VERTEBRAL MORPHOMETRY IN WOMEN AGED 50-81 YEARS

Vertebral dimensions and vertebral shape indices (VSI) were investigat ed in T4-L4 in 926 females aged 50-81 years. The most consistent findi ng was the increase of inferior antero-posterior dimension with age. W edging and concavity also increased with age but the changes were not significant at all vertebral levels, The value of VSIs also varied wit h level. Thus a particular degree of VSI, considered normal at one lev el or at one age, would be outside the reference range at a different level or age group. The number of subjects identified as osteoporotic by skewness (5.4%) or in excess of three standard deviations from the mean (6.5%) was much lower than in recent reports from North America. The number of subjects contributing to a skewed distribution increased with age from 0.5% at 55-59 years to 10.0% at 75-79 years. Change wit h age in the antero-posterior dimension could increase load-bearing ar ea in older subjects, but the decline in bone density will be increase d as a declining bone mineral content occupies a larger volume.