Descending colon

Descending colon
Descending colon
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Front of abdomen, showing surface markings for liver, stomach, and great intestine. (Descending colon visible at center right, in blue.)
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The duodenum and pancreas. (Descending colon visible at lower right.)
Latin colon descendens
Gray's subject #249 1181
Artery Left colic artery
Precursor Hindgut
MeSH Colon,+Descending

The descending colon of humans passes downward through the left hypochondrium 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 muscle, and then descends, in the angle between psoas and quadratus lumborum, to the crest of the ilium, where it ends in the sigmoid colon.

The peritoneum covers its anterior surface and sides, and therefore the descending colon is described as retroperitoneal. (The transverse colon and sigmoid colon, which are immediately proximal and distal, are intraperitoneal). Its posterior surface is connected by areolar tissue with the lower and lateral part of the left kidney, the aponeurotic origin of the transversus abdominis, and the quadratus lumborum.

It is smaller in caliber and more deeply placed than the ascending colon. It has a mesentery in 33% of people, and is therefore more frequently covered with peritoneum on its posterior surface than the ascending colon (which has a mesentery in 25% of people). However, it is less likely to undergo volvulus than the ascending colon.

In front of it are some coils of small intestine.

Additional images

External links


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Look at other dictionaries:

  • descending colon — n the part of the large intestine on the left side that extends from the bend below the spleen to the sigmoid colon compare ASCENDING COLON, TRANSVERSE COLON …   Medical dictionary

  • descending colon — noun the part of the large intestine that descends from the transverse colon to the sigmoid colon • Hypernyms: ↑colon • Part Holonyms: ↑large intestine …   Useful english dictionary

  • descending colon — noun A part of colon adjacent to sigmoid colon …   Wiktionary

  • descending colon — /koh leuhn/, Anat. the last portion of the colon, beginning at the upper left abdomen in the region of the spleen and continuing downward along the left posterior wall to the sigmoid flexure. See diag. under intestine. * * * …   Universalium

  • descending colon — descend′ing co′lon [[t]ˈkoʊ lən[/t]] n. anat. the last portion of the colon …   From formal English to slang

  • Colon (anatomy) — For other uses, see Colon. Colon (anatomy) Front of abdomen, showing surface markings for liver, stomach, and large intestine. Gray s …   Wikipedia

  • Colon — The part of the large intestine that runs from the cecum to the rectum as a long hollow tube that serves to remove water from digested food and let the remaining material, solid waste called stool, move through it to the rectum and leave the body …   Medical dictionary

  • colon — colon1 /koh leuhn/, n., pl. colons for 1, cola / leuh/ for 2. 1. the sign (:) used to mark a major division in a sentence, to indicate that what follows is an elaboration, summation, implication, etc., of what precedes; or to separate groups of… …   Universalium

  • Colón — /koh lon /; Sp. /kaw lawn /, n. a seaport in Panama at the Atlantic end of the Panama Canal. 85,600. * * * Segment that makes up most of the large intestine. Though the two terms are often used interchangeably, the colon technically excludes the… …   Universalium

  • colon descendens — [TA] descending colon the portion of the colon between the left colic flexure and the sigmoid colon at the pelvic brim; the part of it that lies in the left part of the iliac fossa is sometimes called the iliac colon …   Medical dictionary

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