THU0247 What is a Risk Factor for the Knee Synovitis Recurrence after an Arthroscopic Synovectomy in a Patient with Rheumatoid Arthritis?

Background

Arthroscopic knee synovectomy (AKS) is the most popular surgery treatment for persistent knee synovitis among patients with rheumatoid arthritis (RA).

Objectives

To assess the probability of knee synovitis recurrence during the postoperative period dependings upon disease activity and whether or not the patient receiveings disease–modifying anti–rheumatic drugs (DMARDs).

Methods

124 AKS for 108 rheumatoid arthritis patients were made. The average period of assessment was 4.5 ± 2.5 years, the average patient’s age was 41.7 ± 14.3 years. After AKS there were clinical symptoms of synovitis recurrence in 20% of cases (25 knees), after an average period of 10.8 ± 5.1 months (i.e. from 0.5 to 2 years). The first prescription of DMARDsfor these patients was quite late: after 3.5 ± 1.8 years since the beginning of the disease. The treatment with the DMARDswas short and unsystematic. Usually patients with the synovitis recurrence were treated with methotrexate in maximum doses of 10 mg per week. 36% of the patients were treated with glucocorticoids. 28% of the patients were treated with the biological disease-modifying antirheumatic drugs (infliximab). 12.8% of the synovitis recurrence in the knees after surgery was diagnosed at the same time as the RA exacerbations. Before surgery, the disease activity in rheumatoid arthritis was high: 12.7 ± 5.4 in Routine Assessment of Pain Index Data (RAPID-3). Cox’s F-Test and Kaplan-Maier`s curve were used to determine differences in the likelihood of the synovitis recurrence, depending on the availability of therapy. Assessment of the prognostic significance of RA was made by ROC- curve analysis.

Results

In the case of absence of matched DMARDs by the 24th month after the surgery, the synovitis recurrence appeared in more than 80% of the patients (Cox’s F-Test = 11.69495, p<10^-5). For values ​​of the RAPID-3 index above 11.7 points with 86% sensitivity and 74.4% specificity predicted recurrence of synovitis in the following year.

Conclusions

DMARDs and high activity of RA are considered as risk factors for the knee synovitis recurrence after the AKS.

Disclosure of Interest

None Declared