骨质疏松性骨折模型建立与磁场对骨折愈合的影响

目的:SD大鼠去卵巢后形成骨质疏松症模型后行肋骨切断性骨折手术,观察旋转恒定强磁场作用对大鼠骨质疏松性骨折愈合的影响。方法:建立骨质疏松肋骨骨折模型,手术后分组饲养。实验组在旋转强恒磁场下暴磁处理,强度0.4T,旋转频率6 Hz,持续30d,对照组不经磁场处理。分别在第10、20、30天处死SD大鼠,取骨痂部位做石蜡切片,HE染色,观察组织细胞形态,进行形态学计量。结果:在暴磁第10天两者并未出现明显差异;但在第20天暴磁组的骨痂发育明显优于对照组;暴磁30d之后暴磁组的骨组织重建过程得到明显的促进,实验组骨生成细胞、骨小梁数量多,排列规则致密。两侧的编织骨间隔比对照组少99.6μm,软骨细胞相对面积百分比也比对照组少25.61%。结论:肋骨骨折模型具有非负重性的特点,是一个良好的实验模型;0.4T强度下旋转恒强磁场对骨质疏松性大鼠肋骨骨折的愈合具有促进作用。

Establishment of Osteoporotic Fracture Model and the Influence of Magnetic Field on Fracture Healing

Objective：To establish an osteoporotic fracture model and investigate the biological effects of rotating constant magnetic field on fracture healing.Methods：Osteoporosis model was established by removing ovaries of female SD rats and then implemented rib fracture to establish osteoporotic fracture model.After that,model rats were randomly divided into control group and the treated group which were exposed to rotating constant magnetic fields at 0.4T,6Hz,2hrs per day for 30 days.The rats were sacrificed at day 10,day 20 and day 30 respectively during the exposure and osteotylus was collected for HE staining.Results：There were no significant differences after 10 days exposure,but the recovery of osteotylus morphology was better than the control group after 20 days exposure.At the 30th day,osteotylus in the treated group got a better reconstruction morphology with more osteoblast,bone trabecula and compacter arrangement.Moreover,the fibrous bone gaps were decreased by 99.6μm and the relative area ratio of chondrocyte was reduced by 25.61% compare with those of control group.Conclusion：Rib fracture model is a stable non-heavy bearing model,and osteoporotic fracture healing can be accelerated under 0.4T magnetic field exposure.