4.b) Pelvis

Question 1

What type of joint in the sacroiliac joint?

Answer 1

Synovial joint

Question 2

What type of joint is the pubic symphysis?

Answer 2

Secondary cartilaginous joint

Question 3

What is the name of the surface that articulates with the head of the femur?

Answer 3

Acetabular fossa

Question 4

What is considered the ‘true pelvis’?

Answer 4

Within the pelvic inlet.

Question 5

What constitutes the pelvic wall?

Answer 5

Sacrum
Coccyx
Pelvic bones

Question 6

What are the 2 main ligaments in the true pelvis?

Answer 6

Sacrospinous (sacrum to the ischial spine)

Sacrotuberous (sacrum to the ischial tuberosity)

Question 7

Describe the orientation of the pelvic cavity.

Answer 7

Axis of the pelvic cavity is at a 45 degree angle to the axis of the abdominal cavity
Antero-inferiorly inclined

Question 8

Shape of pelvic cavity

Answer 8

Conical/ cylindrical

Question 9

Which muscle lines most of the pelvic bone facing the pelvic cavity?

Answer 9

Obturator internus

Question 10

Where does the obturator internus insert and what other muscle inserts here?

Answer 10

Medial surface of the greater trochanter of the femur

Piriformis also inserts here

Question 11

What muscle overlays the sacrospinous ligament?

Answer 11

Coccygeus muscle

Question 12

What are the 3 main muscles of the pelvic floor and what are they called collectively?

Answer 12

Iliococcygeus muscle
Pubococcygeus muscle
Puborectalis muscle
These muscles make up Levator Ani

Question 13

What forms the border between the obturator internus and the levator ani?

Answer 13

Tendinous arch of obturator internus fascia

Question 14

What other ligament is found adjacent to Levantor Ani muscle?

Answer 14

Anococcygeal ligament

Question 15

What does the pelvic diaphragm consists of?

Answer 15

Bowl like pair of skeletal muscles (Levantor Ani)

Support pelvic organs

Question 16

What is the nerve supply to the levator ani?

Answer 16

Pudendal nerve (S2-S4) and directly from S4

Question 17

What are the openings in the levator ani?

Answer 17

Urethra
Vagina
Anal canal

Question 18

What is the perineal membrane?

Answer 18

Inferior layer of the fascia of the urogenital part of pelvic diaphragm

Question 19

What does the perineum contain?

Answer 19

Voluntary sphincters

External genitalia

Question 20

What is the name of the fat-filled space between the levator ani and the obturator internus in a male?

Answer 20

Ischio-anal fossa

Question 21

What are the 2 sphincters in the urethra of a male?

Answer 21

Internal urethral sphincter (Smooth muscle)

External urethral sphincter (Skeletal muscle)

Question 22

What are the 4 parts of the male urethra? How long is it?

Answer 22

Preprostatic
Prostatic
Membranous
Spongy 
20 cm

Question 23

Describe the arrangement of the uterus and the bladder in women.

Answer 23

The uterus sits on top of the bladder

Question 24

What is different about the urethral sphincters in women?

Answer 24

Women have a poorly organised internal sphincter.

External urethral sphincter is skeletal muscle surrounding the urethra in the deep perineal pouch.

Question 25

Where is the external urethral sphincter of women found?

Answer 25

In the deep perineal pouch

Question 26

How long is the female urethra and vagina?

Answer 26

Urethra: 4 cm
Vagina: 8-12 cm

Question 27

What are 2 additional groups of muscle found in females?

Answer 27

Sphinter urethrovaginalis

Compressor urethrae

Question 28

Describe the shape of an empty bladder.

Answer 28

Tetrahedral

Question 29

What are the structures are each corner of the tetrahedron of the bladder?

Answer 29

Posterior superior vertices: ureters enter
Anterior vertex: has the median umbilical ligament
Posterior inferior vertex: urethra exits

Question 30

What covers the superior surface of the bladder?

Answer 30

Peritoneum

Question 31

Where does the bladder expand?

Answer 31

Between transversals fascia and lining peritoneum

Question 32

Describe the 2 sphincters of the bladders

Answer 32

Smooth muscle sphincter (vesicae) at neck

Skeletal muscle sphincter (urethrae) in perineum

Question 33

Describe the structure of the rectum.

Answer 33

It has a double S bend.
There are 3 transverse rectal folds (superior, middle and inferior).
Keeps the load off the sphincter.

Question 34

What vessels supply the rectum?

Answer 34

Superior, middle and inferior rectal arteries

Question 35

Which nerves supply the rectum and which nerves supply the anal canal?

Answer 35

Rectum: autonomic nerves (Sensitive to filling)

Anal canal: somatic nerves (V. sensitive to injury)

Question 36

Which muscle is most important for faecal continence and what does it do?

Answer 36

Puborectalis part of Levantor Ani muscle: it puts a sharp angle into the recto-anal junction.

Question 37

What could badly injure the Puborectalis muscle?

Answer 37

Episiotomy

Question 38

Describe the muscle types in the internal and external anal sphincters

Answer 38

Smooth muscle (internal)
skeletal muscle (external)

Question 39

Where is the “right-angle bend back” in the rectum/ anus?

Answer 39

Recto-anal junction

Question 40

What main blood vessels supply all the pelvic organs? (except the ovaries)

Answer 40

Internal iliac artery

Question 41

What constitutes the margin of the pelvic inlet?

Answer 41

Pubic symphysis
Pecten pubis
Arcuate line
Ala of sacrum
Body of sacrum

Question 42

What constitutes the margin of the pelvic outlet?

Answer 42

Inferior pubic symphysis
Pubic arches
Sacrotuberous ligament
Coccyx

Question 43

What are the anterior and posterior vertices of the wedge shaped true pelvis?

Answer 43

Sacral promontory to upper border of pubic symphysis

Lower border of pubic symphysis to coccyx