Obstetric

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Obstetric gynecologic anatomyJohn
Fitzsimmons, MD

• Bones Ligaments
• Muscles
• Nerves
• Blood vessels
• Viscera
• Pelvic fascia, ligaments, and spaces
• Ureter

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• Pelvic Ligaments
• Sacrotuberous
• Sacrospinous landmark for ID of the pudendal
  n. the internal pudendal a
• Obturator membrane not seen here
• anterior and posterior sacroiliac

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• Pelvic muscles
• 2 distinct functional groups
• true pelvic muscles
• make up the pelvic diaphragm
• muscles of the lower limb
• Piriformis and the obturator internus
• Pelvic Diaphragm
• composed of the Levator ani and Coccygeus muscles
  together with their fascial layers
• stretches across the pelvis, closing the
  abdominopelvic cavity inferiorly, providing
  support

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• Levator ani
• broad, thin muscle - most of the pelvic floor
• 3 muscles - pubococcygeus, puborectalis, and
  iliococcygeus
• the two sides are separated by the anal canal,
  urethra, and vagina in the midline
• function as a single sheet forming the principle
  part of the pelvic diaphragm
• arise from the inner aspect of the superior pubic
  ramus anteriorly, the ischial spine posteriorly,
  and the tendinous arch of the levator ani
• tendinous arch is a thickened band of obturator
  fascia
• This tough connective tissue arch is often used
  in surgery for anchoring sutures

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• Coccygeus
• triangular muscle, which lies just dorsal to the
  levator ani muscles
• ischial spine to the coccyx and sacrum
• the most posterior portion of the pelvic
  diaphragm
• Laterally its fibers blend with the sacrospinous
  ligament, which forms the inferior limit to the
  greater sciatic foramen
• pudendal n. internal pudendal a, inferior
  gluteal a exit the pelvis between the piriformis
  coccygeus

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• Piriformis
• arises on the posterior wall of the pelvis from
  the sacrum and then passes inferolaterally to
  exit the greater sciatic foramen
• forms a bed upon which lies the sacral plexus
  and medial to that, the branches of the internal
  iliac
• branches of the sacral plexus leave the pelvis
  with the piriformis and identification of several
  arteries are determined by their relationship to
  the piriformis and the sacral plexus

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• Obturator Internus
• covers a large area on the lateral internal
  surface of the coxal bone below the pelvic brim
• arises from the pelvic surface of the obturator
  membrane superiorly tapers to a narrow tendon
  in the lesser sciatic foramen where it exits the
  pelvic cavity to reach the greater trochanter
• medial surface is covered by obturator fascia
• many of the branches of the anterior division of
  the internal iliac lie medial to the obturator
  internus
• obturator canal passes through the fibers of this
  muscle near its origin

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Neurovasculature

• Nerves of the posterior abdominal wall and their
  course
• Subcostal, iliohypogastric, ilioinguinal, lateral
  femoral cutaneous, genitofemoral, femoral,
  obturator and autonomics
• Abdominal pelvic vessels
• Major abdominal branches of the aorta
• Branches of the internal iliac

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• Abdominal Aorta
• General
• Runs on the left anterior aspect of the vertebral
  column
• ends by bifurcating in front of the body of L4
  into the common iliac arteries
• Relations
• Ventral
• lesser omentum and stomach in its superior
  portion
• the pancreas, 1st part of the duodenum, and the
  splenic and left renal veins in its middle
  portion
• small intestines and mesentery in it inferior
  portion
• IVC is in contact with the aorta on the right
• several arterial branches, either unpaired
  anterior branches, or laterally placed paired
  branches
• Celiac Trunk
• SMA
• Renal
• Gonadal
• IMA
• Lumbar

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Renal Arteries - two large trunks, which arise
from the sides of the aorta just caudal to the
SMA, generally at the level of the L1 L2 disk
space - right is longer than the left, due to the
aortas position on the left side of the body
passes behind the IVC, right renal vein, head of
the pancreas, the descending aorta - left
passes behind the left renal vein, body of the
pancreas, splenic inferior mesenteric v - each
usually branches into several smaller renal
arteries as well as giving branches to the
adrenals and ureters - 1 or 2 accessory renal
arteries may be found (23) if this is below
the main renal artery the accessory branch passes
anterior to the ureter important to keep in
mind when following the course of the ureter up
to the hilum
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• Ovarian arteries
• - two long slender arteries arising from the
  ventral surface of the aorta just caudal to the
  renal arteries
• - may arise as a single artery or as a branch of
  the renal artery
• - each passes caudally and laterally on the
  anterior surface of the psoas major
• each crosses obliquely over the ureter, lateral
  to and slightly above the level of the aortic
  bifurcation
• almost parallel the ureter towards the pelvic
  brim
• once at the superior aperture of the lesser
  pelvis the artery passes medially within the
  suspensory ligament of the ovary

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Ovarian arteries - small branches are given to
the ureter and the uterine tube and one passes
onto the uterus to anastamose with the uterine
artery - other branches continue inferiorly in
the round ligament to the integument of the
perineum - accompanied by their veins through
most of their course - the veins originate from
the pampiniform venous plexus, which surrounds
the ovarian artery in the pelvis - left ovarian
vein drains into the L renal vein and the right
ovarian vein drains into the IVC
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• Vaginal artery
• corresponds to the inferior vesical artery in
  the male
• arises from the uterine artery or the anterior
  division if it is from the latter it generally
  arises below the obturator artery
• - Generally 2 but there may be 3 or 4
• descends medially in the cardinal ligament and
  divides into branches to the vagina
• also supplies the posterior and inferior parts of
  the bladder
• - anastamose with branches of the uterine artery
  descending

• Middle Rectal artery
• may arise off the anterior division or maybe off
  the internal pudendal artery
• passes infero-medially along the levator ani
  towards the rectum enclosed within a condensation
  of parietal pelvic fascia forming the lateral
  rectal ligament
• branches that distribute to the rectum, the base
  of the bladder, and the upper vagina.

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• Uterine artery
• - arises -- medial surface of the anterior
  division of the internal iliac
• - 3rd branch following the umbilical and
  obturator arteries
• - descends on the lateral pelvic wall and
  posterior edge of the ovarian fossa easily
  isolated from the surrounding tissue here
• passes medially on the levator ani towards the
  uterine cervix and
• 2cm from the cervix it passes over top of the
  ureter within the cardinal ligament
• easily identified tortuous course
• - anastomosis with the vaginal ovarian arteries
  on the lateral edges of the uterus
• - accompanied by an extensive venous plexus,
  which drains both the vagina and the uterus

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• The deep veins of the pelvis can be problematic
  when lacerated
• retroperitoneal dissection of the lateral wall
  and around the sacrum makes hemorrhage a
  significant risk
• bifurcation of the iliac vessels is particularly
  dangerous because of the proximity of the
  hypogastric (internal iliac) vein and its
  branches
• lateral sacral veins disappear into the foramina
  and laceration of them is extremely difficult to
  repair as they can not be accessed in the
  foramina and are held open by their attachment to
  the foraminal walls
• keep dissection anterior to the presacral fascia
• the obturator fossa is complex because of the
  extreme variation of the venous pattern (and even
  the arterial pattern)

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Pelvic Viscera

• Bladder
• Sigmoid colon and rectum
• Uterus and cervix
• Vagina
• Ovaries and ovarian tubes

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• Bladder
• separated from the pubic bones by the retropubic
  space
• subperitoneal lying against the anterior pelvic
  wall just in front of the uterus
• anatomically divided into an apex, body, fundus,
  base but physiologically into a dome (apex,
  body, fundus) the base
• dome (detrusor) has ß-adrenergic receptors which
  favors voiding (cholinergic response)
• Base (trigone sphincter) has a-adrenergic
  receptors, favors continence (adrenergic)
• corners of the trigone receive the ureters and
  then it tapers into the urethra where the bladder
  rests on the upper vagina
• arterial supply
• superior vesicle a. to the anterosuperior portion
• vaginal a. to the posteroinferior portion
• Lymphatics
• superior surface to the internal iliac nodes
• fundus to the internal iliac nodes
• neck to sacral common iliac nodes

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Sigmoid Colon and Rectum

• begins its s-shaped curve at the L iliac crest
  and descends towards the pelvic brim
• middle portion has a definite mesentery (not
  retroperitoneal)
• enters the pelvis straightens its course
  anterior to the sacrum and becomes the rectum
  (retroperitoneal)
• rectum extends from the pelvic brim to the anus
  behind the vagina
• covered by peritoneum anteriorly until it
  descends below the cul-de-sac where the
  peritoneum reflects back up on the posterior
  surface of the vagina

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• Uterus
• thick walled, pear-shaped, hollow muscular organ
  supported between the bladder and rectum in the
  pelvic cavity
• develops thru fusion of the lower end of the
  Mullerian ducts
• divided into three parts a fundus, a corpus, and
  a cervix
• fundus (apex) corpus (body) form the upper
  muscular portion
• cervix the lower fibrous portion connecting
  with the vagina
• usually in an anteverted anteflexed position
  this puts it weight above the bladder

• RELATIONSHIPS
• Anterior/inferior vesicouterine pouch
  superior surface of the bladder
• Posterior rectouterine pouch (of Douglas) with
  loops of bowel
• Lateral broad cardinal ligaments the
  uterosacral ligaments
• ureters uterine arteries in the cardinal
  ligaments on either side of the supravaginal
  cervix
• wall is primarily muscular
• muscle fibers are arranged in a criss-cross
  pattern and diagonally across each other

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• Uterine cervix
• the inferior portion of the uterus that connects
  the uterine cavity to the vaginal canal
• portio vaginalis the distal portion that
  protrudes into the vaginal canal
• lumen is coated with nonkeratinized squamous
  epithelium
• mucosal lining transitions into the columnar
  epithelium of the endocervical canal at the
  external os
• it is this area of transition that carries the
  greatest risk of malignant transformation

• portio supravaginalis the proximal portion that
  extends above the vagina to the corpus
• wall of the cervix is a dense fibrous connective
  tissue with a small amount of smooth muscle
• smooth muscle lies peripherally and is continuous
  with both the myometrium and the muscle of the
  vaginal wall
• connective tissue is continuous with that of the
  cardinal and uterosacral ligaments, and the
  pubocervical fascia
• smooth muscle ( it fibrous CT) is easily
  dissected off the fibrous cervix the tissue to
  which the cardinal uterosacral ligaments attach

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• Vagina
• a flattened, distensible musculomembranous canal
  approx. 3in. in length
• Vulva to pouch of Douglas
• through the urogenital and pelvic diaphragms and
  hence lies partly in the pelvis and partly in the
  perineum
• Attachments to the lateral walls flatten it from
  anterior to posterior
• attachments
• cardinal ligaments superiorly
• arcus tendineus laterally in the middle portion
• lower 1/3rd pubic bones anteriorly perineal
  body posteriorly
• bent about 120o by the anterior traction of the
  levator ani muscles at the junction of its middle
  lower thirds
• cervix extends down back into the vaginal canal
• anterior and posterior fornices and lateral
  vaginal sulci
• devoid of peritoneum except at the Pouch of
  Douglas

RELATIONS anterior - upper 1/3rd
vesicovaginal space/bladder - lower 2/3rds
urethra posterior - upper 1/3rd pouch of
Douglas - middle 1/3rd rectum - lower
1/3rd perineal body lateral - upper 1/3rd
ureter cardinal ligaments - middle 1/3rd
levator ani - lower 1/3rd UG diaphragm
vestibular bulb
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• Blood supply to the vagina
• uterine a. to the upper portions
• vaginal internal pudendal a. to the middle
  lower portions
• significant anastamosis between these vessels
• venous plexus with anastomosis with the uterine
  plexus drains to the internal iliac v.
• LYMPHATICS
• superior internal external iliac nodes
• middle internal iliac nodes
• lower sacral, common iliac superficial
  inguinal nodes
• INNERVATION
• uterovaginal plexus from the inferior hypogastric
  plexus supplies all visceral innervation to the
  upper ¾ths and the uterus
• somatic innervation to the lower portion is via
  the deep perineal branch from the pudendal

• Blood supply to the uterus
• 6 (3 on each side) sources of blood
• Uterine branch of the internal iliac
• Ovarian branch of the aorta distal branches
  reach the uterus through the ovarian ligaments
  after supplying the ovaries
• vaginal branch of the internal iliac
• All of these must be ligated when performing a
  hysterectomy

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• Vaginal fascia and support
• middle portion of develops significant lateral
  attachments called the arcus tendineous fascia
  pelvis
• pubocervical fascia arcus tendineous fascia
  pelvis, attachments to the cervix, the cardinal
  ligaments, and the perineal body through the
  perineal membrane
• lower 1/3rd attached to the pubic bones via the
  perineal membrane, to the perineal body
  posteriorly, and the levator ani laterally
• lower attachments are the strongest usually
  preserved even in complete vaginal prolapse

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• The Ovary
• Firm, almond shaped organ
• surface devoid of peritoneum - ovum is released
  into the peritoneal cavity
• suspended from the posterior sheet of the broad
  ligament by the mesovarium
• embraced anteriorly and laterally by the uterine
  tube
• mesovarium contains the ovarian vessels and
  nerves
• mobile in its position
• generally lies within the ovarian fossa against
  the internal iliac artery and the ureter
• obturator nerve and artery can be found in the
  floor of the ovarian fossa
• medial surface faces the pararectal fossa and the
  rectouterine pouch
• Supported by the
• suspensory ligament of the ovary, the lateral
  continuation of the broad ligament that envelops
  the ovarian vessels and nerves
• ligament of the ovary, which is within the broad
  ligament

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• Ovarian blood supply is from two sources
• ovarian arteries
• a branch of the uterine artery
• anastamose with each other in the mesovarium
• arteries are accompanied by a plexus of veins
• lymphatic drainage is to the para-aortic,
  lumbar, nodes
• Nerve supply is via the aortic and renal
  plexuses pass to the ovary with the ovarian
  artery in the suspensory ligament.

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• Fallopian Tubes
• extending from the uterus to the ovary and
  connecting the uterine cavity to the peritoneal
  cavity
• surrounded by peritoneum along the upper margin
  of the broad ligament as its anterior and
  posterior lamina come together
• portion of the broad ligament between the tube
  and the mesovarium is called the mesosalpinx
• passes anterior to the ovary and then posteriorly
  around the lateral pole of the ovary
• 4 named parts of the tube 1) the uterine part
  (intramural), 2) Isthmus, 3) Ampulla, 4)
  Infundibulum with fimbriae.
• ovarian fimbria
• Neurovasculature
• ovarian and uterine arteries
• Lymphatic drainage is to the aortic nodes
• Nerve supply is derived from the uterine and
  ovarian plexuses and ultimately from T11-L1.

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Pelvic FasciaOccurs in three forms
(consistencies)

• Membranous fascia
• Parietal and visceral fascia
• Loose areolar fascia
• Endopelvic fascia of pelvic spaces
• Fibroareolar fascia
• Endopelvic fascial ligaments (neurovascular
  laminae)

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What is a ligament?

• Ligaments of joints
• gross, strong, anchoring CT bands
• Skin ligaments
• macro- or microscopic anchoring CT bands
• Embryologic remnants
• Serous (pleura/peritoneal) ligaments
• enclosing neurovascular structures
• empty folds or double serous sheets
• Extraperitoneal condensations of CT
• Extraperitoneal (fatty) bundles of neurovascular
  structures and ducts, ensheathed in fatty CT with
  smooth muscle fibers. Amt. of CT is variable.

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Membranous pelvic fascia

• 1. parietal pelvic fascia
• the variable thickness layer of membranous fascia
  that covers the deep/pelvic surface of the
  muscles forming the walls and floor of the pelvis
  
• may be named for the muscle the tissue covered
• Obturator fascia
• Tendinous arch of the obturator fascia
• extends, in a curvilinear fashion, from the
  posterolateral pubis to the ischial spine
• continuous superiorly with the transversalis and
  iliopsoas layers of fascia

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Membranous pelvic fascia

• 2.visceral pelvic fascia
• that membranous fascia that covers the pelvic
  organs forming the adventitial layer of each
• named for the structure it covers
• vesical, rectal, prostatic, uterovaginal
• where an organ passes through the pelvic
  diaphragm the visceral fascia merges with the
  pelvic fascia
• Some structures seem have a common fascia
• pubovesical (pubovesicocervical) fascia
• Tendinous arch of the pelvic fascia
• bilateral band extending from the pubic bones to
  the ischial spine where the visceral parietal
  layers meet

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Membranous Visceral and Parietal Pelvic Fascia
Visceral fascia surrounding bladder prostate
Areolar endopelvic fascia in retropubic
(prevesical) space
Visceral fascia surrounding rectum
Continuity of visceral and parietal fascia (arcus
tendineus of pelvic fascia)
Parietal fascia surrounding pelvic diaphragm
(levator ani muscle)
Perineal body
Plate 338A/348A
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Membranous Visceral and Parietal Pelvic Fascia
Parietal fascia
Visceral fascia
Plate 341/351
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Endopelvic fascia of spaces

• loose areolar tissue ? connective tissue packing
  of the pelvic organs
• forms easily dissected potential spaces
• a. retropubic (prevesical and paravesical)
• b. retrorectal (presacral)
• continuous with both the parietal and visceral
  layers of fascia
• the looseness of this tissue also allows for
  expansion of the surrounded organ (i.e. bladder,
  uterus)

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Endopelvic fascial ligaments

• do not appear much different grossly but have
  much more collagen and elastic tissue making
  these regions more fibrous in consistency
• hold the viscera to the lateral pelvic walls
  and carry neurovascular structures to from the
  viscera
• examples are the cardinal ligaments in females or
  rectovesical septum in males

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Peritoneal reflections, spaces, pouches
parietal peritoneum covers the inner surface of
the abdominal wall and is continuous with the
visceral peritoneum on the pelvic viscera
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• Cleavage planes and retroperitoneal spaces
• Allow viscera to expand independently and for
  easy blunt dissection
• spaces are filled with either areolar CT or
  adipose tissue contain the major neural,
  vascular, and lymphatic supply of the pelvic
  viscera

• Prevesicle space (of Retzius)
• between the bladder anterior pelvic wall
• extends dorsolaterally to the cardinal ligaments
• bound laterally by the bony pelvis
• separated from the vesicovaginal space by a
  portion of the cardinal ligaments
• contains the
• dorsal clitoral vessels
• obturator vessels n.
• lower urinary tract vessels n.
• iliopectineal band, a thickened band of periosteum

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• Vesicovaginal vesicocervical spaces
• - the space between the lower urinary tract the
  genital tract
• - lower margin is where the urethra and vagina
  fuse
• superior margin is peritoneum as it reflects from
  the posterior wall of the bladder onto the
  anterior wall of the cervix
• this reflection of peritoneum forms the
  uterovesical pouch

Rectovaginal space - begins at the apex of the
perineal body and extends to the cul-de-sac
(Pouch of Douglas) - separated laterally from the
pararectal space by extensions of the cervical
and uterosacral lig
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Pelvic connective tissue, ligamentous supports,
cleavage planes

• pelvic viscera are connected to the lateral wall
  of the pelvis by their adventitial layers
  thickenings of the fascia of the pelvic muscles
• these condensations of fascia have become
  supportive in nature in addition to conveying
  neurovasculature
• consists of a network of collagen elastin
  fibers that are an extension of the adventitia of
  the viscera muscles (endopelvic fascia)
• portions of it may contain significant amounts of
  smooth muscle (pubocervical fascia)

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• 6 named ligamentous supports of the female pelvic
  viscera
• broad ligaments
• round ligaments
• infundibulopelvic ligaments
• uterosacral ligaments
• cardinal ligaments
• ovarian ligaments
• other support structures (for the uterus)
• Muscular floor
• Anteverted position of uterus
• Parametrium the connective tissue alongside the
  uterus extends between the layers of the broad
  ligament
• Paracolpium - the connective tissue alongside the
  vagina

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Broad Ligaments

• Ovaries migrate from lateral wall during
  development and carry peritoneum with them
• two peritoneal layers with a fatty fibrous
  tissue, (Parametrium), in between
• layers diverge at the uterus to become the
  visceral peritoneum
• layers separate inferiorly and laterally to cover
  the floor and side wall of the pelvis
• 2 layers continuous with each other superiorly
  and form a free upper border
• mesometrium main component
• mesovarium supports the ovary
• Mesosalpinx support the uterine tube

• Ovarian Ligaments
• fibromuscular cord enveloped between the 2 layers
  of the broad ligament at the upper free edge
• extends from the uterine pole of the ovary to the
  uterus

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• Round Ligaments
• true ligamentous fibromuscular cords
• pass from the upper, lateral portion of the
  uterus to the inguinal ring
• enclosed within the broad ligament
• cross over the external iliac vessels and the
  psoas major muscle in their course
• Help maintain the anteverted position of the
  uterus with a weakness resulting in the uterus
  falling back into the pelvic cavity and into the
  vagina (uterine prolapse). This is debatable

• Infundibulopelvic Ligaments (Suspensory Ligaments
  of the Ovary)
• extend from the lateral end of the ovary to the
  pelvic wall
• fibers are continuous with those of the Broad
  Ligament
• Contain the ovarian vessels and nerves
• passes anteriorly over the external iliac vessels
  to blend with the fascia and peritoneum covering
  of the psoas major

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Uterosacral Ligaments - conveniently described as
separate ligaments actually a posterior
inferior extension of the Cardinal Ligaments -
thick fibromuscular bands predominantly smooth
muscle intermixed with autonomic nerves, CT,
vessels - form the Rectouterine folds - attached
to the sides of the cervix and vaginal fornices
anteriorly - pass back around the rectum to the
sacrum - serve to hold the cervix up and back to
help maintain the anteverted position of the
uterus

• Cardinal Ligaments (Transverse cervical
  ligaments, or Mackenrodts ligaments)
• bases of the broad ligaments
• continuous with the uterosacral ligaments
• - attach the cervix vagina to the lateral
  pelvic wall near the greater sciatic foramen
• - consist of perivascular CT nerves around the
  uterine artery veins the ureter
• - it is within this ligament that the ureter is
  most susceptible to injury during surgery
• - help suspend the cervix and uterus, the upper
  portion of the vagina, to the pelvic walls

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Ureter

• Embryology
• 4th week of development - cloaca becomes divided
  by the urorectal septum
• septum completely separates the rectum from the
  urogenital sinus by the 8th week
• urogenital sinus later develops into the urethra,
  bladder and the lower portion of the vagina in
  the female
• 5th week - mesonephric ducts from above join the
  cloaca ureteric buds begin as a dorsal outgrowth
  of the mesonephric duct near its entry into the
  cloaca
• Each ureteric bud elongates and develops into a
  ureter

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• Ureter
• 3 anatomic layers
• Transitional epithelium lining the lumen
• Smooth muscle, circular, longitudinal, and
  spiral, to provide regular and efficient
  peristalsis
• Adventitial sheath this surrounds the ureter
  and contains and protects its blood vessels
• abdominal and pelvic portions
• abdominal ureter - embedded in the subserous
  fascia, crosses the psoas major as it descends
  towards the pelvis
• crossed by the gonadal vessels
• right ureter is usually covered by the descending
  part of the duodenum
• Near the superior aperture of the pelvis it
  passes dorsal to the inferior part of the root of
  the mesentery
• left ureter
• passes behind the sigmoid colon and its mesentery
  near the pelvic brim
• ureters cross the common iliac bifurcation to
  enter the pelvis

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• Pelvic Ureter
• initially runs caudally on the posterolateral
  wall of the pelvic cavity, along the anterior
  border of the greater sciatic notch
• lies ventromedial to the internal iliac artery
  and medial to the obturator nerve, and branches
  of the Internal Iliac artery
• Lies in the ovarian fossa
• lateral to the pouch of Douglas within the
  uterosacral ligament
• turns medially and ventrally towards the angle of
  the bladder within the rectouterine fold and then
  in the lateral cervical ligament
• passes beneath the uterine artery and vein about
  1.5cm lateral to the cervix at the level of the
  internal cervical os (this can vary markedly with
  pathologiy)

• travels in a preformed canal to which its
  adventitia is connected to by loose connective
  tissue so it is NOT in direct contact with
  vessels cleavage plane between the canal and the
  adventitia
• possible to dissect out the ureter without injury
  and unnecessary hemmorhage.
• continues forward and medial, in the
  vesicouterine ligament, and passes in front of
  the vagina surrounded by the vesicle nerve plexus
  to enter the posterolateral aspect of the bladder
• empties into the bladder about 1.5cm below the
  level of the anterior lip of the cervix (renal
  calculus may be palpated vaginally here)

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• Identifying the ureter
• usually conveniently identified in its
  retroperitoneal location as it crosses the iliac
  vessels near the bifurcation
• Here it tends to elevate the thin and
  transparent peritoneum and is both visible and
  palpable, unless the peritoneum is thickened or
  involved in a disease process
• On the left it may be obscured by the sigmoid
  colon
• can usually be followed from the pelvic brim to
  where it disappears under the uterine artery and
  into the tunnel through the cardinal ligament
• on the pelvic wall peristalsis may be seen
• simply stroking the ureter longitudinally can
  stimulate peristalsis
• important for the surgeon to understand the
  ureters close proximity to the cervix and vaginal
  fornices as it passes medially to enter the
  bladder as well as its proximity to vasculature
  such as the uterine artery

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Blood Supply

• a freely anastamosing arterial network supplies
  the ureter throughout its course
• superior segment from the renal and ovarian
  arteries
• middle segment from aortic and common iliac
  branches
• pelvic ureter by multiple vessels such as the
  uterine, vaginal, middle rectal, and vesical
  arteries
• origin of the blood supply is important when
  exposing the ureter.
• upper and middle portions blood supply comes
  from medial aspect
• pelvic ureter - derives its blood supply
  primarily from the lateral side
• The rich collateral blood supply allows the
  ureter to be freely mobilized as long as the
  longitudinal supply within the paraureteral
  adventitia is not disrupted

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OB/GYN Anatomy

• John M Fitzsimmons, MD
• Department of Radiology
• Division of Anatomy
• Colleges of Medicine
• Michigan State University