Significance of Perioperative Tests to Diagnose the Infection in Revision Total Shoulder Arthroplasty

The purpose of this study was to evaluate the value of perioperative tests for the diagnosis of infection
in revision shoulder arthroplasty. A retrospective analysis was performed on 537 shoulder arthroplasties (429 patients) that underwent revision
shoulder arthroplasty at our institution. Periprosthetic tissue cultures were positive in 169/537 surgeries. 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 revision
arthroplasty. 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. All of the perioperative tests had a high specificity and negative predictive value, but low sensitivity and
positive predictive value.