Perineum Flashcards
perineum
area of surface of trunk between thighs and buttocks
shallow compartment lying deep to this area and inferior to the pelvic diaphragm
includes anus and external genitalia
2 triangles of the perineum
anal triangle (with anal canal)
urogenital triangle (with outlets of the urinary and genital systems)
perineal body
central point of perineum
attachment of perineal muscles
fibromuscular mass
ischioanal fossa
fat-filled wedge shaped space located lateral to the anal canal and inferior to the pelvic diaphragm
pudendal canal of alcock’s
(obturator fascia)
pudendal n.
internal pudendal a. and v.
perineal n.
urogenital triangle may be divided into two spaces
superficial perineal space (or pouch)
deep peroneal space (or pouch)
Location of superficial perineal space (or pouch)
Lies between the inferior fascia of the urogenital diaphragm (perineal membrane) and the membranous layer of the superficial perineal fascia
Contents of superficial perineal pouch
superficial transverse perineal muscle
ischiocavernosus muscles
bulbospongiosus muscle
^all superior to the perineal membrane
Location of deep perineal space (or pouch)
lies between the superior and inferior fascia of the urogenital diaphragm
Contents of deep perineal pouch
deep transverse perineal muscle
sphincter urethrae muscle
bulbourethral glands (in the male)
muscles and glands in deep such are covered by ____ membranes both sides. This sheet forms the ______.
muscles and glands in deep such are covered by PERINEAL membranes both sides. This sheet forms the UROGENITAL DIAPHRAGM.
^ critical to maintain urinary incontinence
cryptorchidism
undescended testes
can be abd, inguinal canal, or high scrotal (80%)
nerves responsible for cremasteric reflex
afferent: sensory femoral branch of genitofemoral n. and ilioinguinal n.
efferent: motor fibers of genitofemoral n.
layer in scrotum corresponding to peritoneum in abd wall
tunica vaginalis
scrotum contents
- superficial (dartos) fascia
- external spermatic fascia
- cremaster m. and fascia
- internal spermatic fascia
- parietal layer of tunica vaginalis
- testis, visceral layer of tunica vaginalis
- skin of scrotum
varicocele
varicose veins in the pampiniform plexus of the spermatic cord appear like a “bag of worms” in the scrotum
more common on the left side, probably as a result of a malignant tumor of the left kidney which blocks the exit of the left testicular vein
hydrocele
accululation of fluid in the cavity of the tunica vaginalis of the testis or along the spermatic cord
PATENT PROCESSUS VAGINALIS
corpus cavernosum
two crura come together in the shaft portion of the penis, dorsal surface
THICKER tunica albuginea
corpus spongiosum
located on the ventral surface enlarges distally to form the glans penis (mushroom cap)
urethra passes thru
THINNER tunica albuginea, want to keep penile urethra open so semen can go thru
Colle’s fascia
deep membranous layer of the superficial perineal fascia and forms the inferior boundary of the superficial perineal pouch
Is continuous with the dartos fascia of the scrotum, with the superficial fascia of the penis and with Scarpa’s fascia of the anterior abd wall
roots of the clitoris are firmly anchored to
perineal membrane
female erectile tissue
clitoris
bulb of vestibule
In the female perineum, what fascia covers the 3 superficial perineal muscles?
deep perineal fascia of Gallaudet
greater vestibular (Bartholin’s) glands
located posterior and to L and R of opening of vagina
secrete mucus to lubricate vagina
inflammation/obstruction –> cyst
location of bulbourethral gland (male) vs. location of greater vestibular gland (female)
bulbourethral gland (male) –> deep puch
greater vestibular gland (female) –> superficial pouch
arterial supply of male perineum is mainly from
internal pudendal a. traveling though pudendal canal –> greater sciatic foramen –> lesser sciatic foramen
penile cancer will spread through which nodes
deep inguinal lymph node
scrotal cancer will spread to which node
superficial inguinal lymph node
testicular cancer will spread to which nodes
lumbar (caval/aortic) lymph node
ovarian cancer will spread to which nodes
spreads along suspensory ligament to lumbar (caval/aortic) nodes
cervical cancer will spread to which nodes
internal iliac nodes
vulva cancer will spread to which nodes
superficial inguinal nodes
perineum is innervated by sacral spinal cord segments dermatomes, which roots
S3-S5
which nerve is the major nerve of the perineum
pudendal n.
pudendal and illioninguinal n. block
(transvaginal n. block)
palpate first
might use for cyst of greater vestibular (Bartholin’s) glands
reflex erection
nerves responsible?
parasympathetic nerves
psychogenic erection
nerves responsible?
sympathetic nerves rom the pelvic splanchnic nerves which dilates the arteries supplying the erectile tissue
ejaculation
nerves responsible?
sympathetic
parasympathetic
spinal nerves (pudendal n.)
Friction to the glans penis and other sexual stimuli result in excitation of sympathetic fibers, leading to contraction of the smooth muscle of the epididymal ducts, the vas deferens, the seminal vesicles and the prostate in turn
mnemonic for nerves responsible for erection/ejaculation
Point (erection by parasympathetic) and Shoot (ejaculation by sympathetic)
why are females more likely to have urinary incontinence at older ages?
1) Shorter urethra.
2) sphincter is more sensitive to hormone (menopause is factor)
pudendal canal is formed by
what passes thru?
obturator fascia
INTERNAL pudendal ARTERY/VEIN,
pudendal n
