Provided are improved pedicle screws or lateral mass screws, systems and methods for stabilizing spinal vertebrae, such as a pedicle or lateral vertebral mass, during minimally invasive spinal surgery. For example, provided is a pedicle screw or lateral mass screw having a screw shaft comprising an elongated threaded body having a vertical axis, a polyaxial screw head comprising two opposite walls that define a concave channel, and two semi-rigid, non-wire, elongated projections extending from two opposite walls of the polyaxial screw head at a positive angle in relation to a horizontal plane.