Bone Infections

Question 1

What pathogens are the most commonn pathogens to cause surgical site infection?

Answer 1

1. Staph.aureus
2. E.coli (gram-nevative therefore more common in abdominal infection)
3. Pseudomonas aeroginosum

Question 2

What are the three levels of SSI (surgical site infection)

Answer 2

1. Superficial incisinal
2. Deep insicional
3. Organ/tissue specific

Question 3

What is the ASA score?
What is the connection to risk for Surgical site infection?

Answer 3

Score to asess patients overall health (1-5)
ASA score of 3 or more at increased risk for surgical site infections

Question 4

What is the recommended soloution for sterilisation of surgical sites?

Answer 4

Chlorhexidine 70% in Alcohol

Question 5

What are the most common bacteria to cause septic arthritis?

Answer 5

1. Staph Aureus (46%)
2. Streptococci (22%)
3. Gram -ve : less common

Question 6

What is the synovial WCC cut off-for septic arthritis?

Answer 6

> 500.000 cells/ml

Question 7

What is the abx of choice + regimen for Septic arthritis?

Answer 7

IV Cephalosporin or Flucloxaclllin (+/- vancomycin if high risk for MRS)
2 Weeks IV + 4 weeks oral (or 6 Weeks IV if slow response)

Question 8

What are the most common organisims for vertebral osteomyelitis?

Answer 8

1. Stap Aureus
2. Streptococci

Question 9

What is a Brodies abscess?

Answer 9

Intra-ossear abscess

Question 10

What is sinus tract?

Answer 10

Seen in chronic osteomyelitis and also Prosthetic joint infnectionn

Question 11

What are the most common organisims causing prosthetic joint infecitons?

Answer 11

1. Coagulase -ve Staph aureus
2. Streptococci

Question 12

What is DAIR?

Answer 12

Method for treating prostthetic joind infection:

debridement, antibiotics and implant retention

Question 13

What methods are available for management of Prosthetic Joint infections?

Answer 13

1. Single stage revision (old out and new in in one step)
2. Two stage revision (old out, 6 weeks waiting, new in)
3. DAIR

Question 14

What is the management plan for chronic osteomyeliits?

Answer 14

Masquet technique

• Radical sequestrectomy
• Removal of foreign bodies; filling the defect with antibiotic loaded cement spacer and external fixation
• In 6-8 weeks , remove the cement spacer, and fill the defect with autologous bone graft

Question 15

How is joint aspirate sampling done for the diagnosis of prosthetic joint infections?

Answer 15

1. Cells from 5 sites around implant
2. if 3 or more yield same infection: likely pji

Question 16

How is surgical site infection diagnoised?

Answer 16

Clinical + wound swaps

Question 17

How is Osteomyelitis diagnoises?

Answer 17

MRI (Bone marrow oedema + fluid,
Blood culture
Bone biopsy for culture / histology

Question 18

What is the choice of antibiotics in treatment of Surgival site infection?

Answer 18

Flucloxacillin for staph