重组合同种异体皮质骨修复大段负重骨缺损的组织计量学研究

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组织计量学效果 ,为临床大段负重骨缺损的重建提供新方法。方法 :4 0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 ,分别采用重组人骨形态发生蛋白 2 (rhBMP 2 )和Ⅰ型可吸收胶原海绵 (ACS)对各组移植骨进行处理 ,其中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 1 2周处死动物 ,移植骨和宿主骨远、近结合部及移植骨中段分别取材 ,做不脱钙磨片 ,在荧光显微镜和普通光镜下测量新骨形成率、骨孔隙率、骨单位半径和哈佛氏管直径。结果 :A组在新骨形成率、骨孔隙率、骨单位半径和哈佛氏管直径等方面均优于B、C、D组 ,与E组相仿。结论 :同种异体皮质骨、rhBMP 2和ACS复合移植具有高效持续的骨诱导作用 ,能平衡骨吸收 /骨形成活动 ,移植骨愈合质量好 ,是修复大段负重骨缺损的好方法。

Histomorphometric Study on the Repairing of Massive Loaded Bone Defects with Recombinant Cortical Allograft

Objective: To compare the histomorphometric effect of repairing of massive loaded bone defects in rabbits by frozen cortical allograft dealt with different ways and to provide new approaches for the remodeling of clinical segmental loaded bone defects. Methods: Forty New Zealand white rabbits were divided into 5 equal groups randomly and all were cut 2 cm bone defect in left thighbone. Type Ⅱ recombinant human bone morphogenetic protein (rhBMP 2) and type Ⅰ absorbable collagen sponge (ACS) was used to treat allografts. Group A, B, C, D, E was implanted with allograft+rhBMP 2+ACS, allograft+rhBMP 2, allograft+ACS, allograft and autograft respectively. All rabbits were sacrificed after 12 weeks and specimens were taken from the proximal and distal allograft host junction and mid diaphyseal portion of allografts for producing non decalcified sections. Parameters including new bone formation rate, bone porosity, osteon radius and diameter of Haversian canal were measured under fluorescent and regular light microscopy. Results: Like group E, group A excelled at the performance of new bone formation rate, bone porosity,osteon radius, and diameter of Haversian canal as compared to group B, C, D. Conclusion: The transplantation of allograft combined with rhBMP 2 and ACS is appropriate for the repairing of massive loaded bone defects, which has high and durable osteoinductivity, balances bone resorption and bone formation and enhances the healing of allografts.