Introduction. Treatment of prosthetic joint infection (PJI) following total knee arthroplasty (TKA) may guided by PJI classification, taking into account infection duration and potential for biofilm formation. Debridement, antibiotics and implant retention (DAIR) is recommended for ‘post-operative’ and ‘acute’ haematogenous PJI. However, the time cut-off for ‘post-operative’ PJI varies across classification systems. Furthermore, poor DAIR success rates have been reported in acute haematogenous PJIs. This study aimed to determine the success of DAIR in a large cohort of PJIs, and assess the utility of current classification systems for predicting DAIR outcomes. Method. In this multicentre retrospective, cohort study, we identified 230 patients undergoing DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors were identified, and PJI subtype, post-operative antibiotic regime and treatment outcomes were recorded. Statistical analysis was performed to identify factors associated with failed DAIR, and success rates were analysed by multiple classification systems using receiver operating characteristic (ROC) curves. Results. At average follow-up of 6.9 years, DAIR failed in 46% of cases. ROC analysis found 3 month and 1 year cut-offs for ‘post-operative’ PJIs were equally predictive of outcomes (AUC=0.63). On multivariate survival analysis, DAIR failed in 63% of late haematogenous PJIs (implant age>1 year) compared to 36% of early (<1year) PJIs (OR=1.78, p=0.01). Staphylococcus aureus (OR=4.70, p<0.001) and gram negative infections (OR=2.56, p=0.031) were risk factors for DAIR failure in late PJIs. Conclusions. We found a high failure rate in late infections following TKA, irrespective of their classification as ‘acute haematogenous’ or ‘chronic’. Higher DAIR success rates were seen with implant age <1year. These findings call into question the utility of current classification systems based on duration of bacterial presence. For late infections (>1year), PJI caused by S. aureus or gram negative bacteria have a higher failure rate when treated with DAIR

Aims

The aims of this study were to compare the mean duration of antibiotic release and the mean zone of inhibition between vancomycin-loaded porous tantalum cylinders and antibiotic-loaded bone cement at intervals, and to evaluate potential intrinsic antimicrobial properties of tantalum in an in vitro medium environment against methicillin-sensitive Staphylococcus aureus (MSSA).

Aims

We propose a state-of-the-art temporary spacer, consisting of a cobalt-chrome (CoCr) femoral component and a gentamicin-eluting ultra-high molecular weight polyethylene (UHMWPE) tibial insert, which can provide therapeutic delivery of gentamicin, while retaining excellent mechanical properties. The proposed implant is designed to replace conventional spacers made from bone cement.

Aims

Knee joint distraction (KJD) is a relatively new, knee-joint preserving procedure with the goal of delaying total knee arthroplasty (TKA) in young and middle-aged patients. We present a randomised controlled trial comparing the two.