Patent ID: 8617227

Claim:
A bone screw, comprising: a first screw element and a second screw element each including an external thread for threaded engagement with bone, the screw elements being connected by a pivotable joint that traps a cylindrical protuberance of the first screw element in a cylindrical cavity of the second screw element to block removal of the cylindrical protuberance from the cylindrical cavity, wherein the cylindrical protuberance and the cylindrical cavity are formed by a leading end region of one of the screw elements and a trailing end region of the other screw element, and wherein the cylindrical protuberance is movable in the cylindrical cavity to permit (a) the screw elements to be twisted relative to one another about a longitudinal axis defined by one of the screw elements and (b) the bone screw to be bent about a transverse axis of the bone screw and to an angle of at least about 5 degrees from a coaxial arrangement of the screw elements.