Surgical Approaches To The Capitellum: A Comparative Anatomic Study.

BACKGROUND: Osteochondritis dissecans (OCD) of the humeral capitellum is an important cause of elbow disability in young athletes. Large and instable lesions sometimes require joint reconstruction with osteochondral autograft. Several approaches have been described to expose the capitellum for the purpose of treating an OCD. The posterior "anconeus-split" approach and the lateral approach with or without release of the lateral ligamentous complex are the most frequently used in 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) versus with the posterior "anconeus-splitting" approach. A secondary outcome was the measurement of any additional area that could be reached with lateral ulnar collateral ligament (LUCL) release (Wrightington approach).

METHODS: The three approaches were performed on eight 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.

RESULTS: 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 "anconeous split" approach and 93% (range 91%-97%) with the Wrightington approach. Although the Kocher approach provided access to the anterior part of the capitellum, the "anconeous split" 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 two LUCL preserving approaches allowed access to 100% of the joint surface.

CONCLUSION: Most OCD are located in the posterior area of the capitellum and can therefore be reached with the "anconeus splitting" approach. When OCD is located anteriorly, the Kocher approach without ligament release is efficient. A combination of these two approaches enabled the entirety of the joint surface to be viewed.