Multi-layer composite material bone screw
First Claim
1. A fiber-reinforced composite material bone screw comprising:
- a screw core comprising fiber-reinforced polymer matrix composite material having a first fiber arrangement; and
a thread region circumferentially surrounding the screw core at least along a threaded shaft of the screw, the thread region comprising fiber-reinforced polymer matrix composite material having a second fiber arrangement;
wherein the fibers of the fiber-reinforced polymer matrix composite material of the thread region comprise at least a first fiber population and a second fiber population, wherein at least 10% of the fibers of said first population pass at an angle of at least 10 degrees relative to fibers of said second fiber population;
said at least first and second populations interspersed with each other and within said polymer matrix of the thread region; and
wherein the thread region is formed by compression molding.
2 Assignments
0 Petitions
Accused Products
Abstract
Composite material screws and construction techniques are described comprising reinforcing fibers directed in different winding directions and/or angles at different layers (radial depths) of the screw. Optionally, the screw comprises composite material layers wound with fibers at both the pitch of the thread of the screw and at a steeper pitch (for example, about 45°). Optionally, an outer layer of the screw comprises a relative radiolucent construction and/or material, with a more radiopaque construction and/or material positioned underneath the outer layer such that at least a portion of the screw outline is delineated by a radioimaging technique (for example, fluoroscopy, CT, or MRI), while maintaining a sufficiently artifact-free image around the screw that the image characteristics of the surrounding tissue are still determinable.
165 Citations
27 Claims
-
1. A fiber-reinforced composite material bone screw comprising:
-
a screw core comprising fiber-reinforced polymer matrix composite material having a first fiber arrangement; and a thread region circumferentially surrounding the screw core at least along a threaded shaft of the screw, the thread region comprising fiber-reinforced polymer matrix composite material having a second fiber arrangement; wherein the fibers of the fiber-reinforced polymer matrix composite material of the thread region comprise at least a first fiber population and a second fiber population, wherein at least 10% of the fibers of said first population pass at an angle of at least 10 degrees relative to fibers of said second fiber population;
said at least first and second populations interspersed with each other and within said polymer matrix of the thread region; andwherein the thread region is formed by compression molding. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
Specification