Patent ID: 11419638

Abstract:
A pivotal bone anchor assembly includes a receiver having an axial bore with an internal support surface adjacent a lower opening and a channel configured to receive a fixation rod, as well as a shank having a proximal end portion configured to be pivotally supported by the internal support surface with the shank extending downward through the lower opening. The proximal end portion includes a drive socket engageable by a drive tool, an upwardly-facing planar top surface surrounding and entirely peripheral to the drive socket, and a central bore extending from the drive socket to a distal tip configured to receive a guide wire. The assembly further includes an insert with an upper surface configured to receive the fixation rod and a lower surface configured to transfer a downward force toward the proximal end portion of the shank to lock the assembly, with the planar top surface of the shank remaining spaced apart from the lower surface of the insert so as to not directly receive the downwardly-directed force when the assembly is locked by a closure.