| abstract |
A bone fastener including an expandable member (10) having an axial channel (18) and an elongated element (34), insertable into the axial channel (18), is described. The expandable member (10) is configured to be insertable into a bore drilled in a bone. The distal end (14) of the expandable member (10) also may include a structure for axially releasing the expandable member (10) from an emplacement device that places the expandable member (10) into a bone opening. In one embodiment the structure for axially releasing includes a frangible membrane capable of being severed from the expandable member (10) during emplacement of the expandable member (10) in a bone opening. A rivet (22) for coupling an object to bone for use with an expandable member (10), is also described. The distal end (14) of the elongated element (34) is shaped into a radially projecting portion adapted for engagement with a washer (62) that contacts the object to be coupled. The washer (62), having upper and lower surfaces, and a bore defined between the surfaces, is disposed around a portion of the shaft. The elongated element (10) is adapted for movement independent of the washer since the radial projection of the element has a different radius of curvature than the washer (62). |