1. The fixing device comprising a holder (2 ) and the tensioning sleeve (4, 9 ) receiving the bone screw (1), wherein the bone screw (1 ) comprises a body (10) with the front thread (11 ) and a head (12 ) at the rear end, and wherein the holder (3) comprises a through-drilled canal (30 ) and a receiving seat (32) on which is rotatably mounted tensioning sleeve (4 , 9), characterized in that the screw body (10 ) has a thickening (15) in the rear region in front of the head (12 ), the width of which increases towards the head (12), and wherein the width of the clamping sleeve (4 , 9) pain e than the width of the body of the screw (10 ) immediately before the bead (15) and smaller than the largest width of the thickening (15 ). 2. Fixing apparatus according to claim 1, characterized in that the thickening (15 ) has a maximum cone angle 15˚, preferably max 5˚, and / or a length greater than the length of the tensioning sleeve (4, 9 ), preferably at least two and a half raza.3. fixing apparatus according to claim 1 or 2, characterized in that the thickening (15 ) has a smooth envelope poverhnost.4. Fixing apparatus according to claim 1 or 2, characterized in that the preferably multiple-secondary thread (16 , 16 ") is formed on the thickening (15, 15 ) which preferably has a smaller pitch than the thread (11) to a screw body (10 ). 5. fixing apparatus according to claim 4, characterized in that the thickening (15 ) has a tapered front segment and an envelope surface, on which is formed a secondary thread (16 ). 6. fixing apparatus according to claim 4, characterized in that the pitch of the secondary thread (16 ) is from 0.4 to 0.6 from the front of the thread pitch (11 ") on the body of the screw (10 ). 7. fixing apparatus according to claim 4, characterized in that the thickening (15 ) is combined with a head (12 ) and the head (121. Устройство фиксации, включающее держатель (2′) и натяжную втулку (4′, 9′), принимающую костный винт (1′), причем костный винт (1′) включ
