国人臂神经丛的类型

THE VARIATIONS OF THE BRACHIAL PLEXUSIN THE CHINESE

前言关于臂丛的研究,Kerr[1]对白种及有色人种曾统计175侧;Harris[2]解剖鱼类以上各种动物臂丛158例,但人的臂丛仅有30例,他只分前置(Pre-fixed type)及后置(post-fixedtype)二种类型。

248 brachial plexuses belonging to 124 Chinese bodies(24 adult male,45 male,and 55 femalechildren)were studied.According to the pattern of the arrangement of the roots of plexus,itcould be divided into prefix,postfix and intermediate types with an addition of seven subtypes(a,ab,c,cd,d,e,f).This variation when compared with that of Kerr,was found to be quite close.According to the longitudinal and transverse changes of the roots,trunks and cords these plexuscould be classified into 2 normal and 16 abnormal types.8 abnormal types was resulted from thevariations in the roots and another 8 types was due to the variation in the trunks or cords.Thelongitudinal changes of the roots,trunks and cords if classified according Kerr’s classification andcompared with his result,the number of the abnormal types is greater than his ones.If the trans-verse changes were also included,the difference would be still greater.Regarding the symetry of the plexuses when only prefix or postfix was considered the ratio be-tween the symetrical and asymetrical ones was 2:1 whereas that of Kerr was 3:2.When the longi-tudinal and transvrse changes were also included the ratio between symetrical and asymetrical oneswas 1:2.The symetrical type was not only found in the normal types as claimed by Kerr but alsofound in the abnormal types.