Abstract: Objective To observe the efficacy of a kind of complex composed of biphasic ceramic biologic bone (BCBB), bone morphogenetic protein (BMP) and basic fibroblast growth factor (bFGF) on the repair of necrotic areas of the femoral head. Methods The femoral head necrosis model of 64 femoral heads in 32 rabbits induced with microwave heating were randomly divided into four groups, which implanted with nothing (group A), BCBB/BMP (group B), BCBB/BMP/bFGF (group C) and with cancellous bone autograft (group D). The specimens were harvested separately at the end of 2, 4, 8 and 12 weeks after operation. 4 femoral heads were taken off at each interval in every group. A series of examinations were carried out including of naked eyes and gross anatomic observation, X-ray, histology, and blood vessel immunohistochemical staining. Results In group A, 1 femoral head collapsed by the end of 12 weeks, and there was only a little osteoid tissue formed. At the same time, a lot of new bone formed in group B and group C, and the boundary between the bone grafting area and the post bone still existed, but the boundary was unclear in group D, with the density consistent to the post bone. Under X-ray, the defect could be found and one femoral head collapsed in group A by the end of 12 weeks. The density of bone grafting area was high and the boundary to the post bone was unclear in group B and in group C. The density of bone grafting area was the same as the post bone and the boundary between them was unclear in group D. There was only a little osteoid tissue formed in group A by the end of 4 weeks. At the same time, there was a little new bone formed in group B, and BCBB was partly degraded. There was a lot of new bone formed in group C and group D, and BCBB was partly degraded in group C, but cancellous bone autograft was almost absorbed in group D. The new bone area by the end of 4, 8 and 12 weeks from more to less were: group C and group D (P>0.05), group B, and group A (P<0.05). At the end of 2, 4 and 8 weeks, the blood vessel area of group C was more than that of group A, group B, and group D (P<0.05). Conclusion The BCBB/BMP/bFGF complex can induced osteoinduction and revascularization, to repair rabbit femoral head necrosis as effective as cancellous bone autograft.

Key words: femoral head necrosis, biphasic ceramic biologic bone, bone morphogenetic protein, basic fibroblast growth factor, repair