significance of perioperative tests to diagnose the infection in revision total shoulder arthroplasty

Background: the purpose of this study was to evaluate the value of perioperative tests for the diagnosis of infectionin revision shoulder arthroplasty.methods: a retrospective analysis was performed on 537 shoulder arthroplasties (429 patients) that underwent revisionshoulder arthroplasty at our institution. periprosthetic tissue cultures were positive in 169/537 surgeries.results: white-blood cell count (wbc) was elevated in 3.8% revision arthroplasties. erythrocyte sedimentation rate (esr)was elevated in 23.1% revision arthroplasties. the c-reactive protein (crp) was elevated in 20.8% revision arthroplasties.bone scans (technetium, indium) were performed on 9.9% patients and it was positive for osteomyelitis in just one revisionarthroplasty. intra-operative pathology was read as consistent with acute inflammation in 11.9% revision arthroplasties.the positive and negative predictive values for intra-operative pathology were 56.7% and 71.6% respectively.conclusion: all of the perioperative tests had a high specificity and negative predictive value, but low sensitivity andpositive predictive value.