Perineum 2 Flashcards
Where do the superficial dorsal veins drain
external pudendal veins
Where do the deep dorsal veins drain
prostatic venous plexus
What arteries are involved in erections
deep arteries and branches of the dorsal artery
What type of arteries carry blood to the cavernous spaces in erectile tissue
helical arteries
What causes helical arteries to relax and fill
parasympathetics
How are helical arteries innervated
sympathetic and parasympathetic
What is the result of parasympathetics on helical arteries
inhibit sympathetics to allow corpus cavernosum to fill with blood
What is a penile fracture
hematoma within the corpus cavernosum under the tunica albuginea
What are the branches of the pudendal nerve
inferior rectal nerve perineal nerve (superficial and deep) dorsal nerve of penis (clitoris)
Where is inferior rectal nerve found
ischioanal fossa
What does inferior rectal nerve innervate
external anal sphincter
levator ani
sensory skin of the anal triangle
Where is the perineal nerve seen
UG triangle
What does perineal nerve innervate
motor supply to skeletal muscles in superficial and deep perineal pouches
provides sensory over posterior scrotum
What nerve is sensory to the penis
dorsal nerve of the penis
Where does the dorsal nerve of the penis enter
deep pouch
What nerves will innervate the anterior scrotum
ilioinguinal and genital branch of genitofemoral nerve
What nerves will innervate the posterior scrotum
pudendal nerve (via posterior scrotal nerves from superficial perineal)
What spinal cord levels are seen in the pudendal nerve
S2-S3-S4 (keeps the penis off the floor)
What is impotence
inability to get an erection
What are possible causes of impotence
damage to pudendal nerve or pelvic splanchnics
spinal cord trauma
What part of the autonomic system is involved in erection
parasympathetics
What part of the autonomic system is involved in ejaculation
sympathetics
How does viagra help impotence
affects relaxation of smooth muscle in corpora cavernosa to allow it to fill with blood
What structures compose the vulva
vestibular bulb mons pubic vestibule clitoris greater vestibular gland labia major labia minor
What is the mons pubis
collection of subcutaneous fat in front of the pubic symphysis
What is the labia major
fat filled prominence
What does the labia major contain
termination of round ligament of uterus
What is the labia
folds of skin that are devoid of fat and hair
What two parts compose clitoris
prepuce and frenulum
What is the vestibule
space between labia minor
What are the functions of the vulva
direct urine
prevent foreign objects entrance into UG system
sensory and erectile tissue
What muscles are found in the female perineum
bulbospongiosum
ischiocavernosum
superficial transverse perineal
What may occur if the perineal body is damaged and doesn’t heal properly
levator ani contract and pull the gap wider between pelvic floor and lead to proplapse of uterus, ovary, rectum
What muscle will lay on top of the bulb of the vestibule in females
bulbospongiosus
What is the vestibular bulb homologous to
bulb of penis
What is the function of the vestibular bulb
vaginal sphincter
aids in erection of clitoris
What do the corpora cavernosa form in females
clitoris
What muscle helps maintain erection of the clitoris
ischiocavernosus muscle
How does the ischiocavernosus muscle aid in erection of clitoris
compresses veins
What does the clitoris consist of
crus, body, glans and erectile tissue
What is the function of bartholins glands
secrete mucus to provide vaginal lubrication
Where will lymph drain in bartholinitis
superficial inguinal nodes
What are the branches of the internal pudendal artery in the female perineum
deep arteries
artery of bulb
post labial artery
dorsal arteries of clitoris
What will the external pudendal (deep and superficial) artery supply
labia majora skin
What will the superficial dorsal vein drain
skin, prepuce, clitoris
Where does the superficial dorsal vein empty into
superficial external vein and external iliac vein
What will the external pudendal vein drain
anterior labia majora and scrotum
Where does the external pudendal vein empty
femoral vein to prostatic plexus in males and bladder plexus in females
Where is the deep dorsal vein found
between Buck’s fascia superficial to tunica albuginea
What does the deep dorsal vein drain
glans and corpora cavernosa
Where does the deep dorsal vein empty in
prostatic plexus in males and bladder venous in females
What are the nerves of the female perineum
Perineal
Dorsal n of clitoris
Inferior rectal
What is the function of the inferior rectal nerve
innervates external anal sphincter, some levator ani, and sensory to skin of anal triangle
What is the function of the perineal nerve
runs into UG triangle, motor to skeletal m in superficial and deep perineal pouches, sensory viaposterior labial
What is the function of dorsal nerve of clitoris
sensory to clitoris
Where does the anal canal begin and terminate
sigmoid colon (ampulla) anus
What is the anal canal surrounded by
internal and external anal sphincters
What differentiates somatic and visceral innervation of the anal canal
pectinate line
What are contained within anal columns
terminal branches of superior rectal artery and vein that anastomose with middle rectal A/V
What are anal crypts
ducts of glands
What may occur to the anal crypts
form cysts or become infected (abscess)
What muscles compose the anorectal sling
puborectalis
internal and external anal sphincters
Is the internal anal sphincter voluntary or involuntary
Involuntary
What is the sympathetic innervation to internal anal sphincter
hypogastric plexus
What is the parasympathetic innervation to the internal anal sphincter
pelvic splanchnic
What is the effect on sympathetics on internal anal sphincter
stimulation
What is the effect of parasympathetics on internal anal sphincter
inhibition
What part of the anus is lined why true skin
part below the white line of Hilton
What is the innervation to the external anal sphincter
voluntary–inferior rectal nerve
How many parts compose the external anal sphincter
3 parts
Where does the external anal sphincter extend
surrounds entire length of anal canal
What are the 3 parts of the external anal sphincter
superficial
deep
subcutaneous
What is the subcutaneous part of the anal canal
surrounds lower part of the anal canal, sits beneath skin at anal orifice
What is the superficial part of the anal canal
arises from coccyx
What is the deep part of the anal canal
fused with puborectalis
What is the arterial supply to the visceral part of the anal canal
superior and middle rectal arteries
What is the arterial supply to the parietal part of the anal canal
middle and inferior rectal arteries
What are the veins of the visceral part of the anal canal
superior rectal arteries to portal system
What are the veins of the parietal part of the anal canal
inferior rectal arteries to caval system
What is the lymphatics of the visceral part of the anal canal
internal iliac nodes
What is the lymphatics of the parietal part of the anal canal
superficial inguinal
What is the innervation of the visceral part of the anal canal
pelvic splanchnic
inferior hypogastric
What is the innervation of the parietal part of the anal canal
inferior rectal nerves
How does defecation occur
reflex arc/path
What is the defecation reflex arc
ampulla gets filled and stimulates stretch receptors
defecation can occur consciously
relax puborectal sling, increase intraabdominal pressure
stimulate stretch receptors in anorectal canal and relax internal anal sphincter
What are the possible causes of incontinence
disruption of reflex arc
infants have weak external sphincter
weakening of external sphincter with age
inferior rectal nerve damage
