Expansion
Celiac trunk supplies foregut; SMA supplies midgut; IMA supplies hindgut
Mnemonic
Three divisions, each with its own artery, nerve supply and referred pain:
| Division | Extent | Artery | Referred pain |
|---|---|---|---|
| Foregut | Mouth to ampulla of Vater | Coeliac, T12 | Epigastrium |
| Midgut | Ampulla to two thirds along transverse colon | Superior mesenteric, L1 | Umbilical |
| Hindgut | Distal transverse colon to upper anal canal | Inferior mesenteric, L3 | Suprapubic |
“Epigastric, umbilical, suprapubic: top, middle, bottom.”
This is the anatomy behind the classic history of appendicitis: pain begins periumbilical, because the appendix is midgut and visceral pain refers to the midline, then shifts to the right iliac fossa once the inflamed appendix irritates the parietal peritoneum, which has somatic segmental innervation and localises precisely.
Learning note
- Foregut - coeliac trunk
- Midgut - superior mesenteric artery
- Hindgut - inferior mesenteric artery