A Method for Estimating Biomechanical Parameters of Upper and Lower Extremities 2008-01-1919

The purpose of this study is to estimate the biomechanical parameters (BPs) of the upper and lower extremities of human body. These parameters include mass, center of mass, density, moment of inertia and radius of gyration. The method is desired to acquire 3D mass profile of the extremity by mapping 3D tomographical data obtained from computerized tomography scan (CT) onto 3D scanned data.

The surface data of the segment is dissected into several equally-spaced cross-sections along its longitudinal axis like those of the CT tomographical scan. For each pair of cross-sections, the profile of the tomographical data is superimposed on the surface data, registered and aligned. The bone is mapped first without any deformation. The skin of tomographical cross-section is deformed to the surface contour, as well as the boundary of muscle. Then the area of the deformed muscle is rescaled in order to pertain to the same size as that of the tomographical data. The area bound between the skin and the muscle is considered as fat. The profile of tissues of with 4 different densities forming new cross-section, is employed to calculate the mass distribution profile of the cross-section.

Upon the completion of all the distribution profiles for the segment, these cross-sections are used to re-construct a segment of solid. The final solid segment is then finally dissected into infinitesimal solid lattices of mass distribution for the computation of BPs.