2 - Acute osteomyelitis

Question 1

bone infection?

Answer 1

osteomyelitis

Question 2

joint infection?

Answer 2

septic arthritis

Question 3

what type of osteomyelitis is more common?

Answer 3

non-specific

Question 4

give 4 RFs for acute osteomyelitis?

Answer 4

children, M, history of minor trauma, other disease (e.g. diabetes)

Question 5

3 general sources of infection in acute osteomyelitis?

Answer 5

haematogenous spread (children and elderly), local spread from trauma, 2y to vascular insufficiency

Question 6

main route of infection for acute osteomyelitis in infants?

Answer 6

infected umbilical cord

Question 7

3 main routes of infection for acute osteomyelitis in children?

Answer 7

boils, tonsilitis, skin abrasions

Question 8

2 main routes of infection for acute osteomyelitis in adults?

Answer 8

UTI, arterial line

Question 9

3 organisms causing acute osteomyelitis in infants <1 yr?

Answer 9

staph aureus, group B streptococci, E. coli

Question 10

3 organisms causing acute osteomyelitis in older children?

Answer 10

staph aureus, strep pyogenes, haemophilus influenzae

Question 11

main causative organism of acute osteomyelitis in adults?

Answer 11

staph aureus

Question 12

main causative organism of acute osteomyelitis in adults with diabetic foot/ pressure sores?

Answer 12

mixed infection including anaerobes

Question 13

main causative organism of acute osteomyelitis in adults with sickle cell disease?

Answer 13

salmonella spp

Question 14

main causative organism of acute osteomyelitis in fishermen?

Answer 14

mycobacterium marinum

Question 15

main causative organism of acute osteomyelitis in adults with HIV AIDS/ debilitating illness?

Answer 15

candida

Question 16

pathology of acute osteomyelitis - 3 locations of metaphysis in long bones?

Answer 16

distal femur, proximal tibia, proximal humerus

Question 17

pathology of acute osteomyelitis - 2 locations of metaphysis in joints?

Answer 17

hip, elbow

Question 18

first 3 stages of pathology of acute osteomyelitis?

Answer 18

metaphysis trauma, vascular stasis, acute inflammation

Question 19

4 later stages of pathology of acute osteomyelitis which leads to recovery?

Answer 19

release of pressure, necrosis of bone, new bone formation, resolution

Question 20

what happens if acute osteomyelitis is not resolved?

Answer 20

chronic osteomyelitis

Question 21

4 clinical features in infant?

Answer 21

minimal signs - failure to thrive, drowsy/irritable, swelling (usually at knee), positional change

Question 22

4 clinical features in child?

Answer 22

severe pain, reluctant to move, tender fever, tachycardia

Question 23

4 clinical features of 1y acute OM in adult?

Answer 23

thoracolumbar spine, backache, UTI history, diabetic (immunocompromised)

Question 24

when is 2y acute OM seen?

Answer 24

after open fracture, surgery (ORIF)

Question 25

diagnosis of acute OM?

Answer 25

3 blood cultures - @ peak temperature 60% +ve

Question 26

other tests to diagnose acute OM?

Answer 26

FBC & WBC (neutrophil leucocytosis), ESR, CRP, U&Es

Question 27

4 common differentials for acute OM?

Answer 27

acute septic arthritis, acute inflammatory arthritis, | trauma, transient synovitis

Question 28

4 rare differentials for acute OM?

Answer 28

sickle cell crisis, Gaucher’s disease, rheumatic fever, haemophilia

Question 29

4 soft tissue infection differentials for acute OM?

Answer 29

cellulitis, erysipelas, necrotising fasciitis, gas gangrene

Question 30

3 imaging tests for acute OM?

Answer 30

X-ray - normal in the first 10-14 days, US, isotope Bone scan

Question 31

what is used in the isotope bone scan?

Answer 31

Tc-99, Gallium-67

Question 32

when do periosteal changes occur on radiographs?

Answer 32

10-20 days

Question 33

what changes occur at the lytic areas?

Answer 33

medullary changes

Question 34

late osteonecrosis?

Answer 34

sequestrum

Question 35

late periosteal new bone?

Answer 35

involucrum

Question 36

3 microbiological diagnosis?

Answer 36

blood cultures, bone biopsy, tissue from up to 5 sites around implant

Question 37

treatment for acute OM?

Answer 37

supportive treatment, rest & splintage, antibiotics, surgery

Question 38

supportive treatment?

Answer 38

analgesia, IV fluids, etc.

Question 39

route of antibiotics?

Answer 39

IV/ oral

Question 40

duration of antibiotics?

Answer 40

4-6 weeks

Question 41

type of antibiotics?

Answer 41

empirical - fluclox and benzylpen

Question 42

3 reasons antibiotics fail to work?

Answer 42

drug resistance, poor tissue penetration, poor drug absorption

Question 43

name 4 complications of acute OM?

Answer 43

septicemia, metastatic infection, septic arthritis, altered bone growth