[Results of radiosynoviorthesis with yttrium 90 in chronic synovitis: a long-term prospective study. II. Effect of general disease parameters]

The results of 193 Yttrium-90 synovectomies in 174 knee joints and 19 shoulder joints, mostly in patients with rheumatoid arthritis, were analysed statistically on the basis of 6 monthly reinvestigations up to a follow up of three years. The results were significantly better in stage I than in stages II-IV of rheumatoid arthritis, which did not differ between each other; they were better in patients with low than in those with high disease activity; the effectivity was better in patients who responded well to medical treatment than in those who responded badly. In the group with "good" results of Y-90 synovectomy a significant fall in sedimentation rate and significant rise of hemoglobin could be registered. On the other hand, there was no difference between seropositive and seronegative patients. In a number of joints the good result of radiation synovectomy was preserved even in patients with overall progression of the disease. Our results show that the results of radiation synovectomy as of all local treatments have to be regarded in relation to the general development of the disease.