Systems and methods for posterior dynamic stabilization of the spine

• US 20070161991A1
• Filed: 12/20/2005
• Published: 07/12/2007
• Est. Priority Date: 10/20/2004
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Altarac, Moti, Flaherty, J., Tebbe, Shawn
• Granted Patent: US 8,152,837 B2
• Time in Patent Office: Days
• US Class Current: 606/279
• CPC Class Codes: A61B 17/0206 with antagonistic arms as supports for retractor elements
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1697 specially adapted for wire insertion
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/3421 Cannulas
• 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
• CPC Class Codes: A61B 17/7065 Devices with changeable shape, e.g. collapsible or having retractable arms to aid implantation; Tools therefor
• CPC Class Codes: A61B 17/848 Kirschner wires, i.e. thin, long nails
• CPC Class Codes: A61B 17/8866 for gripping or pushing bones, e.g. approximators joint distractors A61B17/025
• CPC Class Codes: A61B 17/8897 Guide wires or guide pins
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: A61B 2017/0023 disposable
• CPC Class Codes: A61B 2017/00261 Discectomy
• CPC Class Codes: A61B 2017/00557 inflatable A61B2017/22051 takes precedence
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61B 2017/681 Alignment, compression, or distraction mechanisms
• CPC Class Codes: A61B 2090/033 Abutting means, stops, e.g. abutting on tissue or skin
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61B 2090/062 penetration depth
• CPC Class Codes: A61B 90/39 : Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/0077 : Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence

Abstract

Devices, systems and methods for dynamically stabilizing the spine are provided. The devices include an expandable spacer having an undeployed configuration and a deployed configuration, wherein the spacer has axial and radial dimensions for positioning between the spinous processes of adjacent vertebrae. The systems include one or more spacers and a mechanical actuation means for delivering and deploying the spacer. The methods involve the implantation of one or more spacers within the interspinous space.

Claims

1. A device for stabilizing at least one spinal motion segment comprising a first vertebra having a first spinous process and a second vertebra having a second spinous process, wherein an interspinous space is defined therebetween, the device comprising:

a body sized and shaped for positioning within the interspinous space; and

at least one extension member movably attached to the body, wherein the at least one extension member can be moved from an undeployed position to a deployed position wherein the device has a first profile when the at least one extension member is in the undeployed position and a second profile when the at least one extension member is in the deployed position, wherein the second profile is greater than the first profile.

2. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member is positioned substantially axially with a longitudinal dimension of the body when in an undeployed position.

3. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member is positioned substantially transverse to a longitudinal dimension of the body when in a deployed position.

4. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member transverses an arc of less than ninety degrees when the at least one extension member moves from the undeployed position to the deployed position.

5. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member transverses an arc of more than ninety degrees when the at least one extension member moves from the undeployed position to the deployed position.

6. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member moves linearly from the undeployed position to the deployed position, wherein said linear motion is along the axis defined by the elongate member.

7. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member includes a flexible covering along at least a portion of its surface.

8. The device of claim 6, wherein the flexible covering includes an elastomeric member.

9. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member includes a hinge element along its length.

10. The device of claim 1, wherein the at least one extension member comprises at least one elongate member wherein said elongate member includes a rotating element along its length.

11. The device of claim 10, wherein the rotating element is resiliently biased.

12. The device of claim 10, wherein the rotating element is configured to rotate the at least one elongate member such that said extension member applies a force to a spinous process.

13. The device of claim 10, wherein the rotatable elongate member is configured to be rotated to apply a force to the spinous process received between the two elongate members.

14. The device of claim 1, wherein the at least one extension member comprises two substantially parallel elongate members spaced to receive an interspinous process therebetween.

15. The device of claim 14, wherein at least one of the substantially parallel elongate members is rotatable in a direction to cause said two elongate members to be nonparallel.

16. The device of claim 14, wherein the rotatable elongate member is configured to be rotated to apply a force to the spinous process received between the two elongate members.

17. The device of claim 1, comprising two extension members wherein the extension members extend from opposite sides of the body when in a deployed position.

18. The device of claim 1, comprising four extension members wherein two extension members are positioned at a proximal end of the body and the other two extension members are positioned at a distal end of the body.

19. The device of claim 18, wherein the distal extension members are configured to distract the spinous processes and the proximal extension members are configured to maintain the device within the interspinous space.

20. The device of claim 1, wherein the at least one extension member is biased in a deployed position.

21. The device of claim 1, wherein the at least one extension member is biased in an undeployed position.

22. The device of claim 1, wherein the at least one extension member is curved.

23. The device of claim 22, wherein the at least one extension member curvature is configured to approximate the curvature of the vertebral element proximate said first vertebra and said second vertebra.

24. The device of claim 1, wherein a portion of the at least one extension member is configured to contact a spinous process when the extension member is in the deployed position.

25. The device of claim 24, wherein said contacting portion is resiliently biased.

26. The device of claim 24, wherein the contacting portion includes an elastomeric member.

27. The device of claim 26, wherein the elastomeric member is covered by a rigid layer.

28. The device of claim 24, wherein the contacting portion provides a first biasing force through a first travel distance and wherein the contacting portion provides a second biasing force through a subsequent travel distance, wherein the second biasing force is greater than the first biasing force.

29. The device of claim 24, wherein the contacting portion is concave.

30. The device of claim 1, wherein the body has a substantially cylindrical configuration.

31. The device of claim 1, wherein the body has a portion configured to contact a spinous process when the at least one extension member is deployed.

32. The device of claim 31, wherein said contacting portion is concave.

33. The device of claim 1, wherein the body is configured to be operably extended from a first length to a second length, said second length providing sufficient distraction between the first spinous process and the second spinous process.

34. The device of claim 33, wherein the body is extended from the first length to the second length when the at least one extension member is moved from the undeployed position to the deployed position.

35. The device of claim 33, wherein the body is extended from the first length to the second length without moving the at least one extension member.

36. The device of claim 33, wherein the body is extended from the first length to the second length with the extension member in the deployed position.

37. The device of claim 1, further comprising attachment means configured to attach said device to a second implanted device.

38. The device of claim 37, wherein the second implanted device is configured to be attached to bone.

39. The device of claim 38, wherein the second implanted device is configured to attach to a third implanted device.

40. The device of claim 1, further comprising a biodegradable portion configured to perform a temporary function.

41. The device of claim 40, wherein the biodegrable portion provides a temporary fixation of the first vertebra and the second vertebra.

42. The device of claim 1, further comprising a fixation element configured to fix the first vertebra and the second vertebra relative to each other.

43. The device of claim 42, wherein the fixation provided by said fixation element is reversible.

44. The device of claim 1, further comprising at least one visualization marker.

45. The device of claim 44, wherein the at least one visualization marker is selected from the group consisting of radiographic markers, ultrasound markers, magnetic markers, optical markers, and combinations thereof.

46. The device of claim 44, wherein at least one marker is located on the body and at least one marker is located on at least one extension member.

47. The device of claim 44, wherein the at least one visualization marker is configured to identify the angle of deployment of the at least one extension member.

48. The device of claim 44, wherein the at least one visualization marker comprises a linear marker.

49. The device of claim 44, wherein the at least one visualization marker is configured to identify the deployed and undeployed positions of the at least one extension member.

50. The device of claim 44, wherein the at least one visualization marker comprises a linear marker.

51. The device of claim 44, wherein the at least one visualization marker comprises a groove in a portion of the device.

52. The device of claim 44, wherein the at least one visualization marker comprises a radiopaque coating on a portion of the device.

53. The device of claim 1, further comprising a coating on a surface of the device.

54. The device of claim 53, wherein the coating is included only on a portion of said surface.

55. The device of claim 53, wherein the coating is configured to prevent adherence of the device to bone.

56. A system for stabilizing at least one spinal motion segment comprising a first vertebra having a first spinous process and a second vertebra having a second spinous process and an interspinous space defined between the first and second spinous processes, the system comprising:

the interspinous device of claim 1;

and

a delivery tool releasably detachable from a proximal end of the device body for delivering the interspinous device to within the interspinous space.

57. The system of claim 56, wherein the interspinous device is configured for delivery by the delivery device through a midline incision.

58. The system of claim 56, wherein the delivery tool is a rod.

59. The system of claim 58, further comprising a cannula through which the interspinous device and rod are translatable.

60. The system of claim 59, wherein the cannula has a distal end configured to dissect tissue.

61. The system of claim 60, wherein the distal end has at least one radially extending blade.

62. The system of claim 60, wherein the distal end is tapered.

63. The system of claim 60, wherein the cannula has a proximal end having a handle by which to manipulate the cannula.

64. The system of claim 56, wherein the delivery device is manipulatable to actuate deployment of the at least one extension member when the interspinous device is operatively attached thereto.

65. The system of claim 56, further comprising a first cannula with a proximal end and a distal end, said first cannula including a cutting element near said distal end.

66. The system of claim 65, further comprising a second cannula configured to pass over said first cannula.

67. The system of claim 66, wherein the interspinous device and the delivery device pass through the second cannula.

68. The system of claim 56, further comprising at least a second interspinous device of claim A1.

69. The system of claim 68, wherein the first interspinous device has a different geometry than the second interspinous device, and either the first interspinous device or the second interspinous device is implanted in a patient.

70. The system of claim 68, wherein the interspinous device implanted in the patient is chosen based on a patient parameter.

71. The system of claim 70, wherein the patient parameter is selected from the group consisting of:

anatomically geometry of the patient;

disease state of the patient;

trauma state of the patient; and

combinations thereof.

72. The system of claim 68, wherein the second interspinous device is attached to a spinous process of the first vertebra or the second vertebra.

73. A method for stabilizing at least one spinal motion segment comprising a first vertebra having a first spinous process and a second vertebra having a second spinous process and an interspinous space defined between the first and second spinous processes, the method comprising:

introducing the device of claim 1 within the interspinous space when in the undeployed configuration; and

deploying the at least one extension member.

74. The method of claim 73, further comprising extending the at least one extension member to selectively distract the spinous processes.

75. The method of claim 73, wherein the step of deploying comprises decoupling the interspinous device from a delivery tool.

76. The method of claim 73, wherein the step of introducing comprises passing the interspinous device through a cannula having a distal end positioned at the interspinous space.

77. The method of claim 76, wherein the step of deploying comprises translating the at least one extension member past the distal end of the cannula wherein the at least one extension member is biased in an undeployed positioned.

78. The method of claim 73, further comprising forming an incision in the skin along the midline above the interspinous space, wherein the introducing the interspinous device comprises inserting the device within the midline incision.

79. The method of claim 73, further comprising forming an incision in the skin laterally of the midline the interspinous space, wherein the introducing the interspinous device comprises inserting the device within the lateral incision.

80. The method of claim 73 wherein the first spinous process and the second spinous process are distracted prior to positioning the interspinous device at the interspinous space.

81. The method of claim 73 wherein the first spinous process and the second spinous process are distracted subsequent to positioning the interspinous device at the interspinous space.

82. The method of claim 73, further comprising distracting the first spinous process and the second spinous process with a separate distraction device.

83. The method of claim 73, further comprising performing an anatomical measurement procedure on the at least one spinal motion segment.

84. The method of claim 83, wherein the measurement procedure is performed with an imaging apparatus.

85. The method of claim 84, wherein the imaging apparatus is selected from the group consisting of:

an x-ray unit, a fluoroscopy unit, an ultrasound device, a CT-Scan unit, an MRI unit and combinations thereof.

86. The method of claim 83, wherein the measurement procedure is performed utilizing a measurement tool inserted through the skin of the patient.

87. The method of claim 73, further comprising the step of adjusting the distraction between the first spinous process and the second spinous process.

88. The method of claim 87, wherein the distraction adjustment is performed after the deployment of the at least one extension member.

89. The method of claim 88, wherein the distraction adjustment is performed more than twenty-four hours after insertion of the device of claim A1 within the interspinous space.

90. The method of claim 73, further comprising accessing the interspinous space through the supraspinous ligament.

91. The method of claim 90, wherein access is made without cutting the ligament crosswise.

92. The method of claim 90, wherein a substantial portion of the ligament fibers remain intact.

93. The method of claim 90, wherein the access is made through a posterior midline incision made at the interspinous space.

94. The method of claim 90, wherein the access is made through an incision made laterally of the interspinous space.

95. The method of claim 90, wherein accessing is accomplished by means of a tool having a bladed distal end.

96. The method of claim 95, wherein the tool comprises a cannula through which the device is introduced into the interspinous space.

97. The method of claim 95, wherein blades of the distal end are vertically aligned with the supraspinous ligament fibers.

98. The method of claim 73, wherein deploying comprises rotationally moving the at least one extension member.

99. The method of claim 98, wherein deploying further comprises linearly moving the at least one extension member.

100. The method of claim 73, wherein deploying further comprises linearly moving the at least one extension member.

101. The method of claim 73, further comprising assessing the deployment of the device and adjusting a position of the device based on the assessment.

102. The method of claim 73, further comprising removing the device from the interspinous space subsequent to deployment of the device.

103. The method of claim 102, wherein the removal of the device is performed at a time at least 24 hours after the deployment.

104. The method of claim 102, wherein the removal of the device is performed with the same instrumentation used to implant the device.

105. A method for treating at least one spinal motion segment comprising a first vertebra having a first spinous process and a second vertebra having a second spinous process and an interspinous space defined between the first and second spinous processes, the method comprising:

introducing a device within the interspinous space;

adjusting at least one of the shape and size of the device;

using the device to statically stabilize the first and second spinous processes relative to each other; and

subsequently using the device to dynamically stabilize the first and second spinous processes relative to each other.

106. The method of claim 105, wherein statically stabilizing comprises anchoring the device to the first and second spinous processes.

107. The method of claim 105, wherein dynamically stabilizing comprises unanchoring the device to the first and second spinous processes.

108. The method of claim 107, wherein at least a portion of the device is biodegradable wherein unanchoring the device comprises degradation of the biodegradable portion of the device.

109. A method for treating at least one spinal motion segment comprising a first vertebra having a first spinous process and a second vertebra having a second spinous process and an interspinous space defined between the first and second spinous processes, the method comprising:

introducing a device within the interspinous space;

adjusting at least one of the shape and size of the device;

using the device to dynamically stabilize the first and second spinous processes relative to each other; and

subsequently using the device to statically stabilize the first and second spinous processes relative to each other.

110. The method of claim 109, wherein statically stabilizing comprises anchoring the device to the first and second spinous processes.