Determination of bone density distribution in proximal femur by using the 3D orthotropic bone adaptation model

Most of the models developed and presented in the literature about bone remodelling assume bone as isotropic material. During this study, a structural model which has orthotropic bone properties is developed to simulate bone behaviour under mechanical loads. For a three-dimensional finite element modelling of proximal femoral bone, a computer code was written to investigate bone property changes owing to mechanical loads. The bone density distribution was determined after stress analysis was carried out in an iterative method. At every time step the bone properties were calculated depending on density change. Additionally, the effects of the bone remodelling parameters and sensors on numerical results were investigated. The most realistic bone density distribution in the proximal femur is obtained with strain energy density sensor. Generally initial bone density values do not have any effect on density distribution but at the low iteration numbers they may have some effects. Lastly, the density distribution of proximal femoral bone is more realistic for the dead zone size less than 0.35 and the stimulus value less than 2500.