Articular shear injuries of the capitellum in adolescents

Background Fractures of the capitellum are rare and are commonly classified into 4 types. Type II variants involve a shear injury with a mostly articular cartilage component and little subchondral bone. Symptoms upon presentation after these injuries are variable, and the diagnosis can be difficult to make in the immature skeleton. Methods We retrospectively reviewed 3 cases of type II capitellar fractures in adolescent athletes who presented for evaluation with the senior author. Results All patients were initially treated conservatively, without identification or treatment of the capitellar shear component of their injury. Unfortunately, radiocapitellar arthrosis rapidly developed in all 3 and required surgical intervention at our institution. At an average postoperative follow-up of 49 months from the index procedure, patients ultimately had positive outcomes despite advanced degenerative changes on imaging. One patient required 2 subsequent operations for mechanical symptoms and pain. Discussion The 3 reported cases represent adolescent, athletic patients with missed shear injuries to the capitellum. These patients exhibited low Disabilities of Arm, Shoulder and Hand scores and high Mayo Elbow Performance Scores at final follow-up, but each patient demonstrated advanced degenerative changes on imaging, and 1 patient required 2 subsequent operations for mechanical symptoms and pain. A high index of suspicion is necessary to identify this injury pattern, and proper plain radiographic imaging with a low threshold for advanced imaging is necessary. Although the overall long-term prognosis is unknown for these patients, early recognition likely would have changed the initial conservative management decision in each and, theoretically, might have altered the outcome for these patients.