TRANSCORPOREAL SPINAL DECOMPRESSION AND REPAIR SYSTEM AND RELATED METHOD

• US 20090076555A1
• Filed: 09/12/2008
• Published: 03/19/2009
• Est. Priority Date: 09/13/2007
• Status: Active Grant

• Current Assignee: Globus Medical, Inc.
• Original Assignee: Transcorp, Inc
• Inventors: Veldman, Roger, Tuinstra, Scott, Lowry, David, O'Farrell, Desmond
• Granted Patent: US 8,323,320 B2
• Time in Patent Office: Days
• US Class Current: 606/280
• CPC Class Codes: A61B 17/1637 Hollow drills or saws producing a curved cut, e.g. cylindrical A61B10/025, A61B17/1695 take precedence
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/686 Plugs, i.e. elements forming interface between bone hole and implant or fastener, e.g. screw
• CPC Class Codes: A61B 17/70 Spinal positioners or stabilisers ; Bone stabilisers comprising fluid filler in an implant
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/809 with bone-penetrating elements, e.g. blades or prongs bone staples A61B17/0642; intramedullary nails with a plate at an end A61B17/7233
• CPC Class Codes: A61B 2090/062 penetration depth
• CPC Class Codes: A61F 2002/4649 Bone graft or bone dowel harvest sites

Abstract

A system and method are provided for making an access channel through a vertebral body to access a site of neural compression, decompressing it, and repairing the channel to restore vertebral integrity. System elements include an implantable vertebral plate, a guidance device for orienting bone cutting tools and controlling the path of a cutting tool, a bone cutting tool to make a channel in the vertebral body, a tool for opening or partially-resecting the posterior longitudinal ligament of the spine, a tool for retrieving a herniated disc, an implantable device with osteogenic material to fill the access channel, and a retention device that lockably-engages the bone plate to retain it in position after insertion. System elements may be included in a surgery to decompress an individual nerve root, the spinal cord, or the cauda equina when compressed, for example, by any of a herniated disc, an osteophyte, a thickened ligament arising from degenerative changes within the spine, a hematoma, or a tumor.

Claims

1. A surgical system to form and repair an access channel through a vertebral body, the channel having an anterior surface entry and a posterior surface opening, the system comprising:

a bone cutting tool with a cutting element;

a bone plate configured to be secured to the anterior surface of the vertebral body; and

a trajectory control sleeve configured to detachably engage the bone plate and having a cylinder configured to receive at least a portion of the bone cutting tool, the bone plate and the trajectory control sleeve, when mutually engaged, configured to cooperate to guide the cutting element to form the access channel with a prescribed trajectory from the anterior entry to the prescribed posterior opening.

2. The surgical system of claim 1 further including fixation elements to secure the bone plate to the anterior surface of the vertebral body, the plate and fixation elements configured such that the bone plate may be permanently implanted.

3. The surgical system of claim 1 wherein the bone plate includes openings to accommodate fixation elements to secure the bone plate to the anterior surface of the vertebral body.

4. The surgical system of claim 1 wherein the trajectory control sleeve is configured to direct the bone cutting tool on the prescribed trajectory, the prescribed trajectory having an angle according to a cranio-caudal axis and a medial lateral axis with respect to a reference plane tangential to the access channel entry on the anterior surface of the vertebral body.

5. The surgical system of claim 4 wherein the angle is a compound angle.

6. The surgical system of claim 1 wherein the bone plate provides a reference surface and wherein the trajectory control sleeve, when secured to the bone plate, may be configured with a range of angles formed with respect to the surface of the bone plate on two axes, a cranio-caudal axis and a medial lateral axis, the range of the angles varying between about 1 degree and about 30 degrees from a perpendicular angle.

7. The surgical system of claim 6 wherein the range of the angle varies between about 10 degrees and about 30 degrees from the perpendicular angle.

8. The surgical system of claim 1 including a plurality of alternately attachable trajectory control sleeves, the sleeves varying in regard to an angle formed with respect to a plane represented by the bone plate when secured thereto, the angles ranging between about 1 degrees and about 30 degrees from a perpendicular angle.

9. The surgical system of claim 1 wherein the trajectory control sleeve and the bone plate have mutually-engageable features that orient the engagement of the trajectory control sleeve on the bone plate in a configuration that allows the trajectory control sleeve to guide the cutting tool through the vertebral body along the prescribed trajectory.

10. The surgical system of claim 1 wherein the trajectory control sleeve includes a contact surface for engaging a corresponding surface on the bone cutting tool, the surfaces configured so as to limit the penetration of the cutting tool into the vertebral body to a prescribed depth.

11. The surgical system of claim 1 wherein the posterior surface of the bone plate includes one or more penetrating elements configured to impinge into the vertebral bone tissue.

12. The surgical system of claim 1 wherein the bone plate includes an anatomically-orienting feature to establish the position of the bone plate relative to the medial centerline of the vertebral body.

13. The surgical system of claim 1 wherein the bone plate includes a biocompatible material.

14. The surgical system of claim 1 wherein at least a posterior surface of the bone plate is of sufficiently porous composition to support in-growth of bone.

15. The surgical system of claim 1 wherein the bone-cutting tool is any of a drill, a ream, a core cutter or a trephine.

16. The surgical system of claim 15 wherein the cutting element of the bone-cutting tool has a cutting diameter between about 5 mm and about 7 mm.

17. The surgical system of claim 1 further comprising an implantable bone repair device having an external geometry complementary to the internal geometry of the access channel.

18. The surgical system of claim 17 wherein the bone repair device is sized to be insertable through an opening of the bone plate, the opening being sized to receive the bone cutting element.

19. The surgical system of claim 17 wherein the bone repair device includes a bio-compatible material.

20. The surgical system of claim 17 wherein the bone repair device includes a bio-absorbable material.

21. The surgical system of claim 17 wherein the bone repair device includes an osteogenic agent.

22. The surgical system of claim 17 wherein the bone repair device and the bone plate have mutually engageable orientation and locking features configured to form a locking engagement.

23. The surgical system of claim 22 wherein the locking engagement results from the application of an axial force to snap the locking feature into a corresponding retaining feature of the bone plate.

24. The surgical system of claim 22 wherein the locking engagement results from the application of a torsional force to engage the locking feature into a corresponding retaining feature in or on the bone plate.

25. The surgical system of claim 17 wherein bone repair device includes receiving features in or on its anterior surface configured to accommodate the attachment of an insertion tool.

26. The surgical system of claim 17 wherein the bone repair device comprises a porous cage with a porosity sufficient to permit through movement of blood and bone cells.

27. The surgical system of claim 26 wherein the composition of the porous cage comprises any of a polymer, a metal, metallic alloy, or a ceramic.

28. The surgical system of claim 27 wherein the polymer of the composition may include polyetheretherketone (PEEK), PEEK-reinforced carbon fiber, or hydroxyapatite-reinforced PEEK.

29. The surgical system of claim 26 wherein the porous cage device includes a closeable opening through which bone material may be passed.

30. The surgical system of claim 26 wherein the porous cage device includes a closeable cap configured to increase pressure within the cage as the cap is closed.

31. The surgical system of claim 26 wherein the porous cage device includes a minimally compressive internal element adapted to enhance compressive force applied to contents of the porous cage upon application of compressive force to the cage.

32. The surgical system of claim 1 further comprising a trajectory and depth visualization device.

33. The surgical system of claim 32 wherein the trajectory and depth visualization device includes a radio-opaque feature to allow confirmation of the location of the bone plate device on the appropriate vertebral body and to facilitate the extrapolation of the projected trajectory of the bone cutting tool using a radiographic image.

34. The surgical system of claim 32 wherein the trajectory and depth visualization device includes visual markings to indicate a distance from a point of contact with the vertebral body and cutter penetration control feature on the bone cutter guide device.

35. A method for performing a procedure through a vertebral body overlaying a site in need of a medical procedure comprising:

attaching a bone plate on an anterior surface of the vertebral body;

engaging a trajectory control sleeve to the bone plate;

inserting at least a portion of a bone cutting tool through the trajectory control sleeve;

forming an access channel with a prescribed trajectory from an entry point on the anterior surface to an opening on the posterior surface of the vertebral body in the locale of the site in need of the procedure by removing bone with the bone cutting tool;

disengaging the trajectory control sleeve from the bone plate; and

performing the medical procedure through the access channel and the opening on the posterior surface of the vertebral body.

37. The method of claim 35 further comprising, after performing the medical procedure, leaving the bone plate attached to the vertebral body.

38. The method of claim 35, after engaging the trajectory control sleeve to the bone plate, further comprising:

inserting a radiopaque locating device into the trajectory control sleeve device, radiographically observing the locating device and determining therefrom an extrapolated trajectory of the access channel toward the posterior surface of the vertebral body; and

verifying that the extrapolated trajectory is consistent with the prescribed trajectory.

39. The method of claim 38 wherein the verifying step includes verifying the extrapolated trajectory of the access channel in a cranio-caudal direction and a medial lateral direction.

40. The method of claim 35, after engaging the trajectory control sleeve to the bone plate, further comprising:

inserting a depth-measuring device into the trajectory control sleeve device to establish an optimal depth of penetration of the bone-cutting tool into the vertebral body, the depth being influenced by the disposition of the bone plate against the anterior surface of the vertebral body.

41. The method of claim 35 wherein performing the medical procedure may include any of performing a medical observation, an exploratory procedure, a diagnostic procedure, a surgical procedure, or a therapeutic delivery procedure.

42. The method of claim 41 wherein performing the surgical procedure includes decompressing a neural element.

43. The method of claim 42 wherein decompressing a neural element may include decompressing any of an individual nerve root, a spinal cord, or a cauda equina.

44. The method of claim 35 wherein the site in need of a medical procedure may include a portion or the whole of a herniated disc, an osteophyte, a thickened ligament, a tumor, a hematoma, a degenerative cyst, or any other compressing pathology.

45. The method of claim 35 wherein the forming the access channel includes forming the channel with a constant, circular cross-section along a single, straight axis aligned with the trajectory control sleeve.

46. The method of claim 35 further comprising, following the medical procedure, repairing the access channel with an implantable bone repair device, the device having an external geometry complementary to the internal geometry of the channel.

47. The method of claim 46 wherein repairing the access channel includes implanting the bone repair device through the bone plate and into the channel.

48. The method of claim 47 further comprising securing a proximal portion of the bone repair device to the bone plate.

49. The method of claim 46 wherein repairing the access channel includes in-growing bone from the vertebral body into at least a portion of the surface of the bone repair device.

50. The method of claim 46 wherein repairing the access channel includes stimulating bone growth within the bone repair device by providing an osteogenic agent within the repair device.

51. The method of claim 46 wherein repairing the access channel includes placing a portion of harvested bone tissue within a bone repair device that comprises a porous cage.

52. The method of claim 51 further comprising allowing intimate contact between the bone tissue within the bone repair device and bone tissue of the vertebral body.

53. The method of claim 51 further comprising perfusing at least some bone tissue or bone-associated biological fluid from the bone repair device into the vertebral body.

54. The method of claim 53 wherein the perfusing step comprises compressing bone tissue inside the porous cage.

55. The method of claim 54 wherein the compressing step is at least partially performed after the porous cage has been placed inside the access channel.

56. The method of claim 51 further comprising allowing the bone tissue within the bone repair device to heal together with the bone tissue of the vertebral body.

36. The method of 35 further comprising, before engaging the trajectory control sleeve to the bone plate, selecting the sleeve to be used such that when the sleeve and the bone plate are engaged, the sleeve has an angle relative to the bone plate that is consistent with the prescribed trajectory of the access channel.

57. A surgical system to form and repair an access channel through a vertebral body, the channel having an anterior surface entry and a posterior surface opening, the system comprising:

a bone cutting tool with a cutting element; and

an integrated device comprising a bone plate portion and trajectory control sleeve portion,

the bone plate portion configured to be secured to an anterior surface of the vertebral body,

the trajectory control sleeve portion having a cylinder configured to receive at least a portion of the bone cutting tool, the integrated device configured to guide the bone cutting tool to form the access channel with a prescribed trajectory from the anterior entry to the prescribed posterior opening.

58. A method for performing a procedure through a vertebral body overlaying a site in need of a medical procedure comprising:

attaching an integrated device comprising a bone plate portion and trajectory control sleeve portion on an anterior surface of the vertebral body;

inserting at least a portion of a bone cutting tool through the trajectory control sleeve;

forming an access channel through the vertebral body by removing bone with the bone cutting tool, the access channel following a prescribed trajectory from an anterior entry point to a prescribed opening on a posterior surface of the vertebral body in the locale of the site in need of the medical procedure;

disengaging the integrated device from the vertebral body; and

performing the medical procedure through the access channel and the opening on the posterior surface of the vertebral body.