Caecum and appendix
Organ supplied · Midgut T10
Midgut structures supplied solely by ileocolic branches — anterior and posterior caecal arteries and the appendicular artery, an end artery in the free edge of the mesoappendix.
Traced from the start
- Abdominal aorta
- Superior mesenteric artery
- Ileocolic artery
- Caecum and appendix
Detail
- Supply
- Anterior and posterior caecal and appendicular arteries (ileocolic, SMA)
- Appendix base
- Where the three taeniae coli converge, at McBurney's point on the surface
- Referred pain
- Periumbilical (T10 visceral) then right iliac fossa (somatic, parietal peritoneum) once the serosa is inflamed
When it goes wrong
Luminal obstruction (faecolith, lymphoid hyperplasia) → distension → appendicular artery thrombosis
Pain migrates from the periumbilical region (T10 visceral) to the right iliac fossa (somatic parietal peritoneum); gangrene and perforation follow because the end artery has no collaterals
Retrocaecal appendix (commonest position) inflamed away from the anterior parietal peritoneum
Little RIF tenderness or guarding; positive psoas sign and flank tenderness instead
Practise this structure
1 question in the bank tagged Appendix.