Diseño de modelado numérico para optimización de ubicación de puntos de fijación en implantes craneales

Abstract

CONDITION FOR PUBLICATION OF PROJECT. This project develops an algorithm for determining the optimal locations of fixation points in cranial implants, integrating engineering-based criteria to increase the structural safety of the implant-fixation assembly, with aim of supporting clinical expertise. The central hypothesis is that evaluating all possible anchorage combinations, based on stress analysis and safety factors, makes it possible to identify more reliable configurations than empirical selections, particularly when considering materials manufactured through additive manufacturing. The methodology was developed using Autodesk Fusion, where the point cloud was extracted and classified into safe zones according to medical criteria; a Python-based code was used to fit the data to a representative surface through radial basis function (RBF) interpolation to estimate surface-normal directions of the implant. In parallel, the reaction loads for each anchorage combination were obtained through the combined use of Python and Autodesk Inventor Nastran, employing finite element analysis (FEA) static simulations under an applied external force of 50 N, resulting in a total of 1728 evaluated combinations. As a result, the algorithm outputs all critical safety factors and a preferential failure criterion, additionally quantifying a robustness percentage for a total of eight patient specific implants. In conclusion, the proposed methodology constitutes a reproducible and verifiable basis for recommending fixation points with greater safety and consistency across patients. Keywords: Cranioplasty, cranial screws, finite element analysis, RBF interpolation, Autodesk Inventor Nastran