F2 and infection: At present, a plain radiographic examination and laboratory assessments, such as ESR, CRP, prothrombin consumption time, white blood cell count of synovial fluid, percentage of polymorphonuclear cells, blood and tissue cultures, are the diagnostic methods for recognizing an infection after hip replacement.[10] The combined application of these methods is the basic technique for confirming/excluding the diagnosis of a periprosthetic joint infection (PJI) after THA.[11,12] When these indicators are negative, however, the diagnostic information provided is of relatively limited use.