Development of a kinematic 3D carpal model to analyze in vivo soft-tissue interaction across multiple static postures

Abstract

We developed a subject-specific kinematic model to analyze in vivo soft-tissue interaction in the carpus in static, unloaded postures. The bone geometry was extracted from a reference computed tomography volume image. The soft-tissue geometry, including cartilage and ligament tissues, was computationally modeled based on kinematic constraints; the constraints were extracted from multiple computed tomography scans corresponding to different carpal postures. The data collected in vivo was next coupled with numerical simulation in order to analyze the role of soft-tissues in different postures. The resulting model extends the state of biomecanical modeling by incorporating soft-tissue constraints across the carpus range of motion, while successfully using only physiological constraints. The model results suggest that soft-tissue wrapping constraints have substantial impact on carpus stability.

Functional kinematics of the wrist

“…Finally, the functional methods reviewed here are unable to measure cartilage contact and ligament forces. Computational modelling is a promising approach that can overcome this limitation by estimating these forces, but most studies to date have focused on model validation with low subject numbers (Carrigan et al, 2003; Fischli et al, 2009; Marai et al, 2009; Schuind et al, 1995). An additional limitation of computational models is that model assumptions, tuning of parameters, model validation, and hypothesis testing are challenging to separate.…”

Biomechanical Finite Element Method Model of the Proximal Carpal Row and Experimental Validation

“…After the triangular 2D mesh is done and the element triangle shapes accomplish the previous rules, we had to transform this 2D mesh into a 3D one. According to the bibliography and the background, we can find about FEM models in the biomedical area (Carrigan et al, 2003 ; Marai et al, 2009 ; Gíslason et al, 2010 ; Gíslason and Nash, 2012 ; Mohd Nazri Bajuri, 2013 ), there are two main types of elements that have been widely used: tetrahedral and hexahedral. Hexahedral elements were less efficient than tetrahedral in contact analysis due to the high number of nodes (more tendency to distort).…”