Device for installing an anchor in a bone

Abstract

A device and method for installing an anchor in a bone of a patient employs an anchor body having expandable side walls in a tapered shape with retention members on their external surfaces, and an expansion member within the anchor body which is pulled to an engaged position where it presses on the inside of the side walls to expand them outwardly to engage the retention members with the bone walls of a borehole in which the anchor body is inserted. Preferably, the anchor body is sectioned by slits to form expandable side wall sections below an expansion joint or deformation wrinkle. The side walls have containment ring sections at their distal ends for retaining the expansion member inside the anchor body. The expansion member may be formed as a conical plug with a central aperture and tab recesses on its underside for insertion of an elongated scissors-type instrument with movable prongs that engage into the tab recesses of the expansion plug. Alternatively, the expansion tool can have a threaded tip for threading in a threaded bore formed in the expansion plug. The anchor body may have guide ribs that fit in slot recesses in the expansion plug member for guiding its movement. The guide ribs may be formed as hollow tubes to allow insertion and squeezing together of the straight ends of a removal tool to dislodge the expansion member in the event removal is desired. The retention members may be formed as annular cutter blades. The anchor body may have an anchor plate at its proximal end to align and bond the anchor body with the bone surface.

Dependencies are inferred from the claim text.