Patent ID: 8551094

Claim:
A spinal fusion device, comprising: an elongate body, having a proximal end and a distal end; a helical anchor on the distal end; a first retention structure on the body, proximal to the anchor; and an axial lumen extending from the proximal end to the distal end of the elongate body to accommodate placement of the elongate body over a placement wire; a proximal anchor, moveably carried by the body, the proximal anchor comprising a tubular sleeve having a radially outwardly extending transverse flange, the transverse flange having a curved surface; a second retention structure on the interior of the tubular sleeve for cooperating with the first retention structure on the body; and a washer, moveably carried by the flange of the proximal anchor, the washer comprising an aperture, an indented surface generally corresponding to the curved surface of the flange, and a base surface, the aperture being configured with the proximal anchor being moveably received therethrough with the curved surface of the flange contacting the indented surface of the washer for distributing a load exerted by the proximal anchor across the base surface of the washer, the base surface of the washer being adjustable relative to a longitudinal axis of the proximal anchor for maximizing bone contact with the base surface; wherein the proximal anchor and the transverse flange thereof are movable in the distal direction with respect to the body without rotation, and wherein both the first retention structure and second retention structure resist proximal movement of the proximal anchor with respect to the body; and wherein the washer remains adjustable relative to the longitudinal axis of the proximal anchor as the entirety of the proximal anchor is moved in the distal direction with respect to the body.