An experiment research of the composite of BMP-2 and PLGA/tricalcium phosphate with vascularized ulna in repairing the large segmental defect of sheep radius

[Objective]To study the effects of the composite of PLGA-TCP-BMP-2 artificial bone with vascularized ulna in repairing the large segmental defect of sheep radius.[Method]A 30 mm defect was made in middle segment of sheep radius.In group A,the composite of BMP-2 and PLGA/tricalcium phosphate with vascularized ulna was implanted into the radial defect.PLGA-TCP-BMP-2 artificial bone was implanted into the defect in group B.No material was implanted in group C.Plates were used to fix the bone in both groups.X ray was used to evaluate the repairing effect at 24 weeks postoperatively.Animals were sacrificed at 24 weeks after operation to make histological analysis.[Result]X ray revealed that the bone defect of radius was fully repaired at 24 weeks after operation with clear contour of cortical bone and medullary cavity in group A.While in group B,the contour was not as clear as in group A.No effective callus was found in group C.Histological study showed that the callus had already formed compact bone which integrated with broken ends of fractured bone in group A and B.Large amount of bone marrow could be seen in the middle part and no residual material was found.However,large amount of fibrous tissue was found in bone defect area in group C.[Conclusion]The composite of BMP-2 and PLGA/tricalcium phosphate with vascularized ulna could repair large segmental defect of sheep radius satisfactorily.