Identifying Potential Optimal Donor Graft for Talar Osteochondral Transplantation: A Finite Element Analysis of Different Femoral Condyle Sites

PURPOSE: To compare the biomechanical performance of different femoral condyle donor sites for autologous osteochondral transplantation (AOT) of the talus. METHODS: Patient-specific finite element models were constructed based on postoperative computed tomography (CT) scans from 17 individuals with cystic osteochondral lesions of the talus (OLT). The femoral condyles were divided into six distinct donor sites: the medial superior (MS), medial central (MC), medial inferior (MI), lateral superior (LS), lateral central (LC), and lateral inferior (LI) regions. Finite Element Analysis (FEA) was employed to simulate the biomechanical response under a simulated standing load, quantifying von Mises stress, displacement, and strain. RESULTS: No significant differences were observed in mean stress or mean strain among graft from different femoral condyle sites (P > 0.05). MS graft exhibited significantly lower displacement compared to the mean displacement of the talar articular surface (P = 0.002), and also showed significantly reduced displacement relative to all other donor sites (P < 0.05). No significant differences were observed in mean stress or strain among other femoral condyle graft sites (P > 0.0028 Bonferroni correction). CONCLUSION: In AOT using the femoral condyle as the donor site, stress distribution did not differ significantly across different donor regions; however, the medial superior (MS) region showed relatively small displacement.