Chapter 41- Normal Anatomy and Physiology of the Female Pelvis
Interstitial portion:
Pierces uterine wall at cornua
mesovarium ligament
Posterior fold of broad ligament; encloses ovary
Fallopian Tubes length:
12 cm; blood is supplied by ovarian arteries and veins
Uterine artery has branches that perforate serosa into myometrium forming arcuate vessels which can be seen sonographically.
Anechoic tubular structures in outer third of myome
The Bony Pelvis
Consists of four bone -Two innominate (coxal) bones - Sacrum -Coccyx
Retroversion:
Entire uterus tilted posteriorly
cardinal ligament
Extend across pelvic floor laterally; firmly supports cervix
uterosacral ligament
Extend from uterine isthmus downward, along side rectum to sacrum; firmly supports cervix
suspensory ligaments
Extends from lateral aspect of ovary to pelvic sidewall
Pelvic landmarks
External Landmarks -Mons pubis -Labia majora -Labia minora -Clitoris -Urethral opening -Vestibule of vagina
Retroflexion:
Fundus and body bent backward towards cervix
round ligament
Fundus to anterior pelvic sidewalls; holds uterus forward
infundibulum
Funnel-shaped lateral tube projects beyond broad ligament to overlie ovaries; "free edge" of the funnel has fimbriae
Isthmus:
Hardest part; lies lateral to uterus
broad ligament
Lateral aspect of uterus to pelvic sidewall
Vagina....
Lateral view of pelvis - relationship of anterior and posterior fornices to the cervix and vagina.
Anteversion:
Most common position; fundus and body tipped forward toward cervix
Dextroversion or levoversion:
Normal variant in absence of pelvic masses
Internal iliac arteries: ____ extend along posterior wall to perfuse pelvic structures (bladder, uterus, vagina and rectum)
(Hypogastric)
Ovaries
-Almond shaped -Variable positions
Ovaries......
-Anterior to internal iliac artery and vein -Medial to external iliac artery and vein
Bladder BASE:
-Anterior to vagina, superior surface related to uterus
The Pelvic Cavity and Perineum.......
-Anterior: Occupied by bladder, ureters, ovaries, fallopian tubes, uterus, vagina
The Pelvic Cavity and Perineum..
-Anterolateral walls formed by hip bones and obturator internus muscles, which rim ischium and pubis
Uterine Positions
-Anteversion -Dextroversion or levoversion -Retroversion -Retroflexion
The Pelvic Cavity and Perineum....
-Area below pelvic floor is perineum
Vagina & Cervix.
-Area of vaginal lumen surrounding cervix divided into four fornices -Arterial supply from vaginal and uterine arteries; drains into internal iliac vein
Ovaries.
-Attached at posterior aspect of broad ligament by mesovarium
Ovaries.....
-Blood drained by ovarian vein into IVC on right and into renal vein on left
uterine ligaments
-Broad -Mesovarium -Mesosalpinx -Round -Cardinal -Uterosacral -Suspensory -Ovarian
Ovaries Normal Anatomy...
-Central medulla composed of connective tissue containing blood, nerves, lymphatic vessels, and some smooth muscle at region of hilum
Vagina & Cervix..
-Cervix: projects into vaginal canal -Endocervix: Cervical canal; communicates with uterine cavity by internal os; vagina by external os -Exocervix: Continuous with vagina
Ureters..
-Coarse anteriorly and medially under base of broad ligament where crossed by uterine artery
Vagina
-Collapsed muscular tube that extends from external genitalia to cervix of uterus
Ovaries Normal Anatomy
-Consist of outer layer, or cortex, which surrounds central medulla
Ovaries Normal Anatomy.
-Cortex consists primarily of follicles in varying stages of development and is covered by layer of dense connective tissue, tunica albuginea.
Uterus.
-Covered with peritoneum except anteriorly below os where peritoneum reflected onto bladder
Ureters
-Cross pelvic inlet anterior to bifurcation of common iliac arteries
Ovaries....
-Dual blood supply; receives blood from ovarian artery and uterine artery
Ovaries.......
-Ellipsoid shape with long axis oriented vertically
Ovaries...
-Fossa is bounded by external iliac vessels, ureter, obturator nerve
Uterus
-Hollow, pear-shaped organ -Divided into fundus, body, cervix -Usually anteflexed and anteverted
Ovaries Normal Anatomy.....
-Hormones responsible for producing and maintaining secondary gender characteristics, preparing uterus for implantation of fertilized ovum, development of mammary glands in female
Fallopian Tubes
-Infundibulum -Isthmus -Ampulla -Interstitial portion
endometrium
-Inner mucous membrane, glandular portion of uterine body
Cervix..
-Is a continuous ring-shaped space with posterior fornix running deeper than its anterior counterpart
True Pelvis
-Is situated inferior to caudal portion of parietal peritoneum -also considered the pelvic cavity
The Pelvic Cavity and Perineum......
-Known as pelvic diaphragm
Ovarian Ligaments.
-Laterally by suspensory (infundibulopelvic) ligament, extending from infundibulum of fallopian tube and ovary to sidewall of pelvis
Muscles of the Pelvis..
-Levator ani: Pelvic floor (diaphragm) -Coccygeus: Posterior pelvic floor (diaphragm)
Ovaries..
-Lie in ovarian fossa (also known as fossa of Waldeyer - Peter Callen)
Vagina.
-Lies posterior to urinary bladder and urethra, anterior to rectum and anus
Bladder APEX:
-Located posterior to pubic bones
Ovaries........
-Location highly variable as ligaments loosen, especially after pregnancy
The Pelvic Cavity and Perineum...
-Lower margin of pelvic cavity, pelvic floor, formed by levator ani and coccygeus muscles
Vagina...
-Measures approximately 9 cm in length; is longest along posterior wall
Uterine Size-Body of uterus::
-Medial to broad ligaments and uterine vessels -Uterine cavity is funnel-shaped in coronal plane; "slitlike" in sagittal plane
The Abdominal Wall
-Muscles extend superiorly from xyphoid process to symphysis pubis inferiorly
myometrium
-Muscular middle layer of uterus composed of thick, smooth muscle supported by connective tissue
Vagina..
-Normally directed upward and backward, forming 90-degree angle with uterine cervix
Muscles of the Pelvis....
-Obturator internus: Anterolateral pelvic sidewall
ovarian ligament
-Ovarian: Extends medially from ovary to uterine cornua
Ovarian Ligaments
-Ovaries supported medially by ovarian ligaments, originating bilaterally at cornua of uterus
Ovarian Ligaments..
-Ovary also attached to posterior aspect of broad ligament via mesovarium
Muscles of the True Pelvis
-Piriformis muscles -Obturator internus muscles -Muscles of pelvic diaphragm -Coccygeus muscles -Levator ani: 3 muscles which are -Pubococcygeus muscles -iliococcygeus muscles -puborectalis muscles
Muscles of the Pelvis...
-Piriformis: Posterolateral wall
Uterine Size-Body of uterus:
-Posterior to vesicouterine pouch and superior surface of bladder -Anterior to rectouterine pouch (of Douglas), ilium, colon
Cervix.
-Posterior vaginal wall attaches higher on cervix, and fornices are blind pockets formed by inner surface of vaginal walls and outer surface of cervix.
The Pelvic Cavity and Perineum
-Posterior wall formed by sacrum and coccyx
The Pelvic Cavity and Perineum.....
-Posterior: Occupied by rectum, colon, ileum
The Pelvic Cavity and Perineum.
-Posterolateral wall formed by piriformis and coccygeus muscles
Uterine Size
-Premenarchal: 1.0 - 3.0 cm long by 0.5-1.0 cm wide -Menarchal: 6.0 - 8.0 cm long by 3.0-5.0 cm wide -With multiparity: Increases size by 1.0-2.0 cm -Postmenopausal: 3.5 - 5.5 cm long by 2.0-3.0 cm wide
Ovaries Normal Anatomy....
-Produce reproductive cell—ovum, two known hormones: estrogen, secreted by follicles, and progesterone, secreted by corpus luteum
Cervix
-Protrudes into upper portion of vaginal canal forming four archlike recesses called fornices
Muscles of the False Pelvis
-Psoas major -Iliacus muscles -Iliacus muscle joins the psoas muscle to form the iliopsoas muscle along the sidewall of the false pelvis.
Muscles of the Pelvis
-Psoas major: Pelvic sidewall -Iliacus: Pelvic sidewall
Bladder NECK:
-Rests on upper surface of urogenital diaphragm; inferolateral surfaces relate to retropubic fat, obturator internus, levator ani muscles, pubic bone
Uterus...
-Round ligaments hold uterus in anteverted position
Ureters...
-Run anterior and lateral to upper vagina to enter posteroinferior bladder
Ureters.
-Run anterior to internal iliac arteries and posterior to the ovaries
perimetrium
-Serous outer layer of uterus; serosa
Uterus..
-Supported by levator ani muscles, cardinal ligaments, uterosacral ligaments
Ovaries Normal Anatomy..
-Tunica albuginea surrounded by single, thin layer of cells known as germinal epithelium
Vagina & Cervix
-Vagina: extends upward and backward from vulva -Upper half lies above pelvic floor -Lower half lies within perineum
Mesosalpinx liagment
Upper fold of broad ligament; encloses fallopian tube
Ampulla:
Widest part of tube where fertilization typically occurs
Blood is supplied to ____ by radial arteries in base of endometrium, where straight and spiral arteries branch off to supply the zona basalis of endometrium.
endometrium
Common iliac arteries bifurcate into ____?
external iliac and internal iliac arteries:
Layers of the uterus
perimetrium, myometrium, endometrium
Blood from ____ is shed during menses.
spiral arteries
Bony pelvis is divided into two regions
true and false -by oblique plane that passes through pelvic brim. This plane division passes from superior border of sacrum to superior margin of pubic symphysis and corresponds to iliopectineal line.