US4079469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elbow joint endoprosthesis
Assignee: Individual
•
Filing: 1976-12-09
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Granted: 1978-03-21
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Expires: 1996-12-09
Abstract
Abstract A bone joint endoprosthesis is formed of a proximal member and a distal member. The former is a semi-cylindrical profiled body having a proximal flat chordal surface and a semi-circular T-slot concentric with the joint axis opening distally. The latter comprises an intramedullary stem and a proximal arcuate segment of I-shape cross-section whose free end is slidably carried in the T-slot. The unit allows for normal flexion and extension motion and joint stability is provided by the T-slot arrangement of the joint articulation.
Inventors
- 👤 Thomas Gordon Wadsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:29
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/38; A61F2/3804; A61F2002/30001; A61F2002/30316; A61F2002/30329; A61F2002/30383; A61F2002/3039; A61F2002/30398; A61F2/30767; A61F2/30771; A61F2002/30878; A61F2002/3827; A61F2002/3831; A61F2220/00; A61F2220/0025
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
174 words
An elbow endoprosthesis comprising: a humeral member and an ulnar member, said humeral member being a substantially semi-cylindrical, profiled body having a longitudinal axis coincident with the joint axis of the elbow endoprosthesis and comprising: a proximal flat chordal surface, a principal body portion, a flat radial lateral surface upon one side of said principal body portion, a semi-globular portion upon the other side of said principal body portion, a semi-cylindrical key extending medially of said lateral surface, and a cylindrical key extending proximal of said chordal surface, said ulnar member comprising: an intramedullary stem and a proximal segment integral with said stem, said segment comprising: a first annulus concentric with said joint axis and a T-shaped portion extending proximally of said annulus, the base of T being longitudinally aligned with said stem with the top of the T being a second annulus concentric with said first annulus, said humeral member principal body portion having a semi-circular T-slot concentric with said joint axis sized to slidably receive the T-shaped portion of said ulnar member.
Claim 2
Dependent Claim
174 words
An elbow endoprosthesis comprising: a humeral member and an ulnar member, said humeral member being a substantially semi-cylindrical, profiled body having a longitudinal axis coincident with the joint axis of the elbow endoprosthesis and comprising: a proximal flat chordal surface, a principal body portion, a flat radial lateral surface upon one side of said principal body portion, a semi-globular portion upon the other side of said principal body portion, a semi-cylindrical key extending medially of said lateral surface, and a cylindrical key extending proximal of said chordal surface, said ulnar member comprising: an intramedullary stem and a proximal segment integral with said stem, said segment comprising: a first annulus concentric with said joint axis and a T-shaped portion extending proximally of said annulus, the base of T being longitudinally aligned with said stem with the top of the T being a second annulus concentric with said first annulus, said humeral member principal body portion having a semi-circular T-slot concentric with said joint axis sized to slidably receive the T-shaped portion of said ulnar member.
Claim 3
Dependent Claim
19 words
The endoprosthesis of claim 1 which includes a button implant to replace a portion of the elbow radial head.
Claim 4
Dependent Claim
19 words
The endoprosthesis of claim 2 wherein said button implant comprises a proximal bearing element and a distal key portion.
Claim 5
Dependent Claim
19 words
The endoprostheses of claim 1 wherein said intramedullary stem includes a pair of opposed nipples distal of said segment.
Claim 6
Dependent Claim
19 words
The endoprosthesis of claim 1 wherein said keys of said humeral member have at least one peripheral groove therein.
Claim 7
Dependent Claim
13 words
The endoprosthesis of claim 1 wherein said humeral member is formed of plastic.
Claim 8
Dependent Claim
12 words
The endoprosthesis of claim 6 wherein said plastic is high density polyethylene.
Claim 9
Dependent Claim
13 words
The endoprosthesis of claim 1 wherein said ulnal member is made of metal.
Claim 10
Dependent Claim
11 words
The endoprosthesis of claim 8 wherein said metal is chrome cobalt.
Claim 11
Dependent Claim
122 words
A bone joint endoprosthesis comprising: a proximal member and a distal member said proximal member being a substantially semi-cylindrical profiled body having a longitudinal axis concentric with the joint axis of the endoprosthesis and comprising a proximal flat chordal surface, a principal body portion a semi-globular portion coaxial with said principal body portion providing a distal surface to act as a bearing surface and a semi-circular T-slot in said principal body portion concentric with said longitudinal axis, said distal member comprising an intramedullary stem and a proximal arcuate segment of I-shape cross-section integral with said stem, the proximal part of said segment being of size to fit within said T-slot and hold said distal member in sliding engagement with said proximal member.
Claim 12
Dependent Claim
122 words
A bone joint endoprosthesis comprising: a proximal member and a distal member said proximal member being a substantially semi-cylindrical profiled body having a longitudinal axis concentric with the joint axis of the endoprosthesis and comprising a proximal flat chordal surface, a principal body portion a semi-globular portion coaxial with said principal body portion providing a distal surface to act as a bearing surface and a semi-circular T-slot in said principal body portion concentric with said longitudinal axis, said distal member comprising an intramedullary stem and a proximal arcuate segment of I-shape cross-section integral with said stem, the proximal part of said segment being of size to fit within said T-slot and hold said distal member in sliding engagement with said proximal member.
References Cited (Backward Citations)
US3547115A
Cited
US3798679A
Cited
US3869729A
Cited
US3919725A
Cited
US3852831A
Cited
US3816854A
Cited
US3990116A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-03-20 | 1981-09-19 | 1982-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-20 | 1985-09-19 | 1986-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-20 | 1989-09-19 | 1990-03-21 | $7700.00 | Window Closed / Lapsed |