Walls and Floor of Pelvis

Question 1

What divides the greater and lesser sciatic foramen?

Answer 1

sacrospinous and sacrotuberous ligaments

Question 2

What muscle makes up the side wall of the pelvis?

Answer 2

obturator internus

Question 3

What muscle makes up the posterior wall of the pelvis?

Answer 3

piriformis

Question 4

What is the origin and insertion of obturator internus?

Answer 4

originates from the obturator membrane and the surrounding obturator foramen and inserts on to the medial aspect of the greater trochanter

Question 5

What is the origin and insertion of piriformis?

Answer 5

originates from the middle 3 bodies of the sacrum and the adjacent parts of the lateral mass and inserts on the greater trochanter

Question 6

What are the three components of the pelvic floor?

Answer 6

pubococcygeus, iliococcygeus and ischiococcygeus

Question 7

What makes up levator ani?

Answer 7

pubococcygeus and iliococcygeus

Question 8

What is the origin of the muscles of the pelvic floor?

Answer 8

the internal aspect of the pubic bone, fascial thickening halfway up obturator internus and the ischial spine

Question 9

What is the insertion of the muscles of the pelvic floor?

Answer 9

midline raphe from the tip of the coccyx to the anorectal junction

Question 10

What are pubovaginalis, puboprostaticus and puborectalis?

Answer 10

muscular slings formed by the most anterior fibres of pubococcygeus that sling around the midline viscera

Question 11

What is the action of levator ani?

Answer 11

to elevate the pelvic floor

Question 12

What is the action of ischiococcygeus?

Answer 12

no function in humans - in animals it wags their tail

Question 13

What is the anorectal angle?

Answer 13

an angle of 80 degrees that kinks the anorectal juntion - formed by puborectalis - important in fecal continence

Question 14

What is covered by dense fascia in the pelvis?

Answer 14

things that dont need to expand - walls of the pelvis and rigid structures e.g. prostate

Question 15

What is covered by loose fascia in the pelvis?

Answer 15

on things that need to expand - levator ani, bladder, anus

Question 16

What is endopelvic fascia?

Answer 16

the fascia that fills the spaces in the pelvis

Question 17

Where is the sacral plexus in relation to piriformis and the deep fascia?

Answer 17

the sacral plexus is between piriformis and the deep fascia

Question 18

Where does the common iliac artery divide?

Answer 18

at the top of the pelvic brim

Question 19

What does the posterior division of the internal iliac supply?

Answer 19

only has parietal branches - so supplies the walls of the pelvis

Question 20

What does the anterior division of the internal iliac supply?

Answer 20

has parietal and visceral branches so supplies both the walls of the pelvis and the viscera

Question 21

What divides the pelvic viscera from the abdominal cavity?

Answer 21

the pelvic peritoneum

Question 22

What is the vesicouterine pouch?

Answer 22

the pouch created by the fold of pelvic peritoneum between the bladder and the superior anterior part of the uterus

Question 23

What is the pouch of douglas?

Answer 23

the pouch created by the fold of pelvic peritoneum between the posterior part of the uterus, the posterior superior part of the vagina and the rectum

Question 24

Why does free fluid collect in the pouch of douglas?

Answer 24

because its the lowest point of the abdomen

Question 25

How can a backyard abortion cause peritoneal sepsis?

Answer 25

if the unsterilised instruments puncture the posterior superior part of the vagina it has direct access to the abdominal cavity via the pouch of douglas