Lecture 34: Pelvis, Perineum, and Female Reproductive Anatomy Flashcards
what keeps everything in the abdomen from falling out
the pelvic diaphragm
what are the openings in the male pelvic diaphragm (front and back)
front is urethral hiatus, back is anorectal hiatus
what are the openings in the female pelvic diaphragm
front is urethra, then vagina, then rectum
what muscles comprise the levator ani
iliococcygeus, pubococcygeus, puborectalis
what muscles comprise the pelvic diaphragm
levator ani and ischiococcygeus (NOTE THAT COCCYGEUS IS NOT PART OF THE LEVATOR ANI!!!)
where is the external anal sphincter in relation to the pelvic diaphragm
it is below it
what does the inferior rectal nerve branch from
pudendal nerve
types of muscle in external vs internal anal sphincter
external is skeletal, internal is smooth
shape of anal canal in saggital view
it is curved (only appears straight in a coronal view)
two triangles in pelvic diaphragm
urogenital and anal
where is fat located in the anal triangle
below levator ani before skin
what does fat in the anal triangle allow
expansion of vagina
what are the pelvic and urogenital diaphragm surrounded by
fascia
what is the name of the fascia that covers the urogenital diaphragm
inferior fascia (perineal membrane)
where are the bulbourethral glands in men
on the deep transverse perineal membrane of the urogenital diaphragm
why does the bladder have a flat top in women
because the uterus sits on top of it
why is it easier for women to get an infection than men
because the urethra is very short so bacteria can easily come up the tube
what kind of muscles in the bladder
smooth – cant work them out! but CAN train them to not feel as much pain when stretched
what type of muscles in the pelvic floor
skeletal (can work them out!)
parts of urethra in men
preprostatic (right off the bladder), prostatic, membranous, spongy
what structures can be found in the internal urethra
prostatic uricle, openings of ejaculatory ducts
nerves innervating the pelvic diaphragm
sympathetics from above (trunk, splanchnics) parasympathetics from S2-S4
what does sperm NOT go through
bladder, corpora cavernosa, seminal vesicles
what is corpum cavernosum for
making sure there is penetration
what is corpus spongiosum for
for passage of sperm
what kind of penis do most mammals have
an os penis
what function do female erectile tissues serve
stiffening of vaginal orifice
what is unique about erectile tissue in women
TWO distinct types
what kind of erectile tissue is the clitoris made from
corpus cavernosum (glands, crus, and body)
where is corpus spongiosum found in women
bulb of vestibule
the clitoris is NOT a mini penis because
it does not function in urine or sperm transport
what lubricates the vagina
greater vesticular glands
homologues in men and women corpus cavernosum
WOMEN: clitoris body and glans
MEN: dorsal paired penile bodies
homologues in men and women corpus spongiosum
women: bulbs of vestibule
MEN: bulb of penis, ventral body, glans
where are erectile tissues located relatively to UGD
superficial (in the in a space called the superficial/perineal pouch/space).
is the urethra enclosed in erectile tissue in women
NO!
what are erectile tissues covered by in both men and women
skeletal muscles
what are the skeletal muscles of superifical pouch in women
bulbospongiosus, ischiocavernosus, superficial transverse perineal
what are the skeletal muscles of superifical pouch in men
bulbospongiosus, ischiocavernosus, superficial transvere perineal
what does the superficial pouch contain
scrotal contents, erectile tissues, skeletal muscle coverings, and an outer layer of fascia
what is the homologue to the testes
ovaries
what is the homologue to the gubernaculum
round ligament
what is the homologue to the prostate
skene’s glands
what is the homologue to the prostatic uricle
uterus
what is the homologue to the bulbourethral glands
greater vestibular glands
where is fluid released from in women (female ejaculation)
from the urethra in a variably present prostate homolog (paraurehtral skene’s glands or female prostate) … may serve an antimicrobial purpose to prevent intercourse induced cystitis
bladder innervation
smooth muscle GVE fibers from lumbar splanchnics (sympathetic) & pelvic splanchnics (parasympathetic).
pelvic and UGD diaphragms and the superficial pouch
skeletal muscle GSE fibers from pudendal & other sacral spinal nerves (S2-4).
innervation of the ovary
GVA fibers travel back along the ovarian artery to T10.
innervation of the uterus and vagina
GVE fibers are from lumbar splanchnics (sympathetics), and pelvic splanchnics (parasympathetics). GVA fibers travel back along the same paths.
lymph flow of ovaries
Lymph flow from ovaries is to aortic lymph nodes (remember embryonic origin of ovary was higher, similar to testes).
where do the ovarian arteries come from
the abdominal aorta
why are the anastemoses in the uterine arteries important
women need a lot of blood flow here to support a pregnancy
what are the three branches off the internal iliac artery
uterine, vaginal, internal pudendal
where does uterus usually lie
in an inverted position over the bladder
how is vaginal expansion facilitated
by the fat in the fat in the anterior recess of the ischiorectal fossa.
what are the three layers of skeletal muscle in the pelvic region
pelvic diaphragm, deep pouch (UGD), and superficial pouch muscles covering erectile tissue
what holds the skeletal muscle in the pelvic region in place
cardinal/cervical ligaments
pouches in men vs women
men only have recto-vesicular
women have vesicouterine and rectouterine (2!)
what are the parts of the broad ligament in women
mesometrium
mesosalpinx
mesovarium
what occurs if something is incorrectly inserted into the vagina (think back alley abortion)
Instruments inserted through the vagina can pierce the posterior fornix and penetrate the peritoneal cavity.
where would dye introduced into the uterus emerge
ostia of uterine tubes and into the peritoneum
what causes the direct pain during ovulation
parietal peritoneum tears, causing direct pain.
what is the special kind of epithelium in the uterus allowing it to be stretched
transitional
in a pregnant woman, where would you get late pain from appendicitis
wherever the appendix ends up! organs end up moving alot because of uterus expansion
what are the main organs that get compressed during late term pregnancy
bladder and rectum
what can happen due to weakening of the muscles as a result of pregnancy
prolapse of organs
