The relationship between phalangeal bone density and vertebral deformities

Radiographic absorptiometry (RA) of the phalanges is a convenient and relia ble technique for measuring bone mineral density (BMD). It needs only a rad iograph of the hand, which can be sent for evaluation to a central facility , whereas other techniques require specialized equipment. We assessed the r elationship between RA measurements and the presence of vertebral deformiti es in a population-based cohort of postmenopausal women, and to compare the results with simultaneously obtained BMD of the hip by dual-energy X-ray a bsorptiometry (DXA). A total of 389 women aged 55-84 (mean age 67.2 years, SD 8.7) were randomly selected from a large general practice. RA, DXA of th e hip, and vertebral deformities in the lateral spine X-rays by vertebral m orphometry were assessed. Thirty-eight women (9.8%) had severe (grade Il) v ertebral deformities, and their BMD at the phalanges and femoral neck was s ignificantly lower than that of women without severe vertebral deformities. Odds ratios for the presence of severe vertebral deformities of 1.5 (95% C I: 1.1-2.1) for RA and 1.3 (95% CI: 0.9-1.9) for DXA, together with similar receiver operating characteristics curves, were found using age-adjusted l ogistic regression. Phalangeal BMD is related to vertebral deformities at l east as closely as BMD of the femoral neck BMD. RA may therefore help to ev aluate fracture risk, especially if no DXA equipment is available.