Finite element analysis of tibial fractures.

INTRODUCTION Fractures of the tibial shaft are relatively common injuries. There are indications that tibial shaft fractures share characteristics in terms of site, type and local fracture mechanisms. In this study, we aimed to set up a mathematical, computer-based model using finite element analysis of the bones of the lower leg to examine if such a model is adequate for prediction of fracture locations and patterns. In future studies, we aim to use these biomechanical results to examine fracture prevention, among others, and to simulate different types of osteosynthesis and the process of bony healing. The biomechanical results are the basis for fracture healing, biomechanical fall analysis and stability analysis of osteosynthesis. MATERIAL AND METHODS A finite element model of the bony part of the lower leg was generated on the basis of computed tomography data from the Visible Human Project. The data consisted of 21,219 3D elements with a cortical shell and a trabecular core. Three types of load of torsion, a direct lateral load and axial compression were applied. RESULTS The finite element linear static analysis resulted in relevant fracture localizations and indicated relevant fracture patterns. CONCLUSION In the present study, we have successfully simulated fracture mechanisms, obtained adequate fracture locations and achieved an indication of the fracture morphology. The method of fracture simulation employed showed good agreement with known clinical data and data from prior mechanical testing. This substantiates the validity of fracture simulation for future studies examining tibial fractures, fracture healing and prevention.

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