adequate therapy it is essential to understand the complexity of this pathology and its etiology, such as single traumatic events, repeated microtraumata or atraumatic causes. Each therapeutic approach should be started with physical therapy including muscle strengthening and proprioception. If this fails arthroscopic posterior stabilization is suggested for patients with isolated labral repair. In patients with failed arthroscopic management or higher grades of posterior laxity open stabilization should be favored. Patients with significant bone loss or glenoid retroversion benefit from open procedures like glenoid osteotomy or bone blocks. Considering defined therapeutic algorithm in combination with intensive physical therapy lead to good postoperative function with very low instability recurrence rates.