Patent US3537605A successfully refreshed from Google Patents.
Patent US5171281A successfully refreshed from Google Patents.
US5171281A
Expired / Lapsed
US
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Functional and biocompatible intervertebral disc spacer containing elastomeric material of varying hardness
Assignee: Rutgers Health
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Filing: 1991-10-09
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Granted: 1992-12-15
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Expires: 2011-10-09
Abstract
Abstract The construction and manufacturing technique for a functional biocompatible intervertebral disc spacer is described. This device is useful for a replacement for a degenerated disc in certain treatments of back pain and spinal disease. The disc spacer possesses mechanical properties skin to those of the normal disc and will preserve normal functions of the spinal motion segment. The device achieves the desired properties by varying the hardness of the elastomeric material in its nucleus and annulus.
Inventors
- 👤 John R. Parsons
- 👤 Casey K. Lee
- 👤 Noshir A. Langrana
- 👤 Alastair J. Clemow
- 👤 Elizabeth H. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:11
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/44; A61F2/442; A61F2/30721; A61F2/30724; A61F2/30767; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30016; A61F2002/3006; A61F2002/30065; A61F2002/30069; A61F2002/30108; A61F2002/3011; A61F2002/30112; A61F2002/30133; A61F2002/30316; A61F2002/30535; A61F2002/30563; A61F2/3094; A61F2002/30968; A61F2210/00; A61F2210/0071; A61F2230/00; A61F2230/0002; A61F2230/0004; A61F2230/0015; A61F2250/00; A61F2250/0014; A61F2250/0019; A61F2310/00; A61F2310/00389; A61F2310/00395; A61F2310/00407; A61F2310/00592; A61F2310/00796; A61F2310/00952
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
122 words
A biocompatible intervertebral spacer comprising: a central core of an unreinforced soft biocompatible elastomeric material shaped and sized so as to approximate the shape and size of a nucleus pulposus of a natural intervertebral disc; an outer ring of stiff unreinforced elastomeric material surrounding said central core to approximate the size and shape of a natural annulus fibrous, said outer ring and said central core forming a disc having upper and lower surfaces; and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material; said spacer having a mean torsional stiffness of from 0.8 Nm/degree to 3.0 Nm/degree and a mean axial stiffness of from 1000 newtons/mm to about 3000 newtons/mm.
Claim 2
Dependent Claim
122 words
A biocompatible intervertebral spacer comprising: a central core of an unreinforced soft biocompatible elastomeric material shaped and sized so as to approximate the shape and size of a nucleus pulposus of a natural intervertebral disc; an outer ring of stiff unreinforced elastomeric material surrounding said central core to approximate the size and shape of a natural annulus fibrous, said outer ring and said central core forming a disc having upper and lower surfaces; and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material; said spacer having a mean torsional stiffness of from 0.8 Nm/degree to 3.0 Nm/degree and a mean axial stiffness of from 1000 newtons/mm to about 3000 newtons/mm.
Claim 3
Dependent Claim
15 words
A spacer according to claim 1 wherein the biocompatible elastomer is a thermoplastic polyurethane elastomer.
Claim 4
Dependent Claim
17 words
A spacer according to claim 1 wherein the biocompatible elastomer is a polysiloxane modified styrene-ethylene/butylene block copolymer.
Claim 5
Dependent Claim
11 words
A spacer according to claim 1 wherein the endplates contain hydroxylapatite.
Claim 6
Dependent Claim
24 words
A spacer according to claim 1 wherein the outer ring surrounding said central core contains 1-5 layers of a biocompatible elastomer of varying hardness.
Claim 7
Dependent Claim
15 words
A spacer according to claim 5 wherein the biocompatible elastomer is a thermoplastic polyurethane elastomer.
Claim 8
Dependent Claim
17 words
A spacer according to claim 5 wherein the biocompatible elastomer is a polysiloxane modified styrene-ethylene/butylene block copolymer.
Claim 9
Dependent Claim
11 words
A spacer according to claim 5 wherein the endplates contain hydroxylapatite.
Claim 10
Dependent Claim
24 words
A spacer according to claim 1 wherein the outer ring surrounding said central core contains 2-3 layers of a biocompatible elastomer of varying hardness.
Claim 11
Dependent Claim
15 words
A spacer according to claim 9 wherein the biocompatible elastomer is a thermoplastic polyurethane elastomer.
Claim 12
Dependent Claim
17 words
A spacer according to claim 9 wherein the biocompatible elastomer is a polysiloxane modified styrene-ethylene/butylene block copolymer.
Claim 13
Dependent Claim
11 words
A spacer according to claim 9 wherein the endplates contain hydroxylapatite.
Claim 14
Dependent Claim
21 words
A spacer according to claim 1 wherein the central core contains 1-5 layers of a biocompatible elastomeric material of varying hardness.
Claim 15
Dependent Claim
15 words
A spacer according to claim 13 wherein the biocompatible elastomer is a thermoplastic polyurethane elastomer.
Claim 16
Dependent Claim
17 words
A spacer according to claim 13 wherein the biocompatible elastomer is a polysiloxane modified styrene-ethylene/butylene block copolymer.
Claim 17
Dependent Claim
11 words
A spacer according to claim 13 wherein the endplates contain hydroxylapatite.
Claim 18
Dependent Claim
11 words
A spacer according to claim 1 wherein the endplates are metal.
Claim 19
Dependent Claim
17 words
A spacer according to claim 1 wherein the endplates have a porous metallic or polymeric sintered surface.
Claim 20
Dependent Claim
26 words
A spacer according to claim 1 wherein the endplates are further comprised of a means for mechanically interlocking with adjacent vertebrae during surgical implantation or use.
Claim 21
Dependent Claim
35 words
A spacer according to claim 1 wherein the end plates are provided with a roughened surface opposite the affixed surface thereby facilitating cementing the end plates to adjacent natural bone surfaces with polymethylmethacrylate bone cement.
Claim 22
Independent Claim
147 words
A method of alleviating pain or paralysis caused by a damaged or diseased intervebral disc which comprises replacing all or part of the damaged or diseased disc with a biocompatible intervertebral spacer, said spacer comprising: a central core of an unreinforced soft biocompatible elastomeric material shaped and sized so as to approximate the shape and size of a natural intervertebral disc; an outer ring of stiff unreinforced elastomeric material surrounding said central core and approximating the size and shape of a natural annulus fibrousus, said outer ring and said central core forming a disc having upper and lower surface; and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material; said spacer having a mean torsional stiffness of from 0.8 Nm/degree to 3.0 Nm/degree and a mean axial stiffness of from 1000 newtons/mm to 3500 newtons/mm.
Claim 23
Independent Claim
147 words
A method of alleviating pain or paralysis caused by a damaged or diseased intervebral disc which comprises replacing all or part of the damaged or diseased disc with a biocompatible intervertebral spacer, said spacer comprising: a central core of an unreinforced soft biocompatible elastomeric material shaped and sized so as to approximate the shape and size of a natural intervertebral disc; an outer ring of stiff unreinforced elastomeric material surrounding said central core and approximating the size and shape of a natural annulus fibrousus, said outer ring and said central core forming a disc having upper and lower surface; and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material; said spacer having a mean torsional stiffness of from 0.8 Nm/degree to 3.0 Nm/degree and a mean axial stiffness of from 1000 newtons/mm to 3500 newtons/mm.
Claim 24
Dependent Claim
23 words
A method according to claim 21 wherein the core/outer ring of the disc spacer are comprised of a polysiloxane modified styrene-ethylene/butylene block copolymer.
Claim 25
Dependent Claim
12 words
A method according to claim 21 wherein the spacer contains metal endplates.
Claim 26
Dependent Claim
14 words
A method according to claim 21 wherein the spacer contains endplates of elastomeric material.
Claim 27
Dependent Claim
11 words
A method according to claim 21 wherein the endplates contain hydroxylapatite.
Claim 28
Dependent Claim
30 words
A spacer according to claim 21 wherein said mean torsional stiffness is from 1.0 Nm/degree to 2.0 Nm/degree and said mean axial stiffness is from 2000 newtons/mm to 3000 newtons/mm.
Claim 29
Dependent Claim
121 words
A biocompatible intervertebral disc spacer comprised of: a central core comprised of an unreinforced, soft biocompatible elastomeric material shaped and sized to approximate the size and shape of a nucleus pulposus of a natural intervertebral disc; an outer ring of stiff, unreinforced elastomeric material surrounding said central core which approximates the size and shape of a natural annulus fibrosus, said outer ring and central core forming a disc having upper and lower surfaces, and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material, said spacer having a mean torsional stiffness of from 1.0 Nm/degree to 2.0 Nm/degree and a mean axial stiffness of from 2000 newtons/mm to 3000 newtons/mm.
Claim 30
Dependent Claim
121 words
A biocompatible intervertebral disc spacer comprised of: a central core comprised of an unreinforced, soft biocompatible elastomeric material shaped and sized to approximate the size and shape of a nucleus pulposus of a natural intervertebral disc; an outer ring of stiff, unreinforced elastomeric material surrounding said central core which approximates the size and shape of a natural annulus fibrosus, said outer ring and central core forming a disc having upper and lower surfaces, and endplates comprised of a stiff biocompatible material and affixed to each of said upper and lower surfaces with additional elastomeric material, said spacer having a mean torsional stiffness of from 1.0 Nm/degree to 2.0 Nm/degree and a mean axial stiffness of from 2000 newtons/mm to 3000 newtons/mm.
Claim 31
Dependent Claim
138 words
In an implantable, biocompatible, intervertebral spacer which is comprised of (a) a central core having the softness of a natural nucleus pulposus, (b) an outer ring which angularly surrounds the central core and which is comprised of a biocompatible elastomeric material having the stiffness of a natural annulus fibrosus, said central core and outer ring forming a disc having upper and lower surfaces, and (c) upper and lower endplates affixed to the upper and lower surfaces of the disc respectively, each of such endplate being comprised of a biocompatible, stiff material affixed to the upper and lower surfaces of the disc, the improvement comprising utilizing an unreinforced material as the central core and annular outer ring which provides the spacer with a mean axial stiffness of about 1000-3000 newtons/mm and a mean torsional stiffness of about 0.8-3.0 Nm/degree.
Claim 32
Dependent Claim
138 words
In an implantable, biocompatible, intervertebral spacer which is comprised of (a) a central core having the softness of a natural nucleus pulposus, (b) an outer ring which angularly surrounds the central core and which is comprised of a biocompatible elastomeric material having the stiffness of a natural annulus fibrosus, said central core and outer ring forming a disc having upper and lower surfaces, and (c) upper and lower endplates affixed to the upper and lower surfaces of the disc respectively, each of such endplate being comprised of a biocompatible, stiff material affixed to the upper and lower surfaces of the disc, the improvement comprising utilizing an unreinforced material as the central core and annular outer ring which provides the spacer with a mean axial stiffness of about 1000-3000 newtons/mm and a mean torsional stiffness of about 0.8-3.0 Nm/degree.
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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) | 1995-12-15 | 1996-06-15 | 1996-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-15 | 2000-06-15 | 2000-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-15 | 2004-06-15 | 2004-12-15 | $7700.00 | Window Closed / Lapsed |