Acta Vet. Brno 2010, 79: 621-626
Mathematical Modelling of Crack Fractography after Implant Failure of Titanium 4.5 LCP Used for Flexible Bridging Osteosynthesis in a Miniature Pig
Biomechanics of fracture fixation and testing of mechanical properties of bone/implant construct from the viewpoint of checking the strength and resistance ability to acting forces are of current interest. Computer modelling known as mathematical modelling is regarded as an alternative to mechanical testing of properties on a testing machine. As a result, we get a 3D model of a real object (i.e., implant for fracture fixation in our case), which can be exposed to deformation processes in the environment of the mathematical software in order to characterize forces acting on the implant and subsequently analyze the forces causing the implant failure (broken plate). The goal of this study was to employ mathematical-statistical modelling for determination of forces that caused failure (broken implant) of a five-hole titanium 4.5 mm Locking Compression Plate. This plate has been used for flexible bridging osteosynthesis of segmental femoral diaphyseal defect in a miniature pig to investigate bone healing after transplantation of mesenchymal stem cells in combination with biocompatible scaffolds. Mathematical modelling has been performed with COMSOL Multiphysics software. Numerical study that describes deformation processes taking place in implant failure demonstrates the possibilities of deformation of five-hole titanium 4.5 mm LCP in the case of exceeding the elastic limits of a material. Knowledge of the forces acting on implants used for fracture fixation acquired from mathematical modelling might be used in clinical practice in order to prevent undesirable implant failure.
Keywords
Plate, bone defect, fracture, deformation, crack driving face, stress field.
