Volume 1

Quain's elements of anatomy / edited by Edward Albert Schäfer and George Dancer Thane.

Date:
1895-1898
Catalogue details

Licence: Public Domain Mark

Credit: Quain's elements of anatomy / edited by Edward Albert Schäfer and George Dancer Thane. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    passes in nearly to the centre of the cord (posterior septum). Its position is marked, especially in the lumbar enlargement and in^llB Guivical region, by a superficial furrow. At its end is thepostei-ior^ovjre!/ commissure. Besides these two median fissures, a Tate'i-al fuirow is seen on each side of the cord, corresponding with the line of attachment of the posterior roots of the spinal nerves. It is named the postero-Meral groove (fig. 7, c, 4). Each lateral half of the cord is Fig. 7.—Different vikws of a portion Of THE SPINAL CORD FROM THE CERVICAL REGION WITH THE ROOTS OF THE NEKVES. Slightly enlarged. (Allen Thomson.) In A, the anterior or ventral surface of the specimen is shown, the anterior nerve-root of the right side having been divided ; in B, a view of the right side is given ; in C, the upper surface is shown; in D, the nerve-roots and ganglion are shown from below. 1, the anterior median fissure; 2, posterior median fissure; 3, antero-lateral impression, over which the bundles of the anterior nerve-root are seen to spread (this im- pression is too distinct in the figure) : 4, postero-lateral groove into which the bundles of the posterior root are seen to sink ; 5, anterior root; 5', in A, the anterior root divided and turned up wards ; 6, the posterior root, the fibres of which pass into the ganglion, 6'; 7, the united or compound nerve ; 7', the posterior primary branch, seen in A and i> to be derived in part from the ante- rior and in part from the posterior root. divided superficially by the postero-lateral groove into a posterior and an antero- lateral part. The attachment of the anterior roots, however, subdivides the latter into anterior and lateral portions. An antero-lateral groove has sometimes been described in the line of origin of the anterior roots of the nerves, but usually has no real existence. The fibres of these roots in fact, unlike the posterior, do not dip into the spinal cord in one narrow line, but spread over a space of some breadth. On the posterior surface of the cord, at least in the upper part, there is on each side of the middle line a slightly marked longitudinal furrow (tig. 11) situated about- one millimeter from the posterior median fissure, and marking off, in the cervical region, a slender tract, the postero-mesial column. This sulcus, which is better marked in some individuals than in others, is termed the posterior i)iter]n£dipte furroiv. An incomplete connective tissue septum {posterior intermediate septum) exteiids from the furrow into the white substance of the cordTThe larger rehiaining part of the posterior column is termed the postero-latei'al column. INTERNAL STRUCTURE OF THE SPINAL CORD; RELATIVE PROPORTIONS OF O-REY AND WHITE MATTER. Grey matter.—When the spinal cord is cut across (figs. 8,11,14) it is seen that the grey matter occupies the more central parts, being almost completely enclosed by the white matter. The grey matter appears in the form of two irregularly crescentic portions on either side, united across the middle line by the posterior grey commis- sure before mentioned, so that its section may be compared in shape to the letter H.