OBJECTIVES To determine whether continued methotrexate treatment increases the risk of postoperative infections or of surgical complications in patients with rheumatoid arthritis (RA) within one year of elective orthopaedic surgery.

DESIGN A prospective randomised study of postoperative infection or surgical complications occurring within one year of surgery in patients with RA who underwent elective orthopaedic surgery.

SUBJECTS 388 patients with RA who were to undergo elective orthopaedic surgery. Patients who were receiving methotrexate were randomly allocated to groups who either continued methotrexate (group A) or who discontinued methotrexate from two weeks before surgery until two weeks after surgery (group B). Their complication rates were compared with complications occurring in 228 patients with RA (group C) who were not receiving methotrexate and who also underwent elective orthopaedic surgery.

MAIN OUTCOME MEASURES Signs of postoperative infection were recorded, including rubor, discharge, systemic infection, and frequency of wound dehiscence as well as the incidence of any surgical complication requiring a secondary revision procedure that occurred within one year of surgery. The frequencies of flare up activity of RA at six weeks and six months after surgery were also recorded. A flare of rheumatoid disease was defined as an increase in joint pain in two or more joints notified by the patient as well as by an increase in articular index of at least 25% after surgery.

RESULTS Signs of infection or surgical complications occurred in two of 88 procedures in group A (2%), 11 of 72 procedures in group B (15%), and 24 of 228 (10.5%) procedures in group C. The surgical complication or infection frequency in group A was less than that in either group B (p<0.003) or group C (p=0.026). At six weeks after surgery there were no flares in group A, six flares in group B (8%), and six flares in group C (2.6%). Logistic regression analysis of the overall surgical complication rate in all the patients with RA studied showed that methotrexate, whether continued or discontinued before surgery, did not increase the early complication rate in the patients with RA who underwent elective orthopaedic surgery. Other drugs—penicillamine, indometacin, cyclosporin, hydroxychloroquine, chloroquine, and prednisolone—all did significantly increase the risk of infection or surgical complication after elective orthopaedic surgery. The risk of surgery was also increased in the presence of intercurrent chronic diseases—diabetes, hypertension, bronchiectasis, psoriasis, asthma, and ischaemic heart disease.

CONCLUSION Continuation of methotrexate treatment does not increase the risk of either infections or of surgical complications occurring in patients with RA within one year of elective orthopaedic surgery. Thus methotrexate treatment should not be stopped in patients whose disease is controlled by the drug before elective orthopaedic surgery.