The Effect Of Igf-1 Combined With Deproteinized Xenogenic Cancellous Bone In Femoral Head Necrosis Of Rabbit

Objective:A new bone graft material was constructed by combining insulin -like growth factor (IGF-1)with deproteinized bovine cancellous bone (DPB).The ANFH rabbit model was developed that mimics the clinical situation with trapdoor bone-grafting,in order to evaluate the feasibility to use this method to repair avascular necrosis of femoral head (ANFH) in clinic。Methods:The model of ANFH was developed in the left femoral head in 54 rabbits, of which 18 defects were implanted with IGF-1/DPB composites,18 implanted with DPB,18 implanted nothing. Dissolve IGF-1 (900ng) in aseptic distillate (15ml),then put 18 DPBs into it, the mixed powder in 4 degree centigrade refrigerator. After exposing hip joint, drill hole between femoral head and neck with 3.5mm aiguille. Get rid of 50% cancellus bone of femoral head with little curette. Put a piece of gauze which dipped in 95% alcohol into the hole and keep 30min. then plant the IGF-1/DPB and DPB into the bone defects of ANFH respectively. The specimens were harvested respectively at the end of 2 week,4 week and 8 week after operation. In order to observe the formation of new bone and the degradation process of the materials, a series of examinations were carried out including of radiograph,histomorphology, bone density.The results of IGF-1/DPB group,DPB group and control group were compared on the same condition. result:Two week after operation, there is no statistical difference between the IGF-1/DPB group and the DPB group from radiological bone density and Lane-score examination(P> 0.05), but from tissue histology of HE osteoblast-score examination, there is obviously different between the two groups(P<0.05);At 4,8 week after operation, the rate and quality of new bone formation was statistical different between the IGF-1/DPB group and the DPB group from radiological bone density and Lane-score examination(P<0.05), and there is obviously difference in tissue histology of HE osteoblast-score examination also(P<0.05).Conclusion:DPB is an ideal carrier of IGF-1.The IGF-1/DPB composite has great potential in ANFH repairing. New bone formation is better than DPB group. The speed of degradation of IGF-1/DPB was evidently higher than DPB. The animal model in the current study is a useful tool for the evaluation of methods to treat osteonecrosis of femoral head. insulin-like growth factor-1 has the potential effect in treating avascular necrosis of femoral head.