他汀类药物对同种异体骨移植修复兔桡骨缺损的影响

The effect of stains on allogragts bone in repairing rabbits radius segmental defects

目的观察他汀类药物对骨折愈合质量的影响及影响骨代谢的可能机制。方法制备同种异体松质骨。将36只新西兰白兔随机分为3组,在两侧桡骨干中段处造成长10mm的骨缺损,以制备骨缺损动物模型。A组为同种异体骨移植复合他汀类药物局部应用(12只),术后第1天于骨折局部皮下注射5%辛伐他汀液(5mg/kg)1次,后连续注射5天,1日2次;B组为同种异体骨复合骨形态发生蛋白移植(12只);C组为单纯同种异体骨移植(12只)。术后2、4、8、12周行大体观察、X线摄片检查、骨密度检查、病理学检查和生物力学检查。术后12周用生物力学试验机作三点弯曲试验,并与正常桡骨比较。结果术后各组均无明显的免疫排斥反应。X线摄片检查、骨密度检查、病理学检查结果表明,同种异体骨移植复合他汀类药物局部应用组(A组)无论在新骨成骨量、成骨速度和时间上均优于单纯同种异体骨移植组(C组)。术后12周的X线片和病理学检查结果显示A、B两组差别不大,基本达到骨愈合。生物力学检查结果示A组的三点弯曲试验最大应力明显高于C组(P<0.01),A组和B组无统计学差异,但B组的最大应力值略高于A组。结论辛伐他汀(10mg/kg/d)局部应用可促进兔桡骨缺损经同种异体骨移植后的骨愈合质量。

Objective To investigate the effect of simvastatin on the quality of fracture healing, the underlying mechanism of statins on bone remodeling. Methods Thirty six mature New Zealand white rabbits were randomly divided into three groups. The 10mm-long bone defects were made in both radius of each rabbit. Group A（12 rabbits）, the simple cancellous allograft bone was implanted, in the meantime 5% simvastatin（5mg/kg） were injected subeutaneously to the fracture local once on the first day of fracture and twice on the 5 days thereafter; Group B（12 rabbits）, the allograft bone scaffold loaded with bone morphogenetic protein was implanted; Group C（12 rabbits）, the simple cancellous allograft bone was implanted. The defec〉repairing capability for each of the treatment modalities was assessed by gross, X-ray examinations, the bone mineral density and histopathological examination in 2, 4, 8, 12 weeks after operation. Mechanical strength was measured by three points bending tcst in the 12th week after operation and compared with normal radius. Results No obvious immune rejection was found in all groups. With the results of X-ray examination, bone mineral density and histopathologieal examination, The group A and group B were superior than group C, using simple cancellous allograh bone planted, in terms of the amount and speed of new bone formed on region of bone defect to group C. The defects of group A and group B were basically healed by 12 weeks. The results of group A excelled those of group C in aspects of biomechanical strength of bone（P〈0.01）. There weren＇t significantly statistic difference between group A and group B, while the maximum force value of group B is slightly better than that of group A. Conclusions Local application of sim-vastatin （10mg/kg/day） can promote repairing segmental bone defects in rabbit model after cancellous allograft bone implanted.