In this study, a three-dimensional FE analysis was performed to investigate the effect of pedicle sc

In this study, a three-dimensional FE analysis was performed to investigate the effect of pedicle screws over varying bone conditions and loading at fused lumbar spine (L3–L4). Individual cases of flexion, extension, bending and twist had been considered to predict the effects of bone degeneracy occurred due to ageing. The stress patterns achieved during FE analysis at multiple nodal points on bone–screw interface region were analysed and compared for suitable pedicle screw selection. Results prove that the pedicle screw diameter of 6.0 mm is better among other diameters of 5.5 and 6.5mm to strengthen the rigid fixation system. Additionally, load displacement behaviour, comparison of intra discal pressures and responses of fused and intact bones with degeneracy were evaluated under different loads and body movements. The data collected during FE analysis for multiple cases of loading may be utilized to design dynamic stabilization device sand other implants.