Radiolucent screw with radiopaque marker
A bone screw includes an elongate shaft extending longitudinally between a proximal end and an opposing distal end, the shaft bounding a first passageway at least partially extending between the proximal end and the distal end, the shaft being comprised of a radiolucent material. A core is disposed within the first passageway of the shaft, the core being comprised of a radiopaque material. A rounded head or a substantially U-shaped collar is either integrally formed with or is rigidly attached to the proximal end of the shaft.
1. A method of manufacturing a bone screw, the method comprising:
forming an elongated shaft about a core, the shaft having a longitudinal axis extending between a proximal end and an opposing distal end, the core extending along the longitudinal axis, the shaft being comprised of a radiolucent material and the core being comprised of a radiopaque metal, the shaft being formed by winding a flat sheet comprised of radiolucent fibers impregnated with an adhesive directly on the radiopaque core so that the adhesive binds directly to the core and so that the fibers radially encircle the core; and
forming a helical thread on an exterior surface of the shaft by removing a portion of the exterior surface of the shaft.
2. The method as recited in claim 1 , further comprising positioning a radiopaque ring layer on the helical thread.
3. The method as recited in claim 1 , further comprising attaching a head to the proximal end of the shaft.
4. The method as recited in claim 1 , wherein the shaft is comprised of an etherketone and fiber matrix.
5. The method as recited in claim 4 , wherein the etherketone comprises polyetheretherketone (PEEK).
6. The method as recited in claim 1 , wherein the step of forming the helical thread is accomplished through the use of a grinder, lathe or cutting tool.
7. The method as recited in claim 1 , wherein the fibers radially encircle the core in a helical pattern that extends along a length of the core.
8. A method of manufacturing a bone screw, the method comprising:
wrapping a flat sheet comprised of a radiolucent adhesive and radiolucent fibers directly on a core so as to form a shaft where the radiolucent fibers radially encircle the core in a helical pattern that extends along a length of the core and the radiolucent adhesive binds directly to the core, the core being comprised of a radiopaque metal;
allowing the radiolucent adhesive to set; and
forming a helical thread on an exterior surface of the shaft by removing a portion of the exterior surface of the shaft.
9. The method as recited in claim 8 , wherein the adhesive comprises an etherketone.
10. The method as recited in claim 9 , wherein the etherketone comprises polyether etherketone (PEEK).
11. The method as recited in claim 8 , wherein the step of removing a portion of the exterior surface of the shaft is accomplished through the use of a grinder, lathe or cutting tool.
12. The method as recited in claim 8 , further comprising attaching a head to the core or the shaft.
13. The method as recited in claim 8 , wherein at least a portion of the core has a non-circular transverse cross section.