Osteomyelitis

Question 1

What is osteomyelitis?

Answer 1

Infection of the bone

Question 2

What common organisms cause osteomyelitis?

Answer 2

S.aureus, streptococci species, haemophilus influenzae, pseudomonas aeruginosa, salmonella and Enterobacter species

Question 3

What causes osteomyelitis?

Answer 3

Local spread
Haematogenous spread
Direct inoculation

Question 4

What are the symptoms of osteomyelitis

Answer 4

Low grade fever, malaise, inability to weight bear if lower limb, swollen, red, constantly painful joint worse at night, tender site

Question 5

Which bones are affected more commonly in osteomyelitis?

Answer 5

Adults - vertebrae

Children - long bones

Question 6

Describe the pathophysiology of osteomyelitis

Answer 6

Bacteria use adhesins to bind to host tissue and produce extracellular matrix. Pathogens propagate and spread further in the tissue.
Chronic cases lead to devascularisation of the bone resulting in subsequent necrosis and resorption of bone. Sequestrum - dead pieces of bone are left floating, these can be encapsulated by an involucrum

Question 7

What are the risk factors for osteomyelitis

Answer 7

DM and immunosuppression
IVDU
Alcohol excess

Question 8

What investigations are required for osteomyelitis

Answer 8

Bloods - FBC, ESR, CRP, blood cultures
Imaging - Xray and MRI(definitive diagnosis)
Bone biopsy during debridement (gold standard)

Question 9

What may be seen on radiograph in osteomyelitis

Answer 9

Osteopenia
Periosteal thickening
Focal cortical bone loss
Endosteal scalloping

Question 10

What is the management of osteomyelitis

Answer 10

IV Abx >4 weeks

Curettage of the area if patient is deteriorating

Question 11

What are the complications of osteomyelitis?

Answer 11

Sepsis
Mortality
Growth disturbance in children
Recurrent infection - chronic osteomyelitis