Locking and lagging bone screws

Patent metadata

Field	Value
Publication number	US-9539040-B2
Application number	US-201514716280-A
Country	US
Kind code	B2
Filing date	May 19, 2015
Priority date	Nov 16, 2012
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A locking and lagging bone screw. The screw includes a head having an outer surface which is at least partially threaded and a shaft which is at least partially threaded having a first end coupled to the head and a second end adapted to be fastened to bone. The head of the screw is able to rotate independently of the shaft. Thus, the head of the screw can be locked to a bone plate by using a first driver (e.g., a torx driver) and the plate can be lagged to the bone by using a second driver (e.g., a hex driver).

First claim

What is claimed is:

1. A locking and lagging bone screw comprising:
a shaft elongate along a central axis, the shaft including a first shaft end and a second shaft end opposite the first shaft end along the central axis;
a head including a first head end and a second head end opposite the first head end, the head configured to be coupled to the shaft such that: 1) the head is rotatable about the central axis independently of the shaft, 2) the first shaft end faces the second head end, and 3) the first shaft end is spaced from the second head end along the central axis by a gap; and
a connection screw configured to bridge the gap and couple the head to the shaft;
wherein, when the head and the shaft are in a fully assembled configuration, 1) the connection screw is rotatable relative to the head about the central axis, and 2) the connection screw is the only portion of the locking and lagging screw that bridges the gap.

2. The locking and lagging bone screw of claim 1 , wherein the head defines a first cavity, and the connection screw defines a second cavity that is at least one of a different size and a different shape from the first cavity.

3. The locking and lagging bone screw of claim 2 , wherein the connection screw includes a connection screw head that defines the second cavity, the connection screw includes a connection screw shaft that includes a threaded outer surface, and the shaft includes a threaded inner surface that defines a hole configured to receive the connection screw shaft.

4. The locking and lagging bone screw of claim 3 , wherein the connection screw head is inserted in the first cavity and the connection screw shaft is inserted in the hole.

5. The locking and lagging bone screw of claim 1 , wherein the head is rotatable along a variable angle relative to the shaft.

6. The locking and lagging bone screw of claim 1 , wherein the shaft includes a threaded outer surface.

7. The locking and lagging bone screw of claim 6 , wherein the head includes a threaded outer surface having a pitch that is different than a pitch of the threaded outer surface of the shaft.

8. The locking and lagging bone screw of claim 1 , wherein the head includes a threaded outer surface.

9. The locking and lagging bone screw of claim 1 , wherein, in the fully assembled configuration, the connection screw is rotatably coupled to the shaft so that rotation of the connection screw causes the shaft to rotate about the central axis.

10. A locking and lagging bone screw comprising:
a shaft elongate along a central axis, the shaft including a first shaft end and a second shaft end, the first shaft end opposite the second shaft end in a first direction along the central axis;
a head including a first head end and a second head end opposite the first head end, the head configured to be coupled to the shaft such that: 1) the head is rotatable independently of the shaft about the central axis when the shaft and the head are in a fully assembled configuration, 2) the first shaft end faces the second head end, and 3) the second head end is positioned closer to the first head end with respect to the first direction than any point on the shaft is positioned from the first head end with respect to the first direction.

11. The locking and lagging bone screw of claim 10 , further comprising a connection screw coupled to both the shaft and the head such that: 1) a first end of the connection screw is opposite a second end of the connection screw in the first direction and 2) the second end of the connection screw is positioned closer to the second shaft end with respect to the first direction than any point on the head is positioned from the second shaft end with respect to the first direction.

12. The locking and lagging bone screw of claim 10 , further comprising a connection screw including a connection screw head and a connection screw shaft, wherein the head defines a cavity configured to receive the connection screw head, and the shaft includes a threaded inner surface that defines a hole configured to receive the connection screw shaft.

13. The locking and lagging bone screw of claim 12 , wherein the connection screw head is inserted in the cavity, and the connection screw shaft is inserted in the hole.

14. The locking and lagging bone screw of claim 13 , wherein rotation of the connection screw translates the shaft relative to the head in the first direction.

15. The locking and lagging bone screw of claim 10 , wherein the head is rotatable along a variable angle relative to the shaft.

16. The locking and lagging bone screw of claim 10 , wherein the shaft includes a threaded outer surface.

17. The locking and lagging bone screw of claim 16 , wherein the head includes a threaded outer surface having a pitch that is different than a pitch of the threaded outer surface of the shaft.

18. A kit comprising:
a locking and lagging bone screw including a head, and further including a shaft that is elongate along a longitudinal axis and rotatable relative to the head about the longitudinal axis when the head and the shaft are in a fully assembled configuration;
a plate including a first surface, a second surface opposite the first surface, and an inner surface that defines a hole that extends from the first surface to the second surface,
wherein the plate is configured such that the locking and lagging bone screw is insertable into the hole at a plurality of angles.

19. The kit of claim 18 , wherein the head includes an outer surface that is at least partially threaded, the inner surface of the plate is at least partially grooved, and the outer surface is configured to engage with the inner surface to lock the locking and lagging screw at one of the plurality of angles.

20. The kit of claim 18 , wherein the inner surface defines a conical shape of the hole.

21. The kit of claim 18 , wherein the hole extends from the first surface to the second surface along a central hole axis, and the plurality of angles are measured between the central hole axis and the longitudinal axis.

Assignees

• Depuy Synthes Products Inc

Inventors

• Vennard Daniel
• Miller William

Classifications

• A61B17/8605

  Heads, i.e. proximal ends projecting from bone · CPC title

• A61B17/8685 Primary

  comprising multiple separate parts · CPC title

• A61B17/8615

  at the central region of the screw head · CPC title

• A61B17/8057

  the interlocking form comprising a thread · CPC title

• A61B17/844

  with expandable anchors or anchors having movable parts · CPC title