BMP-2复合PLGA/磷酸三钙修复大段骨缺损的实验研究

Application of compound bone morphogenetic protein 2,polylactide coglycolic acid and tricalcium phosphate in repair of large segmental defects in radius of sheep

目的研究骨形态发生蛋白-2(Bone Morphogenetic Protein,BMP-2)复合聚乳酸-乙醇酸共聚物(Poly-Lactide-Co-Glycolic,PLGA)/磷酸三钙(Tricalcium Phosphate,TCP)修复羊大段桡骨缺损的能力。方法手术制成30mm绵羊尺、桡骨骨缺损模型,A组在桡骨缺损区植入BMP-2复合PLGA/磷酸三钙棒材,B组不植入任何材料。两组均以钢板固定桡骨缺损区。术后4、8、12、24周拍摄X片,24周时处死动物进行组织学观察。结果 X线片检查示A组术后24周桡骨缺损处完全成骨修复,皮质骨与髓腔的轮廓清晰;B组无有效骨痂形成。组织学检查示A组术后24周时骨痂外层形成皮质骨,为较成熟的板层骨,与断端皮质骨完全融合,其中央可见大量骨髓组织,未见植入材料残留;B组缺损区可见大量纤维组织填充。结论 BMP-2复合PLGA/磷酸三钙能很好的修复绵羊大段桡骨缺损,未来有望成为解决临床骨缺损的有效材料。

Objective To study the application of compound bone morphogenetic protein 2 （BMP-2）, polylactide coglycolic acid （PLGA） and tricalcium phosphate （TCP） in repair of large segmental defect in radius of sheep. Methods A 30mm-long radius and ulna defect of sheep was established by surgery. Sheep were divided into group A and group B. Sheep in group A underwent implantation of compound BMP-2, PLGA and tricalcium phosphate into their radial defect. Sheep in group B received no implantation of any material into their radial defect. Radii in both groups were fixed with steel plates. Roentgenograms were taken 4, 8, 12 and 24 weeks after operation. The animals were killed 24 weeks after operation for histological examination. Results Roentgenogram revealed that the radial defect was completely healed 24 weeks after operation with a clear contour of cortical bone and medullary cavity in group A. No effective formation of callus was found in group B. Histological examination showed that the cortical bone was formed in the outer layer of callus as a rather mature lamellar bone, which was integrated with the broken ends of fractured bones with a large amount of residual bone marrow but without residual implanted material in group A 24 weeks after operation. However, a large amount of fibrous tissues were filled in the bone defect area of group B. Conclusion Compound BMP-2, PLGA and tricalcium phosphate can repair the large segmental defects of radius in sheep.