perineum Flashcards
where is the perineum?
inferior to the pelvic floor, btw lower limbs.
Includes soft tissue inferior to pelvic floor, ending at the skin
What are the two hiatuses on the pelvic floor?
urogenital hiatus and rectal hiatus
which hiatus on the pelvic floor is more towards the front of the body?
urogenital hiatus
Which hiatus on the pelvic floor is more towards the back of the body
the rectal hiatus
which muscle makes up the urogenital hiatus?
levator ani
Which muscle makes up the rectal hiatus?
lecvator ani
which posterior muscle of the pelvic floor is more lateral?
piriformis
Which posterior muscle of the pelvic floor is more medial
coccygeus
what is the anterior norder of the perineum?
pubic symphysis
What is the posterior border of the perineum?
coccyx/sacrum
What connects the pubic symphysis to the ischial tuberosity?
ishiopubic ramus
What is the lateral border o the perineum?
ischial tuberosity
What are the two triangles of the perineum?
urogenital triangle and anal triangle
Which triangle of the periteum is more anterior?
urogenital
what is the urogenital triangle bounded by?
anteriorly - pubic symphysis
laterally - ischial tuberosities
what is the anal triangle bounded by?
ischialn tuberosities and the coccyx
what does the scrotum have?
testes, epidemus, external spermadic cord
what is the bulb of the penis?
single erectile cylander, most proximal part of the penis
what is the crus of the penis?
have 2
“legs of the penis”
surrounds the bulb
What is the corpus spongiosum of the penis?
expansion o the bulb of the penis into the body of the penis. surrounding by the corpus cavernosum
what is the corpus cavernosum?
an expansion of the crus
what is the gland of the penis?
expansion of the corpus callosum. Secretions are expiled here
What makes up the body of the penis?
glans, corpus cavernosum, corpus spongiosum
What makes up the root of the penis?
crus and the bulb
where is the deep penile artery?
within the corpus cavernosum
where is the urethra?
within corpus spongisum
the bladder is ___ to the prostate (positionally)
superior
Where is the prostatic urethra?
within prostate
What is the urethra called when it exits the prostate and before it enters the penis?
membranous urethra
what structure houses the urethra?
corpus spongiosum
what is the urethra called once it enters the penis?
spongy urethra
where does urethra terminate?
external urethral orifice
what is the mons pubis?
fatty tissue that covers most of the external female genitalia`
what protects the external female genitalia
mons pubis
what is the prepuse of the clitoris?
tissue that protects the clitoris from the outside world, superficial to the clitoris
what is the labia majora?
outer lip of the vagina. made of fatty tissue. cushions the region
what is the labia minora?
inner lip of the vagina that protects and lubricates it
what is the pudendal cleft?
space btw the labia majora and minora
what is the anterior border of the female genitalia vestibule?
clitoris
What is the lateral border of the female genitalia vestibule?
labia minora
What is the posterior border of the female genitalia vestibule?
fourchette
what is the fourchette of the female genitalia vestibule?
tissue stucture at posterior border of the female genitalia vestibule
what is the function of the external urethral orifice?
urethra exits here
what is vaginal orifice?
opening of the vagina
What is the bulb of the vestibule?
part of female clitoris - becomes engorged with blood during arousal
what are the greater vestibular glands?
part of the clitorus, function is to lubricate the vagina
the glands for the clitoris are ___ to the clitoris
distal
What does the external urethral sphincter do?
surrounds entire urethra - applies pressure and compression to the urethra
What is the urethrocaginal sphincter?
structure that surronds the urethra and vagina
What is the compressor urethrae?
structure that surrounds anterior urethra and applies pressure to the urethra
superficial to deep what is the order of the urogenital triangle
skin, perineal fascia, superficial perineal pouch, perineal membrane, deep perineal pouch, then pelvic floor
what is the deep perineal pouch?
btw pelvic floor superiorly and perineal membrane inferiorly. Lies superior to perineal membrane. Forms the external urethral shincter
what makes up the deep perineal pouch in males?
deep transverse perineal muscle and external urethral sphincter
what is deep transverse perineal muscle?
muscle in the deep perineal pouch, supports the perineal region
what makes up the deep perineal pouch in females?
external urethral sphincter, urethrovaginal sphincter, compressor urethrae, deep transverse perineal muscle
what is the difference in the perineal pouch btw males and females
males do not have external urethral spincter or the compressor urethrae
where is the superficial perineal pouch?
btw perineal membrane superiorly and deep perineal fascia inferiorly. lies inferior to perineal membrane
what is the superior limit of the superficial perineal pouch
perineal membrane
what is the inferior limit of the superficial perineal pouch
colle’s fascia
what does the bulbospongiosus do
compresses bulb of penis during erection
what structures are in the male and female superficial perineal pouch?
bulbospongiosus, ischiocarvernosus, superficial transverse perineal muscle
what is the ischiocervernosus
compresses crus of the penis/clitorus during erection
what does the superficial transverse perineal muscle do?
support the perineal body
what is the superficial layer of the perineal fascia?
the superficial layer is continous with camper’s fascia of the anterior abdominal wall
What is the deep layer of the perineal fascia
layer that is continuous with scarpa’s fascia of the anterior abdominal wall (colle’s fascia)
what is the perineal body?
convergence/interlacing of bulbospongiosus, superficial perineal muscles, external anal sphincter, pelvic floor muscles
what is the anal triangle?
posterior portion of the perineum - has no perineal membrane!
What is the anal triangle bounded by
laterally - ischial tuberosities
posteriorly - coccyx
what 4 things does the anal triangle contain?
anal aperture, external anal sphincter, ischiorectal fossa, pudendal canal
what is the ischiorectal fossa
space filled with fat and important neurovasculature within the pudendal canal
what are the lateral and medial borders of the ischiorectal fossa?
lateral: obturator inernus
medial: external anal sphincter
What are the superior and inferior borders of the ischiorectal fossa?
superior: levator ani
inferior: perineal fascia
where is the pudendal canal/
in the ischiorectal fossa
what does the pudendal canal contain?
pudendal nerve
internal pudendal vein
internal pudendal artery
What does the external anal sphincter do?
voluntarily controlled, compresses to keep shincter/canal shut
what does the internal anal sphincter do?
involunatrily controlled, relaxed during defecation
what structure is lateral to the anal sphincters?
ischial rectal fossa
where does the abdominal aorta bifurcate?
L4 - bifurcates into L and R common iliac arteries
What does the external iliac artery supply?
blood to the lower limbs
What does the internal iliac artery supply?
blood to pelvis
Where do common iliac arteries bifurcate?
sacroiliac joint - split into intrnal and external iliac arteries
where does internal pudendal artery branch off from?
internal iliac artery
where does IMA come from?
abdominal aorta
what supplies blood to the rectum?
superior rectal artery (branch from IMA) and internal iliac artery’s middle and inferior rectal arteries (with internal iliac artery coming from L/R iliac artery)
