B6.070 Large Group MSK Imaging

Question 1

describe key features of the iliac bone

Answer 1

iliac crest - abdominal muscle attachments
anterior superior iliac spine - origin of sartorius and tensor fascia lata
anterior inferior iliac spine - origin of straight head of rectus femoris

Question 2

sacral foramen

Answer 2

sacral nerve foots travel through here

Question 3

ischial tuberosity

Answer 3

origin of hamstring tendons

Question 4

pubic bone

Answer 4

origin of adductors

Question 5

what is the significance of the pelvis being 3 rings

Answer 5

hard to break a ring in only one place…look around for multiple fractures

Question 6

ileopectineal line

Answer 6

traces lower quadrant of the major pelvic circle

Question 7

obturator ring

Answer 7

traces small rings below the main ring of the pelvis

Question 8

Shenton’s arc

Answer 8

continuous line from lower line of the femoral neck through the top of the obturator ring on the same size (should line up)

Question 9

3 main types of fractures at femoral head/neck

Answer 9

subcapital
transcervical (neck)
intertrochanteric

Question 10

avascular necrosis of the femoral head

Answer 10

blood supply to femoral head runs through femoral neck

risk of avascular necrosis of femoral head increases with degree of displacement of fracture

Question 11

initial study for suspected hip fracture

Answer 11

pelvic radiographs

Question 12

choice of study for suspected, radiographically occult hip fracture

Answer 12

pelvic MRI

Question 13

why would you image a diabetic foot wound?

Answer 13

to determine the presence of osteomyelitis

Question 14

initial study for diabetic foot wound

Answer 14

xray and MRI both 9 on ACR criteria

Question 15

key finding in xray of diabetic foot

Answer 15

atherosclerotic calcification of small vessel of the foot

Question 16

T1 coloration

Answer 16

fat and contrast appear bright

Question 17

T2 coloration

Answer 17

water is bright

edema = increased water content

Question 18

how to determine hyperemia on T1 sequence

Answer 18

fat suppressed view

can see where contrast accumulates in pt

Question 19

annual rate of foot ulcers in diabetics

Answer 19

2-5%

Question 20

what % of non traumatic LE amputations are in diabetics

Answer 20

40-60%

Question 21

what % of diabetic amputations are preceded by foot ulcers

Answer 21

85%

Question 22

etiology of diabetic foot wounds

Answer 22

neuropathy: altered weight bearing in foot and development of pressure ulcers, increased risk of trauma due to loss of protective sensation
vasculopathy: decreased blood flow to affected tissue and decreased delivery of leukocytes and Abx
increased serum blood glucose: impaired action of neutrophils

Question 23

ttx of diabetic foot wounds

Answer 23

oral Abx and limited debridement for limited cellulitis

extended IV antibiotics and amputations in advanced disease

Question 24

key bone findings of diabetic foot wounds on xray

Answer 24

irregularity of cortical bone and periostitis

gross destruction of the cortical and underlying trabecular bone

Question 25

MRI findings of osteomyelitis

Answer 25

LOW T1 and HIGH T2 intensity

increased bony enhancement on post contrast T1 image