Intraskeletal Variability of Relative Cortical Area in Humans.

Instituto de Investigaciones Arqueologicas y Museo, Universidad Catolica del Norte,San Pedro de Atacama, ChileABSTRACTHistomorphometric and cross-sectional geometric studies of bonehave provided valuable information about age at death, behavioral andactivity patterns, and pathological conditions for past and present humanpopulations. While a considerable amount of exploratory and appliedresearch has been completed using histomorphometric and cross-sectionalgeometric properties, the effects of intraskeletal variability on interpret-ing observed histomorphometric data have not been fully explored. Thepurpose of this study is to quantify intraskeletal variability in the relativecortical area of long bones and ribs from modern humans. To examineintraskeletal variability, cross-sections of the femur, tibia, fibula,humerus, radius, ulna, and rib when present, were examined within indi-viduals from a cadaveric collection (N534). Relative cortical area wascompared within individuals using a repeated measurements GeneralLinear Model, which shows significant differences between bones, particu-larly between the rib and the remaining long bones. Complementarily,correlations between bones’ relative cortical area values suggest animportant allometric component affecting this aspect of long bones, butnot of the rib. This study highlights the magnitude of intraskeletal vari-ability in relative cortical area in the human skeleton, and because therelative cortical area of any particular bone is affected by a series of con-founding factors, extrapolation of relative cortical area values to inferload history for other skeletal elements can be misleading. Anat Rec,00:000–000, 2015.