Classification, treatment, and outcome of osteochondritis dissecans of the humeral capitellum. Surgical technique.

BACKGROUND: Indications for the treatment of osteochondritis dissecans of the humeral capitellum have remained unclear. The aims of this study were to analyze the outcomes and to determine the most useful classification for the choice of treatment.

METHODS: The cases of 106 patients with osteochondritis dissecans of the capitellum were studied retrospectively. At the time of the initial presentation, the mean age of the patients was 15.3 years. The capitellar growth plate was open in eighteen patients and closed in eighty-eight. Thirty-six patients were treated nonoperatively. Fifty-five patients underwent fragment removal alone, twelve underwent fragment fixation with a bone graft, and three underwent reconstruction of the articular surface with use of osteochondral plug grafts from the lateral femoral condyle. The mean follow-up period was 7.2 years. The outcomes in terms of pain in the elbow, return to sports, and radiographic findings were analyzed and compared.

RESULTS: An osteochondritis dissecans lesion with an open capitellar physis and a good range of elbow motion resulted in a good outcome. Continued elbow stress resulted in the worst outcome in terms of pain and radiographic findings. In patients with a closed capitellar physis, surgery provided significantly better results than elbow rest (p < 0.01). Fragment fixation or reconstruction provided significantly better results than fragment removal alone (p < 0.05). The results of removal alone were dependent on the size of the defect in the capitellum. The outcome in terms of pain was closely associated with sports activity and radiographic findings.

CONCLUSIONS: We believe that osteochondritis dissecans of the capitellum can be classified as stable or unstable. Stable lesions that healed completely with elbow rest had all of the following findings at the time of the initial presentation: an open capitellar growth plate, localized flattening or radiolucency of the subchondral bone, and good elbow motion. Unstable lesions, for which surgery provided significantly better results, had one of the following findings: a capitellum with a closed growth plate, fragmentation, or restriction of elbow motion of >or=20 degrees . For large unstable lesions, fragment fixation or reconstruction of the articular surface leads to better results than simple excision.