Arthroscopic resection of a chondroblastoma in the knee.

A 13-year-old boy with the diagnosis of osteochondritis dissecans underwent arthroscopic examination of his knee joint. At surgery a cartilaginous mass in the medial femoral condyle was identified. Biopsy samples confirmed the diagnosis of chondroblastoma, which was removed completely through the arthroscope. A second arthroscopic examination of the knee was conducted at 6 months, and showed no residual disease. Clinical and radiographic follow-up of the affected joint 5 years after surgery was satisfactory. Arthroscopic removal of an intra-articular tumor is an attractive treatment alternative, provided the lesion is accessible and there is no suggestion of a malignancy.