Flashcards in The Pelvic Viscera Deck (73)
When does the rectum begin (and at which vertebra) and where does it end?
Begins at the 3rd sacral vertebra where the sigmoid colon becomes the rectum
Ends as the rectum pierces the pelvic diaphragm and becomes the anal cavity
What are the four changes as the sigmoid colon becomes the rectum?
1. Bowel loses mesentary and becomes closely applied to curvature of sacrum
2. Taenia coli broaden out and form complete outer longitudinal layer (in sigmoid colon is three separate bands)
3. Haustra disappears
4. Epiploic eppndages disappear
What is the lower part of the rectum called where it is dilated?
What artery primarily supplies the rectum?
Superior rectal artery
What part of the rectum does the middle rectal artery supply?
Lower part of rectum; this artery primarily supplies male/female reproductive organs
What is supplied by the inferior rectal artery?
Inferior rectal artery primarily supplies anal cavity rather than rectum
Which muscle of the posterior abdominal wall do the ureters pass over?
The psoas major muscle
In pelvis, the ureter is crossed over by different structures in males and females. What are those structures?
In females, ureters are crossed over by uterine artery
In males, ureters are crossed over by vas defrens
What are the 3 sites of constriction in the ureters?
1. At the junction of the ureter and renal pelvis
2. Where ureter crosses the pelvic brim
3. In passage through the urinary bladder
What spinal cord segments are visceral pain afferents of the ureters relayed?
Segments T11 - L2 (follows sympathetic innervation)
Describe general location of the urinary bladder.
Lies posterior to the pubis, rises into abdomen as it fills. Separated from pubis by the retropubis space. In males the urinary bladder rests on the prostate gland.
What general structure is on top of the urinary bladder on the superior surface of the bladder?
The peritoneum lies on top of the superior surface of the urinary bladder.
What holds the neck of the bladder in position, in males and in females?
Males: puboprostatic ligaments
Females: pubovesical ligaments
What are the 5 main internal features of the urinary bladder?
1. Rugae: mucosal folds
2. Trigone: no rugae, firmly adhered to muscular coat, near base of bladder
3. Uvula (in males): smooth eminence just above urethal orifice
4. Detrusser muscles: 3 layers of smooth muscles
5. Sphincter vesicae: thickening of circular layer of smooth muscle at neck of bladder
What is the blood supply of the urinary bladder in both males and females?
Males: Superior and inferior vesical arteries
Females: Superior vesical arteries and vaginal branches
Where does the parasympathetic innervation originate from, and where does it innervate/with what actions?
Comes from pelvic splanchnic nerves (S2 - S4)
Provides motor to the detrussor muscle
Is inhibitory to the spinchter vesicae
Where does the sympathetic innervation of the urinary bladder originate from (which spinal cord segments)?
T11 - L2
Where does the pain fibers of the urinary bladder follow back to?
Superior surface of the urinary bladder follow the T11 - L2 (same as sympathetic)
Inferior surface of the urinary bladder follow the pelvic splanchnic nerves S2 - S4 (parasympathetic innervation)
What are the fornices of the vagina?
Vaginal recesses formed at upper end/upper part of vagina. There are anterior, posterior, and lateral fornices that are all really 1 fornix.
What 3 arteries supply the vagina? What artery are they a branch of?
All 3 are branches of the anterior division of the internal iliac artery
Where does the innervation to the superior and inferior part of the vagina come from?
Superior 3/4 viscerals follow splanchnic nerves S2-S4
Inferior 1/4 somatic pain afferents via pudendal nerve
What 2 structures lie anterior to the vagina?
What 3 structures lie posterior to the vagina?
Upper 1/3: Uterorectal pouch of Douglas
Middle 1/3: Rectal ampulla
Lower 1/3: Perineal body (which separates it from anal canal)
What 3 portions make up the general structure of the uterus?
Fundus: lies above entrance of uterine tubes
Body: lies beneath entrance of uterine tubes
Cervix: narrow inferior portion
The cervical canal communicates with body through the ____ and with the vagina through the ____.
Cervical canal communicates with body through internal os and with vagina through external os.
What is the isthmus of the uterus?
It is the lower portion of the body of the uterus that joins the supravaginal segment of the cervix
What differentiates the supravaginal and intravaginal portions of the cervix?
The cervix protrudes through the uppermost anterior wall of the vagina, demarcating the supravaginal and intravaginal portions of cervix.
What are the two possible orientations of the uterus, and what causes them?
Anteversion, where logitudinal axis of uterus is bent forward 90 degress relative to vagina
- caused by uterosacral ligaments
Anteflexion, where body of uterus is bent forward at junction of internal os and cervical canal
- intrinsic to fibromuscular walls of cervix and body
What are the 4 segments of the uterine tube, starting with the one closest to the body of the uterus?
1. Intramural - segment piercing uterine wall
2. Isthmus - narrow part close to uterine wall
3. Ampulla - widest part where fertilization occurs
4. Infundibulum - funnel shaped lateral ends, with fimbriae and ovarian fimbria
What happens in ectopic pregnancy?
A fertilization ovum implants somewhere other than uterine wall, often the uterine tube. Erodes and destroys the tube and causes bleeding
What happens in pelvic inflammatory disease?
Pathogenic organisms enter vagina and cervix causing inflammation
What are the four parts of the broad ligament of the uterus?
1. Mesovarium - attaches ovary to posterior layer
2. Mesosalpinx - forms mesentery of uterine tube
3. Mesometrium - largest major part of broad ligament
4. Suspensory ligament of ovary - carries ovarian vessels/nerves/lymphatics
What 3 structures are enclosed by the broad ligaments?
1. Uterine tubes (aka fallopian tubes)
2. Ovarian ligaments
3. Round ligaments
What two ligaments are derivatives of the gubernaculum?
Ovarian ligament - runs in posterior lamina of broad ligament
Round ligament - runs in anterior lamina of broad ligament
What 3 ligaments are formed by pelvic fascia?
1. Sacrouterine (sacrocervical) ligament - cervix/upper vagina to sacrum
2. Lateral Cervical (cardinal) ligament
3. Pubovesical ligaments - connect cervix to pubic bones
What are 4 chief supports of the uterus?
1. Levator ani muscles
2. Perineal body
3. Transverse cervical ligaments
4. Sacrouterine ligaments
When is uterine prolapse most likely to occur, and what causes it?
Most likely to occur during menopause, is the downward displacement of the uterus, and may be caused by weakening of the chief supports
What artery supplies the uterus?
In which ligament does the uterine artery pass through?
Cardinal ligament (transverse cervical ligament)
Describe the crossing of the ureter and the uterine artery at the lateral fornix of the vagina.
The uterine artery crosses over the ureter at the lateral fornix of the vagina (the bridge crosses over the water)
What two branches come from the uterine artery, and what do those branches supply?
The larger superior branch (supplies body and fundus of uterus)
The smaller vaginal branch (supplies cervix and vagina)
What do branches does the superior branch of the uterine artery branch into? What do they anastomose with?
The superior branch divides into the ovarian and tubal branches, which anastomose with the ovarian and tubal branches of the ovarian artery.
What is the afferent innervation of the 3 parts of the uterus as well as the vagina?
1. Body of Uterus: afferents follow sympathetic fibers and enter at T11, T12
2. Cervix and upper vagina follow parasympathetic fibers and enter S2-S4
3. Lower vagina receives somatic innervation through pudendal nerve
What connects the ovary to the broad ligament?
Which ligament connects ovary to uterus?
The ovarian ligament
What ligament contains the blood vessels, nerves, and lymphatics of the ovaries?
The suspensory ligament (part of broad ligament)
Describe the anterior and posterior borders of the ovarian fossa (the position of ovary in young nulliparous women)
Anteriorly bordered by the external iliac artery
Posteriorly bordered by the internal iliac vessels and the ureter
Where does the obturator nerve pass through the ovarian fossa?
Obturator nerve passes along ovarian fossa between the pelvic wall and ovary
What is the sympathetic and visceral afferent pain innervation of the ovaries?
Sympathetic: T10 - T11
Visceral afferent pain fibers: follow sympathetics and enter spinal cord at T10 - T11 levels
Which node does the lymphatic drainage of the ovaries go into?
The lumbar node (para-aortic node); important for the spread of cancer
Where is the referred pain of the ovaries?
-Ovarian pain can be periumbilical (e.g. right or left iliac fossa due to inflammation)
-Ovarian pain can be on medial side of the thigh due to innervation of obturator nerve
What are the 3 portions of the male urethra?
Prostatic portion, membranous urethra, penile
What is the urethral crest of the prostatic portion of the male urethra? What are the prostatic sinuses?
Urethral Crest: midline fold of mucosa
Prostatic Sinuses: shallow depressions on each side of crest (15-20 prostatic ducts perforate here)
What is the seminal colliculus (verumonatanum) of the urethral crest? What is the prostatic utricle?
Seminal colliculus is the expanded center of the crest
Prostatic utricle is a small pouch opening at center of seminal colliculus (homolog of uterus)
What two vessels are received by the ejaculatory ducts? Where do they open into?
The ejaculatory ducts receives the ductus defrens and the seminal vesicle, and they open into the seminal colliculus
What part of the urethra pierces the urogenital diaphragm? What glands are contained here?
The membranous urethra pierces the urogenital diaphragm, and the diaphragm contains the bulbourethral glands
What do the ducts of Cowper's gland dump into?
Received by the penile portion of the urethra
What is the part responsible for mucous secretion in the penile portion of the male urethra?
Glans of Littre
What is the terminal dilation within the glans penis?
Navicular fossa (expansion at end of penis)
What portions of the male urethra is the female urethra analogus to?
The first two parts (prostatic and membranous)
What is the expansion of the ductus defrens on the posterior surface of the bladder?
What is the duct called when the seminal vesicle and the ductus defrens meet?
The ejaculatory duct, which pierces the prostate gland
Where does the ductus defrens emerge from?
The ductus epipdidymis
What arteries supply the ductus deferens?
Artery of the ductus deferens
Inferior vesical and middle rectal arteries (recall middle rectal artery supply basically all of the reproductive organs in males)
What separates the two seminal vesicles from each other on the posterior surface of the bladder?
The ampulla of the ductus defrens
What arteries supply the seminal vesicles?
Inferior vesical arteries and the middle rectal arteries
What is the apex of the prostate applied to? What is the base of the prostate applied to?
Apex is applied to the urogenital diaphragm (same place where Cowper's glands are)
Base is applied to the neck of the urinary bladder
What are the 3 zones of the prostate gland?
Central zone - surrounds ejaculatory ducts
Transitional zone - lies around central part of the prostatic urethra
Peripheral zone - surrounds central and transitional zones (except anterior region, filled by fibromuscular stroma)
Where in the prostate is the usual site of benign prostatic hypertrophy? Where is the site of carcinomas in the prostate?
Transitional zone is usual site of benign prostatic hypertrophy
Peripheral zone is usual site of carcinomas of prostate
What is the name of the transition of the peritoneum from the upper ends of the seminal vesicles to the anterior rectum in males?
What is the pouch of the peritoneum called when it passes over the bladder and runs up the anterior surface of the uterus at the level of the internal os?
Forms the utereovesical pouch
What is the name of the pouch formed by the peritoneum on the anterior surface of the rectum from the posterior surface of the uterus/posterior fornix of the vagina?
Rectouterine pouch of Douglas