Surgical approaches to the capitellum: a comparative anatomic study

Abstract

Osteochondritis dissecans (OCD) of the humeral capitellum is an important cause of elbow disability in young athletes. Large and unstable lesions sometimes require joint reconstruction with osteochondral autograft. Several approaches have been described to expose the capitellum for the purpose of treating OCD. The posterior anconeus-splitting approach and the lateral approach with or without release of the lateral ligamentous complex are the most frequently used for this indication. The surface accessible by these approaches has not been widely studied. This study compared the extent of the articular surface of the capitellum that could be exposed with the Kocher approach (without ligament release) vs. the posterior anconeus-splitting approach. A secondary outcome was the measurement of any additional area that could be reached with lateral ulnar collateral ligament release (Wrightington approach). The 3 approaches were performed on 8 adult cadaveric elbows: first, the Kocher approach; then, the anconeus-splitting approach; and finally, the Wrightington approach. The visible articular surface was marked out after completion of each approach. The mean articular surface of the capitellum was 708 mm2 (range, 573-830 mm2). The mean visible articular surface was 49% (range, 43%-60%) of the total surface with the Kocher approach, 74% (range, 61%-90%) with the posterior anconeus-splitting approach, and 93% (range, 91%-97%) with the Wrightington approach. Although the Kocher approach provided access to the anterior part of the capitellum, the anconeus-splitting approach showed adequate exposure to the posterior three-quarters of the articular surface and overlapped the most posterior part of the Kocher approach. A combination of the 2 lateral ulnar collateral ligament-preserving approaches allowed access to 100% of the joint surface. Most OCD lesions are located in the posterior area of the capitellum and can therefore be reached with the anconeus-splitting approach. When OCD lesions are located anteriorly, the Kocher approach without ligament release is efficient. A combination of these 2 approaches enabled the entirety of the joint surface to be viewed.