Most patients suffering from arthritis receive multiple steroid or hyaluronic acid injections before electing TJA. In theory, injections pose the risk of introducing bacteria into the joint. The risk of septic arthritis secondary to steroid injection is low, and the bacterial load at inoculation is unknown. What is the risk that bacteria persists within a joint and leads to PJI after TJA> Charalambous et al. looked at antiseptic techniques used in the offices of general practitioners, rheumatologists and orthopedic surgeons within the UK when administering steroid injections. [1]. Less than 50% of doctors used betadine or chlorhexadine to preop the injection site, less than 1/3 routinely used sterile gloves, yet only 10% reported seeing septic arthritis secondary to injection. These findings certainly suggest that many offices perform injections under substandard protocols that probably increase the risk for bacterial infection, but it does not answer whether this risk is clinically relevant.
Other studies have looked specific at rates of PJI and the timing of steroid injection. Papavasiliou et al. looked at 144 TKA and found a higher rate of deep infection in those receiving steroid injection within the last year [2]. Cancienne et al. looked at timing of steroid injection within 3 months or within 6 months of TKA, and found a significant increase in PJI if steroids were giving within 3 months of surgery but not within 6 months [3]. Yet Charalambous et al. found no correlation with deep or superficial infection in their meta-analysis of reported PJI after TKA and its association with steroid injection [1]. However, the meta-analysis is likely unable to distinguish between critical time periods for exposure, and thus many surgeons believe injections should be held within 3 months of surgery.
Injections are less commonly performed in patients with hip arthritis because the technique is more challenging and fewer physicians are comfortable performing an in-offices injection. However, steroid injections are still performed in the hip and studies have similarly examined the risk of PJI when this injection preceeds THA. Kaspar et al found increased PJI in hips that were previously injected, although timing of the injections were not discussed [4]. Meermans examined 175 patients that received steroid injections under sterile conditions within 1 year of THA and found no added risk of PJI [5]. McIntosh et al. similarly didn’t find increased risk of PJI in patients injected within 1 year of THA, however, the average time to injection for the 3 out 217 patients that developed PJI was only 40 days, which was not statistically significant but does highlight a concern about injecting steroids soon before surgery.
REFERENCE
1. Charalambous, C.P., et al., Septic arthritis following intra-articular steroid injection of the knee--a survey of current practice regarding antiseptic technique used during intra-articular steroid injection of the knee. Clin Rheumatol, 2003. 22(6): p. 386-90.
2. Papavasiliou, A.V., et al., Infection in knee replacements after previous injection of intra-articular steroid. J Bone Joint Surg Br, 2006. 88(3): p. 321-3.
3. Cancienne, J.M., et al., Does Timing of Previous Intra-Articular Steroid Injection Affect the Post-Operative Rate of Infection in Total Knee Arthroplasty? J Arthroplasty, 2015. 30(11): p. 1879-82.
4. Kaspar, S. and V.d.B.J. de, Infection in hip arthroplasty after previous injection of steroid. J Bone Joint Surg Br, 2005. 87(4): p. 454-7.
5. Meermans, G., K. Corten, and J.P. Simon, Is the infection rate in primary THA increased after steroid injection? Clin Orthop Relat Res, 2012. 470(11): p. 3213-9.