BONE TURNOVER IN CORTICAL AND TRABECULAR BONE IN NORMAL WOMEN AND IN WOMEN WITH OSTEOPOROSIS

This study is based on the assumption that if bone turnover, shown by the uptake of (99)mTc-MDp, indicates a high rate of bone loss in patie nts with osteoporosis, it could potentially predict bone loss in patie nts at risk before significant bone loss has occurred. Methods: Quanti tative bone SPECT (QBS) using (99)mTc-MDP, expressed as the %ID/cc x 1 0(-3), was performed in 71 women who had osteoporosis in the lumbar ve rtebrae, the femoral neck or both, and in 54 age-matched normal female controls. Of the women with osteoporosis, 42 had postmenopausal osteo porosis and 29 had primary hyperparathyroidism (HPT) and osteoporosis. Results: QBS increased with age in the cortical bone and decreased in the trabecular bone of the normal women. Quantitative bone SPECT in t he femoral neck was 3.18 +/- 7.20 and was 2.73 +/- 1.06 in the femoral shaft in 20 women with postmenopausal osteoporosis of the femoral nec k. In 1 9 women with HPT and osteoporosis of the femoral neck, the QBS value in the femoral neck was 3.57 +/- 0.92 and in the femoral shaft 3.38 +/- 1.12. These values were also significantly higher for the fem oral neck and for the femoral shaft than those of normals. Although QB S values were higher in the lumbar region in 39 women with postmenopau sal osteoporosis (4.59 +/- 1.45) and in 27 women with HPT (4.30 +/- 1. 52), as compared with the normal group (4.28 +/- 1.61), the difference was not statistically significant. Conclusion: This study shows that bone turnover is significantly higher in the cortical bone of women wi th osteoporosis than in normal women.