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US5443520A Expired / Lapsed US ⏱️ 0.0 years remaining

Cementless fixation element for an artificial hip joint with rotating cover element

Assignee: Smith and Nephew Orthopaedics AG
•
Filing: 1993-12-07
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Granted: 1995-08-22
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Expires: 2013-12-07
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Abstract

Abstract A metal fixation element is disclosed for receiving a plastic socket component of an artificial hip joint. The fixation element includes a frontal region which faces the pelvic bone. The frontal region has a central bore, with a screw thread to receive an insertion tool. The element also includes at least one conically tapering wall spaced from the frontal region. A self-tapping screw thread on the outer surface of the tapering wall provides for cementless fixation of the element in the pelvic bone. There is further provided an additional conically tapering wall between the frontal region and the first conically tapering wall. Three apertures are located in the frontal region. A cover element is rotatably mounted within the fixation element closely abutting the frontal region. The cover element has three equally spaced openings separated by continuous positions for selective opening and closing of the three apertures in the frontal region.

Inventors

  • 👤 K. Zweymuller
  • 👤 Andre Deckner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:59
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/32; A61F2/34; A61F2/30721; A61F2/30744; A61F2/46; A61F2/4603; A61F2/4609; A61F2002/30001; A61F2002/30316; A61F2002/30329; A61F2002/30433; A61F2/30767; A61F2/30771; A61F2002/3082; A61F2002/30827; A61F2002/3085; A61F2002/30858; A61F2002/30873; A61F2002/3401; A61F2002/3403; A61F2002/3406; A61F2002/3453; A61F2002/3462; A61F2220/00; A61F2220/0025; A61F2220/0041; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00023

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 134 words
A fixation element for receiving a socket component of an artificial hip joint, comprising: a frontal region for facing a pelvic bone and having a screw-threaded central bore to receive an insertion tool and said frontal region having at least one aperture therein; a first conically tapering wall located adjacent said frontal region and having an outer surface including a self-tapping screw thread for cementless fixation of the element in the pelvic bone; a second conically tapering wall disposed between said frontal region and said first conically tapering wall; a cover element to close said at least one aperture defined by the frontal region, said cover element engages to an inner surface of said frontal region and having a rotational axis perpendicular to said frontal region, said cover element being rotated on said axis.
Claim 2
Dependent Claim 134 words
A fixation element for receiving a socket component of an artificial hip joint, comprising: a frontal region for facing a pelvic bone and having a screw-threaded central bore to receive an insertion tool and said frontal region having at least one aperture therein; a first conically tapering wall located adjacent said frontal region and having an outer surface including a self-tapping screw thread for cementless fixation of the element in the pelvic bone; a second conically tapering wall disposed between said frontal region and said first conically tapering wall; a cover element to close said at least one aperture defined by the frontal region, said cover element engages to an inner surface of said frontal region and having a rotational axis perpendicular to said frontal region, said cover element being rotated on said axis.
Claim 3
Dependent Claim 33 words
The element as claimed in claim 1, wherein said second conically tapering wall defines a conical angle α which is larger than a conical angle β defined by said first conically tapering wall.
Claim 4
Dependent Claim 27 words
The element as claimed in claim 1, wherein said second conically tapering wall defines a conical angle α which is in a range 30° to 60° inclusive.
Claim 5
Dependent Claim 22 words
The element as claimed in claim 3, wherein said second conically tapering wall defines the conical angle α which is 45° .
Claim 6
Dependent Claim 39 words
The element as claimed in claim 1, wherein said frontal region defines a circumference of 180° and includes three apertures which are of substantially equal size and which are uniformly spaced about said circumference defined by said frontal region.
Claim 7
Dependent Claim 22 words
The element as claimed in claim 5, wherein each aperture extends over substantially 60° of said circumference defined by said frontal region.
Claim 8
Dependent Claim 42 words
The element as claimed in claim 1, wherein said cover element is a substantially disk-shaped member defining a circumference of 180° and includes three openings which are of substantially equal size and are uniformly spaced about the circumference of said cover element.
Claim 9
Dependent Claim 24 words
The element as claimed in claim 7, wherein said three openings are separated by a substantially 60° of the circumference of said cover element.
Claim 10
Dependent Claim 28 words
The element as claimed in claim 1, wherein said frontal region includes a longitudinal axis of rotation which coincides with said axis of rotation of said cover element.
Claim 11
Dependent Claim 26 words
The element as claimed in claim 9, wherein a tubular rivet rotatably attaches said cover element to said frontal region, said rivet including said screw-threaded bore.
Claim 12
Dependent Claim 27 words
The element as claimed in claim 1, including means attaching said cover element is attached to said frontal region under a compression force and with no tolerance.
Claim 13
Dependent Claim 40 words
The element as claimed in claim 1, wherein said first conically tapering wall includes an inner circumferential surface and includes at least one circumferential groove adapted to engage a correspondingly arranged projection on an outer surface of said socket component.
Claim 14
Dependent Claim 51 words
The element as claimed in claim 1, wherein each of said frontal region and said first conically tapering wall and said second conically tapering wall each include an outer surface, and are roughened on at least their outer surfaces with a mean roughness of 5 μm, according to a Gaussian distribution.
Claim 15
Dependent Claim 60 words
The element as claimed in claim 1, wherein said self-tapping screw thread comprises a plurality of teeth, each tooth having a geometric configuration corresponding to a configuration of the corresponding socket component of the artificial hip joint, the configuration including a thickness and height of which substantially correspond to a thickness and height of said socket component for use therewith.
Claim 16
Dependent Claim 45 words
The element as claimed in claim 1, wherein said self-tapping screw thread comprises a plurality of teeth, a shape of each tooth being constructed in accordance with the qualities of hardness and porosity of said pelvic bone into which the element is to be fixed.

References Cited (Backward Citations)

US4662891A Cited
US4919676A Cited
US5009666A Cited
US5074881A Cited
FR2676172A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-08-21 1999-02-20 1999-08-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-08-21 2003-02-20 2003-08-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-08-21 2007-02-20 2007-08-22 $7700.00 Window Closed / Lapsed

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