Finite element (FE) model has found a huge interest in the human spine biomechanics through the last two decades. Many FE models of the spine have been developed and used for different purposes. FE modeling is highly used in spinal devices design in the field of spine biomechanics. Spinal devices design is challenging and need different types of tests. FE model of the spine can help the researchers to make a better decision before applying more extensive tests which are costly. This book addresses the issues related to developing accurate FE models of the cervical and the lumbar spine. Moreover, it presents some of the applications in the spinal devices design.