Objective measurement of rheumatoid arthritis using technetium index.

The technetium index was measured in 22 patients with rheumatoid arthritis, before and after 6 months' treatment either with penicillamine or with anti-inflammatory drugs. The index was calculated by dividing the sum of the count rates over both knees and both wrists by the dose of technetium given. In the penicillamine group there was a significant reduction in the technetium index and the changes correlated well with some clinical measurements of improvement. It is suggested that the technetium index is a useful objective measure of the effects of drugs with a specific activity in rheumatoid arthritis.