Sigmoid colon
Organ supplied · Hindgut T12–L2
Intraperitoneal hindgut loop on a long mesocolon, supplied by the 2–4 sigmoid arteries. The arcade between the last sigmoid artery and the superior rectal artery is often incomplete — Sudeck's point at the rectosigmoid — the second colonic watershed.
Traced from the start
Detail
- Supply
- Sigmoid arteries (IMA) through the marginal artery
- Weak point
- Sudeck's point at the rectosigmoid junction
- Referred pain
- Suprapubic and left iliac fossa, T12–L2
When it goes wrong
IMA ligated at open AAA repair or covered by an endograft with a poor marginal artery
Sigmoid ischaemic colitis on days 1–3: bloody diarrhoea, left-sided pain, rising lactate; flexible sigmoidoscopy confirms; transmural necrosis carries high mortality
Sigmoid diverticulitis: inflamed diverticulum irritating parietal peritoneum
Left iliac fossa pain and tenderness with fever — 'left-sided appendicitis'; perforation gives generalised peritonitis
Practise this structure
1 question in the bank tagged Hindgut.