Genito-Urinary Anatomy Flashcards
what is the role of the functional valve of bladder
prevents reflux into ureter
whats the diff btwn internal and external urethral sphincters
internal: smooth muscle from bladder
externa: skeletal muscle from pelvic floor
what are the 3 parts of male urethra
- prostatic urethra
- membranous urethra
- penile urethra
what is the inguinal canal
an oblique passage through the muscles of the anterior abdominal wall: extends from deep inguinal ring to superficial ring
what does the inguinal canal convey in males
spermatic cord (and ilio-inguinal nerve) also vas deferens, testicular artery, pampniform plexus of veins and neves/lymphatics of testis
what does the inguinal canal convey in females
round ligament
olio-inguinal nerve
genital branch of genitofemoral artery
what happens to structures as they pass through each of the abdominal wall layers
they gain a layer of tissue from each layer
what are the testes covered by
same 3 layers of spermatic fascia that cover the spermatic cord
what is the epidydmis
coiled tube laying along posterior border of each testis
what does the scrotum contain
testes
epididymis
lower part of spermatic cord
what is the glans penis
common outlet for urine and semen
what is the diff btwn direct/indirect hernia
direct: passes through transverse fascia of post wall, directly through internal oblique layer and directly through external ring
indirect: passes through each of 3 layers of abdominal wall in diff position
where do the gonads form in embryo
post abdominal wall and migrate from kidney level down to adult position
what is the kidney’s/gonads autonomic nerve supply from
t10-l2 nerve root
what is the tunica vaginalis
sac of peritoneum that partially surrounds testis
what factors normally prevent herniation of abdominal contents through inguinal canal
deep/superficial inguinal ring are in diff positions
- lower fibres of transversalis/internal oblique arch over canal and close it off during abdominal wall contraction
where would the ductus deferent be palpated?
it is attached to back of the testis and difficult to feel here. easy to feel in spermatic cord, feels like a hard cord
what is a varicocele
high pressure of venous blood in pampniform plexus of veins in the scrotum causes the veins to enlarge
what does the pampiniform plexus help regulate
temp
arteries supplying the testes run thro’ plexus where blood is cooled from abdominal arterial temp to testicular temp
where would lymph nodes be palpated to assess spread of testicular cancer
cancer of testis will spread to lymph nodes around aorta where testicular arteries arise
where is lymph drainage usually
lymph drainage of any organ follows arteries (but flow in opposite direction)
should undescended testis be corrected
yes bc spermatogenesis doesn’t occur at body temp: vital to ensure fertility
what anatomical structure in glans penis might impede progress of a catheter
navicular fossa
which nerves provide sensory innervation to scrotal skin
anterior 1/3 through ilii-inguinal nerve (L1)
posterior 2/3 is pudendal nerve (s2-4)
where does the aorta bifurcate
L4
what does the aorta bifurcate into at L4
common iliac arteries
where is the IVC formed by the unification of the common iliac veins
L5
what is the cremaster muscle
muscle of spermatic cord
what are renal calculi
small stones pass down ureter intobladder
what is left varicocoel
left testicular vein passes into left renal vein
disease of left kidney may block drainage of blood from lest testicle - scrotum veins become varicose
what is psoas spasm
appendix may lie on psoas, when it becomes inflamed the muscle goes into spasm: patient will have flexed hip. extending hip will be painful
renal tumours can become v large before they invade adjacent structures. what anatomical features explain this
they have thick and resilient capsule, surrounded by perinephric fat which is surrounded by perinephricfascia
what are 2 common variations in anatomy of renal pelvis and ureter
can be 2 ureters arising from kidney; sometimes they join and there is a single ureter entering bladder but sometimes they enter separately.
bladder doesn’t have valve mechanism; prone to urine passing back up to kidney when bladder contracts
what veins do r and l gonadal veins drain into
r - IVC
l - left renal vein
what is a polar artery?
when kidneys develop, they have a segmental pattern w a separate artery to each part.
- usually these arteries join to form single renal artery. 1 in 4 ppl have 2 renal arteries to 1 kidney; usually large renal artery and a smaller 1 to inferior pole of kidney; polar artery.
polar artery can compress ureter and stop urine flow
where would u palpate an abdominal aortic aneurysm
aorta finishes just above umbilicus so can only be felt in upper abdomen
what are the narrow parts of the ureter where a stone may get stuck
- where renal pelvis becomes ureter
- at pelvic brim
- where ureter passes through bladder wall
describe the relationship of the ureter to bony landmarks of abdomen/pelvis
- pelvis of L kidney is approximately L2-3 and R kidney is L3
- ureter commences at lower part of pelvis and runs down tips of transverse processes of lumbar vertebrae
- runs just medial to sacroiliac joint but usually directly over it inferiorly
- it runs across tip of spinous process of pelvis and medially into bladder
where does the femoral nerve pass from abdomen into thigh
under inguinal ligament
where does the obturator nerve pass from abdomen into the thigh
through obturator foramina
where does sciatic nerve pass from abdomen into thigh
through the greater sciatic foramen
what is the path of the ureter
- ureter enters pelvis
- crosses anteriorly to iliac vessels
- courses out to ischial spines
- courses medially to penetrate bladder base
what is the origin of the psoas
from the fascia on the sides of lumbar vertebra
what is the insertion of psoas
lesser trochanter of femur
which nerve supplies lateral thigh skin
lateral cutaneous nerve of the thigh (runs under inguinal ligament)
what is the recto-vesical pouch
lies btw rectum and urinary bladder (lowest part of peritoneal cavity)
what is the recto-uterine pouch aka
pouch of Douglas
what is most of the bladder’s mucosa like
rugose (wrinkled/conjugated)
what is the trigone
smooth triangular area of mucosa on inner aspect of bladder base (it’s sensitive to expansion)
what does the uterine artery arise from
anterior division of internal iliac artery
what is benign prostatic hypertrophy
enlargement of prostatic gland; may lead to blockage of urethra and inability to pass urine (requires emergency catheterisation)
where does venous drainage from the prostate pass
into a plexus of veins which lie anterior to the sacrum and communicate with veins which run up to azygous vein in chest
what are the 3 components of micturition control
- control from brain
- control from spinal cord
- sensory input from bladder
why is the ureter in danger of damaging during hysterectomy
ureter runs immediately under uterine artery
what steps urine passing from bladder back up to the ureter
ureter enters bladder at an oblique angle. as pressure in bladder rises, this presses on part of ureter which is in bladder and stops using passing back up to kidney
where does the bladder lie when full
against the lower abdominal wall, with no peritoneum between the bladder and the abdominal wall
a 25 yr old woman is in a car crash; suffered complete transection of SC at T6. is she able to tell when bladder is full?
no, signals cannot reach brain
what happens during micturition if there is loss of brain control
- bladder fills, SC knows bladder is full but this doesn’t reach brain
- SC asks brain to empty, brain doesn’t reply, SC completes normal emptying
- patient suddenly and unexpectantly passes urine with no control
(low pressure in bladder so no risk of renal failure)
what happens during micturition is there is loss of sensation
- SC and brain cannot know that bladder is full so don’t tell it to empty
- bladders fills and patient continually dribbles w high pressure in bladder/kidney can lead to kidney damage
(patient has no awareness of full bladder)
what happens during micturition if there is loss of spinal cord motor
- patient knows bladder is full but cannot empty
- high pressure in the bladder and renal failure
how is the body of the uterus usually placed
typically bent forwards and lies on superior surface of bladder
how does the cervix communicate with uterine cavity
via internal os (orifice)
how does cervix communicate with vagina
via external os (orifice)
how is the position of the cervix stabilised
levator ani muscle and cervical ligaments
how are ovaries attached to posterior of broad ligament
by a short mesentery (mesovarium)
what does the uterine artery anastomose with
ovarian artery
where does the vagina lie
- upper 2/3 in pelvic cavity
- bottom 1/3 in the perineum
what is the perineum
area btwn anus and scrotum/vulva (diamond-shaped)
what is the mons pubis
a rounded, hair bearing skin elevation located in front of pubic symphysis
where does the ductus deferent terminate
by joining duct of seminal vesicle to form the ejaculatory duct
do the seminal vesicles store sperm
no, they secrete thick alkaline fluid which forms the bulk of seminal fluid
where does the prostate gland lie
against neck of bladder
what is the prostate gland pierced by
urethra and ejaculatory ducts
what does the shaft of the penis consist of
3 erectile cylinders:
- corpus spongiousum
- paid corpora cavernosa
where on the thigh, may inflammation of the ovary result in pain? and why
medial aspect of thigh
- ovary lies in space btwn internal/external iliac arteries on lateral wall of pelvis
- immediately deep to peritoneum is obturator nerve; relays sensory info from medial thigh
- ovary mar irritate nerve and cause pain
what is a retroverted uterus
body of uterus is at an angle to the cervix with the body position more posteriorly
(if it is more anterior, it is ante-versed)
what maintains the normal position of the uterus
cardinal and broad ligaments
to which lymph nodes would cervical cancer spread?
internal iliac group
what structures may be palpable during examination through the vagina
- cervix
- spinous process ofpelvis
- contains of recto-uterine pouch
- ovaries
- bladder
- urethra
- rectum
- anal canal
what is the superficial perineal pouch
space btwn perineal membrane and fascia which encloses external genitalia
what is the perineal membrane
fibrous membrane lying btwn inferior pubic rami as far as back as ischial tuberosities; triangular with holes in midline for vagina, urethra and anteriorly for venous drainage from external genitalia
what is the urogenital diaphragm
most superior layer of deep perineal pouch
what is anterior to the vagina
bladder and urethra
what is posterior to the vagina
rectum and anus
what is lateral to the vagina
ureters and uterine arteries
what are the 2 main holes in the pelvic floor
- urogenital hiatus: anteriorly situated, allows passage of urethra (and vagina in females)
- rectal hiatus: centrally positioned, allows passage of anal canal
what kind of muscle are the ureters
smooth muscle
what is the abdominal supply of ureters
renal artery
testicular/ovarian artery
what is the pelvic supply of ureters
superior and inferior vesicle arteries
what is the bladder derived from
hindgut
how are the detrusor muscles fibres orientated
in 3 directions to retain structural integrity when stretched
what are the roots of the hypogastric nerve
t12-l2
what are the roots of the pelvic nerve
s2-4
what are the roots of the pudendal nerve
s2-4
what are the 3 parts of the penis
root, body, glans
what are the erectile tissues and what do they do
left/right crura and bulb of penis
these fill with blood during sexual arousal
what do the left and right crura form
the 2 corpora cavernosa
what are the leading cells responsible for
testosterone production
what are seminiferous tubules lined by
Sertoli cells
why is the scrotums skin wrinkled
helps to regulate temperature; decreases SA, heat loss is reduced
what does the scrotum receive arterial supply from
anterior and posterior scrotal arteries
what is the spermatic cord
a collection of vessels, nerves and ducts that run to and from the testes. surrounded by a fascia
what is the pampiniform plexus
a network of veins, responsible for the venous drainage of testes.
has a unique configuration; wraps itself around testicular artery
what is the prostate innervated by
inferior hypogastric plexus
what is the lumbar plexus formed from
anterior rami of l1/2/3/4
what is the Point and Shoot mnemonic for?
erection = Parasympathetic innervation ejaculation = Sympathetic innervation
what are the nerve roots of the pudendal nerve
s2-4
what is the sensory innervation of pudendal nerve
external genitalia of both sexes
and skin around anus, anal canal and perineum
what is the motor innervation of pudendal nerve
various pelvic muscles
external urethral sphincter
external anal sphincter
where is the sacral plexus located
posterior pelvic wall
where does the pudendal nerve leave the pelvis
greater sciatic foramen
what is the main arterial supply of pelvic cavity
internal iliac artery
where does the common iliac artery bifurcate
l5-s1
where does the internal iliac artery divide into anterior and posterior trunks
at the superior border of the greater sciatic foramen
what does the anterior trunk of int iliac artery supply
pelvic organs
perineum
gluteal and adductor regions of lower limb
what does the posterior trunk of int iliac artery supply
lower posterior abdominal wall
posterior pelvic wall
gluteal region
what are the 3 main vessels involved in pelvic venous drainage
external iliac
internal iliac
common iliac
what is the external iliac vein a continuation of
femoral vein (when it crosses under inguinal ligament)
what are the external genitalia collectively known as
vulva
what are 3 functions of the vulva
- . to act as sensory tissue during sex
- to assist in micturition by directing urine flow
- to defend internal reproductive tract from infection
what is the blood supply to the external genitalia
paired pudendal arteries
what is the cervix
lower portion of the uterus
how does the cervix facilitate sperm passage into the uterine cavity
via dilation of the external and internal os
what are the 3 parts of the uterus
fundus
body
cervix
where does the broad ligament attach
sides of the uterus to the pelvis
- contributes to maintaining it in position
where does the round ligament attach
extends from uterine horns to labia major via inguinal canal
- maintains anteverted position of uterus
what are PS fibres of uterus derived from
pelvic splanchnic nerves (s2-4)
what is the main function of the uterine tubes
to assist in transfer/transport of ovum from ovary to uterus
what are the 4 parts of the fallopian tube (lateral to medial)
- fimbriae
- infundibulum
- ampulla
- isthmus
where do gonads develop within
mesonephric ridge
how are ovaries attached to the posterior surface of the broad ligament
by the mesovarium
what are the 2 coverings of the testicles
- tunica vaginalis
- tunica albuginea
what is the path of the sperm from seminiferous tubules to epididymis
seminiferous tubules –> rete testes –> efferent tubules –> epididymis
how many days does the epididymis store sperm
50 days
where does the tail of the epididymis connect to
vas deferens
what branches off the abdominal aorta at t12
inferior phrenic arteries
what branches off the abdominal aorta at L1
coeliac trunk, middle suprarenal arteries
what branches off the abdominal aorta at lower L1
superior mesenteric artery
what branches off the abdominal aorta at L1/2
renal arteries
what branches off the abdominal aorta at L2
gonadal arteries
what branches off the abdominal aorta at L3
inferior mesenteric artery
what is diff btwn labia majora and minora
majora - hair bearing fold
minora - non-hair bearing fold
what are the 3 layers of the uterus
endometrium
myometrium
perimetrium
what are the 3 zones of the prostate gland
central
peripheral
transitional
where is sperm produced
seminiferous tubules of testis
