Male and Female Perineum

Question 1

Abdominal Aorta we have what coming off? Male vs female?

in the female, what does it split to?

there’s one more that comes off the aorta.

Answer 1

Gonadal artery –> testicular or ovarian artery if there’s a penis or not.

it heads down and travels as part of the spermatic cord, supplies the testes.

in females, it does not go through inguinal canal, instead goes toward the uterine tube near the ovary and supplies the ovary –> it supplies this through tubal and ovarian branches.

Median Sacral Artery.

Question 2

Terminal branch of the IMA is what?

Answer 2

Superior Rectal A.

Question 3

Aorta splits to what?

Answer 3

common iliac artery

the common iliac arteries don’t do anything, but then split into their terminal branches –> External and Internal Iliac A.

External is destined to become the femoral artery after it travels under the inguinal ligament.

Internal iliac Artery

Question 4

Internal Iliac Artery?

Answer 4

Internal has an anterior and posterior division.

you need to think of the branches coming off of the anterior or posterior division.

Question 5

Anterior Division of the Iliac Artery (women)?

Answer 5

first branch: Umbilical Artery
2nd branch = Obturator Artery.
3rd = uterine artery (female) or inferior vesical artery (male)
4th = vaginal artery
5th = Middle Rectal A.
terminal = inferior gluteal A and Internal Pudendal A.

Question 6

Umbilical Artery?

branches?

what does it become?

Answer 6

used to communicate with the maternal blood, should have dried up, but it makes some additional vessels which supply the urinary bladder. so the proximal most part of the vessel remains intact.

makes Superior Vesical Arteries, and then becomes the Medial Umbilical Ligament which goes to the umbilicus, is covered in peritoneum where it becomes the medial umbilical fold

Question 7

Obturator A?

Answer 7

artery goes to the medial thigh and does medial thigh stuff

it follows the obturator N!

Question 8

Uterine artery?

Answer 8

this is the 3rd branch coming off of the anterior division of the iliac artery

it does have branches –> tubal branch going to the uterine tube, and an ovarian branch which goes to the ovary. also has a vaginal branch.

the main branch goes to the uterus itself.

Question 9

In females it’s called the uterine artery, what is it called in males and where is it going?

Answer 9

it’s heading to the posterior aspect of the urinary bladder.

inferior vesical artery

Question 10

Vaginal A?

Answer 10

this is the 4th branch, and is different than the vaginal branch of the uterine a., and it goes to the vagina.

Question 11

Middle Rectal A.

Answer 11

5th branch of the anterior division of the internal iliac. supplies the middle rectum

Question 12

Terminal branches of the anterior division of the internal iliac artery?

Answer 12

inferior gluteal A. –> it come below the piriformis, goes to a bunch of muscles.

Internal Pudendal. –> goes out through the lesser sciatic foramen, over the sacrospinous ligament and back into the perineum through the lesser sciatic foramen and jumps right into the pudendal canal.

Question 13

the tubal branch of the uterine A. forms an anastomoses with what?

what about the ovarian branch from the Uterine A?

Answer 13

tubal branches from the ovarian A. (comes off of the abdominal Aorta)

ovarian branches from the ovarian A. (comes off the abdominal aorta remember)

Question 14

How do you tell the difference between inferior gluteal and internal pudendal A on the cadaver?

Answer 14

gluteal usually more posterior which makes sense because its heading posteriorly

internal pudendal is more anterior as it heads out of your view. it pops back in to the pudendal canal.

Question 15

water under the bridge?

Answer 15

the uterine artery travels over the ureter.

Question 16

What does the internal pudendal A give off and when does it give it off?

Answer 16

it goes under the sacrospinous ligament, then immediately into the pudendal canal and gives off the inferior rectal A.

then it makes a perineal artery, which changes names to posterior labial A. where it heads to the labia majora.

it then makes an artery to the vaginal vestibule

then it travels to the clitoris where it splits to its terminal branches –> Deep and dorsal artery of the clitoris.

Question 17

Difference between the deep and dorsal artery of the clitoris?

Answer 17

deep goes right into the erectile tissue, dorsal is on the dorsal side of the clitoris.

Question 18

Any changes to the anterior division of the internal iliac A. for men? What does it make?

Answer 18

Instead of a uterine artery, it’s an inferior vesical artery, where it heads to the posterior aspect of the urinary bladder

before it gets there, it makes a small artery called the
“Artery to the ductus deferens” and a “prostatic branch” to the prostate

Question 19

Where does the Artery to the ductus deferens go? (2 spots)

Answer 19

Ductus deferens goes to the ductus deferens but also goes through the spermatic cord through the inguinal canal.

Question 20

What changes happen for the internal pudendal in the male?

Answer 20

very very similar

still give off the inferior rectal..

then a perineal artery, but instead of continuing on, it changes names to the Posterior Scrotal A. and supplies the scrotum.

Artery to the bulb of the penis

then a deep and dorsal artery of the penis

Question 21

Deep and dorsal artery of the penis difference?

Answer 21

Deep is going right through the middle of the corpus cavernosum

Dorsal runs along the top of the corpus cavernosum.

Question 22

Posterior division of the Internal iliac?

Answer 22

Iliolumbar A.

Lateral Sacral a.

superior gluteal A.

Question 23

Iliolumbar A?

Answer 23

1st branch of the posterior division of the internal iliac

has a spinal branch which does the whole spinal branch thing. it’s the only vessel that goes back to where the arteries came from (going superiorly)

splits to the Iliac Branch of the iliolumbar A.

Question 24

Lateral Sacral A.

Answer 24

2nd branch of the posterior division of the internal iliac

sends multiple branches into the anterior sacral foramina.

Question 25

Superior Gluteal A?

Answer 25

third branch of the posterior division of the internal iliac

it very quickly goes over the piraformis, out through the greater sciatic foramen, supplies gluteal muscles

Question 26

Superior Rectal A comes from where?

Middle Rectal A comes from where?

Inferior Rectal A comes from where?

Answer 26

Inferior Mesenteric A..

Anterior Division of the Internal Iliac A.

Internal Pudendal A.

Question 27

Rectal Venous Plexuses?

Answer 27

internal and external venous plexus that are drained by the corresponding rectal veins.. superior, middle, and inferior rectal veins drain the internal and external venous plexuses.

Question 28

Internal and External Hemorrhoids?

how do you know the difference?

what would someone present with to know?

Answer 28

Sometimes these veins (rectal venous plexuses) prolapse, lumen gets too big for the valves to work, they pool blood.

if it happens in the internal venous plexus = internal hemorrhoid = not painful

Bright red blood and not painful? internal

Blood with pain, itchy? external hemorrhoid

Question 29

Lymphatics? (8)

Answer 29

lateral aortic or lumbar lymph nodes

Inferior mesenteric (at the stump of the IMA)

common iliac

Internal and external iliac

Sacrum

Deep inguinal lymph nodes

pararectal lymph nodes

Superficial inguinal lymph nodes

Question 30

4 nerves in the abdomen that we’ll see in the pelvis too?

Answer 30

Ilioinguinal becomes part of the contents of the spermatic cord

Genital Branch of the geniofemoral N. (same thing as ilioinguinal)

lumbosacral trunk and obturator are going to be super easy to see in the pelvis.

Question 31

What’s to note about counting anterior rami of the lumbosacral trunk?

Answer 31

the trick with the lumbosacral trunk…

not counting that as the anterior ramus of the first sacrospinal nerve.

Question 32

What are the spinal segments of the sacral plexus?

what about S5?

Sciatic?

Answer 32

We send the lumbosacral trunk down into the sacral plexus.

so it’s L4 all the way down through S4

S5 joins with the coccygeal nerve to make the least interesting plexus = coccygeal plexus (it innervated the levator ani)

L4 to S3 NOT 4

Question 33

What are all the nerves of the sacral plexus?

Answer 33

Superior Gluteal Nerve and Inferior gluteal nerve are carrying 3 levels

Superior = highest 3 levels it can possibly be carrying.. L4, L5, S1

Inferior = one whole step down… L5, S1, S2

Nerve to the obturator internus and Nerve to the quadratus femorus. –> you’d think that obturator internus (since it’s higher) it would carry the higher nerve than quadratus, but it’s flipped!

Quadratus femorus = same as superior gluteal.. L4-S1

Nerve to the Obturator Internus = same as inferior… L5-S2

Nerve to the Piraformis = just S1, S2.. no lumbar!

posterior femoral cutaneous (posterior thigh innervation) –> carrying S1 - S3

Perforating cutaneous branches (S2,3)

Pudendal Nerve –> S2, S3, S4

Question 34

Pudendal Nerve spinal levels?

mnemonic?

Answer 34

S2 3 4, keeps your penis off the floor.

Question 35

Superior and inferior gluteal nerve spinal levels?

Answer 35

Superior = highest 3 levels it can possibly be carrying.. L4, L5, S1

Inferior = one whole step down… L5, S1, S2

Question 36

Nerve to the obturator internus and nerve to the quadratus femorus spinal levels?

Answer 36

Nerve to the obturator internus and Nerve to the quadratus femorus. –> you’d think that obturator internus (since it’s higher) it would carry the higher nerve than quadratus, but it’s flipped!

Quadratus femorus = same as superior gluteal.. L4, L5, S1

Nerve to the Obturator Internus = same as inferior… L5, S1, S2

Question 37

Nerve to the piraformis spinal levels?

posterior femoral cutaneous spinal levels?

Answer 37

Nerve to the Piraformis = just S1, S2.. no lumbar!

posterior femoral cutaneous (posterior thigh innervation) –> carrying S1 - S3

Question 38

What’s to note about the pudendal N?

what’s the difference between this and the artery?

Answer 38

There is an internal pudendal A but the nerve is just Pudendal N.

DO NOT ADD INTERNAL TO PUDENDAL N.

Question 39

branches of the pudendal N?

Answer 39

first branch = inferior rectal n. –> goes to the external anal sphincter muscle and anal canal.. runs with the inferior rectal A.

then we’re going to make superficial and deep perineal nerves. (the pudendal nerve is still continuing on until you get to the erectile tissue.

if you see one of the branches going to muscle, it is deep perineal nerves.. if it is not, it’s superficial (skin or nothing)

superficial becomes posterior labial or posterior scrotal nerves

deeps are going to all those muscles that we said were called “deep perineal nerves
“

Question 40

what happens when the pudendal nerve continues on towards the genitals?

Answer 40

it innervates the external urethral sphincter muscle… (remember, that one oddball that isn’t innervated by deep?)

it’ll also run to the dorsal of the penis or clitoris.

dorsal nerve of the penis, dorsal nerve of the clitoris

Question 41

Sympathetic division is what nerves?

Answer 41

thoracolumbar

Question 42

Pre

Answer 42

if we want to send sympathetics to the genitals, we have to come out of our own levels paravertebral ganglion and go down.

Question 43

Pathway of sympathetic presence in the pelvis?

1) how did we get sympathetic in?

Answer 43

In using option 3, we are going to come out via lumbar splanchnic nerves to inferior mesenteric ganglion.

Lumbar sympathetic trunk –> lumbar splanchnic nerves –> inferior mesenteric ganglion –> makes the inferior mesenteric plexus –> feeds into the superior hypogastric plexus –> feeds into inferior hypogastric plexus

Question 44

What is the parasympathetic division?

Answer 44

Craniosacral

Question 45

what is the big player in the parasympathetic division?

where is the presynaptic cell body for these?

how do they get to here?

what happens once they get to their area?

Answer 45

pelvic splanchnic nerves –> PARAsympathetic

the sacral part of the spinal cord. this is found in L2 or L3. that’s where the presynaptic cell bodies exist.

they run with the anterior rami of sacral spinal nerves to get here.

then they poke their heads out of the anterior sacral foramina as “pelvic splanchnic nerves”.. and these are feeding into the inferior hypogastric plexus.

Question 46

What are the two nerves found in the sacral portion of the pelvis?

Answer 46

Pelvic Splanchnic nerves -> parasympathetic

Sacral spinal nerves –> sympathetic!

Question 47

Pelvic Autonomic Plexuses:

1) inter mesenteric plexus

Answer 47

it’s a conduit… this is how we’re transferring sympathetic and parasympathetic from the superior mesenteric plexus down to the inferior mesenteric plexus by this inter mesenteric plexus

the problem is in that region the testicular/ovarian artery comes off from that region.. so they send branches to follow those arteries to get to the gonads.

Question 48

Pelvic Autonomic Plexuses:

1) Superior Hypogastric plexus

Answer 48

It is NOT MIXED.

this is all sympathetics.. there’s no sympathetics.

it gets it from the inter mesenteric plexus and sympathetic branches coming from the lumbar part of the sympathetic trunk as lumbar splanchnic nerves (these are going into the inter mesenteric plexus to synapse on the SHP)

Question 49

Pelvic Autonomic Plexuses:

1) Hypogastric nerves?

Answer 49

the superior hypogastric plexus is going to simplify into paired hypogastric nerves..

these.. because they’re coming out of the superior hypogastric plexus.. are ALSO JUST SYMPATHETIC… they’re conveying their information to the INFERIOR hypogastric plexus.

so that’s how we get sympathetic into the inferior

Question 50

Pelvic Autonomic Plexuses:

1) Inferior Hypogastric plexus

Answer 50

extremely important for pelvis!… so much so it’s called the pelvic plexus

it’s mixed. we’re putting sympathetics in through the hypogastric nerves

parasympathetics from pelvic splanchnic nerves.

Question 51

Pelvic Autonomic Plexuses in the Female?

Ovarian (periarterial plexus):

Answer 51

coming out of the inter mesenteric plexus..

it’s doing this because it’s following the ovarian artery that’s coming off the same spot of the aorta.

Question 52

Pelvic Autonomic Plexuses in the Female?

Vesical Plexus?

Answer 52

from the inferior hypogastric plexus

innervates external and internal urethral sphincter muscles and detrusor muscles

Question 53

Pelvic Autonomic Plexuses in the Female?

Uterovaginal plexus?

Answer 53

from the inferior hypogastric plexus

innervate the uterus and vagina

Question 54

Pelvic Autonomic Plexuses in the Female?

Cavernous nerves?

Answer 54

from the inferior hypogastric plexus

they come out of the uterovaginal plexus, but they’re only PARASYMPATHETIC NERVES.

they go to the vestibular glands (greater and lesser) and Erectile tissue.

Question 55

Pelvic Autonomic Plexuses in the Male?

Testicular Plexus

Answer 55

same as ovarian plexus in females, coming from inter mesenteric

Question 56

Pelvic Autonomic Plexuses in the Male?

vesical Plexus

Answer 56

We still have this in males.. it’s doing the same thing, innervating the internal and external urethral sphincter muscles and the detrusor muscle

Question 57

Pelvic Autonomic Plexuses in the Male?

Prostatic Plexus

Answer 57

This is going to innervate the prostate gland, proximal urethra, ductus deferens, seminal vesicles, ejaculatory ducts

WITH BOTH SYMPATHETIC AND PARASYMPATHETIC

Question 58

Pelvic Autonomic Plexuses in the Male?

Cavernous Nerves?

Answer 58

ONLY carry parasympathetic..

this goes to the 3 cylinders that make up the penis!

Question 59

Difference between Rami communicants, pelvic and sacral splanchnic nerves?

Answer 59

Rami Communicants are taking nerves from the sacral sympathetic trunk and shoving them into the anterior rami of sacral spinal nerves to innervate the body

Sacral Splanchnic nerves are coming out of the sacral sympathetic trunk and putting them into the inferior hypogastric plexus

Pelvic splanchnic (parasympathetic) are coming out of the anterior rami of sacral spinal N. to feed into the inferior hypogastric plexus.

Question 60

What feeds into the inferior hypogastric plexus (include both SNS and PNS)

Answer 60

Hypogastric N. from superior hypogastric plexus (SNS)

Sacral Splanchnic nerves from the sacral sympathetic trunk.

Pelvic Splanchnic N from the anterior rami of sacral spinal N.

Question 61

How is our body sending sympathetic signals to our entire body from the sacral sympathetic trunk?

Answer 61

dumping rami communicants into the anterior rami of sacral spinal N.