Thirty-eight-year Outcome of Osteochondral Autograft Transplantation Done for Medial Femoral Condyle Osteochondritis Dissecans: A Case Report

Osteochondral autografts can be used to treat full-thickness cartilage defects. In 1985, we reported two cases of osteochondral autograft transplantation with the goal of repairing osteochondral defects in the knee joints of patients with osteochondritis dissecans using hyaline cartilage. Since then, osteochondral autograft transplantation, mosaicplasty, autologous chondrocyte transplantation, and allogeneic osteochondral transplantation have been developed and implemented as treatments for osteochondral defects. However, the long-term outcomes of these treatment modalities have not been hitherto reported.

The patient was a 21-year-old man. He had medial extended type left knee joint osteochondritis dissecans osteochondral autograft transplantation was performed in 1980. The osteochondral defect measured 28 × 20 × 7 mm (length × width × depth) and extended anteroposteriorly from the center of the medial femoral condyle (MFC) to the intercondylar fossa. A piece of osteochondral autograft was collected from the medial side of the trochlea and transplanted to the crater. Cancellous bone with cortical bone was transplanted from the ilium to the osteochondral collection site.

There were neither subjective symptoms nor abnormal objective findings in the knee 38 years after. Radiographs showed small osteophytes in the medial tibiofemoral joint, and the patella skyline view showed a narrowing of the medial patellofemoral joint space. On computed tomography, the bony part of the transplanted osteochondral autograft was fused with the surrounding bone tissue, and the trabecular pattern was similar to that of the original bone. A coronal section of a magnetic resonance imaging scan showed that the signal intensity of the transplanted cartilage was similar to that of the adjacent native cartilage. In the patellofemoral joint, the cartilage of the medial facet of the patella and trochlea was uneven.

We reported 38-year outcomes in a patient who underwent osteochondral autograft transplantation in the knee joint. There were neither subjective symptoms nor abnormal objective findings in the knee. Imaging findings showed that a piece of osteochondral autograft filled the crater in the femoral condyle, and the superficial cartilage was considered to be alive.

The osteochondral margin of the trochlea should have been left when collecting the large graft from the trochlea. Further long-term follow-up is required.