Implant for replacing a vertebra

• US 6,616,695 B1
• Filed: 09/15/2000
• Issued: 09/09/2003
• Est. Priority Date: 01/30/1998
• Status: Expired due to Term

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Stryker Spine
• Inventors: Baccelli, Christian, Crozet, Yves
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US09/601,180
• Time in Patent Office: 1,089 Days
• Field of Search: 623/17.11, 623/17.12, 623/17.15, 623/17.16, 606/61
• US Class Current: 623/17.11
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30156 triangular
• CPC Class Codes: A61F 2002/30176 V-shaped
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/30785 parallel
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0023 triangular
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2230/0069 : cylindrical

Abstract

The invention concerns an implant (2) for replacing a vertebra at least-partially, consisting of two parts (4, 6) adapted to be mutually connected while enabling the adjustment of the implant total dimension (L), each part having an invariable dimension (m, f) homologous with the implant total dimension (L). The parts (4, 6) form a screw-nut connection with each other.

Claims

1. An implant for replacing at least part of a vertebra, the implant comprising two parts telescoping with respect to a longitudinal axis adapted to be threadably joined together and enabling a total dimension (L) of the implant to be adjusted each part having a fixed length, the two parts having respective male and female threads and forming a screw connection with each other, whereby said dimension L can be adjusted by the relative rotation of said two parts, each of the two parts respectively contacting first and second vertebral surfaces and an anti-rotation element engageable with both of said two telescoping parts to selectively prevent the relative rotation therebetween wherein said anti-rotation element is moveable in a direction transverse to said axis and a second part of said two parts has at least one slot opening therein and a first part of said two parts having a threaded opening therein and wherein said anti-rotation device is a screw threaded into said threaded opening of said first part extending into said slotted opening in said second part.

2. The implant according to claim 1, wherein at least one of the first and second parts is a unitary piece.

3. The implant according to claims 1 or 2, wherein at least one of the first and second parts has multiple pieces.

4. The implant according to claims 1 or 2, wherein the first and second cylindrical parts are tubular having walls, the walls of each part has at least one opening therethrough.

5. The implant according to claim 4, wherein at least one of the openings is elongate.

6. The implant according to claim 5, wherein the elongate opening has a longitudinal extent parallel to the longitudinal axis of the implant.

7. The implant according to claim 5, wherein one part has an elongate opening and the other part has at least one circular opening.

8. The implant according to claim 1, wherein at least one of the first ends of the first and second parts have teeth.

9. The implant according to claim 1, wherein said first and second parts have a cavity and openings connecting the cavity to the outside of the parts.

23. The implant has set forth in claim 1, wherein said anti-rotation element is moveable in a direction transverse to said axis and a second part of said two parts has at least one opening therein and a first part of said two parts having a threaded opening therein and wherein said anti-rotation device is a screw threaded into said threaded opening of said first part and extending into said opening in said second part.

10. A spinal implant comprising:

a first generally tubular part having a threaded inner surface and an end surface for contacting a first vertebra;

a second generally tubular part having a threaded outer surface, said second part outer surface threaded into said threaded inner surface of said first part for relative movement between the parts along a longitudinal axis, said second part having an end surface for contacting a second vertebra; and

an anti-rotation device connected to one of said first or second parts for selectively engaging the other of said first or second parts for selectively allowing or preventing relative rotation of said threaded surfaces said anti-rotation device moveable in a direction transverse to said longitudinal axis for said selective engagement wherein said second piece has at least one slotted opening therein and said first piece having a threaded opening therein and said anti-rotation device is a screw threaded into said threaded opening of said first piece and extending into said slotted opening in said second piece.

11. The implant as set forth in claim 10, wherein at least one of the first and second parts is an assembly of at least two parts.

12. The implant as set forth in claim 10, wherein each part has at least one opening formed in a wall of the part which opening can be superimposed to receive the anti-rotation device.

13. The implant as set forth in claim 12, wherein at least one of the openings is elongate.

14. The implant as set forth in claim 13, wherein the elongate opening extends parallel to said longitudinal axis.

15. The implant according to claim 13, wherein one part has an elongate opening and the other part has at least one circular opening.

16. The implant according to claim 10, wherein at least one of the parts has teeth formed on said end surface for contacting a vertebra.

17. An implant according to claim 10, wherein first and second parts have an inner cavity defined by walls and openings in the walls connecting the cavity to the outside of the implant.

18. The implant as set forth in claim 10, wherein said anti-rotation device is a set screw mounted on one of said parts and engageable with the other of said parts.

20. The method as set forth in claim 18, wherein the anti-rotation device connected to one of said parts is a set screw engaging an opening in the other of said parts.

21. The implant as set forth in claim 10, wherein said second piece has at least one opening therein and said first piece having a threaded opening therein and said anti-rotation device is a screw threaded into said threaded opening of said first piece and extending into said opening in said second piece.

19. A method for replacing at least part of a vertebra in a human spine, comprising:

forming an opening in the spine by removing at least part of a vertebra, said removing of said vertebra leaving facing bone surfaces;

inserting a two piece telescoping implant having an end on a first piece and an end on a second piece for engaging said vertebral facing bone surfaces into said opening, said implant first piece having a female part with a threaded inner surface and said second piece having a male part with a threaded outer surface threadably engaging the inner thread of the female part for relative movement along a longitudinal axis;

adjusting the length of the implant to match a height of said opening between the facing bone surfaces along said longitudinal axis by rotating the first piece female part with respect to the second piece male part; and

locking said implant at the adjusted length by activating an anti-rotation device connected to one of said male or female parts for selectively engaging the other of said male or female parts to prevent rotation therebetween said locking element moveable in a direction transverse to said longitudinal axis for said selective engagement wherein said second piece has at least one slotted opening therein and said first piece having a threaded opening therein and said anti-rotation device is a screw threaded into said threaded opening of said first piece and extending into said slotted opening in said second piece.

22. The implant as set forth in claim 19, wherein said second piece has at least one opening therein and said first piece having a threaded opening therein and said anti-rotation device is a screw threaded into said threaded opening of said first piece and extending into said opening in said second piece.