肌电图对腰神经后根节段定位作用的实验研究

Electrophysiological study of locating the segment of lumbar nerve dorsal roots in rat

目的:探讨应用肌电图行大鼠腰神经后根节段定位的方法。方法:通过电生理的方法,依次电刺激L3￣L5脊神经后根,分别记录大鼠双侧下肢主要肌肉的肌电图像,测量最早出现的感觉神经动作电位(SNAP)最大波幅值。结果:刺激L3脊神经后根,于股四头肌记录到的波幅峰值(480.8±255.9μV)显著高于其它各组肌肉(P<0.01)。刺激L4脊神经后根,于下肢四组肌肉记录到的CMAP最大波幅平均值均>100μV,其中在股四头肌(305.2±131.5μV)、胫骨前肌(340.2±310.4μV)记录到的波幅峰值显著高于在股二头肌(142.4±144.7μV)、腓肠肌(138.2±127.6μV)记录到的波幅峰值(P<0.01)。刺激L5脊神经后根,于股二头肌(377.5±264.4μV)、腓肠肌(168.4±126.7μV)记录到的波幅峰值显著高于其它各肌群记录到的波幅峰值(P<0.01)。结论:电刺激不同脊神经后根,在大鼠下肢不同肌肉记录到的SNAP的波幅峰值存在差异,综合分析记录到的SNAP的波幅峰值,可作为腰神经后根节段定位的参考。

Objective：To study the electrophysiological role in locating the segment of lumbar nerve dorsal roots in rat.Mcthod：L3-L5 never rooots of rat were stimulated by means of electrophysiological method,the maximum amplitudes of the sensory nerve action potentia（SNAP） from two subdermal needle electrode at different muscle of bilater lower limb were recorded.Result：The recorded waveform mostly was typically polyphasic wave.When stimulating L3,the maximum amplitudesrecoreded in quadriceps femoris （480.8± 255.9μV） was higher than those in other muscles significantly （P〈0.01）;When stimulating IA,the maximum amplitudes recorded in quadriceps femoris （305.2±131.5μV） and tibialis anterior （340.2±310.4μV） were higher than those in biceps femoris（142.4±144.71xV） and gastrocnemius（138.2±127.6μV） significantly（P〈0.01）; When stimulating L5 ,the maximum amplitudes recorded in biceps femoris（377.5±264.4μV） and gastrocnemius （168.4±126.7μV）,biceps femoris （121.5±120.6μV） were higher than those in quadriceps femoris （54.1±98.26μV） significantly（P〈0.01）.Conclusion：Stimulating different lumbar never dorsal rooots in rat will lead to different maximum amplitudes of SNAP （the earliest maximum amplitudes） recorded in different lower limb muscles of rat,which can been refered to locate the segment of the stimulated lumbar nerve dorsal roots.