Pre-operative corticosteroid injection within 1 month of total shoulder arthroplasty is associated with increased risk of periprosthetic joint infection

Introduction: Corticosteroid injections (CSI) may increase the risk of peri-prosthetic infections (PJI) following total shoulder arthroplasty (TSA). Our study specifically assessed the risk of PJI in patients who received CSI: (1) less than 4 weeks prior to TSA; (2) 4–8 weeks prior to TSA; and (3) 8–12 weeks prior to TSA. Materials and methods: A national all-payer database was queried to identify patients who underwent TSA with a shoulder osteoarthritis diagnosis from October 1, 2015 to October 31, 2020 (n = 25,422). There were four cohorts: CSI within 4 weeks of TSA (n = 214), CSI 4–8 weeks prior to TSA (n = 473), CSI 8–12 weeks prior to TSA (n = 604), and a control cohort that did not receive CSI (n = 15,486). Bivariate chi-square analyses of outcomes were performed in addition to multivariate regression. Results: A significant increase in PJI risk at 1 year (Odds Ratio [OR] = 2.29, 95% Confidence Interval [CI] = 1.19–3.99, p = 0.007) and 2 years (OR = 2.03, CI = 1.09–3.46, p = 0.016) in patients who received CSI within 1 month of TSA was noted. PJI risk was not significantly increased at any time point for patients who received a CSI greater than 4 weeks prior to TSA (all p ≥ 0.396). Conclusion: PJI risk is increased at both 1 and 2 years post-operatively in patients who received a CSI within 4 weeks of TSA. Therefore, TSA should be deferred at least 4 weeks after a patient receives a CSI to mitigate PJI risk. Level of evidence: Level III.