脊髓损伤继发骨质疏松大鼠腰椎骨质量变化

The influence of spinal cord injury on lumber vertebra bone mass density and bone biomechanical characterization in SD rats

目的:探讨脊髓损伤(spinal cord injury,SCI)对大鼠腰椎骨质量的影响,揭示SCI继发骨质疏松(osteoporosis,OP)特点。方法:60只SD大鼠随机分为6组,对20只采用脊髓横断法在T10处横断脊髓制作完全性SCI模型,分为SCI6周和12周组;20只在同水平处切断棘突、椎板制作假手术对照组(sham),分为Sham6周和12周组;另20只分为正常6周和12周对照组。分别在SCI后6周和12周时取材,进行腰椎骨密度(bone mass density,BMD)和生物力学性能测试。结果:SCI6和12周时,大鼠L5BMD较对照组无明显改变(P>0.05);SCI6周时L5载荷和结构刚度均较对照组出现显著降低(P<0.01、P<0.05),SCI12周时,其最大载荷和结构刚度与对照组差异仍具有显著性意义(P<0.001、P<0.05)。结论:SCI6、12周时大鼠腰椎BMD较对照组无明显变化,但SCI6周时其生物力学性能较对照组出现明显损害,12周时,其损害进一步加重。

Objective：TO determine the change of lumbar vertebra bone mass density （BMD） and biomechanical characterization in rats with spinal cord injury（SCI）.Method：Sixty SD rats were randomly divided into control groups （40eases） and experiment groups （20cases）.The rats of experiment group were transected at the tenth thoracic vertebra to make models of SCI ,and control group included normal control groups and sham operation groups in which the rats underwent a sham procedure. At SCI 6 and 12 weeks, the L5 bone BMD and biomechanical characterization were examined respectively with dual-energy X-ray absorptiometry （DUEX） and lumbar vertebra Compressive Test.Result： Comparing with control groups,the L5 BMD in rats with SCI didn＇t changed significantly （P〉0.05）,while the maximal load and structural rigidity of L5 reduced after SCI 6 weeks and 12 weeks（P〈0.01 ,P〈0.05,P〈0.001 ,P〈 0.05）. Conclusion：The L5 BMD doesn＇t change in rats after SCI at 6 weeks and 12 weeks yet, the biomechanical characterization was damaged significantly.