Abstract: An anterior cervical plate assembly is characterized in that it comprises a base plate and fastener with a two-part locking mechanism. The locking mechanism includes a blocking plate that translates along a recess in the base plate to partially overlap a fastener, preventing back-out. The locking mechanism also includes a locking piece that extends through the base plate and has a rotational cam surface that causes the translation of the blocking plate.

Abstract: A uniplanar pedicle fastener that is bottom-loaded and has a two-part pivoting mechanism is provided. The bottom loading is effected by particular complementary shapes of the fastener head and an opening in the bottom of the housing. The pivoting mechanism is provided by a protrusion and recess in the fastener head and housing bottom, respectively. The complementary dimensions of the fastener head, protrusion, housing opening, and recess permit both the bottom loading at one orientation, and, at a second generally perpendicular orientation, the pivoting articulation. The uniplanar pedicle fastener of the present invention can be attached to other pedicle fastener assemblies as part of a spinal stabilization apparatus.