Bone density in women: A modified procedure for measurement of distal radial density

Abstract
This is a cross‐sectional study of bone densitometry in >700 normal healthy white women ranging in age from 18 to 98 years. A modified procedure for single–photon bone density analysis of the distal radius is described and compared with dual‐photon densitometric measurements of the second through fourth lumbar vertebrae. The distal radial site measured was separated from the ulna by 5 mm. This “5 mm” site was characterized according to trabecular and cortical bone content, measurement reproducibility, positioning precision, and the effects of wrist pronation or supination. The radial site demonstrated a bone density loss of <0.1%/year for normal women 25–50 years of age, increasing to 0.7%/year after 50 years of age. In contrast to the variability and inconsistency obtained by us and others utilizing the standard “9/10” site, bone loss with age at the new “5 mm” site correlated closely with generalized bone mineral loss of the axial skeleton. We suggest that there is a unique role for single‐beam densitometric measurements of the radius, permitting the rapid and relatively inexpensive evaluation of large populations of women without requiring a visit to a medical center. Such a process can select those requiring further evaluation or medical attention.