The transverse colon is the longest and most mobile part of the large intestine. It measures up to 45 cm in length.
The transverse colon is the continuation of the ascending colon from the right colic flexure. It passes from the right to left hypochondrium in a downward convex path crossing both the epigastric and umbilical zones. In the left hypochondrium, it curves sharply on itself beneath the lower end of the spleen, forming the left colic flexure where it continues as the descending colon.
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. The gastrocolic ligament also attaches the transverse colon to the stomach. The phrenicocolic ligament attaches to the left colic flexure and connects it to the diaphragm, with variable connection to the inferior aspect of the spleen.
- superiorly (right to left): liver, gallbladder, greater curvature of the stomach, spleen
- inferiorly: small bowel
- anteriorly: greater omentum and anterior abdominal wall
- posteriorly (right to left): 2nd part duodenum, head and body of pancreas, small bowel
- superior mesenteric plexus
- inferior mesenteric plexus
- parasympathetic: derived from pelvic splanchnic nerves (S2-S4)
Lymphatics accompany vessels and drain to paracolic nodes, and to the superior mesenteric group (proximal two-thirds) and inferior mesenteric group (distal two-thirds).
Double contrast barium enemas provided good anatomical detail from the rectum to the cecum. The patient may need to be rolled into various positions to get the barium to coat the lumen of the colon.