Clinical outcome and histologic findings of costal osteochondral grafts for cartilage defects in finger joints.

PURPOSE

For the purpose of achieving anatomical reduction as precisely as possible, we performed osteochondral grafting from the costo-osteochondral junction in 16 patients (17 joints) with posttraumatic articular cartilage injury or avascular necrosis in finger joints. The purpose of this study was to review our series of costal osteochondral grafts in order to determine the practicality, effectiveness, and functionality of this grafting technique in a clinical setting.

METHODS

Patients were followed for at least 18 months postoperatively (18-57 months; average, 28 months). The injured joints included 3 metacarpophalangeal, 9 proximal interphalangeal, 3 distal interphalangeal, and 2 thumb interphalangeal joints. The defect accounted for 50% to 100% of the articular surface (average, 63%).

RESULTS

The average time until bone union of the graft was 58 days. The mean arc of motion was 13 degrees before surgery versus 58 degrees after surgery, with a mean increase of 45 degrees . In 7 patients (8 joints), an extremely small portion (approximately 1 x 1 mm in size and thinner than 0.1 mm) of the implanted cartilage was obtained via biopsy using a scalpel with the consent of the patient at the time of screw removal and was used to prepare histologic specimens, which revealed scattered chondrocytes within the matrix without differences from normal hyaline cartilage in any. The chondrocytes in the grafts appeared viable, and the reconstruction of the joint surface could be confirmed histologically.

CONCLUSIONS

Osteochondral grafting from the costo-osteochondral junction achieves excellent reconstruction of the injured joint without affecting other joints. This technique is particularly beneficial in cases where it is difficult to obtain allograft donors, as is often the case in Japan. Despite these encouraging findings in this small series, we believe that it is necessary to conduct further studies of this method over a longer period.