EP0356112A1
Expired / Lapsed
EP
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Biocompatible elastomeric intervertebral disc
Assignee: Rutgers, The State University of New Jersey
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Filing: 1989-08-15
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Granted: —
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Expires: 2009-08-15
Abstract
Abstract The construction and manufacture 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 akin 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 nucleous and annulus.
Inventors
- 👤 Alastair J. Clemow
- 👤 Elizabeth H. Chen
- 👤 Noshir A. Langrana
- 👤 John R. Parsons
- 👤 Casey K. Lee
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 04:29
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: 19
Claim 1
Independent Claim
77 words
A biocompatible intervertebral spacer comprising: a central core of a 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 stiffer elastomeric material surrounding said central core to approximate the size and shape of a natural annulus fibrosus; and endplates comprised of a suitably stiff biocompatible material and affixed, one to each end, to the outer ring central core.
Claim 2
Dependent Claim
77 words
A biocompatible intervertebral spacer comprising: a central core of a 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 stiffer elastomeric material surrounding said central core to approximate the size and shape of a natural annulus fibrosus; and endplates comprised of a suitably stiff biocompatible material and affixed, one to each end, to the outer ring central core.
Claim 3
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 4
Dependent Claim
26 words
A spacer according to Claim 1 or 2 wherein the outer ring surrounding said central core contains 1-5 layers of a biocompatible elastomer of varying hardness.
Claim 5
Dependent Claim
24 words
A spacer according to Claim 3 wherein the outer ring surrounding said central core contains 2-3 layers of a biocompatible elastomer of varying hardness.
Claim 6
Dependent Claim
17 words
A spacer according to any preceding claim wherein the biocompatible elastomer utilised is a thermoplastic polyurethane elastomer.
Claim 7
Dependent Claim
24 words
A spacer according to any preceding claim wherein the biocompatible elastomer utilised is the elastomer sold under the trade mark C-Flex (Registered Trade Mark).
Claim 8
Dependent Claim
12 words
A spacer according to any preceding claim wherein the endplates contain hydroxylapatite.
Claim 9
Dependent Claim
15 words
A spacer according to any of claims 1 to 6 wherein the endplates are metal.
Claim 10
Dependent Claim
19 words
A spacer according to claim 7 or 8 wherein the endplates have a porous metallic or polymeric sintered surface.
Claim 11
Dependent Claim
18 words
A spacer according to any preceding claim wherein the endplates provide for a mechanical interlock with adjacent bones.
Claim 12
Dependent Claim
18 words
A spacer according to any preceding claim wherein the endplates are fashioned for use with polymethylmethacrylate bone cement.
Claim 13
Dependent Claim
18 words
A spacer according to any preceding claim sized so as to approximate the size of a natural disc.
Claim 14
Dependent Claim
20 words
A spacer according to any preceding claim sized so as to approximate 30-80% of the size of a natural disc.
Claim 15
Independent Claim
60 words
A method for preparing a biocompatible intervertebral spacer, according to any preceding claim, wherein said method comprises: forming said central core by injection, transfer or compression molding; molding said outer ring around said central core, in a stepwise fashion, if more than one layer of elastomer is used; and applying said endplates to the molded core and outer ring assembly.
Claim 16
Dependent Claim
26 words
A method according to Claim 14, wherein the endplates are applied to the core/outer ring assembly by molding the endplates directly onto the core/outer ring assembly.
Claim 17
Dependent Claim
22 words
A method according to Claim 14, wherein the endplates are metal and are applied to the core/outer ring assembly using additional elastomer.
Claim 18
Dependent Claim
20 words
A method according to Claim 14 wherein the endplates are additionally coated with a layer of hydroxylapatite or polymeric material.
Claim 19
Dependent Claim
42 words
A spacer according to any of claims 1 to 16 for use in a method of alleviating the pain and/or paralysis of a damaged or diseased disc which comprises replacing all or part of the damaged or diseased disc with said spacer.
References Cited (Backward Citations)
US3867728A
Cited
EP0277282A1
Cited
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