Abstract
Appendicular bone mass was measured in a series of 50 patients with non-steroid treated rheumatoid arthritis, 20 with polyarticular seronegative psoriatic arthritis, and 30 with osteoarthrosis, and compared with that of 40 controls of similar age and sex. Distal forearm bone mineral content was reduced in patients with rheumatoid and psoriatic arthritis and increased in those with osteoarthrosis. The increase in bone mass in patients with osteoarthrosis was confined to those with isolated large joint disease and was not found in those with primary generalised osteoarthrosis.