Sievert: Anal Triangle

Question 1

What does the sacrospinous ligament connect?

Answer 1

the sacrum to the ischial spine

Question 2

What does the sacrotuberous ligament connect?

Answer 2

the sacrum to the ischial tuberosity

Question 3

Above the ischial spine is a large notch, the (blank), which is converted into a foramen by the sacrospinous ligament

Answer 3

greater sciatic notch

Question 4

Final segment of vertebral column

Answer 4

coccyx

Question 5

Why are the greater and lesser sciatic foramen important?

Answer 5

They allow for nerves and vessels to leave the pelvis and enter the perineum without puncturing the pelvic floor.

Question 6

The obturator foramen is filled with the (blank)

Answer 6

obturator membrane

Question 7

What two muscles arise from the obturator membrane and act on the hip joint?

Answer 7

the obturator externus and the obturator internus

Question 8

How does the obturator internus leave the pelvis to attach to the femur?

Answer 8

It passes through the lesser sciatic foramen

Question 9

The area inferior to the pelvic diaphragm between the coccyx and the pubis and including all the structures in the two triangles

Answer 9

perineum

Question 10

Pyramidal fibromuscular mass in the middle line of the perineum at the junction between the urogenital triangle and the anal triangle

Answer 10

perineal body

Question 11

Perineal body is found in both males and females. In males, it is found between the (blank) and the anus; in females, is found between the (blank) and anus

Answer 11

bulb of the penis; vagina

Question 12

Two muscles that make up the pelvic floor

Answer 12

levator ani and coccygeus

Question 13

T/F: There is a dense connective tissue membrane over the obturator internus that forms a tendinous arch

Answer 13

True

Question 14

The anal triangle in the female is identical to that of the male, but the UG triangle in the female has an additional opening for the (blank)

Answer 14

vagina

Question 15

How do you get nerves and blood vessels out of the pelvis?

Answer 15

Through the greater sciatic foramen

Question 16

Vessels and nerves can leave the pelvis through the greater sciatic foramen and then pass into the perineum by running superficial to the (blank) lig. but deep to the (blank) lig

Answer 16

sacrospinous; sacrotuberous

Question 17

What is the purpose of the vessels leaving the pelvis through the greater sciatic foramen to enter the perineum?

Answer 17

Does not compromise the integrity of the pelvic floor

Question 18

Boundaries of the ischio anal fossa

Answer 18

Medial: external anal sphincter and Pelvic diaphragm
Lateral: obturator muscle and ischium
Superior: pelvic diaphragm
Posterior: sacrotuberous lig. and gluteus maximus Inferior: Skin
Anterior boundary extends all the way forward to the pubis as the anterior recess

Question 19

3 things in the anal triangle

Answer 19

1. anal canal
2. ischioanal fossa
3. pudendal nerves and vessels as they pass thru on their way to the UG triangle

Question 20

As the pudendal nerves pass through the anal triangle toward the UG triangle, what is the first branch they give off?

Answer 20

inferior rectal vessels and nerves

Question 21

THis muscle is key, because superior gluteal nerves and vessels enter the gluteal region superior to the muscle, while inferior gluteal nerves and vessels enter inferior to this muscle

Answer 21

piriformis muscle

Question 22

The pudendal nerve exits the pelvis via the greater sciatic foramen, passes superficial to the (blank) ligament, and enters the perineum passing deep to the (blank) ligament

Answer 22

sacrospinous; sacrotuberous

Question 23

Once in the ischioanal fossa, the pudendal nerve gives off the (blank) and then enters the pudendal canal to travel anteriorly towards the UG triangle.

Answer 23

inferior rectals

Question 24

The pudendal nerve supplies (blank) innervation to the external sphincter and UG triangle muscles, and (blank) innervation to the perineum.

Answer 24

motor; sensory

Question 25

The internal pudendal artery and vein follow the (blank) into the canal giving off similar branches.

Answer 25

pudendal nerve

Question 26

Rectum is approximately 10 cm in length and begins at the (blank) vertebra and extends to the (blank).

Answer 26

S3; rectoanal junction

Question 27

Where does the anal canal begin? Where does it end?

Answer 27

At the superior limit of the pelvic diaphragm-where the rectal ampulla narrows; anus

Question 28

The pectinate line marks the point where (blank) motor and sensory above give way to (blank) motor and sensory below

Answer 28

viscero; somatic

Question 29

The pectinate line is also the point of junction between the embryonic (blank) and the proctodeum.

Answer 29

hindgut

Question 30

``` Three blood supplies to the anal canal Which vessel(s) are a branch of the IMA? Which vessel(s) are a branch of the common iliacs? ```

Answer 30

superior, middle, and inferior rectals Superior rectal from the IMA Middle and inferior from the pectinate, which comes off of the common iliacs

Question 31

Three vessels drain the anal canal with anastomoses, two return to the (blank) and one to the (blank). What can portal hypertension cause?

Answer 31

systemic; portal; varices in the venous plexuses

Question 32

Above the pectinate line, where do lymph nodes drain? Below the pectinate line, where do lymph nodes drain? Where does all of the lymph ultimately go?

Answer 32

iliac nodes; inguinal nodes; cysterna chyli and thoracic duct

Question 33

What nerves supply the anal canal above the pectinate line?

Answer 33

hypogastric plexus

Question 34

What maintains the tone of the internal sphincter? What inhibits tone and evokes peristalsis?

Answer 34

sympathetics; parasympathetics

Question 35

Above the pectinate line, where do afferents to the spinal cord travel? Below the pectinate line?

Answer 35

S2-4 pelvic splanchnics; inferior rectal nerves

Question 36

Below the pectinate line, afferent nerves are somatosensory. What does this mean?

Answer 36

They are sensitive to all normal stimuli

Question 37

This muscle serves an important function in preventing untimely flatulence and defecation during relaxation of the involuntary internal anal sphincter

Answer 37

puborectalis

Question 38

What innervates the external anal sphincter?

Answer 38

inferior rectals off of the pudendal (S2-4)

Question 39

What innervates the levator ani?

Answer 39

small branches off the sacral plexus (S4) and some from the inferior rectal

Question 40

The UG triangle extends from the ischial tuberosities to the (blank) and is filled in by the (blank).

Answer 40

pubis; UG diaphragm

Question 41

Does the urethra pass through the UG triangle? What else passes through in the female? What is contained in the UG triangle?

Answer 41

yes; vagina; muscles and erectile tissues of the external genitalia

Question 42

Two muscles of the UG diaphragm in males

Answer 42

deep transverse perineal | sphincter urethrae

Question 43

The two muscles of the UG diaphragm are encased above and below by a dense connective tissue envelope-the superior and inferior fascia. The inferior fascia is very thick and is referred to as...?

Answer 43

perineal membrane

Question 44

The perineal membrane serves as the major attachment site of the (blank)

Answer 44

external genitalia

Question 45

These glands are located in the UG diaphragm. The ducts of the glands enter the urethra more superiorly.

Answer 45

bulbourethral glands

Question 46

Discuss the barriers of the "deep pouch"

Answer 46

extends superiorly from the perineal membrane to the investing fascia of the pelvic diaphragm

Question 47

What are the equivalent glands in the female to the bulbourethral gland? Where are these glands located? Where do they drain to?

Answer 47

Bartholin's glands; located entirely within the superficial pouch; drain to vagina

Question 48

What are the three bodies of erectile tissue attached to the perineal membrane?

Answer 48

two crura laterally and one midline bulb housing the urethra

Question 49

What covers the erectile tissues directly? What then covers the deep layer, and binds the tissues together to form the penis?

Answer 49

dense CT called tunica albuginea; deep perineal fascia (Buck's fascia)

Question 50

mushroom shaped cap of erectile tissue covered over by foreskin in the uncircumcised male.

Answer 50

glans

Question 51

This surrounds the corpus spongiosum of the penis

Answer 51

corpus cavernosum

Question 52

What do the crura of the penis become?

Answer 52

corpora cavernosa

Question 53

What does the bulb of the penis become?

Answer 53

corpus spongiosum

Question 54

What layer of fascia is continuous with the deep perineal fascia? What layer of fascia lines the scrotum and ultimately blends with the membranous layer of the abdominal wall?

Answer 54

Buck's fascia; Dartos fascia

Question 55

In the female external genitalia, the bulb is split into two and is separated by the vestibule of the vagina. It does not contribute to the formation of the (blank)

Answer 55

clitoris

Question 56

What forms the glans of the clitoris?

Answer 56

extensions of the crura on either side

Question 57

The female external genitalia are contained in a dense connective tissue called the (blank)

Answer 57

tunica albuginea

Question 58

Two muscles of superficial perineal pouch

Answer 58

bulbospongiosus | ischiocavernosus

Question 59

In males, what are the two muscles of the external genitalia? What covers all three muscles? This layer is continuous with the investing fascia of the anterior abdominal wall muscles.

Answer 59

bulbospongiosus ischiocavernosus deep perineal fascia called Gallaudet's (same as Buck's on the penis)

Question 60

Nerves of the perineum: After the pudendal gives off the inferior rectals, it gives off (blank) branches to the muscles, (blank) branches to the skin, and the (blank) nerve to the penis.

Answer 60

deep perineal; superficial perineal; dorsal nerve

Question 61

This nerve is entirely sensory to the penis

Answer 61

dorsal nerve

Question 62

Blood flow to the perineum is similar to nerve supply, with the addition of two arteries.

Answer 62

An artery to the bulb and one deep artery running through each crura of the penis

Question 63

The internal pudendal artery gives off (blank) branches, an artery to the (blank), a (blank) artery to each crura and the (blank) artery of the penis

Answer 63

perineal; bulb; deep; dorsal

Question 64

Venous return is similar to arterial flow with one exception

Answer 64

dorsal vein of the penis drains to the prostatic plexus no the internal pudendal vein

Question 65

T/F: The pudendal nerve in the female follows the exact pattern as that in the male

Answer 65

True

Question 66

T/F: The arterial supply and venous draining in the female is identical to that in the male

Answer 66

True

Question 67

Internal pudendal artery first gives off inferior rectal artery, then (blank) branches, then an artery to the (blank), (blank) arteries to the crura, and a (blank) artery of the clitoris.

Answer 67

perineal; bulb; deep; dorsal

Question 68

This fascia replaces the fatty layer and has smooth muscle in the scrotum

Answer 68

Dartos fascia

Question 69

This fascia is the membranous layer of the superficial fascia

Answer 69

Colles' fascia

Question 70

This is an investing layer on the penis and is continuous with Gallaudet's over the muscles of the genitalia and the UG diaphragm

Answer 70

Buck's fascia

Question 71

(blank) fascial layers extend into the anal triangle, but the (blank) fascial layers stop at the posterior border of U-G diaphragm. Both stop at the (blank).

Answer 71

superficial; deep; fascia lata

Question 72

The (blank) of the vagina is the space between the labia minora. What openings does it contain?

Answer 72

vestibule; urethra, vagina, and greater and lesser vestibular glands

Question 73

This is the area of skin that overlies the pubic symphysis

Answer 73

mons pubis

Question 74

Empty into the urethral orifice and secrete a watery fluid similar to that secreted by the prostate

Answer 74

Paraurethral (Skene's) glands

Question 75

Three components of the male urethra

Answer 75

``` prostatic urethra (runs through prostate gland) membranous urethra spongy urethra (longest and lengthiest portion) ```

Question 76

The pelvic cavity of the true pelvis has the pelvic floor as its inferior border. The perineum has the pelvic floor as its superior border. Some sources do not consider "pelvic floor" and "pelvic diaphragm" to be identical, with the "diaphragm" consisting of only the levator ani and coccygeus, while the "floor" also includes the perineal membrane and deep perineal pouch.[2] However, other sources include the fascia as part of the diaphragm.[3] In practice, the two terms are often used interchangeably.

Answer 76

Yep.