Influence of trypsin on the biological bonding of cartilaginous surface tobone in rabbits

Biological healing between cartilage and bone is difficult, because their h istological structure and physiological function are completely different, and the healing ability of cartilage is limited. A full-thickness articular cartilage defect was created in the femoral groove of 48 Japanese white ra bbits. The defects were filled with a piece of articular cartilage from the contralateral patella with its superficial zone facing down to the defect. Before grafting, a piece of articular cartilage was treated with 0.05% try psin or phosphate-buffered saline (PBS) for 5 min. The healing process was histologically observed at 2, 4, 8, and 16 weeks after operation. We found that the incorporation process of cartilage implant treated with trypsin wa s much better than that of PBS-pretreated cartilage. Proliferation and reor ganization of chondrocytes in the cartilage implant and subchondral bone in growth were observed in the trypsin-pretreated group. Although the observat ion period in our study was not very long, our results suggest that trypsin pretreatment might be one of the most promising methods to facilitate the repair process between cartilage and bone.