Pelvis and Perineum

Question 1

What are the functions of the bony pelvis?

Answer 1

• Protect the abdominal and pelvic viscera
• Transfers body weight
• Withstands compression
• Serves as attachment point for muscles

Question 2

When do the ilium, ischium and pubis fuse?

Answer 2

puberty

Question 3

Review bony landmarks of pelvis

Answer 3

pg. 1

Question 4

What is the fibrocartilage connection connecting pubis bones called?

Answer 4

pubic symphysis

Question 5

What is the pubic arched formed by?

Answer 5

inferior pubic rami and ischial rami from both sides

Question 6

T/F: ASIS and pubic symphysis are in the same horizontal plane

Answer 6

False, they re in the same vertical plane

Question 7

Which structure is open to the abdominal cavity?

Answer 7

pelvic inlet

Question 8

What does the pelvic brim consist of?

Answer 8

sacral promontory and ala, ilial arcuate line, superior pubic ramus, and pubic symphysis

Question 9

How is the pelvic outlet closed off?

Answer 9

by the funnel-shaped pelvic diaphragm

Question 10

What is the pelvic outlet bounded by?

Answer 10

pubic arch, ischial tuberosities, sacrotuberous lig., tip of coccyx

Question 11

Which pelvis (greater or lesser) is also known as the false pelvis, and which is the true pelvis?

Answer 11

greater = false
lesser = true

Question 12

Which pelvis (greater or lesser) contains some abdominal contents?

Answer 12

greater/false

Question 13

Which structure is contained between the pelvic inlet and pelvic outlet?

Answer 13

lesser pelvis

Question 14

What are the differences between male and female pelvic bones?

Answer 14

Male = 60 degree subpubic angle, thicker, heavier, narrow/deep lesser pelvis

Female= 90 degree subpubic angle, wide/shallow and larger pelvic inlet/outet, round or oval pelvic inlet

Question 15

Which type of compression causes fractures to pubic rami?

Answer 15

anteroposterior compression

Question 16

Which type of compression causes fractures to acetabula and ilia?

Answer 16

lateral compression

Question 17

Can a pelvic ligament cause a fracture?

Answer 17

yes, as it is torn away from the bone

Question 18

What type of joint is located posteriorly between tuberosities of sacroiliac bones?

Answer 18

syndesmosis

Question 19

What type of joint is located anteriorly between auricular surfaces of sacroiliac bones?

Answer 19

synovial joint

Question 20

What ligament is the thin anterior part of capsule called?

Answer 20

anterior sacroiliac lig.

Question 21

What are the features of the interosseous sacroiliac lig.?

Answer 21

broad, fibrous connections between tuberosities - primarily responsible for weight transfer

Question 22

What direction are the fibers of the posterior sacroiliac lig. oriented?

Answer 22

obliquely, superolaterally

Question 23

What are the functions of the sacrotuberous and sacrospinous ligaments?

Answer 23

• limit upward mvmt of inferior part of sacrum

- resist sacral rotational mvmt during periods of sudden weight gain

Question 24

Which direction are the facet joints in the lumbosacral joint oriented?

Answer 24

posteromedially, which helps L5 from sliding anteriorly

Question 25

Is the fibrocartilagenous disc of the pubic symphysis thicker in males or females?

Answer 25

females

Question 26

How much (in %) does the pelvic diameter increase during parturition?

Answer 26

10-15%, change is in transverse axis and NOT A-P

Question 27

What primarily closes the obturator foramen?

Answer 27

Obturator membrane

Question 28

Which foramen does the obturator internus m. travel through to reach the greater trochanter?

Answer 28

lesser sciatic foramen

Question 29

What is the action of the obturator internus?

Answer 29

lateral rotation, hold head of femur in acetabulum

Question 30

Which foramen does the piriformis m. exit the pelvis by?

Answer 30

greater sciatic foramen

Question 31

The nerves of the sacral plexus cross the _________ (internal or external) surface of this muscle

Answer 31

internal

Question 32

What is the action of the piriformis m.?

Answer 32

lateral rotation and abduction, and holds femur in acetabulum

Question 33

What muscle groups form the pelvic diaphragm?

Answer 33

levator ani mm. and coccygeus m.

Question 34

What is the function of the levator ani m.?

Answer 34

forms a muscular sling to support abdominopelvic viscera and resists increases in intra-abdominal pressure

Question 35

what is the action (not function) of the levator ani m.?

Answer 35

raises pelvic floor and compresses abdominopelvic contents

Question 36

Which muscle forms the narrow medial part of levator ani mm. ?

Answer 36

puborectalis m.

Question 37

What does the puborectalis m. form, surround, and create?

Answer 37

- forms a U-shaped sling around anorectal junction - surrounds the urogenital hiatus - creates the puborectal sling at anorectal junction- the anorectal flexure

Question 38

What is the main intermediate part of the levator ani m.?

Answer 38

pubococcygeus m.

Question 39

Which levator ani m. is thin and aponeurotic?

Answer 39

iliococcygeus m.

Question 40

Which ligament does the coccygeus m. lie across?

Answer 40

pelvic surface of the sacrospinous lig.

Question 41

What is the innervation of the coccygeus?

Answer 41

VPR of S4-S5

Question 42

What are the differences between parietal and visceral pelvic fascia?

Answer 42

``` parietal = membranous overlying muscles visceral = adventitial ensheathing pelvic organs ```

Question 43

What makes up the tendinous arch of pelvic fascia in males?

Answer 43

puboprostatic and sacrogenital ligs.

Question 44

What makes up the tendinous arch of pelvic fascia in females?

Answer 44

pubovesical and uterosacral ligs.

Question 45

What separates the pelvic cavity from the perineum?

Answer 45

pelvic diaphragm

Question 46

What are the general borders of the perineum?

Answer 46

``` mons pubis (anteriorly) medial surfaces of proximal thigh (laterally) gluteal fold and intergluteal cleft (posteriorly) ```

Question 47

Which anatomical triangle contains the external genitalia?

Answer 47

urogenital triangle

Question 48

what covers the urogenital triangle, spanning the pubic arch?

Answer 48

perineal membrane

Question 49

What structures perforate through the urogenital triangle?

Answer 49

urethra (in both sexes) and the vagina (in females)

Question 50

What is the central point of the perineum called?

Answer 50

perineal body, post to vag and ant to anus

Question 51

Which muscles attach to the perineal body?

Answer 51

- superficial transverse perineal m. - deep transverse perineal m. - external anal sphincter - bulbospongiosus

Question 52

How could damage to the perineal body affect females?

Answer 52

prolapse of the vagiinnnee