Spinal intervertebral implant adjustable in situ comprising hard pass point

• US 7,156,874 B2
• Filed: 12/05/2001
• Issued: 01/02/2007
• Est. Priority Date: 12/05/2000
• Status: Expired due to Term

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Stryker Spine
• Inventors: Paponneau, Francois, Conchy, Free
• Primary Examiner(s): Robert; Eduardo C.
• Assistant Examiner(s): Comstock; David
• Application Number:
  US10/433,769
• Publication Number:
  US 20050209697A1
• Time in Patent Office: 1,854 Days
• Field of Search: 623/17.11, 623/17.16, 623/17.12
• US Class Current: 623/17.11
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• 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 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30289 helically-coiled
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30354 Cylindrically-shaped protrusion and recess, e.g. cylinder of circular basis
• CPC Class Codes: A61F 2002/30364 Rotation about the common longitudinal axis
• CPC Class Codes: A61F 2002/30365 with additional means for limiting said rotation
• CPC Class Codes: A61F 2002/3037 Translation along the common longitudinal axis, e.g. piston
• CPC Class Codes: A61F 2002/30372 with additional means for limiting said translation
• 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 2002/30601 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 2002/3079 : Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section

Abstract

The invention concerns a spinal intervertebral implant (200) comprising at least an upper element (203), a lower element (205), and an intermediate member (201) adapted to co-operate with the upper and lower elements by helical linking means (207, 254) including means (216) forming hard pass points when the helical linkage is carried out.

Claims

1. A spinal intervertebral implant comprising at least an upper element, a lower element, and an intermediate member which can cooperate with the upper and lower elements via helical linking means, wherein the helical linking means include cam and a cam follower which is able to come into contact with a bearing surface of the cam for forming hard pass points when the helical linkage is carried out, the intermediate member including the cam or cam follower.

2. The implant as claimed in claim 1, wherein the bearing surface has zones forming the hard pass points.

3. The implant as claimed in claim 2, wherein the zones forming the hard pass points comprise pass points protruding from the bearing surface.

4. The implant as claimed in claim 3, wherein the hard pass points are bosses.

5. The implant as claimed in claim 1, wherein the intermediate member can be received in one of the upper and lower elements.

6. The implant as claimed in claim 5, wherein the intermediate element can be received in the other of the upper and lower elements.

7. The implant as claimed in claim 1, wherein one of the upper and lower elements can be received in the intermediate member.

8. The implant as claimed in claim 7, characterized in that the other of the upper and lower elements can be received in the intermediate member.

9. The implant as claimed in claim 1, wherein the helical linkage between the intermediate member and the upper element has a direction of screwing counter to that of the helical linkage between the central element and the lower element.

10. The implant as claimed in claim 1, further comprising means for blocking in position at least one of the upper and lower elements relative to the intermediate member.

11. The implant as claimed in claim 10, wherein the means for blocking in position comprise a stud.

12. The implant as claimed in claim 11, wherein the stud comprises a part which is eccentric in relation to the main axis of use of the stud.

13. The implant as claimed in claim 11, wherein the stud comprises a part which can be screwed.

14. The implant as claimed in claim 1, further comprising means for anchoring the implant in the vertebral plateaus.

15. The implant as claimed in claim 1, wherein the upper and lower elements can fit into one another through being of complementary shape.

16. The implant as claimed in claim 15, wherein the upper and lower elements fit into one another with sliding.

17. The implant as claimed in claim 15 or 16, wherein each lower and upper element has a general U-shape, the elements being able to fit into one another with the U-shapes in opposition.

18. The implant as claimed in claim 15 or 17, wherein with at least one of the upper and lower elements comprising the cam, said cam has an opening facing its bearing surface.

19. A spinal intervertebral implant comprising:

an upper element having a first slot which extends at an angle with respect to the longitudinal axis of said implant, said first slot having a plurality of first ramps along a length thereof;

a lower element having a second slot which extends at an angle with respect to the longitudinal axis of said implant, said second slot having a plurality of second ramps along a length thereof; and

an intermediate member having at least two studs disposed within the first and second slots of the upper and lower elements, whereby said studs are adapted to cooperate with said first and second ramps.

20. The implant of claim 19, wherein upon rotation of said upper and lower elements with respect to said intermediate member, the engagement between said studs and said ramps form hard pass points corresponding to different heights of said implant.

21. The implant of claim 20, further including set screws for locking said upper and lower elements with said intermediate member upon achievement of a desired implant height.

22. The implant of claim 21, wherein said upper and lower elements each include two slots having a plurality of ramps along their lengths, and said intermediate member includes four studs for cooperation with each said slot.

23. The implant of claim 20, wherein opposite rotation of said upper and lower elements with said intermediate member varies the height of said implant.

24. A spinal intervertebral implant comprising at least an upper element, a lower element, an intermediate member which can cooperate with the upper and lower elements via helical linking means and means for anchoring the implant in vertebral bodies, wherein the helical linking means include means for forming hard pass points when the helical linkage is carried out.