anatomy of the lower urinary
TRANSCRIPT
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Anatomy of the Lower Urinary
Tract and Male Genitalia
Benjamin I. Chung, MD l Graham ommer, MD l !ame" D. Broo#", MD
Bony Pelvis
Anterior Abdominal Wall
Soft Tissues of the Pelvis
Pelvic Circulation
Pelvic Innervation
Pelvic Viscera
Perineum
Thi" cha$ter $ro%ide" a general anatomic framewor# to guide
the $el%ic "urgeon. The &ony, ligamentou", and mu"cular
framewor# of the $el%i" i" $re"ented 'r"t. (e)t, the $el%ic
%e""el" and ner%e" and the genital, urinary, and ga"trointe"tinal
%i"cera are di"cu""ed. *inally, the $erineum and e)ternal genitalia
are re%iewed.
BONY P!VIS
The "elvic bones are the sacrum #the termination of the
a$ial s%eleton& and the t'o innominate bones( The latter
are formed &y the fu"ion of the iliac, i"chial, and $u&ic o""i'cation
center" at the aceta&ulum +*ig. -/. The i"chium and $u&i" al"o
meet &elow, in the center of the inferior ramu", to form the o&turator
foramen. The weight of the u$$er &ody i" tran"mitted from
the a)ial "#eleton to the innominate &one" and lower e)tremitie"
through the "trong "acroiliac +I/ joint". A" a whole, the $el%i" i"
di%ided into a &owl0"ha$ed fal"e $el%i", formed &y the iliac fo""ae
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and largely in contact with intra$eritoneal content", and the circular
true $el%i" wherein the urogenital organ" lie. At the $el%ic
inlet, the true and fal"e $el%e" are "e$arated &y the arcuate line,
which e)tend" from the "acral $romontory to the $ectineal line
of the $u&i". The lum&ar lordo"i" that accom$anie" erect $o"ture
tilt" the a)i" of the $el%ic inlet "o that it $arallel" the ground1 the
$el%ic inlet face" anteriorly, and the inferior i"chio$u&ic rami lie
hori2ontal +*ig. -/. 3hen a$$roaching the $el%i" through a low
midline inci"ion, the "urgeon ga2e" directly into the true $el%i".
The anterior and "osterior iliac s"ines) the iliac crests)
the "ubic tubercles) and the ischial tuberosities are "al"able
landmar%s that orient the "elvic sur*eon +"ee *ig.
-/. Coo$er +$ectineal/ ligament o%erlie" the $ectineal line and
o4er" a "ure hold for "uture" in hernia re$air" and urethral "u"$en"ion
$rocedure" +*ig. -5/. The i"chial "$ine i" $al$a&le tran"%aginally
and attache" to the $el%ic dia$hragm and the "acro"$inou"
ligament. The "acro"$inou" ligament "e$arate" the greater and
le""er "ciatic foramina. Together with the "acrotu&erou" ligament,
it "ta&ili2e" the I joint &y $re%enting downward rotation of the
"acral $romontory. The I joint, "yno%ial in ty$e, gain" additional
"trength from anterior and $o"terior ligament". In $el%ic trauma,
fracture" %irtually ne%er in%ol%e thi" joint &ut occur adjacent to
it. The $u&e", the thinne"t of the $el%ic &one", are nearly alway"
fractured, and their fragment" may injure the adjacent &ladder,
urethra, and %agina. 6e"ection or congenital nonunion of the
$u&e" +e.g., &ladder e)"tro$hy/ doe" not a4ect am&ulation &ecau"e
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of the "trength of the I joint +3aterhou"e et al, 7851 Golim&u
et al, 779/.
ANT+IO+ AB,O-INA! WA!!
S%in and Subcutaneous .asciae
To minimi/e scarrin*) incisions of the anterior abdominal
'all and 0an% should follo' !an*er lines of cleava*e(
The"e line" $arallel dermal collagen '&er" and are oriented
along line" of "tre"". They corre"$ond to the "egmental thoracic
and lum&ar ner%e". The "#in i" &ac#ed &y Cam$er fa"cia, a loo"e
layer of fatty ti""ue that %arie" in thic#ne"" with the nutritional
"tatu" of the $atient. The "u$er'cial circum:e) iliac, e)ternal
$udendal, and "u$er'cial inferior e$iga"tric %e""el" &ranch from
the femoral %e""el" to run in thi" layer +*ig". -; and -</. The
"u$er'cial inferior e$iga"tric %e""el" are encountered during inguinal
inci"ion" and can cau"e trou&le"ome &leeding during $lacement
of $el%ic la$aro"co$ic $ort".
Scar"a fascia forms a distinct layer dee" to Cam"er
fascia) althou*h it may be di1cult to discern in older
"atients( u$eriorly and laterally, it &lend" with Cam$er fa"cia.
Inferiorly, it fu"e" with the dee$ fa"cia of the thigh cm &elow
the inguinal ligament along a line from the anterior "u$erior iliac
"$ine to the $u&ic tu&ercle. Medially, it i" continuou" with Colle"
fa"cia of the $erineum +"ee *ig. -;/. Colle" fa"cia attache" to the
$o"terior edge of the urogenital dia$hragm and the inferior i"chio$u&ic
rami. It i" continuou" with the darto" fa"cia of the $eni" and
"crotum. The"e fa"ciae can limit &oth the "$read of infection in
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necroti2ing fa"ciiti" of the "crotum +*ournier gangrene/ and the
e)tent of urinary e)tra%a"ation in an anterior urethral injury. *or
in"tance, &lood and urine can accumulate in the "crotum and
$eni" dee$ to the darto" fa"cia after an anterior urethral injury. In
the $erineum, their "$read i" limited &y the fu"ion" of Colle" fa"cia
5; SCTION I = Anatomy
to the i"chio$u&ic rami laterally and to the $o"terior edge of the
$erineal mem&rane1 the re"ulting hematoma i" therefore &utter:y
"ha$ed. Becau"e of the"e fa"ciae, &leeding, infection, or urinary
e)tra%a"ation will not e)tend down the leg or into the &uttoc# &ut
can freely tra%el u$ the anterior a&dominal wall dee$ to car$a
fa"cia to the cla%icle" and around the :an# to the &ac#.
Abdominal -usculature
The a&dominal mu"culature lie" immediately &elow car$a fa"cia.
The origin" of the e)ternal o&li>ue, internal o&li>ue, and tran"%er"u"
a&domini" mu"cle" and the orientation of their '&er" are
$re"ented in Cha$ter . These muscles terminate on the
anterior abdominal 'all as broad) tou*h a"oneurotic
sheets that fuse in the midline #linea alba& and form the
rectus sheath +"ee *ig. -</. The linea al&a i" a%a"cular and i" a
con%enient $oint of acce"" to the $eritoneal and $el%ic ca%itie".
In it" u$$er $ortion, the anterior rectu" "heath i" formed &y the
a$oneuro"i" of the e)ternal o&li>ue mu"cle and a $ortion of the
internal o&li>ue mu"cle +*ig. -?/. The $o"terior "heath i" deri%ed
from the remaining internal o&li>ue a$oneuro"i" and the tran"%er"u"
a&domini" a$oneuro"i". Two third" of the di"tance from the
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$u&i" to the um&ilicu", the arcuate line i" formed, a" all a$oneurotic
layer" a&ru$tly $a"" anterior to the rectu" a&domini", lea%ing
thi" mu"cle clothed only &y tran"%er"ali" fa"cia and $eritoneum
$o"teriorly.
The rectus abdominis arises from the "ubis medial to
the "ubic tubercle and inserts on the $y"hoid "rocess
*igure -. The &one" and ligament" of the $el%i". +*rom @inman * !r. Atla" of
uro"urgical anatomy. hiladel$hia 3B aunder"1 775.
$. 7?./
Ilium
Arcuate line
Greater "ciatic
foramen
Le""er "ciatic
foramen
acral $romontory
acrum
Iliac fo""a
Iliac cre"t
Anterior "u$erior
iliac "$ine
Anterior inferior
iliac "$ine
Aceta&ulum
I"chio$u&ic
ramu"
I"chium
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u&i"
Coccy)
acrotu&erou" I.
acro"$inou" I.
I"chial "$ine
u&ic cre"t
u&ic tu&ercle
I"chial
tu&ero"ity
ectineal line
&turator
foramen
u&ic "ym$hy"i"
*igure -. el%i" in "tanding $o"ition. The a)i" of the $el%ic
ca%ity i" hori2ontal &ecau"e of lum&ar lordo"i". +*rom acharin 6*.
el%ic :oor anatomy and the "urgery of $ul"ion enterocele. (ew
Eor# $ringer0Ferlag1 7<. $. <./
*igure -5. To$ogra$hy +A/ and $o"terior wall +B/ of the left inguinal canal, %iewed
from the $re$eritoneal "$ace. The location of three
ty$e" of inguinal hernia i" demon"trated. +*rom chlegel (, 3al"h C.
imultaneou" $re$eritoneal hernia re$air during radical $el%ic
"urgery. ! Urol 78158./
A
B
*igure -;. Left, Anterior %iew of the dee$ fa"ciae of the a&domen, $erineum, and
thigh. (ote the "u$er'cial inferior e$iga"tric artery
$a""ing "u$eriorly in Cam$er fa"cia. Right, Midline "agittal %iew of the $el%ic fa"ciae
and their attachment".
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5? SCTION I = Anatomy
In*uinal Canal
The in*uinal canal transmits the s"ermatic cord in the
male) the round li*ament in the female) and the ilioin*uinal
nerve in both se$es +*ig. -81 "ee al"o *ig. -</. It"
anterior wall and :oor are formed &y the e)ternal o&li>ue mu"cle,
which fold" o%er at it" inferior edge a" the inguinal ligament.
A&o%e the $u&ic tu&ercle, the '&er" of the e)ternal o&li>ue a$oneuro"i"
"$lit to form the lateral edge" +crura/ of the e)ternal
inguinal ring. Tran"%er"e +intercrural/ '&er" &ridge the crura to
and ad2acent costal cartila*es( The mu"cle i" cro""ed &y three
or four tendinou" inter"ection" that are 'rmly attached to the
anterior rectu" "heath1 thu" the mu"cle can &e di%ided tran"%er"ely
without "igni'cant retraction. It i" "u$$lied &y the la"t "i) thoracic
"egmental ner%e" that enter it laterally. aramedian inci"ion"
lateral to the rectu" di%ide the"e ner%e", cau"e atro$hy of the
rectu", and $redi"$o"e to %entral hernia. Anterior to the rectu" and
within it" "heath, the triangle0"ha$ed $yramidali" mu"cle ari"e"
from the $u&ic cre"t and in"ert" into the linea al&a +"ee *ig. -</.
It i" "u$$lied &y the "u&co"tal ner%e +T/.
*igure -<. Mu"cle", %e""el", and ner%e" of the anterior a&dominal wall.
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia 58
again"t the :oor, $re%enting herniation of intra0a&dominal content"
into the canal. @ernia" into the canal may occur medial
+direct/ or lateral +indirect/ to the inferior e$iga"tric %e""el" +"ee
*ig". -5 and -8/.
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Internal Surface of the Anterior
Abdominal Wall
A$$roached la$aro"co$ically, three elevations of the "eritoneum)
referred to as the median, medial, and lateral
umbilical folds, are %i"i&le on the anterior a&dominal wall &elow
the um&ilicu" +*ig. -/. The median fold o%erlie" the median
um&ilical ligament +urachu"/, a '&rou" remnant of the cloaca that
attache" the &ladder to the anterior a&dominal wall. The o&literated
um&ilical artery in the medial um&ilical fold "er%e" a" an
form the "u$erior edge of the e)ternal ring. By di%iding the intracrural
'&er", the e)ternal o&li>ue can &e "e$arated along it" '&er"
to gain acce"" to the cord. The $o"terior wall of the canal i" formed
&y the tran"%er"ali" fa"cia, which line" the inner "urface of the
a&dominal wall. The cord "tructure" $ierce thi" fa"cia lateral to the
inferior e$iga"tric %e""el" at the internal inguinal ring +"ee *ig.
-5/. The internal inguinal ring lie" midway &etween the anterior
"u$erior iliac "$ine and the $u&ic tu&ercle, a&o%e the inguinal
ligament, and ; cm lateral to the e)ternal ring. *i&er" of the internal
o&li>ue and tran"%er"u" a&domini" ari"e from the ilio$"oa"
fa"cia and inguinal ligament lateral to the internal ring and arch
o%er the canal to form it" roof. They fu"e a" the conjoint tendon,
$a"" $o"terior to the cord, and in"ert into the rectu" "heath and
$u&i". The conjoint tendon reinforce" the $o"terior wall of the
inguinal canal at the e)ternal ring. 3ith contraction of the internal
o&li>ue and tran"%er"u" mu"cle", the roof of the canal clo"e"
*igure -?. Cro"" "ection of the rectu" "heath. Top, A&o%e the arcuate line, the
a$oneuro"i" of the e)ternal o&li>ue mu"cle form" the
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anterior "heath, and the tran"%er"u" a$oneuro"i" form" the $o"terior "heath. The
internal o&li>ue mu"cle "$lit" to contri&ute to &oth the
anterior and the $o"terior "heath". Bottom, Below the arcuate line, all a$oneuro"e"
$a"" anterior to the rectu".
5 SCTION I = Anatomy
+$u&ourethrali", $u&orectali"/, in"ert" directly into +$u&o%aginali",
$u&oanali", le%ator $ro"tatae/, or in"ert" into a "tructure intimately
a""ociated with the $el%ic %i"cera +Law"on, 78;/. The $u&o%i"ceral
grou$ $ro%ide" "trong ')ation and "u$$ort for the $el%ic
%i"cera. The coccygeu" mu"cle e)tend" from the "acro"$inou" ligament
to the lateral &order of the "acrum and coccy) to com$lete
the $el%ic dia$hragm. Mu"cle" of the $el%ic dia$hragm contain
ty$e I +"low0twitch/ '&er", which $ro%ide tonic "u$$ort to $el%ic
"tructure", and ty$e II +fa"t0twitch/ '&er", for "udden increa"e" in
intra0a&dominal $re""ure +Go"ling et al, 7/.The $iriformi"
mu"cle ari"e" from the lateral a"$ect of the "acrum and $a""e"
through and 'll" the greater "ciatic foramen to form the $o"terolateral
wall of the $el%i".
It is im"ortant to reco*ni/e that the "elvic dia"hra*m
is not 0at or bo'l sha"ed) as it is fre5uently de"icted( At
the urogenital and anal hiatu", the mu"cle" lie in a near0%ertical
con'guration and are thic#ened inferiorly +"ee *ig. -9/ +Broo#"
et al, 771 Myer" et al, 77/. Behind the anu", they :atten to
form a nearly hori2ontal dia$hragm, referred to a" the levator plate.
In the female, the le%ator $late $ro%ide" critical "u$$ort to the
$el%ic %i"cera, a" di"cu""ed later.
Pelvic .asciae
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The "elvic fasciae are not merely colla*enous6 they are
also rich in elastic tissue and smooth muscle( Thi" "ugge"t"
that they are acti%e in the "u$$ort, and $o""i&ly the function, of
the $el%ic %i"cera. The $el%ic fa"ciae are continuou" with the
retro$eritoneal fa"ciae and ha%e &een categori2ed "omewhat
im$ortant landmar# for the "urgeon. It may &e traced to it" origin
from the internal iliac artery to locate the ureter, which lie" on it"
medial "ide. During tran"$eritoneal la$aro"co$ic $el%ic lym$h
node di""ection, the o&turator $ac#et i" acce""ed &y inci"ing the
$eritoneum lateral to the o&literated um&ilical artery. In addition,
during the $erformance of tran"$eritoneal la$aro"co$ic or ro&otic
radical $ro"tatectomy, the medial um&ilical fold" are u"ed a" landmar#"
to guide the di""ection of the &ladder to e)$o"e the "$ace
of 6et2iu". The lateral um&ilical fold contain" the inferior e$iga"tric
%e""el" a" they a"cend to "u$$ly the rectu" a&domini".
SO.T TISS7S O. T3 P!VIS
Pelvic -usculature
Mu"cle" and fa"cia line the true $el%i" and form it" :oor. The
o&turator internu" ari"e" from the inner "urface of the o&turator
foramen and the o&turator mem&rane and $a""e" through the
le""er "ciatic foramen to in"ert on the femur +"ee *ig. -/. The
fa"cia on the $el%ic "urface of thi" mu"cle i" thic#ened into a tough
line e)tending from the lower half of the $u&i" to the i"chial "$ine.
Thi" tendinou" arc of the le%ator ani "er%e" a" the origin of the
mu"cle" of the $el%ic dia$hragm $u&ococcygeu" and iliococcygeu"
+*ig. -7/. The"e mu"cle" are not truly "e$ara&le, and they
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form a dia$hragm that clo"e" the $el%ic outlet. Anteriorly, a
narrow U0"ha$ed hiatu" remain", through which the urethra and
rectum e)it in the male, and the urethra, %agina, and rectum e)it
in the female +*ig. -9/. The mu"cle &ordering thi" hiatu" ha"
&een referred to a" pubovisceral &ecau"e it $ro%ide" a "ling for
*igure -8. Dee$ "tructure" of the left
inguinal canal, %iewed from the front.
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia 57
thic#en" around the $el%ic urogenital organ" to form their %i"ceral
fa"cia. The"e are not true ligament" &ut rather a me"hwor# of connecti%e
ti""ue and "mooth mu"cle in%e"ting the %i"ceral neuro%a"cular
$edicle" +DeCaro et al, 77/. The inner "tratum lie" ju"t
&eneath the $eritoneum and i" a""ociated with the entire ga"trointe"tinal
tract. In the $el%i", it co%er" the rectum and dome of
the &ladder and form" the rectogenital "e$tum +Denon%illier"
fa"cia/. Thi" "e$tum i" the de%elo$mental remain" of the rectogenital
$ouch of $eritoneum that e)tended &etween the rectum
and internal genitalia to the $el%ic :oor.
The $el%ic fa"ciae ha%e &een gi%en a confu"ing array of a$$ellation"
&y anatomi"t" and "urgeon" intere"ted in female $el%ic
organ $rola$"e. To add to the confu"ion, the "trength of $el%ic
fa"ciae can di4er "igni'cantly &etween indi%idual" and race"
and the"e di4erence" may $redi"$o"e "ome indi%idual" to $el%ic
ar&itrarily into outer, intermediate, and inner "trata. The outer
"tratum, or endo$el%ic fa"cia, line" the inner "urface of the $el%ic
mu"cle" and i" continuou" with the tran"%er"ali" layer of the
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a&domen. It i" ')ed to the arcuate line of the $el%i", Coo$er ligament,
the "acro"$inou" ligament, the i"chial "$ine, and tendinou"
arc of the le%ator ani. The intermediate "tratum em&ed" the $el%ic
%i"cera in a fatty, com$re""i&le layer that accommodate" their
'lling and em$tying. It" ti""ue" are ea"ily "we$t a"ide to re%eal the
retro$u&ic, $ara%e"ical, rectogenital, and retrorectal $otential
"$ace". All $el%ic %e""el" and "ome $el%ic ner%e" tra%el in thi"
"tratum and are "u&ject to injury when the"e $otential "$ace" are
de%elo$ed at "urgery. The intermediate "tratum coale"ce" around
%e""el" and ner%e" "u$$lying the $el%ic organ" to form named
ligament" +e.g., cardinal, utero"acral, lateral, and $o"terior %e"ical/
that "u"$end and tether the"e organ" in the $el%i". Thi" fa"cia al"o
*igure -. Male $el%i" and anterior a&dominal wall %iewed from &ehind. The
"acrum and ilia ha%e &een remo%ed. +*rom Ander"on !H.
Grant" atla" of anatomy. 8th ed. Baltimore 3illiam" J 3il#in"1 78. *ig. 5-;./
;9 SCTION I = Anatomy
They are not true ligament"1 rather, they are conden"ation" of
intermediate "tratum around %i"ceral neuro%a"cular $edicle". The
$eritoneum o%er the"e ligament" form" di"crete fold" +recto%e"ical
in the male and rectouterine in the female/ that can &e a$$reciated
at cy"tectomy +*ig. -5/. Ta#en a" a whole, the $el%ic fa"ciae form
a E0"ha$ed "ca4olding for the $el%ic %i"cera +"ee *ig. -/.
.asciae of the Perineum
and the Perineal Body
The wea#e"t $oint in the $el%ic :oor, the urogenital hiatu", i"
&ridged &y the urogenital dia$hragm, a "tructure uni>ue to
human" +"ee *ig. -9/. The '&rou" $erineal mem&rane lie" at the
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center of, and de'ne", the urogenital dia$hragm +"ee *ig". -;,
-9, and -;/. It i" triangular and "$an" the inferior i"chio$u&ic
rami from the $u&i" to the i"chial tu&ero"itie". o"teriorly, it end"
a&ru$tly1 the "u$er'cial and dee$ tran"%er"e $erinei run along it"
free edge +*ig. -</. The e)ternal genitalia attach to it" inferior
"urface1 "u$eriorly, it "u$$ort" the urethral "$hincter +di"cu""ed
later/. The $erineal &ody re$re"ent" the $oint of fu"ion &etween
the free $o"terior edge of the urogenital dia$hragm and the $o"terior
a$e) of the urogenital hiatu". Thi" $yramid0"ha$ed "tructure
form" the hu& of $el%ic "u$$ort. Firtually e%ery $el%ic mu"cle
+"u$er'cial and dee$ tran"%er"e $erinei, &ul&oca%erno"u", le%ator
ani, rectourethrali", e)ternal anal "$hincter, "triated urethral
"$hincter/ and fa"cia +$erineal mem&rane, Denon%illier", Colle",
and endo$el%ic/ in"ert into the $erineal &ody. At it" core are a&undant
ela"tin and richly inner%ated "mooth mu"cle, which "ugge"t"
that it may ha%e a dynamic role in "u$$ort. Damage to the $erineal
&ody during $erineal $ro"tatectomy ri"#" $o"to$erati%e
urinary incontinence.
P!VIC CI+C7!ATION
Arterial Su""ly
Major arterie" of the $el%i" are "ummari2ed in Ta&le -. At the
&ifurcation of the aorta, the middle sacral artery ari"e" $o"teriorly
and tra%el" on the $el%ic "urface of the "acrum to "u$$ly
&ranche" to the "acral foramina and the rectum. The common iliac
arterie" ari"e at the le%el of the fourth lum&ar %erte&ra, run anterior
and lateral to their accom$anying %ein", and &ifurcate into
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the e)ternal and internal iliac arterie" at the I joint +*ig. -?/.
The e)ternal iliac artery follow" the medial &order of the ilio$"oa"
mu"cle along the arcuate line and lea%e" the $el%i" &eneath the
inguinal ligament a" the femoral artery +*ig. -8/. It" inferior
e$iga"tric artery i" gi%en o4 $ro)imal to the inguinal ligament and
a"cend" medial to the internal inguinal ring to "u$$ly the rectu"
mu"cle and o%erlying "#in. Becau"e the rectu" i" richly collaterali2ed
from a&o%e and laterally, the inferior e$iga"tric arterie" may
&e ligated with im$unity. A rectu" myocutaneou" :a$ &a"ed on
thi" artery ha" &een u"ed to correct major $el%ic and $erineal
ti""ue defect". (ear it" origin, the inferior e$iga"tric artery "end" a
dee$ circum:e) iliac &ranch laterally and a $u&ic &ranch medially.
Both %e""el" tra%el on the ilio$u&ic tract and may &e injured
during inguinal hernia re$air. It" crema"teric &ranch join" the
"$ermatic cord at the internal inguinal ring and form" a di"tal
ana"tomo"i" with the te"ticular artery +*ig. -/. In <K of
$eo$le, an acce""ory o&turator artery ari"e" from the inferior e$iga"tric
artery and run" medial to the femoral %ein to reach the
o&turator canal. Thi" %e""el mu"t &e a%oided during o&turator
lym$h node di""ection.
$rola$"e +acharin, 7</. The "elvic fasciae have three
im"ortant com"onents8 #9& Anteriorly) the "ubo"rostatic
li*aments attach to the lower 'fth of the $u&i", lateral to the
"ym$hy"i" and to the junction of the $ro"tate and e)ternal "$hincter.
They are called the $u&ourethral ligament" in the female and
in"ert on the $ro)imal third of the urethra +*ig. - on the H)$ert
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Con"ult we&"ite/. +/ Laterally, the arcu" tendineu" fa"cia $el%i"
e)tend" from the $u&o$ro"tatic +$u&ourethral/ ligament to the
i"chial "$ine +"ee *ig. -/. Thi" fa"cia form" at the junction of
the endo$el%ic and %i"ceral fa"ciae. It "hould not &e confu"ed with
the arcu" tendineu" le%ator ani, which lie" a&o%e it" anterior
$ortion +*ig. -/. In the male, the arcu" tendineu" fa"cia $el%i"
i" found at the &a"e of a "ulcu" &etween the $el%ic "ide wall and
the $ro"tate and &ladder. In the female, it corre"$ond" to the
lateral attachment of the anterior &ladder wall to the $el%ic "ide
wall. ara%aginal "u"$en"ion $rocedure" for "tre"" urinary incontinence
entail lateral rea$$ro)imation of the %aginal wall to thi"
tendinou" arc +6ichard"on et al, 7/. The lateral &ranche" of the
dor"al %enou" com$le) are directly &eneath the arcu" tendineu"
fa"cia $el%i"1 thu" the endo$el%ic fa"cia "hould &e o$ened lateral
to thi" landmar#. In the female, the fa"cia e)tending medially
from thi" arch carrie" a %ariety of name" +$u&o%e"ical, $eriurethral,
urethro$el%ic ligament/ and $ro%ide" im$ortant "u$$ort to the
urethra and anterior %aginal wall. Damage to thi" fa"cia and it"
attachment" ha" &een im$licated in urethrocele, cy"tocele, and
"tre"" urinary incontinence. +5/ o"terior to the i"chial "$ine, the
fa"cia fan" out to either "ide of the rectum and attache" to the
$el%ic "ide wall a" the lateral and $o"terior %e"ical ligament". In
the female, the"e are the "trong cardinal and utero"acral ligament".
*igure -7. Mu"cle" of the true $el%i" +three0>uarter %iew/.
*igure -9. Location and contour of the le%ator ani and $el%ic %i"cera. A) Anterior
%iew demon"trating the near0%ertical orientation of the
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lateral wall" of the le%ator ani and the hori2ontal wing" at it" $o"terior "u$erior
a"$ect. B) Lateral %iew in which the le%ator ani ha" &een
made tran"$arent. The $erineal mem&rane &ridge" the urogenital hiatu", and the
urethral "$hincter 'll" much of the hiatu". C) Fiew of the
le%ator ani from &elow "howing the urogenital hiatu" and the thic#ened inferior
&order of the le%ator ani. The $erineal &ody and related
"tructure" are not "hown. +*rom Broo#" !D, Chao 30M, err !. Male $el%ic anatomy
recon"tructed from the %i"i&le human data "et. ! Urol
771<7?-8./
A B
C
*igure -. Fagina and "u$$orti%e "tructure" after
remo%al of the &ladder and uteru". The arcu" tendineu"
fa"cia $el%i" and the cardinal and utero"acral ligament"
+$aracol$ium/ form a continuou" "tructure that "u$$ort" the
$el%ic %i"cera. +*rom DeLancey !L. tructural "u$$ort of
the urethra a" it relate" to "tre"" urinary continence the
hammoc# hy$othe"i". Am ! &"tet Gynecol 77;18987./
*igure -5. eritoneal "urface" of the female and male $el%e". In the female, the
ureter $a""e" medial to the o%arian %e""el", then dee$ to
the uterine artery within the "u&"tance of the cardinal ligament. The "acrogenital
and "acrouterine fold" re$re"ent the $o"terior $ortion" of
$el%ic fa"cial "u$$ort.
*igure -;. tructure of the male "triated urethral "$hincter. A) Anterior $rojection
"how" the cone "ha$e of the "$hincter and the
"mooth mu"cle of the "$hincter. B) Fiewed laterally, the anterior wall of the
"$hincter i" nearly twice the length of the $o"terior wall,
although &oth are of com$ara&le thic#ne"". +*rom Broo#" !D, Chao 30M, err !. Male
$el%ic anatomy recon"tructed from the %i"i&le human
data "et. ! Urol 771<78./
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A
B
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ;5
*igure -<. Mu"cle" of the male $erineum. The
tran"%er"u" $erinei and i"chioca%erno"i frame the
urogenital dia$hragm. +*rom 3illiam" L, 3arwic# 6.
Gray" anatomy. 5<th Briti"h ed. hiladel$hia 3B
aunder"1 785. $. <59./
u$er'cial
fa"cia, mem&ranou"
layer
Cor$u" "$ongio"um
$eni"
Bul&o"$ongio"u"
I"chioca%erno"u"
Tran"%er"u"
$erinei
"u$er'ciali"
erineal
&ody
Le%ator ani
&turator
internu"
iriformi"
Coccygeu"
acrotu&erou"
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ligament
Coccy)
acrotu&erou"
ligament
Table 4:9(
Arterie" of the el%i"
A6TH6E (AMH 6IGI( ULIH
Middle "acral Aorta acral ner%e" and "acrum
$ternal Iliac Branches
Inferior e$iga"tric H)ternal iliac 6ectu" a&domini" mu"cle and o%erlying "#in andfa"cia
Dee$ circum:e) iliac Inferior e$iga"tric Inguinal ligament and "urrounding
"tructure" laterally
u&ic Inferior e$iga"tric Inguinal ligament and "urrounding "tructure" medially
Crema"teric Inferior e$iga"tric Fa" deferen" and te"ti"
Internal Iliac Branches
u$erior gluteal o"terior trun# Gluteu" mu"cle" and o%erlying "#in
A"cending lum&ar o"terior trun# "oa" and >uadratu" lum&orum mu"cle" and
adjacent "tructure"
Lateral "acral o"terior trun# acral ner%e" and "acrum
u$erior %e"ical Anterior trun# Bladder, ureter, %a" deferen", and "eminal %e"icle
Middle rectal Anterior trun# 6ectum, ureter, and &ladder
Inferior %e"ical Anterior trun# Bladder, "eminal %e"icle, $ro"tate, ureter, and the
neuro%a"cular &undle
Uterine Anterior trun# Uteru", &ladder, and ureter
Internal $udendal Anterior trun# 6ectum, $erineum, and e)ternal genitalia
&turator Anterior trun# Adductor mu"cle" of the leg and o%erlying "#in
Inferior gluteal Anterior trun# Gluteu" mu"cle" and o%erlying "#in
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;; SCTION I = Anatomy
*igure -?. 6ight internal and e)ternal iliac arterie". The ureter and %a" deferen"
$a"" medial to the %e""el". +*rom Clemente CD. Gray"
anatomy. 59th American ed. hiladel$hia Lea J *e&iger1 7<. $. 8<9./
A&dominal aorta
Common iliac a.
Dee$ iliac
circum:e) a.
Middle "acral a.
6ight ureter
Int. iliac artery
Iliolum&ar a.
u$erior gluteal a.
Lateral "acral a.
Inferior gluteal a.
Internal $udendal a.
ciatic ner%e
Middle rectal a.
Inferior %e"ical a.
eminal %e"icle
6ectum
Inferior
e$iga"tric a.
H)t. iliac a.
&turator a.
Medial um&il. lig.
Ductu" deferen"
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u$erior
%e"ical a.
Left ureter
Bladder
ro"tate gland
*igure -8. 6ight o&turator fo""a, "howing the iliac %e""el" and o&turator ner%e.
+*rom #inner DG. el%ic lym$hadenectomy. In Glenn
!*, editor. Urological "urgery. nd ed. (ew Eor# @ar$er J 6ow1 78<. $. <7./
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ;<
ana"tomo"e" with the inferior and "u$erior rectal arterie" in the
rectal wall. +5/ The inferior %e"ical &ranche" "u$$ly the lower
ureter, the &ladder &a"e, the $ro"tate, and the "eminal %e"icle". In
the female, they "u$$ly the ureter, the &ladder &a"e, and the
%agina. +;/ The uterine artery $a""e" a&o%e and in front of the
ureter +water :ow" under the &ridgeN/ to a"cend the lateral wall
of the uteru" and meet the o%arian artery in the lateral $ortion of
the fallo$ian tu&e +"ee *ig". -5 and -7/. The ureter i" %ulnera&le
during di%i"ion of the uterine $edicle". +</ The internal
$udendal artery lea%e" the $el%ic ca%ity through the greater "ciatic
foramen, $a""e" around the "acro"$inou" ligament, and enter" the
le""er "ciatic foramen to gain acce"" to the $erineum. It" $erineal
cour"e i" di"cu""ed later. +?/ The o&turator artery, %aria&le in origin,
tra%el" through the o&turator fo""a medial and inferior to the
o&turator ner%e and $a""e" through it" canal to "u$$ly the adductor"
of the thigh +"ee *ig. -8/. +8/ The inferior gluteal artery
tra%el" through the greater "ciatic foramen to "u$$ly the &uttoc#
and thigh.
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The internal iliac #hy"o*astric& artery descends in
front of the SI 2oint and divides into an anterior and a
"osterior trun% +"ee *ig. -?/. The $o"terior trun# gi%e" ri"e to
three $arietal &ranche" +/ the "u$erior gluteal, which e)it" the
greater "ciatic foramen1 +/ the a"cending lum&ar, which "u$$lie"
the $o"terior a&dominal wall1 and +5/ the lateral "acral, which
$a""e" medially to join the middle "acral &ranche" at the "ciatic
foramina.
The anterior trun% *ives o; seven "arietal and visceral
branches8 #9& The su"erior vesical artery arises
from the "ro$imal "ortion of the obliterated umbilical
artery and *ives o; a vesiculodeferential branch to the
seminal vesicles and vas deferens( The artery of the %a" deferen"
tra%el" the length of the %a" to meet the crema"teric and
te"ticular arterie" di"tally +"ee *ig. -/. Becau"e of the"e ana"tomo"e",
the te"ticular artery may &e "acri'ced without com$romi"ing
the %ia&ility of the te"ti". +/ The middle rectal artery gi%e"
"mall &ranche" to the "eminal %e"icle" and $ro"tate and
*igure -. Collateral arterial circulation to the te"ti". +*rom @inman * !r. Atla" of
uro"urgical anatomy. hiladel$hia 3B aunder"1 775.
$. ;78./
*igure -7. *emale internal genitalia, from &ehind. The ureter $a""e" &eneath the
uterine artery. +*rom @inman * !r. Atla" of uro"urgical
anatomy. hiladel$hia 3B aunder"1 775. $. ;9./
;? SCTION I = Anatomy
*igure -9. el%ic %enou" $le)u". A) Trifurcation of the dor"al %ein of the $eni",
%iewed from the retro$u&ic "$ace. The relation"hi$ of the
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%enou" &ranche" to the $u&o$ro"tatic ligament" i" "hown. B) Lateral %iew of the
$el%ic %enou" $le)u" after remo%al of the lateral $el%ic
fa"cia. (ormally the"e "tructure" are diOcult to "ee &ecau"e they are em&edded in
$el%ic fa"cia. +*rom 6einer 3G, 3al"h C. An
anatomical a$$roach to the "urgical management of the dor"al %ein and antorini"
$le)u" during radical retro$u&ic "urgery. ! Urol
787199./
The internal iliac artery can &e ligated to control "e%ere $el%ic
hemorrhage. Ligation decrea"e" the $ul"e $re""ure, allowing
hemo"ta"i" to occur more readily. Internal iliac &lood :ow doe"
not "to$ &ut re%er"e" it" direction &ecau"e of critical ana"tomo"e"
+lum&ar "egmental" to iliolum&ar1 median "acral to lateral "acral1
and "u$erior rectal and middle rectal/. Bilateral ligation almo"t
in%aria&ly $roduce" %a"culogenic im$otence.
Venous Su""ly
The dorsal vein of the "enis "asses bet'een the inferior
"ubic arch and the striated urinary s"hincter to reach
the "elvis) 'here it trifurcates into a central su"er<cial
branch and t'o lateral "le$uses +6einer and 3al"h, 787/
+*ig. -9/. To minimi2e &lood lo"" at radical retro$u&ic $ro"tatectomy,
the dor"al %ein com$le) i" &e"t di%ided di"tally, &efore it"
rami'cation. art of thi" com$le) run" within the anterior and
lateral wall of the "triated "$hincter1 thu" care mu"t &e ta#en not
to injure the "$hincter when "ecuring hemo"ta"i". The "u$er'cial
&ranch $ierce" the %i"ceral endo$el%ic fa"cia &etween the $u&o$ro"tatic
ligament" and drain" the retro$u&ic fat, anterior &ladder,
and anterior $ro"tate +"ee *ig. -9/.
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The lateral "le$uses s'ee" do'n the sides of the "rostate)
receivin* draina*e from it and the rectum) and
communicate 'ith the vesical "le$uses on the lo'er "art
of the bladder( Three to <ve inferior vesical veins emer*e
from the vesical "le$us laterally and drain into the
internal iliac vein( In the female, the dor"al %ein of the clitori"
&ifurcate" to em$ty into the laterally $laced %aginal $le)u"e".
The"e connect with the %e"ical, uterine, o%arian, and rectal $le)u"e"
and drain into the internal iliac %ein".
The internal iliac %ein i" joined &y tri&utarie" corre"$onding to
the &ranche" of the internal iliac artery and a"cend" medial and
$o"terior to the artery. Thi" %ein i" relati%ely thin walled and at
ri"# for injury during di""ection of the artery or the near&y $el%ic
ureter. The e)ternal iliac %ein tra%el" medial and inferior to it"
artery and join" the internal iliac %ein &ehind the internal iliac
artery. In half the $atient", one or more accessory obturator
veins drain into the underside of the e$ternal iliac vein
and can be easily torn durin* lym"hadenectomy +"ee *ig.
-8/.
Pelvic !ym"hatics
The $el%ic lym$h node" can &e diOcult to a$$reciate on gro""
e)amination &ecau"e they are em&edded in the fatty and '&rou"
ti""ue of the intermediate "tratum. Three major lym$h node
grou$" are a""ociated with the $el%ic %e""el" +*ig. -/. A "u&"tantial
$ortion of $el%ic %i"ceral lym$hatic drainage $a""e" through
the internal iliac nodes and their tributaries8 the "resacral)
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obturator) and internal "udendal nodes( The e)ternal
iliac node" lie lateral, anterior, and medial to the %e""el" and drain
the anterior a&dominal wall, urachu", &ladder, and, in $art, internal
genitalia. The e)ternal genitalia and $erineum drain into the
"u$er'cial and dee$ inguinal node" +"ee later di"cu""ion/. The
inguinal node" communicate directly with the internal and e)ternal
iliac chain". The common iliac node" recei%e e4erent %e""el"
from the e)ternal and internal iliac node" and the $el%ic ureter
and drain into the lateral aortic node".
P!VIC INN+VATION
!umbosacral Ple$us
The lum&o"acral $le)u" and it" rami are well illu"trated in Cha$ter
1 only the $el%ic cour"e" of it" ner%e" are re%iewed here +"ee *ig".
-8 and - and Ta&le -/. The iliohy"o*astric nerve +L/
tra%el" &etween, and "u$$lie", the internal o&li>ue and the tran"%er"u"
mu"cle" and $ierce" the internal and e)ternal o&li>ue
mu"cle" 5 cm a&o%e the e)ternal inguinal ring to "u$$ly "en"ation
o%er the lower anterior a&domen and $u&i" +"ee *ig. -</. The
ilioinguinal ner%e +L/ $a""e" through the internal o&li>ue mu"cle
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ;8
*igure -. Lym$hatic drainage of the male $el%i", $erineum,
and e)ternal genitalia.
Table 4:4(
omatic (er%e" of the Lower A&domen and el%i"
(H6FH (AMH 6IGI( ULIH
Iliohy$oga"tric L Motor "u$$ly to internal o&li>ue, tran"%er"u" mu"cle", "en"ation
o%er lower anterior
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a&dominal wall
Ilioinguinal L en"ation o%er anterior $u&i" +mon"/ and anterior "crotum or la&ia
Genitofemoral L, L Genital &ranch motor "u$$ly to crema"ter mu"cle "en"ation
to anterior "crotum
*emoral &ranch "en"ation to anterior thigh
*emoral L, L5, L; Motor "u$$ly to e)ten"or" of the #nee "en"ory to anterior thigh
&turator L, L5, L; Motor "u$$ly to adductor" of the thigh, "en"ation to medial
thigh
Lum&o"acral trun# L;, L< !oin" the "acral ner%e" to form the lum&o"acral $le)u"
that "u$$lie" motor and "en"ory
inner%ation to the lower e)tremitie"
o"terior femoral cutaneou" , 5 en"ation to $erineum, $o"terior "crotum, and
$o"terior thigh
udendal , 5, ; Motor to le%ator ani, mu"cle" of the urogenital dia$hragm, anal
and "triated urethral
"$hincter, "en"ation to the $erineum, "crotum, $eni"
el%ic "omatic e4erent" , 5, ; Motor "u$$ly to le%ator ani and "triated urethral
"$hincter
(er%i erigente" , 5, ; ara"ym$athetic '&er" from the "acral cord "u$$ly the
$el%ic %i"cera
to enter the inguinal canal laterally. It tra%el" anterior to the cord
and e)it" the e)ternal ring to $ro%ide "en"ation to the mon" $u&i"
and anterior "crotum or la&ia majora +"ee *ig". -< and -8/. The
genitofemoral ner%e +L, L/ $ierce" the $"oa" mu"cle to reach it"
anterior "urface in the retro$eritoneum and then tra%el" to the
$el%i" and "$lit" into genital and femoral &ranche". The latter "u$$lie"
"en"ation o%er the anterior thigh &elow the inguinal ligament.
The genital &ranch follow" the cord through the inguinal
canal, "u$$lie" the crema"ter mu"cle, and "u$$lie" "en"ation to the
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anterior "crotum.
*or mo"t of it" $el%ic cour"e, the femoral ner%e +L, L5, L;/
tra%el" within the "u&"tance of the $"oa" mu"cle and then e)it" it"
lateral "ide to $a"" under the inguinal ligament +*ig. -/. It "u$$lie"
"en"ation to the anterior thigh and motor inner%ation to the
e)ten"or" of the #nee. ,urin* a "soas hitch) sutures should
be "laced in the direction of the nerve #and the "soas
muscle <bers& to avoid nerve dama*e or entra"ment(
+etractor blades must not rest on the "soas muscle
because they can "roduce a femoral nerve "alsy) a $otentially
dangerou" "et&ac# after $el%ic "urgery. The lateral femoral
cutaneou" ner%e +L, L5/ may &e "een lateral to the $"oa" in the
iliacu" fa"cia.
The obturator nerve +L, L5, L;/ emerge" in the true $el%i"
from &eneath the $"oa" mu"cle, lateral to the internal iliac %e""el",
and $a""e" through the o&turator fo""a to the o&turator canal. In
the fo""a, it i" lateral and "u$erior to the o&turator %e""el" and
"urrounded &y the o&turator and internal iliac lym$h node".
Damage to thi" ner%e during $el%ic lym$hadenectomy wea#en"
the adductor" of the thigh.
The lumbosacral trun% #!=) !>& "asses into the true
"elvis behind the "soas and unites 'ith the ventral rami
*igure -. *emoral ner%e a" it relate" to the $"oa" mu"cle.
6etractor &lade" may com$re"" thi" ner%e to $roduce a femoral
ner%e $al"y. +*rom Burnett AL, Brendler CB. *emale neuro$athy
following major $el%ic "urgery etiology and $re%ention. ! Urol
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77;1<?5./
; SCTION I = Anatomy
although ner%e" to the ureter may join it directly a" it $a""e"
near&y. Fi"ceral a4erent and e4erent ner%e" tra%el on the %a"
deferen" to reach the te"ti" and e$ididymi" +"ee later di"cu""ion/.
The most caudal "ortion of the "elvic "le$us *ives rise
to the innervation of the "rostate and the im"ortant
cavernosal nerves +3al"h and Don#er, 7/. After $a""ing the
ti$" of the "eminal %e"icle", the"e ner%e" lie within lea%e" of the
lateral endo$el%ic fa"cia near it" juncture with, &ut out"ide,
Denon%illier" fa"cia +Le$or et al, 7</. They tra%el at the $o"terolateral
&order of the $ro"tate on the "urface of the rectum and are
lateral to the $ro"tatic ca$"ular arterie" and %ein" +"ee *ig. -</.
Becau"e the ner%e" are com$o"ed of multi$le '&er" not %i"i&le on
gro"" in"$ection, the"e %e""el" "er%e a" a "urgical landmar# for the
cour"e of the"e ner%e" +the neuro%a"cular &undle of 3al"h/. During
radical $ro"tatectomy, the ner%e" are mo"t %ulnera&le at the a$e)
of the $ro"tate, where they clo"ely a$$roach the $ro"tatic ca$"ule
at the <0 and 80ocloc# $o"ition". n reaching the mem&ranou"
urethra, the ner%e" di%ide into "u$er'cial &ranche", which tra%el
on the lateral "urface of the "triated urethral "$hincter at 50 and
70ocloc# $o"ition", and dee$ '&er", which $enetrate the "u&"tance
of thi" mu"cle and "end twig" to the &ul&ourethral gland". A" the
ner%e" reach the hilum of the $eni", they join to form one to three
di"crete &undle", related to the urethra at 0 and 0ocloc# $o"ition",
"u$er'cial to the ca%ernou" %ein" and dor"omedial to the
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ca%ernou" arterie" +*ig. -?/ +Lue et al, 7;1 Bre2a et al, 77/.
3ith the arterie", they $ierce the cor$ora ca%erno"a to "u$$ly the
erectile ti""ue +"ee later di"cu""ion/. mall '&er" al"o join the dor"al
ner%e" of the $eni" a" they cour"e di"tally. In the female, the
ner%e" to %e"ti&ular &odie" and cor$ora ca%erno"a of the clitori"
tra%el &etween the anterior %aginal wall and the &ladder in a""ociation
with the lateral %enou" $le)u"e".
P!VIC VISC+A
+ectum
The rectum &egin" with the di"a$$earance of the "igmoid me"entery
o$$o"ite the third "acral %erte&ra. Peritoneum continues
anteriorly over the u""er t'o thirds of the rectum as
the rectovesical "ouch in males and as the rectouterine
"ouch #of ,ou*las& in females +*ig. -81 "ee al"o *ig. -/.
Inci"ion of the anterior wall of thi" $eritoneal $ouch e)$o"e" the
"eminal %e"icle" &ehind the &ladder. Inferior to thi" $ouch, the
of the sacral se*mental nerves to form the sacral "le$us(
Thi" $le)u" lie" on the $el%ic "urface of the $iriformi" dee$ to the
endo$el%ic fa"cia and $o"terior to the internal iliac %e""el" +"ee *ig.
-?/. It lea%e" the $el%i" through the greater "ciatic foramen
immediately $o"terior to the "acro"$inou" ligament +where it may
&e injured during "acro"$inou" cul$o"u"$en"ion/ and "u$$lie"
motor and "en"ory inner%ation to the $o"terior thigh and lower
leg. An e)aggerated lithotomy $o"ition may "tretch thi" ner%e or
$lace $re""ure on it" $eroneal &ranch at the '&ular head to $roduce
foot dro$. el%ic and $erineal &ranche" of the "acral $le)u" include
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+/ the $o"terior femoral cutaneou" ner%e +, 5/, which, after
$a""ing through the greater "ciatic foramen, gi%e" an anterior
"en"ory &ranch to the $erineum and $o"terior "crotum +"ee *ig.
-/1 +/ the $udendal ner%e +, 5, ;/, which follow" the internal
$udendal artery to the $erineum +to &e di"cu""ed/1 +5/ the ner%i
erigente" +, 5, ;/ to the autonomic $le)u"1 and +;/ $el%ic
"omatic e4erent ner%e" from the %entral rami of , 5, and ;
+*ig. -5/. The latter ner%e" tra%el on the $el%ic "urface of the
le%ator ani in clo"e a""ociation with the rectum and $ro"tate and
are "e$arated from the $el%ic autonomic $le)u" &y the endo$el%ic
fa"cia. They "u$$ly the le%ator ani and e)tend anteriorly to the
"triated urethral "$hincter +Law"on, 78;1 %ara et al, 77;/.
Pelvic Autonomic Ple$us
The "resyna"tic sym"athetic cell bodies that "ro2ect to
the "elvic autonomic "le$us reside in the lateral column
of *ray matter in the last three thoracic and <rst t'o
lumbar se*ments of the s"inal cord( They reach the
"elvic "le$us by t'o "ath'ays8 #9& The su"erior hy"o*astric
"le$us i" formed &y "ym$athetic '&er" from the celiac
$le)u" and the 'r"t four lum&ar "$lanchnic ner%e" +*ig. -;/.
Anterior to the &ifurcation of the aorta, it di%ide" into two hy$oga"tric
ner%e" that enter the $el%i" medial to the internal iliac
%e""el", anterior to the "acrum, and dee$ to the endo$el%ic fa"cia.
+/ The $el%ic continuation" of the "ym$athetic trun#" $a"" dee$
to the common iliac %e""el" and medial to the "acral foramina and
fu"e in front of the coccy) at the ganglion im$ar +"ee *ig. -;/.
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Hach chain com$ri"e" four to '%e ganglia that "end &ranche"
anterolaterally to $artici$ate in the formation of the $el%ic $le)u".
Presyna"tic "arasym"athetic innervation arises from
the intermediolateral cell column of the sacral cord(
.ibers emer*e from the second) third) and fourth sacral
s"inal nerves as the "elvic s"lanchnic nerves #nervi eri*entes&
to 2oin the hy"o*astric nerves and branches from
the sacral sym"athetic *an*lia to form the inferior
hy"o*astric #"elvic& "le$us +"ee *ig. -;/. ome $el%ic $ara"ym$athetic
e4erent '&er" tra%el u$ the hy$oga"tric ner%e" to the
inferior me"enteric $le)u", where they $ro%ide $ara"ym$athetic
inner%ation to the de"cending and "igmoid colon.
The $el%ic $le)u" i" rectangular, a$$ro)imately ; to < cm long,
and it" mid$oint i" at the ti$" of the "eminal %e"icle" +chlegel and
3al"h, 78/. It i" oriented in the "agittal $lane on either "ide of
the rectum and $ierced &y the numerou" %e""el" going to and from
the rectum, &ladder, "eminal %e"icle", and $ro"tate +*ig. -</.
,ivision of these vessels #the so?called lateral "edicles
of the bladder and "rostate& ris%s in2ury to the "elvic
"le$us 'ith attendant "osto"erative im"otence +3al"h
and Don#er, 71 3al"h et al, 75/. The right and left com$onent"
of the $el%ic $le)u" communicate &ehind the rectum and
anterior and $o"terior to the %e"ical nec#. Branche" of the $el%ic
$le)u" follow $el%ic &lood %e""el" to reach the $el%ic %i"cera,
*igure -5. el%ic :oor "omatic e4erent ner%e" e)tending
anteriorly on the $el%ic "urface of the le%ator ani to "u$$ly thi"
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mu"cle and the "triated urethral "$hincter. +*rom Law"on !.
el%ic anatomy. I. el%ic :oor mu"cle". Ann 6 Coll urg Hngl
78;1<;<9./
5
Ileococcygeu"
Coccygeu"
u&oanali"
;
<
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ;7
*igure -;. ym$athetic and $ara"ym$athetic contri&ution" to the $el%ic
autonomic ner%ou" $le)u".
L<
5
;
el%ic "$lanchnic ner%e"
+$ara"ym$athetic"
from to ;/
acral "$lanchnic ner%e"
@y$oga"tric
ner%e
u$erior
hy$oga"tric
$le)u"
Inferior hy$oga"tric
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$le)u"
ym$athetic" de"cending from a&o%e el%ic $ara"ym$athetic" a"cending
anterior rectum i" related to it" fa"cial continuation +the rectogenital
or Denon%illier" fa"cia/ down to the le%el of the "triated urethral
"$hincter +"ee *ig". -;, -8, and -/. The rectum de"cri&e"
a gentle cur%e on the "acrum, coccy), and le%ator $late +"ee *ig.
-;/ and recei%e" inner%ation from the laterally $laced $el%ic
autonomic $le)u" and &lood "u$$ly from the "u$erior +from inferior
me"enteric/, middle +from internal iliac/, and inferior +from
internal $udendal/ rectal arterie".
The rectal wall i" com$o"ed of an inner layer of circular "mooth
mu"cle and a %irtually continuou" "heet of outer longitudinal
"mooth mu"cle deri%ed from the tenia of the colon. In it" lowe"t
$art, the rectum dilate" to form the rectal am$ulla. At the mo"t
inferior $ortion of the am$ulla, anterior '&er" of the longitudinal
mu"cle lea%e the rectum to join Denon%illier" fa"cia and the $o"terior
"triated urethral "$hincter in the a$e) of the $erineal &ody
+Broo#" et al, 99/. During $erineal $ro"tatectomy, the"e '&er",
the rectourethralis muscle) are 4 to 9@ mm thic% and
must be divided to *ain access to the "rostate +*ig. -7/.
The a$ice" of the $ro"tate and rectal am$ulla are in clo"e $ro)imity,
and rectal injurie" during radical $ro"tatectomy commonly
occur at thi" location. A" the rectourethrali" i" gi%en o4, the
rectum ma#e" a right0angle turn $o"teroinferiorly to e)it the $el%i"
at the anal canal +"ee *ig. -9/. The anatomy of the anal canal i"
con"idered with the $erineum.
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Pelvic 7reter
The ureter i" di%ided into a&dominal and $el%ic $ortion" &y the
common iliac artery. The "tructure of the ureter and it" a&dominal
cour"e are re%iewed in Cha$ter . Intrao$erati%ely, the ureter i"
identi'ed &y it" $eri"taltic wa%e" and i" readily found anterior to
the &ifurcation of the common iliac artery. At uretero"co$y, $ul"ation"
of thi" artery can &e "een in the $o"terior ureteral wall. The
ovarian vessels #infundibulo"elvic li*ament& cross the
iliac vessels anterior and lateral to the ureter) and dissection
of the ovarian vessels at the "elvic brim is a
common cause of ureteral in2ury +"ee *ig. -5/ +Daly and
@iggin", 7/. yeloureterogra$hy di"clo"e" a narrowing of the
ureter at the iliac %e""el", and ureteral calculi fre>uently &ecome
lodged at thi" location. Becau"e the ureter and iliac %e""el" re"t on
<9 SCTION I = Anatomy
*igure -<. Lateral %iew "howing the left $el%ic autonomic ner%ou" $le)u" and it"
relation to the $el%ic %i"cera. +*rom chlegel (, 3al"h
C. (euroanatomical a$$roach to radical cy"to$ro"tatectomy with $re"er%ation of
"e)ual function. ! Urol 7815;95./
ro"tate
Urethra
el%ic
dia$h
(euro%a"cular
&undle
6ectum
el%ic nn.
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+$ara"ym$athetic/
a c
r u
m
el%ic
$le)u"
@y$oga". n.
+"ym$athetic/
Inf. %e"ical
$edicle
eminal
%e"icle
u$. %e"ical
$edicle
Ur
Fa"
Bl
*igure -?. Dor"al $enile arterie", %ein", and ner%e". +*rom @inman * !r. Atla" of
uro"urgical anatomy. hiladel$hia 3B aunder" 775.
$. ;;<./
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia <
*igure -8. agittal "ection through the $ro"tatic and mem&ranou" urethra,
demon"trating the midline relation" of the $el%ic "tructure".
+*rom @inman * !r. Atla" of uro"urgical anatomy. hiladel$hia 3B aunder"1 775.
$. 5<?./
6etro$u&ic "$ace
eritoneum
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Bladder &a"e
6. urethral ori'ce
re$ro"tatic urethra
ro"tate
Am$ulla of %a" deferen"
6ecto%e"ical $ouch
Denon%illier" f.
Anterior lamella
o"terior lamella
Anterior rectal wall
Internal anal
"$hincter
H)ternal anal
"$hincter
Central tendon
ro"tatic
"triated "$hincter
Mem&ranou"
urethral "$hincter
Bul&o"$ongio"u" m.
Colle" f.
Cor$u" "$ongio"um
ro"tatic %enou" $le)u"
Buc# f.
Dee$ dor"al %., $eni"
Cor$u" ca%erno"um
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u&ic
"ym$hy"i"
*igure -. Median "agittal "ection of the female $el%i",
"howing the $otential "$ace" &etween the $el%ic organ". The
$o"terior two third" of the %agina lie" nearly hori2ontal and re"t"
with the uterine cer%i) on the rectum, which i" in turn "u$$orted
&y the $o"terior $ortion of le%ator ani +the le%ator $late, not
"hown/. 6F, recto%aginal "$ace, the anterior wall i" formed &y
the recto%aginal +Denon%illier"/ fa"cia1 Fe, "u$ra%aginal "e$tum,
the fu"ion &etween the &ladder and cer%i)1 FC, %e"icocer%ical
"$ace1 FF, %e"ico%aginal "$ace. +*rom (ichol" D@, 6andall CL.
Faginal "urgery. 5rd ed. Baltimore 3illiam" J 3il#in"1 77. $. 5;./
Fe
FC
FF
6F
the arcuate line, the ureter i" "u&ject to com$re""ion and o&"truction
&y the gra%id uteru" and &y ma""e" within the true $el%i".
The ureter" come within < cm of each other a" they cro"" the
iliac %e""el". n entering the $el%i", they di%erge widely along the
$el%ic "ide wall" toward the i"chial "$ine". The ureter tra%el" on
the anterior "urface of the internal iliac %e""el" and i" related laterally
to the &ranche" of the anterior trun#. (ear the i"chial "$ine,
the ureter turn" anteriorly and medially to reach the &ladder.
In men) the anteromedial "urface of the ureter i" co%ered &y
$eritoneum, and the ureter i" em&edded in retro$eritoneal connecti%e
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ti""ue, which %arie" in thic#ne"" +"ee *ig. -5/. A" the
ureter cour"e" medially, it i" cro""ed anteriorly &y the %a" deferen"
and run" with the inferior %e"ical arterie", %ein", and ner%e" in the
lateral %e"ical ligament". Fiewed from the $eritoneal "ide, the
ureter i" ju"t lateral and dee$ to the rectogenital fold. In women,
the ureter 'r"t run" $o"terior to the o%ary and then turn" medially
to run dee$ to the &a"e of the &road ligament &efore entering a
loo"e connecti%e ti""ue tunnel through the "u&"tance of the cardinal
ligament +"ee *ig. -5/. A" in the male, the ureter can &e
found "lightly lateral and dee$ to the rectouterine fold" of $eritoneum.
It i" cro""ed anteriorly &y the uterine artery and can &e
injured during hy"terectomy. A" it $a""e" in front of the %agina,
it cro""e" .< cm anterior and lateral to the uterine cer%i). The
ureter can &e injured at thi" le%el during hy"terectomy, re"ulting
in a uretero%aginal '"tula. The ureter cour"e" to ; cm on the
anterior %aginal wall to reach the &ladder. cca"ionally, a "tone
lodged in the di"tal ureter can &e $al$ated through the anterior
%aginal wall. The intramural ureter i" di"cu""ed with the &ladder.
The $el%ic ureter recei%e" a&undant &lood "u$$ly from the
common iliac artery and mo"t &ranche" of the internal iliac artery.
The inferior %e"ical and uterine arterie" u"ually "u$$ly the ureter
with it" large"t $el%ic &ranche". Blood su""ly to the "elvic
ureter enters laterally6 thus the "elvic "eritoneum should
be incised only medial to the ureter( Intramural %e""el" of
the ureter run within the ad%entitia and generally follow one of
two $attern". In a$$ro)imately 8<K of "$ecimen", longitudinal
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%e""el" run the length of the ureter and are formed &y ana"tomo"e"
of "egmental ureteral %e""el". In the remaining ureter", the %e""el"
form a 'ne interconnecting me"h +$le)iform/ with le"" collateral
:ow +ha'#, 78/. Therefore $rimary re$air of injurie" to the
$el%ic ureter fare $oorly and are more $rone to "tricture formation
+@inman, 775/. Lym$hatic drainage of the $el%ic ureter i" to the
e)ternal, internal, and common iliac node". athologic enlargement
of the common and internal iliac node" can encroach on
and o&"truct the ureter.
The $el%ic ureter ha" rich adrenergic and cholinergic autonomic
inner%ation deri%ed from the $el%ic $le)u". The functional
< SCTION I = Anatomy
continuity with the &ladder "er%e" a" a &acterial re"er%oir or re"ult"
in an um&ilical urinary '"tula.
The "u$erior "urface of the &ladder i" co%ered &y $eritoneum.
Anteriorly, the $eritoneum "wee$" gently onto the anterior
a&dominal wall +"ee *ig. -5/. 3ith di"tention, the &ladder ri"e"
out of the true $el%i" and "e$arate" the $eritoneum from the
anterior a&dominal wall. It i" therefore $o""i&le to $erform a
"u$ra$u&ic cy"to"tomy without ri"#ing entry into the $eritoneal
ca%ity. o"teriorly, the $eritoneum $a""e" to the le%el of the
"eminal %e"icle" and meet" the $eritoneum on the anterior rectum
to form the recto%e"ical "$ace.
Anteroinferiorly and laterally, the bladder is cushioned
from the "elvic side 'all by retro"ubic and "erivesical
fat and loose connective tissue( This "otential s"ace #of
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+et/ius& may be entered anteriorly by dividin* the transversalis
fascia and "rovides access to the "elvic viscera
as far "osteriorly as the iliac vessels and ureters +"ee *ig.
-/. The &ladder &a"e i" related to the "eminal %e"icle", am$ullae
of the %a" deferentia, and terminal ureter. The &ladder nec#,
located at the internal urethral meatu", re"t" 5 to ; cm &ehind the
mid$oint of the "ym$hy"i" $u&i". It i" 'rmly ')ed &y the $el%ic
fa"ciae +"ee earlier di"cu""ion/ and &y it" continuity with the $ro"tate1
it" $o"ition change" little with %arying condition" of the
&ladder and rectum.
In the female) the "eritoneum on the su"erior surface
of the bladder is re0ected over the uterus to form the
vesicouterine "ouch and then continues "osteriorly over
"igni'cance of thi" inner%ation i" unclear, ina"much a" the ureter
continue" to contract $eri"taltically after dener%ation. A4erent
neural '&er" tra%el through the $el%ic $le)u" and account for the
%i"ceral >uality of referred $ain from ureteral irritation or acute
o&"truction.
Bladder
+elationshi"s
When <lled) the bladder has a ca"acity of a""ro$imately
>@@ m! and a""ume" an o%oid "ha$e. The em$ty &ladder i" tetrahedral
and i" de"cri&ed a" ha%ing a "u$erior "urface with an a$e)
at the urachu", two inferolateral "urface", and a $o"teroinferior
"urface or &a"e with the &ladder nec# at the lowe"t $oint +"ee *ig.
-8/.
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The urachus anchors the bladder to the anterior
abdominal 'all +"ee *ig. -/. There i" a relati%e $aucity of
&ladder wall mu"cle at the $oint of attachment of the urachu",
$redi"$o"ing to di%erticula formation. The urachu" i" com$o"ed
of longitudinal "mooth mu"cle &undle" deri%ed from the &ladder
wall. (ear the um&ilicu", it &ecome" more '&rou" and u"ually
fu"e" with one of the o&literated um&ilical arterie". Urachal %e""el"
run longitudinally, and the end" of the urachu" mu"t &e ligated
when it i" di%ided. An e$ithelium0lined lumen u"ually $er"i"t"
throughout life and uncommonly gi%e" ri"e to aggre""i%e urachal
adenocarcinoma" +Begg, 759/. In rare in"tance", luminal
*igure -7. Mu"cle" and "u$er'cial fa"ciae of the male $erineum. +*rom @inman *
!r. Atla" of uro"urgical anatomy. hiladel$hia 3B
aunder"1 775. $. 7./
Cor$u"
ca%erno"um
Cor$u"
"$ongio"um
I"chioca%erno"u" m.
u&ic ramu"
Inferior fa"cia of
urogenital dia$hragm
Colle" f.
u$er'cial tran"%er"e
$erineal m.
I"chial tu&ero"ity
u&ococcygeu" m.
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Le%ator ani m.
acrotu&erou" l.
Coccygeu" m.
Coccy)
acrum
#in
u$er'cial $enile f.
Buc# f.
Bul&o"$ongio"u" m.
Colle" f.
major leaf
ctotal
darto"
Te"ti"
erineal &ody
6ectourethrali"
H)ternal
anal "$hincter
u&cutaneou"
u$er'cial
Dee$
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia <5
Near the bladder nec%) the detrusor muscle is clearly
se"arable into the three layers described earlier( 3ere)
the smooth muscle is mor"holo*ically and "harmacolo*ically
distinct from the remainder of the bladder
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because the lar*e?diameter muscle fascicles are re"laced
by much <ner <bers( The structure of the bladder nec%
a""ears to di;er bet'een men and 'omen( In men) radially
oriented inner lon*itudinal <bers "ass throu*h the
internal meatus to become continuous 'ith the inner
lon*itudinal layer of smooth muscle in the urethra(
The middle layer forms a circular "re"rostatic s"hincter
that i" re"$on"i&le for continence at the le%el of the &ladder
nec# +*ig. -5 on the H)$ert Con"ult we&"ite/. The &ladder wall
$o"terior to the internal urethral meatu" and the anterior '&romu"cular
"troma of the $ro"tate form a continuou" ringli#e "tructure
at the &ladder nec# +Broo#" et al, 77/. The fact that $erfect
continence can &e maintained in men in whom the "triated urethral
"$hincter i" de"troyed atte"t" to the eOcacy of thi" "$hincter
+3aterhou"e et al, 785/. Thi" mu"cle i" richly inner%ated &y
adrenergic '&er", which, when "timulated, $roduce clo"ure of the
&ladder nec# +Uhlenhuth, 7<5/. Damage to the "ym$athetic
ner%e" to the &ladder, a" a re"ult of dia&ete" mellitu" or retro$eritoneal
lym$h node di""ection for te"ti" cancer, can cau"e retrograde
ejaculation.
The outer lon*itudinal <bers are thic%est "osteriorly
at the bladder base( In the midline, they in"ert into the a$e)
of the trigone and intermi) with the "mooth mu"cle of the $ro"tate
to $ro%ide a "trong trigonal &ac#ing. Laterally, the '&er" from
thi" $o"terior "heet $a"" anteriorly and fu"e to form a loo$ around
the &ladder nec# +"ee *ig. -59/. Thi" loo$ i" thought to $artici$ate
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in continence at the &ladder nec#. n the lateral and anterior
"urface" of the &ladder, the longitudinal '&er" are not a" well
the uterus as the rectouterine "ouch +"ee *ig. -5/. The
%agina and uteru" inter%ene &etween the &ladder and the rectum
"o that the &a"e of the &ladder and urethra re"t on the anterior
%aginal wall. Becau"e the anterior %aginal wall i" 'rmly attached
laterally to the le%ator ani, contraction of the $el%ic dia$hragm
+e.g., during increa"e" in intra0a&dominal $re""ure/ ele%ate" the
&ladder nec# and draw" it anteriorly. In many women with "tre""
incontinence, the &ladder nec# dro$" &elow the $u&ic "ym$hy"i".
In infant", the true $el%i" i" "hallow and the &ladder nec# i" le%el
with the u$$er &order of the "ym$hy"i". The &ladder i" a true
intra0a&dominal organ that can $roject a&o%e the um&ilicu" when
full. By $u&erty, the &ladder ha" migrated to the con'ne" of the
dee$ened true $el%i".
Structure
The internal surface of the bladder is lined 'ith transitional
e"ithelium) which a$$ear" "mooth when the &ladder i"
full &ut contract" into numerou" fold" when the &ladder em$tie".
Thi" urothelium i" u"ually "i) cell" thic# and re"t" on a thin &a"ement
mem&rane. Dee$ to thi", the lamina $ro$ria form" a relati%ely
thic# layer of '&roela"tic connecti%e ti""ue that allow"
con"idera&le di"tention. Thi" layer i" tra%er"ed &y numerou" &lood
%e""el" and contain" "mooth mu"cle '&er" collected into a $oorly
de'ned mu"culari" muco"a. Beneath thi" layer lie" the "mooth
mu"cle of the &ladder wall. The relati%ely large mu"cle '&er" form
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&ranching, interlacing &undle" loo"ely arranged into inner longitudinal,
middle circular, and outer longitudinal layer" +*ig. -59/.
@owe%er, in the u$$er a"$ect of the &ladder, the"e layer" are clearly
not "e$ara&le, and any one '&er can tra%el &etween each of the
layer", change orientation, and &ranch into longitudinal and circular
'&er". Thi" me"hwor# of detru"or mu"cle i" ideally "uited for
em$tying the "$herical &ladder.
*igure -59. Di""ection of the male
&ladder. , o"terior outer
longitudinal detru"or, which form"
the &ac#ing of the ureter" +folded
&ac#/1 a, $o"terolateral $ortion of
the outer longitudinal mu"cle
forming a loo$ around the anterior
&ladder nec#1 ;P, , and , middle
circular layer &ac#ing the trigone1
5 and 5a, lateral $edicle of the
$ro"tate. +*rom Uhlenhuth H.
ro&lem" in the anatomy of the
$el%i". hiladel$hia !B Li$$incott1
7<5. $. 8./
<; SCTION I = Anatomy
*igure -5. *emale &ladder and "triated urethral "$hincter. a, Diagram of "triated
urethral "$hincter "howing di"$o"ition of the mu"cle
'&er". , The $ro)imal third of the "$hincter encircle" the urethra entirely. , The
middle &undle" "urround the urethra in front and $a"" o4
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the lateral "ide" to &lend with the %aginal wall +com$re""or urethrae/. 5, The di"tal
$ortion "urround" the urethra and %agina together and
ha" &een called the urethrovaginal sphincter. The &ul&oca%erno"u" al"o act" a" a
"$hincter around the %aginal %e"ti&ule. &, Urethral
"$hincter in it" entirety. The relation"hi$ of the $el%ic %i"cera i" "hown. Interlacing
detru"or '&er" are al"o demon"trated. c, o"terolateral
outer longitudinal detru"or mu"cle, loo$ing anterior to the &ladder nec#. Inner
longitudinal "mooth mu"cle '&er" run the length of the
urethra, dee$ to the "triated "$hincter. d, Cro"" "ection of the urethra, "howing
thic#, highly %a"culari2ed lamina $ro$ria and folded
muco"a, which act a" a urethral "eal. Longitudinal "mooth mu"cle "urround" the
lamina $ro$ria. +riginal art in the Ma) BrQdel Archi%e",
De$artment of Art a" A$$lied to Medicine, The !ohn" @o$#in" Uni%er"ity chool of
Medicine./
de%elo$ed. ome anterior '&er" cour"e forward to join the $u&o$ro"tatic
ligament" in men and the $u&ourethral ligament" in
women. The"e '&er" contri&ute "mooth mu"cle to the"e "u$$ort"
and are "$eculated to contri&ute to &ladder nec# o$ening during
micturition +DeLancey, 77/.
At the female bladder nec%) the inner lon*itudinal
<bers conver*e radially to "ass do'n'ard as the inner
lon*itudinal layer of the urethra) a" de"cri&ed earlier. The
middle circular layer doe" not a$$ear to &e a" ro&u"t a" that of the
male, and "e%eral author" ha%e denied it" e)i"tence altogether
+Go"ling, 787, 7<1 3illiam" et al, 77/. Although "e%eral other
in%e"tigator" ha%e noted an anterior loo$ of e)ternal longitudinal
mu"cle +*ig. -5/, the author" ju"t cited deny the e)i"tence of thi"
"tructure a" well. They maintain in"tead that the e)ternal '&er"
$a"" o&li>uely and longitudinally down the urethra to $artici$ate
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in forming the inner longitudinal layer of "mooth mu"cle. 6egardle"",
the female &ladder nec# di4er" "tri#ingly from the male in
$o""e""ing little adrenergic inner%ation. In addition, it" "$hincteric
function i" limited1 in <9K of continent women, urine enter"
the $ro)imal urethra during a cough +Fer"i et al, 7?/.
7reterovesical unction and the Tri*one
As the ureter a""roaches the bladder) its s"irally oriented
mural smooth muscle <bers become lon*itudinal(
T'o to cm from the bladder) a <bromuscular sheath
#of Waldeyer& e$tends lon*itudinally over the ureter and
follo's it to the tri*one +Tanagho, 77/. The ureter $ierce"
the &ladder wall o&li>uely, tra%el" .< to cm, and terminate" at
the ureteral ori'ce +*ig. -55/. A" it $a""e" through a hiatu" in the
detru"or +intramural ureter/, it i" com$re""ed and narrow" con"idera&ly.
Thi" i" a common "ite in which ureteral "tone" &ecome
im$acted. The intra%e"ical $ortion of the ureter lie" immediately
&eneath the &ladder urothelium and therefore i" >uite $liant1 it i"
&ac#ed &y a "trong $late of detru"or mu"cle. 3ith &ladder 'lling,
thi" arrangement i" thought to re"ult in $a""i%e occlu"ion of the
ureter, li#e a :a$ %al%e. Indeed, re:u) doe" not occur in fre"h
cada%er" when the &ladder i" 'lled +Thom"on et al, 77;/. Fe"icoureteral
re:u) i" thought to re"ult from in"uOcient "u&muco"al
ureteral length and $oor detru"or &ac#ing. Chronic increa"e" in
intra%e"ical $re""ure re"ulting from &ladder outlet o&"truction can
cau"e herniation of the &ladder muco"a through the wea#e"t $oint
of the hiatu" a&o%e the ureter and $roduce a @utch di%erticulumN
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and re:u) +@utch et al, 7?/.
The trian*le of smooth urothelium bet'een the t'o
ureteral ori<ces and the internal urethral meatus is
referred to as the trigone of the bladder +"ee *ig. -55/. The
'ne longitudinal "mooth mu"cle '&er" from each ureter fan out
o%er the &a"e of the &ladder to form a triangular "heet of mu"cle
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia <<
%e"icle $le)u" and drain into the internal iliac %ein. Lym$hatic"
from the lamina $ro$ria and mu"culari" drain to channel" on the
&ladder "urface, which run with the "u$er'cial %e""el" within the
thin %i"ceral fa"cia. mall $ara%e"ical lym$h node" can &e found
along the "u$er'cial channel". The &ul# of the lym$hatic drainage
$a""e" to the e)ternal iliac lym$h node" +"ee *ig. -/. ome
anterior and lateral drainage may go through the o&turator and
internal iliac node", wherea" $ortion" of the &ladder &a"e and
trigone may drain into the internal and common iliac grou$".
Bladder Innervation
Autonomic e;erent <bers from the anterior "ortion of
the "elvic "le$us #the vesical "le$us& "ass u" the lateral
and "osterior li*aments to innervate the bladder( The
bladder 'all is richly su""lied 'ith "arasym"athetic
choliner*ic nerve endin*s and ha" a&undant $o"tganglionic
cell &odie". $ar"e "ym$athetic inner%ation of the &ladder ha"
&een $ro$o"ed to mediate detru"or rela)ation &ut $ro&a&ly lac#"
functional "igni'cance. A "e$arate nonadrenergic, noncholinergic
+(A(C/ com$onent of the autonomic ner%ou" "y"tem $artici$ate"
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ureter, the "u$er'cial trigonal mu"cle anchor" the ureter to the
&ladder. During ureteral reim$lantation, thi" mu"cle i" tented u$
and di%ided in order to gain acce"" to the "$ace &etween 3aldeyer
"heath and the ureter. In thi" "$ace, only loo"e '&rou" and mu"cular
connection" are found. Thi" anatomic arrangement hel$"
$re%ent re:u) during &ladder 'lling &y ')ing and a$$lying ten"ion
to the ureteral ori'ce. A" the &ladder 'll", it" lateral wall tele"co$e"
outward on the ureter, there&y increa"ing intra%e"ical ureteral
length +@utch et al, 7?/.
The urothelium o%erlying the mu"cular trigone i" u"ually only
three cell" thic# and adhere" "trongly to the underlying mu"cle &y
a den"e lamina $ro$ria. During 'lling and em$tying of the &ladder,
thi" muco"al "urface remain" "mooth.
Bladder Circulation
In addition to the vesical branches) the bladder may be
su""lied by any ad2acent artery arisin* from the internal
iliac artery( .or convenience) sur*eons refer to the
vesical blood su""ly as the lateral and posterior "edicles ,
which, when the &ladder i" a$$roached from the recto%e"ical
"$ace, are lateral and $o"teromedial to the ureter", re"$ecti%ely.
The"e $edicle" are the lateral and $o"terior %e"ical ligament" in
the male and $art of cardinal and utero"acral ligament" in the
female +"ee *ig. -5/. The %ein" of the &ladder coale"ce into the
*igure -55. (ormal uretero%e"ical junction and trigone.
A) ection of the &ladder wall $er$endicular to the ureteral
hiatu" "how" the o&li>ue $a""age of the ureter through the
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detru"or and al"o "how" the "u&muco"al ureter with it"
detru"or &ac#ing. 3aldeyer "heath "urround" the $re%e"ical
ureter and e)tend" inward to &ecome the dee$ trigone.
B) 3aldeyer "heath continue" in the &ladder a" the dee$
trigone, which i" ')ed at the &ladder nec#. mooth mu"cle
of the ureter form" the "u$er'cial trigone and i" anchored at
the %erumontanum. +*rom Tanagho HA, ugh 6CB. The
anatomy and function of the uretero%e"ical junction. Br !
Urol 7?515<<./
<? SCTION I = Anatomy
and &lend with the '&romu"cular ti""ue of the ca$"ule. A" mentioned,
the middle circular and inner longitudinal mu"cle" e)tend
down the $ro"tatic urethra a" a $re$ro"tatic "$hincter. A" with the
a$e), no true ca$"ule "e$arate" the $ro"tate from the &ladder. In
"urgically re"ected $ro"tate carcinoma", thi" $eculiar anatomic
arrangement can ma#e inter$retation of the"e margin" diOcult
and ha" led "ome $athologi"t" to $ro$o"e that the $ro"tate doe"
not $o""e"" a true ca$"ule +H$"tein, 77/.
Structure
The "rostate is com"osed of a""ro$imately @D *landular
elements and @D <bromuscular stroma( The "troma
i" continuou" with ca$"ule and i" com$o"ed of collagen and a&undant
"mooth mu"cle. It encircle" and in%e"t" the gland" of the
$ro"tate and contract" during ejaculation to e)$re"" $ro"tatic
"ecretion" into the urethra.
The urethra runs the len*th of the "rostate and is
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usually closest to its anterior surface( It is lined by transitional
e"ithelium) which may e)tend into the $ro"tatic duct".
The urothelium i" "urrounded &y an inner longitudinal and an
outer circular layer of "mooth mu"cle. A urethral cre"t $roject"
inward from the $o"terior midline, run" the length of the $ro"tatic
urethra, and di"a$$ear" at the "triated "$hincter +*ig. -5</. To
either "ide of thi" cre"t, a groo%e i" formed +$ro"tatic "inu"e"/ into
which all glandular element" drain +Mc(eal, 78/. At it" mid$oint,
the urethra turn" a$$ro)imately 5< degree" anteriorly, &ut
thi" angulation can %ary from 9 to 79 degree" +"ee *ig". -8, -5,
-5?, and -58/. Thi" angle di%ide" the $ro"tatic urethra into
$ro)imal +$re$ro"tatic/ and di"tal +$ro"tatic/ "egment" that are
Prostate
+elationshi"s
The normal $ro"tate weigh" g1 mea"ure" 5 cm in length, ; cm
in width, and cm in de$th1 and i" tra%er"ed &y the $ro"tatic
urethra +"ee *ig. -8/. Although o%oid, the "rostate is referred
to as havin* anterior) "osterior) and lateral surfaces)
'ith a narro'ed a"e$ inferiorly and a broad base su"eriorly
that i" contiguou" with the &a"e of the &ladder. It i"
enclo"ed &y a ca$"ule com$o"ed of collagen, ela"tin, and a&undant
"mooth mu"cle. o"teriorly and laterally, thi" ca$"ule ha" an
a%erage thic#ne"" of 9.< mm, although it may &e $artially tran"gre""ed
&y normal gland". Micro"co$ic &and" of "mooth mu"cle
e)tend from the $o"terior "urface of the ca$"ule to fu"e with
Denon%illier" fa"cia. Loo"e areolar ti""ue de'ne" a thin $lane
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&etween Denon%illier" fa"cia and the rectum. n the anterior and
anterolateral "urface" of the $ro"tate, the ca$"ule &lend" with the
%i"ceral continuation of endo$el%ic fa"cia. Toward the a$e), the
$u&o$ro"tatic ligament" e)tend anteriorly to ') the $ro"tate to
the $u&ic &one. The "u$er'cial &ranch of the dor"al %ein lie"
out"ide thi" fa"cia in the retro$u&ic fat and $ierce" it to drain into
the dor"al %ein com$le).
Laterally, the $ro"tate i" cradled &y the $u&ococcygeal $ortion
of le%ator ani and i" directly related to it" o%erlying endo$el%ic
fa"cia +"ee *ig". - and -9/. Below the juncture of the $arietal
and %i"ceral endo$el%ic fa"cia +arcu" tendineu" fa"cia $el%i"/, the
$el%ic fa"cia and $ro"tate ca$"ule "e$arate and the "$ace &etween
them i" 'lled &y fatty areolar ti""ue and the lateral di%i"ion" of the
dor"al %ein com$le). During a radical retro$u&ic $ro"tatectomy,
the endo$el%ic fa"cia "hould &e di%ided lateral to the arcu" tendineu"
fa"cia $el%i" to a%oid injury to the %enou" com$le).
In the $roce"", the endo$el%ic fa"cia o%erlying the le%ator ani i"
actually $eeled o4 the mu"cle and di"$laced medially with the
$ro"tate. Although thi" i" truly a $arietal endo$el%ic fa"cia, it i"
commonly referred to a" the lateral $ro"tatic fa"ciaN +Myer",
77;/. A" mentioned earlier, the ca%erno"al ner%e" run $o"terolateral
to the $ro"tate in the "u&"tance of the $arietal $el%ic fa"cia
+lateral $ro"tatic fa"cia/. Thu" to $re"er%e the"e ner%e", thi" fa"cia
mu"t &e inci"ed lateral to the $ro"tate and anterior to the neuro%a"cular
&undle +3al"h et al, 75/. Therefore an under"tanding
of the fa"cial layer" that o%erlie the $ro"tate i" crucial in the
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$erformance of an accurate ner%e0"$aring radical $ro"tatectomy
+*ig -5;/.
6ecently, with the ado$tion of ro&otic and la$aro"co$ic radical
$ro"tatectomy techni>ue", there ha" &een a renewed intere"t in
the de"cri$tion of the"e fa"cial layer" with re"$ect to the neuro%a"cular
&undle &ecau"e the"e layer" may &e &etter %i"uali2ed with
the magni'cation a4orded &y the"e techni>ue" +Tewari et al,
99?/. Better de'nition of the lateral $ro"tatic fa"ciaN at the le%el
of the $ro"tatic $edicle" ha" &ecome nece""ary in $re"er%ing
the ca%erno"al ner%e" &ecau"e the di""ection i" often $erformed
antegrade in the"e techni>ue". Anatomic "tudie" ha%e re%ealed
ner%e &undle" that cour"e along the $ro"tate laterally and anteriorly
to the ner%e", commonly referred to a" the neurovascular
bundle +Hichel&erg et al, 9981 6aychaudhuri and Cahill, 99/.
3hether the"e ner%e" contri&ute to erectile function remain"
contro%er"ial.
The a"e$ of the "rostate is continuous 'ith the striated
urethral s"hincter +"ee *ig. -;/. @i"tologically normal
$ro"tatic gland" can &e found to e)tend into the "triated mu"cle
with no inter%ening '&romu"cular "troma or ca$"ule.N At the
&a"e of the $ro"tate, outer longitudinal '&er" of the detru"or fu"e
*igure -5;. Cro"" "ection of $ro"tate with $ro"tatic fa"cial layer"
outlined including the lateral $ro"tatic fa"cia +L*/, endo$el%ic
fa"cia +H*/, le%ator ani fa"cia +LA*/, Denon%illier" fa"cia +D*/,
anterior lamina of Denon%illier" fa"cia +AD*/, $o"terior lamina of
Denon%illier" fa"cia, neuro%a"cular &undle +(FB/, and lateral
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ner%e" +(/. +*rom 3al2 !, Graefen M, @uland @. Ba"ic $rinci$le"
of anatomy for o$timal "urgical treatment of $ro"tate cancer.
3orld ! Urol 9981<5-./
6ectum
ro"tate
H*
LA*
(FB
D*
D*
AD*
(
(
(
L*
Le%ator ani
mu"cle
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia <8
*igure -5<. o"terior wall of the male urethra. +*rom An"on B!,
McFay CB. urgical anatomy. ?th ed. hiladel$hia 3B aunder"1
7;. $. 55./
Trigonum %e"icale
ar" $ro"tatica
urethrae
ar"
mem&ranacea
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urethrae
Lacunae urethrale"
*o""a na%iculari"
Glan" $eni"
ri'cium
e)ternum
urethrae
ri'cium ureteri"
Annulu" urethrali"
Cri"ta urethrali"
Colliculu" "eminali" +%erumontanum/
ro"tata
Cri"ta urethrali"
licae colliculi
ri'icium ducti e)cretorii
glandulae
&ul&ourethrali" +Cow$eri/
ar" ca%erno"a
urethrae
functionally and anatomically di"crete +Mc(eal, 78, 7/. In
the $ro)imal "egment, the circular "mooth mu"cle i" thic#ened to
form the in%oluntary internal urethral +$re$ro"tatic/ "$hincter
de"cri&ed earlier. mall $eriurethral gland", lac#ing $eriglandular
"mooth mu"cle, e)tend &etween the '&er" of the longitudinal
"mooth mu"cle to &e enclo"ed &y the $re$ro"tatic "$hincter.
Although the"e gland" con"titute le"" than K of the "ecretory
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element" of the $ro"tate, they can contri&ute "igni'cantly to $ro"tatic
%olume in older men a" one of the "ite" of origin of &enign
$ro"tatic hy$ertro$hy.
Beyond to the urethral an*le) all ma2or *landular elements
of the "rostate o"en into the "rostatic urethra(
The urethral cre"t widen" and $rotrude" from the $o"terior wall
a" the %erumontanum +"ee *ig". -5<, -58, and -5/. The "mall
"litli#e ori'ce of the $ro"tatic utricle i" found at the a$e) of the
%erumontanum and may &e %i"uali2ed cy"to"co$ically. The utricle
i" a ?0mm mSllerian remnant in the form of a "mall "ac that $roject"
u$ward and &ac#ward into the "u&"tance of the $ro"tate. In
male" with am&iguou" genitalia, it may form a large di%erticulum
that $rotrude" from the $o"terior "ide of the $ro"tate. To either
"ide of the utricular ori'ce, the two "mall o$ening" of the ejaculatory
duct" may &e found. The ejaculatory duct" form at the juncture
of the %a" deferen" and "eminal %e"icle" and enter the $ro"tate
&a"e, where it fu"e" with the &ladder. They cour"e nearly cm
through the $ro"tate in line with the di"tal $ro"tatic urethra and
are "urrounded &y circular "mooth mu"cle +"ee *ig. -5?1 "ee al"o
*ig". -8 and -5/.
In general, the *lands of the "rostate are tubuloalveolar
'ith relatively sim"le branchin* and are lined 'ith
sim"le cuboidal or columnar e"ithelium( Scattered
neuroendocrine cells) of un%no'n function) are found
bet'een the secretory cells( Beneath the e"ithelial cells)
0attened basal cells line each acinus( Hach acinu" i" "urrounded
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&y a thin layer of "tromal "mooth mu"cle and connecti%e
ti""ue.
The glandular element" of the $ro"tate ha%e &een di%ided into
di"crete 2one", di"tingui"hed &y the location of their duct" in the
urethra, &y their di4ering $athologic le"ion", and, in "ome ca"e",
&y their em&ryologic origin +"ee *ig. -5?/. The"e 2one" can &e
demon"trated clearly with tran"rectal ultra"onogra$hy +*ig -57/.
At the an*le dividin* the "re"rostatic and "rostatic
urethra) the ducts of the transition /one arise and "ass
beneath the "re"rostatic s"hincter to travel on its lateral
and "osterior sides( (ormally, the tran"ition 2one account" for
<K to 9K of the glandular ti""ue of the $ro"tate. A di"crete '&romu"cular
&and of ti""ue "e$arate" the tran"ition 2one from the
remaining glandular com$artment" and may &e %i"uali2ed at
tran"rectal
ultra"onogra$hy of the $ro"tate. The tran"ition 2one
commonly gi%e" ri"e to &enign $ro"tatic hy$ertro$hy, which
e)$and" to com$re"" the '&romu"cular &and into a "urgical
ca$"ule "een at enucleation of an adenoma. It i" e"timated that
9K of adenocarcinoma" of the $ro"tate originate in thi" 2one.
The ducts of the central /one arise circumferentially
around the o"enin*s of the e2aculatory ducts( Thi" 2one
con"titute" <K of the glandular ti""ue of the $ro"tate and e)$and"
in a cone "ha$e around the ejaculatory duct" to the &a"e of the
&ladder. The gland" are "tructurally and immunohi"tochemically
di"tinct from the remaining $ro"tatic gland" +which &ranch
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directly from the urogenital "inu"/, which ha" led to the "ugge"tion
that they are of wolOan origin +Mc(eal, 7/. In #ee$ing
with thi" "ugge"tion, only K to <K of adenocarcinoma" ari"e in
the central 2one, although it may &e in'ltrated &y cancer" from
adjacent 2one".
The "eri"heral /one ma%es u" the bul% of the "rostatic
*landular tissue #@D& and covers the "osterior and
lateral as"ects of the *land( Its ducts drain into the "rostatic
sinus alon* the entire len*th of the #"osts"hincteric&
"rostatic urethra( Seventy "ercent of "rostatic
cancers arise in this /one) and it is the /one most commonly
a;ected by chronic "rostatitis(
U$ to one third of the $ro"tatic ma"" may &e attri&uted to the
nonglandular anterior <bromuscular stroma( Thi" region
normally e)tend" from the &ladder nec# to the "triated "$hincter,
although con"idera&le $ortion" of it may &e re$laced &y glandular
ti""ue in adenomatou" enlargement of the $ro"tate. It i" directly
continuou" with the $ro"tatic ca$"ule, anterior %i"ceral fa"cia, and
anterior $ortion of the $re$ro"tatic "$hincter and i" com$o"ed of
ela"tin, collagen, and "mooth and "triated mu"cle. It i" rarely
in%aded &y carcinoma.
Clinically) the "rostate is often s"o%en of as havin*
t'o lateral lobes) se"arated by a central sulcus that is
"al"able on rectal e$amination) and a middle lobe)
'hich may "ro2ect into the bladder in older men( The"e
lo&e" do not corre"$ond to hi"tologically de'ned "tructure" in the
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normal $ro"tate &ut are u"ually related to $athologic enlargement
of the tran"ition 2one laterally and the $eriurethral gland"
centrally.
< SCTION I = Anatomy
*igure -5?. onal anatomy of the $ro"tate a" de"cri&ed &y !.H. Mc(eal +(ormal
hi"tology of the $ro"tate. Am ! urg athol 71?7-55/.
The tran"ition 2one "urround" the urethra $ro)imal to the ejaculatory duct". The
central 2one "urround" the ejaculatory duct" and $roject"
under the &ladder &a"e. The $eri$heral 2one con"titute" the &ul# of the a$ical,
$o"terior, and lateral a"$ect" of the $ro"tate. The anterior
'&romu"cular "troma e)tend" from the &ladder nec# to the "triated urethral
"$hincter. + 779, Baylor College of Medicine./
*igure -58. 6etrograde urethrogram of the male urethra
demon"trating urethral anatomy. , $ro"tatic urethra1
, %erumontanum, into which enter the ejaculatory duct"1
5, mem&ranou" urethra, note $hy"iologic narrowing of urethral
luminal diameter due to e)ternal "triated "$hincter1 ;, &ul&ar
urethra1 <, $endulou" urethra.
>
=
4
9
*igure -5. A)ial T0weighted magnetic re"onance image of the
male $el%i" through the $ro"tate gland and adjacent "tructure".
, urinary &ladder1 , lateral lo&e" of $ro"tate1 5, %erumontanum1
;, "triated urethral "$hincter1 <, inferior $u&ic ramu"1 ?, cor$u"
"$ongio"um in cro"" "ection1 8, e)ternal iliac artery.
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4 4
=
>
E
Vascular Su""ly
Mo"t commonly, the arterial su""ly to the "rostate arises
from the inferior vesical artery( A" it a$$roache" the gland,
the artery +often "e%eral/ di%ide" into two main &ranche" +*ig.
-;9/. The urethral arterie" $enetrate the $ro"tato%e"ical junction
$o"terolaterally and tra%el inward, $er$endicular to the urethra.
They a$$roach the &ladder nec# in the 0 to <0ocloc# and 80 to
0ocloc# $o"ition", with the large"t &ranche" located $o"teriorly.
They then turn caudally, $arallel to the urethra, to "u$$ly it, the
$eriurethral gland", and the tran"ition 2one. Thu" in &enign $ro"tatic
hy$ertro$hy, the"e arterie" $ro%ide the $rinci$al &lood "u$$ly
of the adenoma +*loc#", 758/. 3hen the"e gland" are re"ected or
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia <7
enucleated, the mo"t "igni'cant &leeding i" commonly encountered
at the &ladder nec#, $articularly at the ;0 and 0ocloc#
$o"ition".
The ca"sular artery is the second main branch of the
"rostatic artery( Thi" artery gi%e" o4 a few "mall &ranche" that
$a"" anteriorly to ramify on the $ro"tatic ca$"ule. The &ul# of thi"
artery run" $o"terolateral to the $ro"tate with the ca%ernou"
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ner%e" +neuro%a"cular &undle"/ and end" at the $el%ic dia$hragm.
The ca$"ular &ranche" $ierce the $ro"tate at right angle" and
follow the reticular &and" of "troma to "u$$ly the glandular
ti""ue". Fenou" drainage of the $ro"tate i" a&undant through the
$eri$ro"tatic $le)u" +"ee *ig. -9/.
!ym"hatic draina*e is "rimarily to the obturator and
internal iliac nodes +"ee *ig. -/. A "mall $ortion of drainage
may initially $a"" through the $re"acral grou$ or, le"" commonly,
the e)ternal iliac node".
Nerve Su""ly
Sym"athetic and "arasym"athetic innervation from the
"elvic "le$us travels to the "rostate throu*h the cavernous
nerves( (er%e" follow &ranche" of the ca$"ular artery to
ramify in the glandular and "tromal element". ara"ym$athetic
ner%e" end at the acini and $romote "ecretion1 "ym$athetic '&er"
cau"e contraction of the "mooth mu"cle of the ca$"ule and "troma.
*igure -57. Tran"rectal ultra"ound of the $ro"tate
demon"trating the , $eri$heral 2one and , tran"ition 2one.
4
9
*igure -;9. Arterial "u$$ly of the $ro"tate. +Ada$ted from
*loc#" 6@. The arterial di"tri&ution within the $ro"tate gland
it" role in tran"urethral $ro"tatic re"ection. ! Urol 758158<8./
Inferior
%e"ical a.
Minor %e""el" -
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&ranche" from
middle hemorrhoidal
and $udendal
Ca$"ular grou$
of arterie"
Urethral grou$
of arterie"
ro"tatic a.
R0Adrenergic &loc#ade dimini"he" $ro"tate "tromal and $re$ro"tatic
"$hincter tone and im$ro%e" urinary :ow rate" in men
a4ected with &enign $ro"tatic hy$ertro$hy1 thi" em$ha"i2e" that
thi" di"ea"e a4ect" &oth the "troma and the e$ithelium. e$tidergic
and nitric o)ide "yntha"e-containing neuron" al"o ha%e &een
found in the $ro"tate and may a4ect "mooth mu"cle rela)ation
+Burnett, 77</. A4erent neuron" from the $ro"tate tra%el through
the $el%ic $le)u"e" to $el%ic and thoracolum&ar "$inal center". A
$ro"tatic &loc# may &e achie%ed &y in"tilling local ane"thetic into
the $el%ic $le)u"e".
-embranous 7rethra
In it" cour"e from the a$e) of the $ro"tate to the $erineal mem&rane,
the membranous urethra s"ans on avera*e 4 to
4(> cm +range . to < cm/ +Myer", 77/ +"ee *ig -58/. It i" "urrounded
&y the "triated +e)ternal/ urethral "$hincter, which i"
often incorrectly de$icted a" a :at "heet of mu"cle "andwiched
&etween two layer" of fa"cia. The "triated "$hincter i" actually
"ignet ring "ha$ed, &road at it" &a"e, and narrowing a" it $a""e"
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through the urogenital hiatu" of the le%ator ani to meet the a$e)
of the $ro"tate +"ee *ig. -;1 "ee al"o *ig". -9, -8, and -5/.
In utero, thi" mu"cle form" a %ertically oriented tu&e that e)tend"
from the $erineal mem&rane to the &ladder nec# +elrich, 79/.
A" the $ro"tate grow", $o"terior and lateral $ortion" of thi" mu"cle
atro$hy, although tran"%er"e '&er" $er"i"t on the entire anterior
$ro"tate through adulthood. At the a$e) of the $ro"tate, circular
'&er" "urround the urethra and thin $o"teriorly to in"ert into a
'&rou" ra$he. Di"tally, the '&er" do not meet $o"teriorly1 rather,
they ac>uire an "ha$e a" they fan out laterally o%er the $erineal
mem&rane. Throughout it" length, the $o"terior $ortion of the
"triated "$hincter in"ert" into the $erineal &ody. 3hen the "$hincter
contract", the wall" of the urethra are $ulled $o"teriorly toward
the $erineal &ody +tra""er et al, 77/. In contra"t to the le%ator
ani, the "$hincter con"i"t" only of 'ne, ty$e I +"low0twitch/ '&er",
rich in acid0"ta&le myo"in ATa"e, which a$$ear de"igned for tonic
contraction. The myo'&ril" are "urrounded &y a&undant connecti%e
ti""ue that &lend" with adjacent "u$$orting "tructure".
The "triated "$hincter i" related anteriorly to the dor"al %ein
com$le) +which may in%ade it" anterior $ortion with age/ and
laterally to the le%ator ani. Connective tissue from dee"
'ithin the lateral and anterior 'alls inserts into the
"ubo"rostatic li*aments "osteriorly and into the sus"ensory
li*ament of the "enis anteriorly to form a slin* of
<brous tissue that sus"ends the urethra from the "ubis
?9 SCTION I = Anatomy
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+*ig. -;/. It run" $o"terior to the %e""el" of the cord and through
the inguinal canal and emerge" in the $el%i" lateral to the inferior
e$iga"tric %e""el" +"ee *ig. -5/. At the internal ring, it di%erge"
from the te"ticular %e""el" and $a""e" medial to all "tructure" of
the $el%ic "ide wall to reach the &a"e of the $ro"tate $o"teriorly
+"ee *ig". -5, -5, and -?/. The terminal %a" i" dilated and
tortuou" +am$ulla/ and i" ca$a&le of "toring "$ermato2oa. The %a"
ha" a thic# wall of outer longitudinal and inner circular "mooth
mu"cle and i" lined &y $"eudo"trati'ed columnar e$ithelium with
nonmotile "tereocilia.
The seminal vesicle is a lateral out"ouchin* of the vas)
a$$ro)imately < cm long, with a ca$acity of 5 to ; mL +"ee *ig".
-, -5?, and -;5/. De"$ite it" name, it doe" not "tore "$erm
&ut contri&ute" the large"t $ortion of :uid to the ejaculate. The
"eminal %e"icle com$ri"e" a "ingle coiled tu&e with "e%eral out$ouching"
that i" lined &y columnar e$ithelium with go&let cell".
The tu&e i" enca"ed in a thin layer of "mooth mu"cle and i" held
in it" coiled con'guration &y a loo"e ad%entitia.
The "eminal %e"icle and am$ulla of the %a" lie $o"terior to the
&ladder. The ureter enter" the &ladder medial to the ti$ of the
"eminal %e"icle. A" the "eminal %e"icle and %a" join to form
the ejaculatory duct, their "mooth mu"cle coat" fu"e with the
$ro"tatic ca$"ule at it" &a"e. ,enonvilliers fascia or) occasionally)
the rectovesical "ouch of "eritoneum se"arates
these structures from the rectum +"ee *ig. -8/. Unle""
in%ol%ed &y a $athologic $roce"", the"e "tructure" are not $al$a&le
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on rectal e)amination.
The blood su""ly for the seminal vesicles and vasa
comes from the vesiculodeferential artery) a &ranch of the
"u$erior %e"ical artery. Thi" artery "u$$lie" the %a" throughout it"
length and then $a""e" onto the anterior "urface of the "eminal
%e"icle near it" ti$. During radical $ro"tatectomy the artery i"
in%aria&ly found &etween the %a" and "eminal %e"icle and mu"t
&e i"olated and controlled. Additional arterial "u$$ly may come
from the inferior %e"ical artery. The $el%ic %a" and "eminal %e"icle
drain into the $el%ic %enou" $le)u". Lym$hatic drainage $a""e" to
the e)ternal and internal iliac node" +"ee *ig. -/. Inner%ation
+teiner, 77;/. A "imilar "u"$en"ory mechani"m i" found in the
female urethra +"ee later di"cu""ion and *ig. -;/. Two &ul&ourethral
gland" lie "u$erior to the $erineal mem&rane and are in%e"ted
in the &road &a"e of "$hincter mu"cle. During "e)ual e)citement,
the"e gland" "ecrete clear mucu" into the &ul&ou" urethra.
The striated s"hincter corres"onds to the location of
"ea% urethral closin* "ressure and i" re"$on"i&le for continence
after $ro"tatectomy. Com$onent" in%ol%ed in generating
thi" clo"ing $re""ure are +/ the $"eudo"trati'ed columnar e$ithelium,
which contract" into radial fold" a" it meet" to occlude the
lumen1 +/ the "u&muco"a, which i" rich with &lood %e""el" and "oft
connecti%e ti""ue and contri&ute" to urethral "ealing +6a2 et al,
78/1 +5/ the longitudinal and circular urethral "mooth mu"cle
+intrin"ic com$onent of the e)ternal "$hincter/1 +;/ the "triated
"$hincter1 and +</ the $u&ourethral com$onent of the le%ator ani.
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Gro"" di""ection and retrograde a)onal tracing techni>ue" ha%e
con'rmed that the "triated "$hincter i" "u$$lied &y the $udendal
ner%e +Tanagho et al, 7/. @owe%er, urologi"t" ha%e long &een
$u22led a" to why $udendal ner%e "ectioning doe" not a&late
"$hincter acti%ity. Law"on +78;/ and %ara and colleague" +77;/
identi'ed a second source of somatic innervation to the
s"hincter8 a branch of the sacral "le$us that runs on the
"elvic surface of the levator ani +"ee *ig. -5/. Injury to thi"
ner%e at radical $ro"tatectomy may contri&ute to $o"to$erati%e
urinary incontinence +@olla&augh et al, 778/. Autonomic inner%ation
to the intrin"ic "mooth mu"cle of the mem&ranou" urethra
i" li#ely gi%en &y the ca%ernou" ner%e" a" they $a"" near&y,
although di%iding the"e ner%e" doe" not a$$ear to a4ect urinary
continence "igni'cantly +teiner et al, 77/. A4erent '&er" from
the "triated "$hincter ha%e not &een de'ned &ut are "ure to ha%e
intere"ting and im$ortant functional role" &ecau"e thi" mu"cle
lac#" $ro$rioce$ti%e mu"cle "$indle" +Go"ling et al, 7/.
Vas ,eferens and Seminal Vesicle
As it arises from the tail of the e"ididymis) the vas
#ductus& deferens is some'hat tortuous for 4 to cm
*igure -;. Urethral "u"$en"ory mechani"m. The $u&ourethral ligament +.U.L./ i"
com$o"ed of an anterior $ortion +"u"$en"ory ligament
of the clitori"/, a $o"terior $ortion +$u&ourethral ligament of endo$el%ic fa"cia/, andan intermediate $ortion that &ridge" the other two.
+*rom Milley , (ichol" D@. The relation"hi$ &etween the $u&o0urethral ligament"
and the urogenital dia$hragm in the human female.
Anat 6ec 781895./
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C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ?
*igure -;. Te"ti" and e$ididymi". A) ne to three "eminiferou" tu&ule" 'll each
com$artment and drain into the rete te"ti" in the
media"tinum. Twel%e to 9 e4erent ductule" &ecome con%oluted in the head of the
e$ididymi" and drain into a "ingle coiled duct of the
e$ididymi". The %a" i" con%oluted in it" 'r"t $ortion. B) Cro"" "ection of the te"ti",
"howing the media"tinum and "e$tation" continuou"
with the tunica al&uginea. The $arietal and %i"ceral tunica %aginali" are con:uent
where the %e""el" and ner%e" enter the $o"terior a"$ect of
the te"ti".
$ermatic
cord
Fa"
Fa" deferen"
deferen"
Body
Tail
eminiferou"
tu&ule
@ead of
e$ididymi"
H$ididymi"
Tunica
al&uginea
Tunica
%aginali"
A B
Media"tinum
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te"ti"
ari"e" from the $el%ic $le)u", with major e)citatory e4erent" contri&uted
&y the +"ym$athetic/ hy$oga"tric ner%e" +ol&ec# and
teer", 775/.
.emale Pelvic Viscera
The uterus mea"ure" V ? V ; cm in a normal woman and i"
com$o"ed largely of den"e "mooth mu"cle +"ee *ig". -7 and
-;;/. It ha" a narrowed nec#, the cer%i), which o$en" through
the anterior %aginal wall and a &road cor$u" that i" ca$$ed &y the
rounded fundu". A" di"cu""ed earlier, it lie" in front of the rectum
and o%er the dome of &ladder1 it" im$re""ion can &e o&"er%ed
cy"to"co$ically +"ee *ig". - and -5/. The fallo$ian tu&e"
e)tend laterally from the junction of the cor$u" and fundu" and
are dra$ed &y lea%e" of $eritoneum called the broad ligaments +"ee
*ig". -5 and -7/. A" they e)tend to the $el%ic "ide wall", the
fallo$ian tu&e" angle u$ and &ac#ward to o$en $o"teromedially.
*igure -;5. A)ial T0weighted magnetic re"onance image of the
male $el%i" illu"trating the , &ladder and , "eminal %e"icle".
The tu&e" are di%ided into four "egment"Wuterine, i"thmu",
am$ulla, and infundi&ulumWand are crowned &y the 'm&riae.
The o%ary re"t" $o"terior to the el&ow of the tu&e and i" "u$$orted
&y it" own $eritoneal fold, the me"o%arium. The ureter may &e
found directly $o"terior to the o%ary, co%ered &y $el%ic $eritoneum.
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The infundi&ulo$el%ic ligament, mentioned earlier,
*igure -;;. ey anatomic relation"hi$" in the female $el%i"
illu"trated on "agittal midline T0weighted magnetic re"onance
image. , urinary &ladder1 , $u&ic "ym$hy"i"1 5, urethra1 ;,
%aginaWnote that the %agina i" retro:e)ed $o"teriorly o%er the
le%ator $late. The le%ator $late $ro%ide" critical female $el%ic
"u$$ort1 <, cer%i)1 ?, uteru".
?
>
=
4
? SCTION I = Anatomy
"ide of the urethra +#ene gland"/ and em$ty through two "mall
duct" to either "ide of the e)ternal urethral meatu". A thic#, richly
%a"cular "u&muco"a "u$$ort" the urethral e$ithelium and gland"
+"ee *ig. -5/. Together, the muco"a and "u&muco"a form a
cu"hion that contri&ute" "igni'cantly to urethral clo"ure $re""ure
+6a2 et al, 78/. The"e layer" are e"trogen de$endent1 at meno$au"e
they may atro$hy, re"ulting in "tre"" incontinence. A relati%ely
thic# layer of inner longitudinal "mooth mu"cle continue"
from the &ladder to the e)ternal meatu" to in"ert into $eriurethral
fatty and '&rou" ti""ue. In contra"t to the male $ro)imal urethra,
no circular "mooth mu"cle "$hincter can &e identi'ed. A rather
thin layer of circular "mooth mu"cle en%elo$" the longitudinal
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'&er" throughout the length of the urethra. It i" thought that the
longitudinal "mooth mu"cle of the urethra contract" coordinately
with the detru"or during micturition to "horten and widen the
urethra +Go"ling, 787/.
The striated urethral s"hincter invests the distal t'o
thirds of the female urethra +elrich, 75/. It i" com$o"ed
e)clu"i%ely of delicate ty$e I +"low0twitch/ '&er" "urrounded &y
a&undant collagen. ro)imally, it form" a com$lete ring around
the urethra that corre"$ond" to the 2one of highe"t urethral
clo"ure $re""ure +"ee *ig. -5/. *arther down the urethra, the
'&er" do not meet $o"teriorly &ut continue o4 the lateral "ide" of
the urethra onto the anterior and lateral wall of the %agina. Contraction
of the"e '&er" +the com$re""or urethrae/ clo"e" the urethra
again"t the ')ed anterior %aginal wall. (ear the %e"ti&ule, the
'&er" com$letely "urround the urethra and %agina to form a urethro%aginal
"$hincter. Contraction of thi" mu"cle grou$, along
with &ul&o"$ongio"u", tighten" the urogenital hiatu".
The sus"ensory li*ament of the clitoris #anterior urethral
li*ament& and the "ubourethral li*aments #"osterior
urethral li*aments& form a slin* that sus"ends the
urethra beneath the "ubis +"ee *ig". - and -;/ +acharin,
7?5/. The "triated urethral "$hincter recei%e" dual "omatic inner%ation,
li#e that in the male, from the $udendal and $el%ic "omatic
ner%e" +Borira#chanya%at et al, 778/. Little "ym$athetic inner%ation
i" found in the female urethra. ara"ym$athetic cholinergic
'&er" are found throughout the "mooth mu"cle. omatic and
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autonomic ner%e" to the urethra tra%el on the lateral wall" of the
%agina near the urethra. During tran"%aginal incontinence "urgery,
the anterior %aginal wall "hould &e inci"ed laterally to a%oid the"e
ner%e" and $re%ent ty$e III urinary incontinence +Ball et al, 778/.
.emale Pelvic Su""ort
The $el%ic mu"cle" and fa"ciae coo$erate to $re%ent $rola$"e of
the urogenital organ" through the hiatu". Three functional
su""ortive elements are reco*ni/ed8 #9& the "ubovisceral
and "erineal muscles) 'hich form a s"hincter around
the uro*enital hiatus +"ee *ig. -5/1 #4& the levator "late)
which act" a" a hori2ontal "helf &eneath the &ladder, uterine
cer%i), $o"terior %agina, and rectum +"ee *ig. -/1 and #& the
cardinal and uterosacral li*aments) which anchor the $el%ic
%i"cera o%er the le%ator $late +acharin, 7<1 Mo"twin, 771
DeLancey, 775/. The $el%ic mu"cle" contract tonically to counteract
gra%itational force". In re"$on"e to "tre"", the le%ator ani
contract", clo"ing the urogenital hiatu" and increa"ing the antero$o"terior
length of the le%ator $late. Increa"ed intra0a&dominal
$re""ure force" the $el%ic %i"cera downward again"t a ')ed le%ator
$late, clo"ing the %agina li#e a :a$ %al%e.
Pelvic and "erineal muscles "lay the *reatest role in
"elvic su""ort( Damage to the $erineal &ody during $arturition
de"troy" the urogenital "$hincter, enlarge" the urogenital hiatu",
"u"$end" the o%ary and lateral fallo$ian tu&e from the $el%ic "ide
wall and tran"mit" the o%arian %e""el" to &oth "tructure". The
round ligament of the o%ary $a""e" medially through the &road
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ligament to ') the o%ary to the lateral wall of the uteru". Beneath
it" $oint of attachment, the round ligament of the uteru" $a""e"
laterally, in the lea%e" of the &road ligament, to e)it through to
the inguinal canal and attach to the la&ial fat $ad +"ee *ig". -5
and -7/.
The uterine artery crosses in front of the ureter and
runs in the broad and cardinal li*aments to su""ly the
"ro$imal va*ina) uterus) and medial t'o thirds of the
fallo"ian tube +"ee *ig. -7/. It i" joined &y a rich $le)u" of
uterine %ein" that freely connect with the o%arian %ein". (er%e"
from the $el%ic $le)u" tra%el to the female $el%ic %i"cera through
the cardinal and utero"acral ligament" in the com$any of the
%e""el"1 therefore hy"terectomy can cau"e a :accid neurogenic
&ladder.
The va*ina e$tends in'ard from the vestibule at
a =>?de*ree an*le and then turns hori/ontal over
the levator "late +"ee *ig". - and -;;/. It i" lined &y rugated
non#eratini2ed ">uamou" e$ithelium &ac#ed &y a thic#, well%a"culari2ed
lamina $ro$ria. It i" "urrounded &y a "mooth mu"cle
coat of inner circular and "tronger e)ternal longitudinal layer". In
cro"" "ection, the %agina i" @ "ha$ed +"ee *ig. -;/ a" a re"ult of
'rm attachment" of it" anterior wall to the le%ator ani at the arcu"
tendineu" fa"cia $el%i", and of it" $o"terior wall to the recto%aginal
"e$tum. The anterior %aginal wall i" $ierced &y the cer%i) $ro)imally.
The "hallow fo""ae around the cer%i) are referred to a" the
anterior, lateral, and $o"terior fornice". Becau"e the a$e) of the
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%agina i" co%ered with the $eritoneum of the rectouterine $ouch,
the $eritoneal ca%ity may &e acce""ed through the $o"terior forni)
+"ee *ig. -/.
Immediately in front of the cervi$) the base of the
bladder rests on the va*inal 'all( mooth mu"cle '&er"
tether the $o"terior &ladder wall and &a"e to the uterine cer%i)
and %agina +"ee *ig". - and -;;/. Di%i"ion of the"e '&er" yield"
$o"terior acce"" to the %e"ico%aginal "$ace. Thi" "$ace e)tend"
di"tally to the $ro)imal third of the urethra +where the urethra
and %agina fu"e/ and i" limited to each "ide &y the lateral ligament"
of the &ladder. It may &e acce""ed tran"%aginally through inci"ion
of the anterior %aginal wall in front of the cer%i). Inci"ion of the
anterior %aginal wall to either "ide of the urethra lead" into the
retro$u&ic "$ace +"ee *ig. -/. The tough lea%e" of the %i"ceral
endo$el%ic fa"cia are felt medially and "hould &e included in all
tran"%aginal urethral "u"$en"ion $rocedure" +Mo"twin, 77/.
The va*ina is se"arated from the rectum by the rectova*inal
se"tum +"ee *ig. -/, and rectocele" re"ult from a lo""
of integrity of thi" "e$tum. Dee$ to thi" "e$tum lie" a "econd
$otential "$ace, the recto%aginal "$ace. The &owel may herniate
into thi" "$ace to form an enterocele. n it" lateral "urface", the
%agina i" related to the le%ator ani. (ear the %e"ti&ule, '&er" of
the le%ator ani &lend and fu"e with the %aginal mu"culari". The
%aginal %e""el" and ner%e" lie on the anterolateral "urface of the
%agina dee$ to the arcu" tendineu" fa"cia $el%i".
.emale 7rethra
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On avera*e) the female urethra traverses = cm from the
bladder nec% to the va*inal vestibule +"ee *ig. -;;/. Its
linin* chan*es *radually from transitional to non%eratini/ed
strati<ed s5uamous e"ithelium( -any small
mucous *lands o"en into the urethra and can gi%e ri"e to
urethral di%erticula. Di"tally, the"e gland" grou$ together on either
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ?5
rectourethrali" and &lend" with the e)ternal "$hincter, although
a few '&er" in"ert in the "#in around the anu" +corrugator cuti"
ani/ to gi%e it a $uc#ered a$$earance. The e$ternal s"hincter
surrounds the internal s"hincter and is divided into subcutaneous)
su"er<cial) and dee" "ortions( The "u&cutaneou"
$art attache" to the $erineal &ody &y collagenou" and mu"cular
'&er" that are thic#e"t "u$er'cially and referred to a" the central
tendon of the perineum. The "u$er'cial "$hincter attache" to the
$erineal &ody and coccy). At the $o"terior in:ection of the
rectum, the dee$ "$hincter &lend" with the $u&orectali" "ling of
le%ator ani. At thi" le%el, a 'rm &and may &e felt on rectal e)amination
and corre"$ond" to the internal and e)ternal "$hincter.
Di%i"ion of thi" mu"cular &and re"ult" in fecal incontinence. The
$ro"tate may &e acce""ed anterior to the "$hincter, &y di%iding the
central tendon and "$hincteric attachment" to the $erineum
+Eoung $rocedure/ or &y following the anterior rectal wall &eneath
the e)ternal anal "$hincter +Belt $rocedure/.
-ale 7ro*enital Trian*le
The entire uro*enital trian*le is brid*ed by the uro*enital
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dia"hra*m( The "crotum hang" from the anterior a"$ect of
the urogenital triangle1 in the $o"terior a"$ect, "#in and "u&cutaneou"
fat o%erlie Colle" fa"cia. The $erineal mem&rane and the
$o"terior and lateral attachment" of Colle" fa"cia limit a $otential
"$ace #nown a" the supercial pouch +"ee *ig". -;, -<, and -7/.
In thi" "$ace, the three erectile &odie" of the $eni" ha%e their &ony
and fa"cial attachment" +the root of the $eni"/. The $aired cor$ora
ca%erno"a attach to the inferior i"chio$u&ic rami and $erineal
mem&rane and are "urrounded &y the i"chioca%erno"u" mu"cle".
The cor$u" "$ongio"um dilate" a" the &ul& of the $eni" and i" ')ed
to the center of the $erineal mem&rane. It i" encom$a""ed &y the
&ul&o"$ongio"u" mu"cle" +"ee *ig. -;?/ that ari"e from the $erineal
&ody and from a central tendinou" ra$he and $a"" around
and erode" the le%ator $late. Aging and &irth trauma $artially
dener%ate and wea#en the le%ator ani +noo#" et al, 7</. 3ith
lo"" of mu"cular "u$$ort, intra0a&dominal force" im$inge directly
on the $el%ic fa"ciae1 o%er time, the"e either tear or "tretch. rocedure"
to correct $el%ic $rola$"e or urinary incontinence that rely
"olely on the"e fa"ciae may &e "ucce""ful initially &ut do not fare
well o%er time +Troc#man et al, 77</. 6e$air of a "ingle $el%ic
defectWa cy"tocele for in"tanceWmay unma"# another +enterocele,
rectocele/1 therefore "ucce""ful re$air of $el%ic $rola$"e mu"t
addre"" all com$onent" of anatomic "u$$ort +acharin, 7<1
DeLancey, 775/.
P+IN7-
The "erineum lies amon* the "ubis) thi*hs) and buttoc%s
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and is limited su"eriorly by the levator ani( Fiewed from
&elow, the "ym$hy"i" $u&i", i"chial tu&ero"itie", and coccy)
outline the diamond "ha$e of the $erineum1 the inferior i"chio$u&ic
rami and "acrotu&erou" ligament" form it" &ony and ligamentou"
wall" +*ig. -;<1 "ee al"o *ig". -7 and -;?/. A line
drawn through the i"chial tu&ero"itie" di%ide" the $erineum into
an anal and a urogenital triangle.
Anal Trian*le
At the a"e$ of the "rostate) the rectum turns a""ro$imately
F@ de*rees "osteriorly and inferiorly to become
the anus +"ee *ig". -9 and -;/. It tra%er"e" ; cm to reach the
"#in near the center of the anal triangle. The "u&cutaneou" fat that
"urround" the anu" i" continuou" with that of the urogenital triangle,
&uttoc#", and medial thigh. Laterally, the fat 'll" the i"chiorectal
fo""a, a "$ace &ounded &y the le%ator ani medially, and
o&turator internu", and the "acrotu&erou" ligament laterally +"ee
*ig. -</. Anteriorly, thi" "$ace e)tend" into a rece"" a&o%e the
urogenital dia$hragm1 $o"teriorly, it i" continuou" with the intermediate
"tratum of the $el%i" through the "ciatic foramina.
Through thi" continuity, infection" may tra%el &etween the
$erineum and the $el%ic ca%ity.
The anal "$hincter i" di%ided into internal and e)ternal com$onent".
The internal s"hincter re"resents a thic%enin*
of the inner circular smooth muscle layer of the rectum(
The outer longitudinal "mooth mu"cle thin" &eyond the
*igure -;<. Male $erineum. +*rom An"on B!, McFay CB.
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urgical anatomy. ?th ed. hiladel$hia 3B aunder"1 7;. $. 75./
Posterior) or
anal "erineum
Anterior) or
uro*enital
"erineum
)
)
)
)
*igure -;?. A)ial T0weighted magnetic re"onance image of
male $el%i". , cor$ora ca%erno"a in cro"" "ection1 , cor$u"
"$ongio"um in cro"" "ection1 5, cor$u" "$ongio"um in $erineum1
;, &ul&o"$ongio"u" mu"cle, which a""i"t" urine or "eminal :uid
e)$ul"ion from &ul&ar urethra1 <, crura of cor$ora ca%erno"aW
note di%ergence of crura a" they in"ert on $u&ic &one1 ?, i"chial
tu&ero"itie"1 8, rectum.
9 9
4
> >
=
E E
?; SCTION I = Anatomy
dor"al ner%e of the $eni", tra%el" %entral to the main $udendal
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trun# in Alcoc# canal. e%eral inferior rectal &ranche" "u$$ly the
e)ternal "$hincter mu"cle and $ro%ide "en"ation to $erianal "#in.
The $erineal &ranche" follow the $erineal artery into the "u$er'cial
$ouch to "u$$ly the i"chioca%erno"u", &ul&o"$ongio"u", and
tran"%er"u" $erinei mu"cle". A few of the"e &ranche" continue
anteriorly to "u$$ly "en"ation to the $o"terior "crotum. Additional
$erineal &ranche" $a"" dee$ to the $erineal mem&rane to "u$$ly
the le%ator ani and "triated urethral "$hincter.
Penis
A" di"cu""ed, the root of the $eni" i" ')ed to the $erineum within
the "u$er'cial $ouch. The cor"ora cavernosa 2oin beneath
the "ubis #"enile hilum& to form the ma2or "ortion of
the body of the "enis( They are "e$arated &y a "e$tum that
&ecome" $ectiniform di"tally, "o their %a"cular "$ace" freely communicate.
They are enclo"ed &y the tough tunica al&uginea, which
i" $redominantly collagenou" +*ig. -;/. It" outer longitudinal
and inner circular '&er" form an undulating me"hwor# when the
$eni" i" :accid and a$$ear tightly "tretched with erection +Gold"tein
et al, 7/. mooth mu"cle &undle" tra%er"e the erectile
&odie" to form the endothelium0lined ca%ernou" "inu"e". The"e
"inu"e" gi%e the erectile ti""ue a "$ongy a$$earance on gro""
e)amination.
Di"tal to the &ul&, the cor$u" "$ongio"um ta$er" and run" on
the under"ide +%entrum/ of the cor$ora ca%erno"a +"ee *ig. -;?/
and then e)$and" to ca$ them a" the glan" $eni". The corona
"e$arate" the &a"e of the glan" from the "haft of the $eni". The
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the &ul& to attach to the $erineal mem&rane and dor"um of the
$eni". Contraction of the i"chioca%erno"u" and &ul&o"$ongio"u"
mu"cle" com$re""e" the erectile &odie" and $otentiate" $enile erection.
The tran"%er"u" $erinei mu"cle" +"u$er'cial and dee$/ run
along the $o"terior edge of the $erineal mem&rane and are thought
to "ta&ili2e the $erineal &ody. Dee$ to the $erineal mem&rane re"t"
the "triated urethral "$hincter +di"cu""ed earlier/.
Blood su""ly to the anal and uro*enital trian*les is
derived lar*ely from the internal "udendal vessels +*ig.
-;8/. After entering the $erineum through the le""er "ciatic
foramen, the artery run" in a fa"cial "heath on the medial a"$ect
of o&turator internu", the $udendal canal +of Alcoc#/. Harly in it"
cour"e, it gi%e" o4 three or four inferior rectal &ranche" to the
anu". It" $erineal &ranch $ierce" Colle" fa"cia to "u$$ly the mu"cle"
of the "u$er'cial $ouch and continue" anteriorly to "u$$ly the
&ac# of the "crotum. The internal $udendal terminate" a" the
common $enile artery +to &e di"cu""ed/.
The internal "udendal veins communicate freely 'ith
the dorsal vein com"le$ by "iercin* the levator ani( The"e
communicating %e""el" enter the $el%ic %enou" $le)u" on the
lateral "urface of the $ro"tate and are a common, often une)$ected,
"ource of &leeding during a$ical di""ection of the $ro"tate.
The inferior rectal %ein" ana"tomo"e with the middle and "u$erior
rectal %ein" and $roduce an im$ortant connection &etween the
$ortal and "y"temic circulation. &"truction of the $ortal or "y"temic
%enou" "y"tem may cau"e "hunting of collateral %enou"
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drainage through the $ortal "y"tem, manife"ted &y hemorrhoid".
The "udendal nerve follo's the vessels in their course
throu*h the "erineum +"ee *ig. -;8/. It" 'r"t &ranch, the
*igure -;8. Male $erineum, illu"trating the internal
$udendal artery and it" &ranche" on the left and the
$udendal ner%e and it" &ranche" on the right.
erineal a. erineal n.
Dor"al n.
of $eni"
Inf. rectal n.
Artery of $eni"
Inf. rectal a.
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ?<
*igure -;. Cro"" "ection of the $eni", demon"trating the relation"hi$ &etween the
cor$oral &odie", $enile fa"cia, %e""el", and ner%e".
+*rom De%ine !r C!, Angermeier 3. Anatomy of the $eni" and mate $erineum. AUA
U$date erie" 77;159-5./
u$er'cial and dee$ dor"al %ein
Dor"al artery
*a"cicle" of dor"al ner%e
#in
u$er'cial
+darto"/ fa"cia
Dee$ +Buc#/
fa"cia
u&tunical "$ace
Ca%erno"al artery
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Hrectile ti""ue
Tunica al&uginea
uter longitudinal layer
Inner circular layer
Cor$u" "$ongio"um
"$ongio"um i" tra%er"ed throughout it" length &y the anterior
urethra, which &egin" at the $erineal mem&rane +"ee *ig". -5<
and -58/. The anterior urethra i" dilated in it" &ul&ar and glanular
"egment" +fo""a na%iculari"/ and narrowe"t at the e)ternal meatu".
ro)imally, it i" lined &y "trati'ed and $"eudo"trati'ed columnar
e$ithelium, di"tally &y "trati'ed ">uamou" e$ithelium. The mucu""ecreting
gland" +of Littre/ may &e "een a" "mall out$ouching" of
the muco"a.
Buc% fascia surrounds both cavernosal bodies dorsally
and s"lits to surround the s"on*iosum ventrally +"ee *ig.
-;/. Hla"tic and collagenou" '&er" from the rectu" "heath &lend
with and "urround Buc# fa"cia a" the fundiform ligament of the
$eni". Dee$er '&er" from the $u&i" form the "u"$en"ory ligament
of the $eni". In the $erineum, Buc# fa"cia fu"e" with the tunica
al&uginea dee$ to the mu"cle" of the erectile &odie" +Uhlenhuth
et al, 7;7/. Di"tally, it fu"e" with the &a"e of the glan" at the
corona. Bleeding from a tear in the cor$oral &odie" +e.g., $enile
fracture/ i" u"ually contained within Buc# fa"cia, and ecchymo"i"
i" limited to the $enile "haft.
The s%in of the "enile shaft is hi*hly elastic and
'ithout a""enda*es +hair or glandular element"/, e)ce$t for
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the "megma0$roducing gland" at the &a"e of the corona. It i"
de%oid of fat and >uite mo&ile &ecau"e of the loo"e attachment of
it" darto" &ac#ing to Buc# fa"cia. Di"tally, it fold" o%er the glan"
a" the fore"#in and attache" 'rmly &elow the corona. It" &lood
"u$$ly i" inde$endent of the erectile &odie" and i" deri%ed from
the e)ternal $udendal &ranche" of the femoral %e""el" +"ee *ig.
-</. The"e %e""el" enter the &a"e of the $eni" to run longitudinally
in the darto" fa"cia a" a richly ana"tomotic networ#. Thu" $enile
"#in may &e mo&ili2ed on a %a"cular $edicle a" the ideal ti""ue for
urethral recon"truction. The "#in of the glan" i" immo&ile a" a
re"ult of it" direct attachment to the underlying, thin tunica
al&uginea.
The common "enile artery continues in Alcoc% canal)
above the "erineal membrane) and terminates in three
branches to su""ly the erectile bodies +*ig. -;7/. The &ul&ourethral
artery $enetrate" the $erineal mem&rane to enter the
"$ongio"um from a&o%e at it" $o"terolateral &order. Thi" large,
"hort artery can &e diOcult to i"olate and control during urethrectomy.
It "u$$lie" the urethra, "$ongio"um, and glan". The ca%erno"al
artery $ierce" the cor$oral &ody in the $enile hilum to near
the center of it" erectile ti""ue. It gi%e" o4 "traight and helicine
arterie" that ramify to "u$$ly the ca%ernou" "inu"e". The dor"al
artery of the $eni" $a""e" &etween the cru" $eni" and the $u&i" to
reach the dor"al "urface of the cor$oral &odie". It run" &etween
the dor"al %ein and the dor"al $enile ner%e and with them attache"
to the under"ide of Buc# fa"cia +"ee *ig. -?/. A" it cour"e" to the
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glan", it gi%e" o4 ca%ernou" &ranche" and circumferential &ranche"
to the "$ongio"um and urethra. The rich &lood "u$$ly to the
"$ongio"um allow" "afe di%i"ion of the urethra during "tricture
re$air +De%ine and Angermeier, 77;/.
The "urgeon contem$lating $enile re%a"culari2ation mu"t &e
aware that the "enile arteries are hi*hly variable in their
branchin*) courses) and anastomoses +Bare et al, 77;/. It i"
not uncommon for a "ingle ca%erno"al artery to "u$$ly &oth cor$oral
&odie" or to &e a&"ent altogether. Alternati%ely, an acce""ory
$udendal artery may "u$$lement or com$letely re$lace &ranche"
of the common $enile artery. Thi" artery u"ually ari"e" from the
o&turator or inferior %e"ical arterie" and run" anterolateral to or
within the $ro"tate to reach the $eni" in the com$any of the
dor"al %ein. Thi" artery ha" &een identi'ed in 8 of 9 cada%eric
"$ecimen" +Bre2a et al, 77/ and noted at ;K of radical $ro"tatectomie"
+ola"ci# and 3al"h, 77</1 it" re"ection at $ro"tatectomy
may ad%er"ely a4ect $o"to$erati%e $otency +Drou$y et al,
777/.
At the base of the *lans) several venous channels
coalesce to form the dorsal vein of the "enis) 'hich runs
in a *roove bet'een the cor"oral bodies and drains into
the "re"rostatic "le$us +"ee *ig. -?/. The circum:e) %ein"
originate in the "$ongio"um and $a"" around the ca%erno"a to
meet the dee$ dor"al %ein $er$endicularly. They are $re"ent only
in the di"tal two third" of the $enile "haft and num&er 5 to 9.
Intermediary %enule" form from the ca%ernou" "inu"e" to drain
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into a "u&tunical ca$illary $le)u". The"e $le)u"e" gi%e ri"e to emi""ary
%ein", which commonly follow an o&li>ue $ath &etween the
layer" of the tunica and drain into the circum:e) %ein"
?? SCTION I = Anatomy
from the urethral meatu" to the anu" and re$re"ent" the line of
fu"ion of the genital tu&ercle". Dee$ to thi" ra$he, the "crotum i"
"e$arated into two com$artment" &y a "e$tum.
The dartos layer of smooth muscle is continuous 'ith
Colles) Scar"a) and the dartos fascia of the "enis +"ee *ig".
-; and -7/. The te"te" are "u"$ended &y their cord" in the
"crotal com$artment". A" the te"te" de"cend, they ac>uire co%ering"
from the layer" of the a&dominal wall, #nown a" the
spermatic fascia, that form $art of the "crotal wall +*ig. -<9/.
The e)ternal "$ermatic fa"cia deri%e" from the e)ternal o&li>ue
fa"cia and remain" 'rmly attached to the &order" of the e)ternal
ring. The crema"teric mu"cle and fa"cia ari"e from the internal
o&li>ue mu"cle and attach laterally to the inguinal ligament and
ilio$"oa" fa"cia and medially to the $u&ic tu&ercle. The internal
"$ermatic fa"cia i" a continuation of the tran"%er"ali" fa"cia. The
$arietal and %i"ceral tunica %aginali" "urround the te"ti" with a
me"othelium0lined $ouch and are deri%ed from the $eritoneum.
They are continuou" at the $o"terolateral &order of the te"ti" at
it" me"entery, where it i" ')ed to the "crotal wall. The te"ti" i"
al"o ')ed at it" lower $ole &y the gu&ernaculum. cca"ionally,
the me"entery and gu&ernaculum may &e de'cient, lea%ing the
te"ti" un')ed +&ell0cla$$er deformity/ and $redi"$o"ing to tor"ion
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of the cord.
The anterior 'all of the scrotum is su""lied by the
e$ternal "udendal vessels and the ilioin*uinal and *enitofemoral
nerves +"ee *ig. -</. The anterior %e""el" and ner%e"
ty$ically run $arallel to the rugae and do not cro"" the ra$he1 thu"
tran"%er"e or midline ra$he "crotal inci"ion" are mo"t hemo"tatic.
The &ac# of the "crotum i" "u$$lied &y the $o"terior "crotal
&ranche" of the $erineal %e""el" and ner%e" +"ee *ig. -;8/. In addition,
the $o"terior femoral cutaneou" ner%e +5/ gi%e" a $erineal
&ranch to "u$$ly the "crotum and $erineum +"ee *ig. -/. In
accordance with their origin, the "$ermatic fa"ciae ha%e a &lood
dor"olaterally. Hmi""ary %ein" in the $ro)imal third of the $eni"
join on the dor"omedial "urface of the ca%ernou" &odie" to form
two to '%e ca%ernou" %ein". At the hilum of the $eni", the"e %e""el"
$a"" &etween the crura and the &ul&, recei%ing &ranche" from
each, and join the internal $udendal %ein". Fal%e" are found in
the emi""ary, ca%erno"al, and dee$ dor"al %ein" and may thwart
attem$t" to re%a"culari2e the $eni" &y arterio%enou" ana"tomo"i"
+ohn, 77;/.
The dorsal nerves "rovide sensory innervation to the
"enis( The"e ner%e" follow the cour"e of the dor"al arterie" and
richly "u$$ly the glan" +"ee *ig. -?/. mall &ranche" from the
$erineal ner%e "u$$ly the %entrum of the $eni" near the urethra
a" far a" the glan" di"tally +Uchio et al, 777/. The"e ner%e" mu"t
&e ane"theti2ed when $erforming a $enile &loc# to num& the
%entrum of the $eni". The route of the ca%ernou" ner%e" ha" &een
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de"cri&ed. After $iercing the cor$oral &odie", they ramify in the
erectile ti""ue to "u$$ly "ym$athetic and $ara"ym$athetic inner%ation
from the $el%ic $le)u". Tonic "ym$athetic tone inhi&it"
erection. ara"ym$athetic ner%e" relea"e acetylcholine, nitric
o)ide, and %a"oacti%e inte"tinal $oly$e$tide, which cau"e the
ca%erno"al "mooth mu"cle and arterial rela)ation nece""ary for
erection +Burnett, 77</. It i" thought that during erection, the
"u&tunical %enule" are occluded &y &eing com$re""ed again"t the
nondi"ten"i&le tunica al&uginea. In"uOcient %enou" occlu"ion,
$articularly in %e""el" draining into the dee$ dor"al and ca%erno"al
%ein", i" thought to cau"e %a"culogenic im$otence.
Scrotum
The scrotal s%in is "i*mented) hair bearin*) devoid of
fat) and rich in sebaceous and s'eat *lands( It %arie" from
loo"e and "hiny to highly folded with tran"%er"e rugae, de$ending
on the tone of the darto" "mooth mu"cle. A midline ra$he run"
Int. $udendal a. *igure -;7. Arterial "u$$ly of the $eni".
Circum:e) a.
Ca%erno"al a.
Dor"al a.
Bul&ar a.
Circum:e) ca%erno"al a.
C3APT+ 4 = Anatomy of the Lower Urinary Tract and Male Genitalia ?8
the media"tinum te"ti", the $oint at which %e""el" and duct" tra%er"e
the te"ticular ca$"ule +"ee *ig. -;/. e$ta radiate from the
media"tinum to attach to the inner "urface of the tunica al&uginea
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to form 99 to 599 cone0"ha$ed lo&ule", each of which contain"
one or more con%oluted "eminiferou" tu&ule". Hach tu&ule i" U
"ha$ed and ha" a "tretched length of nearly meter. Inter"titial
+Leydig/ cell" lie in the loo"e ti""ue "urrounding the tu&ule" and
are re"$on"i&le for te"to"terone $roduction. Toward the a$ice" of
the lo&ule", the "eminiferou" tu&ule" &ecome "traight +tu&uli recti/
and enter the media"tinum te"ti" to form an ana"tomo"ing
networ# of tu&ule" lined &y :attened e$ithelium. Thi" networ#,
#nown a" the rete testis +*ig. -</, form" to 9 e4erent ductule"
and $a""e" into the large"t $ortion of the e$ididymi", the ca$ut.
@ere, the e4erent ductule" enlarge, &ecome more con%oluted, and
form conical lo&ule". The duct from each lo&ule drain" into a
"ingle e$ididymal duct, which wind" a$$ro)imately ? m within
the '&rou" "heath of the e$ididymi" to form it" &ody and tail.
A" the duct a$$roache" the tail, it thic#en" and "traighten" to
&ecome the %a" deferen".
The "$ermatic cord i" com$o"ed of the %a" deferen", te"ticular
%e""el", and "$ermatic fa"ciae. A" di"cu""ed in Cha$ter , the te"ticular
arterie" ari"e from the aorta and tra%el in the intermediate
"tratum of the retro$eritoneum to reach the internal inguinal ring.
!ateral to the internal in*uinal rin*) the attachments of
"u$$ly +crema"teric, %a"al, te"ticular/ "e$arate from that of the
"crotal wall. *ournier gangrene u"ually doe" not in%ol%e the"e
"tructure", and they may &e "$ared during dX&ridement.
Perineal !ym"hatics
The "enis) scrotum) and "erineum drain into the in*uinal
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lym"h nodes( These nodes may be divided into su"er<cial
and dee" *rou"s) 'hich are se"arated by the dee"
fascia of the thi*h #fascia lata&( In relation to the e)ternal
$udendal, "u$er'cial inferior e$iga"tric, and "u$er'cial circum:e)
iliac %e""el", the "u$er'cial node" lie at the "a$henofemoral junction.
At the "a$henou" o$ening +fo""a o%ali"/ in the fa"cia lata, the
greater "a$henou" %ein join" the femoral %ein and the "u$er'cial
node" communicate with the dee$ grou$. Mo"t of the dee$ inguinal
node" lie medial to the femoral %ein and "end their e4erent"
through the femoral ring +&eneath the inguinal ligament/ to the
e)ternal iliac and o&turator node". !u"t out"ide the femoral ring,
a large node +Clo>uet or 6o"enmuller node/ i" con"i"tently $re"ent.
The scrotal lym"hatics do not cross the median ra"he
and drain into the i$"ilateral "u$er'cial inguinal lym$h node".
Lym$hatic" from the "haft of the $eni" con%erge on the dor"um
and then ramify to &oth "ide" of the groin. Tho"e of the glan" $a""
dee$ to Buc# fa"cia dor"ally and drain to "u$er'cial and dee$
grou$" in &oth "ide" of the groin. Direct lym$hatic channel" from
the glan" to the $el%ic node", which &y$a"" the inguinal node",
ha%e &een $ro$o"ed &y anatomi"t"1 howe%er, clinical "tudie" ha%e
not con'rmed their e)i"tence. ther "tudie" ha%e "ugge"ted that
all $enile lym$hatic drainage $a""e" through "entinel node",N
which lie medial to the "u$er'cial inferior e$iga"tric %ein". Clinical
"tudie" ha%e al"o called thi" "$eculation into >ue"tion +Catalona,
7/. The $erineal "#in and fa"ciae drain into "u$er'cial
inguinal node"1 the "tructure" of the "u$er'cial $ouch li#ely drain
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into the "u$er'cial and dee$ inguinal node grou$".
Testes
The te"te" are ; to < cm long, 5 cm wide, and .< cm dee$ and
ha%e a %olume of 59 mL. They are enclo"ed in a tough ca$"ule
com$ri"ing +/ the %i"ceral tunica %aginali"1 +/ tunica al&uginea,
with collagenou" and "mooth mu"cle element"1 and +5/ the tunica
%a"culo"a. The e$ididymi" attache" to the $o"terolateral a"$ect of
the te"ti". Beneath it, the tunica al&uginea $roject" inward to form
*igure -<9. crotum and it" layer". +*rom an"#y B. 6e%iew of gro"" anatomy. ?th
ed. (ew Eor# McGraw0@ill1 78. $. ;5./
*igure -<. Te"ti" ultra"ound demon"trating rete te"ti" (arrow).
? SCTION I = Anatomy
77</. Intracta&le orchialgia may re"$ond to ane"the"ia of the
$el%ic $le)u" +orn et al, 77;/. Intriguingly, "ome a4erent and
e4erent ner%e" cro"" o%er to the contralateral $el%ic $le)u"
+Taguchi et al, 777/. Thi" neural cro""0communication might
e)$lain how $athologic $roce""e" in one te"ti" +e.g., tumor or
%aricocele/ may a4ect the function of the contralateral te"ti". The
genital &ranch of the genitofemoral ner%e "u$$lie" "en"ation to
the $arietal and %i"ceral tunica %aginali" and the o%erlying
"crotum.
.emale 7ro*enital Trian*le
The vestibule of the va*ina runs vertically throu*hout
the len*th of the uro*enital trian*le( The la&ia majora form
it" lateral "ide" and fu"e anteriorly a" the hood of the clitori". The
"u&cutaneou" fat $ad of the mon" $u&i" continue" $o"teriorly in
the la&ia majora to frame the %e"ti&ule. The la&ial fat $ad" recei%e
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&lood "u$$ly from the e)ternal $udendal %e""el" and may &e
rai"ed on the"e %e""el" a" a rotational :a$ for re$air of %e"ico%aginal
or urethro%aginal '"tula" +*ig. -<</. The urethra enter" the
%e"ti&ule &etween the clitori" and the %agina.
The structure of the su"er<cial "ouch is similar to
that of the male +*ig. -<?/. The crura of the clitori" attach to
the inferior i"chio$u&ic rami, "urrounded &y the i"chioca%erno"u"
mu"cle", and con%erge to form the &ody of the clitori". The %e"ti&ular
&ul&" lie to either "ide of the %aginal %e"ti&ule, co%ered &y
the &ul&o"$ongio"u" mu"cle". A" homologue" of the $enile &ul&,
they are com$o"ed of erectile ti""ue and meet anteriorly to form
the glan" of the clitori". The %e"ti&ular gland" are dee$ to the
%e"ti&ular &ul&" &ut, unli#e the &ul&ourethral gland" in the male,
are "u$er'cial to the $erineal mem&rane. Their duct" tra%el cm
to o$en in the %aginal %e"ti&ule on the $o"teromedial "ide" of the
la&ia minora. The $erineal mem&rane, $ierced in it" center &y the
%agina, i" le"" well de%elo$ed than that of the male. The inner%ation,
&lood "u$$ly, and lym$hatic drainage of the e)ternal genitalia
and "u$er'cial $ouch are "imilar to tho"e de"cri&ed in the
male.
the intermediate stratum form the lateral s"ermatic
fascia( The"e attachment" can &e ta#en down at orchido$e)y to
gain cord length. At the internal ring, the %e""el" are joined &y the
genital &ranch of the genitofemoral ner%e, ilioinguinal ner%e,
crema"teric artery, and %a" deferen" and it" artery.
In its course to the testis) the testicular artery branches
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into an internal artery and an inferior te"ticular artery and into a
ca$ital artery to the head of the e$ididymi" +"ee *ig. -/. The
le%el of thi" &ranching %arie" and ha" &een noted to occur within
the inguinal canal in 5K to K of ca"e" +Bec# et al, 771 !arow
et al, 77/. 3hen $erforming an inguinal %aricocelectomy, the
"urgeon mu"t remem&er that there may &e two or three arterial
&ranche" at thi" le%el +@o$$" et al, 995/. A rich arterial ana"tomo"i"
occur" at the head of the e$ididymi", &etween the te"ticular
and the ca$ital arterie", and at the tail &etween the te"ticular,
e$ididymal, crema"teric, and %a"al arterie" +"ee *ig. -/. The
te"ticular arterie" enter the media"tinum and ramify in the tunica
%a"culo"a, $rinci$ally in the anterior, medial, and lateral $ortion"
of the lower $ole and the anterior "egment of the u$$er $ole +*ig.
-< on the H)$ert Con"ult we&"ite and *ig. -<5/. Thu" $lacement
of a traction "uture through the lower $ole tunica al&uginea
ri"#" damaging the"e im$ortant "u$er'cial %e""el" and de%a"culari2ing
the te"ti" +!arow, 77/. Te"ticular &io$"y "hould &e carried
out in the medial or lateral "urface of the u$$er $ole, where the
ri"# of %a"cular injury i" minimal.
The testicular veins form several hi*hly anastomotic
channels that surround the testicular artery as the
"am"iniform "le$us( Thi" arrangement allow" countercurrent
heat e)change, which cool" the &lood in the te"ticular artery. At
the le%el of the inguinal canal, the %ein" join to form two or three
channel" and then a "ingle %ein that drain" into the inferior %ena
ca%a on the right and the renal %ein on the left. The te"ticular
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%ein" may ana"tomo"e with the e)ternal $udendal, crema"teric,
and %a"al %ein" +*ig. -<;/. The"e connection" can allow %aricocele"
to recur after a&lati%e $rocedure". Te"ticular lym$hatic %e""el"
drain to the $ara0aortic and interaortoca%al node" a" detailed in
Cha$ter .
Visceral innervation to the testis and e"ididymis
travels by t'o routes( A "ortion arises in the renal and
aortic "le$uses and travels 'ith the *onadal vessels( Additional
gonadal a4erent and e4erent ner%e" cour"e from the $el%ic
$le)u" in a""ociation with the %a" deferen" +6auchenwald et al,
*igure -<5. Do$$ler ultra"ound of te"ti" demon"trating
"$o#eli#e radiation of te"ticular %e""el" originating from the
media"tinum te"ti".
*igure -<;. Fenou" drainage of the te"ti" and e$ididymi". (ote
connection" &etween the $am$iniform $le)u" and the "a$henou",
internal iliac, and e)ternal iliac %ein".
Int.
"$ermatic %.
Int. ring.
H)t. "$ermatic %.
Inf. e$iga"tric %.
u$. e$iga"tric %.
u$. circum:e) %.
u$. and dee$
$udendal %.
Int. *emoral %.
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$udendal %.
Te"ti"
am$iniform
$le)u"
@y$oga"tric %. H)t.
ring
Fa"
u$. %e"ical %.
H)t. iliac %.
Crema"teric %.
*igure -<<. Arterie" and ner%e" of the female $erineum. +*rom Doherty MG. Clinical
anatomy of the $el%i". In Co$eland L!, editor.
Te)t&oo# of gynecology. hiladel$hia 3B aunder"1 775. $. <./
Inguinal
ligament
u&i"
tu&ercle
Ilioinguinal n.
H)t. $udendal a.
Clitoral &ranch,
int. $udendal a.
erineal &ranch,
$o"t. cutaneou"
ner%e of thigh
Int. $udendal
%e""el" and ner%e"
Inf. rectal a.
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I"chiorectal fo""a
Tran"%er"e $erineal %e""el
o"t la&ial %%.
#in, car$a fa"cia,
Colle" fa"cia
H)t. $udendal a., %.
6ound ligament
*igure -<?. *emale "u$er'cial $erineal
$ouch. n the left "ide, the mu"cle" ha%e
&een remo%ed to "how the %e"ti&ular &ul&
and Bartholin gland. +*rom 3illiam" L,
3arwic# 6. Gray" anatomy. 5<th Briti"h ed.
hiladel$hia 3B aunder"1 785. $. 5?;./
I"chioca%erno"u"
Bul&o"$ongio"u"
Urethral ori'ce
Faginal ori'ce
Tran"%er"u" $erinei
"u$er'ciali"
Le%ator ani
Gluteu" ma)imu"
erineal &ody
acrotu&erou"
ligament
Greater %e"ti&ular
gland
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Inferior fa"cia
of urogenital
dia$hragm
Bul& of the
%e"ti&ule
&turator
foramen
Cru" of clitori"
Body of clitori"
Body of $u&i"
u&ic "ym$hy"i"
$hincter ani e)ternu"
6amu" of
i"chium
89 SCTION I = Anatomy
S7GGST, +A,INGS
DeLancey !L. Anatomy and &iomechanic" of genital $rola$"e. Clin &"tet
Gynecol 77515?78-797.
@inman * !r. Atla" of uro"urgical anatomy. hiladel$hia 3B aunder"1
775.
Myer" 6. 6adical $ro"tatectomy $ertinent "urgical anatomy. Atla" Urol
Clin (orth Am 77;1-.
Uhlenhuth H. ro&lem" in the anatomy of the $el%i". hiladel$hia !B Li$$incott1
7<5.
3illiam" L, 3arwic# 6, Dy"on M, Banni"ter L@. Gray" anatomy. 58th ed.
(ew Eor# Churchill Li%ing"tone1 77.
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+.+NCS
The com$lete reference li"t i" a%aila&le online at www.e)$ertcon"ult.com.