Spinal plate assembly, and methods of use, wherein a retaining element such as a retaining band, optionally a resiliently flexible band, mounted to a spinal plate, activates a blocking feature of the spinal plate assembly to thereby prevent the bone fastener from withdrawing out of the spinal plate assembly and past the blocking member. The apertures are typically, but not necessarily, elongate slots, elongate axes of all such slots being commonly oriented. The band can be fabricated from a variety of bio-stable, bio-compatible medical grade materials, including metals or implantable plastics. The retaining element or elements can be disposed in intermittently-located channel elements in the plate.