Various bone screws and methods for accommodating stiffness regions in bone are provided. The bone screw provided generally includes a receiver member configured to receive a fixation element and an elongate shank having different stiffness regions. In one embodiment, the elongate shank can include at least one slot for increasing the flexibility of the slotted portion of the elongate shank. In another embodiment, the elongate shank can be manufactured from materials selected to alter the stiffness of the shank. The different stiffness regions allow the bone screw to mimic the flexibility of bone, reducing the risk of fracture of the bone and/or loosening of the bone screw.
