Osteomyelitis Flashcards
What is osteomyelitis?
Inflammation in the bone and bone marrow
What is the common source of infection?
Haematogenous osteomyelitis- carried through the blood
What is the most common causative organism?
Staph. aureus
What are the risk factors for developing osteomyelitis?
Open fractures
Orthopaedic operations
Diabetes
Peripheral arterial disease
IV drug use
Immunosuppression
What is the pathology of osteomyelitis?
- Starts at metaphysis
- Vascular stasis
- Acute inflammation → increased pressure
- Suppuration
- Release of pressure- ruptures
- Necrosis of bone (sequestrum)
- New bone formation (involucrum)
- Resolution or chronic osteomyelitis
What is a sequestrum?
A piece of dead bone that has become separated during the process of necrosis from normal or sound bone
What is an involucrum?
A thick sheath of periosteal new bone surrounding a sequestrum
What are the clinical features of osteomyelitis?
Non specific symptoms
Fever
Pain and tenderness
Erythema
Swelling
What investigations are done for osteomyelitis?
MRI
WCC, CRP, ESR
Blood cultures
Bone cultures
X ray
What are the signs on x ray?
Periosteal change
Osteopenia (bone thinning)
Late osteonecrosis- sequestrum
Late periosteal new bone- involucrum
What are the differentials for ostemyelitis?
Septic arthritis
Trauma
Transient synovitis
Soft tissue infections
What is the management of osteomyelitis?
Supportive treatment
Surgical debridement
Antibiotic therapy
Rest and splinatge
What antibiotic therapy is used?
Acute- 6 weeks of flucloxacillin
Chronic- 3 months of flucloxacillin
What are complications of osteomyelitis?
Metastatic infection
Pathological fracture
Septic arthritis
Septicaemia
Squamous cell carcinoma
