SPINE STABILIZATION SYSTEM WITH DYNAMIC SCREW

摘要

A spine stabilization system having a dynamic screw comprises at least one bone anchor assembly comprising a receiver member and a bone engaging member. In one embodiment, the bone engaging member is a screw shank extending from the receiver member. A rod is connected to the receiver member. In one embodiment, the rod comprises a ball-shaped member that engages a bearing surface provided within a cavity of the receiver member. In this embodiment, the rod is pivotably connected to the receiver member. In one such embodiment, a central axis defined by the rod pivots about a pivot point located on the central axis when the rod pivots relative to the receiver member. Accordingly, the pivot point for the rod may be provided within the cavity of the receiver member. The rod may be a fixed length or adjustable to accommodate different segmental units and patients of different sizes.