Porous intervertebral spacer

Abstract

An intervertebral spacer suitable for use as a spinal implant includes a rigid, porous body made of a biocompatible material. The body is strong enough to accommodate loads imposed by adjacent vertebrae and is porous enough to facilitate tissue ingrowth and bony fusion. The porosity is provided by a plurality of randomly sized, substantially interconnected voids disposed throughout the body. The spacer can be manufactured by a variety of techniques. In one technique, a plurality of polymer pellets are placed in a mold of a desired shape and heated to melting or near-melting temperature. The pellets are fused together to form a porous, rigid structure. In another technique, tortuous strands of a biologically inert material are intermixed with each other and are sintered into a desired shape in a mold. The spacer also can be made of a sintered mixture of strands and pellets of a biologically inert material. The material for the strands and the pellets typically is titanium or a titanium alloy, although other metals and certain polymers such as PEEK can be used. In another techniques, the spacer is made of void-containing foam metal, void-containing powdered metal, or void-containing ceramic. The spacer also can be made from a solid block of a biocompatible material by drilling or machining a plurality of interconnected openings that extend through the block. The spacer can be provided in a variety of shapes to suit the needs of individual patients.

Dependencies are inferred from the claim text.