Abstract

The goal of this research was to study trabecular bone microarchitecture during growth and development, producing new quantitative and structural knowledge about the development and remodeling of normal trabecular structure as demonstrated in a subadult archaeological skeletal sample from the Late Prehistoric Ohio Valley. Trabecular bone microarchitecture has a predictable relationship to functional and external loading patterns applied throughout ontogeny and maturity. Relatively little research has been directed toward the structure of and variation in trabecular bone during ontogeny, creating a deficiency in the foundation upon which trabecular bone adaptation can be used for bioarchaeological inferences. This research project tests hypotheses characterizing the temporal sequence and variation in trabecular bone volume fraction and degree of anisotropy as a reflection of growth and development, as associated with the timing and acquisition of normal functional activities (initial and maturation of bipedal gait), and as associated with changing body mass.

A selected skeletal sample from the Late Prehistoric site (A.D. 1200-1300) of SunWatch Village consisted of 37 subadult and three young adult proximal tibiae. The sample as a whole, as well as four maturity stage-related groups, was analyzed. The analyses consisted of nondestructive microCT scanning of the proximal metaphyseal tibia visually demonstrating the microarchitectural trabecular structure, and quantitative 3-D structural analyses measuring bone volume fraction, degree of anisotropy, trabecular thickness, and trabecular number. Bone volume fraction and degree of anisotropy are highest at birth, decreasing to a low value at one year of age, and then gradually increasing to the adult range around six to eight years of age. Trabecular number is highest at birth and lowest at skeletal maturity; trabecular thickness is lowest at birth and highest at skeletal maturity. The results of this study provide quantitative morphological and scan-image data on the ontogenetic patterned changes in human trabecular bone structure from birth to skeletal maturity, highlighting the dynamic sequential relationships between growth/development, general functional activities, and trabecular distribution/architecture.

Trabecular bone analysis is situated within the broad framework of research in musculoskeletal biology with society-wide implications in the areas of skeletal adaptation in varying genetic and environmental settings, serious public health conditions (osteoarthritis and osteoporosis), and skeletal regenerative and implant investigations. This study enhances the infrastructure of research by incorporating recent technological and methodological advances, fostering a multidisciplinary approach towards understanding skeletal biology, and augmenting relevance to biocultural studies of ancient and recent populations.