Patent ID: 8083776
Filing Date: 2011-12-27
Classification: A61B

Abstract:
1. Vertebral fixation device comprised of the following: a pedicle screw, which constitutes a head with a partially spherical configuration, intended for introduction in a vertebra; a rosette with an upper promontory from which flexible slats come down, intended to press on the head, fixing the pedicle screw and placing the device at a desired angle; a tulip with two lateral notches, a threaded inner sector, and partially spherical lower cavity, ending in a lower conical wall, in which the rosette is housed; a bar, which constitutes a link with other devices, housed in the lateral notches; a locking cap with circular openings to allow the bar to pass through, which moves axially on an outer face of the tulip, and a closing screw associated to the locking cap which is threaded on the threaded sector inside the tulip and fixes the bar against the rosette; wherein the tulip and the locking cap comprise opposite-facing flat indentations on an outer face of the tulip and the locking cap, respectively; wherein the rosette is configured to receive pressure directly from the bar in the absence of a complementary tightening screw to fix the rosette to the head of the pedicle screw; and wherein the rosette has a conical indentation on an upper face of the upper promontory, which is prolonged towards an inside from a perimeter edge, the flexible slats of the rosette incorporate a conical section that adapts to the lower conical wall of the tulip, to strangle the head of the pedicle screw when the bar exerts pressure on the rosette when both are pushed by the closing screw; and wherein the rosette has a wide opening that is prolonged in a center of the rosette after the conical indentation in which a bushing is housed with a possibility of axial movement by the pressure that the bar exerts on the rosette, which in turn exerts pressure on the head of the pedicle screw collaborating to strangle the head and thus fixing the position of the pedicle screw.