| CPC A61B 17/7032 (2013.01) [A61B 17/7008 (2013.01); A61B 17/7037 (2013.01); A61B 17/7076 (2013.01)] | 19 Claims |

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1. A pivotal bone anchor assembly for securing an elongate rod to a bone of a patient with a closure top via independent provisional locking with an insert compressing tool, the pivotal bone anchor assembly comprising:
a receiver housing having a vertical centerline axis, a base portion defining a cavity communicating with a bottom of the receiver housing through a bottom opening, and an upper portion defining a channel having a transverse axis perpendicular to the vertical centerline axis and configured to receive the elongate rod, the channel communicating with the cavity and the upper portion including inner surfaces with a closure top mating structure formed therein;
a shank having longitudinal axis, a head portion with a partial spherical upper surface, and an anchor portion opposite the head portion configured for attachment to the bone, the head portion configured for positioning within the cavity of the receiver housing with the shank being pivotal with respect to the receiver housing in an unlocked configuration; and
an insert at least partially positionable into the channel of the receiver housing, the insert having a contoured seating surface configured to receive and engage the elongate rod, the contoured seating surface having a length alignable with the transverse axis of the channel of the receiver housing and a width perpendicular to the length, the length of the contoured seating surface being greater than the width such that the insert can only be positioned in the receiver housing in one predetermined orientation or the exact reverse thereof, the insert further including at least one upward-facing surface located laterally outward from the contoured seating surface,
wherein the at least one upward-facing surface of the insert is configured for releasable downward compressive engagement by the insert compressing tool after the elongate rod is received within the channel of the receiver housing and prior to a final locking of the assembly with the closure top, so as to independently provisionally lock the shank from pivoting with respect to the receiver housing.
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