A prospective observational study on the long-term results of 90Yttrium citrate radiosynoviorthesis of synovitis in osteoarthritis of the knee joint.

Abstract

Radiosynoviorthesis (RSO) is used for the treatment of inflammatory joint diseases. However, there are no long-term results published comparing it to conservative therapy. Therefore, the aim of this prospective observational study was to evaluate response rates after radionuclide therapy in patients suffering from knee osteoarthritis over a time period of 10years. Radionuclide therapy with intra-articular administration of colloidal 90Yttrium citrate was performed in osteoarthritic patients [Kellgren-Lawrence grades I/II (n = 69) and Kellgren-Lawrence grade III (n = 72)]. In patients with early-stage disease, an excellent/good response with respect to pain, joint mobility, and function was observed in 82.5% for 1year and in 73.7% for 8years after therapy. Responses declined to 50% at 10years post treatment. In grade III patients, an excellent/good response was observed in 45.9%; a decline to 41.2% was observed in the first 8years. In this group, the number of patients available for follow-up after 9 and 10years dropped significantly from 51 patients after 8years to only 30 patients after 9years, and to nine patients after 10years. As a result, these response rates were not appraisable. Long-term results of radiosynoviorthesis in knee osteoarthritis are excellent/good in many patients. The response rate depends on Kellgren-Lawrence stages, and early-stage radionuclide therapy for osteoarthritis is suggested.