Surgical treatment for avulsion injuries of the humeral lesser tuberosity apophysis in adolescents.

BACKGROUND There is little published information regarding avulsion fractures of the humeral lesser tuberosity in adolescents, and no consensus exists on optimal treatment. The purpose of this study was to investigate the demographics, injury mechanisms, and results of operative treatment of lesser tuberosity avulsion fractures in skeletally immature patients. METHODS Eight patients were treated with open reduction and internal fixation (ORIF) for lesser tuberosity avulsion fractures from 2000 through 2010. Data were collected regarding patient demographics, mechanisms of injury, operative findings, and early clinical results. Preoperative radiographic studies were evaluated, and patient-derived functional outcome scores were obtained. The mean age of the patients was 13.3 years. All patients were male and sustained sports-related injuries, typically from forceful shoulder abduction and external rotation with eccentric subscapularis load. The dominant extremity was injured in six patients. Six patients had initial radiographs that were interpreted as normal. Time from injury to surgery ranged from two weeks to five months. Surgical treatment consisted of ORIF with use of suture anchors (in six patients) or transosseous sutures (in two patients). RESULTS All patients achieved pain relief, and there were no neurovascular complications. All patients had full return of internal rotation strength, negative lift-off tests, and negative belly-press tests postoperatively. Average time to return to sports was 4.4 months postoperatively. Return of full external rotation occurred in five patients at an average of 4.9 months postoperatively. There were no refractures. Patient-derived functional outcomes scores at an average of 24.6 months after surgery demonstrated excellent shoulder function and high patient satisfaction. CONCLUSIONS Humeral lesser tuberosity avulsion fractures do occur in adolescents, typically from high-energy sports injuries. Careful physical examination and magnetic resonance imaging (MRI) evaluation aid in achieving a timely diagnosis. Surgical reduction and suture fixation is safe and effective in restoring subscapularis function and return to sports, even in cases of delayed treatment. Full recovery of shoulder external rotation may not be seen until six months postoperatively.