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US4759766A
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Intervertebral disc endoprosthesis
Assignee: DERR BERN
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Filing: 1987-09-09
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Granted: 1988-07-26
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Expires: 2007-09-09
Abstract
Abstract An intervertebral disc endoprothesis comprises two symmetrical, concave end plates with an intermediate convex spacing piece. The end plates and the spacing piece have a plane guide rim. The end plates either have an edge shoulder or an annular groove for a toroid provided on the spacing piece. Alternatively, the intervertebral disc endoprothesis comprises two asymmetric end plates and a spacing piece, however, the two areas of movement are offset by 90° in relation to each other and are partial surfaces of a cylinder. In the third variation, the two symmetrical end plates are convex, the spacing piece is cylindrical as well as concave at the two ends and has a durable cover.
Inventors
- 👤 Karin Buettner-Janz
- 👤 Bernd Derr
- 👤 Klaus-Peter Erkel
- 👤 Hans-Joachim Helisch
- 👤 Kurt Schellnack
- 👤 Roland Schumann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:06
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/44; A61F2/442; A61F2/4425; A61F2/30721; A61F2/30724; A61F2002/30001; A61F2002/30003; A61F2002/3006; A61F2002/3008; A61F2002/30316; A61F2002/30329; A61F2002/30383; A61F2002/3039; A61F2002/30398; A61F2002/304; A61F2002/30535; A61F2002/30604; A61F2002/30621; A61F2002/30639; A61F2002/30642; A61F2002/30649; A61F2002/30663; A61F2/30767; A61F2/30771; A61F2002/30841; A61F2002/30878; A61F2002/30891; A61F2002/30892; A61F2002/30894; A61F2002/443; A61F2220/00; A61F2220/0025; A61F2250/00; A61F2250/0058; A61F2250/0096; A61F2250/0098; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00179
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
136 words
Intervertebral disc endoprosthesis comprising first and second end plates and a spacing piece, said spacing piece having top and bottom surfaces, said first end plate having a first surface adjacent the top surface of said spacing piece and said second end plate having a second surface adjacent the bottom surface of said spacing piece, said top, bottom, first and second surfaces each being partial surfaces of a cylinder, said top surface and said first surface adjacent the top surface being congruent and defining a first cylinder-shaped movement surface and said bototm surface and said second surface adjacent the bototm surface being congruent and defining a second cylinder-shape movement surface, said first and second movement surfaces being rotationally-offset 90° with respect to each other about a central axis passing through said spacing piece and said end plates.
Claim 2
Dependent Claim
136 words
Intervertebral disc endoprosthesis comprising first and second end plates and a spacing piece, said spacing piece having top and bottom surfaces, said first end plate having a first surface adjacent the top surface of said spacing piece and said second end plate having a second surface adjacent the bottom surface of said spacing piece, said top, bottom, first and second surfaces each being partial surfaces of a cylinder, said top surface and said first surface adjacent the top surface being congruent and defining a first cylinder-shaped movement surface and said bototm surface and said second surface adjacent the bototm surface being congruent and defining a second cylinder-shape movement surface, said first and second movement surfaces being rotationally-offset 90° with respect to each other about a central axis passing through said spacing piece and said end plates.
Claim 3
Dependent Claim
36 words
Intervertebral disc endoprothesis according to claim 1 further comprising respective pins cranially and caudally extending from the spacing piece and a recess in each of the end plates each receiving a respective one of the pins.
References Cited (Backward Citations)
DE3023353A1
Cited
US4401112A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-26 | 1992-01-25 | 1992-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-26 | 1996-01-25 | 1996-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-26 | 2000-01-25 | 2000-07-26 | $7700.00 | Window Closed / Lapsed |