Patent ID: 11147592

Abstract:
A pivotal bone anchor assembly includes a receiver having a first channel configured to receive an elongate rod and an axial bore with a bottom opening, and a shank having a head portion positionable into the axial bore with the shank extending downward through the bottom opening. The assembly also includes an insert positionable into the axial bore above the head portion and having a second channel alignable with the first channel, opposite extensions extending outwardly in the direction of the channels to block rotation between the receiver and the insert, and upward-facing surfaces located radially outward from a central opening. The upward-facing surfaces are configured for releasable compressive engagement by a compressing tool after the elongate rod is received within the channels and prior to a final locking of the assembly with a closure top, so as to provisionally lock the shank from pivoting with respect to the receiver.