Pelvis

Question 1

most common cause of death in LC fractures

Answer 1

closed head injury

Question 2

most common cause of death in APC fractures

Answer 2

combined pelvic/visceral injury

Question 3

where does common iliac system begin?

Answer 3

L4, near bifurcation of aorta

Question 4

course of external iliac

Answer 4

courses anteriorly along pelvic brim and emerges as the common femoral artery distal to the inguinal ligament

Question 5

course of internal iliac

Answer 5

dives posteriorly near SI joint, divides into posterior division (giving off superior gluteal artery) and anterior division (giving off obturator artery)

Question 6

what is the corona mortis?

Answer 6

anastamosis between internal iliac (obturator) and external iliac (epigastric) systems

Question 7

what structures are involved in an APC injury?

Answer 7

pubic symphysis, pelvic ligaments

Question 8

what structures are involved in a LC injury?

Answer 8

rami, ala, ilium

Question 9

what type of pelvic fracture is a/w the highest risk of hypovolemic shock?

Answer 9

vertical shear

Question 10

what is the most common source of bleeding in a pelvic fracture?

Answer 10

posterior venous plexus

Question 11

what are the landmarks in placing a pelvic binder?

Answer 11

center over greater trochanters

Question 12

tearing of which ligaments differentiates APC II from APC III?

Answer 12

posterior sacroiliac ligaments

Question 13

what is a crescent fracture?

Answer 13

SI fracture dislocation (iliac wing fracture enters SI joint)

Question 14

how do you test S1?

Answer 14

plantarflexion (gastroc/soleus)

Question 15

how do you test L5?

Answer 15

big toe extension (EHL)

Question 16

how do you test L4?

Answer 16

ankle dorsiflexion (tib ant)

Question 17

what radiographic view shows A-P placement of a percutaneous iliosacral screw?

Answer 17

inlet view

Question 18

what’s the most important factor in predicting outcomes in sacral fractures?

Answer 18

presence of neuro deficit

Question 19

what neuro structure runs on top of the sacral ala?

Answer 19

L5 nerve root

Question 20

how do you classify sacral fractures?

Answer 20

Denis classification

Question 21

how do you classify pelvic fractures?

Answer 21

Burgess-Young classification

Question 22

what is a zone 1 denis fracture?

Answer 22

sacral fracture lateral to sacral foramina

Question 23

what is a zone 2 denis fracture?

Answer 23

sacral fracture through sacral foramina

Question 24

what is a zone 3 denis fracture?

Answer 24

sacral fracture medial to sacral foramina

Question 25

what are the elementary acetabular fractures?

Answer 25

posterior wall, posterior column, anterior wall, anterior column, transverse

Question 26

what are the associated acetabular fractures?

Answer 26

associated both column, transverse + posterior wall, T-shaped, anterior column or wall + posterior hemitransverse, posterior column + posterior wall

Question 27

what does the “gull sign” indicate?

Answer 27

posterior wall acetabular fracture

Question 28

what does the “spur sign” indicate?

Answer 28

associated both column acetabular fracture

Question 29

what structures are at risk with the anterior/ilioinguinal approach to the acetabulum?

Answer 29

femoral nerve, lateral femoral cutaneous nerve, corona mortis

Question 30

what structures are at risk with the posterior/Kocher-Langenbach approach to the acetabulum?

Answer 30

sciatic nerve, medial femoral circumflex (blood supply to femoral head)

Question 31

how do you reduce tension on the sciatic nerve during a posterior approach?

Answer 31

flex knee and extend hip