T1Q6 Perineum, Nerves

Question 1

Pudendal Nerve

Answer 1

*major (parent) somatic nerve of reigon
Origin: S2-S4
Course:
1. exits pelvic cavity (greater sciatic) 
2. passes around sacrospinous ligament
3. passes medially through less sciatic
4. pudendal canal of obturator muscle
* accompanied by pudendal arteries/ veins

Branches:
inferior rectal
perineal
dorsal nerve of penis/ clitoris

Question 2

pudendal canal

Answer 2

a tendonous sheath in the obturator muscle that houses pudendal neurovasculature

Question 3

inferior rectal nerve

Answer 3

origin: pudendal nerve (s2-S4, sacral plexus)
motor target: *external anal sphincter, leavtor ani muscles
sensory target: skin of anal triangle

Question 4

perineal nerve

Answer 4

origin: pudendal nerve (S2-S4, sacral plexus)
motor target: muscles of superficial and deep perineal pouches
sensory: gives rise to posterior scrotal/ labial nerve

Question 5

posterior scrotal/ labial nerve

Answer 5

the largest sensory branch of the perineal nerve

Question 6

visceral nerve course: skin

Answer 6

course: postganglionic branches of the sympathetic trunk join the anterior rami of sacral spinal nerves at gray rami communicantes
clinical: dryness?

Question 7

visceral nerve course: erectile tissue

Answer 7

inferior hypogastric plexus, parasympathetic fibers, from spinal chord levels S2 to S4