To What Extent Do Disease-Modifying Anti-rheumatic Drugs Affect Bone Union in Trauma and Orthopaedic Patients?

Patients with rheumatoid arthritis have an increased risk of postoperative complications in orthopaedic surgery because of the effect of the disease on bone as well as the immunomodulatory medications that can interfere with bone healing. Our literature review aims to synthesise current literature on disease-modifying anti-rheumatic drugs (DMARDs) available to aid decision-making in withholding or continuing these medications in the perioperative period. A literature search was conducted on Embase, PubMed, and MEDLINE. The initial search around foot and ankle osteotomies and DMARDs only yielded four original papers. After expanding our search to include trauma and elective procedures, the search yielded 80 papers. In total, nine papers were included for review after applying our inclusion and exclusion criteria. Methotrexate (MTX) appears to have a dose-dependent effect on bone healing with lower doses used in rheumatoid patients showing no adverse effect on bone healing. In spinal surgery, those who continued DMARDs had greater radiographic fusion outcomes and fewer disease flares compared to those who discontinued the drug. Biologic medications, however, showed adverse effects on bone healing and carried a higher rate of revision surgery. Our review has highlighted an important literature gap on the effects of DMARDs on bone union. The main finding from the review is that continuing conventional DMARDs in the perioperative period for joint surgery appears safe, but biologics should be held for at least two weeks or until there are signs of wound healing.