Acidic fibroblast growth factor combined with partially deproteinized bone in repair of early-stage avascular necrosis of the femoral head in rabbits A histological study / 中国组织工程研究

ABSTRACT

BACKGROUND: Previous studies have demonstrated that acidic fibroblast growth factor (aFGF) combined with partially deproteinized bone (PDPB) (aFGF/PDPB) well promotes avascularization in animals with early-stage avascular necrosis of the femoral head (ANFH), but the histological results remain unknown.OBJECTIVE: To observe the histological repairing effects of aFGF/PDPB on early-stage ANFH in rabbits. METHODS: New Zealand rabbits were established models of bilateral ANFH and were randomly divided into a blank group, a simple PDPB group, and an aFGF/PDPB group. PDPB and aFGF/PDPB bone were implanted into the PDPB and aFGF/PDPB group accordingly. The blank group did not receive any implantation. At 2, 4, and 8 weeks after surgery, all animals were sacrificed for histological examination to observe the osteogenesis by hematoxylin-eosin staining.RESULTS AND CONCLUSION: Defects were filled with granulation tissues and fibrous connective tissues, only a little osteoid tissue formed at the borderline in the blank group at the end of the 8th week. In the PDPB group, a little new bone and cavitas medullaris formed. At 8 weeks, lots of graft was absorbed and cavitas medullaris formed with more osteoplasts and myeloid cells in it. The osteogenesis in the aFGF/PDPB group was better than that of PDPB group in each time point. At 4 weeks, the transplanted cavity was filled with osteoid tissues, a lot of osteogenic precursor cells and osteoblasts could be seen. Plenty of micrangium was observed, and osteoid tissues began to rebuild. At 8 weeks, the graft was replaced by bone tissues, and cavitas medullaris were formed with lots of bone marrow cells in it. At the borderline of the bone trabecula, there were lots of osteoplast and little osteoclasts, which may play a role in bone remodeling. There were mature bone cells in bone lacuna. Results indicate that aFGF/PDPB has better repair effect on rabbit model of ANFH than that of simple PDPB.