A new finite element with variable Young's modulus

The Finite Element Method (FEM) is a numerical technique that is well-established in the field of engineering. However, in biological sciences, it is just taking its first steps. Bone tissue is an example of biological material which is exposed to high loads in its natural environment. Practically every movement of the body results in changing stress levels in the bone. Nature copes with this very well but when human intervention is necessary (e.g., endoprostheses implants) bone strength has to be determined based on experience since bone tissue has a very heterogeneous structure. The goal of this paper is to demonstrate how standard FEM calculations may be readily modified to provide for variable material properties of such materials as, for example, bone or wood.