Rotationally ratcheting bone screw

摘要

A rotationally ratcheting bone screw including a body having a distal end formed with an engagement tip for engaging bone tissue, and a shaft formed with a unidirectional stop. The bone screw further includes a fastening element formed with an opening complementally configured to receive the shaft and responsive to relative rotation between the shaft and fastening element to axially advance along the shaft. The fastening element includes a rotationally sensitive ratchet element to cooperate with the stop and inhibit relative counter-rotation between the shaft and the fastening element.