Changes in the concentration of plasma matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases-1 (TIMP-1) after total joint replacement in patients with arthritis.

Matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) have been reported to be associated with arthritis. Total joint replacement results in total resection of cartilage and synovium at the joint. We investigated longitudinal changes in plasma MMP and TIMP after total joint replacement. Eight patients with osteoarthritis (OA) and 15 patients with rheumatoid arthritis (RA) had total knee or total hip replacements. Plasma was collected from all patients before surgery and at 1 week and 6 weeks after surgery. In RA patients the plasma MMP-3 and the MMP-3/TIMP-1 ratio decreased after total joint replacement, whereas CRP and ESR did not change. Therefore, CRP and ESR reflect systemic inflammation; however, plasma MMP-3 and the MMP-3/TIMP-1 ratio may reflect inflammation and/or degeneration of the affected joint.