Arthroscopic osteochondral transplantation: Histologic results

Purpose: Localized, full-thickness articular cartilage defects of the femoral condyle are challenging. This report presents the histology of clinical cases obtained at intervals from 2 to 12 months after arthroscopic osteochondral transplantation. Type of Study: Longitudinal cohort study. Methods: Patients found at arthroscopy to have full-thickness femoral condyle defects between 1 and 3.5 cm in diameter underwent arthroscopic osteochondral transplantation. Exclusion criteria were associated tibial defects, patellar defects, or generalized arthritic change. The grafts taken from the superior and lateral intercondylar femoral notch were press-fit into holes drilled into the defect starting adjacent to the articular cartilage margin. Cancellous bone bridges were maintained between grafts. At various time intervals from 2 to 12 months after the osteochondral transplantation, arthroscopic biopsy specimens of the recipient sites were obtained. Results: Ten patients (5 male, 5 female) enrolled at 2 centers were evaluated arthroscopically at various intervals up to 13 months after osteochondral transplantation. The average patient age was 40 years (range, 17 to 65 years). One to 3 plugs had been harvested and inserted. Seven patients underwent biopsy at intervals ranging up to 12 months postoperatively. All showed maintenance of the integrity of the grafts with living chondrocytes and osteocytes. Donor sites filled without grafting and were covered with fibrocartilagenous scar. No complications occurred in this group. Conclusions: These histologic results suggest that arthroscopic osteochondral transplantation is a viable alternative for treating full-thickness chondral defects, with the grafts retaining their integrity and living chondrocytes and osteocytes observed in the grafts for up to 12 months after implantation.