Major criteria | |
 1. Two positive periprosthetic cultures with phenotypically identical organisms | |
 2. A sinus tract communicating with the joint | |
Minor Criteria | |
 1. Elevated serum C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) | |
 2. A single positive culture | |
 3. Elevated synovial fluid white blood cell (WBC) count or ++ change on leukocyte esterase test strip | |
 4. Elevated synovial fluid polymorphonuclear neutrophil percentage (PMN%) | |
 5. Positive histological analysis of periprosthetic tissue |