Osteoporotic vertebral deformities may be detected by morphometric radiography (MR) using spinal radiographs, and by morphometric X-ray absorptiometry (MXA) using dual-energy X-ray absorptiometry. Reference values for MR may not be appropriate for MXA, and reference values may be affected by gender and age. The aims of this study were to (1) compare mean deformity of vertebral height ratios for MR and MXA in men, (2) compare mean deformity for MXA in men and women, (3) compare mean wedge angle measured by MXA in men and women and (4) assess the effect of aging on MXA values in men. We studied a general practitioner sample of 115 men aged 22-81 years (mean 53 years) and 124 women aged 55-89 years (mean 68 years). Subjects had MXA of T4 to L4 using the Hologic QDR 4500A. Women and men over age 50 years had radiographs of the thoraco-lumbar spine. Scans and radiographs were marked in the same way by one operator and vertebral height ratios and mean deformity were calculated for MR and MXA. The mean wedge angle, θ, was calculated for MXA in all subjects. Mean wedge and biconcavity deformity and standard deviation (SD) in men were greater for MXA than for MR. The mean wedge and biconcavity deformity measured by MXA tended to be greater for men than for women. Vertebral deformity in men increased with age, and was associated with degenerative change seen on spinal radiographs. The mean wedge angle was greater for men than for women, and it increased with age in men. We conclude that sex- and age-specific reference ranges should be established separately for MXA.