[The treatment of gonarthritis with yttrium-90]

200 patients with gonarthritis--142 patients with rheumatoid arthritis, 38 patients with psoriatic arthritis, 7 patients with ankylosing spondylarthritis, 2 patients with collagenosis, 2 patients with antero-arthritis, 2 patients with hemophilia and 7 patients with gonarthrosis were treated with yttrium-90--4-5 mCi intra-articularly. All patients were with high activity of the process and were in the I up to the III roentgenologic stage. The results in 81.25% of the 80 patients with rheumatoid arthritis I and II stage and in 62.57% of the 62 patients in the III stage were considered "very good" and "good". Since the results in these groups are very close and the differences are insignificant it could assumed that synoviorthesis is a useful method also in the III stage of rheumatoid arthritis. The results in the other types of arthritis were favourable in 79.8% of the patients treated, i. e. they are similar to those in rheumatoid arthritis. This allows the assumption that synoviorthesis is a universal method for local treatment of all types of arthritis. The follow up of the patients for one year established a reliable reduction of the articular edema and improvement of the joint movements.