BONE ANCHORS AND METHODS OF FORMING THE SAME

摘要

A bone anchor (.10} including a bone engaging element (.12) and an implant engaging element (14). The bone engaging element (32) includes a first portion (.16) formed of a first material and a second portion (18) formed of a second material and extending at least partially along a length of the first portion (16), and with the second portion (1 S) of the bone engaging element ( 12) positioned between the first portion (16) and adjacent bone tissue when the bone engaging element (12) is engaged with the bone to provide an interface with the adjacent bone tissue. In one embodiment; the first portion (16) of the bone engaging element (12) exhibits a first level of rigidity and the second portion (18) exhibits a second level of rigidity less than the .first level of rigidily. In another embodiment, the bone engaging element (12) includes external threads (20), with the second portion (18) of the bone engaging element (12) defining at least a portion of the external threads (20).