Fracture of the anteromedial facet of the coronoid process. Surgical technique.

BACKGROUND: Fracture of the anteromedial facet of the coronoid was recently recognized as a distinct type of coronoid fracture resulting from a varus posteromedial rotational injury force. Very few reports are available to help guide the management of these injuries.
METHODS: Eighteen patients with a fracture of the anteromedial facet of the coronoid process were treated over a six-year period. Twelve patients were treated for the acute fracture, and six were managed after initial treatment elsewhere. All but three patients (two with concomitant fracture of the olecranon and one with a second fracture at the base of the coronoid) had avulsion of the origin of the lateral collateral ligament complex from the lateral epicondyle. The initial treatment was operative in fifteen patients and nonoperative in three. The coronoid fracture was secured with a plate applied to the medial surface of the coronoid in nine patients, a screw in one patient, and sutures in one patient. It was not repaired in the remaining seven patients.
RESULTS: At the final evaluation, an average of twenty-six months after the injury, six patients had malalignment of the anteromedial facet of the coronoid with varus subluxation of the elbow, which was due to the fact that the fracture had not been specifically treated in four patients and to loss of fracture fixation in two patients. All six had development of arthrosis and a fair or poor result according to the system of Broberg and Morrey. The remaining twelve patients had good or excellent elbow function.
CONCLUSIONS: Anteromedial fractures of the coronoid are associated with either subluxation or complete dislocation of the elbow in most patients. Secure fixation of the coronoid fracture usually restores good elbow function.