脊髓运动神经元功能性再生与侧方入路臂丛前根再植入术:解剖学特征

Functional regeneration of motor neurons in the spinal cord and the reimplanta tion of avulsed branchial plexus ventral roots through lateral approach:anatomic al characteristics

目的:根性撕脱的脊神经根再植入脊髓后,脊髓灰质前角的运动神经元可产生功能性的再生,观察臂丛根部及椎管内解剖学结构,探讨臂丛神经前根再植入脊髓的最佳解剖入路。方法:实验于2002-06/2003-05在哈尔滨医科大学附属第一医院显微外科实验室完成。成人颈胸段尸体标本19例,男16例,女3例。在15例30侧成人颈胸段尸体标本上,对臂丛各神经根直径,出椎间孔处与椎体纵轴向头侧方向的夹角,各椎间孔(C4～5～T1～2)高和宽,椎管内各神经根分出角和长度、脊髓半径、前根起始处至脊髓中线距离,前根长度以及各脊髓节段与对应椎间盘的相对位置进行形态学观测。根据以上测量结果,另4例标本采用侧方入路行臂丛前根再植入术,寻找侧方入路再植入最佳位点。结果:椎管外臂丛各神经根夹角C5(138±7)°,T1(83±13)°,脊髓半径C5(7.8±0.4)mm,T1(6.0±0.4)mm,臂丛前根起始处至脊髓中线距离C5(3.8±0.3)mm,C8(2.8±0.4)mm,均由上至下逐渐减小。各椎间孔高、宽C4～C5分别为(7.3±1.2),(5.6±1.3)mm,T1～T2分别为(10.5±0.6),(7.5±0.8)mm,椎管内臂丛各神经根长度C5(15.1±1.4)mm,T1(19.2±2.6)mm,分出角C5(90±3)°,T1(125±8)°,神经前根长度C5(9.9±1.5)mm,T1(15.6±2.9)mm,均由上至下逐渐增大。C5～7脊髓节对应C3～4,C4～5。

AIM:The motoneuron in ventral gray horn can induce functional regeneration aft er the avulsed brachial plexus ventral roots were reimplanted into the spinal co rd.The aim of this paper is to observe the anatomical structure of roots in brac hial plexus and inner vertebral canal,and investigate the optimal anatomical app roach to reimplanting avulsed brachial plexus ventral roots into the spinal cord . METHODS:The experiment was done in the microsurgery laboratory of the First Af filiated Hospital of Harbin Medical University from June 2002 to May 2003.Ninete en specimens from cervicothoracic spine of adult cadavers(16 males and 3 males) were chosen for the experiment.Fifteen of the 30 cervicothoracic spine specimens were used to morphologically measure and observe the diameter of brachial plexu s roots,and the included angle between intervertebral foramina and head sides of longitudinal axis in vertebral body,the height and the width of intervertebral foramina(C4-5 to T1-2),the diverge angle and the length of brachial plexus roo ts inside vertebral canal,the radius of spinal cord,the distance from the origin ation of ventral roots to the midline of spinal cord,the length of ventral roots ,and the relative position between spinal cord segments and their corresponding intervertebral discs.Another four specimens were reimplanted with the brachial p lexus ventral roots into spinal cord by the lateral approach in order to locate the most proper point for reimplantation by lateral approach. RESULTS:The included angle of brachial plexus roots were (138±7)°for C5 spin al cord segment and (83±13)°for T1 spinal segment,the radius of spinal cord we re (7.8±0.4) mm for C5 and (6.0±0.4) mm for T1,and the distance from the origi nation of ventral roots to the midline of spinal cord were (3.8 ±0.3) mm for C5 and (2.8±0.4) mm for C8.From up to down,all the data decreased gradually.The h eight and the width of intervertebral foramina were (7.3±1.2) mm,(5.6±1.3) mm for C4 to C5,and (10.5±0.6) mm,(7.5±0.8) mm for T1 to T2,the diverge angle and the length of brachial plexus roots inside vertebral canal were (90±3)°,( 15. 1±1.4) mm for C5 and (125±8)°,(19.2±2.6) mm for T1,and the length of ventral roots was (9.9±1.5) mm for C5,(15.6±2.9) mm for T1.From up to down,the data i ncreased gradually.C5-7 spinal cord segments faced C3-4,C4-5,C5-6 vertebral discs,and C8,T1 spinal cord segments faced C6,C7 vertebrae respectively.The best position for reimplantation by lateral approach should be located at 4 mm insid e outer margin of spinal cord. CONCLUSION:The best position of reimplanting the avulsed brachial plexus ventr al roots into spinal cord is located inside outer margin of the corresponding sp inal cord segments;The brachial plexus ventral roots can be reimplanted into the best position by lateral approach,which will make the outcomes of functional re covery more satisfactory.