Reconstruction of critical size segmental femoral diaphyseal defects of New Zealand rabbits by using combined titanium mesh cage and induced membrane technique.

Abstract

Long bone defects due to fractures resulting from high-energy trauma, infections and tumor resections are problems that orthopedic surgeons commonly face. We investigated the effects of a titanium mesh cage on bone healing with an induced membrane technique. Three groups, each composed of eight rabbits, were formed. Extraarticular diaphyseal bone defects were created. Femora of the first group were fixed with an empty titanium mesh cage and two K-wires. After formation of the defect, polymethylmethacrylate was inserted and fixed with a K-wire in the second group. At the third week, the cement was removed, a sterilized cancellous graft-filled titanium mesh cage was placed into the defect, and the membrane that was previously formed over the cement was placed on the cage and repaired. In the third group, sterilized cancellous grafts were filled into the titanium mesh cage, and the titanium mesh cage was fitted into the bone defect area. At the end of the third month, all subjects were killed. Radiological data revealed that the healing of the bone in the second and third groups was significantly better than that in the first group. There was no difference between the second and third groups. A histological evaluation of the healing status, such as fibrous tissue, cartilage tissue and mature or immature bone formation, was performed. Histological healing in the second and third groups was also significantly better than that in the first group. We concluded that the combination of membrane-induced bone healing and graft-filled titanium mesh cages expedites osteogenesis in extraarticular bone defects.