US5824093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prosthetic spinal disc nucleus
Assignee: RayMedica LLC
•
Filing: 1997-06-06
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Granted: 1998-10-20
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Expires: 2017-06-06
Abstract
Abstract An elongated, capsule shaped prosthetic spinal disc nucleus body for implantation into a human inter vertebral spinal disc, made of a hydrogel core and a constraining jacket surrounding the hydrogel core that permits the hydrogel core to deform and reform. The constraining jacket is configured to allow the hydrogel core to hydrate to a predetermined volume and will deform and reform in a desired fashion in response to various loads placed upon the spinal tract. The prosthetic spinal disc nucleus assists in restoring the natural physiology of the human intervertebral disc. By implanting two prosthetic spinal disc nuclei side-by-side into a damaged disc of a human spine, both height and motion can be maintained.
Inventors
- 👤 Charles D. Ray
- 👤 Eugene A. Dickhudt
- 👤 Robert L. Assell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:26
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/44; A61F2/441; A61F2/3094; A61F2/30965; A61F2/442; A61F2002/30001; A61F2002/30003; A61F2002/3006; A61F2002/3008; A61F2002/30108; A61F2002/3011; A61F2002/30138; A61F2002/30156; A61F2002/30199; A61F2002/30224; A61F2002/30235; A61F2002/30291; A61F2002/30293; A61F2002/30316; A61F2002/30329; A61F2002/30461; A61F2002/30535; A61F2002/30579; A61F2002/30617; A61F2/30767; A61F2/30771; A61F2002/30841; A61F2002/30878; A61F2002/444; A61F2002/448; A61F2002/4495; A61F2220/00; A61F2220/0025; A61F2220/0075; A61F2230/00; A61F2230/0002; A61F2230/0017; A61F2230/0023; A61F2230/0063; A61F2230/0069; A61F2230/0091; A61F2250/00; A61F2250/0058; A61F2250/0096; A61F2250/0097; A61F2250/0098
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
107 words
A prosthetic spinal disc nucleus for implantation into a human disc space having a nucleus region defined by an anulus and adjacent vertebral end plates, the prosthetic spinal disc nucleus comprising: a hydrogel core having an oval-shaped frontal cross-section defining a major axis and a minor axis, wherein the hydrogel core is configured to expand from a dehydrated state to a hydrated state; and a constraining jacket surrounding the hydrogel core, wherein the constraining jacket maintains the hydrogel core in the hydrated state at a major axis diameter in the range of approximately 10-20 millimeters and a minor axis diameter in the range of approximately 5-15 millimeters.
Claim 2
Dependent Claim
107 words
A prosthetic spinal disc nucleus for implantation into a human disc space having a nucleus region defined by an anulus and adjacent vertebral end plates, the prosthetic spinal disc nucleus comprising: a hydrogel core having an oval-shaped frontal cross-section defining a major axis and a minor axis, wherein the hydrogel core is configured to expand from a dehydrated state to a hydrated state; and a constraining jacket surrounding the hydrogel core, wherein the constraining jacket maintains the hydrogel core in the hydrated state at a major axis diameter in the range of approximately 10-20 millimeters and a minor axis diameter in the range of approximately 5-15 millimeters.
Claim 3
Dependent Claim
24 words
The prosthetic spinal disc nucleus of claim 1 wherein the constraining jacket has a textured outer surface for providing purchase within the disc space.
Claim 4
Dependent Claim
29 words
The prosthetic spinal disc nucleus of claim 1 wherein the constraining jacket maintains the hydrogel core at a length in the range of approximately 10-30millimeters in the hydrated state.
Claim 5
Dependent Claim
24 words
The prosthetic spinal disc nucleus of claim 1 wherein the major axis diameter of the hydrogel core is 15 millimeters in the hydrated state.
Claim 6
Dependent Claim
24 words
The prosthetic spinal disc nucleus of claim 1 wherein the minor axis diameter of the hydrogel core is 10 millimeters in the hydrated state.
Claim 7
Dependent Claim
28 words
The prosthetic spinal disc nucleus of claim 1 wherein the constraining jacket has a volume which is less than the volume of the hydrogel core when completely hydrated.
Claim 8
Dependent Claim
26 words
The prosthetic spinal disc nucleus of claim 1 wherein the hydrogel core is configured to have a predetermined compression modulus of elasticity in the hydrated state.
Claim 9
Dependent Claim
70 words
The prosthetic spinal disc nucleus of claim 1 wherein the nucleus region has a loaded volume when a load is placed upon the disc space and an unloaded volume when the load is decreased, the loaded volume being less than the unloaded volume, and further wherein the hydrogel core is configured to force fluid from the nucleus region after implantation in response to the load placed upon the disc space.
Claim 10
Dependent Claim
45 words
The prosthetic spinal disc nucleus of claim 8 wherein the hydrogel core occupies a first percentage of the loaded volume of the nucleus region and a second percentage of the unloaded volume of the nucleus region, the second percentage being less than the first percentage.
Claim 11
Dependent Claim
52 words
The prosthetic spinal disc nucleus of claim 1 wherein the hydrogel core has a predetermined frontal cross-sectional area in the hydrated state, and further wherein the hydrogel core is configured such that following implant, the predetermined frontal cross-sectional area will not change in response to a load placed upon the disc space.
Claim 12
Dependent Claim
54 words
The prosthetic spinal disc nucleus of claim 1 wherein the hydrogel core is configured to have a predetermined shape in the hydrated state, and further wherein the hydrogel core is configured to deform in response to a load placed upon the disc space and reform to the predetermined shape after removal of the load.
Claim 13
Dependent Claim
31 words
The prosthetic spinal disc nucleus of claim 1 wherein the jacket is substantially inelastic and has a fixed circumference for directing the hydrogel core to expand in the minor axis diameter.
Claim 14
Dependent Claim
95 words
A prosthetic spinal disc nucleus for implantation into a human disc space having a nucleus region defined by an anulus and adjacent vertebral end plates, the prosthetic spinal disc nucleus comprising: a hydrogel core having an oval-shaped frontal cross-section defining a major axis and a minor axis, wherein the hydrogel core is configured to deform from an unloaded state to a loaded state; and a constraining jacket surrounding the hydrogel core, wherein the constraining jacket maintains the hydrogel core in the loaded state at a minor axis diameter in the range of approximately 3-10 millimeters.
Claim 15
Dependent Claim
95 words
A prosthetic spinal disc nucleus for implantation into a human disc space having a nucleus region defined by an anulus and adjacent vertebral end plates, the prosthetic spinal disc nucleus comprising: a hydrogel core having an oval-shaped frontal cross-section defining a major axis and a minor axis, wherein the hydrogel core is configured to deform from an unloaded state to a loaded state; and a constraining jacket surrounding the hydrogel core, wherein the constraining jacket maintains the hydrogel core in the loaded state at a minor axis diameter in the range of approximately 3-10 millimeters.
Claim 16
Dependent Claim
154 words
An incompressible, elastic, deformable and reformable spinal disc nucleus prosthesis, including a core surrounded by a jacket, implanted within a nucleus cavity having a variable volume defined by an anulus and a pair of spaced vertebral end plates, the prosthesis having a fixed volume following completion of implantation that is less than the volume of the nucleus cavity, a height which decreases with increasing load on the end plates and which increases with decreasing load on the end plates to allow for corresponding variation in volume of the nucleus cavity so that when the volume of the nucleus cavity decreases with increasing load on the end plates, a pressure within the nucleus cavity is increased to force fluid out of the nucleus cavity, and when the volume of the nucleus cavity increases with decreasing load on the end plates, the pressure within the nucleus cavity is decreased to draw fluid into the nucleus cavity.
Claim 17
Dependent Claim
154 words
An incompressible, elastic, deformable and reformable spinal disc nucleus prosthesis, including a core surrounded by a jacket, implanted within a nucleus cavity having a variable volume defined by an anulus and a pair of spaced vertebral end plates, the prosthesis having a fixed volume following completion of implantation that is less than the volume of the nucleus cavity, a height which decreases with increasing load on the end plates and which increases with decreasing load on the end plates to allow for corresponding variation in volume of the nucleus cavity so that when the volume of the nucleus cavity decreases with increasing load on the end plates, a pressure within the nucleus cavity is increased to force fluid out of the nucleus cavity, and when the volume of the nucleus cavity increases with decreasing load on the end plates, the pressure within the nucleus cavity is decreased to draw fluid into the nucleus cavity.
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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) | 2001-10-19 | 2002-04-20 | 2002-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-19 | 2006-04-20 | 2006-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-19 | 2010-04-20 | 2010-10-20 | $7700.00 | Window Closed / Lapsed |