Henry Gray (18251861). Anatomy of the Human Body. 1918.
lower than the main curve. It is almost completely invested by peritoneum, and is connected to the inferior border of the pancreas by a large and wide duplicature of that membrane, the transverse mesocolon. It is in relation, by its upper surface, with the liver and gall-bladder, the greater curvature of the stomach, and the lower end of the spleen; by its under surface, with the small intestine; by its anterior surface, with the anterior layers of the greater omentum and the abdominal parietes; its posterior surface is in relation from right to left with the descending portion of the duodenum, the head of the pancreas, and some of the convolutions of the jejunum and ileum.
The left colic or splenic flexure(Fig. 1056) is situated at the junction of the transverse and descending parts of the colon, and is in relation with the lower end of the spleen and the tail of the pancreas; the flexure is so acute that the end of the transverse colon usually lies in contact with the front of the descending colon. It lies at a higher level than, and on a plane posterior to, the right colic flexure, and is attached to the diaphragm, opposite the tenth and eleventh ribs, by a peritoneal fold, named the phrenicocolic ligament, which assists in supporting the lower end of the spleen (see page 1158).
FIG. 1076 Iliac colon, sigmoid or pelvic colon, and rectum seen from the front, after removal of pubic bones and bladder. (See enlarged image)
The Descending Colon1 (colon descendens) passes downward through the left hypochondriac and lumbar regions along the lateral border of the left kidney. At the lower end of the kidney it turns medialward toward the lateral border of the Psoas, and then descends, in the angle between Psoas and Quadratus lumborum, to the crest of the ilium, where it ends in the iliac colon. The peritoneum covers its anterior surface and sides, while its posterior surface is connected by areolar tissue with the lower and lateral part of the left kidney, the aponeurotic origin of
Note 1. In the Basle nomenclature the descending colon is the portion between the left colic flexure and the superior aperture of the lesser pelvis; it is, however, convenient to describe its lowest part as the iliac colon. [back]