What is septic arthritis?
Infection inside a joint
Emergency - infection can quickly begin to destroy the joint and cause systemic illness
What age is most commonly affected in septic arthritis?
Occurs at any age but most common in children <4 years
What is the mortality in septic arthritis?
10% mortality
What is septic arthritis a common complication of?
Joint replacement
Occurs in 1% of straight forward hip and knee replacements (higher in revision surgery)
How does septic arthritis present?
- usually single joint affected (often hip or knee)
- hot, red, swollen, painful joint
- refusal to weight bear
- stiffness, reduced ROM
- systemic symptoms (fever, sepsis, lethargy)
Can be SUBTLE in children
What is the most common causative organism in septic arthritis?
- S. Aureus
What other causative organisms are there for septic arthritis?
- Neisseria gonorrhoea (sexually active teenagers)
- Group A streptococcus (S. pyogenes)
- H. influenza
- E.coli
What are differential diagnoses for septic arthritis?
- transient synovitis
- Perthes disease
- SUFE (slipped upper femoral epiphysis)
- juvenile idiopathic arthritis
What is the management for septic arthritis?
- admit to hospital
- involve orthopaedic team
- joint aspiration (gram staining, crystal microscopy, culture, antibiotic sensitivities)
- empirical IV antibiotics (until microbial sensitivities known)
- continue abx for 3-6 weeks
What management may be required in severe cases of septic arthritis?
Surgical drainage and washout of the joint to clear infection
