Outcome of Asymptomatic Osteochondritis Dissecans of the Capitellum in Adolescent Baseball Players: A 2-year Follow-up Study

OBJECTIVES: Osteochondritis dissecans (OCD) of the capitellum is a well-recognized cause of elbow pain and disability in adolescent baseball players. OCD is classified into three different stages based on AP radiographs of the elbow in 45°flexion. Stage I was characterized by radiolucent areas. In stage II, nondisplaced fragments were present. Loose bodies and sclerotic change indicated stage III. Matsuura et al performed the conservative treatment on 101 patients with stage I or II lesions. Conservative treatment consisted of discontinuation of heavy use of the elbow for at least 6 months. Of 101 patients, 84 were diagnosed as stage I, with a mean age of 11.3 years and 17 were in stage II, with a mean age of 13.9 years. Of the 84 patients in stage I, healing was observed in 90.5%. In stage II, the incidence of healing decreased to 52.9%. Mean period required for healing was 14.9 months in stage I and 12.3 months in stage II. These results suggest that conservative treatment is recommended for the early stage lesions. However, little is known about the outcome of conservative treatment for asymptomatic OCD patients. The purpose of this study was to investigate 2year follow-up outcome of asymptomatic OCD in adolescent baseball players. METHODS: We retrospectively reviewed 33 baseball players aged 9-12 years (mean, 11.3 years) with asymptomatic OCD. There were 23 stage I lesions and 10 stage II lesions. We recommended the conservative treatment including stop throwing to all the players. Sixteen players (48.5%) agreed to our advice. The remaining 17 players did not follow the authors’ advice. Twelve players (36.4%) changed position or throwing side and 5 players (15.1%) did not change throwing level. Two years later, subjects were evaluated clinically and radiographically. Radiological outcome was divided into 3 types, complete repair, incomplete repair, and failure. RESULTS: Stop throwing produced complete repair in 93.7%, incomplete repair in 6.3%, and none of the failure. Changing position or throwing side produced complete repair in 41.7%, incomplete repair in 25%, and failure in 33.3%. Not changing throwing level produced complete repair in 20%, none of incomplete repair, and failure in 80% (Table 1). Players with complete or incomplete repair had not any symptom at the follow-up. On the other hand, all the players with failure had symptom such as pain and/or catching. Six of 8 players (75%) with symptom needed operation. CONCLUSION: Even in the asymptomatic early stage OCD, it is desirable to stop throwing until the healing is observed.