Physical activity, cystic erosions, and osteoporosis in rheumatoid arthritis.

Abstract
Hand radiographs from 153 patients with rheumatoid arthritis indicated that there is a close relationship between the degree of physical activity and the development of large cystic erosions. These 2 factors are inversely related to osteoporosis. Cystic erosions are seen more often in men, who perform higher grades of manual activity than women.