Background Total arthroscopic knee synovectomy in rheumatoid arthritis helps for successful treatment of aggressive joint synovitis and reduces cartilage and bone destruction. Inopportune and inadequate indication for surgery can lead to synovitis reccurence.

Is it possible to determine the risk factors of the synovitis recurrence using laboratory methods of diagnostics, namely serum matrix metalloproteinase-3 (MMP-3), which is one of the most popular prognostic marker in rheumatoid arthritis?

Objectives To determine the prognostic role of MMP-3 in knee joint synovitis recurrence after total arthroscopic synovectomy (TAS).

Methods The study includes 124 TAS for 108 rheumatoid arthritis patients. Serum MMP-3 was measured by ELISA before surgery and 3, 6, 12 months after. Prognostic role of MMP-3 was determined by receiver operating characteristic (ROC) curve analysis. The sensitivity, specificity, the area under the curve of ROC were calculated.

Results Serum MMP-3 levels were elevated in all RA patients compared with healthy controls. The ROC analysis showed the area under the curve of 0,751, with the specificity of 69, 2% and the sensitivity of 73, 3%. MMP-3 also correlate with arthroscopic picture of cartilage degradation (Outerbridge classification) (r=0, 44) and morphologic characteristic, such as angiomatosis, of the synovial tissue.

Conclusions High level of MMP-3 before surgery is a good predictor of the synovitis recurrence in RA. Degree of cartilage destruction and morphological characteristics of the synovial tissue are the adverse factors for the surgery results.

Disclosure of Interest None declared

DOI 10.1136/annrheumdis-2014-eular.4344