Septic arthritis

Question 1

What is septic arthritis?

Answer 1

An infection inside a joint

Question 2

What is the presentation of septic arthritis?

Answer 2

Single joint affected
Hot, red, swollen, painful joint
Refusing to weight bear
Stiffness and reduced range of motion
Fever

Question 3

What is the most common causative organism of septic arthritis?

Answer 3

Staphylococcus aureus

Question 4

What other bacteria can cause septic arthritis?

Answer 4

Neisseria gonorrhoea
Group A strep
Haemophilus influenzae
E. coli

Question 5

What are the differentials of septic arthritis?

Answer 5

Transient synovitis
Perthes disease
Slipped upper femoral epiphysis
JIA

Question 6

What are the risk factors for septic arthritis?

Answer 6

Extremes of age
Diabetes
Malnutrition
Peripheral vascular disease
Malignancy

Question 7

What is the definitive investigation for septic arthritis?

Answer 7

Joint aspiration culture, microscopy and sensitivity

Question 8

What other investigations may be performed in suspected septic arthritis?

Answer 8

Inflammatory markers
Blood culture
Imaging - X-ray, CT, MRI
Cultures of expressed pus

Question 9

What is the first line management of septic arthritis?

Answer 9

IV antibiotics for 3-6 weeks
- Empirical and then specific once sensitivies are known

Question 10

What is the managment of a child under 3 with a limp?

Answer 10

Refer urgently to paediatrics to assess for septic arthritis