Biomechanika - Zevní a vnitřní fixátory pro léčbu různých typů komplikovaných zlomenin kostí

Abstract

This dissertation thesis deals with the strength and stiffness analysis of internal and external fixators which are used in the treatment of bone fractures by osteosynthesis (traumatology). The beginning of the dissertation describes the anatomy of bones, classification of bone fractures and their treatment by osteosynthesis. Attention is also marginally paid to analysis of limb load in animals (dog, cat, horse). The following chapter of the thesis deals with the strength and stiffness analysis of the bone nail for tibia, the TR-NAIL. It is a novelty and is currently undergoing clinical testing. The main part of the dissertation thesis focuses on headless compression screws (Herbert screws). The strength and stiffness analysis is performed via a stochastic approach. A partial goal is to determine the reliability function and probability of achieving plastic deformation. An experiment is proposed to further explore headless screws. The dependence of the compression of headless screws on the geometrical parameters of the screw and its application process can be ascertained from this experiment. The experiment is followed by the FEM strength analysis of headless screw application. FEM simulations are compared to the results of the experiment and stochastic analysis. These FEM analyses were simulated for the simplified as well as real geometry of the headless screw. In both cases, geometry and material data based on real bone (5th metatars) were used, and these were extracted from CT images provided by doctors from the University Hospital in Ostrava.