Acute Osteomyelitis

Question 1

What is Osteomyelitis

Answer 1

Osteomyelitis (OM) is an infection of bone.

Question 2

What is epidiemiology of osteomyelitis

Answer 2

Mostly children (different ages)
Boys > girls
History of trauma (minor)

Question 3

What are disease associated with ostemyelitis

Answer 3

• diabetes, rheum arthritis, immune compromise, long-term steroid treatment, sickle cell (very specific type)

Question 4

What is the source of infection in infants for osteomyelitis

Answer 4

• Infected umbilical cord

Question 5

What is the source of infection in children for osteomyelitis

Answer 5

• Haematogenous spread
• Boils
• Tonsillitis
• Abrasions

Question 6

What is the source of infection in adults for osteomyelitis

Answer 6

Local spread from contiguous site of infection
Trauma (open fracture), bone surgery (ORIF), joint replacement
Secondary to vascular insufficiency
UTI
Arterial line

Question 7

What is the source of infection in the elderly for osteomyelitis

Answer 7

Haematogenous spread

Question 8

What is the main bacteria that causes osteomyelitis

Answer 8

Staph aureus

Question 9

What are common organisms that cause osteomyelitis in infants

Answer 9

Staph aureus, Group B streptococci, E. coli

Question 10

What are common organisms that cause osteomyelitis in older children

Answer 10

Staph aureus, Strep pyogenes, Haemophilus influenzae

Question 11

What are common organisms that cause osteomyelitis in adults

Answer 11

Staph Aureus

Coagulase negative staphylococci (prostheses),

Propionibacterium

Mycobacterium tuberculosis

Pseudomonas aeroginosa

Question 12

What are some rarer special cases of infection for osteomyelitis

Answer 12

Diabetic foot and Pressure sores - mixed infection including anaerobes
Sickle cell disease – Salmonella spp
Mycobacterium marinum (fishermen, filleters (seal bites)
Candida (debilitating illness, HIV AIDS) – very difficult to eradicate

Question 13

Where do you see acute osteomyelitis?

Answer 13

Long bones

• distal femur
• proximal tibia
• proximal humerus

Joints with intra-articular metaphysis

• hip
• elbow (radial head)

Question 14

What is the pathophysiology of osteomyelitis in long bone

Answer 14

• starts at metaphysis – role of trauma?
• vascular stasis
  o (venous congestion + arterial thrombosis)
• acute inflammation – increased pressure
• suppuration (puss formed)
• release of pressure (rupture of boil/absess)
  o (medulla, sub-periosteal, into joint)
• necrosis of bone (sequestrum) – due to damage to blood supply/the infection
• new bone formation (involucrum)
• resolution - or not (chronic osteomyelitis

Question 15

What are clinical features of osteomyelitis in infants

Answer 15

-	May be minimal signs, or may be very ill
Failure to thrive
-	Poss. drowsy or irritable
-	Metaphyseal tenderness + swelling
-	Decrease ROM 
-	Positional change (eg may be flexed) 
-	Commonest around the knee
-	Often multiple sights

Question 16

What are clinical features of osteomyelitis in children

Answer 16

• Severe pain (will complain)
• Reluctant to move (neighbouring joints held flexed); not weight bearing
• May be tender fever (swinging pyrexia) + tachycardia
• Malaise (fatigue, nausea, vomiting – “nae weel” - fretful
• Toxaemia

Question 17

What are clinical features of primary osteomyelitis in adults

Answer 17

• Primary OM seen commonly in thoracolumbar spine
• Backache and evidence of sepsis
• History of UTI or urological procedure
• Elderly, diabetic, immunocompromised

Question 18

What are clinical features of Secondary osteomyelitis in adults

Answer 18

• Often after open fracture, surgery (esp. ORIF)

- Mixture of organisms

Question 19

What will be elevated in bloods from a patient with osteomyelitis

Answer 19

ESR

CRP

Question 20

When do you take blood cultures from a patient with osteomyelitis

Answer 20

At peak of temperature

Question 21

What investigations should you do for a patient with osteomyelitis

Answer 21

X-ray
Ultrasound
Aspiration
Isotope bone scan 
Labelled white cell scan 
MRI

Question 22

What is to note about xraying for osteomyelitis

Answer 22

normal in the first 10-14 days)
- Early on in infection the organisms breeding in the bone will not show any change until the bone itself has been changed

Question 23

What does an ultrasound look for in osteomyelitis

Answer 23

• Looks for fluid (any ruptured puss)

Question 24

What does isotope bone scan look for and what contrasts are used

Answer 24

• Highlights areas of increased bone turnover

Tc-99, Gallium-67 (contrast

Question 25

What are common(ish) differential diagnosis for osteomyelitis

Answer 25

Acute septic arthritis
Acute inflammatory arthritis
Trauma (fracture, dislocation, etc.)
Transient synovitis (“irritable hip”)

Question 26

What are rare differential diagnosis for osteomyelitis

Answer 26

sickle cell crisis
Gaucher’s disease
rheumatic fever
haemophilia

Question 27

What is treatment for osteomyelitis

Answer 27

Supportive treatment
Antibiotics
Surgery (depending on stage)

Question 28

What antibiotics are given empiracally for osteomyelitis

Answer 28

Empirical (Fluclox + BenzylPen) while waiting as most likely to be staph aureus that causing it.

Question 29

When might a surgical procedure by needed for osteomyelitis

Answer 29

• aspiration of pus for diagnosis & culture
• abscess drainage (multiple drill-holes, primary closure to avoid sinus)
• need to drain otherwise antibiotics cant reach
• debridement of dead/infected /contaminated tissue
• refractory to non-operative Rx >24..48 hrs

Question 30

What are complications of acute osteomyelitis

Answer 30

Septicemia, death
Metastatic infection
Pathological fracture
Septic arthritis
Altered bone growth
Chronic osteomyelitis

Question 31

What is Gaucher disease

Answer 31

Gaucher disease is a rare genetic disorder passed down from parents to children (inherited). When you have Gaucher disease, you are missing an enzyme that breaks down fatty substances called lipids. Lipids start to build up in certain organs such as your spleen and liver.