Midterm Outcomes of Autologous Osteochondral Graft Transplantation Only in the Femoral Condyle without Treating the Tibial Plateau with Subchondral Bone Exposed.

This study aimed to examine the midterm clinical outcomes of autologous osteochondral grafts (AOG) that were performed in the femoral condyle without treating the tibial plateau with subchondral bone exposed, and to compare these outcomes with those of AOG used in patients with osteoarthritis (lateral type or medial type) or osteonecrosis. The study included 6 men and 16 women and 11 right knees and 11 left knees. The mean operative age was 56.0 years (range, 21-76 years), and the mean follow-up period was 98.4 months (range, 60-164 months). Six patients had lateral type osteoarthritis (OAL), 7 had medial type osteoarthritis (OAM), and 9 had osteonecrosis (ON). The patients' knee symptoms as their clinical outcome were evaluated using the knee scoring system of the Japanese Orthopedic Association (JOA), and the International Knee Documentation Committee (IKDC) subjective score. The postoperative clinical outcomes of the OAL and ON group were significantly better than their preoperative clinical scores and remained the same until the final follow-up. However, the clinical outcomes of OAM improved 2 years after AOG, but eventually decreased thereafter. The number of worse cases in the OAM group was significantly larger than those in the OAL and ON groups. In these procedures, the postoperative clinical outcomes of the OAL and ON groups were significantly better than their preoperative clinical scores and were maintained for about 8 years. However, the clinical outcomes of OAM improved until 2 years after AOG, but eventually decreased thereafter.