Osteomyelitis

Question 1

What is osteomyelitis?

Answer 1

Infection of the bone

Question 2

What are the 3 routes of infection?

Answer 2

1. Haematogenous e.g. skin, GI, resp
2. Direct inoculation (without poor vascularity) i.e. trauma, surgery
3. Contiguous spread with poor vascularity i.e. diabeti foot infections

Question 3

What is sequestrum?

Answer 3

Devitalised separated bone

Question 4

What is involucrum?

Answer 4

New periosteal bone formation

Question 5

What is cloaca (sinus)?

Answer 5

Site of pus escape

Question 6

What are risk factors in adults?

Answer 6

old age, diabetes, immunosuppression, vascular disease, trauma e.g. surgery

Question 7

What are the most likely causative organisms in adults?

Answer 7

Staph aureus (occasionally strep, enterobacter)
Pseudomonas in IVDUs
Also bartonella, fungal in immunosupression

Question 8

What are the most likely causative organisms in children?

Answer 8

80% staph aureus
also group A strep, h.influenza, enterobacter
Sickle cell anaemia– salmonella

Question 9

How does osteomyelitis present?

Answer 9

Pain, sepsis, effusion of nearby joints, systemic symptoms e.g. fever, weight loss, malaise

Question 10

What investigations should you do for osteomyelitis?

Answer 10

Normal bloods, blood cultures, local cultures (BEFORE antibiotics), x-ray, MRI (gold standard) and biopsy

Question 11

How is osteomyelitis managed?

Answer 11

Resus if acute, analgesia, high dose IV antibiotics (6 weeks if acute to lifelong in chronic), sometimes immobilisation, lifestyle changes e.g. diabetes, physio, sometimes surgery: drainage, removal of sequestrum, debridement of soft tissues, amputation

Question 12

What is the classification system for chronic osteomyelitis?

Answer 12

Cierny-mader classification