14. The improvement of claim 13 wherein the aperture in the receiver first surface is a pair of opposed apertures and the retainer tab is a pair of opposed resilient tabs, each one of the tabs being received in one of the apertures.
13. In a polyaxial bone anchor, the improvement comprising: a) a receiver defining a chamber communicating with a channel, the channel sized and shaped for receiving a portion of a longitudinal connecting member, the chamber having an inner surface further comprising an aperture defined by a first surface formed therein and a second seating surface located near a bottom opening of the receiver, the chamber communicating with the bottom opening; b) a shank having a body and a curved upper portion, the shank body extending through the receiver bottom opening; and c) a resilient open retainer located in the chamber, the retainer having a base and an upper structure having a resilient outwardly extending tab having a top surface that is located on the top of the retainer, the retainer having two positions, a shank loading position and a shank restraining position, while in the shank loading position, the base being expandable in the chamber about the shank upper portion and receiving the shank upper portion therethrough to capture the shank upper portion in the chamber, the tab engaging the first surface of the aperture, and in the shank restraining position, the shank and retainer in combination are lowered in the chamber such that the retainer base is seated on the receiver second seating surface, and the tab expands outwardly through the aperture with the retainer being restrained by the first surface with respect to upward, downward, and rotational movement with respect to the receiver by the tab, the shank being able to be manipulated in a polyaxial direction with respect to the receiver when the retainer is in either the shank loading or shank restraining positions.