Do We Need to Wait 3 Months After Corticosteroid Injections to Reduce the Risk of Infection After Total Knee Arthroplasty?

Sarah Bhattacharjee, BS; Sara Wallace, MD; Hue H. Luu, MD; Lewis L. Shi, MD; Michael J. Lee, MD; Antonia F. Chen, MD, MBA


J Am Acad Orthop Surg. 2021;29(14):e714-e721. 

In This Article

Abstract and Introduction


Background: Corticosteroid injections administered within 3 months before total knee arthroplasty (TKA) have been linked to increased risk of postoperative infection. However, it would be beneficial to further delineate the timing of injections to determine whether a narrower window exists for safe administration of corticosteroid injections. The purposes of our study were to (1) determine whether there were a different time frame between corticosteroid injection and primary TKA that increased infection risk and (2) determine risk factors associated with infection after TKA.

Methods: TKA patients were identified from a national database from 2007 to 2017 and stratified based on their history of corticosteroid injections within the 6-month preoperative period. Patients who received injections were stratified into biweekly cohorts by the timing of their most recent injection. The 1-year rate of postoperative infection treated by surgical débridement was compared between injection and noninjection cohorts. Univariate logistic regressions of risk factors and a multivariate analysis for patient comorbidities and injection cohorts associated with increased infection risk were conducted.

Results: In the 76,090 TKA patients identified, corticosteroid injection within 2 weeks before TKA increased the risk of postoperative infection (P = 0.02) and injections within 2 to 4 weeks trended toward increased infection in univariate regression. No significant differences were observed in any other injection time frames. In the multivariate analysis, injections within 2 weeks before TKA were identified as an independent risk factor (odds ratio: 2.89; P = 0.04) for postoperative infection. Additional risk factors included chronic obstructive pulmonary disease, coronary artery disease, diabetes, ischemic heart disease, obesity, rheumatoid arthritis, and tobacco, whereas female sex and patient aged older than 65 were protective.

Discussion: Our results suggest that TKA performed within four weeks of a corticosteroid injection may be associated with a higher risk of postoperative infection; however, delaying surgery more than four weeks may not provide additional infection risk reduction. Further prospective randomized studies are needed to determine the optimal timing of TKA after corticosteroid injections.

Level of Evidence: Level III


Intra-articular corticosteroid injections are well known for decreasing pain associated with knee osteoarthritis.[1,2] Because corticosteroid injections are easily administered and have been shown to reduce inflammation, they are most commonly performed before total knee arthroplasty (TKA) to provide nonsurgical pain relief.[3–5] However, because immunocompromise and predisposition for infection after surgery are well-documented adverse effects of corticosteroid administration, the optimal timing of intra-articular corticosteroid injections to reduce these potential adverse effects after surgery has been the subject of much discussion in the literature.[1,3,6–8] Studies assessing the effects of preoperative corticosteroid injections in total hip arthroplasty, shoulder arthroscopy, and single-level lumbar fusion populations have substantiated the claim that the timing of injection before surgery may influence postoperative infection outcomes.[9–12]

Although there have been reports suggesting no such association between presurgical intra-articular corticosteroid injections and postoperative TKA surgical site infection,[13,14] a 2015 study by Cancienne et al.[15] using a Medicare database observed that intra-articular corticosteroid injections received within 3 months before TKA were markedly associated with a higher rate of postoperative infection, whereas in 2016, Bedard et al[16] reported that in a private insurance database analysis, injections received within 6 months before TKA were markedly associated with a higher rate of postoperative infection. Many surgeons, therefore, refrain from administering intra-articular steroid injections for at least 3 months or up to 6 months before TKA out of concern for elevating the risk for postsurgical infection. Although the practice is well intended, it does deprive patients of an option for pain relief in the interim period before surgery.

Although contemporary literature has formed the basis of the current standard of care, these studies are limited because of the wide breadth of timing intervals examined, such as injections received within 0 to 3 months and 3 to 6 months as in the study by Cancienne et al,[15] or the broad definition used for injection, such as the Current Procedural Terminology (CPT)-20610 billing code that is also used for hip and shoulder injections as in the analysis by Bedard et al.[16] Moreover, both of these studies did not control for the type of injection administered and thus cannot accurately comment on the effects of corticosteroid injections specifically. A more granular study assessing corticosteroid knee injections could expose a narrower period associated with increased risk for postoperative infection, for example, within 1 month of TKA rather than 3 months. Thus, the purposes of this study were to (1) determine whether there was a different time frame between corticosteroid injection and primary TKA that increased the risk of infection and (2) determine risk factors associated with infection after TKA.