POROUS BONE SCREW

摘要

A bone screw is described which includes a one-piece threaded screw body composed at least partially of a rigid foam. The screw body is headless and includes a bore extending therethrough to define a cannula and thereby providing the screw body with an annular shape defining a radial wall thickness. At least a central portion of the screw body is formed of the rigid foam which defines a matrix having a plurality of inter-connected pores therein. The inter-connected pores are disposed throughout the complete radial wall thickness of the screw body from an outer surface of the screw body to an inner surface thereof within the cannula, such as to permit bone in-growth through the complete radial wall thickness of the annular screw body. The inter-connected pores and the cannula thereby respectively allow bone in-growth through the complete radial wall thickness and the full axial length of the screw body.