Nineteen patients with 20 osteochondritis dissecans lesions were evaluated between 2 and 20 years after excision of a partially detached (grade III) or loose (grade IV) fragment from the femoral condyles. Evaluation with the Hughston rating scale for osteochondritis dissecans revealed one excellent result, four good, four fair, six poor, and five failure results, Eleven patients had developed osteochondritis dissecans before skeletal maturity, In contrast to what has been stated in the literature, the results in these patients were no better than in those who developed osteochondritis dissecans as adults. The short-term results of excision are good, but the long-term results are extremely poor. Consequently, we recommend bone grafting and replacement of the fragment when it is technically possible because the long-term results are better than those after excision.