Obturator internus/ piriformis

Question 1

Obturator internus origin

Answer 1

margin of pelvic surface of obturator
foramen and membrane

Question 2

Obturator internus insertion

Answer 2

medial surface of greater trochanter

Question 3

Obturator internus innervation

Answer 3

sacral plexus (nerve to
obturator internus and superior
gamellus)

Question 4

Obturator internus blood supply

Answer 4

Internal pudendal and superior
gluteal artery

Question 5

Obturator internus function

Answer 5

lateral rotator of thigh, abducts
thigh when limb is flexed

Question 6

Piriformis origin

Answer 6

anterior surface of sacrum and margin
of greater sciatic foramen and
sacrotuberous ligament

Question 7

Piriformis insertion

Answer 7

superior border of greater trochanter

Question 8

Piriformis innervation

Answer 8

1st and 2nd sacral nerve
(nerve to piriformis)

Question 9

Piriformis blood supply

Answer 9

internal pudendal artery and superior
and inferior gluteal artery

Question 10

Piriformis function

Answer 10

abducts and laterally rotates
thigh