• BACKGROUND
    • Recent literature has advocated for the effectiveness of postoperative steroid injections following total knee arthroplasty (TKA) for improving pain and range of motion when other correctible causes of these symptoms have been eliminated. The safety of such injections has not been thoroughly evaluated. The aim of this study was to determine the risk of acute infection following intra-articular corticosteroid injection into a preexisting TKA.
  • METHODS
    • The Humana dataset was used to identify patients who underwent TKA from 2007 to 2017. Patients with ipsilateral knee corticosteroid injections in the postoperative period were then identified and compared to a 2:1 matched control cohort. A diagnosis of infection within 6 months and 1 year following the injection and an ipsilateral procedure for infection at any time postoperatively were then assessed and compared to controls using a multivariate binomial logistic regression analysis.
  • RESULTS
    • Of the 166,946 TKA performed during the study period, 5628 patients had a postoperative corticosteroid injection (3.4%). Patients with injections had a significantly higher rate of periprosthetic infection compared to noninjection matched controls at all studied time points.
  • CONCLUSION
    • In a large national database, about 3% of patients who undergo TKA have a postoperative steroid injection into their postoperative knee. While there is some existing literature demonstrating improvement in pain and stiffness symptoms after TKA with postoperative injections, the present study demonstrates a significant correlation between postoperative intra-articular corticosteroid injections in patients with preexisting TKA and periprosthetic joint infection compared to matched controls who did not receive an injection.