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95 terms

Organization of the Pelvis

Pelvic Wall
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False Pelvis (Greater)
Above the pelvic brim
Portion of abdomen between the iliac fossa
True Pelvis (Lesser)
What part of the pelvis lies BELOW the pelvic brim?
Borders of the True Pelvis
Pelvic Inlet: Pelvic inlet, brim and Superior pelvic aperture (P.I.S)
-Above=Public symphysis and crest
-Sides = Iliopectineal Line
-Posterior = Sacral promontory
Pelvic Outlet: Inferior pelvic aperture (P.I.I.S.C)
-Pubic symphysis
-Ischiopubic ramus
-Ischial tuberosities
-Sacrotuberous ligaments
-Coccyx
What separates the pelvis from the perineum? And forms the floor of the Pelvis?
The Pelvic Diaphragm
Where are the Pubic Tubercles and the ASIS in the anatomical position?
Located on the same vertical plane
Anterior Wall of the Pelvis
Pubic bone
Public symphysis
What are the components of the Lateral Wall of the Pelvis?
Hip bone below the pelvic inlet
Obturator internus muscle
Obturator membrane
Posterior Wall of the Pelvis
Piriformis muscle
Sacrum and coccyx
Function of the Piriformis muscle?
Laterally rotate the thigh
Pelvic Diaphragm
Levator Ani Muscle- Anteriorly
Coccygeus Muscle - Posteriorly
What structures passes through the Pelvic Diaphragm (front to back)
Urethra, Vagina and Anal canal
Is the Diaphragm complete or incomplete at the urogenital hiatus?
Incomplete so as to allow passage of urethra (m/f) and vagina (f)
Function of Pelvic Diaphragm
Supports all pelvic viscera
Involved in voluntary control of micturition and support of uterus
Male Pelvis
Which Pelvis is
Smaller angle ~45 deg
Heavier and thicker?
Female Pelvis
Which pelvis is >80 degrees (has a larger pelvic inlet and outlet) and is shallower and wider
T/F?
The Parietal Pelvic Fascia is continuous above with the fascia lining the abdominal wall
True: Eg. Transversalis fascia
T/F The Parietal Pelvic Fascia forms a looser connective tissue membrane on the pelvic surface of muscles and blends with the periosteum of the bony pelvic boundaries?
False - A RELATIVELY DENSE Membrane
Arcus Tendinous
Thickening of the obturator internus fascia and important as the origin of a large portion of the levator ani muscle
Superior Fascia of the Pelvic diaphragm
The Parietal fascia covering the pelvic surface of the pelvic diaphragm
Visceral Pelvic Fascia
Looser connective tissue investing the pelvic viscera (Uterus, vagina, bladder, rectum)
Subperitoneal Pelvic Fascia
Fatty continuation of the extraperitoneal fascia from the abdomen into the pelvis
All the ligaments formed blends medially with the visceral fascia covering the visceral organs and laterally with the parietal pelvic fascia
What are the ligaments formed from the condensations of the Subperitoneal Pelvic Fascia
Pubovesical ligaments
Lateral cervical ligaments
Uterosacral Ligament
Most important for support of the Pelvic floor (in females)?
Mackenrodt's Ligament
Blood Vessels of the Pelvis
Common Iliac Artery -> Bifurcates at the pelvic brim in front of sacroiliac joint into -> External and Internal iliac arteries.
External Iliac Artery
Continues the course of the Common Iliac artery along the pelvic brim
Internal Iliac artery
Passes downwards into the pelvis and contributes most of the its blood supply.
What are the exceptions of the Internal Iliac artery supply?
The Ovarian artery (branch of abd aorta)
Superior rectal artery (terminal branch of inferior mesenteric)
T/F Veins of the pelvis correspond closely to the arteries?
True
T/F The Common Iliac artery has branches
FALSE
T/F The rectum is a direct continuation of the sigmoid colon
TRUE
Rectum
Begins at rectosigmoid junction in front of S3 as a continuation of the sigmoid colon
T/F The rectum ends at the anorectal junction in front of the tip of the coccyx as the rectum pierces the pelvic diaphragm
TRUE
What is the lower part of the rectum?
Dilated, forming the Rectal Ampulla (latin for Flex)
T/F Ureters are retroperitoneal
True
Ureters
Descend on surface of psoas major muscles
Cross into pelvis OVER difurcation of Common Iliac arteries
Enters the urinary bladder at the superolateral angle, course obliquely through the wall app 3/4inch before opening into the bladder
What crosses over the Ureter in Males?
Ductus Deferens
What crosses over the Ureter in Females
The Uterine Artery:
Water (Ureter) runs under the bridge (Uterine artery)
Name the three sites for Kidney Stones
Junction of ureter and Renal pelvis
Where ureter crosses pelvic brim
Passage through the urinary bladder
Adult Bladder
Posterior to the pubis, rises into the abd as it fills, lifting peritoneum off inner surface of the anterior abd wall
What separates the bladder from the pubis?
The Retropubic space
The infant Bladder
Empty-lies largely above pelvic brim (an abd organ until age 8-10)
Where does the Neck of the Male Bladder rest?
On the Prostate gland - so its alittle higher in the pelvis
Where does the neck of the Female bladder rest?
On the urogenital diaphragm - so it has a lower position in the pelvis
Vagina
Fibromuscular tube extending anteroinferiorly
What are fornices?
Extensions of the vagina.
Vaginal recesses at upper end formed around the vaginal portion of the cervix
Which is LONGER - The posterior or anterior vaginal wall?
Posterior (because of angle betw vagina and cervix)
Which is DEEPER and LONGER - The anterior, posterior or lateral fornices?
Posterior (because of angle betw vagina and cervix)
What are the anterior borders/Relations of the Vagina?
Bladder - above
Urethra - Below
What separates the vagina from the anal canal?
Perineal Body:
A lot of muscles embedded here, site for episiotomy
What are the posterior borders/Relations of the Vagina?
Upper 1/3= Uterorectal pouch of Douglas
Middle 1/3 = Rectal Ampulla
Lower 1/3 = Perineal body
What is the deepest part of the Vagina?
Upper 1/3=Uterorectal pouch of Douglas
Structure of the Uterus
Fundus = Above entrance of the uterine tubes
Body = Beneath the entrance of the uterine tubes
Cervix = Narrow inferior portion
How does the cervix communicate with the body?
Through the Internal Os
How does the cervix communicate with the Vagina
External Os
Fornices
Recesses encircling the intravaginal portion of the cervix
Anterior, Posterior and Lateral
What is the lower portion of the body of the uterus adjoining the supravaginal segment of the Cerix?
Isthmus of the Uterus
Anteversion
Longitudinal axis of uterus is bent forward ~90 deg relative to the vagina.
Longitudinal axis of uterus bent forward or backward?
Forward
Anteflexion
Body of uterus is bent forward at junction of the internal Os and cervical canal
Why is the normal Uterus anteflexed?
Intrinsic to fibromuscular wall of the body and cervix
Why is the normal uterus considered to be Anteversioned?
Pull exerted on the cervix by uterosacral ligaments.
Uterine Tubes
Located on either side of uterus immediately below the fundus in the free edge of the broad ligament
What are the segments of the uterine tubes?
Infundibulum= funnel shaped lateral end - Fimbriae (fingerlike processes of the infundib), Ovarian fimbbria (attached to the ovary
Ampulla= widest part of tube and site of fertilizt
Isthmus = Narrowest part of tube closest to uterine wall
Intramural part - segment piercing the uterine wall
Where is the usual site for fertilization?
Ampulla of the uterine tube
this part of the infundibulum attaches to the ovary
Ovarian Fimbria
What is the narrowest part of the uterine tube
Isthmus
T/F The uterine tubes are functionally a muscular continuation of the Uterus
True
How can pathogenic organisms enter the body during sex?
Through vagina->cervix-->uterus-->uterine tubes
What usually follows the entry of a pathogenic organism in the body during sex?
Salpingitis
What is Salpingitis
Leakage of pus into the peritoneal cavity causing Pelvic peritonitis
What is an ectopic pregnancy?
Implantation and growth of a fertilized ovum outside the uterine cavity
Where does ectopic pregnancies usually occur?
Uterine tube
How is an ectopic pregnancy life threatening?
Eroding action of the trophoblast quickly destroys the wall of the tube and causes an effusion of a large amt of blood into the uterovesical pouch or the uterorectal pouch of Douglas
Is the broad ligament a Single or double layered fold?
Double layered extending from lateral margins of uterus to lateral pelvic walls
How is the ovary attached to the posterior layer?
By the Mesovarium
Is the ovary attached to the posterior or anterior layer of the broad ligament?
Posterior
What is the Mesosalpinx?
The part of the broad ligament forming the mesentery of the uterine tube
Mesometrium
Major part of the broad ligament, below the mesovarium and mesosalpinx
Suspensory Ligaments of the Ovary
Lateral-most part of the broad ligament which encloses the ovarian vessels, nerves and lymphatics
What structures are enclosed by the Broad ligament?
Uterine tubes (in upper free border)
Ovarian ligaments
Round ligaments
Uterine and ovarian blood vessels
Ovarian and Round Ligament
What are the derivatives of the Gubernaculum?
Ovarian ligament
Runs in the posterior lamina of the broad ligament from uterine pole of ovary to uterus just below uterotubal junction
Round Ligament
Runs in the anterior lamina of the broad ligament from pt just below uterotubal junction to labia majora via inguinal canal.
What are the chief supports of the Uterus?
Levator Ani muscles
Perineal body
Transverse cervical ligaments (Cardinal ligament, Mackenrodt's ligament)
Uterosacral ligament
Uterine Artery
Main blood supply of the Uterus
T/F The uterine artery runs in the base of the broad ligament and crosses the ureter at 90 deg near the lateral fornix of the vagina?
True
T/F The uterine artery ascends along the lateral border of the uterus within the broad ligament and ends by anastomosing with the ovarian artery?
This is true. Before ascending it also gives off descending cervical and vaginal branches
What is prolapse of the Uterus?
Downward displacement of the uterus
What usually accompanies prolapse of the Uterus?
Prolapse of the vagina
How is prolapse of the uterus caused?
Weakening of the Levator ani muscles, perineal body or ligaments supporting the uterus during childbirth or due to poor muscle tone.
When does prolapse of the uterus usually occur?
During menopause when the pelvic fascias tend to atrophy along with the pelvic organs.
T/F The ovarian ligament connects the ovary to the uterus?
True. The Ovarian ligament aka the upper part of the gubernaculum
Ovarian Fossa
Position of ovary in young nulliparous woman
What are the borders of the Ovarian Fossa?
Anterior-External Iliac vessels
Posterior - Internal iliac vessels and ureter
Why is Ovarian pain sometimes perceived on the medial side of the thigh?
Because the ovary lies close to the obturator nerves in the ovarian fossa. So inflammation of the ovary or peritenum in the ovarian fossa may affect the obturator nerve