Abstract
Introduction
In rheumatoid (RA) patients undergoing total joint arthroplasty, evidence suggests methotrexate should be continued without increase in post-operative infection. Prednisolone increases post-operative infection risk, but cannot be stopped without risk of Addisonian events. Insufficient evidence exists to clarify perioperative biologic agent management. We currently stop biologics 2 weeks prior to operation and reintroduced following wound healing.
Patients/Materials & Methods
This service evaluation reviewed infection rates and length of stay in RA patients following lower-limb arthroplasty, on various anti-rheumatoid therapies across a 28-month period.
Results
Forty cases were identified: 15% on no anti-rheumatoid treatment, 45% on mono-therapy (8 on methotrexate, 8 on prednisolone, 2 on biologics)) and 40% on combination-therapy. The total population post-operative infection rate was 18% (all superficial wound). Mean length of stay was 8.0 days (SD=6.8). Methotrexate takers had an infection rate of 5% versus 33% in non-methotrexate takers (p=0.017), and a length of stay of 6.5 days versus 9.9 days in non-MTX takers (p=0.005). Prednisolone takers had an infection rate of 37% versus 0% in non-prednisolone takers (p=0.002) and length of stay was 12.0 days versus 4.7 days in non-prednisolone takers days (p=0.006). Biologics takers had similar infection rates of 9% versus 21% in non-biologic takers (p>0.05), and a similar length of stay of 6.6 days versus 8.6 days in non-biologic takers (p>0.05).
Discussion
This data supports current evidence that methotrexate should be continued without detriment to infection risk and length of stay. Biologic agents stopped 2 weeks prior to operation appear to have no effect on infection rate and length of stay. Patients on prednisolone should be identified as at a higher risk of infection and should plan for a longer length of stay.
Conclusion
Larger scale cohort studies are required to determine whether biologic agents should be continued per-operatively.