Muscles of the pelvis

Question 1

what muscles line the lateral pelvic walls

where do they attach

Answer 1

obturator interns and pirifromis

greater trochanter of femur

Question 2

what muscles form the pelvic diaphragm

Answer 2

levator ani and coccygeus

Question 3

what muscles form the levator ani

Answer 3

pubococcygeus
puborectalis
iliococcygeus

Question 4

function of obturator internus

Answer 4

rotates extended thigh laterally - abducts flexed thigh at hip

Question 5

function of piriformis

Answer 5

rotates extended thigh laterally and abducts flexed thigh and stabilises hip joint

Question 6

functions of levator ani muscles

Answer 6

supports pelvic viscera

raises pelvic floor

Question 7

function of coccygeus

Answer 7

supports pelvic viscera and draws the coccyx forward

Question 8

innervation of levator ani muscles

Answer 8

anterior rami of S3-S4 perineal nerve of the pudendal nerve

Question 9

innervation of coccygeus

Answer 9

anterior rami of S4-S5

Question 10

if the levator ani muscles are injured what two clinical conditions can occur

Answer 10

urinary and fecal incontince and prolapsed the uterus

Question 11

the normal angle between the rectum and anal canal is 90 degrees but during defecation when the anal canal wings forward what does this angle change to

Answer 11

40-50 degrees

relaxation of the muscles and anal sphincter opens the anal canal