Male internal genital organs Lec -2-
The prostate gland
It is unpaired accessory gland of male reproductive system. It has the shape of
inverted cone it is about 3cm long from the apex and 3.5cm across the base. It
secret watery fluid contains phosphatase and protein which discharged into
the prostatic urethra. The prostate is surrounded by a fibrous capsule from
which a fibrous septa extend into the fibromuscular stroma.
The apex of the prostate projects inferiorly and rest on the superior fascia of
urogenital diaphragm.
The convex inferolateral surfaces lie on the levator ani muscle.
The posterior surface is flat and can be palpated by rectal examination.
The prostate has 5 lobes:
2 lateral lobes connected anteriorly by muscular part called the isthmus.
The posterior lobe lies below the ejaculatory duct.
The middle lobe lies between the prostatic urethra and the ejaculatory duct, it
is in direct contact with the trigon of the urinary bladder and bulge it upward
to from the uvula of the bladder.
The seminal vesicle
It is a sacculated tube about 15cm long coiled upon itself. It is bounded to the
base of urinary bladder lies below and lateral to the ductus deferens. The duct
of seminal vesicle united with the ductus deferens to form the ejaculatory
duct. It secrets an alkaline secretion contains fructose, mucus and coagulating
enzyme for the nutrition of the spermatozoa.
Ductus deferens
It is along muscular duct transport spermatozoa from the tail of the epididymis
in the scrotum to the ejaculatory duct. It ascends to the pelvis as a component
of the spermatic cord and passes through the inguinal canal to reach the pelvic
cavity. After passing through the deep inguinal ring ductus deferens bends
medially a crosses the external iliac artery and vein to enter the pelvic cavity, it
continuous inferomedially along the base of the bladder. The terminal portion
of the duct enlarged to form the ampulla of ductus deferens.
Blood supply of the prostate, seminal vesicle and ductus deferens
1- Superior vesical artery supply the superior part of the bladder, seminal
vesicle and ductus deferens.
2- Inferior vesical artery supply the base of the bladder, the prostate,
Seminal vesicle and ductus deferens through a slender branch called the
deferensial artery.
Veins are corresponding to the arteries drain to the internal iliac vein.
Lymphatic drainage to the sacral and internal iliac nodes.
The pelvic ureter
It is 12.5cm long in male begins by crossing the common or external iliac
vessels descends retroperitoneal in the lateral pelvic wall then anterior
to internal iliac artery where it crosses the umbilical, obturator artery
and nerve then pass medially crossed by ductus deferens to enter the
superolateral part of the urinary bladder. Ureter pass obliquely in the
wall of the bladder, the oblique termination with the narrow internal
opening and the contraction of the muscles of the bladder act as
sphincter to prevent reflux of urine.
In female it has different course it pass over the external iliac vein where
it forms the posterior and inferior relation to the ovarian fossa, then
pass along the uterus 1-2cm from the cervix at this point the ureter
crossed by the uterine artery.
Blood supply of the ureter
1- From the superior vesical artery.
2- From internal or common iliac artery.
3- In female it receives branches from the uterine artery.
Venous drainage
1- The inferior part drain into the internal iliac vein.
2- The superior part to the ovarian or testicular vein.
Lymphatic drainage pass to the lumbar nodes.
Male urethra
It is 20cm long pass through the prostate, urogenital diaphragm and the
penis so it divided into prostatic, membranous and spongy parts. In general the
urethra pass downward, forward, and downward in the penis.
Prostatic urethra
It is 3-4cm long pass along the prostate it is spindle shape. The posterior wall of
the urethra has urethral crest in the middle of this crest there is an elevated
area called the seminal colliculous in its center is a slit like opening directed
upward called the prostatic utricle on each side of the utricle the openings of
both ejaculatory ducts. On both sides of the urethral crest a deep groove called
prostatic sinus.
Membranous urethra
It is 1cm long pass through the perineal membrane surrounded by the
sphincter urethrae muscle. The bulbourethral gland lie on each side of the
urethra its duct open in the spongy urethra.
Spongy urethra
It is about 15cm long and 5mm in diameter begins from the bulb of the penis
pass through corpus spongiosa terminates in the external urethral opening
before it opens dilates in the glans penis to form the nevicular fossa. Several
urethral gland open into this part of the urethra.
Blood supply of the urethra
1- The prostatic part through prostatic artery from inferior vesical artery.
2- The membranous and spongy parts through the artery of the bulb of the
penis from the internal pudendal artery.
Venous drainage through internal iliac vein.
Lymphatic drainage
To the internal iliac nodes from the distal part of the spongy urethra pass to
the deep inguinal nodes.
Female urethra It is shorter than the male urethra, it is 4cm long and 5mm
in diameter it is held in position by pubourethral ligament. A number of
mucus gland open near the external urethral opening.
Blood supply of female urethra
1- Branches from vaginal artery.
2- Branches from internal pudendal artery.
Venous drainage to the internal iliac vein.
Lymphatic drainage to the internal iliac nodes.
Female internal genital organs
Include the ovaries, uterine tubes, uterus and the vagina.
The ovaries
It is an oval structure about 3cm long, 1.5cm wide they lie near the lateral
pelvic wall in the ovarian fossa which is bounded by
The ureter posteromedially
The external iliac vein laterally
The obturator nerve posterolateraly
The uterine tube anteriorly
The ovary attached to the superior border of the broad ligament of the uterus
by a short peritoneal fold called mesovarian. The medial end of the ovary
attached to the uterus by ovarian ligament. The lateral end of the ovary
attached to the lateral pelvic wall by the suspensory ligament of the ovary
through which the ovarian vessels pass to the hilum of the ovary.
Blood supply of the ovary
Through the ovarian artery which arise from the aorta below the renal artery
passes to the lateral pelvic wall enters the suspensory ligament of the ovary.
Venous drainage
Through a plexus of veins called pampiniform plexus then the ovarian vein
formed from the plexus , the right ovarian vein ends in the inferior vena cava
while the left one ends in the left renal vein.
Lymphatic drainage
Pass to the lumbar nodes.
The uterine tubes
Bilateral tubes extend from the lateral border of the uterus to the ovary, each
tube is about 10cm long divided into:
1- The intramural part or the uterine part pass through the wall of the
uterus.
2- The narrow isthmus lie in the free edge of the broad ligament at the
junction between the fundus and body of the uterus.
3- The dilated part the ampulla form most of the tubes passes in the lateral
pelvic wall curving over the ovary.
4- The funnel shape infundibulum it opens into the peritoneal cavity and
has a finger like projections called the fimbriae.
Posterior to the uterine tubes is the ovarian ligament and anterior to it is the
round ligament of the uterus.
Blood supply through ovarian and uterine arteries.
Venous drainage to the internal iliac vein.
Lymphatic drainage to the lumbar nodes.
The uterus
Thick walled muscular organ has a narrow lumen it is about 7.5cm long, 5cm
broad and 2.5cm in thickness. It is divided into
The fundus, the body which narrow inferiorly to form the isthmus and the
lower part the cervix.
The fundus is the upper rounded part lies above the junctions of the uterine
tubes.
The body it has a flat vesical (anterior) surface separated from the bladder by
uterovesical pouch, and a convex intestinal (posterior) surface which separated
from the rectum by rectouterine pouch (Douglas pouch).
The body of the uterus enclosed between the layers of the broad ligament
which connected the uterus to the lateral pelvic wall. The cavity of the uterus
is triangular in shape the apex of which is continuous with the cervical canal.
The body of the uterus is not straight there is an angle between it and the
cervix called anteflexion and between it and the vagina called anteversion.
The structure which support the uterus are:
1- The urinary bladder
2- The ampulla of the rectum.
3- The pelvic diaphragm.
4- The perineal body.
The cervix
The canal of the cervix is spindle shape open into the cavity of the uterus
through the internal os and to the vagina inferiorly through the external os.
The cervix divided into vaginal and supravaginal parts.
The supravaginal part lies above the vagina while the vaginal part lies within
the upper most part of the vagina surrounded by the vaginal fornices.
The cervix held in position by
1- Transverse ligament of the cervix which pass to the lateral pelvic wall.
2- Uterosacral ligament.
Blood supply of the uterus
1- Uterine artery branch from the internal iliac artery enters broad
ligament divided into ascending and descending branches.
2- Ovarian artery gives branches to the upper part of the uterus.
The venous drainage through uterine vein to the internal iliac vein.
Lymphatic drainage
1- The fundus drains to the lumbar nodes through the ovarian vessels.
2- Some lymphatic from the fundus pass through the round ligament to the
superficial inguinal nodes.
3- Lymphatics from the body drains to the internal or external iliac nodes.
4- The cervix drains to internal iliac and lateral sacral nodes.
The vagina
It is a muscular tube descends anteroinferiorly between the levator ani
muscles pierces the urogenital diaphragm to open into the vestibule.
The vagina enclose the cervix superiorly forming sacs between it and the
cervix called the fornices which are 4 in number anterior , posterior and 2
lateral, the anterior one is short while the posterior one is long.
The anterior wall of the vagina is in relation to the base of the bladder and
the terminal part of the ureter superiorly and to the urethra inferiorly.
The posterior wall related to the ampulla of the rectum through
rectouterine pouch.
Inferiorly the vagina is in relation to the perineal body.
The mucus membrane of the vagina contains a thick transverse mucosal
folds called vaginal rugi.
Blood supply of the vagina
1- The vaginal artery which is a branch from the internal iliac artery.
2- Twigs from middle rectal artery.
3- The descending branch of the uterine artery.
4- The lower part of the vagina receives branches from the internal
pudendal artery.
Venous drainage through vaginal and uterine veins to the internal iliac vein.
lymphatic drainage
1- The upper part drains to the internal iliac or sacral nodes.
2- The middle and lower part to the internal or external nodes.
3- The lowest part to the superficial inguinal nodes.
Vessels of the lesser pelvis
The internal iliac artery branch from the common iliac artery it supply the
viscera of the lesser pelvis, the perineum, the greater part of the gluteal
region and the iliac fossa. It gives anterior and posterior branches.
The anterior branches are
1- The umbilical artery gives 2-3 superior vesical arteries to the bladder
then it loses its lumen to form the medial umbilical fold.
2- The obturator artery supply the adductor compartment of the thigh.
3- The inferior vesical artery supply the base of the bladder, seminal
vesicle, prostate and sends deferential artery to supply ductus deferens.
The vaginal artery in female which corresponds to the inferior vesical
artery supply the vagina, the posteroinferior part of the bladder and the
pelvic urethra.
4- Uterine artery may arise from the vaginal, umbilical or the middle rectal
artery, supply the uterus and anastomosed with the ovarian artery,
5- The middle rectal artery supply the rectum, prostate, seminal vesicle or
vagina in female.
6- The internal pudendal artery supply the perineum.
7- The inferior gluteal artery,
The posterior branches are:
1- The superior gluteal artery.
2- The iliolumbar artery divided into iliac branch supply iliacus muscle and
lumbar branch supply psoas and quadratus lumborum muscles.
3- The lateral sacral artery supply the structures within the sacral canal.
Venous drainage of the pelvis through the internal iliac, superior rectal,
median sacral and ovarian veins.
Lymph nodes of the lesser pelvis
1- The external iliac nodes drain the lower limb, abdominal wall and pelvic
viscera drain into the common iliac nodes.
2- The internal iliac nodes receive the lymph from pelvic viscera, the
perineum, the gluteal region and the back of the thigh drain into the
common iliac nodes.
3- The sacral nodes drain the posterior pelvic wall and the pelvic viscera.
Nerves of the lesser pelvis
Sacral plexus
Formed by the ventral rami of S1-S4 nerves and the lumbosacral trunk (L4 and
L5) the plexus lies anterior to the piriformis muscle.
Branches from the ventral rami before it form the plexus are:
1- Branch to piriformis muscle.
2- Branches to coccygeus and levator ani muscle.
3- Pelvic splanchnic nerves from S2, S3 and S4 contain preganglionoc
parasympathetic nerve fibers to the inferior hypogastric plexus.
Branches arise from the anterior surface of the plexus
1- Nerve to quadratus femoris muscle.
2- Nerve to obturator internus muscle.
Branches from the dorsal surface of the plexus
1- The superior gluteal nerve.
2- The inferior gluteal nerve.
3- The perforating cutaneous nerve to the gluteal skin.
4- The perineal branch.
Terminal branches of the sacral plexus
1- Sciatic nerve.
2- Pudendal nerve.
The inferior hypogastric plexus of nerves
It is the direct continuation of the superior hypogastric plexus of the abdomen
divided into plexus surrounded the common iliac arteries. They receive the
pelvic splanchnic nerves.
The visceral plexus
1- The rectal plexus supply the rectum, sigmoid and descending colon.
2- Vesical plexus supply the urinary bladder.
3- The prostatic plexus supply the prostate, membranous urethra and the
penis.
4- The uterine and vaginal plexus.