Vertebral fractures (VFs) represent an important clinical challenge due to their high incidence and associated physical and neurological complications. Lumbar fixations based on pedicle screws and rods are among the most widely adopted surgical treatments for VFs. Mechanical failure of spinal implants is primarily associated with non-optimal load transfer between implant and vertebrae. Sagittal spinal alignment and screw trajectory represent additional factors that contribute to implant failure. This study investigates the biomechanical differences among three lumbar fixations in two female subjects with different lordosis (L1–S1 angles: 42°, 69°, respectively), representing a neutral and a hyperlordotic lumbar profiles. Assuming an L3 fracture, the analyzed implant configurations included a long fixation (Lf) spanning L1, L2, L4, L5, and two short fixations spanning L2, L4 (Sf4) and L2, L3, L4 (Sf6).