Expandable spinal implant and associated instrumentation

• US 7,655,043 B2
• Filed: 04/29/2005
• Issued: 02/02/2010
• Est. Priority Date: 04/29/2005
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Peterman, Marc M., Moore, Jeffrey D., Geibel, Paul Tucker
• Primary Examiner(s): Barrett; Thomas C
• Assistant Examiner(s): WOODALL, NICHOLAS W
• Application Number:
  US11/117,890
• Publication Number:
  US 20060247771A1
• Time in Patent Office: 1,740 Days
• Field of Search: 606/57, 606/61, 606/72, 606/90, 606/232, 623/13.15, 623/17.11, 623/17.15, 623/17.16, 623/23.47
• US Class Current: 623/17.11
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• 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 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/30828 parallel
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30892 parallel
• CPC Class Codes: A61F 2002/448 comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2002/4627 with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4629 connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00179 Ceramics or ceramic-like structures

Abstract

An expandable spinal implant including an implant body transitionable between an initial configuration and an expanded configuration. The implant body includes first and second axial walls spaced apart along a transverse axis, with at least one of the walls including first and second axial wall portions laterally offset from one another. An expansion member co-acts with the first wall portion to outwardly displace the first wall portion relative to the second wall portion to transition the implant body to the expanded configuration. In another embodiment, the first wall portion defines a recessed region relative to the second wall portion when the implant body is in the initial configuration, and wherein the recessed region is outwardly expanded as the implant body is transitioned to the expanded configuration. In a further embodiment, the first wall portion is movable while the second wall portion remains substantially stationary.

Claims

1. An expandable spinal implant, comprising:

an implant body having a longitudinal axis and being transitionable between an initial configuration and an expanded configuration, said implant body including first and second ends and first and second axial walls extending along a length of said implant body and spaced apart along a transverse axis extending along a height of said implant body, at least one of said axial walls including first and second axial wall portions laterally offset from one another along a width of said implant body, said first axial wall portion positioned laterally adjacent said second axial wall portion, said first and second axial wall portions extending continuously and substantially entirely along said length of said implant body from said first end to said second end and being flexibly deformable to facilitate flexible deformation of said first axial wall portion; and

an expansion member co-acting with said first axial wall portion to flexibly deform said first axial wall portion and outwardly displace a central region of said first axial wall portion relative to said second axial wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration, said expansion member engaged with said central region of said first axial wall portion in said expanded configuration; and

wherein said implant body includes first and second transverse end walls interconnecting opposite end portions of said first axial wall with opposite end portions of said second axial wall, and wherein said first and second axial wall portions each extend continuously from said first transverse end wall to said second transverse end wall.

2. An expandable spinal implant, comprising:

an implant body having a longitudinal axis and being transitionable between an initial configuration and an expanded configuration, said implant body including first and second ends and first and second axial walls extending along a length of said implant body and spaced apart along a transverse axis extending along a height of said implant body, at least one of said axial walls including first and second axial wall portions laterally offset from one another along a width of said implant body, said first axial wall portion positioned laterally adjacent said second axial wall portion, said first and second axial wall portions extending continuously and substantially entirely along said length of said implant body from said first end to said second end and being flexibly deformable to facilitate flexible deformation of said first axial wall portion; and

an expansion member co-acting with said first axial wall portion to flexibly deform said first axial wall portion and outwardly displace a central region of said first axial wall portion relative to said second axial wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration, said expansion member engaged with said central region of said first axial wall portion in said expanded configuration.

3. The implant of claim 2, wherein said second axial wall portion remains substantially stationary relative to said first axial wall portion as said implant body is transitioned from said initial configuration to said expanded configuration.

4. The implant of claim 2, wherein said first axial wall portion is positioned proximately adjacent said second axial wall portion.

5. The implant of claim 2, wherein said first axial wall portion defines a recessed region relative to said second axial wall portion when said implant body is in said initial configuration;

and

wherein said recessed region is outwardly expanded generally along said transverse axis as said implant body is transitioned from said initial configuration to said expanded configuration.

6. The implant of claim 2, wherein said at least one of said axial walls includes a third axial wall portion laterally offset from said second axial wall portion with said first and third axial wall portions positioned on opposite sides of said second axial wall portion;

and

wherein said expansion member co-acts with each of said first and third axial wall portions to outwardly displace said first and third axial wall portions relative to said second axial wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration.

7. The implant of claim 6, wherein said second axial wall portion remains substantially stationary relative to said first and third axial wall portions as said implant body is transitioned from said initial configuration to said expanded configuration.

8. The implant of claim 6, wherein each of said first and third axial wall portions includes an outer surface and a number of surface protrusions projecting outwardly therefrom, said surface protrusions at least partially positioned inward of an outer surface of said second axial wall portion when said implant body is in said initial configuration.

9. The implant of claim 2, wherein said first axial wall portion includes a first outer surface that is inwardly recessed relative to a second outer surface of said second axial wall portion when said implant body is in said initial configuration.

10. The implant of claim 9, wherein said first outer surface of said first axial wall portion is substantially aligned with said second outer surface of said second axial wall portion when said implant body is transitioned to said expanded configuration.

11. The implant of claim 9, wherein said first axial wall portion includes a number of surface protrusions projecting outwardly from said first outer surface, at least a portion of said surface protrusions being inwardly recessed relative to said second outer surface of said second axial wall portion when said implant body is in said initial configuration.

12. The implant of claim 11, wherein said surface protrusions comprise teeth adapted for engagement with vertebral bone.

13. The implant of claim 11, wherein said surface protrusions are entirely inwardly recessed relative to said second outer surface of said second axial wall portion when said implant body is in said initial configuration.

14. The implant of claim 11, wherein said surface protrusions are at least partially positioned outward of said second outer surface of said second axial wall portion when said implant body is transitioned to said expanded configuration.

15. The implant of claim 2, wherein one of said first and second axial wall portions defines a slot having a length extending generally along said longitudinal axis;

and

wherein said expansion member includes a body portion positioned within said slot and a side portion positioned between said first and second axial walls such that axial movement of said expansion member generally along said longitudinal axis displaces said body portion along said length of said slot and displaces said side portion between said axial walls to outwardly displace said first axial wall portion relative to said second axial wall portion, said body portion sized for sliding engagement along opposing side surfaces of said slot to guide said expansion member generally along said longitudinal axis during said axial movement.

16. The implant of claim 15, wherein said at least one of said axial walls includes a third axial wall portion laterally offset from said second axial wall portion with said first and third axial wall portions positioned on opposite sides of said second axial wall portion;

and

wherein said expansion member includes a pair of said side portions extending in generally opposite directions relative to said body portion, each of said side portions at least partially positioned between said axial walls such that axial movement of said expansion member generally along said longitudinal axis displaces said side portions of said expansion member between said axial walls to outwardly displace said first and third axial wall portions relative to said second axial wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration.

17. The implant of claim 2, wherein said implant body includes leading and trailing end portions positioned generally along said longitudinal axis, said leading end portion having a rounded outer profile to facilitate insertion into an intervertebral disc space.

18. The implant of claim 2, wherein said first axial wall portion defines a recessed region relative to said second axial wall portion when said implant body is in said initial configuration;

and

wherein said recessed region of said first axial wall portion is outwardly expanded generally along said transverse axis relative to said second axial wall portion as said implant body is transitioned from said initial configuration to said expanded configuration.

19. The implant of claim 18, wherein said second axial wall portion remains substantially stationary relative to said first axial wall portion as said implant body is transitioned from said initial configuration to said expanded configuration.

20. The implant of claim 18, wherein said recessed region extends along substantially an entire length of said at least one of said axial walls.

21. The implant of claim 18, wherein the first axial wall portion is positioned proximately adjacent said second axial wall portion.

22. The implant of claim 18, wherein said recessed region extends along substantially an entire length of said at least one of said axial walls between said pair of opposite end portions.

23. The implant of claim 18, wherein said first axial wall portion includes a number of surface protrusions projecting outwardly from said recessed region, at least a portion of said surface protrusions being inwardly recessed relative to an outer surface of said second axial wall portion when said implant body is in said initial configuration.

24. The implant of claim 23, wherein said surface protrusions are entirely inwardly recessed relative to said outer surface of said second axial wall portion when said implant body is in said initial configuration.

25. The implant of claim 18, wherein said recessed region defined by said first axial wall portion comprises a convex curvature extending outwardly along said transverse axis and along substantially an entire length of said at least one of said axial walls.

26. The implant of claim 18, wherein said at least one of said axial walls includes a third axial wall portion laterally offset from said second axial wall portion with said first and third axial wall portions positioned on opposite sides of said second axial wall portion, each of said first and third axial wall portions defining a corresponding one of said recessed regions when said implant body is in said initial configuration;

and

wherein said expansion member co-acts with each of said first and third axial wall portions to transition said implant body from said initial configuration to said expanded configuration wherein said recessed regions are outwardly expanded generally along said transverse axis.

27. The implant of claim 26, wherein said second axial wall portion remains substantially stationary relative to said first and third axial wall portions as said implant body is transitioned from said initial configuration to said expanded configuration.

28. The implant of claim 26, wherein each of said first and third axial wall portions includes a number of surface protrusions projecting outwardly from said recessed regions, at least a portion of said surface protrusions being inwardly recessed relative to an outer surface of said second axial wall portion when said implant body is in said initial configuration.

29. The implant of claim 18, wherein said first axial wall portion includes a first outer surface that is inwardly positioned relative to a second outer surface of said second axial wall portion when said implant body is in said initial configuration to define said recessed region.

30. The implant of claim 29, wherein said first outer surface of said first axial wall portion is substantially aligned with said second outer surface of said second axial wall portion when said implant body is in said expanded configuration.

31. The implant of claim 29, wherein said first axial wall portion includes a number of surface protrusions projecting outwardly from said first outer surface, at least a portion of said surface protrusions being inwardly recessed relative to said second outer surface of said second axial wall portion when said implant body is in said initial configuration.

32. The implant of claim 31, wherein said surface protrusions are entirely inwardly recessed relative to said second outer surface of said second axial wall portion when said implant body is in said initial configuration.

33. The implant of claim 2, wherein said first and second axial wall portions each extend continuously along an entire length of said implant body from said first end to said second end.

34. The implant of claim 2, wherein said first end of said implant body comprises a leading distal end portion and said second end of implant body comprises a trailing proximal end portion of said implant body, and wherein said first and second axial wall portions each extend continuously from said leading distal end portion to said trailing proximal end portion.

35. The implant of claim 2, wherein said implant body includes first and second transverse end walls, and wherein said first and second axial wall portions each extend continuously from said first transverse end wall to said second transverse end wall.

36. An expandable spinal implant, comprising:

an implant body having a longitudinal axis and being transitionable between an initial configuration and an expanded configuration, said implant body including first and second ends and first and second axial walls extending along a length of said implant body and spaced apart along a transverse axis extending along a height of said implant body, at least one of said axial walls including a movable wall portion and a substantially stationary wall portion laterally offset from one another along a width of said implant body, said movable wall portion positioned laterally adjacent said substantially stationary wall portion, said movable and stationary wall portions extending continuously and substantially entirely along said length of said implant body from said first end to said second end and being flexibly deformable to facilitate flexible deformation of said movable wall portion; and

an expansion member co-acting with said movable wall portion to flexibly deform said movable wall portion and outwardly displace a central region of said movable wall portion relative to said stationary wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration, said expansion member engaged with said central region of said movable wall portion in said expanded configuration; and

wherein said implant body includes first and second transverse end walls interconnecting opposite end portions of said first axial wall with opposite end portions of said second axial wall, and wherein said movable and stationary wall portions each extend continuously from said first transverse end wall to said second transverse end wall.

38. The implant of claim 36, wherein said movable wall portion defines a recessed region relative to said stationary wall portion when said implant body is in said initial configuration;

and

wherein said recessed region is outwardly expanded generally along said transverse axis as said implant body is transitioned from said initial configuration to said expanded configuration.

37. An expandable spinal implant, comprising:

an implant body having a longitudinal axis and being transitionable between an initial configuration and an expanded configuration, said implant body including first and second ends and first and second axial walls extending along a length of said implant body and spaced apart along a transverse axis extending along a height of said implant body, at least one of said axial walls including a movable wall portion and a substantially stationary wall portion laterally offset from one another along a width of said implant body, said movable wall portion positioned laterally adjacent said substantially stationary wall portion, said movable and stationary wall portions extending continuously and substantially entirely along said length of said implant body from said first end to said second end and being flexibly deformable to facilitate flexible deformation of said movable wall portion; and

an expansion member co-acting with said movable wall portion to flexibly deform said movable wall portion and outwardly displace a central region of said movable wall portion relative to said stationary wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration, said expansion member engaged with said central region of said movable wall portion in said expanded configuration.

39. The implant of claim 37, wherein the movable wall portion is positioned proximately adjacent said stationary wall portion.

40. The implant of claim 37, wherein said at least one of said axial walls includes a pair of said movable wall portions positioned on opposite sides of said stationary wall portion;

and

wherein said expansion member co-acts with each of said movable wall portions to outwardly displace said movable wall portions relative to said stationary wall portion generally along said transverse axis to transition said implant body from said initial configuration to said expanded configuration.

41. The implant of claim 37, wherein said movable wall portion includes a first outer surface that is inwardly recessed relative to a second outer surface of said stationary wall portion when said implant body is in said initial configuration.

42. The implant of claim 37, wherein said implant body includes leading and trailing end portions positioned generally along said longitudinal axis, said leading end portion having a bullet-shaped configuration to facilitate insertion into an intervertebral disc space.

43. The implant of claim 37, wherein said movable and stationary wall portions each extend continuously along an entire length of said implant body from said first end to said second end.

44. The implant of claim 37, wherein said first end of said implant body comprises a leading distal end portion and said second end of implant body comprises a trailing proximal end portion of said implant body, and wherein said movable and stationary wall portions each extend continuously from said leading distal end portion to said trailing proximal end portion.

45. The implant of claim 37, wherein said implant body includes first and second transverse end walls, and wherein said movable and stationary wall portions each extend continuously from said first transverse end wall to said second transverse end wall.