重组合冷冻同种异体皮质骨修复大段负重骨缺损的实验研究

目的 比较不同处理方式的深低温冷冻同种异体皮质骨修复兔大段负重骨缺损的效果，为临床大段负重骨缺损的重建提供新方法．方法 40只新西兰大白兔随机分为5组，造成左侧股骨中上段缺损2cm的模型，A组植入异体骨 rhBMP-2 ACS，B组植入异体骨 rhBMP-2，C组植入异体骨 ACS，D组单纯植入异体骨，E组植入自体骨。术后3、6、9、12周照X线片，观察骨愈合情况并测量骨痂形成面积。术后12周处死动物，对标本进行三点弯曲力学测试，检测新骨形成率、骨孔隙率。结果 A组在X线表现、骨痂形成面积、三点弯曲破坏负荷、新骨形成率及骨孔隙率等方面均优于B、C、D组，与E组相仿。结论 同种异体皮质骨、rhBMP-2和ACS复合移植既具有高效持续的骨诱导作用，又能提供足够的机械强度，是修复大段负重骨缺损的好方法。

An Experimental Study on the Repairing of Massive Loaded Bone Defects with Recombinant Frozen Cortical Allograft

Objective To compare the effect of repairing of massive loaded bone defects in rabbits by frozen cortical allograft dealt with different ways and provide new approaches for the remodeling of clinical segmental loaded bone defects. Methods 40 New Zealand white rabbits were divided into 5 equal groups randomly which were created 2 cm bone defect in the left thighbone. Group A, B, C, D and E were implanted allograft+rhBMP-2+ACS, allograft+rhBMP-2, allograft+ACS, allograft and autograft correspondingly. All groups were received X-ray test after surgery at 3 weeks interval to observe the healing of allograft and measure area of callus. All rabbits were sacrificed 12 weeks after surgery and the specimens were detected for the rate of new bone formation and bone porosity and maximal three-point-bending load. Results Like Group E, Group A excelled Group B,C and D in the performance of X-ray, callus formation, maximal bending load, new bone formation rate and bone porosity. Conclusion The transplantation of allograft combined with rhBMP-2 and ACS was appropriate for the repairing of massive loaded bone defects, which not only had high and durable osteoinductivity but also maintained adequate strength of bone.