We sought to determine if reoperation-free survival following irrigation and debridement with polyethylene liner exchange of acutely infected primary TKA is affected by: 1) postoperative antibiotic duration; 2) patient characteristics or surgical factors; 3) infecting organism; or 4) whether infection was acute postoperative versus hematogenous.
Of revision TKAs from 2004 to 2012 (n = 1735), 76 underwent irrigation and debridement (I&D) with liner exchange after primary TKA with mean 3.5-year follow-up. We analyzed those requiring reoperation for infection (n = 21) versus those who did not (n = 55).
Increased duration of postoperative antibiotic therapy (p = 0.0163) decreased reoperation for infection. Atrial fibrillation (p = 0.0053), chronic obstructive pulmonary disease (COPD) (p = 0.0122), more than 15 cells per high powered field (HPF) (p = 0.0124), or higher preoperative C-reactive protein (p = 0.0025) increased reoperation for infection. Incidence of infection recurrence was highest with Methicillin resistant S. aureus (MRSA) and lowest with Gram negative organisms. There was no difference in reoperation-free survival between acute postoperative and hematogenous infections.
Reoperation-free survival following I&D with polyethylene liner exchange of acutely infected primary TKA: 1) improves with increased postoperative antibiotic therapy duration so chronic antibiotic suppression should be considered following TKA I&D with liner exchange; 2) is worse with atrial fibrillation, COPD, >15 cells/HPF, preoperative C-reactive protein >500 mg/L, or MRSA so two-stage revision may be favored in these patients; and 3) is equivalent in acute postoperative and hematogenous infections.