Matching Articular Surfaces of Selected Donor and Recipient Sites for Cylindrical Osteochondral Grafts of the Femur

Abstract

Background: Autogenous osteochondral grafting has been widely performed as a treatment for focal osteochondral defects. In this procedure, it is important to match the shape of the articular surface between the donor site and recipient site to reproduce the original articular surface of the femur. Purpose: To investigate the ideal matching patterns of articular surface profiles of donor and recipient sites for autogenous osteochondral grafting of the femur using a 3-dimensional laser scanning method. Study Design: Descriptive laboratory study. Methods: The donor and recipient sites in 11 cadaveric knees were examined, and each of the sites was divided into 12 areas. In the donor sites, the contours of the articular surface of the medial and lateral femoral trochleae were determined. In the recipient sites, the contours of the articular surface of the medial and lateral femoral condyles were assessed. Vertical intervals (VIs) were then calculated as the parameter for the height of the articular surface. The VI was the height difference from the highest and lowest points in the contours of the articular surface within the area of the donor and recipient sites. Finally, assessments were made on whether the articular surface of the donor and recipient sites matched properly for cylindrical osteochondral grafts with diameters of 6, 8, and 10 mm. Results: For the donor site, the VIs of the middle area of the femoral trochlea were significantly smaller than those of the peripheral area. For the recipient site, the VIs of the anterior area of the femoral condyle were significantly smaller than those of the posterior area. Conclusion: These results indicated in aging specimens that the articular surface profile of the middle area of the donor site matched that of the anterior area of the recipient site. On the other hand, the shape of the articular surface of the peripheral area of the donor site was congruent with that of the posterior area of the recipient site. Clinical Relevance: This study will be useful for improving donor site selection during preoperative planning. The authors recommend selection of the middle area of the femoral trochlea for cartilage defects in the anterior area of the femoral condyle and of the peripheral area of the femoral trochlea for cartilage defects in the posterior area of the femoral condyle.