Patterns and Associated Risk of Perioperative Use of Anti-Tumor Necrosis Factor in Patients with Rheumatoid Arthritis Undergoing Total Knee Replacement

Objective. The patterns and risks of perioperative use of anti-tumor necrosis factor (anti-TNF) medication in patients with rheumatoid arthritis (RA) are not well studied. We examined the patterns of perioperative anti-TNF use and risk of postoperative adverse events (AE) in patients undergoing total knee replacement (TKR). Method. Retrospective cohort study with followup. RA cases within a TKR registry were identified by ICD-9 code (714.0) or self-report. Mailed questionnaires queried anti-TNF use and duration of RA. AE were determined by chart review and patient self-report, and included surgical site infection, pulmonary embolus, deep venous thrombosis, pneumonia, and any infection or re-operation within 6 months. Results. There were 268 TKR cases with RA. The stop time for anti-TNF preoperatively correlated with dosing schedule; restart time was after wound healing. There were 7 surgical site infections (3%), one (0.4%) of which was a deep joint infection in bilateral TKA requiring explant. The anti-TNF group had 126% (3/92) local site infection versus 2.10% (3/143) in the group without anti-TNF and this difference was not statistically significant (Fisher exact test, p = 0.68). The one deep joint infection was in the anti-TNF group. Six-month AE rate was 7.61% in the anti-TNF group versus 6.99% in the group without anti-TNF (Fisher exact test, p = 1.0). Conclusion. There was a low risk of infection and perioperative adverse events in patients with RA receiving anti-TNF therapy who were undergoing TKR. This raises the question whether it is necessary to stop anti-TNF for a long period prior to surgery. Given the possible risks associated with stopping anti-TNF, including worsening of disease, further study is needed to determine optimal perioperative use of anti-TNF among patients with RA undergoing TKR.