US4589883A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Femoral hip prosthesis
Assignee: Howmedica Osteonics Corp
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Filing: 1983-06-06
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Granted: 1986-05-20
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Expires: 2003-06-06
Abstract
Abstract A femoral hip prosthesis comprises a stem component generally divided into a proximal portion and a substantially longer distal portion. The stem has a slight posterior bow along its length. The proximal portion includes a slight twist of from about 5° to 15°, the twist extending in a direction from the anterior to the posterior face of the stem through the medial face thereof. The characteristics of the stem provide a glove fit when inserted into a prepared intermedullary canal in the femur.
Inventors
- 👤 Robert V. Kenna
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:03
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/32; A61F2/36; A61F2/3662; A61F2/367; A61F2/30767; A61F2002/30001; A61F2002/30316; A61F2002/30317; A61F2002/30322; A61F2002/30769; A61F2002/3678; A61F2002/3698; A61F2250/00; A61F2250/0014; A61F2250/0026; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00023; A61F2310/00029
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
109 words
A femoral hip prosthesis comprising a stem component with an anterior face, a posterior face, a lateral face and a medial face and having a proximal portion and a substantially longer distal portion, the stem being noncircular in cross section and exhibiting a slight posterior bow along its length, the stem further including a twist of from about 5° to 15° in the proximal portion, the twist extending in a direction from the anterior to the posterior face about the longitudinal axis of the stem, thereby providing a more accurate fit between the stem and an intramedullary cavity and positive resistance to rotation of the stem within the cavity.
Claim 2
Dependent Claim
109 words
A femoral hip prosthesis comprising a stem component with an anterior face, a posterior face, a lateral face and a medial face and having a proximal portion and a substantially longer distal portion, the stem being noncircular in cross section and exhibiting a slight posterior bow along its length, the stem further including a twist of from about 5° to 15° in the proximal portion, the twist extending in a direction from the anterior to the posterior face about the longitudinal axis of the stem, thereby providing a more accurate fit between the stem and an intramedullary cavity and positive resistance to rotation of the stem within the cavity.
Claim 3
Dependent Claim
34 words
A femoral hip prosthesis as in claim 1 wherein the length of the distal portion is from about 2 to 3 times the length of the proximal portion as measured along the medial face.
Claim 4
Dependent Claim
22 words
A femoral hip prosthesis as in claim 1 wherein the twist generally commences at the boundary of the distal and proximal portions.
Claim 5
Dependent Claim
16 words
A femoral hip prosthesis as in claim 3 wherein the twist extends throughout the proximal portion.
Claim 6
Dependent Claim
14 words
A femoral hip prosthesis as in claim 4 wherein the twist is about 9°.
Claim 7
Dependent Claim
20 words
A femoral hip prosthesis as in claim 1 wherein the exterior surface of the proximal portion includes a porous coating.
Claim 8
Dependent Claim
38 words
A femoral hip prosthesis as in claim 6 wherein the proximal portion is generally equally divided into a proximal segment, a central segment and a distal segment with a flare on the lateral face of the distal segment.
Claim 9
Dependent Claim
35 words
A femoral hip prosthesis as in claim 1 wherein the proximal portion is generally equally divided into a proximal segment, a central segment and a distal segment with a lateral flare on the distal segment.
Claim 10
Dependent Claim
34 words
A femoral hip prosthesis as in claim 8 including a neck extending from the proximal segment, the neck having an axis at an angle of about 45° to the general orientation of the stem.
Claim 11
Dependent Claim
22 words
A femoral hip prosthesis as in claim 9 wherein the neck is anteverted at an angle of from about 5° to 15°.
Claim 12
Dependent Claim
15 words
A femoral hip prosthesis as in claim 10 including a capitulum secured to the neck.
Claim 13
Dependent Claim
21 words
A femoral hip prosthesis as in claim 11 wherein the capitulum and the neck are secured together by a Morse fit.
Claim 14
Dependent Claim
17 words
A femoral hip prosthesis as in claim 1 wherein the stem is generally oblong in cross section.
Claim 15
Dependent Claim
32 words
A femoral hip prosthesis as in claim 1 wherein the twist extends in a direction from the anterior through the medial to the posterior face about the longitudinal axis of the stem.
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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) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |