- 3 of 5 criteria: (i) Elevated erythrocyte sedimentation rate (ESR) (>30mm/jr) and c-reactive protein (CRP) (>10mg/L) (ii) Elevated synovial leukocyte count (>3000 cells/µL) or change of ++ on leukocyte esterase strip (iii) Elevated synovial neutrophil percentage (>80%) (iv) One positive culture (v) Positive histological analysis of periprosthetic tissue (>5 neutrophils per high power field in 5 high power fields x400)