Repeat two-stage revision for knee prosthetic joint infection results in very high failure rates

Introduction Two stage revision total knee arthroplasty (TKA) is the gold standard for treatment and eradication of knee prosthetic joint infections (PJI), but the literature is limited on the outcomes of repeat two-stage TKA after PJI recurrence. This study presents the outcomes of repeat two-stage revision TKA and investigates potential factors contributing to success or failure, aiming to assist counselling and decision-making. Methods A retrospective study was undertaken investigating all two-stage revision TKA performed at one institution between 2005 and 2020. Twenty cases underwent repeat two-stage revision TKA. Patient outcomes and factors contributing to treatment success or failure were investigated. PJI was diagnosed according to MSIS criteria. Results Of the 20 cases, 14 were classified as failed treatment (70%) due to a failure to eradicate infection, further surgical intervention or death. In this cohort, there were no statistically significant differences between the groups regarding factors contributing to treatment success or failure. In the success group, patient reported functional outcomes were variable. Conclusion This study demonstrates that patients undergoing a repeat two-stage TKA have very poor outcomes. This study did not identify any factors that predicted failure. Patients need to be counselled regarding poor outcomes with repeat two-stage TKA, and other treatment options such as early amputation or lifelong suppression should be considered.