Corpus: Descending colon

The descending colon is the part of the colon that lies between the left colonic flexure (flexura coli sinistra) and the sigmoid colon.

The descending colon runs caudally from the left hypochondriacal region through the lumbar region and passes the lateral edge of the left kidney. At the lower pole of the kidney, the organ swings slightly medially to the lateral edge of the psoas major muscle. It is followed by the descending colon as far as the iliac crest, where it merges into the sigmoid colon.

In contrast to the transverse and sigmoid colon, the descending colon is located secondarily retroperitoneally. Its posterior surface is connected to the kidney and the aponeuroses of the quadratus lumborum and transversus abdominis muscles via areolar connective tissue.

The organ cross-section of the descending colon is smaller than that of the ascending colon.

• Image source for podcast: © Amelia Speight / Unsplash