US4778474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acetabular prosthesis
Assignee: TRANQUIL PROSPECTS Ltd A Co OF BRITISH VIRGIN ISLANDS
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Filing: 1985-07-22
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Granted: 1988-10-18
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Expires: 2005-07-22
Abstract
Abstract An improved acetabular prosthesis (14) is disclosed for use with a femoral head prosthesis (12). The acetabular prosthesis (14) comprises a cup (28) having, in use, sufficient strength to maintain its shape. The exterior surface of the cup (28) is substantially hemispherical. A coating (32) of sufficient thickness is provided on the exterior surface of the cup (28). The coating (32) is sufficiently deformable and has limited elastic memory to mold itself to the particular anatomic geometry or inner contour of the acetabulum. The coating (32) has grooves (36) on its external surfaces.
Inventors
- 👤 Charles A. Homsy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:48
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/50; A61L27/56; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/30767; A61F2/32; A61L27/28; A61L27/34; A61F2/34; A61F2/36; A61F2/3662; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30011; A61F2002/30014; A61F2002/3006; A61F2002/30069; A61F2002/3007; A61F2002/30072; A61F2002/30316; A61F2002/30535; A61F2002/30563; A61F2002/30667; A61F2002/30673; A61F2/30771; A61F2002/3082; A61F2002/30827; A61F2002/30929; A61F2/3094; A61F2002/30971; A61F2002/30973; A61F2/3609; A61F2002/3611; A61F2002/3625; A61F2002/3631; A61F2250/00; A61F2250/0014; A61F2250/0018; A61F2250/0023; A61F2310/00; A61F2310/00005; A61F2310/00011
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
221 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and a external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting against said hemispherical ball; and a biocompatible pliant coating over the external convex surface of said cup formed of a deformable porous material having a porosity in the range of 40% to 90% and having interconnecting pores of a size from about 10 to 50 microns for minimizing the ingrowth of tissue into the pores; said coating having a relatively low elastic memory and a relatively low modulus of elasticity generally similar to the cartilage of the acetabulum, said relatively low elastic memory and relatively low modulus of elasticity upon compression and deformation of the coating against the natural cartilage of the acetabulum permitting said coating to mold itself to the inner contour of the cartilage and natural acetabulum for continuously commodating the contour of the acetabulum, said relatively low elastic memory and relatively low modulus of elasticity providing sufficient softness in the coating so that the adjacent cartilage is not abraded or deteriorated therefrom.
Claim 2
Dependent Claim
221 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and a external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting against said hemispherical ball; and a biocompatible pliant coating over the external convex surface of said cup formed of a deformable porous material having a porosity in the range of 40% to 90% and having interconnecting pores of a size from about 10 to 50 microns for minimizing the ingrowth of tissue into the pores; said coating having a relatively low elastic memory and a relatively low modulus of elasticity generally similar to the cartilage of the acetabulum, said relatively low elastic memory and relatively low modulus of elasticity upon compression and deformation of the coating against the natural cartilage of the acetabulum permitting said coating to mold itself to the inner contour of the cartilage and natural acetabulum for continuously commodating the contour of the acetabulum, said relatively low elastic memory and relatively low modulus of elasticity providing sufficient softness in the coating so that the adjacent cartilage is not abraded or deteriorated therefrom.
Claim 3
Dependent Claim
30 words
A prosthesis according to claim 1, characterized in that said cup is made of a material selected from the group consisting of metal, polysulfone polymer, polycarbonate polymer, and polyacetal polymer.
Claim 4
Dependent Claim
27 words
A prosthesis according to claim 1, characterized in that the coating on said cup is porous polytetrafluoroethylene having a porosity in the range from 40% to 90%.
Claim 5
Dependent Claim
17 words
A prosthesis according to claim 3, characterized in that said coating has a porosity of approximately 60%.
Claim 6
Dependent Claim
22 words
A prosthesis according to claim 1, characterized in that said coating has a thickness in the range from 1 to 10 mm.
Claim 7
Dependent Claim
30 words
A prosthesis according to claim 1, characterized in that said coating has a plurality of grooves on its exterior surface to allow, in use, bulk movement of synovial fluid therethrough.
Claim 8
Dependent Claim
20 words
A prosthesis according to claim 3, characterized in that said coating is bonded to said cup with fluorinated ethylene propylene.
Claim 9
Dependent Claim
25 words
A prosthesis according to claim 1, characterized in that a layer of medical grade elastomer lies between the exterior of said cup and said coating.
Claim 10
Dependent Claim
21 words
A prosthesis according to claim 8, characterized in that said layer is mechanically interlocked to said cup and to said coating.
Claim 11
Dependent Claim
19 words
A prosthesis according to claim 8, characterized in that said layer is impregnated into the interior of said coating.
Claim 12
Dependent Claim
16 words
A prosthesis according to claim 8, characterized in that said layer is a medical grade silicone.
Claim 13
Dependent Claim
146 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting in contact with said hemispherical ball; and a biocompatible coating over the external convex surface of said cup formed of a deformable porous material having a relatively low elastic memory and a relatively low modulus of elasticity generally similar to the cartilage of the acetabulum to allow it to mold itself to the inner contour of the natural acetabulum, said coating having pores of a size between about 10 and 50 microns to minimize any tissue ingrowth from said acetabulum.
Claim 14
Dependent Claim
146 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting in contact with said hemispherical ball; and a biocompatible coating over the external convex surface of said cup formed of a deformable porous material having a relatively low elastic memory and a relatively low modulus of elasticity generally similar to the cartilage of the acetabulum to allow it to mold itself to the inner contour of the natural acetabulum, said coating having pores of a size between about 10 and 50 microns to minimize any tissue ingrowth from said acetabulum.
Claim 15
Dependent Claim
26 words
An improved acetabular prosthesis as set forth in claim 12 wherein said coating has an aggregate modulus of elasticity in compression less than around 4 MPa.
Claim 16
Dependent Claim
29 words
An improved acetabular prosthesis as set forth in claim 12 wherein a layer of medical grade elastomer is positioned between said convex surface of the cup and said coating.
Claim 17
Dependent Claim
38 words
An improved acetabular prosthesis as set forth in claim 13 wherein said coating is a porous polytetrafluoroethylene having a porosity in the range from 40% to 90% and a thickness in the range from 1 to 10 mm.
Claim 18
Dependent Claim
166 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in apposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting in contact with said hemispherical ball; a porous biocompatible coating over the external convex surface of said cup formed of a deformable material having a relatively low elastic memory and a modulus of elasticity generally similar to the cartilage of the acetabulum and less than around four megapascals (4 MPa) to allow it to mold itself to the inner contour of the natural acetabulum; and a layer of medical grade elastomer positioned between the exterior of said cup and said coating, said elastomer having a thickness adequate to provide a predetermined resilience for said coating under a predetermined compression thereof.
Claim 19
Dependent Claim
166 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in apposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting in contact with said hemispherical ball; a porous biocompatible coating over the external convex surface of said cup formed of a deformable material having a relatively low elastic memory and a modulus of elasticity generally similar to the cartilage of the acetabulum and less than around four megapascals (4 MPa) to allow it to mold itself to the inner contour of the natural acetabulum; and a layer of medical grade elastomer positioned between the exterior of said cup and said coating, said elastomer having a thickness adequate to provide a predetermined resilience for said coating under a predetermined compression thereof.
Claim 20
Dependent Claim
35 words
An improved acetabular prosthesis as set forth in claim 16 wherein said porous coating has a porosity of between around 40% to 90% and has an internal pore size of around ten to fifty microns.
Claim 21
Dependent Claim
221 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting against said hemispherical ball; and a biocompatible pliant coating over the external convex surface of said cup formed of a deformable porous material having a relatively low elastic memory and a relatively low modulus of elasticity less than around 4 megapascals and generally similar to the cartilage of the acetabulum; said coating having a porosity in the range of 40% to 90% and having interconnecting pores of a size from about 10 to 50 microns for minizing the ingrowth of tissue into the pores, said relatively low elastic memory and relatively low modulus of elasticity upon compression and deformation of the coating against the natural cartilage of the acetabulum permitting said coating to mold itself to the inner contour of the cartilage and natural acetabulum for continuously accommodating the contour of the acetabulum; and means in said coating to permit the flow of synovial fluid into the adjacent cartilage even upon deformation of the coating.
Claim 22
Dependent Claim
221 words
An improved acetabular prosthesis for fitting over a hemispherical ball of a femoral-head prosthesis and adapted to fit within the acetabulum in opposed contacting relation to the natural cartilage of the acetabulum; said prosthesis comprising: a generally rigid cup having an internal concave surface and an external convex surface; a lining over the internal concave surface of said cup formed of a wear-resistant material and fitting against said hemispherical ball; and a biocompatible pliant coating over the external convex surface of said cup formed of a deformable porous material having a relatively low elastic memory and a relatively low modulus of elasticity less than around 4 megapascals and generally similar to the cartilage of the acetabulum; said coating having a porosity in the range of 40% to 90% and having interconnecting pores of a size from about 10 to 50 microns for minizing the ingrowth of tissue into the pores, said relatively low elastic memory and relatively low modulus of elasticity upon compression and deformation of the coating against the natural cartilage of the acetabulum permitting said coating to mold itself to the inner contour of the cartilage and natural acetabulum for continuously accommodating the contour of the acetabulum; and means in said coating to permit the flow of synovial fluid into the adjacent cartilage even upon deformation of the coating.
Claim 23
Dependent Claim
45 words
An improved acetabulum prosthesis as set forth in claim 18 wherein said means in said coating to permit the flow of synovial fluid into the adjacent cartilage even upon deformation of the coating comprises a plurality of grooves on the external surface of the coating.
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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) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-18 | 2000-04-18 | 2000-10-18 | $7700.00 | Window Closed / Lapsed |