Septic Arthritis

Question 1

What is the epidemiology of septic arthritis?

Answer 1

Children
Young adults
Elderly
LEDs
Less common than osteomyelitis

Question 2

What is the pathology of septic arthritis?

Answer 2

Infection via bloodstream - spreads from metaphysis or penetrating trauma
Bacteria settle in synovium
Proliferation causes inflammatory response
Leukocytes migrate to joint
Enzymes and products of breakdown damage cartilage

Question 3

What bacteria cause septic arthritis?

Answer 3

Staphylococcus aureus
Neisseria gonorrhoea
Haemolytic streptococcus

Question 4

What are the symptoms of septic arthritis?

Answer 4

Hot, swollen joints
Fever
Tachycardia
History of systemic infection
Unbearable pain on movement
Cannot weight bear

Question 5

What investigation would you do for septic arthritis? And would the positive results be?

Answer 5

raised WCC
raised CRP
raised ESR
normal X-rays
Ultrasound - joint effusion of hip
Fluid aspiration

Question 6

What would you see in a fluid aspiration of septic arthritis?

Answer 6

Opaque
Yellow
WBC > 80,000
bacteria in culture

Question 7

What is the management of septic arthritis?

Answer 7

Analgesia
Limb splint
Aspiration
Antibiotics
Serial aspiration
Arthroscopy/arthotomy

Question 8

What are the complications of septic arthritis?

Answer 8

Spinal infection
Recurrence of infection
Joint destruction
Avascular necrosis