Radiation synovectomy of the ankle, knee and upper extremity joints

Abstract

Purpose: To analyse the clinical effect of radiation synovectomy or radiosynoviorthesis (RSO) of the ankle, knee and the upper extremity joints with 90Yttrium, 169Erbium, and 186Rhenium colloids. Leakage and distribution of the radionuclide are analyzed and their effect on the effectiveness of RSO. Methods: Retrospectively the effect of RSO of the ankle is analysed. The effect of RSO of upper extremity joints are analysed in a randomised, double-blind, placebo-controlled study. Prospectively, the influence of leakage on the clinical effect of RSO of upper extremity joints is analysed. As part of a Dutch multicentre clinical trial the effects of intra-articular 90Yttrium distribution on the clinical effect of RSO of the knee and on leakage from the joint are analysed. In a systematic review of the literature the clinical effect of RSO is analysed. Results: RSO of the ankle is effective in 78%, although all patients eventually experience recurrence of arthritis. Leakage is generally quite low and RSO is save. RSO treatment of upper extremity joints with radionuclide plus glucocorticoid (GC) (group A) shows a significantly higher response rate compared to that of placebo plus GC (group B). At 6 months, the response rate is 69% (25/36) in group A and 29% (9/31) in group B (p=0.001) and at 12 months 69% (25/36) in group A and 32% (8/25) in group B (p=0.004), respectively. Leakage from the joint does not negatively influence the effect of RSO. The mean leakage to the lymph nodes is 1.7 2.7% of the injected dose (range 0-9.9%). The median leakage to liver/spleen is 0.2% (range 0-6.8%). Leakage is detectable in 5 of the 11 non-responders (45%), and in 20 of the 25 responders (80%) (p=0.06). Only the patient’s age at the time of the injection can predict leakage. Intra-articular 90Yttrium distribution does not influence the clinical effect of RSO of the knee. 90Yttrium is “mainly diffuse” in 54% of the joints and “mainly focal” in 46%: response rate is 40% for the “mainly diffuse” distribution group and 56% for the “mainly focal” distribution group. Similarly, leakage have no (adverse) effect on the clinical results. RSO of the knee is effective in approximately 50%.The reported success rates of 169Erbium-RSO and 186Rhenium-RSO ranges from 54-100%; for 90Yttrium, the success rates are 24-100%. At 6 months, the pooled odds ratio favouring RSO of the knee with 90Yttrium over GC or saline is 4 (CI 95% 1.2-14; p=0.02), and at 12 months the ratio is 1.7 (CI 95% 0.69-4; p=0.26). For RSO of small joints with 169Erbium or 186Rhenium the pooled odds ratio at 6 months is 2 (CI 95% 0.66-6; p=0.22), and at 12 months, it is 2 (CI 95% 1.09-3.5; p=0.03). Conclusion: RSO of the ankle and upper extremity joints is effective; RSO of the knee is less effective. RSO of the upper extremity joints can be recommended in persistent synovitis after failure to an outpatient intra-articular GC injection. Leakage and inhomogeneous distribution seem clinically not important and do not impair the effect of RSO.