EP0282161B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Artificial spinal disc
Assignee: Health & Research Services Inc
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Filing: 1988-02-09
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Granted: 1992-08-12
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Expires: 2008-02-09
Abstract
Abstract An artificial disc for a human spine has upper (26) and lower (28) members hinged together at their rear portions and biased apart at their fronts by stiff coil springs (72). Rear stop surfaces (103) limit the opening movement of the members. Vertically projecting tabs (46,64) at the front and side of each member are rigidly screwed to the adjacent vertebrae. Tolerances between the pin (66) and apertures (60,62) of the hinge allow limited side to side rocking. The disc and screws are made of titanium alloy or cobalt chrome alloy. In a modified version the hinge pin (66) is replaced by cables tying the members together.
Inventors
- 👤 Thomas P. Hedman
- 👤 Geoffrey R. Fernie
- 👤 John P. Kostuik
- 👤 Brian E. Maki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 19:57
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/44; A61F2/442; A61F2/4425; A61F2002/30001; A61F2002/30316; A61F2002/30329; A61F2002/30462; A61F2002/30535; A61F2002/30565; A61F2002/30566; A61F2002/30568; A61F2002/30576; A61F2002/30578; A61F2002/30621; A61F2002/30624; A61F2002/443; A61F2220/00; A61F2220/0025; A61F2220/0075
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
154 words
An artificial disc (20, 20') for a human spine, being adapted to replace a natural disc and to be located between two vertebrae (80, 82) and comprising upper and lower members (26, 28), each having a rear portion and a front portion and having means (46, 64) for rigidly securing them to vertebrae (80, 82) respectively above and below them, and spring means (72, 74) between them to urge them apart, characterized in that the upper and lower members (26, 28) are provided with securing means (66; 110, 112, 114) adapted to secure them together and have a hinge or hinge-like means (38, 40, 42, 44, 54, 56, 60, 62, 66 or 106, 108) adapted to permit relative hinging motion of the upper and lower members (26, 28) about their rear portions; and in that the spring means (72, 74) are positioned between the upper and lower members to bias said front portions apart.
Claim 2
Dependent Claim
103 words
An artificial disc (20) according to claim 1 wherein said means (46) for rigidly securing said upper member (26) comprises at least two upwardly projecting tabs (46) adapted to overlie the side surfaces of said first vertebrae (80), and screws (94, 96) adapted to extend through said tabs (46) and into said first vertebrae (80), and said means for rigidly securing said lower member (28) comprises at least two downwardly projecting tabs (64) adapted to overlie the side surfaces of said second vertebrae (82), and screws (94, 96) adapted to extend through said downwardly projecting tabs (64) and into said second vertebrae (82).
Claim 3
Dependent Claim
51 words
An artificial disc (20) according to claim 2 wherein for each member (26, 28), one of said tabs (46, 64) is substantially at the center of the front of such member (26, 28) and a second one of said tabs (46, 64) is at the side of such member (26, 28).
Claim 4
Dependent Claim
42 words
An artificial disc (20) according to claim 3 wherein said second tab (46, 64) is substantially aligned in a front to rear direction with the axis of said hinge-like means (38, 40 42, 44, 54, 56, 60, 62, 66 or 106, 108).
Claim 5
Dependent Claim
28 words
An artificial disc (20) according to claim 4 wherein all of said screws (94, 96) are of length sufficient to penetrate substantially entirely through said vertebrae (80, 82).
Claim 6
Dependent Claim
38 words
An artificial disc according to claim 2, 3 or 4 wherein said tabs (46, 64) have holes therein at different levels for receiving said screws (94, 96), to prevent said screws (94, 96) from interfering with each other.
Claim 7
Dependent Claim
70 words
An artificial disc according to claim 1 wherein said hinge-like means (38, 40, 42, 44, 54, 56, 60, 62, 66 or 106, 108) includes means (70 or 110, 112 ,114) for permitting at least a limited amount of side to side rocking of said upper and lower members (26, 28) relative to each other about a vertical front to rear plane extending through the center of said members (26, 28).
Claim 8
Dependent Claim
30 words
An artificial disc according to claim 1, 2 or 3 wherein said means securing said upper and lower members (26, 28) together comprises a hinge pin (66) of the hinge.
Claim 9
Dependent Claim
87 words
An artificial disc according to claim 1, 2 or 3 wherein said means securing said upper and lower members (26, 28) together comprises a hinge pin (66) of the hinge extending through aligned holes (44, 60, 62) in said upper and lower members (26, 28), said holes (60, 62) having sufficient tolerance to allow a limited amount of side to side rocking of said members (26, 28) relative to each other about a vertical front to rear plane extending through the center of said members (26, 28).
Claim 10
Dependent Claim
93 words
An artificial disc according to claim 1, 2 or 3 wherein said means securing said upper and lower members (26, 28) together comprises a hinge pin (66) of the hinge extending through aligned holes (44, 60, 62) in said upper and lower members (26, 28), said holes (60, 62) having sufficient tolerance to allow a limited amount of side to side rocking of said members (26, 28) relative to each other about a vertical front to rear plane extending through the center of said members, said hinge pin (66) having tapered ends (70).
Claim 11
Dependent Claim
47 words
An artificial disc according to claim 1 wherein said means securing said upper and lower members (26, 28) together comprises a pair of cables (110), one at each side of said members (26, 28), each cable (110) being secured to said upper and lower members (26, 28).
Claim 12
Dependent Claim
23 words
An artificial disc according to claim 11 wherein said cables (110) extend through holes (112) in said upper and lower members (26, 28).
Claim 13
Dependent Claim
37 words
An artificial disc according to claim 1 wherein said upper and lower members (26, 28) have cooperating stop means (103) at said rear portions to limit the amount of opening hinging movement between said members (26, 28).
Claim 14
Dependent Claim
37 words
An artificial disc according to claim 1, 2 or 3 wherein said spring means comprises coil springs (72, 74) located forwardly of said hinge-like means (38, 40, 42, 44, 54, 56, 60, 62, 66 or 106, 108).
Claim 15
Dependent Claim
67 words
An artificial disc according to claim 1, 2 or 3 wherein said spring means comprises two pairs of coil springs (72, 74), said pairs being located side by side and forwardly of said hinge-like means (38, 40, 42, 44, 54, 56, 60, 62, 66 or 106, 108), each pair comprising an inner coil spring (74) and an outer coil spring (72) concentric with said inner coil spring.
Claim 16
Dependent Claim
42 words
An artificial disc according to claim 1, 2 or 3 wherein said upper and lower members (26, 28) and said spring means are all made of a bio-compatible alloy selected from titanium-6 aluminum-4 vanadium ELI alloy and a cobalt chrome molybdenum alloy.
Claim 17
Dependent Claim
31 words
An artificial disc according to claim 1, 2 or 3 wherein said spring means (72, 74) simulates the in vitro physiologic stiffness in a sagittal plane of a natural spinal disc.
Claim 18
Dependent Claim
40 words
An artificial disc according to claim 1, 2 or 3 wherein said spring means (72, 74) creates a resistive torque of between 1.4 and 2.3 newton metres per degree of compression (1.0 and 1.65 foot pounds per degree of compression).
References Cited (Backward Citations)
No citation records indexed.
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