Technique Spotlight: ORIF Medial Coronoid Fracture

Indications

Indications for open reduction internal fixation of a medial coronoid fracture include a large medial coronoid fracture in the setting of an unstable elbow. Regan and Morrey described coronoid fractures based upon the lateral plain film radiographs ( Fig. 49.1 ), but the advent and widespread use of computed tomography (CT) scan with two- and three-dimensional reconstructions expanded our understanding of coronoid fracture anatomy and biomechanics ( Table 49.1 ; Fig. 49.2 ). We now know that the anteromedial facet of the coronoid is especially important to buttress and stabilize the elbow particularly against varus posteromedial rotatory forces. Varus posteromedial rotatory forces may act to avulse the lateral ulnar collateral ligament (LUCL) and impact the medial coronoid against the medial aspect of the trochlea, resulting in a fracture of the anteromedial coronoid. Large fragments include the sublime tubercle and, therefore, the medial collateral ligament (MCL) becomes incompetent. Surgical fixation for these large fragments is generally recommended to restore stability to the elbow, as unrecognized instability will lead to medial joint narrowing and wear, and rapid onset of arthrosis.