AN EXPERIMENTAL STUDY OF THE DOUBLE CRUSH SYNDROME IN SCIATIC NERVE OF RABBIT

简介：为探讨双侧挤压伤对兔坐骨神经损伤的影响，采用成年家兔，体重3200 g左右。暴露右侧坐骨神经，在近端和远端放置硅胶管带（双重卡压组; A组），仅在近端放置硅胶管带（单一近端卡压组; B组）或在远端放置硅胶管带（单一远端卡压组; C组）。导管的近端直径为2.0 mm，远端直径为1.5 cm。6 ~ 12周后，采用^3 H-亮氨酸对形态学表现、运动传导速度（MCV）和快速轴索血流进行评估。宏观上，A组1只兔在近端卡压带近端见小假神经瘤，B组3只兔在远端卡压带近端见小假神经瘤，C组B和B组各1只兔在远端卡压带近端见小假神经瘤分别光镜下，A组3只兔的6个卡压区均有脱髓鞘，B组和C组各3只兔的3个卡压区均有脱髓鞘。脱髓鞘程度A组以远端卡压区最明显，A组以近端卡压区最明显，B、C组以弱至轻度脱髓鞘。B和C组各3只家兔均正常，而A、B和C组中，所有陷获区近端的^3 H-亮氨酸升高，A组兔近端和远端卡压区均明显升高。讨论：从形态学和电生理检查结果以及快速轴突流动评估结果来看，双重卡压情况下神经的脆弱性增加。

Introduction : An experimental study to investigate the vulnerability of the sciatic nerve of rabbit in the double crush situation was performed.Materials and Methods : Adult rabbits, weighing approximately 3200g were animal models. The right sciatic nerve was exposed and bands of silicon tubes were placed on proximal and distal areas(double entrapment group ; group A)and only a proximal area(single proximal entrapment group ; group B) or distal area(single distal entrapment group ; group C). The diameter of the tubes were 2.0 mm in the proximal and 1.5 cm in the distal. After 6 to 12 weeks, evaluations of morphological findings, motor conduction velocity(MCV), and fast axonal flow using ^3H-Leucin were performed.Results : Macroscopically, small pseudoneuroma was seen just proximal to the band of proximal entrapment area in one rabbit and in distal area in one of three rabbits respectively in group A.A small pseudoneuroma was seen only in one each rabbit of three in group B and C respectively. Microscopically, demyelination was seen in all six entrapment areas of three rabbits in group A,and each of three entrapment areas of three rabbits in group B and C respectively. Degree of the demyelination was the most remarkable in distal entrapment area of group A,remarkable in proximal entrapment area of group A and weak to mild in group B and C.While MCV was delayd in all six entrapment areas of 3 rabbits in group A ; it was normal in each one of 3 rabbits in group B and C.Whereas, ^3H-Leucin elevated just proximal to all entrapment areas in group A,B and C,was elevated remarkably in both proximal and distal entrapment area of the rabbits in group A.Discussion : From the results of morphological and electrophysiological findings and evaluation of fast axonal flow, vulnerability of the nerve in a double entrapment situation increased.