A case report of chronic posterior shoulder dislocation complicated with the incarcerated rotator cuff and the malunion of the greater tuberosity on the bicipital groove

There have been no reports of combined humeral greater tuberosity fracture malunion and intra-articular incarceration of the rotator cuff. A 19-year-old man presented to the emergency department with multiple traumatic injuries. He was diagnosed with a fracture of the greater tuberosity of the humerus and a brachial nerve injury. The patient was managed conservatively; however, his external rotational muscle strength did not improve. Eight months post-injury, magnetic resonance imaging was performed and a diagnosis of combined malunion of the greater tuberosity and incarceration of the rotator cuff was made. Open reduction, disincarceration, and internal fixation were performed, and the patient showed good progress. Extremely rare conditions including combined malunion of a greater tuberosity fracture and incarceration of the rotator cuff muscles are caused by posterior shoulder dislocations. These conditions can be successfully treated by open reduction, disincarceration, and internal fixation.