Expandable spinal implant having interlocking geometry for structural support

• US 20100121453A1
• Filed: 01/14/2010
• Published: 05/13/2010
• Est. Priority Date: 07/23/2004
• Status: Active Grant

• Current Assignee: Marc Peterman
• Original Assignee: Marc Peterman
• Inventors: Peterman, Marc
• Granted Patent: US 8,303,658 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• 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 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30515 using a locking wedge or block
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/3085 with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30879 Ribs
• 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 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0091 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00359 : Bone or bony tissue

Abstract

An expandable spinal implant including at least two expandable branch portions extending generally along a longitudinal axis and each including a fixed end portion and an opposite movable end portion with the fixed end portions coupled together adjacent a base portion of the implant. A first of the branch portions includes at least one transverse projection having opposite axially-facing outer surfaces. A second of the branch portions defines at least one transverse recess having opposing axially-facing inner surfaces. The transverse projection is positioned within and displacable along the transverse recess with the outer surfaces of the projection positioned in close proximity with the inner surfaces of the recess to provide structural support to the implant subsequent to expansion. In one embodiment, the branch portions are separated from one another by at least one slot including a narrow portion that defines the close fitting transverse projection and transverse recess.

Claims

1-60. -60. (canceled)

61. An expandable spinal implant, comprising:

a body extending generally along a longitudinal axis between a first end portion and a second end portion, said body defining at least one slot extending generally along said longitudinal axis from said first end portion toward said second end portion to provide said body with at least two expandable branch portions coupled together adjacent said second end portion, said body including at least one transverse projection defined by a first of said branch portions and a transverse recess defined by a second of said branch portions, said transverse recess having opposing inner surfaces that engage said transverse projection to provide structural support to the implant subsequent to expansion; and

a retention element extending transversely between and engaged with said at least two branch portions subsequent to expansion of the implant to maintain said body in an expanded configuration.

62. The implant of claim 61, wherein said transverse projection is positioned within and displacable along said transverse recess to provide close fitting interlocking features between said branch portions that provide said structural support to the implant subsequent to expansion.

63. The implant of claim 61, wherein said transverse projection defines oppositely facing outer surfaces positioned in close proximity with respective ones of said inner surfaces of said transverse recess to provide close fitting interlocking features between said branch portions that provide said structural support to the implant subsequent to expansion.

64. The implant of claim 61, wherein said branch portions are pivotally displaced relative to one another about a pivot axis during expansion of the implant, said transverse projection and said transverse recess defining an adjacent pair of surfaces having generally the same radius of curvature relative to said pivot axis.

65. The implant of claim 61, wherein said branch portions are coupled together adjacent said second end portion of said body to allow relative pivotal movement therebetween about a pivot axis, said transverse projection extending generally along a radial arc relative to said pivot axis, said transverse recess also extending generally along said radial arc.

66. The implant of claim 61, wherein said branch portions are coupled together adjacent said second end portion of said body to allow relative pivotal movement therebetween about said pivot axis, said transverse projection having an arcuate outer surface extending generally along a radial arc relative to said pivot axis, said transverse recess having an arcuate inner surface extending generally along said radial arc, said arcuate outer surface of said transverse projection positioned in close proximity with said arcuate inner surface of said transverse recess to provide said structural support to the implant subsequent to expansion.

67. The implant of claim 61, wherein said transverse projection and said transverse recess define a number of said interlocking retention elements configured to maintain the implant in said expanded configuration.

68. The implant of claim 67, wherein said interlocking retention elements comprise interlocking ratchet elements.

69. The implant of claim 61, wherein said second end portion of said body has an outer surface facing away from said branch portions, said outer surface defining a concave curvature to facilitate expansion of the implant.

70. The implant of claim 61, wherein said slot includes an enlarged portion adjacent said second end of said body to facilitate expansion of the implant.

71. The implant of claim 61, wherein said slot has an undulating curved configuration.

72. The implant of claim 61, wherein said branch portions are formed integral with said second end portion of said body to define a single-piece unitary implant body.

73. The implant of claim 61, wherein said branch portions include a pair of opposing notches sized and shaped to interlockingly engage and retain said retention element in a select position upon expansion of the implant.

74. The implant of claim 61, wherein said at least two expandable branch portions cooperate to define a hollow interior of said body;

and

further comprising a bone growth promoting substance disposed within said hollow interior to facilitate fusion with adjacent vertebrae.

75. An expandable spinal implant, comprising:

at least two expandable branch portions extending generally along a longitudinal axis, each of said branch portions including a fixed end portion and an opposite movable end portion with each of said fixed end portions coupled together adjacent a fixed base portion of the implant, a first of said branch portions defining at least one transverse projection and a second of said branch portions defining at least one transverse recess having opposing inner surfaces that engage said transverse projection to provide structural support to the implant subsequent to expansion; and

a retention element extending transversely between and engaged with said at least two branch portions subsequent to expansion of the implant to maintain said body in an expanded configuration.

76. The implant of claim 75, wherein said transverse projection is positioned within and displacable along said transverse recess to provide close fitting interlocking features between said branch portions that provide said structural support to the implant subsequent to expansion.

77. The implant of claim 75, wherein said transverse projection defines oppositely facing outer surfaces positioned in close proximity with respective ones of said inner surfaces of said transverse recess to provide close fitting interlocking features between said branch portions that provide said structural support to the implant subsequent to expansion.

78. The implant of claim 75, wherein said branch portions are coupled together adjacent said second end portion of said body to allow relative pivotal movement therebetween about said pivot axis, said transverse projection having an arcuate outer surface extending generally along a radial arc relative to said pivot axis, said transverse recess having an arcuate inner surface extending generally along said radial arc, said arcuate outer surface of said transverse projection positioned in close proximity with said arcuate inner surface of said transverse recess to provide said structural support to the implant subsequent to expansion.

79. The implant of claim 75, wherein said branch portions are formed integral with said second end portion of said body to define a single-piece unitary implant body.

80. The implant of claim 75, wherein said branch portions include a pair of opposing notches sized and shaped to interlockingly engage and retain said retention element in a select position upon expansion of the implant.