Preparation of prefabricated vascularized bone graft with neoangiogenesis by combination of autologous tissue and biodegradable materials

Prefabricated vascularized bone grafts have previously been prepared by combining an autologous vessel bundle with auto-particulate cancellous bone and marrow (PCBM) and a biodegradable membrane. Only small quantities of low-density vascularized bone tissue have been formed using this method. The authors of the present study combined β-tricalcium phosphate (β-TCP), a biodegradable ceramic, with a prefabricated vascularized bone graft to augment osteogenesis. A saphenous vessel bundle from a rat was wrapped in a biodegradable membrane. Then, autologous PCBM was mixed with β-TCP granules and packed into the rolled membrane. In the control group, β-TCP was omitted. Bone formation was histologically assessed 6 and 9 weeks after implantation. The volume of newly formed bone tissue in the rolled membrane was greater in the presence of β-TCP granules than in the control. Microvessels had formed throughout the new bone tissue. When a prefabricated vascularized bone graft was onlay-grafted to the femur of the same rat, the prefabricated vascularized bone graft directly fused to the cortical surface of the femur, with no intervening fibrous tissue. These findings suggest that β-TCP in combination with PCBM enhances the volume and density of bone tissue in prefabricated vascularized bone grafts.