Patent US5997541A successfully refreshed from Google Patents.
US5997541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Threaded washer
Assignee: Synthes USA LLC
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Filing: 1998-11-17
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Granted: 1999-12-07
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Expires: 2018-11-17
Abstract
Abstract A threaded washer with a central bore for use with a bone screw is disclosed. The washer is threaded into a counterbore extending below the bone surface and into cancellous bone material. The external washer threads are tapered to provide improved purchase. The bone screw is inserted through the central bore of the washer and threaded into the fragment beyond the fracture. The washer provides improved compressive forces while permitting the bone screw head to be located beneath the bone surface.
Inventors
- 👤 Beat Schenk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:13
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/56; A61B17/58; A61B17/68; A61B17/686; A61B17/84; A61B17/86; A61B17/8695; A61B2017/00004; Y; Y10; Y10S; Y10S606/00; Y10S606/907; Y10S606/908
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
99 words
A method for internal fixation of a first bone fragment to a second bone fragment, comprising: reaming the first bone fragment to produce a counterbore; installing a washer having a central hole and an external tapered thread into said counterbore; inserting a bond screw having a head through said central hole in said washer; rotating said bond screw so that a bone screw thread passes through the first bone fragment and engages the second bond fragment, and the bone screw head engages said washer; whereby said bone screw exerts a compressive force between the first and second bone fragments.
Claim 2
Independent Claim
99 words
A method for internal fixation of a first bone fragment to a second bone fragment, comprising: reaming the first bone fragment to produce a counterbore; installing a washer having a central hole and an external tapered thread into said counterbore; inserting a bond screw having a head through said central hole in said washer; rotating said bond screw so that a bone screw thread passes through the first bone fragment and engages the second bond fragment, and the bone screw head engages said washer; whereby said bone screw exerts a compressive force between the first and second bone fragments.
Claim 3
Independent Claim
85 words
A method of fixation of an outer bone fragment to an inner bone fragment, comprising: inserting a guide wire through the outer fragment and into the inner fragment; reaming a counterbore in the outer fragment; installing a washer having a central hole and an external, tapered thread into said counterbore; installing a cannulated, self-drilling bone screw through said central hole of said washer until a thread of said bone screw engages the second bone fragment and a head of said bone screw contacts said washer.
Claim 4
Independent Claim
85 words
A method of fixation of an outer bone fragment to an inner bone fragment, comprising: inserting a guide wire through the outer fragment and into the inner fragment; reaming a counterbore in the outer fragment; installing a washer having a central hole and an external, tapered thread into said counterbore; installing a cannulated, self-drilling bone screw through said central hole of said washer until a thread of said bone screw engages the second bone fragment and a head of said bone screw contacts said washer.
Claim 5
Dependent Claim
38 words
The method of claim 2, further comprising the step of turning said bone screw after said head of said bone screw contacts said washer, thereby reducing a gap between said bone fragments and compressing said bone fragments together.
Claim 6
Dependent Claim
10 words
The method of claim 2, wherein said washer is bioabsorbable.
Claim 7
Dependent Claim
17 words
The method of claim 4, further comprising the step of tapping said counterbore to accept said washer.
Claim 8
Dependent Claim
53 words
The method of claim 1, further comprising the steps of turning said bone screw after said head of said bone screw contacts said washer, wherein said head of said bone screw resides at a depth inside said outer fragment, thereby reducing a gap between said bone fragments and compressing said bone fragments together.
Claim 9
Dependent Claim
38 words
The method of claim 6, wherein the step of turning said bone screw after said head of said bone screw contacts said washer further comprises said head of said bone screw maintaining said depth inside outer bone fragment.
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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) | 2002-12-06 | 2003-06-07 | 2003-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-06 | 2007-06-07 | 2007-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-06 | 2011-06-07 | 2011-12-07 | $7700.00 | Window Closed / Lapsed |