Occipito-cervical stabilization system and method

• US 20080086124A1
• Filed: 10/04/2006
• Published: 04/10/2008
• Est. Priority Date: 10/04/2006
• Status: Active Grant

• Current Assignee: Zimmer Biomet Spine, Inc. (Zimvie Incorporated)
• Original Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Jones, Robert J., Forton, Charles R.
• Granted Patent: US 7,901,433 B2
• Time in Patent Office: Days
• US Class Current: 606/60
• CPC Class Codes: A61B 17/7055 connected to sacrum, pelvis or skull

Abstract

A system (10) and associated method are provided for mechanically fixating a region of a skull to a portion of a spine. A plate (20) is provided to contact a region of the skull and be secured thereto. A spinal rod (22) is configured to extend from a location adjacent the plate (20) to a location adjacent at least one vertebra (30). A variable connection (24) is provided to secure the rod (22) to the plate (20). The variable connection (24) has a first mode wherein the relative position of the rod (22) to the plate (20) can be adjusted and a second mode wherein the relative position of the rod (22) to the plate (20) is locked at a particular value selected to maintain a desired curvature of the spine.

Claims

1. A system for mechanically fixating a region of a skull to a portion of a spine, the system comprising:

a plate configured to contact the region of the skull and be secured thereto;

a spinal rod configured to extend from a location adjacent to the plate for connection thereto to a location adjacent at least one vertebra for connection thereto, the rod forming an angle φ

about a transverse axis; and

a variable connection configured to secure the rod to the plate, the connection having a first mode connecting the rod and the plate wherein the angle φ

can be freely varied without requiring deformation of the rod and the plate and a second mode connecting the rod and the plate wherein the rod and the plate are locked at a particular value of the angle φ

selected to maintain a desired curvature of the spine.

2. The system of claim 1 wherein the connection is configured to also allow the rod to be adjusted laterally with respect to the plate in the first mode without requiring deformation of the rod and the plate, and to be locked at a lateral position relative to the plate in the second mode.

3. The system of claim 1 wherein the connection is configured to also allow the rod to be adjusted longitudinally with respect to the plate in the first mode without requiring deformation of the rod and the plate, and to be locked at a longitudinal position relative to the plate in the second mode.

4. The system of claim 1 wherein the connection is configured to allow a second angle formed between the rod and the plate to be adjusted in the first mode without requiring deformation of the rod and the plate, and for the rod and the plate to be locked at a particular value of the angle in the second angle in the second mode.

5. The system of claim 1 wherein the variable connection comprises:

a lateral arm integral with the plate and extending laterally along the transverse axis relative to the spine; and

a connector comprising a body having a transverse opening configured to receive the arm and a longitudinal opening configured to receive a proximate portion of the rod adjacent the plate, the transverse opening configured to pivot about the transverse axis in the first mode and to lock to the arm in the second mode.

6. The system of claim 5 wherein the lateral arm and the transverse opening are configured to also allow the connector to be adjusted laterally with respect to the plate in the first mode without requiring deformation of the rod and the plate, and to be locked at a lateral position relative to the plate in the second mode.

7. The system of claim 5 wherein the longitudinal opening is configured to also allow the rod to be adjusted longitudinally with respect to the plate in the first mode without requiring deformation of the rod and the plate, and to be locked at a longitudinal position relative to the plate in the second mode.

8. The system of claim 5 wherein the lateral arm and the transverse opening are configured to allow a second angle formed between the rod and the plate to be adjusted in the first mode without requiring deformation of the rod and the plate, and for the rod and the plate to be locked at a particular value of the second angle in the second mode.

9. The system of claim 5 wherein:

the body has a lock opening connecting the transverse and longitudinal openings and extending normal to the transverse and longitudinal openings; and

the connector further comprises

a clamp plug configured to be received in the lock opening at a location between the transverse and longitudinal openings; and

a lock configured to engage the lock opening and clamp the clamp plug, the lateral arm, and the rod in the second mode.

10. The system of claim 9 wherein the lateral arm has a first set of spline teeth and the plug has a second set of spline teeth, the first and second sets of spline teeth being disengaged in the first mode and engaged in the second mode.

11. The system of claim 9 wherein the lock has external threads and the locking opening has internal threads that mate with the external threads in both the first and second modes.

12. The system of claim 5 wherein:

the body has first and second lock openings, the first lock opening extending into the transverse opening, and second lock opening extending into the longitudinal opening; and

the connector further comprises first and second locks, the first lock configured to engage the first lock opening and clamp the lateral arm to the body, the second lock configured to engage the second lock opening and clamp the rod to the body.

13. The system of claim 1 further comprising:

a second spinal rod configured to extend from a location adjacent to the plate for connection thereto to a location adjacent at least one vertebra for connection thereto, the first and second rods positioned on laterally opposite sides of the plate from each other; and

a second variable connection configured to secure the second rod to the plate, the second connection having a first mode connecting the second rod and the plate wherein an angle formed between the second rod and the plate can be freely varied without requiring deformation of the second rod and the plate and a second mode connecting the second rod and the plate wherein the second rod and the plate are locked at a particular value of the angle selected to maintain a desired curvature of the spine.

14. A system for mechanically fixating a region of a skull to a portion of a spine, the system comprising:

a plate configured to contact the region of the skull and be secured thereto;

a spinal rod configured to extend from a location adjacent to the plate for connection thereto to a location adjacent at least one vertebra for connection thereto;

a variable connection configured to secure the rod to the plate, the connection having first and second modes connecting the rod and the plate, in the first mode a relative position of the rod and the plate being adjustable with respect to at least four degrees of freedom of motion without requiring deformation of the rod and the plate, in the second mode the rod and the plate being locked in a particular relative position with respect to the at least four degrees of freedom of motion to maintain a desired curvature of the spine.

15. The system of claim 14 wherein the variable connection is configured to allow adjustment of the relative position for the rod and the plate with respect to a fifth degree of freedom of motion in the first mode without requiring deformation of the rod and the plate.

16. The system of claim 14 wherein one of the degrees of freedom of motion is a rotation about a laterally extending axis.

17. The system of claim 16 wherein another one of the degrees of freedom of motion is a rotation about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis.

18. The system of claim 16 wherein another one of the degrees of freedom of motion is a translation along the laterally extending axis.

19. The system of claim 16 wherein another one of the degrees of freedom of motion is a translation along a longitudinally extending axis.

20. The system of claim 16 wherein another one of the degrees of freedom of motion is a rotation about a longitudinally extending axis.

21. The system of claim 16 wherein:

another one of the degrees of freedom of motion is a rotation about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis;

another one of the degrees of freedom of motion is a translation along the laterally extending axis;

another one of the degrees of freedom of motion is a translation along the longitudinally extending axis; and

another one of the degrees of freedom of motion is a rotation about the longitudinally extending axis.

22. The system of claim 14 further comprising:

a second spinal rod configured to extend from a location adjacent to the plate for connection thereto to a location adjacent at least one vertebra for connection thereto, the first and second rods positioned on laterally opposite sides of the plate from each other;

a second variable connection configured to secure the second rod to the plate, the second connection having first and second modes connecting the second rod and the plate, in the first mode a relative position of the second rod and the plate being adjustable with respect to at least four degrees of freedom of motion without requiring deformation of the second rod and the plate, in the second mode the second rod and the plate being locked in a particular relative position with respect to the at least four degrees of freedom of motion to maintain a desired curvature of the spine.

23. A method of coupling a plate to a rod in a system where the plate is to be secured to a region of a skull and the rod is to be secured to at least one vertebra of a spine, the method comprising the steps of:

connecting the rod to the plate so that there is a relative angle φ

formed between the rod and a plane defined by the plate;

adjusting the relative angle φ

to a particular value of the angle φ

selected to maintain a desired curvature of the spine without requiring deformation of the rod or the plate; and

locking the rod and the plate to prevent movement from the particular value of the angle φ

.

24. The method of claim 23 further comprising the step of:

adjusting a lateral position of the rod relative to the plate without requiring deformation of the rod or the plate.

25. The method of claim 23 further comprising the step of:

adjusting a longitudinal position of the rod relative to the plate without requiring deformation of the rod or the plate.

26. The method of claim 23 further comprising the step of:

adjusting an angular position of the rod relative to the plate about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis without requiring deformation of the rod or the plate.

27. The method of claim 23 further comprising the step of:

adjusting an angular position of the rod relative to the plate about a longitudinal axis defined by the rod without requiring deformation of the rod or the plate.

28. The method of claim 23 further comprising at least three of the following steps:

adjusting a lateral position of the rod relative to the plate without requiring deformation of the rod or the plate;

adjusting a longitudinal position of the rod relative to the plate without requiring deformation of the rod or the plate;

adjusting an angular position of the rod relative to the plate about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis without requiring deformation of the rod or the plate; and

adjusting an angular position of the rod relative to the plate about a longitudinal axis defined by the rod without requiring deformation of the rod or the plate.

29. The method of claim 23 wherein the adjusting step is performed after the connecting step and before the locking step.

30. A method of coupling a plate to a rod in a system where the plate is to be secured to a region of a skull and the rod is to be secured to at least one vertebra of a spine, the method comprising the steps of:

connecting the rod to the plate,

adjusting a relative position of the rod and the plate with respect to at least four degrees of freedom of motion; and

locking the rod and the plate at a particular relative position with respect to the at least four degrees of freedom of motion to maintain a desired curvature of the spine.

31. The method of claim 30 wherein one of the degrees of freedom of motion is a rotation about a laterally extending axis.

32. The method of claim 31 wherein another one of the degrees of freedom of motion is a rotation about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis.

33. The method of claim 31 wherein another one of the degrees of freedom of motion is a translation along the laterally extending axis.

34. The method of claim 31 wherein another one of the degrees of freedom of motion is a translation along a longitudinally extending axis.

35. The method of claim 31 wherein another one of the degrees of freedom of motion is a rotation about a longitudinally extending axis.

36. The method of claim 31 wherein:

another one of the degrees of freedom of motion is a rotation about an axis that is perpendicular to both a laterally extending axis and a longitudinally extending axis;

another one of the degrees of freedom of motion is a translation along the laterally extending axis;

another one of the degrees of freedom of motion is a translation along the longitudinally extending axis; and

another one of the degrees of freedom of motion is a rotation about the longitudinally extending axis.

37. The method of claim 30 wherein the adjusting step is performed after the connecting step and before the locking step.