A fixation apparatus comprises a holder and a tension sleeve receiving a bone screw, wherein the bone screw has a shaft with a front thread and a head at the rear end, and the holder has a through borehole with a receiving seat, in which the tension sleeve is mounted and able to swivel, while the shaft has a thickening in a rear region, to the front of the head, whose width increases toward the head, and the width of the tension sleeve is larger than the width of the shaft immediately before the thickening and smaller than the greatest width of the thickening. When screwed in, the thickening widens the tension sleeve so that it is pressed by its envelope against the wall of the receiving seat. In this way, an angle-stable pressing is achieved for any given orientation of the bone screw.
