STAGE 1 REVISION , DAIR

1. Infected TKA
1. DAIR
2. Stage 1 revision
Dr Aditya Apte
Sunshine hospitals

2. • Foreign object
• Inefficient phagocytic response ,Neutrophil degranulation
• Frustrated phagocytosis
• Minimum infective conc. Of bacteria decreases by 10(5)

3. • INCIDENCE – (2016)
• Primary tka- 0.8 – 1.5 %
• Primary tha – 1 – 2.7 %

4. MSIS 2011 :
1. There is a sinus tract communicating with the prosthesis; or
2. A pathogen is isolated by culture from at least two separate tissue or
fluid samples obtained from the affected prosthetic joint; or
3. 4/6 of following :
a. Esr >30mm/hr , crp >10mg/l
b.Synovial wbc > 20,000
c. Synovial PMN % > 89 %
d. Presence of purulence in the affected joint
e. Isolation of microorganism in one culture
f. > 5 neutrophils / hpf in 5 hpf ( 400x magnification )

6. • 1. antibiotics
• 2. DAIR
• 3. two stage revision
• 4. single stage revision
• 5. arthrodesis , amputation
• Success rate –
• Time interval
• Immune status / comorbidity
• Virulence

7. I-Acute postoperative- < 4 weeks
II-Late chronic - > 4 weeks
III-Acute hematogenous
IV-Positive intra op culture – two or more positive intra op cultures
I,III- DAIR
II- Staged revision
IV- antibiotics

8. Mcpherson 1999
eg. II, B , 1

9. Mary charlson,1986 , New York

10. Success rate
• Coagulase neg staph
• Staph aureus
• Streptococci
• MRSA

11. DAIR
112 cases , success rate 78% at 3 years

12. • Excision of wound margins
• Debridement of necrotic soft tissues and debris
• Collection of pus samples from multiple sites
• Assess prosthesis integrity
• Exchange modular component
• Pulse lavage( HV + LP , 6-9L) + 0.05 % aqueous chlorhexidine solution
• Primary closure + drain

13. *Preoperative antibiotic omission – no longer recommended
• Empirical antibiotic therapy – best avoided
• inj vancomycin 1g bd + inj meropenem 500mg tds
• Reports- modified accordingly
• 6 weeks iv + upto 12 months oral
• No role of extended iv antibiotics

14. Contraindications for DAIR
• 1. Loose prosthesis
• 2. sinus tract
• 3. inability to close the wound
• 4. mrsa / polymicrobial

15. Ideal DAIR -
• 1. within 4 to 6 weeks
• 2. low virulence
• 3. non immunocompromised host
• 4. THOROUGH DEBRIDEMENT + poly exchange
• 5. 6-8 weeks of iv antibiotics

16. Worse prognosis :
1.SCORE > 3
2. S. aureus

17. 1. intraarticular antibiotics ? X
2.Antibiotic impreg. Pellets ? X
3. NO ROLE OF MULTIPLE DAIRS

18. Role of rifampicin ? 2x450mg x 6weeks

19. 1. Not time dependent…

20. Delphi criteria :
1. no infection recurrence caused by same strain
2. no subsequent surgical intervention
3. no infection related mortality
follow up- short – 2y
medium- 5y
long - > 10y

21. Stage 1 revision :
• Insall 1983- first two stage revision
• Booth – 74 %

22. Exposure
• Prior incision is used
• Multiple – lateral most
• Sinuses- incorporated and excised
• Avoid subcutaneous dissection
• Incision depth – upto deep fascia

24. “ most important step in revision is
DEBRIDEMENT.. If that is compromised all
subsequent surgeries will surely fail “ – J. Parvizi
• Preferably without tourniquet
• Better demarcation
• Excise all dead , necrotic tissue

25. Implant removal
• Poly – femur – tibia
• Specialised extractor sets
• Longitudnal force
• Implant –cement interface

28. • Antibiotic properties –
• Heat stable
• Broad spectrum
• Low risk of allergy
• Powder form ( homogenous distribution )
• Avoid vacuum mixing
• < 4g/40gm pmma
• vancomycin (2g), tobramycin( 2.4g), cefuroxime (1.5g) / 80 gm
• High initial release.. Constant elution over next few days

29. • Passive oppurtunism –
• Better elution properties on addition of a second antibiotic
• Addition of tobramycin in 40g pmma , improves the elution of
vancomycin

30. • Static spacer –
• Joint distraction
• Stability
• Articulating spacer –
• Reduced bone loss
• Allows partial wt bearing
• Better ROM

32. Articulating spacers
• 1.Cement on cement –
• Stainless steel mold for femur
• Stemmed all cement tibial tray
• Prevent interdigitation – tourniquet released

33. • 2.Cement on polyethylene –
• All cement femoral component + antibiotic cement coated thin tibia
poly
• Highest rates of reinfection

34. • 3. Metal on polyethelene –
• Reimplant femoral component + thin tibial poly

37. • Jamsen et al-
• All cement vs Hoffmann technique
• Better outcome -decreased blood loss
• Better post op KSS

40. 1.Better than prostalac
2.no metal/poly surface
3.better antibiotic elution

41. Foil technique 2007 , IJO

43. 1. Similar reinfection rates
2. Better rom ( 107 vs 84)

45. 1. Small molecules- d aminoacids , n acetyl cysteine
2. Matrix targeting enzymes – dispersin B

46. • Thank you.