Abstract: Polymeric medical fixation screws with multiple cannulations and thereby a reduced risk of shearing while being torqued into place are provided. The polymeric screws have at least two cannulae, on either side of a central longitudinal axis of the screw, extending parallel to the longitudinal axis. Torquing instruments are inserted into the cannulae so that the applied torque force for driving the screws into a bone hole is distributed along the shaft of the screw. In one embodiment, the invention provides interference screws, while in other embodiments the invention provides medical fixation screws with heads and soft tissue-to-bone anchors or suture anchors. The polymeric screws may be fabricated from virtually any suitable biocompatible polymers or composites, including bioabsorbable polymers and their composites.

Abstract: Coated Prosthetic devices useful in the medical and dental fields, such as dental implants, intramedullary nails, and total hip prostheses, are provided having a porosity or density gradient in the sintered plastic coating. The higher porosity is at the outer surface which facilitates bone ingrowth while the lesser porosity which has a higher density and a more continuous plastic layer is on the inner surface and thus provides better adhesion to the load bearing component.