Apparatus for inserting spinal implants

• US 7,452,359 B1
• Filed: 06/07/1995
• Issued: 11/18/2008
• Est. Priority Date: 06/13/1988
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Michelson, Gary Karlin
• Primary Examiner(s): Brown; Michael A.
• Application Number:
  US08/480,684
• Time in Patent Office: 4,913 Days
• Field of Search: 606/60, 606/61, 606 72- 79, 606 80- 81, 623/16.1, 623/17.1
• US Class Current: 606/60
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/8888 at its central region
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61B 2090/036 abutting on tissue or skin
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• 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 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30785 parallel
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/3085 with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• 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 2002/4619 : for extraction
• 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 2002/4681 : by applying mechanical shocks, e.g. by hammering
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical

Abstract

An artificial spinal implant is disclosed which when placed between two adjacent vertebrae directly participates and is incorporated in the ensuing fusion. Instrumentation and procedure is also disclosed.

Claims

1. An insertion device for inserting an implant into a spine during spinal surgery, said insertion device comprising:

a first member having means for engaging the implant to prevent the implant from moving axially apart from axial movement of said first member; and

a second member having means for engaging the implant to prevent the implant from rotating separate from said second member, said first and second members cooperating to lockably engage the implant such that during insertion of the implant said insertion device can be rotated in either direction, pushed, and pulled by said second member without disengaging the implant from said second member of said insertion device.

2. The insertion device of claim 1, wherein said engaging means of said first member includes a threaded portion.

3. The insertion device of claim 1, wherein said engaging means of said second member includes a depression for receiving a complementing raised portion of the implant.

4. The insertion device of claim 1, wherein the implant has a first cooperating member and said engaging means of said second member comprises a corresponding second cooperating member for cooperatively engaging said first cooperating member.

5. The insertion device of claim 1, further comprising a handle attached to said second member for providing leverage during rotation in either direction, pushing, and pulling of the insertion device.

6. A system for inserting into a spine during spinal surgery an interbody spinal implant, an instrument of said system comprising:

a first portion configured to engage the implant and to impart axial movement to the implant; and

a second portion configured to engage the implant to rotate the implant, said first and second portions cooperating to lockably engage the implant such that during insertion of the implant said instrument can be rotated in either direction, pushed, and pulled by said second portion without disengaging the implant from said second portion of said instrument.

7. The system of claim 6, wherein said first portion includes a thread.

8. The system of claim 6, wherein said second portion includes a depression for receiving a complementary raised portion of the implant.

9. The system of claim 6, wherein the implant has a first cooperating member and said second portion comprises a corresponding second cooperating member for cooperatively engaging the first cooperating member of the implant.

10. The system of claim 6, further comprises a handle attached to said second portion for exerting force during rotation in either direction, pushing, and pulling of the instrument.

11. The system of claim 6, further comprising an implant for promoting fusion between adjacent vertebral bodies, said implant having upper and lower surfaces for placement between and in contact with the adjacent vertebral bodies, each of said upper and lower surfaces having at least one opening adapted to permit bone from the adjacent vertebral bodies to grow through said implant.

12. The system of claim 11, further comprising a hollow between said upper and lower surfaces for holding bone growth promoting material.

13. The system of claim 12, wherein said at least one opening of each of said upper and lower surfaces are in communication with said hollow to permit bone from adjacent vertebral bodies to grow through said implant.

14. The system of claim 11, wherein said implant is made of an implant material other than bone.

15. The system of claim 11, wherein said implant is formed of a material stronger than the adjacent vertebral bodies in contact with said implant.

16. A surgical instrument for inserting a spinal implant into a human spine, said instrument comprising;

a shaft having a proximal end, a distal end opposite said proximal end, and a mid-longitudinal axis through said proximal and distal ends, said distal end having a projection extending therefrom adapted to engage a trailing end of the implant, said projection having a maximum dimension in a plane transverse to the mid-longitudinal axis of said shaft, said distal end having a stepped portion forming an engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft, said engagement wall being configured to contact an engagement surface on the implant, said engagement wall having a maximum dimension transverse to the mid-longitudinal axis of said shaft that is greater than the maximum transverse dimension of said projection.

17. The instrument of claim 16, further comprising at least a second engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft.

18. The instrument of claim 17, wherein said engagement walls are parallel to one another.

19. The instrument of claim 17, wherein said engagement walls define a recess therebetween.

20. The instrument of claim 19, wherein said recess has a minimum dimension transverse to the mid-longitudinal axis of said shaft that is greater than the maximum transverse dimension of said projection.

21. The instrument of claim 17, wherein said engagement walls face each other.

22. The instrument of claim 16, wherein said engagement wall extends to an outer perimeter of said distal end.

23. The instrument of claim 16, wherein said engagement wall extends to an outer perimeter at more than one location along the outer perimeter.

24. The instrument of claim 16, wherein said engagement wall includes a portion that is linear.

25. The instrument of claim 16, wherein said engagement wall has a maximum length transverse to the mid-longitudinal axis of said shaft, said engagement wall being linear along its entire length.

26. The instrument of claim 16, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft, said engagement wall having a maximum length transverse to the mid-longitudinal axis of said shaft that is less than the maximum transverse dimension of said shaft.

27. The instrument of claim 16, wherein said engagement wall has a maximum height parallel to the mid-longitudinal axis of said shaft, said projection extending beyond the maximum height of said engagement wall.

28. The instrument of claim 16, wherein said projection is moveable relative to said engagement wall.

29. The instrument of claim 16, wherein said projection is coaxial with the mid-longitudinal axis of said shaft.

30. The instrument of claim 16, wherein said shaft includes a passage from said proximal end to said distal end.

31. The instrument of claim 30, wherein said projection is a distal end of a rod insertable in said passage.

32. The instrument of claim 16, wherein said projection is adapted to rotationally engage the trailing end of the implant.

33. The instrument of claim 16, wherein said projection includes a thread.

34. The instrument of claim 16, wherein said projection is substantially limited to rotational and axial movement.

35. The instrument of claim 16, wherein said projection has a cross section transverse to the mid-longitudinal axis of said shaft that is circular.

36. The instrument of claim 16, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than twice the transverse maximum dimension of said projection.

37. The instrument of claim 16, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than three times the transverse maximum dimension of said projection.

38. The instrument of claim 30, wherein said shaft has a length and said passage has a variable cross section transverse to the mid-longitudinal axis of said shaft along at least a portion of the length of said shaft.

39. The instrument of claim 30, wherein said projection is moveable relative to said shaft, said passage including a depth stop adapted to limit axial movement of said projection into the implant.

40. The instrument of claim 39, wherein said depth stop includes a shoulder.

41. The instrument of claim 16, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft that becomes larger proximate said distal end of said shaft.

42. The instrument of claim 16, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft proximate said distal end that is adapted to substantially match an outer cross section of the trailing end of the implant.

43. The instrument of claim 16, wherein said distal end includes a planar portion transverse to the mid-longitudinal axis of said shaft.

44. The instrument of claim 16, further comprising a handle adapted to move said projection into engagement with the implant.

45. The instrument of claim 44, wherein said handle is knurled.

46. The instrument of claim 16, wherein said shaft further comprises a handle.

47. The instrument of claim 46, wherein said handle extends transverse to the mid-longitudinal axis of said shaft.

48. The instrument of claim 46, wherein said handle forms a T-shape with said shaft.

49. A surgical instrument for inserting a spinal implant through a hollow sleeve and into a human spine, said instrument comprising;

a shaft adapted to be inserted into the hollow sleeve, said shaft having a proximal end, a distal end opposite said proximal end, a length from said proximal end to said distal end, and a mid-longitudinal axis through said proximal and distal ends, said shaft having a passage from said proximal end to said distal end, said shaft having a depth stop configured to limit insertion of said shaft into the hollow sleeve, said shaft having an outer wall that is parallel to the mid-longitudinal axis along at least a portion of the length of said shaft; and

a rod insertable into said passage of said shaft, said rod having a proximal end and a distal end, said distal end of said rod being configured to engage the implant, said rod when engaged within said shaft having a depth stop limiting axial movement of said shaft within said passage, said depth stop of said rod being a distance from the distal end of said shaft, said depth stop of said shaft being a distance from the distal end of said shaft, the distance of said rod being less than the distance of said shaft.

50. The instrument of claim 49, wherein said distal end of said shaft has a stepped portion forming an engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft, said engagement wall being configured to contact an engagement surface on the implant.

51. The instrument of claim 50, further comprising at least a second engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft.

52. The instrument of claim 51, wherein said engagement walls are parallel to one another.

53. The instrument of claim 51, wherein said engagement walls define a recess therebetween.

54. The instrument of claim 53, wherein said recess has a minimum dimension transverse to the mid-longitudinal axis of said shaft that is greater than the maximum transverse dimension of said rod.

55. The instrument of claim 51, wherein said engagement walls face each other.

56. The instrument of claim 50, wherein said engagement wall extends to an outer perimeter of said distal end.

57. The instrument of claim 50, wherein said engagement wall extends to an outer perimeter at more than one location along the outer perimeter.

58. The instrument of claim 50, wherein said engagement wall includes a portion that is linear.

59. The instrument of claim 50, wherein said engagement wall has a maximum length transverse to the mid-longitudinal axis of said shaft, said engagement wall being linear along its entire length.

60. The instrument of claim 50, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft, said engagement wall having a maximum length transverse to the mid-longitudinal axis of said shaft that is less than the maximum transverse dimension of said shaft.

61. The instrument of claim 50, wherein said engagement wall has a maximum height parallel to the mid-longitudinal axis of said shaft, said rod extending beyond the maximum height of said engagement wall.

62. The instrument of claim 50, wherein said rod is moveable relative to said engagement wall.

63. The instrument of claim 49, wherein said rod is coaxial with the mid-longitudinal axis of said shaft.

64. The instrument of claim 49, wherein said rod is adapted to rotationally engage the trailing end of the implant.

65. The instrument of claim 49, wherein said rod includes a thread.

66. The instrument of claim 49, wherein said rod is substantially limited to rotational and axial movement.

67. The instrument of claim 49, wherein said rod has a cross section transverse to the mid-longitudinal axis of said shaft that is circular.

68. The instrument of claim 49, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than twice the transverse maximum dimension of said rod.

69. The instrument of claim 49, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than three times the transverse maximum dimension of said rod.

70. The instrument of claim 49, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft proximate said distal end that is adapted to substantially match an outer cross section of a trailing end of the implant.

71. The instrument of claim 49, further comprising a handle adapted to move said rod into engagement with the implant.

72. The instrument of claim 71, wherein said handle is knurled.

73. The instrument of claim 49, wherein said shaft further comprises a handle.

74. The instrument of claim 73, wherein said handle extends transverse to the mid-longitudinal axis of said shaft.

75. The instrument of claim 73, wherein said handle forms a T-shape with said shaft.

76. A surgical instrument for inserting a spinal implant into a human spine, said instrument comprising;

a shaft having a proximal end, a distal end opposite said proximal end, and a mid-longitudinal axis through said proximal and distal ends, said distal end having a projection extending therefrom adapted to engage a trailing end of the implant, said distal end having a stepped portion forming an engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft, said engagement wall being configured to contact an engagement surface on the implant, said distal end of said shaft having a maximum width transverse to the mid-longitudinal axis of said shaft, said engagement wall having a dimension in the plane parallel to the mid-longitudinal axis of said shaft that extends across a majority of the width of said distal end of said shaft.

77. The instrument of claim 76, further comprising at least a second engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft.

78. The instrument of claim 77, wherein said engagement walls are parallel to one another.

79. The instrument of claim 77, wherein said engagement walls define a recess therebetween.

80. The instrument of claim 79, wherein said recess has a minimum dimension transverse to the mid-longitudinal axis of said shaft that is greater than the maximum transverse dimension of said projection.

81. The instrument of claim 77, wherein said engagement walls face each other.

82. The instrument of claim 76, wherein said engagement wall extends to an outer perimeter of said distal end.

83. The instrument of claim 76, wherein said engagement wall extends to an outer perimeter at more than one location along the outer perimeter.

84. The instrument of claim 76, wherein said engagement wall includes a portion that is linear.

85. The instrument of claim 76, wherein said engagement wall has a maximum length transverse to the mid-longitudinal axis of said shaft, said engagement wall being linear along its entire length.

86. The instrument of claim 76, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft, said engagement wall having a maximum length transverse to the mid-longitudinal axis of said shaft that is less than the maximum transverse dimension of said shaft.

87. The instrument of claim 76, wherein said engagement wall has a maximum height parallel to the mid-longitudinal axis of said shaft, said projection extending beyond the maximum height of said engagement wall.

88. The instrument of claim 76, wherein said projection is moveable relative to said engagement wall.

89. The instrument of claim 76, wherein said projection is coaxial with the mid-longitudinal axis of said shaft.

90. The instrument of claim 76, wherein said shaft includes a passage from said proximal end to said distal end.

91. The instrument of claim 90, wherein said projection is a distal end of a rod insertable in said passage.

92. The instrument of claim 76, wherein said projection is adapted to rotationally engage the trailing end of the implant.

93. The instrument of claim 76, wherein said projection includes a thread.

94. The instrument of claim 76, wherein said projection is substantially limited to rotational and axial movement.

95. The instrument of claim 76, wherein said projection has a cross section transverse to the mid-longitudinal axis of said shaft that is circular.

96. The instrument of claim 76, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than twice the transverse maximum dimension of said projection.

97. The instrument of claim 76, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than three times the transverse maximum dimension of said projection.

98. The instrument of claim 90, wherein said projection is moveable relative to said shaft, said passage including a depth stop adapted to limit axial movement of said projection into the implant.

99. The instrument of claim 98, wherein said depth stop includes a shoulder.

100. The instrument of claim 76, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft that becomes larger proximate said distal end of said shaft.

101. The instrument of claim 76, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft proximate said distal end that is adapted to substantially match an outer cross section of the trailing end of the implant.

102. The instrument of claim 76, wherein said distal end includes a planar portion transverse to the mid-longitudinal axis of said shaft.

103. The instrument of claim 76, further comprising a handle adapted to move said projection into engagement with the implant.

104. The instrument of claim 103, wherein said handle is knurled.

105. The instrument of claim 76, wherein said shaft further comprises a handle.

106. The instrument of claim 105, wherein said handle extends transverse to the mid-longitudinal axis of said shaft.

107. The instrument of claim 105, wherein said handle forms a T-shape with said shaft.

108. A surgical instrument for inserting a spinal implant into a human spine, said instrument comprising:

a shaft having a proximal end, a distal end opposite said proximal end, a length from said proximal end to said distal end, and a mid-longitudinal axis through said proximal and distal ends, said shaft including a passage from said proximal end to said distal end, said distal end including a planar portion transverse to the mid-longitudinal axis of said shaft, said planar portion being adapted to interdigitate with a trailing end of the implant; and

a rod adapted to rotate within said passage of said shaft, said rod having a proximal end, a distal end configured to engage the implant, and a length from said proximal end to said distal end, the length of said shaft being greater than one-half the length of said rod.

109. The instrument of claim 108, wherein said distal end of said shaft has a stepped portion forming an engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft, said engagement wall being configured to contact an engagement surface on the implant.

110. The instrument of claim 109, further comprising at least a second engagement wall extending in a plane parallel to the mid-longitudinal axis of said shaft.

111. The instrument of claim 110, wherein said engagement walls are parallel to one another.

112. The instrument of claim 110, wherein said engagement walls define a recess therebetween.

113. The instrument of claim 112, wherein said recess has a minimum dimension transverse to the mid-longitudinal axis of said shaft that is greater than the maximum transverse dimension of said rod.

114. The instrument of claim 110, wherein said engagement walls face each other.

115. The instrument of claim 109, wherein said engagement wall extends to an outer perimeter of said distal end.

116. The instrument of claim 109, wherein said engagement wall extends to an outer perimeter at more than one location along the outer perimeter.

117. The instrument of claim 109, wherein said engagement wall includes a portion that is linear.

118. The instrument of claim 109, wherein said engagement wall has a maximum length transverse to the mid-longitudinal axis of said shaft, said engagement wall being linear along its entire length.

119. The instrument of claim 109, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft, said engagement wall having a maximum length transverse to the mid-longitudinal axis of said shaft that is less than the maximum transverse dimension of said shaft.

120. The instrument of claim 109, wherein said engagement wall has a maximum height parallel to the mid-longitudinal axis of said shaft, said rod extending beyond the maximum height of said engagement wall.

121. The instrument of claim 109, wherein said rod is moveable relative to said engagement wall.

122. The instrument of claim 108, wherein said rod is coaxial with the mid-longitudinal axis of said shaft.

123. The instrument of claim 108, wherein said rod is adapted to rotationally engage the trailing end of the implant.

124. The instrument of claim 108, wherein said rod includes a thread.

125. The instrument of claim 108, wherein said rod is substantially limited to rotational and axial movement.

126. The instrument of claim 108, wherein said rod has a cross section transverse to the mid-longitudinal axis of said shaft that is circular.

127. The instrument of claim 108, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than twice the transverse maximum dimension of said rod.

128. The instrument of claim 108, wherein said shaft has a maximum dimension transverse to the mid-longitudinal axis of said shaft that is more than three times the transverse maximum dimension of said rod.

129. The instrument of claim 108, wherein said shaft has a cross section transverse to the mid-longitudinal axis of said shaft proximate said distal end that is adapted to substantially match an outer cross section of a trailing end of the implant.

130. The instrument of claim 108, further comprising a handle adapted to move said rod into engagement with the implant.

131. The instrument of claim 130, wherein said handle is knurled.

132. The instrument of claim 108, wherein said shaft further comprises a handle.

133. The instrument of claim 132, wherein said handle extends transverse to the mid-longitudinal axis of said shaft.

134. The instrument of claim 132, wherein said handle forms a T-shape with said shaft.