Radio-synovectomy in chronic synovitis of the knee joint in patients with rheumatoid arthritis.

The influence of intra-articular (i.a.) colloidal 198Au (5 mCi) or 90Y-silicate (5 mCi) on synovitis of the knee joint in patients older than 45 years with rheumatoid arthritis (RA), who had been treated since 1970 in our hospital, was investigated. Of the 89 knee joints of 77 patients studied, 65 had no or minimal radiological abnormalities of the knee joint treated (group I), whereas 24 patients had moderate to severe changes (group II). Before and at regular intervals after radio-synovectomy the clinical response was scored using pain, hydrops and warmth as parameters. The results indicated that 1 year after treatment the percentage of knee joints with a favourable response was greater in group I than in group II (58% versus 25%, P = 0.001). This difference was still present 3 years after treatment. Clinical response showed no correlation with initial inflammatory activity as measured by 99mTc-pertechnetate uptake measurements. However, in group I, those patients with an ESR below 60 mm/h, measured just before radio-synovectomy, more often had a favourable response than those with an ESR in excess of 60 mm/h (P = 0.01). No or only slight complications of radio-synovectomy were noted, whereas leakage of radioactivity from the knee joints was minimal. It is concluded that radio-synovectomy is an effective and safe procedure in those patients with rheumatoid synovitis of the knee joint without the presence of significant radiological damage and the absence of active systemic disease.