1Department of Anthropology, Pennsylvania State University, 2Center for Quantitative Imaging, EMS Energy Institute, Pennsylvania State University, 3School of Anthropology, University of Arizona, 4Department of Anthropology, Ohio State University
Saturday All day, Clinch Concourse
The objective of this research is to examine how human locomotor development contributes to the pattern of ontogenetic morphological change in trabecular microarchitecture and adjacent cortical geometry. The hypothesis tested predicts that the pattern of ontogenetic within-tibial variability in trabecular and cortical bone is associated with age-related variability in gait kinematics. High-resolution CT scans were collected for the tibia from the Norris Farms #36 skeletal collection, ranging in age from neonate to adult. Resolution-corrected morphometric structural analysis of the 3D trabecular bone fabric structure was performed for multiple cubic volumes of interest from the proximal and distal tibial metaphyses using the BoneJ plugin within ImageJ. Cortical cross-sectional geometric parameters were calculated at 20% and 80% of whole bone length. Gait analyses were undertaken on 25 age-grouped children between the ages of 1 and 9 years to establish new data for joint kinematics/kinetics coefficients of variation (CV) across age classes. The results of this work demonstrate that individual CVs versus age for joint angles are significant in the medial/lateral axis at the knee and ankle with the greatest variability in the youngest. Multivariate analysis supports the hypothesis of increased trabecular bone microarchitectural variability in the younger ages at both the proximal and distal tibia. Age-related cortical bone variability is significant in the proximal tibia, but not distal. Our conclusions from these data support the concept that the kinematic characteristics associated with the initiation of human gait contribute to skeletal microarchitectural and geometrical heterogeneity and differentiation.
Grant support: NSF BCS-1028904 (DAR, TMR, and JHG)