In this study the effectiveness of the application of cancellous autogreft in the repair of the osteochondral defects created experimentally in the knee joint of the dogs was evaluated.

In the study, 12 mature dogs between 20-35 kg of weight were used. After anesthesia was maintained by Rompun followed by Ketalar, genu joint was exposed through lateral para patellar approach. A defect with 8 mm diameter and 10 mm deep was created on femoral sulcus by sliding patella aside. The same operation was repeated in both legs. While the defects in the right leg was filled by autogenic cancellous greft taken from metaphysial region of tibia the defect in the left leg was left empty for the control consideration.

The small lameness was seen in all cases ten days after the operation, dissappeared afterward in the histopatological examination while regeneration and reparation formations were seen in the bone and cartilage components in the control and greft applied groups in the second month, focal fibrocartilagenous formation was observed to be started in the greft applied group in the 4^th month. In 10 to 12 ^th month, the defects were filled up completely with fibrous cartilage. In the control group, however, a small fibrocartilagenous formation was detected only in the 8 ^th month. In the 10 ^th and 12 ^th month, the defect surface was seen to have been covered by fibrocartilagenous structure but femoral sulcus remained unfilled in the control group level.

As a result, it was suggested that cancellous bone grefts could be used as regeneration accelerator for repair of large osteochondral defect.