Perineum Flashcards
Describe the boundaries of the anal triangle.
Below the pelvic diaphragm, it is the posterior component if a line is drawn across from the ischial tuberosities
What is the pectinate line?
It divides the lower third and upper two-thirds of the anal canal
Describe the arterial supply of the anal canal.
Above the pectinate line: Superior Rectal Artery
Below the pectinate line: Inferior Rectal Artery
Describe the venous drainage of the anal canal.
Above the pectinate line: Superior Rectal Vein
Below the pectinate line: Inferior Rectal Vein
Describe the innervation of the anal canal.
Somatic: Inferior Rectal Nerve
Autonomic: Inferior Hypogastric Plexus
External Anal Sphincter Innervation
Inferior Rectal Branch of Pudendal Nerve (S2-S4)
Internal Anal Sphincter Innervation
Inferior Hypogastric Plexus (smooth muscle)
What is the ischiorectoral fossa?
It is a fat filled space lateral to the anal triangle which is used as dead space for the anus to expand
What is the other name for the pudendal canal?
Alcock Canal
What are the boundaries of the pudendal canal?
It is formed by the fascia of the obturator internus
What does the pudendal canal connect?
It connects the lesser sciatic foramen to the posterior perineal membrane
What is the perineal body?
It lies at the front of the anal canal, and it is composed of interdigitating fibers of puboprostaticus/pubovaginalis, superficial external anal sphincter, and transverses perinea muscles.
What runs through the pudendal canal?
Pudendal Nerve
Internal Pudendal Artery
Internal Pudendal Nerve
What are the branches of the pudendal nerve?
Inferior Rectal Nerve
Perineal Nerve
Dorsal Nerve to Penis/Clitoris
What are the contributions of the pudendal nerve?
S2, S3 and S4
S2, 3 , 4 keeps the junk off the floor
What are the contributions of the sciatic nerve?
L4, L5, S1, S2 and S3
What is the significance of the pectinate line?
It marks the transition from the rectum to the anal canal
What is the recto-uterine pouch and what is its significance?
In females, the recto-uterine pouch is the lowest point of the peritoneal cavity and it is important because it is a site where infection and fluids can collect.
What are the other terms used for fallopian tube?
Oviduct
Uterine Tube
What does Scarpa’s fascia continue as in the perineum?
Colles’ Fascia
What two nerves the pudendal nerve divide into at the end of the anal triangle?
Perineal Nerve and the Dorsal Nerve of the Penis/Clitoris
What are the main branches of the internal pudendal artery?
Inferior Rectal Artery
Perineal Artery
Dorsal Artery of Penis/Clitoris
Where does the perineal artery come off of the pudendal artery?
It gives this branch off to the superior pouch and then continues to the deep pouch
What is the perineal membrane also known as?
Inferior Fascia of the Urogenital Diaphragm