US4280233A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bone connective prosthesis comprising a reinforcement element carrying a polymer layer having a varying modulus of elasticity
Assignee: SIRDAN RESEARCH Ltd Inc
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Filing: 1979-08-03
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Granted: 1981-07-28
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Expires: 1999-08-03
Abstract
Abstract Improved bone connective prostheses are disclosed. The prostheses comprise a reinforcement element carrying a polymer layer having a varying modulus of elasticity. The exterior surface of the polymer layer constitutes the bone attachment surface of the prostheses and has the lowest modulus of elasticity. The interior surface of the polymer layer is attached to reinforcement element and has the highest modulus of elasticity. Portions of the polymer layer lying between the exterior and the interior surface of the polymer layer have moduli of elasticity which are intermediate with respect to the moduli of elasticity of the exterior and interior surface of the layer. The modulus of elasticity of the layer decreases in the direction of interior to exterior. The decrease in modulus of elasticity may be either continuous or incremental. The reinforcement element may have either a simple or a complex structure.
Inventors
- 👤 Simon Raab
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:07
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/3094; A61F2/30965; A61F2/30767; A61F2/32; A61F2/36; A61F2/3601; A61F2/3603; A61F2/38; A61F2/389; A61L; A61L27/00; A61L27/28; A61L27/34; A61F2/34; A61F2/3662; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30011; A61F2002/30014; A61F2002/30906; A61F2002/30925; A61F2002/30929; A61F2/3609; A61F2002/3625; A61F2002/3631; A61F2/46; A61F2002/4631; A61F2250/00; A61F2250/0014; A61F2250/0018; A61F2250/0023; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00017; A61F2310/00023; A61F2310/00029; A61F2310/00389; A61F2310/00952; Y; Y10; Y10S; Y10S623/00; Y10S623/92; Y10S623/923; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24595; Y10T428/24942; Y10T428/24992; Y10T428/249921; Y10T428/249953; Y10T428/249955
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
191 words
A prosthesis adapted to be fixedly attached to bone by means of bone cement, said prosthesis comprising a reinforcement element, at least a portion of the surface of said reinforcement element carrying a polymer layer having substantial thickness, the exterior surface of said polymer layer constituting the bone attachment surface of said prosthesis, the interior surface of said polymer layer being secured to said reinforcement element, said polymer layer having a varying modulus of elasticity such that the modulus of elasticity of portions of said layer adjacent said interior surface is essentially constant and the modulus of elasticity of portions adjacent said exterior surface is essentially constant, said modulus of elasticity of said portions adjacent said interior surface being greater than said modullus of elasticity of said portions adjacent said exterior surface, portions of said layer which are between said portions adjacent said exterior surface and said portions adjacent said interior surface having a modulus of elasticity which is intermediate with respect to the moduli of said portions adjacent said exterior and interior surfaces and wherein the modulus of elasticity of said layer decreases in the direction of interior to exterior.
Claim 2
Dependent Claim
191 words
A prosthesis adapted to be fixedly attached to bone by means of bone cement, said prosthesis comprising a reinforcement element, at least a portion of the surface of said reinforcement element carrying a polymer layer having substantial thickness, the exterior surface of said polymer layer constituting the bone attachment surface of said prosthesis, the interior surface of said polymer layer being secured to said reinforcement element, said polymer layer having a varying modulus of elasticity such that the modulus of elasticity of portions of said layer adjacent said interior surface is essentially constant and the modulus of elasticity of portions adjacent said exterior surface is essentially constant, said modulus of elasticity of said portions adjacent said interior surface being greater than said modullus of elasticity of said portions adjacent said exterior surface, portions of said layer which are between said portions adjacent said exterior surface and said portions adjacent said interior surface having a modulus of elasticity which is intermediate with respect to the moduli of said portions adjacent said exterior and interior surfaces and wherein the modulus of elasticity of said layer decreases in the direction of interior to exterior.
Claim 3
Dependent Claim
34 words
A prosthesis in accordance with claim 1 wherein the modulus of elasticity of said portions of said layer adjacent said exterior surface is approximately equal to the modulus of elasticity of hardened bone cement.
Claim 4
Dependent Claim
34 words
A prosthesis in accordance with claim 2 wherein the modulus of elasticity of said portions of said layer adjacent said interior surface is approximately equal to the modulus of elasticity of said reinforcement element.
Claim 5
Dependent Claim
24 words
A prosthesis in accordance with claim 1 wherein said modulus of elasticity of said layer decreases continuously in the direction of interior to exterior.
Claim 6
Dependent Claim
74 words
A prosthesis in accordance with claim 4 wherein said polymer layer comprises voids, said voids being distributed throughout said polymer layer such that the percentage of volume occupied by voids in portions of said layer adjacent said exterior surface is greater than the percentage of volume occupied by voids in portions of said layer adjacent said interior surface, said void volume percentage continuously increasing in the direction of interior to exterior of said layer.
Claim 7
Dependent Claim
28 words
A prosthesis in accordance with claim 5 wherein the percentage of volume occupied by voids in said portions of said layer adjacent said interior surface is about zero.
Claim 8
Dependent Claim
15 words
A prosthesis in accordance with claim 5 wherein said reinforcement element consists essentially of metal.
Claim 9
Dependent Claim
19 words
A prosthesis in accordance with claim 7 wherein said polymer layer has a thickness of greater tha 0.10 cm.
Claim 10
Dependent Claim
15 words
A prosthesis in accordance with claim 8 wherein said prosthesis is a stem insertion prosthesis.
Claim 11
Dependent Claim
25 words
A prosthesis in accordance with claim 1 wherein said modulus of elasticity of said polymer layer decreases incrementally in the direction of interior to exterior.
Claim 12
Dependent Claim
25 words
A prosthesis in accordance with claim 10 wherein said polymer layer is a composite of discrete polymer layers each having a different modulus of elasticity.
Claim 13
Dependent Claim
21 words
A prosthesis in accordance with claim 11 wherein each of said discrete polymer layers comprises a different amount of a plasticizer.
Claim 14
Dependent Claim
24 words
A prosthesis in accordance with claim 12 wherein each of said layers has a greater amount of plasticizer than the adjacent, more interior layer.
Claim 15
Dependent Claim
21 words
A prosthesis in accordance with claim 11 wherein each of said discrete layers comprises a different amount of a reinforcement filler.
Claim 16
Dependent Claim
15 words
A prosthesis in accordance with claim 14 wherein said reinforcement filler is a particulate material.
Claim 17
Dependent Claim
15 words
A prosthesis in accordance with claim 14 wherein said reinforcement filler is a fiberous material.
Claim 18
Dependent Claim
25 words
A prosthesis in accordance with claim 14 wherein each of said layers has a lesser amount of reinforcement filler than the adjacent, more interior layer.
Claim 19
Dependent Claim
29 words
A prosthesis in accordance with claim 1 wherein said reinforcement element has an irregular shape and wherein the external surface of said polymer layer has a simple, regular shape.
Claim 20
Dependent Claim
16 words
A prosthesis in accordance with claim 18 wherein said reinforcement element is composed of a metal.
Claim 21
Dependent Claim
15 words
A prosthesis in accordance with claim 18 wherein said prosthesis is a stem insertion prosthesis.
Claim 22
Dependent Claim
15 words
A prosthesis in accordance with claim 19 wherein said prosthesis is a stem insertion prosthesis.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-07-27 | 1985-01-26 | 1985-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-27 | 1989-01-26 | 1989-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-27 | 1993-01-26 | 1993-07-28 | $7700.00 | Window Closed / Lapsed |