Pelvic Cavity and Perineum Flashcards
boarders of pelvic inlet
sacral promentory ala of sacrum arcuate line pectin pubis pubic crest
boarders of pelvic outlet
pubic arch
ischial tuberosities
sacrotuberous ligament
coccyx
describe features of female pelvis
broader shorter wide pubic angle wide sacrum built for partuition
describe feature of male pelvis
narrow tall narrow pubic angle narrow sacrum built for strength and movement
8 ligaments for pelvic stability
sacrospinous sacrotuberous ventral sacroiliac dorsal sacroiliac iliolumbar superior pubic arcuate pubic anteiror longitudinal
what induces loosening of pelvic ligaments for childbirth
relaxin
muscles of the levator ani
puborectalis
pubococcygeus
iliococcygeus
pelvic floor muscles
puborectalis
pubococcygeus
iliococcygeus
coccygeus
what is the purpose of the puborectalis muscle
supports the rectum
relaxation facilitates defecation by reducing the angle of the rectum
muscles of pelvic wall
lateral- obturator internus
posterior- piriformis
branches of the posterior division of internal iliac artery
iliolumbar
lateral sacral
superior gluteal
branches of the anterior division of internal iliac artery
umbilical (superior vesicle) obturator inferior vesicle/vaginal (artery to ductus deferens) uterine middle rectal internal pudenal inferior gluteal
path of iliolumbar
exits pelvic area
branches into:
lumbar- goes up side of lumbar spine
deep circumflex iliac artery- goes around iliac spine
branches of umbilical
superior vesical
superior part is obliterated and forms the medial umbilical ligament
what is the female equivalent of the inferior vesicle artery
vaginal artery
where does the superior rectal artery come from and what does it supply
from the inferior mesenteric
supplies rectum and anal canal to pectinate line
where does the ovarian/testicular artery come from and what does it supply
branch off abdominal aorta
supplies the ovary, uterine tube, and upper uterus (or testis)
what organs are in the pelvic cavity
bladder
rectum
reproductive organs
what is the trigone
smooth triangular area around where the ureters come in on the bladder wall
what is the embryological origin of the muscular wall of the bladder
splanchnic mesoderm
what is the embryological origin of the trigone
intermediate mesoderm
what is the detrusor muscle and how does it work
muscle of bladder wall
passively expands during filling and actively contracts via parasympathetic innervation during voiding
relationship between internal bladder sphincter and detrusor muscle
contraction of the detrusor muscle triggers relaxation of the internal sphincter
what triggers detrusor muscle contraction
stretch reflex as bladder fills
blood supply of urinary bladder
superior and inferior vesical arteries
lymphatic drainage of bladder
internal iliac nodes
innervation of bladder
detrusor- parasympathetic
trigone + neck- sympathetic
what are the boarders of the ishiorectal fossa
medial/superior- levator ani
lateral- obturator internus with pudenal canal
inferior- skin and superficial fascia
filled with fat
blood supply of rectum
superior rectal (IMA branch)- rectal mucosa and superior rectal wall middle rectal (internal iliac branch)- middle muscular rectal wall inferior rectal (branch of internal pudenal)- distal rectum
rectum innervation
lumbar and sacral splanchnics (sympathetic)
parasympathetic referred pain
where is the pectinate line
divides the anal canal
above- endoderm: anal sinuses, anal columns, valves
lower- ectoderm: transition between smooth and hairy skin
what is significance of anal columns
superior rectal veins terminate here
site of internal hemorrhoids
blood supply of anal canal
above pectinate line- superior rectal artery
below pectinate line- middle + inferior rectal artery
lymphatic drainage of anal canal
above pectinate line- internal iliac, superior rectal, inferior mesenteric
below pectinate line- superficial inguinal nodes
innervation of anal canal
above pectinate line- parasympathetic, pelvic splanchnic, no pain
below pectinate line- pudenal nerve, pain
boundaries of perineum
anterior- pubic symphysis
lateral- ischial tuberosities
posterior- coccyx
boundaries of superficial perineal pouch
between perineal membrane and colles fascia
contents of superficial perineal pouch
ishiocavernosus- superiolateral, covers greater vestibular glands (female)
bulbospongiosus= medial boarder, covers bulbs of clitoris/penis
superficial transverse perineus- between ischial tuberosities
greater vestibular gland (female)
what supplies the superficial perineal pouch
deep branches of perineal nerves and vessels
where is the deep perineal pouch
superior to perineal membrane but under the muscles of the superficial perineal pouch
male contents of deep perineal pouch
deep transverse perineal muscle
external urethral sphincter
bulbourethral gland (male)- in deep transverse perineal
compressor urethrae
female contents of deep perineal pouch
external urethral sphincter
compressor urethrae
urethrovaginal sphincter
smooth muscles
innervation of deep perineal pouch
dorsal artery, vein, and nerve of penis/clitoris
describe the male urethral sphincter
covers the anterior prostatic urethra
encircles the urethra at the base of the prostate
exits genital hiatus and spreads out
describe the female urethral sphincter
circular around bladder neck
spreads out around vagina, forming compressor urethrae and urogenital bulbs
what causes fecal incontinence
damage to the pelvic diaphragm
tearing of anal sphincter
nerve damage
what muscle maintains fecal continence
puborectalis
anal sphincters
