Mounting screws for vertebrae atlas and axis

consisting fixing screw a self-tapping screw (1) which has a flat end with two grooves and a threaded portion, the screw (1) for attachment to be inserted into an intervertebral portion (55) of an atlas ( 5) and an axis (6) so that the screw (1) securing blocks atlas surfaces (5) and the axis (6) thereby fixing the atlas (5) and the axis (6). the screw of the dimensions (1) securing are such that the screw (1) for fixing blocks safely atlas (5) and the axis (6) and the screw (1) for fixing does not exceed part intervertebral (55).