Patent ID: 7524326
Filing Date: 2009-04-28
Classification: A61B

Abstract:
1. A bone screw for attaching a spinal fixing element comprising: a screw shank that can be fixed in place in a bone, the screw shank having a thread for screwing into the bone; a screw head; and a fastening device including a fastener, a retaining area for mounting the spinal fixing element, and a fastening area for mounting the fastening device on the screw head; the screw head including a fastening area for receiving the fastening device, the fastening area including a threaded section for fixing the fastening device in place; the screw head fastening area including a recess having an opening, a stepped inner wall, a wide portion, a narrow portion, and a longitudinal axis, the wide portion being threadless and adjacent the opening, and the narrow portion being threaded and distant from the opening; the fastening area of the fastening device including an extension for engaging the inner wall of the wide portion of the recess of the screw head, the extension being fixable in place in non-rotating fashion in the recess by means of the fastener engaging the narrow portion of the recess, and when not fixed in place, the extension being rotatable about the longitudinal axis of the recess relative to the screw head, at least over part of a circumference of the recess; the fastening device further including a first leg facing the screw head and a second leg facing away from the screw head, between which the spinal fixing element can be fixed in place; the extension being provided with a centered through hole extending in its longitudinal direction for receiving the fastener; the extension being arranged at the first leg facing the screw head and protruding towards the screw head; wherein d wherein the fastener fastens the fastening device to the screw head fastening area and simultaneously is adapted to fasten the spinal fixing element in place on the bone screw.