This retrospective study aims to improve the diagnosis of PJI as well as to identify microorganisms causing periprosthetic joint infection (PJI) and the drug-resistant spectrum

160 patients who underwent revision or re-revision total hip or knee arthroplasty for different reasons in our institution were recruited from August 2013 to August 2016. 80 patients meet the criteria of PJI from the muscle and skeletal muscle Association (MSIS) are divided to the infection group, another 80 patients are divided into the non-infection group.

Medical and demographic data were recorded. Collected lab examinations included blood routine test, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), synovial leukocyte counts, Receiver Operating Characteristic Curve-Area Under Curve (ROC-AUC) analysis will be used to evaluate the specific and sensitivity of diagnosis index. Moreover,microorganisms isolated from periprosthetic tissues and articular fluid. Postoperatively, the prosthesis was sent for ultrasound sonication. The sonicate extraction, implant surrounding tissue and synovium were sent for microbiologic culture, and the implant-surrounding-tissue were also sent for pathological examination. The isolated strains and drug-resistance rate for each bacterium for different antibiotics were presented.

Inclusion Criteria:

• patient who underwent revision or re-revision total hip or knee arthroplasty for different reasons in our institution

Exclusion Criteria:

1. Patients who refused to join the trial group;
2. Revision total hip/knee replacement for periprosthetic fracture;
3. patients who missed some of important examination;
4. Revision total hip/knee replacement for metal sensitivity;
5. Revision total hip/knee replacement for the last period of second-stage revision;
6. Patient who underwent revision with RA or other inflammatory disease.

Patient who underwent revision or re-revision total hip or knee arthroplasty for different reasons in our institution