BONE TURNOVER IN NONSTEROID TREATED RHEUMATOID-ARTHRITIS

Objective-To examine whether changes in cancellous bone turnover and resorption cavity depth contribute to bone loss in patients with non-steroid treated rheumatoid arthritis. Methods-Iliac crest biopsies were obtained from 37 patients with non-steroid treated rheumatoid arthritis, 13 male and 24 female, aged 37-71 years. Bone turnover and resorption cavity characteristics were quantitatively assessed using semiautomated computerised techniques. Results-When compared with age- and sex-matched control values, there was a significant reduction in bone formation rate at tissue level and activation frequency (P < 0.001) in the patient group. The eroded perimeter, mean and maximum eroded depth and cavity area were also significantly reduced (P < 0.01, <0.005, <0.001 and <0.005 respectively). Conclusion-These results demonstrate low bone turnover in non-steroid treated rheumatoid arthritis and indicate that the reduced bone mass in these patients is due mainly to a negative remodelling balance.