Ligament
Sigmoid mesocolon
The vascular attachment of the sigmoid loop
High-yield
The root bends near the left common iliac bifurcation; the left ureter passes behind this region.
Overview
Two peritoneal layers connect the sigmoid colon to the posterior abdominal and pelvic walls. Between them travel vessels, lymphatics, nerves and fat. A longer mesocolon allows a wider range of bowel positions without changing the fixed root.
Reference facts
- Attachments
- The root typically forms an inverted V: a lateral limb follows the left iliac region and a medial limb descends toward the sacrum. The apex overlies the iliac bifurcation and ureter.
- Function
- Supports a mobile colonic loop and conveys sigmoid vessels and the superior rectal vascular continuation, with lymphatics and nerves.
- Clinical point
- A long loop with a narrow attachment is susceptible to volvulus. The intersigmoid recess may trap small bowel, while the nearby ureter explains a risk of injury during sigmoid mobilization.
Frequently asked questions
Where does the sigmoid mesocolon attach?
The root typically forms an inverted V: a lateral limb follows the left iliac region and a medial limb descends toward the sacrum. The apex overlies the iliac bifurcation and ureter.
What does the sigmoid mesocolon do?
Supports a mobile colonic loop and conveys sigmoid vessels and the superior rectal vascular continuation, with lymphatics and nerves.
Why does the sigmoid mesocolon matter clinically?
A long loop with a narrow attachment is susceptible to volvulus. The intersigmoid recess may trap small bowel, while the nearby ureter explains a risk of injury during sigmoid mobilization.