Early aseptic reoperation after shoulder arthroplasty increases risk of subsequent prosthetic joint infection

BACKGROUND: Despite the success of anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA), the clinical course of some patients necessitates operative intervention in the acute postoperative period. In this study, we evaluate the risk of subsequent prosthetic joint infection (PJI) in patients who undergo an aseptic reoperation within 90 days of primary shoulder arthroplasty. METHOD: A retrospective review of patients with primary TSA and RSA was performed using a commercially available national database (PearlDiver Inc., Fort Wayne, IN, USA). Queries were performed with use of International Classification of Diseases, Ninth Revision and Tenth Revision and Current Procedural Technology codes. Patients were divided into cohorts based on undergoing aseptic reoperation, reoperation for PJI, or no reoperations within 90 days of index procedure. Primary outcome was subsequent PJI within 1 year of index procedure. Observed PJI rates were compared using chi-square analysis. Risk factors for PJI were compared using logistic regression. RESULTS: From 2010 to 2018, a total of 96,648 patients underwent primary shoulder arthroplasty: 46,810 underwent TSA and 49,838 underwent RSA. The rate of aseptic reoperation within 90 days was 0.72% and 1.5% in the TSA and RSA cohorts, respectively. At 1 year postoperatively, patients who underwent an aseptic reoperation within 90 days had an elevated risk of subsequent PJI compared with the overall rate of PJI in the TSA (3.54% vs. 0.75%; P < .001) and RSA (3.08% vs. 0.73%; P < .001) cohorts. On multivariate logistic regression analysis, aseptic reoperation within 90 days was identified as a significant risk factor for subsequent PJI in the TSA cohort (odds ratio, 14.19; P < .001) and RSA cohort (odds ratio, 8.38; P < .001). The most common indication for aseptic reoperation was postoperative prosthetic joint instability in both the TSA (31%) and RSA (49%) cohorts. CONCLUSION: Aseptic reoperation within 90 days of primary TSA or primary RSA was associated with a notably increased risk of subsequent PJI.