An Experimental Study On The Repairing Of Large Segmental Bone Defects Of Radius In Rabbits By New Porous Calcium Sulfate Scaffold Combined With Release Controlled Recombinant Human Bone Morphogenetic Protein-2 By Collagen I

Objective: To research the repairing effect of large segmental bone defects of radius in rabbits by new porous calcium sulfate scaffold combined with release controlled recombinant human bone morphogenetic protein-2 by Collagen I.Methods: 1. Adopt the new porous calcium sulfate scaffold made by LI Shuwei through polymeric sponge impregnation process and the modified method. 2. Choose 36 rabbits' radial bone for seventy-two bone defect models, the defect is 15mm ,then embed the support .The rabbits are randomly classified into four groups. Group C is the experiment group ,embed the new porous calcium sulfate scaffold combined with release controlled recombinant human bone morphogenetic protein-2 by Collagen I; Group A,B,D are the control group , embed new porous calcium sulfate scaffold,new porous calcium sulfate scaffold combined with Collagen I and autogenous bone individually. After operation the animals are separately sacrificed in the forth ,eighth, twelfth week .Then, carry out the following examination: X-ray examination, X-ray image analysis, bone mineral density detection, histology observation,histology image analysis, vitodynamics detection.Result: 1. The result of roentgenographic and histological examination: in each time point the group C were superior in term of the aera and the trabecular amount of new bone formed on region of bone defect to group A and B, the group B were superior to group A.In the twelfth week the repair of bone defects has no significant difference between the group C and the group D. 2. The result of X-ray image analysis: in each time point the group C were superior in term of X-ray gray value to group A (P<0.01) and B (P<0.05 ) ,the group B were superior to group A(P<0.05) . In the forth week the group D were superior to group C (P<0.05) but in the eighth and twelfth week the X-ray gray value has no significant difference between the group C and the group D(P>0.05). 3. The result of bone mineral density detection: in each time point the group C were superior to group A (P<0.01) and B (P<0.05) , the group B were superior to group A(P<0.05) ; In the forth and eighth week the group D were superior to group C (P<0.05) but in the twelfth week the bone mineral density has no significant difference between the group C and the group D (P>0.05) . 4. The result of histology image analysis: in each time point the group C were superior in term of the proportion of osteogenesis area to group A (P<0.01) and B(P<0.05), the group B were superior to group A (P<0.05); In the forth week the group D were superior to group C (P<0.05) but in the eighth and twelfth week the proportion of osteogenesis area has no significant difference between the group C and the group D (P>0.05) . 5. The result of vitodynamics detection: in the twelfth week the group C were superior in term of crushing strength to group A (P<0.01) and B (P<0.05 ) , the group B were superior to group A (P<0.05); The crushing strength has no significant difference between the group C and the group D (P>0.05) .Conclusion: 1. Like autogenous bone embeding group new porous calcium sulfate scaffold combined with release controlled recombinant human bone morphogenetic protein-2 by Collagen I can efficiently repair bone defects,it was more rapid and vigorous than other group.2. Collagen I can optimize the performance of the new porous calcium sulfate scaffold.