Introduction to the Pelvis and Perineum; Anal Triangle | B2 WK4

Question 1

What are the 3 bones of the os coxae?

Answer 1

1. Ilium
2. Ischium
3. Pubis

Question 2

What separates the true pelvis from the false pelvis?

Answer 2

Pelvic inlet

Question 3

What is inferior to the pelvic inlet and contains pelvic viscera?

Answer 3

True (lesser) pelvis

Question 4

What is superior to the pelvic inlet and contains inferior abdominal viscera?

Answer 4

False (grater) pelvis

Question 5

The linea terminalis, or pelvic brim, consists of what?

Answer 5

1. Pubic crest
2. Pectineal line (pecten pubis)
3. Arcuate line

Question 6

Describe the subpubic angle for a testosterone drive and estrogen-driven pelvis

Answer 6

Testosterone: Smaller angle
Estrogen: wider angle

Question 7

Which pelvis is heart-shaped and has a small pelvic outlet

Answer 7

Testosterone driven

Question 8

Which pelvis is oval-shaped and has a large pelvic outlet

Answer 8

Estrogen Driven

Question 9

The presences of sacrospinous ligament and sacro-tuberous ligament convert the greater & lesser sciatic notch into…

Answer 9

Greater & lesser sciatic foramen

Question 10

What travels through the obturator canal

Answer 10

Obturator Aa + N

Question 11

What ligament helps to prevent sacral flexion?

Answer 11

Sacrotuberous ligament

Question 12

What ligament helps to prevent sacral extension?

Answer 12

Posterior sacroiliac ligament

Question 13

Lumbar plexus

Answer 13

T12, L1-L4

Question 14

Lumbosacral trunk

Answer 14

L4-L5

Question 15

Sacral plexus

Answer 15

S1-S4

Question 16

Coccygeal plexus

Answer 16

S4-Co1

Question 17

The lumbar plexus originates posterior to?

Answer 17

Psoas major m.

Question 18

What are the main nerves of the lumbar plexus?

Answer 18

-Subcostal nerve (T12)
-Iliohypogastric nerve (L1)
-Ilioinguinal nerve (L1)
-Lateral femoral cutaneous nerve (L2-L3)
-Femoral nerve (L2-L4)
-Genitofemoral nerve (L1-L2)
-Obturator nerve (L2-L4)

Question 19

What are the spinal nerves of the sacral plexus?

Answer 19

“SIPP”
1. Superior gluteal N
2. Inferior gluteal N
3. Posterior cutaneous N of thigh (post. cutaneous N)
4. Pudendal N.

Question 20

Voluntary sphincters of pelvis and perineum are controlled by what nerve?

Answer 20

Pudendal N

Question 21

Pelvic splanchnic nerves are…

Answer 21

Parasymphatetic

Question 22

Sacral splanchnic nerves are…

Answer 22

Symphatetic

Question 23

Describe innervation of the urinary bladder

Answer 23

-Autonomic nerves innervate detrusor muscle and internal urethral sphincter
-Somatic nerves innervate the external urethral sphincter (UG diaphragm)

Question 24

Pelvic diaphragm = ________________ + ________________

Answer 24

Levator Ani Muscles + Coccygeus muscles

Question 25

Levator Ani Muscle = ________________ + ________________ + ________________

Answer 25

Puborectalis m
Pubococcygeus m
Iliococcygeus m

Question 26

What muscle relaxes during defication?

Answer 26

Puborectalis

Question 27

What is the perineum?

Answer 27

The area where everything “empties out”

Question 28

What two triangles make the perineum?

Answer 28

1. Urogenital (UG) triangle
2. Anal triangle

Question 29

What are the boundaries of the UG triangle?

Answer 29

-Pubic symphsis
-Ischiopubic rami
-Line connecting ischial tuberosities

Question 30

What are the boundaries of the anal triangle?

Answer 30

-Coccyx
-Sarcotuberous ligament
-Line connecting ischial tuberosities

Question 31

What is the central tendon of the perineum derived from?

Answer 31

Embryological urorectal septum

Question 32

What are the boundaries of the ischioanal fossa?

Answer 32

Lateral: Obturator internus
Medial: External anal sphincter and levator ani
Anterior: line connecting ischial tuberosities
Posterior: Gluteus Maximus

Question 33

Contects of ischioanal fossa

Answer 33

Fat & Inf. rectal vessels and nerves

Question 34

What is the function of the ischioanal fossa?

Answer 34

Permits distension of anal canal dring defecation

Question 35

What is found within the pudendal canal?

Answer 35

-Pudenal Nerve
-Internal pudendal vessels
-N. to obturator internus