Pathophysiology of lumbai radiculopathy -A study of ectopic finng-

坐骨神经痛是一种典型的神经性疼痛，见于腰椎管狭窄和椎间盘突出。然而，坐骨神经痛的发病机制尚不清楚。近年来，神经根的异位放电已被发现在坐骨神经痛的发病中起重要作用。在本研究中，建立了一个分析异位放电的模型。然后观察静脉淤积、缺氧、神经元活动增加、交感神经作用、手术减压和各种药物的影响。实验记录了大鼠腓肠神经的异位放电。慢性腰椎管狭窄大鼠自发性频率增高，静脉淤滞缺氧引起的放电增多，表现为病理改变。后肢神经或交感神经的激活也增加了归档频率。研究结果被认为与间歇性跛行等临床症状有关。静脉淤滞引起的神经根血流变化也通过多普勒血流仪证实。腰椎管狭窄症的治疗方法包括手术减压、药物治疗和阻滞治疗。本研究结果为了解腰椎管狭窄的病理生理学提供了重要信息。

Sciatica is a representative neuropathic pain seen in lumbar spinal canal stenosis and disk herniation. However the pathogensis of sciatica is poorly understood. Recently, ectopic firings in the nerve root has been found to play an important role as an origin of sciatica. In the present study', a model to analyze the ectopic firing was established. Then the effects of venous stasis, anoxia, increased neuronal activity, sympathetic action, surgical decompression and various drugs were investigated. In the experiments, ectopic firing was antidromically recorded from sural nerve of rats. In the rats with chronic lumbar spinal canal stenosis, increased spontaneous frequency and an increase of firing by venous stasis and anoxia were characterized as pathological changes. Activation of hindlimb nerve or sympathetic nerve increased filing frequency as well. The findings obtained in the study were thought to be related to the clinical symptoms such as intermittent claudication. The changes of nerve root blood flow due to venous stasis was also confirmed by a lazor-doppler flowmeter. The therapeutic treatments for lumbar stenosis such as surgical decompression, medications and blocks were found to be effective. The results obtained in the present study provided improtant information to understand the pathophysiology of lumbar spinal canal stenosis.