Septic Arthritis

Question 1

What are the risk factors for septic arthritis? (6 things)

Answer 1

1. Age (80+ yrs)
2. Pre-existing joint disease (RA)
3. DM / Immunosuppression
4. Chronic renal failure
5. Hip / knee joint prosthesis
6. IV drug use

Question 2

What are the clinical features for septic arthritis? (4 things)

Answer 2

1. Single hot + swollen joint
2. Joint tenderness
3. Reduced ROM / X weight bear
4. Pyrexia (60%)
   (symptoms more subtle in prosthetic joint)

Question 3

What are some differentials for septic arthritis? (4 things)

Answer 3

1. Infection
2. Inflammatory arthropathy (gout or pseudo gout in adults / reactive arthritis in kids)
3. Post traumatic swelling / bleeding in joint
4. Flare up of OA

Question 4

What investigations should be done for septic arthritis? (4 things)

Answer 4

1. Bloods
2. Joint aspiration
3. Blood cultures
4. MRI

Question 5

What bloods should be done for sus septic arthritis? (5 things)

Answer 5

1. FBC
2. CRP
3. ESR
4. Urate levels
5. Blood cultures

Question 6

What is the gold standard imaging technique for septic arthritis?

Answer 6

MRI

Question 7

Why should you aspirate a joint before starting abx?

Answer 7

Cah you need to have a good sample, if you start abx and then aspirate and culture etc you will find nothing

Question 8

What should a joint aspirate be sent for? (4 things)

Answer 8

1. Gram stain
2. Leucocyte count
3. Culture
4. Polarizing microscopy

Question 9

What should be the initial management for septic arthritis?

Answer 9

Abx ASAP (make sure after aspiration / culture)

Question 10

What is the management option for a Native joint with septic arthritis? (2 things)

Answer 10

1. Surgical irrigation

2. Debridement

Question 11

What is the management option for a Prosthetic joint with septic arthritis? (2 things)

Answer 11

1. Surgical irrigation + debridement

2. Revision surgery

Question 12

What are the complications of Septic arthritis? (2 things)

Answer 12

1. OA

2. Osteomyeltis