Dynamic posterior stabilization systems and methods of use

• US 8,052,723 B2
• Filed: 03/08/2006
• Issued: 11/08/2011
• Est. Priority Date: 08/05/2003
• Status: Expired due to Fees

• Current Assignee: Flexuspine Incorporated
• Original Assignee: Flexuspine Incorporated
• Inventors: Gordon, Charles R., Wagner, Erik J., Hanson, Heather S., Harbold, Corey T.
• Primary Examiner(s): Robert; Eduardo C
• Assistant Examiner(s): NEGRELLIRODRIGUEZ, CHRISTINA
• Application Number:
  US11/371,328
• Publication Number:
  US 20060247635A1
• Time in Patent Office: 2,071 Days
• Field of Search: 606246-267, 606/278, 606/279, 606/379, 606300-321, 623 1711- 1716
• US Class Current: 606/257
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/7005 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit in the screw or hook heads
• CPC Class Codes: A61B 17/7008 with parts of, or attached to, the longitudinal elements, bearing against an outside of the screw or hook heads, e.g. nuts on threaded rods A61B17/7007 takes precedence
• CPC Class Codes: A61B 17/7023 with a pivot joint
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/704 the longitudinal element passing through a ball-joint in the screw head
• CPC Class Codes: A61B 17/7041 with single longitudinal rod offset laterally from single row of screws or hooks A61B17/7044 takes precedence
• CPC Class Codes: A61B 17/7052 of variable angle or length
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 17/746 the longitudinal elements coupled to a plate opposite the femoral head
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61B 17/8897 Guide wires or guide pins
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/4405 for apophyseal or facet joints, i.e. between adjacent spinous or transverse processes devices implanted between spinous or transverse processes A61B17/7062
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30133 : kidney-shaped or bean-shaped
• 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 2002/30369 : Limited lateral translation of the protrusion within a larger recess
• CPC Class Codes: A61F 2002/30462 : retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30492 : using a locking pin
• CPC Class Codes: A61F 2002/30507 : using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30515 : using a locking wedge or block
• CPC Class Codes: A61F 2002/30538 : for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 : for adjusting length
• CPC Class Codes: A61F 2002/30556 : for adjusting thickness
• CPC Class Codes: A61F 2002/30578 : having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30616 : Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30624 : Hinged joint, e.g. with transverse axle restricting the movement
• CPC Class Codes: A61F 2002/30649 : Ball-and-socket joints
• CPC Class Codes: A61F 2002/30662 : with rotation-limiting means
• CPC Class Codes: A61F 2002/3071 : Identification means; Administration of patients
• CPC Class Codes: A61F 2002/30785 : parallel
• 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 2002/443 : having two transversal endplates and at least one intermediate component
• 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 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2250/0007 : for adjusting length
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness
• CPC Class Codes: A61F 2250/0085 : Identification means; Administration of patients
• CPC Class Codes: A61F 2310/00407 : Coating made of titanium or of Ti-based alloys
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61F 2310/00976 : Coating or prosthesis-covering structure made of proteins or of polypeptides, e.g. of bone morphogenic proteins BMP or of transforming growth factors TGF

Abstract

A dynamic posterior stabilization system is provided to stabilize a human spine. In some embodiments, the dynamic posterior stabilization system includes a first bone fastener, a second bone fastener, and an elongated member coupled to the first bone fastener and the second bone fastener. The longitudinal position of the elongated member relative to the first bone fastener may be fixed. The longitudinal position of the second bone fastener relative to the elongated member may vary so that the dynamic posterior stabilization system can accommodate flexion/extension and/or lateral bending. The dynamic posterior stabilization system may also be able to accommodate axial rotation. Bias members may be coupled to the elongated member. The bias members may allow the dynamic posterior stabilization system to mimic the resistance behavior of a normal functional spinal unit.

Claims

1. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second vertebra such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, and wherein at least a portion of the elongated member is configured to pivotably couple to a collar of the first bone fastener such that at least a portion of the elongated member is configured to angulate relative to the first bone fastener; and

at least a portion of a ball configured to be coupled to the elongated member.

2. The posterior stabilization device of claim 1, further comprising a bias member configured to couple to the elongated member, wherein the bias member is positioned to resist flexion of the first vertebra relative to the second vertebra when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second bone fastener.

3. The posterior stabilization device of claim 1, further comprising a bias member configured to couple to the elongated member, wherein the bias member is positioned to resist extension of the first vertebra relative to the second vertebra when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second bone fastener.

4. The posterior stabilization device of claim 1, wherein at least a portion of the elongated member is curved.

5. The posterior stabilization device of claim 1, wherein the elongated member is configured to angulate relative to the first bone fastener such that a height of the elongated member relative to the second bone fastener is variable.

6. The posterior stabilization device of claim 1, wherein rotation of the elongated member relative to the second bone fastener is inhibited, and wherein the ball is configured to be coupled to a collar of the first bone fastener to allow for rotation of the elongated member relative to the first bone fastener to allow for axial rotation of the first vertebra relative to the second vertebra.

7. The posterior stabilization device of claim 1, wherein rotation of the elongated member relative to the first bone fastener is inhibited, and wherein rotation of the elongated member relative to the second bone fastener is allowed to allow for axial rotation of the first vertebra relative to the second vertebra.

8. The posterior stabilization device of claim 1, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length.

9. The posterior stabilization device of claim 1, wherein the ball is configured to couple to the first bone fastener during use, and wherein the ball is configured to rotate relative to the first fastener during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

10. The posterior stabilization device of claim 1, wherein the first bone fastener comprises a socket, and wherein the ball is configured to be positioned in and rotate within the socket during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

11. The posterior stabilization device of claim 1, wherein the elongated member comprises an externally threaded portion, and wherein the ball comprises a complementary internally threaded portion configured to couple to the externally threaded portion of the elongated member during use.

12. The posterior stabilization device of claim 1, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length.

13. The posterior stabilization device of claim 1, wherein a longitudinal axis of the elongated member intersects a center of the ball.

14. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, and wherein at least a portion of the elongated member is configured to angulate relative to the first bone fastener;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member are configured to provide resistance to movement of the second bone fastener relative to the first bone fastener.

15. The posterior stabilization device of claim 14, wherein the elongated member is configured to angulate relative to the first bone fastener such that a height of the elongated member relative to the second bone fastener is variable.

16. The posterior stabilization device of claim 14, wherein the elongated member is configured to pivotably couple to a collar of the first bone fastener.

17. The posterior stabilization device of claim 14, wherein rotation of the elongated member relative to the second bone fastener is inhibited, and comprising a ball coupled to the elongated member, the ball configured to be coupled to a collar of the first bone fastener to allow for rotation of the elongated member relative to the first bone fastener to allow for axial rotation of the first vertebra relative to the second vertebra.

18. The posterior stabilization device of claim 17, wherein the ball is configured to allow angulation of the elongated member relative to the first bone fastener so that a height of the elongated member relative to the second bone fastener is variable.

19. The posterior stabilization device of claim 14, wherein rotation of the elongated member relative to the first bone fastener is inhibited, and wherein rotation of the elongated member relative to the second bone fastener is allowed to allow for axial rotation of the first vertebra relative to the second vertebra.

20. The posterior stabilization device of claim 14, further comprising a ball coupled to the elongated member, wherein a longitudinal axis of the elongated member intersects a center of the ball.

21. The posterior stabilization device of claim 20, wherein the ball is configured to couple to the first bone fastener during use, and wherein the ball is configured to rotate relative to the first fastener during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

22. The posterior stabilization device of claim 20, wherein the first bone fastener comprises a socket, and wherein the ball is configured to be positioned in and rotate within the socket during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

23. The posterior stabilization device of claim 20, wherein the elongated member comprises an externally threaded portion, and wherein the ball comprises a complementary internally threaded portion configured to couple to the externally threaded portion of the elongated member during use.

24. The posterior stabilization device of claim 20, wherein the ball is configured to couple to the first bone fastener during use, and wherein the ball is configured to rotate relative to the first fastener during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

25. The posterior stabilization device of claim 20, wherein the first bone fastener comprises a socket, and wherein the ball is configured to be positioned in and rotate within the socket during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

26. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second vertebra such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, and wherein the elongated member comprises an externally threaded portion; and

at least a portion of a ball configured to be coupled to the elongated member, wherein the ball comprises a complementary internally threaded portion configured to be coupled to the externally threaded portion of the elongated member during use.

27. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, and wherein the elongated member comprises an externally threaded portion;

at least a portion of a ball configured to be coupled to the elongated member, wherein the elongated member comprises an externally threaded portion, and wherein the ball comprises a complementary internally threaded portion configured to be coupled to the externally threaded portion of the elongated member during use;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

28. The posterior stabilization device of claim 27, wherein the ball is configured to couple to the first bone fastener during use, and wherein the ball is configured to rotate relative to the first fastener during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

29. The posterior stabilization device of claim 27, wherein the first bone fastener comprises a socket, and wherein the ball is configured to be positioned in and rotate within the socket during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

30. The posterior stabilization device of claim 27, wherein a longitudinal axis of the elongated member intersects a center of the ball.

31. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second vertebra such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, and wherein the elongated member is configured to be pivotably coupled to a collar of the first bone fastener; and

at least a portion of a ball configured to be coupled to the elongated member.

32. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second vertebra such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, and wherein rotation of the elongated member relative to the second bone fastener is inhibited; and

at least a portion of a ball configured to coupled to the elongated member, and wherein the ball is configured to be coupled to a collar of the first bone fastener to allow for rotation of the elongated member relative to the first bone fastener to allow for axial rotation of the first vertebra relative to the second vertebra.

33. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener when the first bone fastener is coupled to the first vertebra and the second bone fastener is coupled to the second vertebra such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises an externally threaded portion; and

at least a portion of a ball configured to be coupled to the elongated member, and wherein the ball comprises a complementary internally threaded portion configured to couple to the externally threaded portion of the elongated member during use.

34. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, and wherein the elongated member is configured to be pivotably coupled to a collar of the first bone fastener;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

35. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, wherein rotation of the elongated member relative to the second bone fastener is inhibited;

at least a portion of a ball configured to be coupled to the elongated member, the ball configured to be coupled to a collar of the first bone fastener to allow for rotation of the elongated member relative to the first bone fastener to allow for axial rotation of the first vertebra relative to the second vertebra;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

36. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, wherein rotation of the elongated member relative to the first bone fastener is inhibited, and wherein rotation of the elongated member relative to the second bone fastener is allowed to allow for axial rotation of the first vertebra relative to the second vertebra;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

37. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member comprises a rigid elongated member having a longitudinal axis that is curved along at least a portion of its length, wherein the elongated member comprises an externally threaded portion;

at least a portion of a ball configured to be coupled to the elongated member, wherein the ball comprises a complementary internally threaded portion configured to couple to the externally threaded portion of the elongated member during use;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

38. A posterior stabilization device for a human spine, comprising:

a first bone fastener configured to be coupled to a first vertebra;

a second bone fastener configured to be coupled to a second vertebra;

an elongated member configured to couple to the first bone fastener and the second bone fastener such that longitudinal movement of the elongated member relative to the first bone fastener is inhibited and longitudinal movement of the elongated member relative to the second bone fastener is allowed, wherein the elongated member is configured to angulate relative to the first bone fastener;

a first bias member configured to be coupled to the elongated member and positioned between the first bone fastener and the second bone fastener; and

a second bias member configured to be coupled to the elongated member and positioned between the second bone fastener and an end of the elongated member;

wherein the first bias member and the second bias member provide resistance to movement of the second bone fastener relative to the first bone fastener.

39. The posterior stabilization device of claim 38, wherein the elongated member comprises a first elongated member and a second elongated member pivotably coupled to one another.

40. The posterior stabilization device of claim 38, wherein the elongated member comprises a longitudinal axis that is curved along at least a portion of its length proximate an end of the elongated member.

41. The posterior stabilization device of claim 38, further comprising a ball configured to be coupled to the elongated member, the ball configured to be coupled to a collar of the first bone fastener to allow for rotation of the elongated member relative to the first bone fastener.

42. The posterior stabilization device of claim 41, wherein the first bone fastener comprises a socket, and wherein the ball is configured to be positioned in and rotate within the socket during use to facilitate angulation of the elongated member relative to the first bone fastener during use.

43. The posterior stabilization device of claim 41, wherein the elongated member comprises an externally threaded portion, and wherein the ball comprises a complementary internally threaded portion configured to be coupled to the externally threaded portion of the elongated member during use.