Various embodiments of systems, devices, components, and methods are disclosed for mechanically coupling a bone conduction hearing aid, or a spacer or other device for a bone conduction hearing aid, to an abutment of a bone screw affixed to a patient's skull. Some embodiments of abutment attachment mechanisms employ axially-directed forces to secure a hearing aid to an abutment of a bone screw, while others employ radially directed forces to secure a hearing aid to an abutment of a bone screw.