Patent attributes
The invention relates to a polyaxial pedicle screw (2) comprising a screw anchor (4), which has a threaded shaft (6) and a head (8), and comprising a fork head (10), which is U-shaped in side view and has a receiving opening (16) for a corrective element, in particular a correcting rod, and two arms (12),wherein the head is polyaxially pivotably mounted in a distal end region (14) of the fork head and the fork head can be fixed in a pivoted position intended by the surgeon relative to the head, and also comprising a pressure piece (18) which can be arranged in the fork between the head and the corrective element which, on the one hand, rests on the head and, on the other hand, can be loaded by the corrective element, wherein the region of one arm of the fork head the pressure piece is supported by means of a pivot bearing (54) against this arm in the axial direction (20), and that diametrically opposite the pressure piece has a receiving region (42) for a positioning force (44) acting in the axial direction, which attempts to the pivot the pressure piece in the distal direction relative to the pivot bearing and in this way exerts the temporarily acting force in the direction of the head (8).
