Download the superficial perineal pouch

the perineum
is a diamond shaped area below the pelvic diaphragm, is bounded by
:
1-the pubic symphysis anteriorly
2-tip of coccyx posteriorly
3-ischial tuberosities laterally on each side
it include ;urogenital & anal triangles
the urogenital triangle is bounded by the pubic arch & ischial
tuberosities. it includes 2 spaces (pouches) , a superficial perineal
pouch & urogenital diaphragm(deep perineal pouch)
- the superficial perineal pouch
is enclosed between the membranous layer of superficial
fascia(below) & the perineal membrane(above)
-contents in the male includes:
1-the root of the penis which include bulb of the penis & two crura of
the penis
2-bulbospongiosus(applied to bulb) & ischiocavernousus muscles
(applied to crura)
3-perineal branch of the pudendal nerve
4-superficial transverse perinei muscle
-contents in the female
1-the root of clitoris which includes bulb of the vestibule & 2 crura of
clitoris
2-bulbospongiosus & ischiocavernousus
3-superficial transversus perinei muscle
4-perineal branch of pudendal nerve
the perineal body: a small mass of fibrous tissue gives attachment
to 1- external anal sphincter 2-bulbospongiosus muscle 3- superficial
transversus perinei muscle
-the deep perineal pouch
is the space enclosed between the perineal membrane below & the
endopelvic fascia above , within the urogenital diaphragm
-contents in the male includes:
1-membranous part of urethra
2-the sphincter urethrae muscle
3-bulbourethral glands
4-deep transversus perinei muscle
5-internal pudendal vessels & their branches
6-dorsal nerve of the penis
-contents in the female include :
1-part of the urethra
2-part of the vagina
3-sphincter urethra surrounding 1 & 2
4-deep transverse perinei muscle
5-the internal pudendal vessels & their branches
6-the dorsal nerve of clitoris
* the perineal body in the female is larger than in the male & more
important , is wedge shaped between lower end of vagina & the anal
canal
- the penis
has a fixed root & a body that hangs free
the body of penis composed of 3 cylinders of erectile tissue enclosed
in a tubular sheath of fascia called buck's fascia . the erectile tissue
made up of 2 dorsally placed corpora cavernosa & a single corpus
spongiosum which is traversed by the urethra. the distal part of
spongiosum is called glans penis with slit like opening the external
urethral meatus
blood supply of the penis by:
1-dorsal artery of penis on the dorsum
2-deep arteries of penis to corpora cavernosa
3-artery of the bulb
all these branches are infact coming from the internal pudendal
artery
-venous drainage to internal pudendal vein
-the lymphatics of penis as:
1-skin of penis to superficial inguinal nodes
2-deep structure of penis to internal iliac nodes
-the scrotum is an outpouching from lower part of the anterior
abdominal wall it contains:
1-the testes
2-epididymus
3-lower end of spermatic cord
the wall of the scrotum consist of the following layers:
1-skin
2-dartos muscle (smooth m) as a superficial fascia , this replaces the
colle's fascia of the region
3-external spermatic fascia
4-cremaster fascia
5-internal spermatic fascia
6-tunica vaginalis of testes
the scrotum is supplied by 1-external pudendal branches of femoral
artery, 2- scrotal branches of internal pudendal arteries
lymphatics: 1-skin ------- to superficial inguinal group
2-testes------along spermatic cord to para aortic lymph
nodes group at the level of L1 vertebra
nerve supply: 1-ilio inguinal n
2-genital branch of genitofemoral n
3-branches from perineal nerve
4-posterior cutaneous n of thigh
the urethra in the male :
1-prostatic urethra ; 3-4 cm in length , is the widest & more
distenable part of the entire urethra traverse the urethra from base
to apex on its posterior surface is the urethral crest
on each side
of it the prostatic sinus (for opening of prostatic glands), on the
summit of the crest is the prostatic utricle ,on the edge of the
opening of this utricle is the opening of the ejaculatory duct
2-membranous urethra; about 1.25-1.5 cm , traverses the urogenital
diaphragm & is surrounded by the sphincter urethra .it is the least
dilatable part of the urethra
3-penile urethra; about 16 cm in length, it traverse the corpus
spongiosum & terminal into the external urethral meatus(which is
the narrowest part of the urethra)
the female urethra:
is about 4 cm in length , starts at the neck of bladder & ends as
external meatus into the vestibule of vagina. it traverses sphincter
urethrae, immediatly infront of the vagina.around the external
meatus opens the duct of paraurethral gland (it corresponds to the
prostate)
the greater vestibular gland(mucous secreting)
opens into the vestibule of vagina by opening between the hymen
and posterior part of labia minora
THE VULVA:
Vulva means the external genitalia in the female
includes:
1. Mons pubis
2. The clitoris
3. Labia majora
4. Labia minora
5. The vestibule of the vagina
6. The bulb of the vestibule
7. The greater vestibular glands
Nerve supply by :
 Ilio-inguinal
 Genital branch of the genitofemoral
 Branches of perineal nerves
 Posterior cutaneous nerve of the thigh
THE VAGINA
Muscular tube extends upward and backward between the vulva
and the uterus
Of about 8-10 cm in length The cervix of uterus pierces its anterior
wall, and there are 4 fornices around the entrance of the cervix.
The upper ½ of the vagina lies above the pelvic floor, While the
lower ½ below the pelvic floor. The vagina is supported by:
a- Perineal body to lower 1/3
b- Urogenital diaphragm middle 1/3
c- The upper 1/3 is supported by the transverse cervical
pubocervical and sacrocervical ligaments
BLOOD SUPPLY BY:
1- The vaginal artery from the anterior division of the internal iliac
artery
2- Vaginal branch from the uterine artery
VENOUS DRAINAGE: to the internal iliac veins
LYMPHATIC DRAINAGE: 1- upper1/3 1- internal and external iliac
2-middle 1/3  internal iliac nodes
3-Lower 1/3 superficial inguinal nodes
NERVE SUPPLY:
1- Upper part by branches from inferior hypo gastric plexus
2- Lower part around vaginal opening ilioinguinal and dorsal
nerve of clitoris
MONS PUBIS :
Hair bearing elevation of skin anterior to the pubis
CLOTORIS: at anterior aspect of the vestibule ,the glans of clitoris is
hidden by the prepuce (skin).
LABIA MAJORA:
a prominent hair bearing folds of skin extends from mons pubis to
unite posteriorly in the mid line.
LABIA MINORA: hairless folds of skin lying between the labia
majora ,anteriorly they split to enclose the clitoris forming anterior
prepuce and posterior frenulum . The posterior ends form
fourchette .
The vestibule: a triangular area bounded on each side by the labia
minora. The clitoris is a tits apex , While the fourchette at its base.
THE ANAL TRIANGLE
Is the posterior part of the perineum , Is bounded behind by tip of
coccyx and on each side by ischial tuberosity and the sacrotuberous
ligaments. In its middle part is the anus (opening of anal canal) and
on each sie of it is the ischiorectal fossa .
THE ANAL CANAL:
Is about 4 cm , passes downward and backward from rectal ampula
opposite tip of coccyx to the anus below , related posteriorly to
anococcygeal body, laterally to ischiorectal fossa , While anteriorly
into perineal body, membranous urethra and bulb of penis , While
female to urethra and lower part of vagina
MUCOSA OF
UPPER HALF
1-lines by
columnar
epithelium
2-show anal
columns and
valves
MUCOSA OF
LOWER HALF
1- lined by
stratified
squamous
epithelium
2-no anal
columns & valves
3-Innervated
from
autonomic via
hypogastric
plexus
4-Supplied by
superior rectal
artery ( from
inferior
mesenteric)
5-Venous
drainage to
portal vein
6-Lymphatics
to pararectal
nodes and then
to inferior
mesenteric
nodes
7Embryologically
derived from
the hind gut
endoderm
3- Innervated by
inferior
rectal(somatic).
4-supplied by
inferior rectal of
internal
pudendal
(internal iliac)
5-to systemic
vein
6-drain to
superficial
inguinal nodes
7-derived from
ectoderm and
the proctoderm
The pectineal line marks the junction between the upper and lower
halves of the anal canal .
Anal sphincters are :
 Internal anal sphincter (involuntary)
 External anal sphincter (voluntary)
The internal sphincter is surrounding the upper part of the anal
canal and is smooth in nature.
The external includes 3 parts as:
1- Subcutaneous encloses lower end of the canal
2- Superficial extends between coccyx and perineal body
3- Deep part encircles the upper part of the canal and surrounding
the internal sphincter
Both 1 and 3 has no bony attachment.
The puborectalis part of levatorani blends with the deep part of the
external sphincter forming a slip as passing around junction of
……….?
Rectum- anal canal & is attached to the pubic bones in front
At junction of rectum- anal canal the internal sphincter
,puborectalis and deep part of the external sphincter form anorectal ring
ISCHIO-RECTAL FOSSA:
A wedge-shaped space on each side of the anal canal
1- Base by skin
2- Medial wall  by the sloping evator ani
3- lateral wall  lower part of obturator interna
It contains:
1- Dense fatty tissue to support the anal canal during defecation
2- The pudendal canal near the lateral wall of the canal
3- The inferior rectal nerve and artery cross the fossa from lateral
to medial to reach the anal canal
THE PUDENDAL NERVE:
A branch from sacral plexus , passes through both greater and
lesser sciatic foramina ,then run in the pudendal canal ,here it give
rectal branch (to supply external sphincter ) and skin of perineum ,
then divides into:
 Dorsal nerve of penis or clitoris
 Perineal branch to supply muscles of the 2 perineal paces then
continue as posterior scrotal or (labial)) to skin of scrotum or of
labia majora.
INTERNAL PUDENDAL ARTERY: A branch of internal iliac, has
the same course as pudendal nerve it gives:
1- Inferior rectal artery
2- Artery of the bulb of penis or of bulb of vestibule in female
3- Deep artery of penis into the corpus cavernosum
4- Dorsal artery of the penis.