Pelvis/Reproductive

While performing a hysterectomy, the resident must ligate the uterine artery. To avoid iatrogenic injury to the ureters, she must be aware that the ureter passes ___________ the artery at the level of the ______________. a) Over; cervix b) Over; fundus of uterus c) Over; pelvic brim d) Under; cervix e) Under; pelvic brim

d) Under; cervix Remember--the ureter passes under the uterine artery, in the inferior portion of the mesometrium, near the cervix! This is a very important relationship--see Netter Plate 370 for a picture.

The prostate gland: a) encircles the urethra b) is well imaged using an intravenous urogram c) is partially intraperitoneal d) contains upper, middle and lower lobes

a) Encircles the urethra The prostate gland encircles the urethra. It circles around the first part of the urethra, the prostatic urethra. This is why urinary retention is one symptom of prostatic hypertrophy--if the prostate is enlarged, it may close around the urethra, occluding this passage and preventing urine from exiting the bladder. The prostate would not be imaged using an intravenous urogram. In an intravenous urogram, a patient is given IV contrast, and radiographic images are taken as the contrast is excreted, passing through the kidneys, ureters, and bladder. Since the prostate is not part of this excretory pathway, it would not be viewed through this method. The prostate gland is completely extraperitoneal. Remember: the rectovesicular pouch, a fold of peritoneum that hangs between the bladder and rectum, is the lowest extent of the peritoneal cavity in males . But, the prostate is found on the posterior side of the bladder, below the point where the peritoneal membrane created this fold. So, it is an extraperitoneal organ. Finally, the lobes of the prostate are: anterior, posterior, lateral, and middle.

You are observing a doctor perform an abdominal hysterectomy. He notes that it is vital to protect the ureter which is found in the base of the: a) mesometrium b) mesovarium c) mesosalpinx d) round ligament of the uterus e) suspensory ligament of the ovary

a) Mesometrium The mesometrium is the part of the broad ligament of the uterus that attaches the body of the uterus to the pelvic wall. The ureters pass through the base of the mesometrium as they travel to reach the bladder. See Netter Plate 346 for a picture of this relationship. The mesovarium is the part of broad ligament that forms a shelf-like fold supporting the ovary. The suspensory ligament of the ovary, which conveys the ovarian vessels, lymphatics, and nerves to and from the ovary, constitutes the lateral part of the mesovarium of the broad ligament. The mesosalpinx is the part of broad ligament that supports the uterine tube. Finally, the round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus. It lies in the mesometrium, and it is continuous with the ovarian ligament.

Which statement is true regarding pelvic veins? a) The external iliac vein lies medial to the external iliac artery b) The external iliac veins join to form the inferior vena cava c) The inferior vena cava cannot be imaged d) Pelvic veins are usually imaged using an arteriogram

a) The external iliac veins lie medial to the external iliac artery The external iliac veins lie medial to the external iliac artery. The external iliac veins are not the veins that join to make the inferior vena cava. First, the external and internal iliac veins join to form a common iliac vein on each side. Then, the common iliacs join to form the inferior vena cava. The inferior vena cava can be imaged--it can be seen in axial CT scans or with a venogram. Veins are not imaged using an arteriogram--an arteriogram is for arteries! Instead, veins can be imaged with a venogram, a test where contrast is injected into the venous system.

Blood supply to the superior portions of the bladder typically arises from the ____________ arteries. a) Umbilical b) Middle rectal c) Obturator d) Inferior gluteal e) Uterine

a) Umbilical The umbilical artery supplies the superior part of the bladder by giving off the superior vesical arteries. In males, this artery supplies the ductus deferens via the artery of the ductus deferens. Distal to those branches, the umbilical artery is not patent, and it becomes the medial umbilical ligament. The middle rectal artery supplies blood to the middle of the rectum, while the obturator artery supplies blood to the medial thigh and hip. The inferior gluteal artery supplies blood to gluteus maximus, and the uterine artery supplies blood to the uterus.

During a hysterectomy, care must be taken in ligation of the uterine vessels because they cross the _________ superiorly. a) ureter b) round ligament of the uterus c) ovarian artery d) lumbosacral trunk e) inferior hypogastric plexus

a) Ureter The uterine vessels cross over the ureter as the ureters pass through the base of the mesometrium. Remember--the ureters must travel through the mesometrium to reach the base of the bladder. The relationship between the ureter and the uterine vessels is very important--you should remember this! The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majora and the uterus. It is found in the broad ligament, but it is superior to the ureter and the uterine vessels. The ovarian vessels are contained in the suspensory ligament of the ovary. The lumbosacral trunk is part of the ventral primary ramus of L4 united with the ventral primary ramus of L5--it contributes to the formation of the sacral plexus. The inferior hypogastric plexus lies between the pelvic viscera and the pelvic wall--it supplies sympathetic innervation to the vascular smooth muscle of pelvic vessels and parasympathetic innervation to the smooth muscles of the pelvis.

A 64-year-old woman was diagnosed as having carcinoma of the distal gastrointestinal tract. At surgery, lymph nodes from the sacral, internal iliac and inguinal lymph node groups were removed and sent to pathology for study. Only the superificial inguinal nodes contained cancerous cells. In which part of the GI tract was the tumor localized? a) cutaneous portion of anal canal b) distal rectum c) mucosal zone of anal canal d) pectinate line of anal canal e) proximal rectum

a) cutaneous portion of the anal canal The pectinate line is more than the line where the mucosal lining of the anal canal changes to skin. It is also a key dividing point for the flow of lymph in the anal canal. Above the pectinate line, lymph flows to the inferior mesenteric and internal iliac lymph nodes. Below the pectinate line, lymph flows to the superficial inguinal lymph nodes. So, the pathology report tells you that the tumor must be somewhere below the pectinate line since the superficial inguinal lymph nodes are the only nodes involved. The only answer representing a tumor below the pectinate line is A, the cutaneous portion of the anal canal. The proximal and distal rectum represents a space far above the pectinate line, and the mucosal zone of the anal canal is, by definition, above the pectinate line. At the pectinate line itself, lymph should be flowing to all the sets of nodes, and it would be unlikely that a tumor at the pectinate line would involve only the superficial inguinal lymph nodes.

After agreeing to have no more children, a man and his wife decided he should have a vasectomy. What structure would then be surgically ligated? a) Ductus deferens b) Ejaculatory duct c) Epididymis d) Fossa navicularis e) Seminal vesicle

a) ductus deferens In a vasectomy, the ductus deferens is ligated or excised. This means that the fluid that is then ejaculated from the seminal vesicles, prostate, and bulbourethral glands has no sperm. The sperm simply degenerate in the epididymis and the proximal ductus deferens. It would not be a good idea to ligate the ejaculatory duct or the seminal vesicle because that might compromise the patient's ability to ejaculate. Just remember, another name for the ductus deferens is the vas deferens, so it make sense that the procedure to ligate this structure is called a vasectomy.

Which structure is NOT found within the true pelvis? a) Femoral nerve b) Hypogastric nerve c) Internal pudendal artery d) Obturator artery e) Pelvic splanchnic nerves

a) femoral nerve To answer this question, you need to understand what the true pelvis is. The true pelvis is the area beneath the pelvic brim (pelvic inlet), where the pelvic viscera are located. The false pelvis is the area above the pelvic brim, bounded by the iliac blades. Now, you just need to think about the structures listed and determine which ones are in which location. The femoral nerve is the structure that is not in the true pelvis. After coming off the lumbar plexus with contributions from L2, 3, and 4, the femoral nerve runs along the border between the psoas major muscle and the iliacus to travel into the lower limb. It never descends below the pelvic brim, so it is not in the true pelvis. Hypogastric nerves connect the superior and inferior hypogastric plexuses. Since the inferior hypogastric plexus is lying between the pelvic viscera and the pelvis wall, in the true pelvis, the hypogastric nerves should also be in the true pelvis. The internal pudendal artery is a branch of the anterior division of the internal iliac artery. It lies in the true pelvis and supplies blood to the perineum. The obturator artery is a branch of the anterior internal iliac artery or, if it is the aberrant obturator, the inferior epigastric artery. It is in the true pelvis, and exits the pelvis through the obturator foramen. The pelvic splanchnic nerves represent the sacral portion of the craniosacral outflow (parasympathetic) of the autonomic nervous system. They come from the ventral rami of the second, third, and fourth sacral nerves. So, that puts them in the true pelvis, too.

Which of the following is considered a part of the broad ligament? a) Mesovarium b) Ovarian ligament c) Round ligament of the uterus d) Suspensory Ligament of the ovary e) Uterosacral ligament

a) mesovarium The mesovarium, mesometrium, and mesosalpinx are the three peritoneal sections that create the broad ligament. The mesosalpinx covers the uterine tube and hangs below it to meet with the mesovarium. The mesovarium covers the ovary and ovarian ligament. It extends posteriorly from the mesosalpinx like a shelf. The mesometrium makes up the rest of the broad ligament. The ovarian ligament is located in the broad ligament but is not part of the broad ligament. It is a round cord that attaches the ovary to the uterus just below the point where the uterine tube enters the uterus. The round ligament of the uterus reaches the lateral surface of the uterus below the uterine tube. It is continuous with the ovarian ligament and it holds the fundus of the uterus forward. The suspensory ligaments of the ovary are peritoneal folds that cover the ovarian neurovascular supply as these vessels pass over the pelvic brim to reach the ovary. Finally, the uterosacral ligament connects the isthmus of the uterus to the sacrum. It is important for the support of the uterus, and it is found in the rectouterine fold.

Which structure is outlined with contrast on a CT using intraperitoneal contrast material? a) Ovary b) Prostate c) Rectum d) Seminal Vesicles e) Vagina

a) ovary The ovary is entirely covered by a layer of peritoneum called the mesovarium. The mesovarium, along with the mesometrium and the mesosalpinx, creates the broad ligament. Because the ovary is completly encased in peritoneum, it would be outlined on a CT with intraperitoneal contrast material. The prostate, seminal vesicles and vagina are located below the rectovesicular pouch or rectouterine/vesicouterine pouches. So, they are not associated with the peritoneal cavity and would not be seen on the CT scan. Although peritoneum drapes over the rectum, forming the rectovesicular fold in males and the rectouterine fold in females, the rectum would not be clearly outlined by the intraperitoneal contrast since it is not covered by peritoneum on all sides.

The vestibular bulbs/bulb of the corpus spongiosum are firmly attached to the: a) Perineal membrane b) Superior pubic rami c) Ischiopubic rami d) Pubic symphysis e) Ischial tuberosities

a) perineal membrane The bulbs of the vestibule/bulb of the corpus spongiosum are pieces of erectile tissue that attach to the perineal membrane. They are covered by the bulbospongiosis muscle. The ischiopubic rami, pubic symphysis, and ischial tuberosities are bony structures important for defining the boundaries of the perineum. The crura of the corpora cavernosa attach to the ischiopubic rami and the perineal membrane.

Benign hyperplasia (excessive growth of cells) of which part of the male reproductive system would be most likely to interfere with the passage of urine? a) Periurethral Zone of the Prostate b) Central Zone of the Prostate c) Peripheral Zone of the Prostate d) Ejaculatory Duct e) Seminal Vesicle

a) periurethral zone of the prostate Remember that the prostatic urethra travels through the prostate gland. So, if the periurethral zone of the prostate hypertrophied, the nearby prostatic urethra would be occluded. The central and peripheral zones of the prostate are not as close to the urethra. If they enlarged, they would not restrict the flow of urine quite as much. The ejaculatory duct is the duct formed once the ductus deferens joins with the duct of the seminal vesicle. It passes through the prostate gland, but its enlargement would have no effect on the prostate or the urethra. Finally, the seminal vesicle is a sac on the posterior surface of the bladder which is superior to the prostate gland. It produces seminal fluid, and changes in the seminal vesicle should not alter the flow of urine.

Which skeletal feature would you consider to be most characteristic of the female pelvis? a) Subpubic angle of 90 degrees or greater b) Marked anterior curvature of the sacrum c) Tendency to vertical orientation of the iliac bones d) Prominent medial projection of the ischial spines

a) subpubic angle of 90 degrees or greater There are four major differences between the male and female pelvis. First, the subpubic angle and pubic arch are greater in the female pelvis than in the male pelvis. This is why A is correct-- females often have a subpubic angle of 90 degrees or greater. A second difference between the female and male pelvis is that the pelvis inlet for females is rounded, while for males it is heart shaped. Third, the pelvic outlet for females is larger than in males. Finally, the female pelvis has iliac wings that are more flared than in males.

Structures within the lower gastrointestinal tract specialized for physical support of fecal material are the: a) Transverse rectal folds b) Circular folds c) Anal valves d) Anal columns

a) transverse rectal folds There are usually three transverse rectal folds in the lower rectum. These are specializations of the circular layer of musculature that are designed to support fecal mass. Although circular folds is somewhat descriptive of the transverse rectal folds, this is not the best answer. Anal columns are longitudinal folds of mucosa over rectal vessels. They are found on the inner wall of the anal canal. Anal valves are the folds of mucosa that join the anal columns at their inferior ends.

During a hysterectomy and an oophorectomy, the uterine and ovarian vessels must be ligated. These vessels can be found in which ligaments? a) Broad and ovarian b) Broad and suspensory c) Round and ovarian d) Round and suspensory e) Suspensory and ovarian

b) Broad and suspensory The uterine vessels are found in the inferior portion of the broad ligament, while the ovarian vessels are found in the suspensory ligaments of the ovaries. The suspensory ligaments of the ovaries are peritoneal folds covering ovarian arteries, veins, nerves, and lymphatics as the structures pass over the pelvic brim to reach the ovary. The ovarian ligament proper is a round cord which attaches the ovary to the uterus, just below the entrance of the uterine tube into the uterus. The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus--it traverses the inguinal canal and it is found in the broad ligament.

During a vaginal delivery, a surgeon performed median episiotomy in which he cut too far (i.e., through the perineal body into the structure immediately posterior). Which perineal structure did he cut? a) Bulbospongiosis muscle b) External anal sphincter muscle c) Ischiocavernosis muscle d) Sacrospinous ligament e) Sphincter urethrae

b) External anal sphincter muscle An episiotomy is an incision made in the perineum to enlarge the distal end of the birth canal and to prevent serious damage to the perineal structures. This procedure is often performed when there is a risk of tearing the birth canal due to a breech or forceps delivery. When performing a median episiotomy, a cut is made immediately posterior to the vagina, through the perineal body. If this cut went too far, the physician might cut through the external anal sphincter or the rectum. So, external anal sphincter is the correct answer. It's important to remember that episiotomies are often made in the posterolateral direction, not on the midline. If the incision tears further during the delivery, a median incision is more likely than a posterolateral incision to extend posteriorly through the external anal sphincter, and the rectum. Consequently, a posterolateral incision is considered safer by some. The bulbospongiosus muscle, ischiocavernosus muscle, and sphincter urethrae are anterior to the area that is cut during an episiotomy. The sacrospinous ligament extends from the sacrum to the ischial spine--it is deep to the perineum and should not be involved with this procedure.

What bony landmark on the lateral pelvic wall may be used as a reference for localizing female pelvic anatomy or pain phenomena? a) Coccyx b) Ischial spine c) Ischial tuberosity d) Obturator canal e) Pectineal line

b) Ischial spine The ischial spine is the only answer choice on the lateral pelvic wall. It arises just superior to the lesser sciatic notch and serves as the site of attachment of the sacrospinous ligament. The coccyx is the most inferior part of the vertebral column, resulting from the fusion of the four coccygeal vertebrae. It articulates with the sacrum, which means that it is associated with the posterior wall of the pelvis. The ischial tuberosity protrudes posteroinferiorly, not laterally, from the body of the ischium. This is where weight rests when the body is in the sitting postion. The ischial tuberosity also serves as the site of attachment for the sacrotuberous ligament. The obturator canal is the space in the obturator foramen that is not covered with obturator membrane. It transmits the obturator nerve and vessels, and it is on the anterior, not lateral, side of the pelvis. Finally, the pectineal line is the ridge on the pubis that creates the anterior border of the pelvic inlet and is an important landmark of the inguinal region.

After giving birth, a patient complains of dribbling of urine while coughing, sneezing, or laughing. Which muscle was most likely damaged during the vaginal delivery? a) Coccygeus b) Levator ani c) Obturator internus d) Piriformis e) Transverse perineal

b) Levator ani Urinary stress incontinence happens when the bladder can't handle increased compression during exercise, coughing, or sneezing. This form of incontinence is the result of relaxation of the pelvic muscles and displacement of the urethrovesiculal junction. Remember--levator ani is the major pelvic muscle which elevates the pelvic floor. So, if this muscle became injured during a vaginal birth, a woman might experience urinary incontinence. Coccygeus is a smaller muscle found posterior to levator ani. It also elevates the pelvic floor, but it is not as important as levator ani. So, injury to coccygeus alone would not cause incontinence. Obturator internis is a muscle which leaves the pelvis through the lesser sciatic foramen and inserts on the greater trochanter of the femur; it laterally rotates and abducts the thigh. Piriformis is a muscle that leaves the pelvis through the greater sciatic foramen and inserts on the greater trochanter; it also allows for lateral rotation and abduction of the thigh. The transverse perineal muscle is a muscle of the perineum-- it fixes and stabilizes the perineal body/central tendinous point.

The sacral outflow of the parasympathetic (craniosacral) system enters the pelvic plexus via: a) Hypogastric nerves b) Pelvic splanchnic nerves c) Pudendal nerves d) Sacral splanchnic nerves

b) Pelvic splanchnic nerves Pelvic splanchnic nerves come from the anterior branches of S2 through S4. These are parasympathetic nerves, which send parasympathetic neurons to the hypogastric plexus, and therefore the pelvic viscera and distal colon. Hypogastric nerves are from the superior hypogastric plexus. These nerves transmit sympathetic neurons to the hypogastric plexus, and therefore the pelvic viscera. The pudendal nerve is a branch of the sacral plexus. It provides motor innervation to the muscles of the perineum, and it is the primary sensory innervation to the genitalia. Sacral splanchnic nerves are from the second and/or third ganglia of the sacral sympathetic trunk. These provide a secondary way for sympathetic neurons to reach the hypogastric plexus, and therefore the pelvic viscera.

A female patient comes to your office with lower abdominal pain. She missed her last menses and her pregnancy test is positive. Ultrasound imaging reveals a cyst-like structure in the right uterine tube which you feel may be a tubal pregnancy. In order to confirm your diagnosis and to remove the tubal embryo, you can gain access to the patient's lower pelvic cavity by passing a culdoscope through the vagina and the: a) vesicouterine pouch b) posterior fornix c) cervix d) isthmus e) ampulla

b) Posterior fornix In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity and remove the embryo. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder. The cervix is the inferior end of the uterus which connects the uterus to the vagina. The isthmus and ampulla are parts of the uterine tube--the isthmus is the constricted part of the uterine tube nearest the uterus, and the ampulla is the dilated region that connects the infundibulum with the isthmus.

In a CT scan of the pelvis, the uterus is located: a) posterior to the bladder and rectum b) posterior to the bladder and anterior to the rectum c) anterior to the bladder and rectum d) anterior to the bladder and posterior to the rectum

b) Posterior to the bladder and anterior to the rectum In the female pelvis, the bladder is the most anterior organ; the uterus is posterior to the bladder, and the rectum is posterior to the bladder and uterus. See Netter Plate 337 for a picture.

During a vasectomy, the ductus deferens is ligated in the superior part of the scrotum. Two months following this sterilization procedure, the subsequent ejaculate contains: a) Prostatic fluid only b) Seminal fluid and prostatic fluid c) Sperm only d) Sperm and seminal fluid e) Sperm, seminal fluid, and prostatic fluid

b) Seminal fluid and prostatic fluid The ductus deferens carries sperm from the tail of the epididymis to the ejaculatory duct. When this cord is ligated, sperm cannot enter the ejaculatory duct, so there will be no sperm in the subsequent ejaculate. The seminal vesicles and prostate also contribute fluid to the ejaculate. However, ligating the ductus deferens will not interrupt the path of seminal fluid or prostatic fluid. So, the ejaculate will still contain both of these fluids.

Which pair of structures does NOT differentiate from comparable embryonic structures in the male and female? a) Bulb of corpus spongeosum and vestibular bulb b) Shaft of penis and labia majora c) Glans of penis and glans of clitoris d) Crus of corpus cavernosum penis and crus of corpus cavernosum clitoris

b) Shaft of penis and labia majora The shaft of the penis is an analog of the shaft of the clitoris, while the labia majora is derived from the same embryonic structures as the scrotum. The other three answer choices list structures that come from comparable embryonic structures in the male and female. See Netter Plate 389 for a picture of the homologous structures in males and females!

The male pelvis tends to differ from the female pelvis in that the male pelvis often has a: a) larger pelvic inlet b) smaller subpubic angle c) straighter sacral curvature d) larger pelvic outlet e) rounder pelvic inlet

b) Smaller subpubic angle There are four major differences between the male and female pelvis. First, the subpubic angle and pubic arch are greater in the female pelvis than in the male pelvis. This is why B is correct-- the male pelvis has a smaller subpubic angle than the female pelvis. A second difference between the female and male pelvis is that the pelvic inlet for females is rounded, while for males it is heart shaped. Third, the pelvic outlet for females is larger than in males. Finally, the female pelvis has iliac wings that are more flared than in males.

Under normal conditions, fertilization occurs in which part of the female reproductive tract? a) Infundibulum of the Uterine Tube b) Ampulla of the Uterine Tube c) Isthmus of the Uterine Tube d) Uterine Lumen e) Cervical Canal

b) ampulla of the uterine tube Fertilization normally takes place in the ampulla of the uterine tube. This is the middle segment of the uterine tube, and it is the longest and widest segment. The infundibulum is the funnel-shaped distal end of the uterine tube, and the isthmus is the narrowest part of the uterine tube which connects directly to the uterus. The uterine lumen is the site of implantation, not fertilization. Finally, the cervical canal is the pathway out of the uterus at its inferior end-- it would not be an appropriate site for fertilization or implantation.

Which of the following does not conduct spermatozoa? a) Ampulla of the ductus deferens b) Duct of the seminal vesicle c) Epididymis d) Prostatic Urethra

b) duct of the seminal vesicle The duct of the seminal vesicle carries seminal fluid, a basic fluid containing fructose. The contents of the seminal fluid buffers the acid in the vagina and provides nutrients for sperm. The duct of the seminal vesicle joins with the ampulla of the ductus deferens (which is carying sperm) to form the ejaculatory duct. This is the first place where seminal fluid mixes with sperm. Sperm is first formed in the seminiferous tubules. They then travel from the head to the tail of the epididymis, through the ductus deferens, into the ejaculatory duct where they mix with seminal fluid, into the prostatic urethra, through the rest of the urethra, and then out the penis. So, all of the other answer choices are places that are important for the passage of sperm.

A structure which is homologous to the male scrotum: a) Labia minora b) Labia majora c) Glans d) Shaft of corpus cavernosum

b) labia majora The labia majora and scrotum are homologous structures. The labia minora is the female counterpart of the pentscrotal raphe. The glans of the clitoris and glans of the penis are homologous structures. Finally, the shaft of the corpus cavernosum in the female is the shaft of the clitoris, which is homologous to the shaft of the penis.

An intrahepatic blockage of the portal venous outflow may cause intestinal blood to drain via portal-systemic anastomoses into the: a) Superior gluteal vein b) Middle rectal vein c) Splenic vein d) Renal vein e) Inferior phrenic vein

b) middle rectal vein There are four portal-caval anastomoses in the body. First, between the superior rectal veins in the portal system and the middle and inferior rectal veins in the caval system. Second, between the esophageal veins that go to the left gastric vein (portal) and the esophageal veins that go to the azygos system (caval). Third, between the paraumbilical veins of the portal system and the veins of the anterior abdominal wall that drain into the inferior vena cava. Fourth, between the colic veins of the portal system and the retroperitoneal veins of the caval system. So middle rectal is the right answer. The superior gluteal vein, renal vein, and inferior phrenic vein are all part of the caval system; the splenic vein is part of the portal system.

The part of the uterine wall which is not shed during menstruation is the: a) Endometrium b) Myometrium c) Mesometrium d) Cervical mucosa e) Rugae

b) myometrium This question is phrased in a slightly tricky way, so it's important to break it down before looking at the answers. There are two things to think about here. First, you need to decide if a structure is part of the uterus. If it is part of the uterus, then you need to decide if it is shed during menstruation. The correct answer will be a structure that is part of the uterus but is not shed during menstruation. Answers about structures that are not shed during menstruation because they are not part of the uterine wall are incorrect. The myometrium is our correct answer. It is the middle muscular component of the uterine wall and it is not shed during menstruation. The endometrium is the inner mucosal coat of the uterus. It exhibits many characteristic changes during the menstrual cycle and all but its stratum basalis is shed during menstruation. The mesometrium is the mesentary of the uterus which forms the major part of the broad ligament of the uterus. It is not even part of the uterine wall, so it's not the answer to look for. Cervical mucosa lines the cervix, which is the inferior portion of the uterus. This mucosa is shed during menstruation. Finally, the uterus does not have rugae - rugae are the folds found in the lining of the vagina (and stomach).

The pelvic splanchnic nerves primarily carry ____________ to the _____________ plexus. a) Preganglionic parasympathetics--superior hypogastric b) Preganglionic parasympathetics--inferior hypogastric c) Postganglionic parasympathetics--superior hypogastric d) Postganglionic sympathetics--superior hypogastric e) Postganglionic sympathetics--superior hypogastric

b) preganglionic parasympathetics--inferior hypogastric Although all the other splanchnic nerves carry sympathetic fibers, the pelvic splanchnic nerves transmit preganglionic parasympathetic fibers from S2, 3, and 4. These fibers are carried to the inferior hypogastric plexus. The parasympathetic fibers from the inferior hypogastric plexus supply the smooth muscle of the pelvic viscera, while the sympathetic fibers from the inferior hypogastric plexus supply vascular smooth muscle of vessels supplying the pelvic viscera. The superior hypogastric plexus is a continuation of the intermesenteric plexus--it contributes sympathetic fibers to the inferior hypogastric plexus through hypogastric nerves.

During childbirth a bilateral pudendal nerve block may be performed to provide anesthesia to the majority of the perineum and the lower one fourth of the vagina. To do this an anesthetic agent is injected near the pudendal nerve as it passes from the pelvic cavity to the perineum. The physician inserts a finger into the vagina and presses laterally to palpate what landmark? a) Arcus tendineus levator ani b) Coccyx c) Ischial spine d) Lateral fornix e) Obturator foramen

c) Ischial spine When performing a transvaginal pudendal nerve block, the ischial spine is palpated through the wall of the vagina and the needle is then passed through the vaginal mucous membrane toward the ischial spine. Eventually, the needle pierces the sacrospinous ligament, at which point the pudendal nerve is bathed with anesthetic. Remember--the pudendal nerve is within the pudendal canal, and it wraps around the ischial spine before it delivers its branches. So, administering the nerve block at the ischial spine allows a physician to anesthetize all the branches of the pudendal nerve. This is a very important landmark that you want to remember! Also remember--the pudendal nerve block does not need to be administered transvaginally. In a perineal pudendal nerve block, the ischial tuberosity is palpated through the buttock and the needle is inserted into the pudendal canal about one inch deep medial to the ischial tuberosity. The anesthetic can then be injected to bathe pudendal nerve. In this case, a different anatomical landmark, the ischial tuberosity, is used to deliver the nerve block Arcus tendineus levator ani is the origin for levator ani. It is a specialization of the fascia of obturator internus which runs from the spine of the ischium to the superior pubic ramus. The coccyx is the most inferior portion of the vertebral column--it is found on the posterior wall of the pelvis. The lateral fornix of the vagina is the space found lateral to the cervix as it protrudes into the vagina. The obturator foramen is a large foramen on the anterior side of the pelvis, formed by the pubic and ischial rami. It is a site of attachment for obturator externus and internus. None of these structures are appropriate landmarks to use when performing a pudendal nerve block.

In a patient with rectal cancer located in the wall of the ampulla, you find that the cancer has spread to the muscle immediately lateral to the ampulla. This muscle is the: a) Piriformus b) Obturator internus c) Levator ani d) Sphincter urethrae e) Bulbospongeosis

c) Levator ani The levator ani is the muscle immediately lateral to the ampulla of the rectum, so this is where the cancer would have spread. This muscle is important for elevating the pelvic floor. The obturator internus and piriformis muscles are lateral and posterior to the rectum--they would not be affected by the cancer. The sphincter urethrae encircles and compresses the urethra. Bulbospongeosus is a muscle in the perineum which compresses the bulb of the penis and the spongy urethra in men and compresses the vestibular bulb and constricts the vaginal orifice in women.

After giving birth, a patient complains of urinary stress incontinence characterized by dribbling of urine with an increase in intra-abdominal pressure. Her physician suspects injury to the pelvic floor during delivery which may have altered the position of the neck of bladder and the urethra. Which muscle was most likely damaged during the vaginal delivery? a) Bulbospongiosus b) Coccygeus c) Levator ani d) Obturator internus e) Piriformis

c) Levator ani Urinary stress incontinence happens when the bladder can't handle increased compression during exercise, coughing, or sneezing. This form of incontinence is the result of relaxation of the pelvic muscles and displacement of the urethrovesiculal junction. Remember--levator ani is the major pelvic muscle which elevates the pelvic floor. So, if this muscle became injured during a vaginal birth, a woman might experience urinary incontinence. The bulbospongiosus muscle is found in the perineum; it compresses the vestibular bulb and constricts the vaginal orifice. Coccygeus is a smaller muscle found posterior to levator ani. It also elevates the pelvic floor, but it is not as important as levator ani. So, injury to coccygeus alone would not cause incontinence. Obturator internis is a muscle which leaves the pelvis through the lesser sciatic foramen and inserts on the greater trochanter of the femur; it laterally rotates and abducts the thigh. Finally, piriformis is a muscle that leaves the pelvis through the greater sciatic foramen and inserts on the greater trochanter; it also allows for lateral rotation and abduction of the thigh.

The part of the broad ligament giving attachment and support to the uterine tube is the: a) mesometrium b) mesovarium c) mesosalpinx d) round ligament

c) Mesosalpinx The mesosalpinx is the part of broad ligament that supports the uterine tube. The mesosalpinx extends inferiorly to meet the root of the mesovarium; it attaches the uterine tube to the mesometrium. The mesometrium is the part of the broad ligament below the junction of the mesosalpinx and the mesovarium; it attaches the body of the uterus to the pelvic wall. The mesovarium is the part of broad ligament that forms a shelf-like fold supporting the ovary--it attaches the ovary to the mesometrium and mesosalpinx. The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus. It is found in the broad ligament, and it traverses the inguinal canal.

The arcus tendineus levator ani is a thickening of fascia of the: a) Coccygeus b) Obturator externus c) Obturator internus d) Piriformis

c) Obturator internus The fascia of obturator internus has two specializations. First, there is a strong band on the medial edge of obturator internus that stretches between the spine of the ischium and the superior pubic ramus. This is the arcus tendineus levator ani, which gives origin to the levator ani muscles. The other specialization is the obturator membrane, which nearly covers the entire obturator foramen, only leaving space for the obturator nerves and vessels to exit. Coccygeus is a muscle that elevates the pelvic diaphragm--it is found posterior to levator ani. Obturator externus is not found it the pelvis--it takes origin from the external surface of the obturator membrane and inserts on the femur. It is an important muscle for laterally rotating the thigh. The piriformis muscle takes origin from the anterior surfaces of S2 to S4, both between and lateral to the sacral foramina. It exits the pelvis via the greater sciatic foramen, inserting on the greater trochanter of the femur in order to rotate the thigh laterally.

A female patient is found to have an ectopic (tubal) pregnancy (embryo develops in the uterine tube). In order to gain access to the peritoneal cavity endoscopically to remove the embryo, the instrument can be passed into the vagina and through the: a) anterior fornix b) cervix c) posterior fornix d) retropubic space e) vesicouterine pouch

c) Posterior fornix In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity and remove the embryo. Take a look at Netter Plate 337 for a picture of this relationship. Entering the anterior fornix of the vagina would not allow a surgeon to enter the peritoneal cavity. The cervix is the inferior portion of the uterus which connects the uterus to the vagina--passing through the cervix would allow the surgeon to enter the uterus, but not the peritoneal cavity. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder.

A female patient is found to have an ectopic (tubal) pregnancy. In order to gain access to the peritoneal cavity endoscopically to remove the tubal embryo, the instrument can be passed through the posterior fornix of the vagina piercing into the: a) external os b) internal os c) rectouterine pouch d) rectovesical pouch e) vesicouterine pouch

c) Rectouterine pouch In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity to remove the embryo. Take a look at Netter Plate 337 for a picture of this relationship. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder. The rectovesicular pouch is only found in males--it is a peritoneal fold reflecting from the rectum to the posterior wall of the bladder. The external os of the cervix is the part of the cervix between the vagina and the cervical canal; the internal os of the cervix is the part of the cervix between the uterus and the cervical canal. See Netter Plate 346 for a picture of these osses.

An elderly patient notices red blood in his stool. As part of his examination, you insert a proctoscope (sigmoidoscope) through his anal canal. As you pass the scope superiorly through the rectum, the most prominent features to be seen are: a) longitudinal muscle bands b) tenia coli c) transverse rectal folds d) rectovesical pouches e) haustra

c) Transverse rectal folds The rectum features three transverse rectal folds--these folds would be the most prominent features that you would see in the interior of the rectum if you were using a proctoscope. The tenia coli are the three bands of longitudinal muscle seen on the surface of the colon--the pattern of the teniae coli changes as the transition from sigmoid colon to rectum occurs. The sigmoid colon, like the rest of the colon, has three longitudinal muscular bands. These coalesce into two bands, anterior and posterior, on the rectum. However, none of these longitudinal muscle layers would be visible from the interior of the rectum. The rectovesical pouch is a peritoneal fold reflecting from the rectum to the posterior wall of the bladder in the male. Remember--females do not have the rectovesicular pouch. Instead, they have the vesicouterine and rectouterine pouches. Finally, the haustra are multiple pouches in the wall of the large intestine--they are not found in the rectum.

The expanded region of the lower rectum, where fecal matter is retained, is known as the: a) Anal columns b) Anal sinuses c) Ampulla d) Transverse folds

c) ampulla The ampulla is an expanded part of the lower rectum that stores feces. The transverse rectal folds are three folds in the ampulla which help to support fecal mass, but they are not the same as the actual region that stores the feces. Anal columns are longitudinal folds of mucosa over rectal vessels. They are found on the inner wall of the anal canal. Anal valves are folds of mucosa that join the anal columns at their inferior ends and create spaces between the wall and the valves known as anal sinuses.

A 27-year-old woman is examined by her gynecologist. Upon rectal examination, a firm structure, directly in front of the rectum in the midline, is palpated through the anterior wall of the rectum. This structure is the: a) bladder b) body of uterus c) cervix of uterus d) pubic symphysis e) vagina

c) cervix of the uterus The cervix of the uterus is anterior to the rectum. Since the cervix is the inferior part of the uterus that is protruding into the vagina, it should feel like a firm structure upon palpation. The bladder is the most anterior organ in the pelvis, in front of the uterus and rectum. So, the bladder would not be directly in front of the anterior wall of the rectum. The body of the uterus lies upon the bladder, so it is too far in front of the anterior rectal wall to be palpated. The pubic symphysis is the joint connecting the two pubic bones. It forms the anterior boundary of the pelvis, and would be too far forward to palpate through the rectum. Although the vagina is directly anterior to the rectum, it would not feel like a distinct and firm structure upon palpation.

The artery which supplies blood to the major erectile body in both the male and female is the: a) Artery of the bulb b) Dorsal artery of the penis/clitoris c) Deep artery of the penis/clitoris d) Posterior labial/scrotal artery e) Superficial external pudendal artery

c) deep artery of the penis/clitoris The deep artery supplies the corpus cavernosum of the penis/clitoris, which is the major erectile body. It is one of the two terminal branches of the internal pudendal artery, with the other one being the dorsal artery of the penis/clitoris. This artery supplies superficial structures. The artery of the bulb supplies blood to the bulb of the penis and the bulb of the vestibule. Although the bulbs are erectile tissue, the corpus cavernosum is the main erectile body. The posterior labial/scrotal artery supplies exactly what you would guess--the posterior labia or scrotum. It is a branch of the perineal artery. Finally, the superficial external pudendal artery supplies the skin and superficial fascia of the upper medial thigh, as well as the skin of the pubic region. It is a superficial branch of the femoral artery.

During the course of surgery for benign prostatic hypertrophy (benign enlargement of the prostate tissue which occludes the prostatic urethra) an electrical cutting device is inserted into the penile, then prostatic urethra, to remove the hypertrophic tissue. The posterior wall of the prostatic urethra is by necessity removed as well. Which part of the male seminal tract may also be partially removed? a) duct of seminal vesicle b) ductus deferens c) ejaculatory duct d) fossa navicularis e) seminiferous tubule

c) ejaculatory duct The ejaculatory duct travels through the prostate and opens into the prostatic urethra. So, it is likely that this duct might get removed or damaged during the surgery. The duct of the seminal vesicle and the ductus deferens are the two ducts that join to make the ejaculatory duct. They both lie on the posterior surface of the bladder and would not be interrupted by the surgery. The fossa navicularis is a dilation in the penile urethra. It would not be harmed by surgery in the prostatic urethra. Finally, the seminferous tubules are the tubules in the testes where sperm are formed.

The extension of the vaginal lumen around the intravaginal part of the uterine cervix is the: a) Cervical canal b) Uterine lumen c) Fornix d) Rectouterine Pouch e) Uterovesical Pouch

c) fornix The cervix is the inferior end of the uterus that projects into the vagina. This means that the vagina comes up and wraps around the cervix, creating the vaginal fornix. There are multiple fornices at the top of the vagina: anterior, posterior, and lateral. The cervical canal is the passageway through the cervix to the vagina. The uterine lumen is the hollow center of the uterus. The rectouterine and uterovesicular pouches are two peritoneal folds found in the pelvic cavity. The rectouterine pouch is a peritoneal fold extending across the floor of the pelvic cavity from the sacrum (beside the rectum) to the uterus. The uterovesicular pouch is a peritoneal fold extending from the uterus to the bladder.

Lymphatic drainage of the terminal portion of the gastrointestinal tract may flow initially into either the superficial inguinal nodes or the pararectal nodes, depending upon whether the lymph is formed above or below the: a) Anorectal Junction b) Muscular Sling of the Puborectalis Muscle c) Pectinate Line d) White Line e) Cutaneous Zone

c) pectinate line The pectinate line is the place where the lining of the anal canal changes from skin to mucosa. It is also a landmark that divides the lymphatic drainage, vascular supply, and innervation of the anal canal. Lymph coming from structures above the pectinate line drains to the inferior mesenteric lymph nodes or the internal iliac nodes. Lymph from structures below the pectinate line travels to the superficial inguinal lymph nodes. As far as vasculature and nerves go... Superior to the pectinate line, arterial blood comes from the superior rectal artery and drains to the portal system through the superior rectal veins. This area is innervated by the inferior hypogastric plexus (autonomic innervation). Inferior to the pectinate line, blood comes from the inferior rectal arteries and is drained into the caval system. Innervation here comes from the inferior rectal nerves (somatic innervation). The anorectal junction is the point where the rectal ampulla narrows due to a U-shaped sling created by the puborectalis muscle. This area is superior to the pectinate line. The white line is a transitional area inferior to the pectinate line that represents some subtle changes as the mucosal lining becomes "regular" skin. Finally, the cutaneous zone is the area of skin at the very end of the rectum.

Preganglionic parasympathetic nerve fibers within the pelvic (inferior hypogastric) plexus arise from S2, 3, 4 and enter the plexus via: a) gray rami communicantes b) hypogastric nerves c) pelvic splanchnic nerves d) sacral splanchnic nerves e) white rami communicantes

c) pelvic splanchnic nerves Pelvic splanchnic nerves carry parasympathetic fibers from the lateral horn of the spinal cord at the S2, 3, and 4 levels. They can be seen coming off of the ventral primary rami of S2, 3, and 4 and going to the inferior hypogastric plexus. These nerves provide parasympathetic innervation to the pelvic viscera and the GI tract distal to the left colic flexure. (Remember, the vagus gives parasympathetic innervation to the rest of the gut.) Sacral splanchnic nerves come off the sacral sympathetic chain ganglia, carrying sympathetic fibers that will go to the inferior hypogastric plexus. To remember the difference between the pelvic and sacral splanchnics, just remember that the sacral splanchnics are named after a spinal cord segment, just like the thoracic, lumbar, and cervical splanchnics that you know and love. These all carry sympathetic fibers. Pelvic splanchnics are not named after a spinal cord segment and they're different--they carry parasympathetic fibers. The grey rami communicantes are structures that postganglionic sympathetic neurons travel on to get out of the sympathetic trunk and rejoin a spinal nerve. There are gray rami in the pelvis. The white rami communicantes are structures that preganglionic sympathetic fibers use to get out of a spinal nerve to enter the sympathetic trunk. White rami are seen between the T1 to L2 levels, but not in the pelvis. Finally, the hypogastric nerves carry postganglionic sympathetic nerves from the superior hypogastric plexus to the inferior hypogastric plexus.

A condensation of fibrous tissue in the female located at the center of the posterior border of the perineal membrane is the: a) Frenulum b) Posterior labial commissure c) Perineal body d) Anococcygeal ligament e) Pubovesical ligament

c) perineal body The perineal body is an irregular fibromuscular mass located at the center of the posterior border of the perineal membrane. It is the site where many muscles converge, including bulbospongiosus, external anal sphincter, and the superficial and deep transverse perineal muscles. This is found only in females; the male homolog for this structure is the central tendinous point. Frenulum is a word that refers to a small fold, and there are two in the female perineum, so this isn't even specific enough to be a good answer. The frenulum of the clitoris is a structure lying deep to the clitoris, formed by the deep labia minora. This structure is not near the posterior border of the perineal membrane; it is clearly in the urogenital triangle. There is also a frenulum of the labia minora which is just anterior to the perineal body, also in the urogenital triangle. Although the frenulum of the labia minora is sort of superficial to the center of the posterior border of the perineal membrane, the question is asking for a structure that is closely associated with the perineal membrane. This means that structures of the external genitalia will be wrong answers. The posterior labial commissure is another structure of the external genitalia which is located over the posterior border of the perineal membrane, and it's also a wrong answer for the same reason. The anococcygeal ligament is a ligament that attaches the external anal sphincter to the coccyx. It is located in the anal triangle. The pubovesicular ligament attaches the bladder to the pubic bone. It is more associated with the pelvic viscera as opposed to the perineum.

What part of the ischioanal (ischiorectal) fossa extends deep to the sacrotuberal ligament? a) Anterior recess b) Genital hiatus c) Posterior recess d) Pudendal canal

c) posterior recess The ischioanal fossa is a space found on both sides of the anal canal. It is bounded laterally by the obturator internus, superiorly by the pelvic diaphragm, and medially by the pelvic diaphragm and anus. It is the area that is lateral to the anal canal and inferior to the pelvic diaphragm. The anterior recesses are the parts of the ischioanal fossa that extend above the perineal membrane, and the posterior recesses extend deep to the sacrotuberal membrane and superior to the gluteus maximus. The genital hiatus is the place where the pelvic diaphragm splits to allow the urethra/vagina and anus to pass through. The pudendal canal travels from the lesser sciatic foramen, where its contents enter the perineum. It contains the internal pudendal artery, internal pudendal vein, and pudendal nerve.

Which of the following would be most likely to be damaged by a stab wound into the ischiorectal (ischioanal) fossa 2 cm lateral to the anal canal? a) Crus of the Penis b) Perineal Body c) Pudendal Nerve d) Inferior Rectal Artery e) Vesicular Bulb

c) pudendal nerve The pudendal nerve is found about 2 cm lateral to the anal canal. Therefore, it is the structure most likely to be damaged by the stab wound. The crus of the penis is the lateral part of the corpus cavernosum found at the base of the penis. It is anterior, not lateral, to the anal canal. The perineal body is a structure found in the female only--it is a fibromuscular mass found in the plane between the anal canal and the perineal membrane that serves at the convergence of several muscles. It is anterior to the anal canal. The inferior rectal artery is a branch of the internal pudendal artery that delivers blood to the inferior part of the rectum. It would not be injured by the stabbing because it is located on the surface of the rectum, not 2 cm lateral to the anal canal. Finally, the vesicular bulb is a structure of erectile tissue located on either side of the vestibule of the vagina, attached to the perineal membrane. So, it would be anterior to the site of the stabbing.

The most inferior extent of the peritoneal cavity in the female is the: a) Pararectal fossa b) Paravesical fossa c) Rectouterine pouch d) Rectovesical pouch e) Vesicouterine pouch

c) rectouterine pouch Remember: The rectouterine and vesicouterine pouches are the two pouches created by draping the peritoneum over the pelvic organs. These pouches are the two lowest extents of the peritoneal cavity, so to answer this question, you just need to decide which one goes lower. Since the uterus is folded over the bladder, the rectouterine pouch can extend to a slightly lower level than the vesicouterine pouch, which makes C the correct answer. The pararectal fossa is formed by lateral reflections of perineum over the superior one third of the rectum; this space gives the rectum room to fill with feces. The paravesicular fossa is a space near the bladder that allows the bladder to expand. Why is the rectovesicular pouch incorrect? It's only found in males, not females! (But, if the question had asked about males, the rectovesicular pouch would have been the correct answer.)

The prostate is often imaged using an ultrasound transducer placed in which location? a) Penis b) Perineum c) Rectum d) Urethra e) Urinary Bladder

c) rectum The prostate is located on the posterior side of the bladder. Since the rectum is behind the bladder and prostate, you can image the prostate by placing an ultrasound transducer in the rectum and pressing it against the anterior wall. Then, the ultrasound transducer will be against the prostate gland.

The perineum is bounded by all of the following skeletal elements except: a) coccyx b) ischiopubic ramus c) spine of ischium d) symphysis pubis

c) spine of the ischium The bounderies of the perineum are as follows. Anterior: pubic symphysis; Anterolateral: ischiopubic rami; Lateral: ischial tuberosities; Posterolateral: sacrotuberous ligament; Posterior: tip of the coccyx. The spine of the ischium, which projects into the pelvis toward the lateral pelvic wall, does not make up a boundary of the perineum

Which statement about the pelvic floor is NOT correct? a) Along with the pelvic brim, it defines the true pelvic cavity b) It is a funnel-shaped skeletal muscle c) It is referred to as the pelvic diaphragm d) It is tensed during defecation e) It projects into the anal triangle

d) It is tensed during defecation. The pelvic floor is not tensed during defecation--it is relaxed so that feces can be released from the rectum. When rectal stretch receptors are stimulated, afferent impulses are sent to the spinal cord (which mediates local reflexes) and to the brain (which alerts the body of the urge to defecate). The pelvic splanchnic nerves mediate local parasympathetic reflexes that cause the rectal musculature to contract and the internal sphincter to relax. These reflexes are promoting the expulsion of feces. However, the external sphincter and levator ani muscles can be voluntarily contracted--they receive somatic innervation from the pudendal and levator ani nerves. This contraction allows feces to be retained until a suitable time. So, tensing the pelvis floor does not expel feces--it retains feces. The area between the pelvic floor and the pelvic brim is the true pelvic cavity. This is the area that contains the pelvic viscera. Pelvic diaphragm is another name for the pelvic floor, and it is mostly made by levator ani, a funnel-shaped muscle. The pelvic floor also projects into the anal triangle, a space bounded by the posterior margin of the perineal membrane and the two sacrotuberous ligaments.

During a hysterectomy, the uterine vessels are ligated. However, the patient's uterus continues to bleed. The most likely source of blood still supplying the uterus is from which artery? a) Inferior vesical b) Internal pudendal c) Middle rectal d) Ovarian e) Superior vesical

d) Ovarian The ovarian artery has branches which supply the uterus. In fact, this artery anastomoses with the uterine artery. So, if the uterus is still bleeding after ligating the uterine artery, the ovarian artery is probably supplying the uterus. The inferior vesical artery supplies the inferior part of the bladder--it anastomoses with the middle rectal artery. The internal pudendal artery supplies blood to the perineum. The middle rectal artery supplies blood to the rectum. The superior vesical artery supplies blood to the superior bladder.

During a prostatectomy, the surgeon attempts to protect the prostatic plexus of nerves which contains nerve fibers that innervate penile tissue to cause erection. From which nerves do these fibers originate? a) Deep perineal b) Dorsal nerve of the penis c) Genitofemoral d) Pelvic splanchnics e) Pudendal

d) Pelvic splanchnics Erection is mediated by parasympathetic nerves, and the pelvic splanchnic nerves are the parasympathetic nerves that innervate the smooth muscle and glands of all pelvic viscera. So, the pelvic splanchnic nerves are the nerves contributing the fibers to the prostatic plexus which innervate penile/clitoral erectile tissue to cause erection. None of the other listed nerves carry parasympathetic fibers which could innervate the penis and cause erection. Additionally, none of these other nerves contribute to the prostatic plexus, which is an extension of the inferior hypogastric plexus. The deep perineal nerve is the a branch of the perineal nerve that innervates all the muscles of the urogenital triangle. The dorsal nerve of the penis/clitoris is a branch of the pudendal nerve that provides sensory innervation to the skin of the shaft of the penis/clitoris. The genitofemoral nerve provides motor innervation to the cremaster muscle and sensory innervation to the skin of the anterior scrotum/labium majus and the upper medial thigh. Finally, the pudendal nerve is the major nerve of the perineal region. Its branches include the inferior rectal nerve, perineal nerve, and the dorsal nerve of the penis/clitoris.

A patient presents complaining of blood-stained stools and the inability to completely empty his rectum. He also has pain along the back of his thigh and weakness of the posterior thigh muscles. Digital examination reveals a tumor in the posterolateral wall of the rectum. Pressure on what nerve plexus could cause the pain in his lower limb? a) Inferior hypogastric b) Inferior mesenteric c) Lumbar d) Sacral e) Superior hypogastric

d) Sacral plexus The sacral plexus includes contributions from L4 through part of S4. It supplies motor innervation to muscles of the pelvic diaphragm, muscles of the urogenital diaphragm, and muscles of the posterior hip, posterior thigh, leg and foot. It supplies sensory innervation to the skin of the perineum, posterior thigh, leg and foot. So, this patient's pain and weakness in the thigh, as well as his inability to empty his rectum, point to damage in the sacral plexus. The inferior hypogastric plexus lies between the pelvic viscera and the pelvic wall-- it supplies sympathetic innervation to the vascular smooth muscle of the pelvic vessels and parasympathetic innervation to the pelvic viscera (from the pelvic splanchnic nerves). The inferior mesenteric plexus supplies sympathetic innervation to the smooth muscle of the vessels supplying the descending colon, sigmoid colon and rectum. The lumbar plexus innervates the muscles of the lower abdominal wall, the cremaster muscle, psoas major and minor, quadratus lumborum,and iliacus. Finally, the superior hypogastric plexus is the continuation of the intermesenteric plexus--it supplies the vascular smooth muscle of the pelvic viscera and transmits pain sensation from the pelvic viscera.

A caudal epidural block is a form of regional anesthetic used in childbirth. Within the sacral canal, the anesthetic agent bathes the sacral spinal nerve roots which would anesthetize all of the following nerves except: a) Pelvic splanchnics b) Pudendal c) S2 dorsal root d) Sacral splanchnics e) S2 ventral primary ramus

d) Sacral splanchnics The sacral splanchnic nerves do not come out of the sacral nerve roots--instead, these nerves come from the sacral sympathetic ganglia. So, anesthesia bathing the sacral nerve roots would not affect the sacral splanchnic nerves, which are coming from the sympathetic trunk. The sacral splanchnic nerves contribute to the inferior hypogastric plexus and provide sympathetic innervation to the vascular smooth muscle of the pelvic viscera. The pelvic splanchnic nerves are comprised of fibers from S2, 3, and 4, and pudendal nerve is made of the ventral primary rami of S2-4. These nerves would be numbed if the sacral nerve roots were anesthetized. Finally, the S2 dorsal root and S2 ventral primary ramus would also be anesthetized by the caudal epidural block.

A patient complains of a boil located on her labia majora. Lymphatic spread of the infection would most likely enlarge which nodes? a) Lumbar nodes b) Sacral nodes c) External iliac nodes d) Superficial inguinal nodes e) Internal iliac nodes

d) Superficial inguinal lymph nodes The perineum and the external genitalia, including the labia majora and scrotum, drain to the superficial inguinal lymph nodes. However, in the male, remember that the testes do not drain to the superficial inguinal lymph nodes! The lymphatic vessels for testes travel in the spermatic cord and drain the testes into the lumbar nodes (ovaries also drain to lumbar nodes). The lumbar nodes drain the internal pelvic organs; the sacral nodes drain the prostate gland, uterus, vagina, rectum, and posterior pelvic wall; the external iliac nodes drain the lower limb; the internal iliac nodes drain the pelvis and gluteal region.

The rectouterine pouch is the lowest extent of the female peritoneal cavity. At its lowest, it provides a coat of peritoneum to a portion of the: a) urinary bladder b) urethra c) uterine cervix d) vagina

d) Vagina In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. At its lowest extent, the rectouterine fold is draped over the posterior fornix of the vagina. This means that surgeons can make an incision in the posterior fornix of the vagina and enter the rectouterine pouch to harvest eggs from the ovaries or remove an ectopic pregnancy. Take a look at Netter Plate 337 for a picture of this relationship.

Which of the following developmental processes is least likely to be involved in the differentiation of male external genitalia from the indifferent state? a) Descent of the gonads into the labio-scrotal folds b) Fusion of the urogenital folds c) Elongation of the phallus d) Formation of new erectile bodies

d) formation of new erectile bodies Males and females have analogous erectile bodies. The three main erectile bodies in males are 2 corpus cavernosa and a corpus spongiosum. Females have 2 corpus cavernosa plus 2 vestibular bulbs which are analogs to the corpus spongiosum. So, females actually have more erectile bodies than males. Development differs, however, in many other ways. Remember: the gubernaculum pulls the testes to descend into the scrotum, but the ovaries stop their descent and remain in the pelvis. The urogenital folds fuse in males to create the raphe of the penis. However, they stay open in females to create the labial minora and perineal raphe. Finally, the phallus elongates in males but not in females.

Which of these features of the anal canal serves to indicate the point where the mucosal covering of the gastrointestinal tract ends and a skin-like covering begins? a) Mucosal zone b) White line c) Transitional zone d) Pectinate line

d) pectinate line The pectinate line is the line of transition between the mucosal lining of the anal canal and the skin lining of the anal canal. So, this is the point where the mucosal zone ends and the skin begins. The white line is a transitional zone between the pectinate line and "regular" skin where there are some more subtle changes in the epithelial lining of the anal canal. But the pectinate line is the line that demarcates the major transition from mucosal lining to skin.

A structure which takes the form of a hood anterosuperior to the clitoris: a) Frenulum of the clitoris b) Labia majora c) Labia minora d) Prepuce

d) prepuce The prepuce is a fold of smooth skin that extends over the glans clitoris. It is formed by the joining of the anterior divisions of the labia minora. The frenulum of the clitoris is a small fold found posterior to the clitoris. It is formed by the joining of deeper, posterior, divisions of the labia minora. The labia majora are fat-filled elevations of skin lying on each side of the vestibule of the vagina. The labia minora are smaller folds of skin lying medial to the labia majora. They extend posteriorly and inferiorly from the clitoris.

Which structure is found only in males? a) Anterior recess of ischoianal fossa b) Genital Hiatus c) Ischiocavernosus muscle d) Rectovesical pouch e) Sphincter urethrae muscle

d) rectovesicular pouch The rectovesicular pouch is a reflection of the peritoneum between the rectum and the bladder. It can only be found in males because females have the uterus sitting between the rectum and the bladder. This means that females have two pouches created by reflections of peritoneum draped over the pelvic viscera: the rectouterine and vesicouterine pouches. The ischioanal fossa is the fat filled space located lateral to the anal canal and inferior to the pelvic diaphragm. It has an anterior recess that extends superior to the perineal membrane and sphincter urethrae muscle, and it is found in both males and females. The genital hiatus is also found in both sexes--it is the place where the urethra/vagina and anus exit the pelvic diaphragm. The ischiocavernosis muscle compresses the corpus cavernosum of the penis or clitoris. Finally, the sphincter urethrae encircles and compresses the urethra in both sexes.

A 6 mo. old male was brought to the pediatric clinic by his parents because of leakage of urine from the ventral surface of his penis. This congenital condition, hypospadias, is due to incomplete ventral closure of a component of the penis. Which of the below structures would be partially open for urine to take such a course? a) Shaft of corpus cavernosum b) Membranous urethra c) Glans d) Shaft of corpus spongiosum

d) shaft of the corpus spongiosum Since the urine is leaking through the ventral side of the penis, it must be leaking through a defect in the spongy urethra. The spongy urethra is contained in the corpus spongiosum, so it follows that the corpus spongiosum must be open. The membranous urethra is a brief portion of the urethra extending from the bottom of the prostate to the top of the corpus spongiosum. A defect here would not cause leakage on the ventral surface of the penis. The corpora cavernosa are erectile bodies that lie beside the corpus spongiosum. They are not involved with the flow of urine or the urethra. The glans of the penis is at the tip - if this structure failed to close, there would be abnormal leakage from the tip of the penis, not the ventral surface.

A malignant tumor in the cutaneous zone of the anal canal would most likely metastasize (spread) to which group of lymph nodes? a) Inferior mesenteric b) Pararectal c) Sacral d) Superficial inguinal

d) superficial inguinal lymph nodes Remember, the pectinate line (the line in the anus where mucosa changes to skin) is the dividing line for lymphatic drainage. Structures above the pectinate line drain into the inferior mesenteric and internal iliac nodes. Structures below the pectinate line drain into the superficial inguinal nodes. Since the tumor is in the cutaneous (skin) region of the anal canal, it is going to be drained by the superficial inguinal nodes. This means that these nodes would be the first site of metastases.

Which structure does NOT form part of the boundary defining the trigone of the bladder? a) Interuteric crest b) Left Ureteric Orifice c) Right Ureteric Orifice d) Urachus e) Urethral Orifice

d) urachus The trigone of the bladder is bounded by the openings of the left and right ureteric orifices superolaterally, the interureteric crest between the openings of the ureters and the internal urethral orifice inferiorly. The urachus is the structure that joins the apex of the fetal bladder to the umbilicus. After birth, it becomes the median umbilical ligament.

The prostate gland: a) Contains upper, middle and lower lobes b) Encircles the urethra c) Is well imaged radiologically using an intravenous urogram d) Is extraperitoneal e) B and D

e) B and D There are two true statements here. First, the prostate gland encircles the urethra. It circles around the first part of the urethra, the prostatic urethra. This is why urinary retention is one symptom of prostatic hypertrophy--if the prostate is enlarged, it may close around the urethra, occluding this passage and preventing urine from exiting the bladder. The prostate gland is also extraperitoneal. Remember: the rectovesicular pouch, a fold of peritoneum that hangs between the bladder and rectum, is the lowest extent of the peritoneal cavity in males . But, the prostate is found on the posterior side of the bladder, below the point where the peritoneal membrane created this fold. So, it is an extraperitoneal organ. The lobes of the prostate are: anterior, posterior, lateral, and middle. Finally, the prostate would not be imaged using an intravenous urogram. In an intravenous urogram, a patient is given IV contrast, and radiographic images are taken as the contrast is excreted, passing through the kidneys, ureters, and bladder. Since the prostate is not part of this excretory pathway, it would not be viewed through this method.

If the venous drainage of the anal canal above the pectinate line is impaired in a patient with portal hypertension, there may be an increase in blood flow downward to the systemic venous system via anastomoses with the inferior rectal vein, which is a tributary of the: a) External iliac b) Inferior gluteal c) Inferior mesenteric d) Internal iliac e) Internal pudendal

e) Internal pudendal The rectal venous plexus is one of the four portal/systemic anastomoses. Blood from the portal system can flow into the venous system at this junction. This means that portal blood, from the superior rectal vein, could flow through the rectal venous plexus, into the inferior rectal vein and into the systemic venous drainage. Now, you just need to figure out what the inferior rectal vein drains into. And it drains into the internal pudendal vein, so that's the answer. See Netter plate 370 for a picture illustrating this concept of the portal/systemic anastomosis in the rectum. The external iliac vein is one of the two branches of the common iliac vein (along with the internal iliac vein). However, the internal iliac vein and its tributaries (including the pudendal vein) are much more important in draining the pelvic structures. The inferior gluteal vein is a branch of the anterior division of the internal iliac vein--it drains gluteus maximus. The inferior mesenteric vein is part of the portal venous system--it gives rise to the superior rectal veins, but not the inferior rectal veins!

In order to perform an episiotomy prior to childbirth, the perineum must be anesthetized. By inserting a finger in the vagina and pressing laterally, what palpable bony landmark can be used as the posterior limit of the pudendal canal? a) Coccyx b) Ischial tuberosity c) Ischiopubic ramus d) Obturator groove e) Ischial spine

e) Ischial spine The pudendal canal travels from the lesser sciatic foramen to the deep transverse perineus muscle. The ischial spine marks the posterior limit of the pudendal canal, so that's the correct answer. If you weren't sure about that, you might also notice that the physician here is trying to perform a transvaginal pudendal nerve block. This means that the physician will be using the ischial spine as a landmark and inserting the needle near this prominence, coating the pudendal nerve with anesthesia before it gives off its branches. The coccyx is the inferior end of the vertebral column; it is on the posterior wall of the pelvis. The ischial tuberosity (not to be confused with the ischial spine!) protrudes posteroinferiorly from the body of the ischium. It is the attachment for the sacrotuberous ligament. The ischiopubic ramus is the articulation between the ischial ramus and the inferior pubic ramus in the anterior pubis. The obturator groove is a groove on the inferior surface of the superior pubic ramus. It marks the area of passage of the obturator vessels and nerve in the obturator canal.

An elderly patient is having difficulty in voiding (urinating). He complains that after voiding, he still feels as though he needs "to go" again. You suspect that this patient suffers from benign prostatic hypertrophy, which has caused enlargement of the __________ of the bladder. a) seminal colliculus b) interureteric crest c) ampulla d) trigone e) uvula

e) Uvula The uvula of the bladder is an elevation on the posterior wall of the bladder. The uvula is produced by the middle lobe of the prostate gland. If the prostate becomes enlarged (either by benign hypertrophy or malignancy) the uvula can constrict the internal urethral orifice and cause difficulty in voiding the bladder. The seminal collicus is an elevation on the posterior wall of the prostatic urethra. The interureteric crest is an elevation on the posterior wall of the bladder, between the two ureteric orifices. The ampulla of the ductus deferens is the dilated part of the ductus deferens located posterior to the bladder. It joins with the duct of the seminal vesical to form the ejaculatory duct. The trigone is a triangular area on the posterior wall of the bladder. It is delineated by the two ureteric orifices and the internal urethral orifice, which form an equilateral triangle known as the trigone.

The part of the male reproductive tract which carries only semen within the prostate gland is the: a) Prostatic urethra b) Membranous urethra c) Seminal vesicle d) Ductus deferens e) Ejaculatory duct

e) ejaculatory duct The ejaculatory duct is a duct which courses through the prostate gland and contains only semen. Remember, semen is the combination of sperm from the ductus deferens, seminal fluid from the seminal vesicle, and secretions of the prostate gland. The ejaculatory duct is formed by the union of the duct of the seminal vesicle and the ampulla of the ductus deferens, and it is the site where sperm and seminal fluid mix. The prostatic urethra is also contained in the prostate gland, and it carries semen, but it also carries urine out of the bladder. The membranous urethra is the continuation of the prostatic urethra outside of the prostate gland, and it carries both semen and urine as well. The seminal vesicle is a structure on the posterior surface of the bladder that produces seminal fluid. The ductus deferens is a passageway that carries sperm from the epididymis to the ejaculatory duct.

Following pregnancy and delivery, a 32-year-old woman continued to have problems with urinary incontinence which developed during pregnancy. Her obstetrician counseled her to strengthen the muscle bordering the vagina and urethra, increasing its tone and exerting pressure on the urethra. This physical therapy was soon adequate to restore urinary continence. What muscle was strengthened? a) Coccygeus b) Ischiocavernosus c) Obturator Internus d) Piriformis e) Puborectalis

e) puborectalis Puborectalis is the part of levator ani that is closest to the vagina and urethra. This muscle may be injured during a difficult childbirth. By doing Kegel exercises, where women contract and relax the pelvic floor, these injured muscles may be strengthened and urinary continence may be improved. Besides levator ani, coccygeus is the second muscle that makes the pelvic floor. However, it extends between the ischial spine and the side of the coccyx/lower sacrum, so it is not next to the vagina and urethra and is not important for maintaining urinary continence. Ischiocavernosus compresses the corpus cavernosum. It is closely applied to the crus penis/clitoris in the perineum. Obturator internus and piriformis laterally rotate and abduct the thigh. Although these muscles originate in the pelvis, they are functionally more important to the lower limb.

The boundaries of the perineum include all the following except: a) Ischiopubic rami b) Ischial tuberosity c) Tip of the coccyx d) Sacrotuberal ligament e) Sacrospinal ligament

e) sacrospinal ligament The sacrospinal ligament connects the sacrum to the ischial spine. Together with the sacrotuberous ligament, it converts the greater and lesser sciatic notches into greater and lesser sciatic foramina. However, it is not near the perineum--it is more important as a landmark that creates the greater and lesser sciatic foramina which helps to organize the structures exiting the pelvis. The bounderies of the perineum are as follows. Anterior: pubic symphysis; Anterolateral: ischiopubic rami; Lateral: ischial tuberosities; Posterolateral: sacrotuberous ligament; Posterior: tip of the coccyx. These boundaries create two triangles in the perineum: the urogenital triangle and the anal triangle. The urogenital triangle is the anterior subdivision, bounded by the pubic symphysis, ischiopubic rami, and the posterior margin of the perineal membrane, which corresponds to an imaginary line between the two ischial tuberosities. The anal triangle is the posterior division of the perineum. It starts off where the urogenital triangle ends: at the posterior margin of the perineal membrane. Then, it is bounded by the sacrotuberous ligament and the tip of the coccyx. It's important to look at these triangles and orient yourself to them using the bones in your bone set--you'll realize that the perineum is not contained in one flat plane; instead, the triangles are at angles to each other.

An elderly male patient presents with dysuria and urgency. You suspect benign prostatic hypertrophy which has caused an enlargement of the: a) interureteric crest b) prostatic utricle c) seminal colliculus d) sphincter urethrae e) uvula

e) uvula The uvula of the bladder is an elevation on the posterior wall of the bladder. The uvula is caused by the middle lobe of the prostate gland. If the prostate becomes enlarged (either by benign hypertrophy or malignancy), the uvula can constrict the internal urethral orifice and cause difficulty in voiding the bladder. The interureteric crest is an elevation on the posterior wall of the bladder, between the two ureteric orifices. The seminal collicus is an elevation on the posterior wall of the prostatic urethra. At the summit of the seminal collicus, you can find the prostatic utricle, which is a small blind diverticulum in the posterior wall of the prostatic urethra. Finally, the sphincter urethrae is a muscle which encircles the urethra and compresses the urethra. None of these other structures would be enlarged in a case of benign prostatic hypertrophy.