Patent ID: 8926669
Filing Date: 2015-01-06
Classification: A61B

Abstract:
1. A polyaxial pedicle screw assembly comprising: a polyaxial pedicle screw having a shaft and head; a rod holding element that defines a screw hole opening, a curved bearing surface, a chamber, a saddle area, a cutaway area, a head seating surface, and a threading area; a polyaxial insert disposed within the chamber, wherein the polyaxial insert defines a curved lower insert bearing surface, a screw head bearing surface defined in and extending upwardly from the curved lower insert bearing surface, and an upper surface, wherein the curved lower insert bearing surface has a curvature that is substantially the same as the curvature of the rod holding element curved bearing surface; wherein the polyaxial insert is positioned within the chamber of the rod holding element such that the curved lower insert bearing surface of the polyaxial insert contacts the rod holding element curved bearing surface, and wherein the curved contact between the polyaxial insert and the rod holding element allows for pivoting motion of the polyaxial insert within the rod holding element; wherein the polyaxial pedicle screw is disposed so that a threaded portion of the shaft passes through the screw hole opening, and the polyaxial pedicle screw head contacts the screw head bearing surface of the polyaxial insert; a rod disposed to rest on the upper surface of the polyaxial insert; and a set screw joined to the threading area of the rod holding element so as to secure the rod to the upper surface of the insert and to lock the polyaxial pedicle screw and rod holding element into a desired position.