Pelvic urinary tract and rectum anatomy Flashcards
where does bladder lie?
behind pubic symphysis
apex of bladder? what arises here?
lies directly superior to pubic symphysis, most anterior portion of bladder
- median umbilical ligament (urachus) arises here
where does ureter enter bladder?
superior-lateral edges
where is bladder related to in males posteriorly?
- rectum, ductus deferens, seminal vesicles
where is bladder related to in females posteriorly?
cervix and upper vagina
trigone
prevents retrograde urine glow and helps compress ureter within bladder wall
- area between the orifices of the ureters superiorly and internal urethral orifice inferiorly
- sympathetically innervated
arterial supply of bladder?
- superior vesical aa. from umbilical a. (major supplier)
- middle vesical aa.
- inferior vesical aa.
venous drainage of bladder?
- drains into dense venous plexus around base/neck
- prostatic venous plexus in males
- vesico-vaginal plexus in females
- these drain to deep dorsal v. of penis and internal iliac v.
- ** important with prostatic cancer***
vascular supply of pelvic ureter?
common iliac a.
internal iliac a.
vasiculodeferential a. (male)
uterine/inferior viscal aa. (female)
where does pelvic ureter cross?
crosses iliac vessels anteriorly
- however, in females, the uterine a. also crosses the ureter anteriorly
uretal orifices
- where ureter opens into bladder at superior-lateral angles
- there are no valves
- pressure on bladder wall closes intramural ureters during distension and empyting of the bladder
what are the four parts of the male urethra?
- intramural portion: from bladder to upper portion of prostate
- prostatic: portion passing through prostate
- membranous: portion passing through UG diaphragm
- penile: portion from inferior surface of UG diaphragm
where are two luminal dilations of male penile urethra?
- bulb of penis
- glans of penis
external urethral orifice
“meatus”
- opening thu glans penis
what are 2 glans that open into penil urethra?
- bulbourethral (Cowper’s gland): opens into bulbar portion
2. urethral glands: small glands located throughout spongy body
what are two portions of female urethra?
- superior: similar to male prostatic urethra
2. membranous: pierces UG diaphragm
what vertebral level does rectum originate at?
3rd sacral vertebra at the rectosigmoid junction
- can be distinguished from sigmoid colon because it lacks mesocolon, teniae coli are spread out and surround the entire rectum.
two curvatures of the rectum?
- rectum proper: from origination to perineal flexure
2. anal canal: from perineal flexure to anus
anatomical vs. clinical anal canal
anatomical: from level of upper surface of pelvic diaphragm to anus
clinical: from pectinate line to anal verge
what portion of rectum contains peritoneum
ventral rectum
layers of rectum?
- muscular layer:
- outer longitudinal mm. - blend with fibers of levator ani at anal region
- inner circular mm: thickened to form internal anal sphincter - submucosal layer
- mucosal layer
Plica transversales
transverse rectal folds
3 folds: two left, one right
rectal columns:
mucous membrane overlying submucosal aa. and vv.
anal valves
archlike folds of mucous membrane connecting caudal ends of rectal columns
pectinate line
line formed by anal valves and rectal columns
dividing line for :
- venous drainage:
- superior drains to middle and superior rectal vv.
- inferior drains to inferior rectal vv. - lymphatic drainage:
- superior to pelvic nodes
- inferior to inguinal nodes - nerve supply:
- superior to autonomic nn.
- inferior to somatic nn. - eptithelial lining
pecten
stritified squamous non-keritonized
- area immediately below pectinate line
anal verge
stratified sqamous keritonzsed
- caudal-most portion of anal canal
superior rectal a.
- branch from IMA
middle rectal a.
- usually branches from internal iliac anterior division
inferior rectal aa.
from internal pudendal a.
what comes off posterior trunk of internal iliac?
- ilolumbar: supplies psoas/quadratus/iliacus m.
- lateral sacral aa.
- superior gluteal a.
what comes off anterior trunk of internal iliac a. ?
umbilical a. middle rectal inferior rectal obturator internal pudendal a. inferior gluteal a. uterine and vaginal a. vesiculodeferential a.
what are two pelvic vessels that don’t arise from internal iliac a?
- middle sacral a: arises from aorta along anterior surface of sacrum
- superior rectal a: branch from IMA
what makes up the lumbosacral plexus?
- lumbar plexus: ventral rami L1-4
2. sacral plexus: ventral rami L4-S3
what are five major nerves forming from lumbosacral plexus?
Anterior divisions: (supply flexors)
- obturator n.
- tibial n.(medial and lateral plantar n)
Posterior divisions:(supply extensors)
- common fibular n.
- femoral n.
general path of lymphatic drainage?
internal iliac nodes → external iliac nodes → common iliac nodes → lumbar nodes → cisternachyli → thoracic duct
lymphatics of urinary bladder?
drain to external iliac nodes laterally
internal iliac nodes
sacral and common iliac nodes
where do lymphatics of rectum drain?
below pectinate line - drain to superficial inguinal
above pectinate line - parallel course of major arteries:
- from rectal ampulla and sup. anal canal
along inf. rectal artery to internal iliac nodes - from most of rectum via pararectal nodes along middle rectal artery to internal iliac nodes
- from area of rectosigmoid junction along sup. rectal artery to inf. mesenteric nodes
male genitalia lymphatic drainage?
external iliac nodes
both int. & ext. iliac nodes
sacral & common iliac nodes
prostate lyphatics?
sacral nodes posteriorly and internal iliac nodes laterally
female genitalia lymph drainage?
- drain along ovarian vessle to lumbar nodes
where does parietal vs. visceral lymphatic drainage occur?
parietal – drain body wall lumbar nodes visceral – drain GI organs inf. mesenteric nodes sup. mesenteric nodes celiac nodes
