Meeting Abstract
33.1 Tuesday, Jan. 5 The structure-function relationship in bone microstructure: An experimental study in Helmeted GuineaFowl (Numida meleagris) DE BOEF, M.**; BIEWENER, A. A.; Concord Field Station, Harvard University; Concord Field Station, Harvard University maria.deboef@gmail.com
It has been well established that bone macrostructural morphology is strongly influenced by bone function. This relationship is evident not only in the how bones with different functions are structured but also in how bone structure adapts to changes in loading patterns. Several studies have found that this strong structure-function relationship extends to bone microstructural morphology as well. However, the precise relationship between the various microstructure morphologies and types (tensile, compressive or shear) and magnitudes of bone strain has not yet become clear. In this study, Helmeted GuineaFowl (Numida meleagris) were exposed to flight and running exercise during development. The types and magnitudes of strain experienced by the humerus and tibiotarsus were quantified and compared to the bone microstructure found in these bones. Bone microstructure was characterized using measures of vascular orientation and osteocyte density. It was found that significant differences in these bone microstructure characteristics existed between skeletal elements and between exercised and control birds. Vascular canals in the tibiotarsus were primarily oriented along the longitudinal axis. In contrast, vascular canals in the humerus were primarily oriented within the plane of section and parallel to the periosteal surface, a pattern often described as laminar. These patterns were exaggerated in the exercised birds. Osteocyte density was higher in the tibiotarsus than in the humerus and higher in the exercised birds than in the controls. There was no correlation between bone microstructure in specific regions of a bone (medial, lateral, dorsal, ventral) and the type or magnitude of strain experienced by that region.
