Intervertebral implant

• US 20070191959A1
• Filed: 02/08/2007
• Published: 08/16/2007
• Est. Priority Date: 08/13/2004
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Studer, Armin, Hartmann, Stephan
• Granted Patent: US 7,771,456 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• CPC Class Codes: A61B 17/7062 Devices acting on, attached to, or simulating the effect of, vertebral processes, vertebral facets or ribs rib fixation devices A61B17/8076; Tools for such devices

Abstract

An intervertebral implant has two U-shaped inserts set over each other with a center piece in between. The two inserts each have an opposing base surface, two lateral side surfaces, and a contact surface. The contact surface has a channel configured to receive a spinal process of a vertebral body. The center piece has two resting surfaces corresponding respectively to each contact surfaces. The contact and resting surfaces each have corresponding structures that can engage each other such that the U-shaped inserts can each be fastened in a detachable manner to the center piece. The U-shaped inserts each have on the same lateral side surface connecting means to fasten the inserts to gripping elements of a surgical instrument. And the first and second structures can be engaged or disengaged only by the lateral side surface fitted with the connecting means.

Claims

1. An intervertebral implant comprising:

a central axis;

two U-shaped inserts set over each other with respect to the central axis, each insert having opposing base surfaces, first and second lateral side surfaces, a ventral side surface, a dorsal side surface, and a contact surface, the contact surface having a channel configured to receive a spinal processes of a vertebral body; and

a center piece operative to be inserted across the central axis between the base surfaces, the center piece having first and second resting surfaces corresponding respectively to the two base surfaces of the U-shaped inserts, each of the resting surfaces having a first structure thereon;

wherein;

each of the base surfaces has a second structure thereon configured to engage a respective first structure such that, after the first and second respective structures engage, the U-shaped inserts are fastened in a detachable manner to the center piece parallel to the central axis;

the U-shaped inserts each have on the same lateral side surface connecting means operative to fasten the U-shaped inserts to gripping elements of a surgical instrument; and

the first and second structures are operative to be engaged or disengaged only via the lateral side surface having the connecting means.

2. The intervertebral implant of claim 1 wherein the first and second structures are configured in a form-locking manner parallel to a transversal axis set across the central axis and crossing the ventral and dorsal side surfaces.

3. The intervertebral implant of claim 1 wherein the first and second structures are configured in a form-locking manner parallel to the central axis.

4. The intervertebral implant of claim 1 further comprising locking means by which the first and second structures are operative to be held engaged across the central axis.

5. The intervertebral implant of claim 4 wherein the locking means is detachable.

6. The intervertebral implant of claim 1 wherein the first structure comprises a male dovetail guide and the second structure comprises a corresponding female dovetail guide having a longitudinal axis running across the central axis.

7. The intervertebral implant of claim 6 wherein the male and female dovetail guides have longitudinal axes running across a transversal axis set across the central axis and crossing the ventral and dorsal side surfaces.

8. The intervertebral implant of claim 6 wherein the locking means comprises a screw operative to be screwed into the U-shaped inserts, and the male dovetail guide is prevented from shifting in the female dovetail guide by the screw.

9. The intervertebral implant of claim 6 wherein the female dovetail guide is closed toward the lateral side surface that does not have the connecting means.

10. The intervertebral implant of claim 6 wherein the male and the female dovetail guides are tapered toward the lateral side surfaces that do not have the connecting means.

11. The intervertebral implant of claim 6 wherein the longitudinal axis of the male and female dovetail guides is curved.

12. The intervertebral implant of claim 6 wherein the longitudinal axis of the male and female dovetail guides is straight.

13. The intervertebral implant of claim 1 wherein the implant is elastically deformable.

14. The intervertebral implant of claim 13 wherein the implant has a progressive spring characteristic curve.

15. The intervertebral implant of claim 4 wherein the locking means is configured to operate in a snap-in manner.

16. The intervertebral implant of claim 9 wherein the locking means is configured to operate in a snap-in manner.

17. The intervertebral implant of claim 16 wherein the female dovetail guide has a recess, and the male dovetail guide has a spring element operative to be snapped into the recess.