Treatment of persistent knee effusions with intra-articular radioactive gold.

Patients with a total of 112 chronic knee effusions unresponsive to the usual conservative methods of therapy were treated with intra-articular injections of radioactive gold and followed from 6 months to 5 years. Most patients in the study had rheumatoid arthritis but others had ankylosing spondylitis, psoriatic arthritis, intermittent hydrathrosis and undiagnosed synovitis. After 6 months 81% showed improvement. This figure diminished to approximately 70% at 1 and 2 years, 60% at 3 and 4 years and 50% at 5 years. The mose beneficial results were seen in patients with intermittent hydrarthrosis. Twelve patients with a synovial cyst and/or rupture improved. Patients with thin synovia and anatomic stage I or II disease did best, but those with stage III disease also did well. After the injection 33% of the patients had a reactive synovitis. A variable amount of radioactive material escaped from the knee to the regional lymph nodes and general circulation.