The intra-articular distribution of 90yttrium does not influence the clinical outcome of radiation synovectomy of the knee.

Objectives: To assess the impact of the intra-articular distribution of (90)yttrium-citrate ((90)Y) on the clinical effect of radiosynoviorthesis (RSO) of the knee and on (90)Y leakage from this joint.

Methods: Patients with arthritis of the knee received 185 MBq (90)Y combined with a glucocorticoid, followed by clinical bed rest. Intra-articular (90)Y distribution, measured with a dual-head gamma camera immediately or after 24 hours, was scored as mainly diffuse or mainly focal.