The posterior locked shoulder dislocation is a rare injury that is often associated with an impression fracture of the anteromedial aspect of the humeral head. The majority of posterior shoulder dislocations are missed on the initial examination.We demonstrate the case of an athlete, who presented with a posterior shoulder dislocation after a trauma two months ago.The patient was treated with a M. subscapularis transfer in the reverse-hill-sachs-lesion.The diagnosis of the posterior shoulder dislocation remains a problem in the clinical setting. Treatment is based on the size defect of the anteromedial humeral head. Different treatment options are still controversially discussed.To diagnose a posterior shoulder dislocation correctly a standard clinical and radiological assessment is necessary.