SM_220-221b: Anatomy of the Pelvis and Perineum I and II

Question 2

___ is the diamond-shaped pelvic outlet

Answer 2

Perineum is the diamond-shaped pelvic outlet

Question 3

Perineum is subdivided into the ____ and ____

Answer 3

Perineum is subdivided into the anterior urogenital triangle and posterior anal triangle

Question 4

Perineum has superior boundary of ____ and lateral boundary of ____

Answer 4

Perineum has superior boundary of pelvic diaphragm and lateral boundary of obturator internus muscle

Question 5

Urogenital diaphragm is ____ closing off the urogenital triangle

Answer 5

Urogenital diaphragm is two fascial layers closing off the urogenital triangle

• Superior fascia of urogenital diaphragm
• Inferior fascia (perineal membrane)

Question 6

____ is deep to urogenital diaphragm

Answer 6

Pelvic diaphragm is deep to urogenital diaphragm

Question 7

Describe perineum landmarks in midsagittal segment

Answer 7

Perineum landmarks in midsagittal segment

• Male: UG diaphragm is always in line with pubic symphysis and perineal body in front of the rectum
• Female: UG diaphragm and perineal body are in line with pubc symphysis

Question 8

Pubovesicular ligmanent in the female is analogous to ___ in the male

Answer 8

Pubovesicular ligmanent in the female is analogous to puboprostatic ligament in the male

Question 9

Muscles in the UG diaphragm are ____ and ____

Answer 9

Muscles in the UG diaphragm are external urethral sphincter and deep transverse perineal muscle

• Bulbourethral gland in male is also within UG diaphragm
• Greater vestibular gland in female is superficial to UG diaphragm

Question 10

Deep pouch is ____, while the superficial pouch is ____

Answer 10

Deep pouch is interior of the UG diaphragm, while the superficial pouch is the scrotum or labia majora (superficial body wall)

Question 11

Superficial pouch of Colle’s fascia is tightly attached to the ____ and ____

Answer 11

Superficial pouch of Colle’s fascia is tightly attached to the back edge of the UG diaphragm and perineal body and fascia lata of the thigh

• Blood or urine in the superficial pouch can only pass upward into the body wall between the superficial and deep layers

Question 12

Superficial pouch contains ____

Answer 12

Superficial pouch contains everything superficial to the UG diaphragm

Question 13

Diaphragms from deep to superficial are ____ and ____

Answer 13

Diaphragms from deep to superficial are pelvic diaphragm and UG diaphragm

• Pelvic diaphragm: levator ani (pubococccygeus, iliococcygeus), ischiococcygeus
• UG diaphragm: superficial fascia and inferior fascia (perineal membrane)

Question 14

Describe contents of the superficial pouch of the UG diaphragm

Answer 14

Contents of the superficial pouch of the UG diaphragm

• Bulb and crura of penis, clitoris, vestibular bulb, and greater vestibular gland
• Bulbospongiosus, ischiocavernosus, and superficial transverse perineal muscles in both sexes

Question 15

___ is enlarging the birth canal for an anticipated difficult birth

Answer 15

Episiotomy is enlarging the birth canal for an anticipated difficult birth

Question 16

Midline episiotomy involves cutting ____

Answer 16

Midline episiotomy involves cutting the central tendon of the perineum (and wall of vagina)

Question 17

Mediolateral episiotomy involves cutting the ____

Answer 17

Mediolateral episiotomy involves cutting the UG diaphragm, bulbospongiosus, and superficial transverse perineal muscles

Question 18

____ is somatic innervation (S2-4) for perineum body wall

Answer 18

Pudendal nerve is somatic innervation (S2-4) for perineum body wall

• Perineum body wall: UG diaphragm, genitalia, external anal sphincter, and skin of perineum
• Branches: inferior rectal branch, perineal, and dorsal nerve of penis

Question 19

___ enter the superior hypogastric plexus, while ___ leave the S2-4 ventral rami

Answer 19

Lumbar splanchnics enter the superior hypogastric plexus, while pelvic splanchnics leave the S2-4 ventral rami

• Visceral sensory neurons are in all autonomic nerves and plexuses

Question 20

___ exit with ventral roots T1-L2

Answer 20

Sympathetics exit with ventral roots T1-L2

Question 21

___ travels from sacral plexus to external anal sphincter and perineum

Answer 21

Pudendal nerve (S-4) travels from sacral plexus to external anal sphincter and perineum

Question 22

Describe nerve functions

Answer 22

Nerve functions

• Somatic (sacral ventral rami): body wall (skin of perineum, UG and pelvic diaphragms, external anal sphincter, external genital organs)
• Sympathetic (lumbar splanchnics): arteries, internal sphincters, ureters, and ductus deferens
• Parasympathetic (pelvic splanchnics): bladder (micturition), rectum (defecation, peristalsis), and erection of penis / clitoris

Question 23

Pudendal nerve block anesthetizes ____

Answer 23

Pudendal nerve block anesthetizes UG diaphragm and perineum

Question 24

Sacral epidural nerve block anesthetizes ____

Answer 24

Sacral epidural nerve block anesthetizes UG diaphragm, perineum, and cervix

Question 25

\_\_\_\_ nerve block is the anesthesia of choice for childbirth

Answer 25

Lumbar epidural nerve block via catheter is the anesthesia of choice for childbirth * Uterus has lower thoracic and lumbar spinal segments

Question 26

Sacral epidural block anesthetizes \_\_\_\_

Answer 26

Sacral epidural block anesthetizes cervix and all of vagina * S2, 3, and 4 via pelvic splanchnic nerves * Somatic innervation between pudendal nerve

Question 27

Describe branches of the internal iliac artery

Answer 27

Internal iliac artery branches

Question 28

Describe exceptions to an internal iliac artery source of blood

Answer 28

Exceptions to an internal iliac artery source of blood * Upper rectum: inferior mesenteric * Gonads: aorta, inferior vena cava, left renal vein * Dorsal veins of penis / clitoris go under the pubic symphysis to the pelvic plexus rather than following the pudendal canal route

Question 29

Describe the male system

Answer 29

Male system

Question 30

Describe erectile tissues of the penis

Answer 30

Erectile tissues of the penis * Left and right crus * Bulb * Corpus cavernosum * Corpus spongiosum * Glans penis

Question 31

\_\_\_\_ muscle envelops each crus, while the ____ muscle envelops the bulb and proximal corpus spongiosum

Answer 31

Ischiocarvernosus muscle envelops each crus, while the bulbospongiosus muscle envelops the bulb and proximal corpus spongiosum

Question 32

Each crus continues as the \_\_\_\_, and the bulb continues as the \_\_\_\_

Answer 32

Each crus continues as the corpus cavernosum dorsally, and the bulb continues as the corpus spongiosum ventrally

Question 33

Describe innvervation of the perineum and external genital organs

Answer 33

Innvervation of the perineum and external genital organs * Deep artery of penis to corpus cavernosus * Artery to bulb * Dorsal nerve / artery / vein to penis clitoris * Perineal nerve

Question 34

Describe prostate enlargement

Answer 34

Prostate enlargement * Outer zone tumors usually cancerous * Inner zone (median lobe) tumors usually benign and very common * Effects similar to kidney stones except the bladder is also involved (diverticula and trabeculation of the muscular wall)

Question 35

Describe prostate surgery and pelvic nerves

Answer 35

Prostate surgery and pelvic nerves * Removal of the prostate can be done through the urethra, above public bone, or through the perineal body * If via perineal body, parasympathetics from the pelvic plexus to the penis can be cut, resulting in impotence

Question 36

Describe female external genitalia

Answer 36

Female external genitalia * Labia majora: folds of superficial body wall * Labia minora: flank vestibule (space of the glans with the clitoris and openings of the vagina, urethra, and greater vestibular glands)

Question 37

\_\_\_\_ surrounds the vestibular bulb and greater vestibular gland

Answer 37

Bulbospongiosus muscle surrounds the vestibular bulb and greater vestibular gland

Question 38

Vagina is primarily \_\_\_\_

Answer 38

Vagina is primarily retroperitoneal * Has no glands and few sensory nerves

Question 39

Cervix and fundus are \_\_\_\_, while most of the body is \_\_\_\_

Answer 39

Cervix and fundus are retroperitoneal, while most of the body is peritonealized (in a mesentery)

Question 40

\_\_\_ is the angle between vagina and uterus

Answer 40

Anteversion is the angle between vagina and uterus

Question 41

\_\_\_ is the angle between the cervix and the body of the uterus

Answer 41

Anteflexion is the angle between the cervix and the body of the uterus

Question 42

\_\_\_\_ is retroversion where the uterus is tipped backward in line with the vagina

Answer 42

Tipped uterus is retroversion where the uterus is tipped backward in line with the vagina

Question 43

Describe ligaments of uterus

Answer 43

Ligaments of uterus

Question 44

Describe the broad ligament of the uterus

Answer 44

Broad ligament of the uterus * Mesosalpyinx: upper part of broad ligament * Mesovarium: posterior extension of broad ligament * Mesometrium: broad ligament

Question 45

Ovarian artery of the aorta reaches ovary through \_\_\_\_

Answer 45

Ovarian artery of the aorta reaches ovary through suspensory ligament of the ovary (lateral part of broad ligament) * Uterine artery from internal iliac