Comparison of Bi-planar Radiography and Adjusted Scaling Equations for the Computation of Appropriate 3D Body Segment Inertial Parameters

The Body Segments Inertial Parameters (BSIPs) are essential data in biomechanics. However, the measurements on cadaver are restrictive and the measurements on living human remain limiting. Moreover, in the literature, the predictive equations are mainly 2D and include two restraining assumptions. Accordingly, it is still challenging to obtain appropriate 3D BSIPs. A bi-planar radiographic method, previously developed to obtain personalized BSIPs, and adjusted scaling equations, recently developed to provide the 3D position of the center of mass and both moments and products of inertia, were compared and demonstrated the same mass distribution (although significant differences). The center of mass was slightly posterior and lateral, and the products of inertia were almost of the same order as the longitudinal moment of inertia. These data may be useful for researchers who would like to obtain appropriate 3D BSIPs.