Week 2: Pelvis bones and pudendal nerve

Question 1

Pudendal nerve and its branches

Answer 1

• arises from S2,3,4. Body wall nerve with no parasympathetics
• Inferior rectal branches off first: sensory/motor to anal triangle
• perineal branch: divides into motor branches (SM,SS, symp/post), innervates muscles of UG triangle. And posterior scrotal/labial nerve (SS, Symp/post), innervates sensory to UG triangle.
• dorsal nerve of penis/clitoris (SS, Symp/post): sensory to penis or clitoris

Question 2

Greater and lesser sciatic foramen

Answer 2

• greater sciatic foramen: doorway between pelvic cavity and gluteal region
• lesser sciatic foramen: doorway between perineum and gluteal region