Complementary Role of Simple Radiography and Bone Mineral Density on Diagnosis of Osteoporosis

Abstract

Objectives: Osteoporosis has been a serious problem in an aging society. Measurement of the bone mineral density by dual-energy X-ray absorptiometry is now accepted as a standard method for evaluation of osteoporosis. But degenerative changes commonly noted in elderly people may affect their bone mineral density. So the objective of this study was to compare the role of radiographic abnormality with bone mineral density on the diagnosis of osteoporosis. Methods: This study included 1082 patients visited the Ajou University Hospital from October 2004 to January 2005. First bone mineral density reading was done by only densitometry(Dual Energy X-ray absorptiometry: DP Expert XL: Lunar, USA), and second reading was done by both simple radiography and densitometry. The osteoporosis was diagnosed by WHO criteria. Results: The prevalence of normal were 412 cases(38.08%), osteopenia were 373 cases(34.47%), osteoporosis were 199 cases(18.39%), osteoporosis with fracture were 87 cases(8.04%), and unable to diagnose were 11 cases(1.02%) at the first reading. On the other hand, the prevalence of normal were 406 cases(37.52%), osteopenia were 349 cases(32.26%), osteoporosis were 185 cases(17.10%), osteoporosis with fractures were 131 cases(12.10%), and unable to diagnose were 11 cases(1.02%) at the second reading. After second reading, the incidence of switching diagnosis was 3.14% in normal group, 13.67% in osteopenia group, 16.08% in osteoporosis group, and 4.06% in osteoporosis with fracture group. Vertebral fracture rate was 8.04% at the first reading, but increased as 12.10% at the second reading. The most common fracture site was L1. The most common degenerative change site was L4. Conclusion: These results show that bone densitometry results should be complemented with simple x-ray of the spine region for the accuracy of diagnosis.