Success of Debridement and Implant Retention for Periprosthetic Joint Infection in TKA – Does The Surgeon Matter?

INTRODUCTION: Prosthetic joint infection (PJI) is a devastating complication following total knee arthroplasty (TKA). In acute haematogenous and early post-operative PJI, debridement and implant retention (DAIR) is often the initial treatment and reported success rates vary. The aim of this study was to identify factors affecting the success of DAIR and in particular whether involvement of a lower limb arthroplasty surgeon (LLA) can affect outcome. METHOD: In a multicentre review over a 15 year period we identified 137 patients undergoing DAIR for first episode PJI following primary TKA at one of three tertiary hospitals. Patients receiving arthroscopic washouts, culture negative PJI, and previous PJIs were excluded. Data on patient, hospital, and surgical factors were identified including age of implant, time to theatre, presence of gross purulence, bacterial subtype, inflammatory markers, relevant comorbidities, whether modular component exchange was performed, and whether a lower limb arthroplasty surgeon performed the procedure. Treatment success was defined as infection eradication characterized by no clinical failure (healed wound and painless joint) or infection recurrence, and no mortality or further surgery due to PJI within minimum two-year follow up post DAIR. Multivariate analysis was performed using a logistic regression model to identify factors associated with successful DAIR. RESULTS: Overall failure rate of DAIR in TKA was 42%. A specialist arthroplasty surgeon was present in 49% of cases. Arthroplasty surgeons performed modular exchange in 92% of cases compared to 57% for other surgeons (RR1.6, P <0.01). On multivariate analysis, involvement of a specialist arthroplasty surgeon was the only factor associated with a significant increase in success of DAIR (OR 2.94, P=0.01). Age of prosthesis less than 90 days and the lack of macroscopic purulence (OR 2.44, p=0.04) increased DAIR success on univariate analysis only. CONCLUSIONS: Involvement of a specialist arthroplasty surgeon was associated with a 2.9 times higher success rate for DAIR in TKA. Specialist arthroplasty surgeons were more likely to perform modular exchange. This study suggests surgical technique and thorough debridement is likely to be important to the success of DAIR in TKA.