Therapeutic status of radiosynoviorthesis of the knee with yttrium [90Y] colloid in rheumatoid arthritis and related indications.

Radiosynoviorthesis (RSO) with an yttrium-90 colloid offers a local and minimally invasive therapy for treating inflammatory hypertrophy of the synovial membrane of the knee that has arisen from numerous kinds of disorder: these include rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthropathy, villonodular synovitis and others. There is substantial evidence that this treatment is efficacious and that, in view of the benefits that it offers, its tolerability and safety are very good. Administration should be restricted to patients in whom other therapies (including locally injected corticoids) have failed, and proper attention must be paid to correct administration, including post-treatment immobilization and the co-administration of corticoids, to minimize the risk of leakage and of efflux through the puncture channel.