Understanding the biomechanics of the middle ear is important for surgical reconstructions. As the output of the
middle ear, the stapes plays a key role in transferring acoustic vibrations to the cochlea. In order to develop anatomically-based mathematical models, which are needed to improve our understanding of stapes dynamics, detailed morphometry
of the stapes is required. High-resolution micro-CT imaging techniques were used to generate three-dimensional
reconstructions of cadaveric temporal bones from 5 species commonly used in experimental middle ear research: the
chinchilla, human (relatively mid-frequency hearing limit), cat, guinea pig, and gerbil (relatively high-frequency hearing
limit). From the standard discretizations of micro-CT images and corresponding 3-D volume reconstructions, the centers
of mass, principle axes, stapes head areas and stapes footplate areas were calculated. Mechanical relationships were
estimated between the capitulum area and the footplate area and inter-species comparisons were performed between the
cross-sectional shapes of the anterior and posterior crura. Quantitative dynamic properties were estimated from the rigid
body motion calculations. The parameters estimated in this study will be useful for building biocomputational models of
the stapes for a variety of species.
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