长段同种异体骨与自体活骨复合移植的实验研究

目的 研究长段同种异体骨与带血管腓骨套叠式复合骨移植体的愈合机制和规律。方法 采用健康成年杂种犬36只胫骨结节下切除3．0cm骨干和骨膜实验动物模型。随机分为实验组和对照组。实验组植入深低温保存的同种异体骨与带血管自体腓骨，对照组仅植入深低温保存的同种异体骨，均用7孔93cmAO加压钢板内固定及石膏外固定。术后1、2、3、4个月分别行X线摄片、ECT检查、大体标本及组织学观察。结果 X线示实验组较同时期对照组异体骨吸收、新骨形成明显，第4个月实验组宿主骨一异体骨接合部愈合率83．3％，对照组未愈合或不愈合。ECT检查：实验组较同期对照组骨代谢活跃，但变化规律相似，均为术后1、2个月活跃，于第2个月达高峰，第3、4个月呈下降趋势。组织学观察：实验组较同期对照组异体皮质骨髓腔内壁及哈佛管内的内吸收、成骨活动显著增强。结论 长段同种异体骨与带血管自体腓骨复合移植修复骨缺损效果良好，带血管自体腓骨能促进长段同种异体骨的血管化，加速其爬行替代过程。

Experimental study on the transplantation of massive allograft combined with vascularized fibulr autograft

Objective To investigate the mechanism and characteristic of bone transplantation of massive allografts combined with vascularized fibular autografts. Methods The bone massive defect animal models were made adult dogs at the shaft of tibia below the tibial tuberosity which remove 3.0cm of diaphysis and periosteum.36 dogs were randomly divided into experimental and control groups.The bone defects were filled with either a frozen allograft combined with the ipsilateral vascularised fibular in experimental group,or a massive frozen allogeneic cortial bone alone in control group.Outcome assessment included X-ray,bone scintigraphy examinations,gross specimen as well as histological studies at the 1,2,3,4 months postoperative. Results In the same period,radiographic evaluation of the allogeneic cortial bone and junctions between allograft bone revealed significantly allograft bone resorption,Greater new bone formation and larger osteon radii in experimental group compared to control group.The healing rates of osteosynthesis were 83.3% by 4 month in experimental group,while no connection could be observed in control group.ECT showed that,In the same period,bone metabolism was more active in experimental group compared to control group.Bone metabolism was more active at 1,2 months,and it reached its peak by 2 months,then it had a decreasing tendency at 3,4 months postoperatively.Histological observation showed that,in transverse sections of allografts significantly higher bone turn over occurred in the inner cortical area of the allografts as compared to the outer cortical and mid-cortical areas in experimental group.While in control group,significantly little bone turn over occurred in the inner corical area of the allograft as compared to the out cortical and mid-cortical areas. Conclusion Massive allogeneic cortial bone combined with vascularized fibular autografts are useful in the reconstruction of massive bony defects.Vascularized fibular accelerated the vascularization and creeping substitution of the massive allogeneic cortial bone.