US4041939A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surgical implant spinal screw
Assignee: Smiths Healthcare Ltd
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Filing: 1976-04-26
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Granted: 1977-08-16
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Expires: 1996-04-26
Abstract
Abstract Surgical implant, known as a spinal screw and nut, for use in securing a metal cable to a vertebrae in an operation for the correction of scoliosis.
Inventors
- 👤 John Emmett Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:15
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/56; A61B17/58; A61B17/68; A61B17/70; A61B17/7001; A61B17/7002; A61B17/7019; A61B17/7022; A61B17/84; A61B17/86; A61B17/8665; A61B17/7044
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
134 words
A surgical implant which comprises a combination of a metal spinal screw and a metal nut, wherein the screw has a head provided with a hole through which a metal cable can be passed, the head being capable of being deformed to prevent movement of the cable within the hole, and a shank having a relatively coarse self-tapping thread over a major portion of its length and, on an end portion remote from the head, a relatively fine thread of smaller external diameter, and wherein the nut has an internal thread compatible with the fine-threaded end portion of the shank of the screw, and a plastics insert adjacent to a portion of the internal thread and so arranged that, in use, it can engage a part of the fine-threaded end portion of the screw.
Claim 2
Dependent Claim
134 words
A surgical implant which comprises a combination of a metal spinal screw and a metal nut, wherein the screw has a head provided with a hole through which a metal cable can be passed, the head being capable of being deformed to prevent movement of the cable within the hole, and a shank having a relatively coarse self-tapping thread over a major portion of its length and, on an end portion remote from the head, a relatively fine thread of smaller external diameter, and wherein the nut has an internal thread compatible with the fine-threaded end portion of the shank of the screw, and a plastics insert adjacent to a portion of the internal thread and so arranged that, in use, it can engage a part of the fine-threaded end portion of the screw.
Claim 3
Dependent Claim
77 words
A surgical implant which comprises a metal spinal screw having a head provided with a hole through which a metal cable can be passed, the head being capable of being deformed to prevent movement of the cable within the hole, and a shank having a relatively coarse self-tapping thread over a major portion of its length proximate said head and, on an end portion remote from the head, a relatively fine nut-receiving thread of smaller external diameter.
Claim 4
Dependent Claim
77 words
A surgical implant which comprises a metal spinal screw having a head provided with a hole through which a metal cable can be passed, the head being capable of being deformed to prevent movement of the cable within the hole, and a shank having a relatively coarse self-tapping thread over a major portion of its length proximate said head and, on an end portion remote from the head, a relatively fine nut-receiving thread of smaller external diameter.
Claim 5
Dependent Claim
40 words
An implant as claimed in claim 1, wherein the length of the coarse-threaded portion of the screw is from 20 to 30 mm and the length of the fine-threaded end portion of the screw is from 5 to 10 mm.
Claim 6
Dependent Claim
14 words
An implant as claimed in claim 1, wherein the screw is made of titanium.
Claim 7
Dependent Claim
17 words
An implant as claimed in claim 1, wherein the plastics insert of the nut is of nylon.
Claim 8
Dependent Claim
12 words
An implant as claimed in claim 1, wherein the nut is hexagonal.
Claim 9
Dependent Claim
22 words
An implant as claimed in claim 1, wherein the plastics insert penetrates from a face of the nut to the internal thread.
Claim 10
Dependent Claim
18 words
An implant as claimed in claim 1, wherein the metal of which the nut is made is titanium.
Claim 11
Dependent Claim
40 words
An implant as claimed in claim 2, wherein the length of the coarse-threaded portion of the screw is from 20 to 30 mm and the length of the fine-threaded end portion of the screw is from 5 to 10 mm.
Claim 12
Dependent Claim
14 words
An implant as claimed in claim 2, wherein the screw is made of titanium.
References Cited (Backward Citations)
US1028795A
Cited
US2532296A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |