Doctor of Philosophy, The Ohio State University, 2017, Anthropology
The objective of this research was to test the hypotheses that ontogenetic patterns of change in tibial subchondral trabecular and cortical bone microstructure are age and condyle site-specific due to differential loading associated with changing joint kinetics and body mass. High-resolution computed tomography (HR-CT) images were acquired for 31 human tibiae, ranging in age from 8 to 37.5 years. The skeletal samples are from Norris Farms #36 site, a cemetery mound in the central Illinois River valley associated with the Oneota culture, dating to A.D. 1300. This bioarchaeological sample was chosen for this study because of its cultural and biological homogeneity, high number of subadult individuals, extensive archaeological context, and excellent preservation. Proximal epiphyses were digitally isolated for analysis as regions of interest (ROIs) using Avizo Fire 6.2 and 8.1.1. 3D resolution-corrected morphometric analysis of subchondral bone architecture was performed for 11 cubic volumes of interest (VOIs) using the BoneJ plugin for ImageJ. VOIs were positioned within and between the tibial condyles within the epiphyseal region. The analysis of the subchondral cortical plate was accomplished through dual-threshold cortical masking.
Ontogenetic patterns in the epiphysis of the proximal tibia were described using eight 3D morphological parameters: bone volume fraction (BV/TV), mean trabecular thickness (Tb.Th), mean trabecular spacing (Tb.Sp), structure model index (SMI), connectivity density (Conn.D), degree of anisotropy (DA), trabecular number (Tb.N), and cortical thickness (Ct.Th) in the subchondral cortical plate. Kruskal-Wallis and Wilcoxon signed rank tests were used to examine the association between region, age, and each of the eight structural parameters. For analysis, individuals were divided into four age categories: child, adolescent, young adult, and middle age. The findings of this study indicate that age-related changes in mechanical loading have (open full item for complete abstract)
Committee: Samuel Stout PhD (Advisor); James Gosman M.D, PhD (Committee Member); Mark Hubbe PhD (Committee Member); Clark Larsen PhD (Committee Member); Scott McGraw PhD (Committee Member)
Subjects: Aging; Anatomy and Physiology; Archaeology; Behavioral Sciences; Biology; Biomechanics; Evolution and Development; Microbiology