Bone screw

• US 20060106383A1
• Filed: 12/29/2005
• Published: 05/18/2006
• Est. Priority Date: 11/10/2000
• Status: Abandoned Application

• Current Assignee: Biedermann Technologies GmbH & Co. KG
• Original Assignee: Biedermann Motech GmbH
• Inventors: Biedermann, Lutz, Harms, Jurgen
• Application Number:
  US11/319,427
• Publication Number:
  US 20060106383A1
• Time in Patent Office: Days
• US Class Current: 606/301
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7038 to a different extent in different directions, e.g. within one plane only
• CPC Class Codes: A61B 17/7067 Devices bearing against one or more spinous processes and also attached to another part of the spine; Tools therefor
• CPC Class Codes: A61B 17/8605 Heads, i.e. proximal ends projecting from bone

Abstract

A bone screw having a screw member possessing a threaded section and a head and a receiving part at the head end for receiving a rod to be connected to the bone screw is provided. The receiving part has on open first bore and a substantially U-shaped cross-section having two free legs provided with a thread. Furthermore, the receiving part has a second bore on the end opposite to the first bore whose diameter is greater than that of the threaded section and smaller than that of the head. On the bottom of the first bore a seat for the head is provided. In order that the screw member can be pivoted to at least one side by an enlarged angle, the edge bounding the free end of the second bore viewed relative to the axis of the first bore is of asymmetric construction.

Claims

1. A bone fixation assembly comprising:

a coupling element having an inner surface defining a first bore coaxial with a first longitudinal axis and a second bore coaxial with a second longitudinal axis, wherein said first and second longitudinal axes intersect and are in communication with one another; and

an anchoring element assembled with said coupling element, said anchoring element having a first end for insertion into bone.

2. The assembly of claim 1, wherein said coupling element has an upper end and a lower end, said first bore extending from said upper end toward said lower end and said second bore extending from said lower end toward said upper end.

3. The assembly of claim 2, wherein said first and second bores are in communication with one another between said upper and lower ends of said coupling element.

4. The assembly of claim 2, wherein said upper end of said coupling element defines a first plane and said lower end of said coupling element defines a second plane, and wherein said first and second planes intersect one another.

5. The assembly of claim 2, wherein said anchoring element projects from said lower end of said coupling element.

6. The assembly of claim 1, wherein said anchoring element is a separate member assembled with said coupling element so that said coupling element and said anchoring element are movable relative to one another.

7. The assembly of claim 2, wherein said second bore includes a seat adjacent said lower end of said coupling element, and wherein said seat is adapted to engage said anchoring element.

8. The assembly of claim 7, wherein said anchoring element has a head having a substantially spherical underside adapted to engage said seat.

9. The assembly of claim 8, wherein said seat has a substantially concave surface adapted to engage the spherical underside of said head.

10. The assembly of claim 8, further comprising a locking element engageable with said coupling element for locking the position of said coupling element with respect to said anchoring element.

11. The assembly of claim 10, wherein said locking element urges a stabilizing rod toward said lower end of said coupling element which in turn forces said head of said anchoring element against said seat for locking said coupling element and said anchoring element from further movement relative to one another.

12. The assembly of claim 11, wherein said seat is defined by an interior wall of said coupling element.

13. The assembly of claim 1, wherein said coupling element has an exterior surface, an upper end and a lower end, said rod-receiving openings extending from said upper end toward said lower end, and wherein said coupling element comprises etes cuts between said exterior surface and said rod-receiving openings for minimizing the width of said coupling element.

14. The assembly of claim 1, wherein said anchoring element is a screw fastener having screw threads extending from said first end toward a second end thereof.

15. The assembly of claim 3, wherein said anchoring element has a head with a substantially spherical shape and said coupling element has a seat adjacent said lower end thereof, and wherein said spherical head is adapted to engage said seat.