The present research proposes a methodology to determine the strength of a spinal bone in patients who suffer from prostate cancer using diagnostic imaging, with the purpose of verifying if metastasis has occurred, and critical conditions have been reached. Advanced numerical methods allow the modelling of anisotropic materials for different applications in biomedical engineering. The computed tomography images (CAT) provide the information to create a 3D model of the bone, in this case, the lumbar vertebra L5. Using segmentation software, it is possible to identify the mechanical properties of the materials that form the bone and define anisotropic conditions. The 3D anisotropic model is evaluated using finite element analysis (FEA), considering the appropriate boundary conditions and its respective material properties, and compared with the reference case of a healthy bone in an initial stage to assess the damage. Indicators based on the changes in stiffness of the vertebra could provide evidence of the need for chirurgical intervention.