MSK

Question 1

What features present on a plain X-ray indicate osteomyelitis?

Answer 1

cortical erosion
periosteal reaction
mixed lucency 
sclerosis
sequestra 
soft tissue swelling

Question 2

What are the advantages of using MRI scans over plain radiographs when diagnosing osteomyelitis?

Answer 2

shows marrow oedema in 3 days

delineates cortical, bone marrow and soft tissue inflammation

Question 3

What are the differential diagnoses for osteomyelitis?

Answer 3

soft tissue infection (cellulitis and erysipelas)
charcot joint (neuropathic arthropathy- progressive degen of weight-bearing joint)
avascular necrosis of bone due to radiation, steroid or bisphosphonate use
gout
fracture
bursitis
malignancy