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

Research Project

Project/Area Number	04670904
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Orthopaedic surgery
Research Institution	Department of Orthopaedic Surgery, School of Medicine, Iwate Medical University
Principal Investigator	NISHIDA Jun Research Instructor of Department of Orthopaedic Surgery, School of Medicine, Iwate Medical University, 医学部, 助手 (20198469)
Co-Investigator(Kenkyū-buntansha)	ABE Masataka Professor of Department of Orthopaedic Surgery, School of Medicine, Iwate Medica, 医学部, 教授 (70048271) FURUMACHI Katsuro Assistant Professor of Department of Orthopaedic Surgery, School of Medicine, Iw, 医学部, 講師 (90244920) TAJIMA Katsumi Research Instructor of Department of Orthopaedic Surgery, School of Medicine, Iw, 医学部, 助手 (80236520)
Project Period (FY)	1992 – 1993
Project Status	Completed (Fiscal Year 1993)
Budget Amount *help	¥2,000,000 (Direct Cost: ¥2,000,000) Fiscal Year 1993: ¥1,000,000 (Direct Cost: ¥1,000,000) Fiscal Year 1992: ¥1,000,000 (Direct Cost: ¥1,000,000)
Keywords	double crush syndrome / entrapment neuropathy / axonal flow / rabbit / ^3H-Leucin / sciatic nerve / animal model / mortor conduction velocity / 坐骨神経 / 重複性絞扼性神経症 / 形態学 / 電気生理学
Research Abstract	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.