急性牵拉对大鼠坐骨神经及相应脊髓的影响  

Study of the rat sciatic nerve and its corresponding spinal cord following the acute pulling of the rat sciatic nerve

作　　者：周丹[1] 刘璠[2] 

机构地区：[1]嘉兴学院医学院外科学教研室,浙江314001 [2]南通大学附属医院骨科

出　　处：《交通医学》2011年第2期118-120,125,共4页Medical Journal of Communications

摘　　要：目的:探讨SD大鼠坐骨神经延长致瘫的"临界长度"和"下肢安全延长率",为发育性髋关节发育不良患者行人工全髋关节置换术时,避免坐骨神经损伤提供实验研究数据。方法:将SD大鼠24只根据其后肢延长不同长度随机分成4组,每组6只,分别为0mm组,2mm组,4mm组和6mm组。以右侧后肢作为实验延长侧,左侧后肢作为正常对照侧。实验延长侧行右侧后肢股骨干中段横形截骨并行一次性延长,用自制髓内钉与骨延长维持器固定。术后第5天检测SD大鼠坐骨神经干胫骨前肌的复合肌动作电位的波幅与潜伏期。光镜下观察坐骨神经及L6节段脊髓的前角运动细胞。结果:4mm组﹑6mm组复合肌动作电位指标与对照侧比较差异有统计学意义(P<0.05)。4mm组实验延长则复合肌动作电位幅值较正常对照侧下降41.3%,为正常对照侧58.7%,两者比较差异有统计学意义(P<0.05)。潜伏期则为正常对照侧的2.5倍,两者比较差异有统计学意义(P<0.05),SD大鼠后肢延长为原后肢长度的12.1%时,即引起轴突损伤。结论:SD大鼠后肢延长到一定极限值时,有可能引起轴突损伤,髓鞘的结构也随之开始发生变化,从而影响了神经电生理信号的传递。Objective：To discuss ＂the critical length＂ and ＂the limb safe extension rate＂ through research on functional parameter of the SD rat sciatic nerves,thus providing some empirical and scientific data for the clinical treatment for DDH patients.Methods：24 SD rats were randomly divided into 4 equal groups according to the prolonged extent of hind limbs： the 0mm group,the 2mm group,the 4mm group and the 6mm group.In the research their right posterior limbs were regarded as the experimental side,while their left posterior limbs were regarded as the normal control side.Posterior limbs on experimental sides undergo the femoral osteotomy and been given ones time prolongation,and the self-made intramedullary nail and bone maintenance machine was used as the internal fixation.In the 5th day after surgery,each pair of the experimental side and the normal control side was observed in order to detect any changes in amplitude and latency of compound muscle action potentials and sciatic nerves and anterior horn efferent（motor） neurons of its L6 spinal cord of the normal control group and the experimental side were observed under the light microscope.Results：There is obvious difference between the experimental side and the normal control side（P0.05） in indexes of CMAPs in the 4mm and 6mm groups.In the 4mm group,amplitudes of CMAPs of the experimental side descend by 41.3%,while by 58.7% for the normal control side.And latency of CMAPs is 2.5 times that of the normal control side.When the length of the extension over the posterior limb length is 12.1% of the SD rat neuroaxon damages will be caused.Conclusion：Probably neuroaxon damages will be caused and the form of medullary sheath whill become irregular when the posterior limb of the SD rat prolongs to a certain extreme limit,thus influencing signal delivery of nerve electrical physiology.

关 键 词：发育性髋关节发育不良 急性牵拉 下肢延长 坐骨神经 脊髓 复合肌动作电位 SD大鼠 

分 类 号：R684[医药卫生—骨科学]