Subperiosteal expansion and cortical remodeling of the human femur and tibia with aging.

Increases with aging in subperiosteal dimensions and second moments of area (measures of bending and torsional rigidity) in femoral and tibial cross sections are documented in an archeological sample from the American Southwest. Significant differences between cross-sectional sites and between sexes in the pattern of cortical remodeling with age are also present. These differences appear to be related to variations in the stress or strain levels in different regions of the femur and tibia which result from in vivo mechanical loadings of the lower limb.