Heidsieck C, Gajny L, Travert C, et al. - Alterations in global sagittal alignment observed with age were found to be consistent with the literature. In this simplified loading model, significant decrease in vertebral strength due to posture alteration with age was evident. Postural alignment appears important to be considered in the assessment of osteoporotic patients.

• From 117 individuals aged between 20 and 83 years, EOS biplane radiographs were examined to compute the upper body lever arm over the L1 vertebra and its influence on vertebral strength.

• Three age groups were analyzed: young (20 to 40 years, 62 individuals), intermediate (40 to 60 years, 26 individuals), and elderly (60 years and over, 29 individuals).

• Finite element analysis and barycentremetry were used.

• Between young and older groups, a combination of an increase in thoracic kyphosis, cervical lordosis, and pelvic tilt with a loss of lumbar lordosis was evident.

• With increasing age, a more forward position was indicated by sagittal alignment parameters.

• Variation in the lever arm of the center of mass above L1 was evident; from an average of 1 mm backward for the young group, to averages of 10 and 24 mm forward, respectively, for the intermediate and elderly group.

• Consequently, reduction in vertebral strength occurred, from 2,527 N for the young group to 1,820 N for the elderly group.