In addition, the experiments the researchers consulted used quantitative computed tomography (QCT) this is a technique for displaying an X-ray or ultrasound cross-section. Medical professionals aim two X-ray beams with varying energy levels at the bone tissue, then they subtract out the absorption level to get a reading of the bone mineral density. The material composition of a bone can be determined using a type of radiography called dual-energy X-ray absorptiometry (DXA) that works to measure bone mineral density. Trabecular bone is spongy and closer to the center, and the medullary canal is the vessel where bone marrow is stored. The cortical bone is a type of osseous tissue that is very compact and that provides support, protection for organs, levers for mobility, and the ability to exchange chemical elements. This gave them the external geometry of the bone however, in order to determine the internal composition of various tissues, they consulted previous studies on bone strength and tissue composition.ДЄ femur is made up of several sections: the trabecular bone, cortical bone, and medullary canal (shown below). The researchers began by scanning a human femur using a three-dimensional laser scanner, and then using this information, they constructed a 3D finite element model. Simulating Isotropic and Anisotropic Materials in a Femur By using both isotropic and anisotropic materials in their models, the researchers found the material composition that produced results that most closely matched data from experiments done on real human femurs. Previous femur models assumed that the human femur was composed entirely of isotropic materials however, these models failed to predict the correct fracture patterns that occur when a femur is exposed to high stress. One of the modeling techniques that they explored was the implementation of isotropic materials, materials that respond the same way to forces applied in different directions, and anisotropic materials, those that have different physical properties depending on the direction of the applied force. The results of their study were presented in the paper вЂњ Determination of Mechanic Resistance of Osseous Elements through Finite Element ModelingвЂќ at the COMSOL Conference 2013. Using COMSOL Multiphysics, the researchers experimented with different finite element models to determine the best way to design a model that most closely resembled a real bone. When researchers from the Universidad Tecnologica de Pereira, Colombia set out to determine the geometry, dimensions, and mechanical strength of a human femur, they employed the help of multiphysics simulation. Simulating bone strength starts with a simple map of the external topology of the bone and then delves into its complex internal structure and composition.ДЇEM Is a Leg Up on Modeling Bone Strength However, it is possible for researchers to get measurements of bone strength by modeling the entire makeup of the bone and using multiphysics simulation to perform stress and strain analyses. There is not currently a single-purpose device in the field to test bone strength. The question of exactly how strong living bones are poses many important considerations for the medical industry.

Isotropic and anisotropic materials