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US5888227A Expired / Lapsed US ⏱️ 0.0 years remaining

Inter-vertebral implant

Assignee: Synthes USA LLC
•
Filing: 1996-10-03
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Granted: 1999-03-30
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Expires: 2016-10-03
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Abstract

Abstract An inter-vertebral implant having of a frame-like cage (1) enclosing a space (20), with a top and bottom surface (11,12), two side surfaces (13, 14), a front (16) and a rear wall (15). The top and bottom surfaces (11, 12) have a plurality of perforations (24), the total area of which amounts to 40 to 55% of the total area of said surfaces (11, 12). The individual area of a single perforation (24) is at most 20% of the total area of the top and bottom surfaces (11, 12). The ratio VH/VK between the volume VH of the space (20) and the total volume VK of the cage (1) is in the range from 70 to 90%. The cage (1) is substantially wedge-shaped with top and bottom surfaces (11, 12) diverging towards the front wall (16). This gives the advantage that, owing to the large bone bearing area of the top and bottom surfaces, the implant is prevented from sinking into the end plates of the body of the vertebra.

Inventors

  • 👤 William Cottle

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 05:14
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/44; A61F2/4455; A61F2/442; A61F2/46; A61F2/4603; A61F2/4611; A61F2/28; A61F2002/2835; A61F2002/30001; A61F2002/30108; A61F2002/3011; A61F2002/30112; A61F2002/30138; A61F2002/30158; A61F2002/30199; A61F2002/30261; A61F2002/30266; A61F2002/30316; A61F2002/30535; A61F2002/30593; A61F2/30767; A61F2/30771; A61F2002/30772; A61F2002/30777; A61F2002/30784; A61F2002/30785; A61F2002/30795; A61F2002/308; A61F2002/3082; A61F2002/30841; A61F2002/30843; A61F2002/30878; A61F2002/30891; A61F2002/30892; A61F2230/00; A61F2230/0002; A61F2230/0004; A61F2230/0017; A61F2230/0026; A61F2230/0063; A61F2230/0082; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00023; A61F2310/00179

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 126 words
An intervertebral implant comprising a frame-like cage which is essentially wedge-shaped, encloses a cavity, and which has perforated cover and base faces as bone-contacting surfaces, two lateral surfaces, and front and rear walls, wherein the cover and base faces diverge toward the front wall, and at least one of the cover face or base face has a plurality of perforations whose total area makes up 40 to 50% of the total area of the cover face or base face; with each individual perforation having an area amounting at most to 20% of the total area of the cover face or base face; and wherein the cavity has a volume VH, the cage has a volume VK, and the ratio of VH/VK is from 0.11 to 0.42.
Claim 2
Dependent Claim 126 words
An intervertebral implant comprising a frame-like cage which is essentially wedge-shaped, encloses a cavity, and which has perforated cover and base faces as bone-contacting surfaces, two lateral surfaces, and front and rear walls, wherein the cover and base faces diverge toward the front wall, and at least one of the cover face or base face has a plurality of perforations whose total area makes up 40 to 50% of the total area of the cover face or base face; with each individual perforation having an area amounting at most to 20% of the total area of the cover face or base face; and wherein the cavity has a volume VH, the cage has a volume VK, and the ratio of VH/VK is from 0.11 to 0.42.
Claim 3
Dependent Claim 18 words
The implant of claim 1, wherein the cover and the base faces are provided with a three-dimensional structure.
Claim 4
Dependent Claim 53 words
The implant of claim 1, wherein the cover and base faces each include a central region surrounded by an edge region, and the perforations affixed to the edge region of the cover or base face, on average, are smaller than the perforations affixed to the central region of the cover or base face.
Claim 5
Dependent Claim 16 words
The implant of claim 1, wherein the cover and base faces are configured to bulge outward.
Claim 6
Dependent Claim 15 words
The implant of claim 1, wherein the perforations have a maximum diameter of 9 mm.
Claim 7
Dependent Claim 26 words
The implant of claim 1, wherein the lateral faces have perforations whose total area is at most 40% of the total area of the lateral faces.
Claim 8
Dependent Claim 28 words
The implant of claim 6, wherein the lateral faces (13, 14) have perforations whose total area is at least 15% of the total area of the lateral faces.
Claim 9
Dependent Claim 14 words
The implant of claim 2, wherein the three-dimensional structure is a structured hydroxyl-apatite coating.
Claim 10
Dependent Claim 19 words
The implant of claim 2, wherein the three-dimensional structure is a structured coating of titanium or a titanium alloy.
Claim 11
Dependent Claim 15 words
The implant of claim 2, wherein the three-dimensional structure comprises a regular arrangement of teeth.
Claim 12
Dependent Claim 15 words
The implant of claim 2, wherein the three-dimensional structure has a height of 0.5-2.0 mm.
Claim 13
Dependent Claim 19 words
The implant of claim 1, wherein the front wall has means to receive an instrument for manipulating the cage.
Claim 14
Dependent Claim 19 words
The implant of claim 1, wherein each lateral face has means to receive an instrument for manipulating the cage.
Claim 15
Dependent Claim 24 words
The implant of claim 1, wherein the cover face and the base face each has an edge which is free of three dimensional structure.
Claim 16
Dependent Claim 15 words
The implant of claim 1, wherein the perforations in the lateral faces are longitudinal holes.
Claim 17
Dependent Claim 19 words
The implant of claim 1; wherein the front wall is equipped with perforations in the form of longitudinal holes.
Claim 18
Dependent Claim 12 words
The implant of claim 1, wherein the cage is coated with hydroxylapatite.
Claim 19
Dependent Claim 25 words
The implant of claim 1, wherein each individual perforation has an area which constitutes 5-15% of the total area of the cover or base face.
Claim 20
Dependent Claim 15 words
The implant of claim 1, wherein the ratio of VH/VK ranges between 0.17 and 0.33.
Claim 21
Dependent Claim 21 words
The implant of claim 1, wherein the total area of the perforations in the cover or base face amount to 43-51%.
Claim 22
Dependent Claim 25 words
A combination implant with two intervertebral implants in accordance with claim 1, wherein the two intervertebral implants are joined integrally together at their lateral faces.
Claim 23
Dependent Claim 17 words
The combination of implant of claim 21, wherein the combined front wall has a longitudinal hole recess.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-03-29 2002-09-28 2003-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-03-29 2006-09-28 2007-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-03-29 2010-09-28 2011-03-30 $7700.00 Window Closed / Lapsed

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