Hemi-interbody spinal implant manufactured from a major long bone ring or a bone composite

• US 6,989,031 B2
• Filed: 04/02/2002
• Issued: 01/24/2006
• Est. Priority Date: 04/02/2001
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Michelson, Gary K.
• Primary Examiner(s): Philogene, Pedro
• Application Number:
  US10/112,745
• Publication Number:
  US 20020161442A1
• Time in Patent Office: 1,393 Days
• Field of Search: 623/17.11, 623/17.12, 623/17.13, 623/17.14, 623/17.15, 623/17.16, 623/23.63, 623/23.61, 623/23.5, 623/901, 606/61
• US Class Current: 623/17.11
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• 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 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30192 J-shaped
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30836 knurled
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• 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 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0041 J-shaped
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite

Abstract

An interbody spinal implant comprising cortical bone having a width less than one-half the width of the disc space into which it is adapted to be inserted. The implant has a leading end that is asymmetrical from side to side and/or includes a straight portion adapted to be used in side-by-side pairs.

Claims

1. An interbody spinal implant made of conical bone for insertion at least in part into an implantation space formed across the height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect and a posterior aspect, said implant comprising:

a leading end for insertion first into the disc space, a trailing end opposite said leading end, said implant having a length along a mid-longitudinal axis of said implant from said leading end to said trailing end;

opposed upper and lower portions between said leading and trailing ends adapted to be placed at least in part within and across the height of the disc space to contact and support the adjacent vertebral bodies, said upper and lower portions being non-arcuate along at least a portion of the length of said implant;

an interior facing side, an exterior facing side opposite said interior side, and a maximum width therebetween, said maximum width of said implant being less than approximately one-half of the width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said Interior and exterior sides connecting said upper and lower portions and said leading and trailing ends, said leading end having a generally straight portion from side to side, a portion of said exterior side being in a plane generally parallel to the mid-longitudinal axis, said portion of said exterior side intersecting said generally straight portion of said leading end and forming a corner with said generally straight portion of said leading end, said interior side adapted to be oriented toward an interior side of another implant when inserted within the disc space;

said trailing end being adapted to conform from side to side to at least a portion of the peripheral contour of at least one of the anterior and posterior aspects of the vertebral bodies adjacent a disc space into which said implant is inserted;

said implant being manufactured from a bone ring obtained from a major long bone of a human having a medullary canal, said interior side of said implant including at least a portion of the medullary canal so that when said implant is placed side by side another implant having an interior side including at least a portion of a medullary canal a passage is formed adapted to hold bone growth promoting material for permitting for the growth of bone from vertebral body to vertebral body through said passage.

2. The implant of claim 1, wherein said straight portion of said leading end is generally oriented at 90 degrees to the mid-longitudinal axis of said implant.

3. The implant of claim 1, wherein at least a portion of said leading end has a reduced height to facilitate insertion of said implant between the two adjacent vertebral bodies.

4. The implant of claim 1, wherein said trailing end is at least in part straight from side to side.

5. The implant of claim 1, wherein said trailing end is configured in the shape of a half circle from side to side.

6. The implant of claim 1, wherein said trailing end is asymmetrical side to side.

7. The implant of claim 1, wherein said interior side is at least in part straight.

8. The implant of claim 1, wherein said interior side is at least in part oriented generally parallel to the mid-longitudinal axis of said implant.

9. The implant of claim 1, wherein said interior and exterior sides are at least in part generally parallel one another.

10. The implant of claim 1, wherein at least a portion of said upper and lower surfaces are in an angular relationship to each other from trailing end to leading end for allowing angulation of the adjacent vertebral bodies relative to each other.

11. The implant of claim 1, wherein said upper and ower surfaces include at least one opening in communication with one another to permit for the growth of bone from vertebral body to vertebral body through said implant.

12. The implant of claim 1, wherein said implant has a maximum length less than and approximating the posterior to anterior depth of the vertebral bodies.

13. The implant of claim 1, further comprising a bone engaging surface formed on the exterior of at least said upper and lower portions for engaging the adjacent vertebral bodies, said bone engaging surface including at least one of a protrusion, a ratchet, a spike, a spline, surface roughenings, and knurling.

14. The implant of claim 1, wherein said implant comprises at least in part of a bone growth promoting material.

15. The implant of claim 14, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

16. The implant of claim 1, in combination with a bone growth promoting material.

17. The implant of claim 16, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

18. The implant of claim 1, wherein said implant is treated with a bone growth promoting substance.

19. The implant of claim 1, wherein said implant is at least in part resorbable.

20. The implant of claim 1, in combination with a chemical substance adapted to inhibit scar formation.

21. The implant of claim 1, in combination with an antimicrobial material.

22. The implant of claim 1, wherein at least a portion of said implant is treated to promote bone ingrowth between said implant and said adjacent vertebral bodies.

23. The implant of claim 1, further in combination with at least one spinal fixation implant.

24. The implant of claim 1, wherein said trailing end is curved from side to side along a majority of the width of said implant.

25. The implant of claim 1, wherein said implant has a maximum length greater than the maximum width of said implant.

26. The implant of claim 13, wherein said bone engaging surface includes a plurality of ratchets, said ratchets being at least in part forward-facing.

27. The implant of claim 1, wherein said implant has a horizontal mid-longitudinal plane, each of said upper and lower surfaces being in angular relationship relative to the horizontal mid-longitudinal plane of said implant to allow for angulation of the adjacent vertebral bodies relative to each other.

28. An interbody spinal implant made of cortical bone for insertion at least in part across the height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect and a posterior aspect, said implant comprising:

a leading end for insertion first into the disc space, a trailing end opposite said leading end, said implant having a length along a mid-longitudinal axis of said implant from said leading end to said trailing end;

opposed upper and lower portions between said leading and trailing ends adapted to be placed at least in part within and across the height of the disc space to contact and support the adjacent vertebral bodies;

an interior side, an exterior side opposite said interior side, and a maximum width therebetween, said maximum width of said implant being less than one-half of the width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said interior and exterior sides connecting said upper and lower portions and said leading and trailing ends, said leading end having a shape that is asymmetrical from side to side, said trailing end having a shape from side to side different than the shape of said leading end, said interior side adapted to be oriented toward an interior side of another implant when inserted within the disc space, said upper and lower portions being non-arcuate from side to side;

said implant being manufactured from a bone ring obtained from a major long bone of a human having a medullary canal, said interior side of said implant including at least a portion of the medullary canal so that when said implant is placed side by side another implant having an interior side including at least a portion of a medullary canal a passage is formed adapted to hold bone growth promoting material for permitting for the growth of bone from vertebral body to vertebral body through said passage.

29. The implant of claim 28, wherein said leading end includes a generally straight portion from side to side.

30. The implant of claim 29, wherein said straight portion of said leading end is generally oriented at 90 degrees to the mid-longitudinal axis of said implant.

31. The implant of claim 28, wherein at least a portion of said leading end has a reduced height to facilitate insertion of said implant between the two adjacent vertebral bodies.

32. The implant of claim 28, wherein said trailing end is at least in part straight from side to side.

33. The implant of claim 28, wherein said trailing end is configured in the shape of a half circle from side to side.

34. The implant of claim 28, wherein said trailing end is asymmetrical side to side.

35. The implant of claim 28, wherein the trailing end is adapted to conform from side to side to at least a portion of the peripheral contour of at least one of the anterior and posterior aspects of the vertebral bodies adjacent a disc space into which said implant is inserted.

36. The implant of claim 28, wherein said at least one of said interior and exterior sides is at least in part straight.

37. The implant of claim 28, wherein at least one of said interior and exterior sides is at least in part oriented generally parallel to the mid-longitudinal axis of said implant.

38. The implant of claim 28, wherein said interior and exterior sides are at least in part generally parallel one another.

39. The implant of claim 28, wherein at least a portion of said upper and lower surfaces are in an angular relationship to each other from trailing end to leading end for allowing angulation of the adjacent vertebral bodies relative to each other.

40. The implant of claim 28, wherein said upper and lower surfaces include at least one opening in communication with one another to permit for the growth of bone from vertebral body to vertebral body through said implant.

41. The implant of claim 28, wherein said implant has a maximum length less than and approximating the posterior to anterior depth of the vertebral bodies.

42. The implant of claim 28, further comprising a bone engaging surface formed on the exterior of at least said upper and lower portions for engaging the adjacent vertebral bodies, said bone engaging surface including at least one of a protrusion, a ratchet, a spike, a spline, surface roughenings, and knurling.

43. The implant of claim 28, wherein said implant comprises at least in part of a bone growth promoting material.

44. The implant of claim 43, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

45. The implant of claim 28, in combination with a bone growth promoting material.

46. The implant of claim 45, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

47. The implant of claim 28, wherein said implant is treated with a bone growth promoting substance.

48. The implant of claim 28, wherein said implant is at least in part resorbable.

49. The implant of claim 28, in combination with a chemical substance adapted to inhibit scar formation.

50. The implant of claim 28, in combination with an antimicrobial material.

51. The implant of claim 28, wherein at least a portion of said implant is treated to promote bone ingrowth between said implant and said adjacent vertebral bodies.

52. The implant of claim 28, further in combination with at least one of a spinal fixation implant.

53. The implant of claim 28, wherein said trailing end is curved from side to side along a majority of the width of said implant.

54. The implant of claim 28, wherein said implant has a maximum length greater than the maximum width of said implant.

55. The implant of claim 42, wherein said bone engaging surface includes a plurality of ratchets, said ratchets being at least in part forward-facing.

56. The implant of claim 28, wherein said implant has a horizontal mid-longitudinal plane, each of said upper and lower surfaces being in angular relationship relative to the horizontal mid-longitudinal plane of said implant to allow for angulation of the adjacent vertebral bodies relative to each other.

57. The implant of claim 28, wherein said implant includes at least 40 percent of the bone ring from which it is being formed.

58. The implant of claim 29, wherein each of said leading end and said trailing end is at least in part curved from side to side, the curve of said leading end having a radius of curvature different than the radius of curvature of said trailing end.

59. An interbody spinal implant made of bone composite material for insertion at least in part into an implantation space formed across the height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect and a posterior aspect, said implant comprising:

a leading end for insertion first into the disc space, a trailing end opposite said leading end, said implant having a length along a mid-longitudinal axis of said implant from said leading end to said trailing end;

opposed upper and lower portions between said leading and trailing ends adapted to be placed within the disc space to contact and support the adjacent vertebral bodies, said upper and lower portions being non-arcuate along at least a portion of the length of said implant;

an interior side, an exterior side opposite said interior side, and a maximum width therebetween, said maximum width of said implant being less than approximately one-half of the width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said interior and exterior sides connecting said upper and lower portions and said leading and trailing ends, said leading end having a generally straight portion from side to side, a portion of said exterior side being in a plane generally parallel to the mid-longitudinal axis, said portion of said exterior side intersecting said generally straight portion of said leading end and forming a corner with said generally straight portion of said leading end, said interior side adapted to be oriented toward an interior side of another implant when inserted within the disc space;

said trailing end being adapted to conform from side to side to at least a portion of the peripheral contour of at least one of the anterior and posterior aspects of the vertebral bodies adjacent a disc space into which said implant is inserted;

said implant being manufactured from a bone composite material, said interior side of said implant including a recess so that when said implant is placed side by side another implant having an interior side including a recess a passage is formed adapted to hold bone growth promoting material for permitting for the growth of bone from vertebral body to vertebral body through said passage.

60. The implant of claim 59, wherein said bone composite material includes at least one of cortical bone fibers, bone filaments, bone particles and bone dust.

61. The implant of claim 59, further comprising a binding material.

62. The implant of claim 61, wherein said binding material is at least one of bioactive and bioresorbable.

63. The implant of claim 59, wherein said straight portion of said leading end is generally oriented at 90 degrees to the mid-longitudinal axis of said implant.

64. The implant of claim 59, wherein at least a portion of said leading end has a reduced height to facilitate insertion of said implant between the two adjacent vertebral bodies.

65. The implant of claim 59, wherein said trailing end is at least in part straight from side to side.

66. The implant of claim 59, wherein said trailing end is configured in the shape of a half circle from side to side.

67. The implant of claim 59, wherein said trailing end is asymmetrical side to side.

68. The implant of claim 59, wherein said interior side is at least in part straight.

69. The implant of claim 59, wherein said interior side is at least in part oriented generally parallel to the mid-longitudinal axis of said implant.

70. The implant of claim 59, wherein said interior and exterior sides are at least in part generally parallel one another.

71. The implant of claim 59, wherein at least a portion of said upper and lower surfaces are in an angular relationship to each other from trailing end to leading end for allowing angulation of the adjacent vertebral bodies relative to each other.

72. The implant of claim 59, wherein said upper and lower surfaces include at least one opening in communication with one another to permit for the growth of bone from vertebral body to vertebral body through said implant.

73. She implant of claim 59, wherein said implant has a maximum length less than and approximating the posterior to anterior depth of the vertebral bodies.

74. The implant of claim 59, further comprising a bone engaging surface formed on the exterior of at least said upper and lower portions for engaging the adjacent vertebral bodies, said bone engaging surface including at least one of a protrusion, a ratchet, a spike, a spline, surface roughenings, and knurling.

75. The implant of claim 59, wherein said implant comprises at least in part of a bone growth promoting material.

76. The implant of claim 75, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

77. The implant of claim 59, in combination with a bone growth promoting material.

78. The implant of claim 77, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

79. The implant of claim 59, wherein said implant is treated with a bone growth promoting substance.

80. The implant of claim 59, wherein said implant is at least in part resorbable.

81. The implant of claim 59, in combination with a chemical substance adapted to inhibit scar formation.

82. The implant of claim 59, in combination with an antimicrobial material.

83. The implant of claim 59, wherein at least a portion of said implant is treated to promote bone ingrowth between said implant and said adjacent vertebral bodies.

84. The implant of claim 59, further in combination with at least one spinal fixation implant.

85. The implant of claim 59, wherein said trailing end is curved from side to side along a majority of the width of said implant.

86. The implant of claim 59, wherein said implant has a maximum length greater than the maximum width of said implant.

87. The implant of claim 74, wherein said bone engaging surface includes a plurality of ratchets, said ratchets being at least in part forward-facing.

88. The implant of claim 59, wherein said implant has a horizontal mid-longitudinal plane, each of said upper and lower surfaces being in angular relationship relative to the horizontal mid-longitudinal plane of said implant to allow for angulation of the adjacent vertebral bodies relative to each other.

89. A pair of interbody spinal implants made of a bone composite material for insertion at least in part across the height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect, a posterior aspect, and a depth therebetween, each of said implants comprising:

a leading end for insertion first into the disc space, a trailing end opposite said leading end, said implant having a length along a mid-longitudinal axis of said implant from said leading end to said trailing end, said length of said implant being greater than one half the depth of the vertebral bodies adjacent the disc space into which said implant is adapted to be inserted;

opposed upper and lower portions between said leading and trailing ends adapted to be placed at least in part within and across the height of the disc space to contact and support the adjacent vertebral bodies;

an interior side, an exterior side opposite said interior side, and a maximum width therebetween, said maximum width of said implant being less than approximately one-half of the width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said interior and exterior sides connecting said upper and lower portions and said leading and trailing ends, said leading end having a shape that is asymmetrical from side to side, said trailing end having a shape from side to side different than the shape of said leading end, said interior side adapted to be oriented toward an interior side of another implant when inserted within the disc space, said upper and lower portions being non-arcuate from side to side; and

said implant being manufactured from a bone composite material, said interior side of said implant including a recess so that when said implant is placed side by side another implant having an interior side including a recess a passage is formed adapted to hold bone growth promoting material for permitting for the growth of bone from vertebral body to vertebral body through said passage; and

the combined width of said pair of said implants being greater than one half the width of the adjacent vertebral bodies into which said implants are adapted to be inserted.

90. The implant of claim 89, wherein said bone composite material includes at least one of cortical bone fibers, bone filaments, bone particles and bone dust.

91. The implant of claim 89, further comprising a binding material.

92. The implant of claim 91, wherein said binding material is at least one of bioactive and bioresorbable.

93. The implant of claim 89, wherein said leading end includes a generally straight portion from side to side.

94. The implant of claim 93, wherein said straight portion of said leading end is generally oriented at 90 degrees to the mid-longitudinal axis of said implant.

95. The implant of claim 89, wherein at least a portion of said leading end has a reduced height to facilitate insertion of said implant between the two adjacent vertebral bodies.

96. The implant of claim 89, wherein said trailing end is at least in part straight from side to side.

97. The implant of claim 89, wherein said trailing end is configured in the shape of a half circle from side to side.

98. The implant of claim 89, wherein said trailing end is asymmetrical side to side.

99. The implant of claim 89, wherein the trailing end is adapted to conform from side to side to at least a portion of the peripheral contour of at least one of the anterior and posterior aspects of the vertebral bodies adjacent a disc space into which said implant is inserted.

100. The implant of claim 89, wherein said at least one of said interior and exterior sides is at least in part straight.

101. The implant of claim 89, wherein at least one of said interior and exterior sides is at least in part oriented generally parallel to the mid-longitudinal axis of said implant.

102. The implant of claim 89, wherein said interior and exterior sides are at least in part generally parallel one another.

103. The implant of claim 89, wherein at least a portion of said upper and lower surfaces are in an angular relationship to each other from trailing end to leading end for allowing angulation of the adjacent vertebral bodies relative to each other.

104. The implant of claim 89, wherein said upper and lower surfaces include at least one opening in communication with one another to permit for the growth of bone from vertebral body to vertebral body through said implant.

105. The implant of claim 89, wherein said implant has a maximum length less than and approximating the posterior to anterior depth of the vertebral bodies.

106. The implant of claim 89, further comprising a bone engaging surface formed on the exterior of at least said upper and lower portions for engaging the adjacent vertebral bodies, said bone engaging surface including at least one of a protrusion, a ratchet, a spike, a spline, surface roughenings, and knurling.

107. The implant of claim 89, wherein said implant comprises at least in part of a bone growth promoting material.

108. The implant of claim 107, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

109. The implant of claim 89, in combination with a bone growth promoting material.

110. The implant of claim 109, wherein said bone growth promoting material is selected from one of bone, bone derived products, demineralized bone matrix, mineralizing proteins, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.

111. The implant of claim 89, wherein said implant is treated with a bone growth promoting substance.

112. The implant of claim 89, wherein said implant is at least in part resorbable.

113. The implant of claim 89, in combination with a chemical substance adapted to inhibit scar formation.

114. The implant of claim 89, in combination with an antimicrobial material.

115. The implant of claim 89, wherein at least a portion of said implant is treated to promote bone ingrowth between said implant and said adjacent vertebral bodies.

116. The implant of claim 89, further in combination with at least one spinal fixation implant.

117. The implant of claim 89, wherein said trailing end is curved from side to side along a majority of the width of said implant.

118. The implant of claim 89, wherein said implant has a maximum length greater than the maximum width of said implant.

119. The implant of claim 106, wherein said bone engaging surface includes a plurality of ratchets, said ratchets being at least in part forward-facing.

120. The implant of claim 89, wherein said implant has a horizontal mid-longitudinal plane, each of said upper and lower surfaces being in angular relationship relative to the horizontal mid-longitudinal plane of said implant to allow for angulation of the adjacent vertebral bodies relative to each other.

121. The implant of claim 89, wherein said implant includes at least 40 percent of the bone ring from which it is being formed.

122. The implant of claim 89, wherein each of said leading end and said trailing end is at least in part curved from side to side, the curve of said leading end having a radius of curvature different than the radius of curvature of said trailing end.