Nerves of the pelvis Flashcards
Where does the pudendal nerve arise from?
Ventral rami S2 S3 S4
What are the branches of the pudendal nerve?
inferior rectal nerve
perineal nerves
dorsal nerve of penis/clitoris
Action of pudendal nerve
Sensation of labia clitoris penis scrotum anal canal
afferent sensation for erection
Motor function of external anal and urethral sphincters
Course of the pudendal nerve
ventral rami S2 S3 S4 > lesser sciatic foramen > greater sciatic foramen > joins internal pudenal artery and vein in pudendal canal and branches to form inferior rectal nerve, perineal nerve and dorsal nerve of penis/clitoris
Where does the perineal nerve arise from?
Pudendal nerve (ventral rami S2 3 4)
What are the branches of the perineal nerve?
superficial and deep
What does the perineal nerve supply?
superficial - supplies the posterior scrotal/labial nerves
deep perineal - supplies muscles - superficial transverse perineal muscle, bulbospongiosus, ischiocavernosus, and corpus cavernosus and Sphincter urethræ.
What does the inferior rectal nerve supply?
motor supply - external anal sphincter
sensation - anal canal to pectinate line
Where does the inferior rectal nerve arise from?
ventral rami S 2 3 4 > pudendal nerve > inferior rectal nerve
Where does the ilioinguinal nerve arise from?
from L1 anterior ramus
What does the ilioinguinal nerve innervate?
sensation for medial thigh
anterior labia and clitoris
anterior scrotum and root of the penis
What route does the ilioinguinal nerve take?
L1 - iliohypogatric> ilioinguinal > inguinal canal
Innervation of the anal sphincter
S4
internal anal - splachnic nerves
external anal - inferior rectal nerve + perineal nerve
Origin of anterior labial and anterior scrotal nerves
ilioinguinal nerve
Origin of posterior labial and posterior scrotal nerves
s2-4> pudendal nerve>perineal nerve> posterior labial/scrotal nerves
