Rectal supply
fascial layers
- Upper 1/3 peritoneum to front and sides
- Middle 1/3 peritoneum to front only
- Lower 1/3 devoid of peritoneum
arterial ss
Branches of inferior mesenteric and internal iliac
superior/middle/inferior rectal artery (go figure)
venous drainagae
rectal veins
empty into portal venous system
one of the sites of portosystemic anastomosis
innervation
sympathetic innervation
- lumbar splanchnic nerves L1-3
- pass via superior and inferior hypogastric plexuses
parasympathetic innervation
S2-4 via the pelvic splanchnic nerves and inferior hypogastric plexuses
sensory
pain transmission follows parasympathetic fibres S2-4
lymphatic drainage
Upper rectum → pararectal lymph nodes → inferior mesenteric nodes
Below dentate line → superficial inguinal nodes
Lower part of rectum → internal iliac
