游离骨膜与复合rhBMP2的异种骨联合移植修复骨缺损的实验研究

Combined use of rhBMP2/BCB and free periosteum in repairing segmental defects in radii of rabbits

目的 探讨复合基因重组人ＢＭＰ２（ｒｈＢＭＰ２）的异种骨与游离骨膜（ＦＰ） 联合移植修复节段性骨缺损的效果。 方法 将ｒｈＢＭＰ２ 与去抗原牛松质骨载体（ＢＣＢ）复合，制成ｒｈＢＭＰ２／ＢＣＢ；选用新西兰大耳白兔２８ 只，制成桡骨干１５ ｍｍ 缺损动物模型，分别行ＦＰ和ｒｈＢＭＰ２／ＢＣＢ复合移植（ｎ＝６） 、ｒｈＢＭＰ２／ＢＣＢ移植（ｎ＝６） 和单纯ＢＣＢ移植（ｎ＝２）；术后４、８、１２ 、１６ 周取材，通过Ｘ线、生物力学、骨密度、组织学等手段进行对比研究。 结果 单纯ｒｈＢＭＰ２／ＢＣＢ移植，可在１６ 周使节段性骨缺损基本修复，其机制同过程与重组合异种骨相似；ｒｈＢＭＰ２／ＢＣＢ与ＦＰ联合移植，在骨缺损修复早期（ ≤１２ 周） ，其成骨速度及成骨质与量均优于单纯ｒｈＢＭＰ２／ＢＣＢ 移植，约在１２ 周使骨缺损基本修复。 结论 ｒｈＢＭＰ２／ＢＣＢ移植和ｒｈＢＭＰ２／ＢＣＢ 与ＦＰ 联合移植两种方法均可有效地修复节段性骨缺损，但以ｒｈＢＭＰ２／ＢＣＢ与ＦＰ联合移植较为理想，该方法同时具有良好的骨生成、骨传导和骨诱导作用。

Objective To study the efficacy of combined use of rhBMP2/BCBand free periosteal graft in repairing segmental bony defects. Methods A new grafting material (rhBMP2/BCB)was made by combining recombinant human BMP2(rhBMP2) and an antigen free bovine cancellous bone (BCB) as a carrier. rhBMP2/BCB was used alone in conjunction with free periosteal graft to repair a 1.5cm defect in the radius of the rabbit. The defect repairing capability for each of the treatment modalities was assessed radiographically, biomechanically, and by densitometry and histological studies. Results rhBMP2/BCB used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mechanism seen with RBX. Combined use of rhBMP2/BCB and free periosteal graft was superior in terms of increased amount and quality of the new bone formed at the early stage of the repair process (within 12 weeks) to rhBMP2/BCB used in isolation, with the defect basically healed by 12 weeks. Conclusions Both methods are effective in repairing segmental bony defects, with rhBMP2/BCB used in conjunction with free periosteal graft being most preferred, considering the satisfactory osteogenesis, osteoconduction and osteoinduction.