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US 5,580,353 AGranted
Prosthetic patella implant of the knee joint
AssigneeNone recorded
InventorsDavid Mendes, Ruth Beer
Life of this patent
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AssigneeNone recorded
InventorsDavid Mendes, Ruth Beer
Estimating the term…
A patella (knee cap) implant for fixation to the remaining portion of a natural patella and for sliding over a femoral articulating member, the implant including an upper surface, typically convex, for sliding over the femoral articulating member, typically a groove, and a concave undersurface for fixation to the remaining portion of the natural patella. Also provided is a tool for preparing the natural patella to accept a patella implant and a method for surgically fixing the patella implant.
A patella implant adapted to structurally fit a remaining part of the natural patella with maximal reserving of healthy natural tissue and minimal wear of the implant, comprising:
A patella implant adapted for light weight patients, the implant adapted to structurally fit a remaining part of the natural patella with maximal reserving of healthy natural tissue and minimal wear of the implant, comprising:
Dependencies are inferred from the claim text.
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No related US applications are recorded in the indexed filing history.
For elbows or knees: patellae or trochleae
For the knee: for the patella
Convex polygonal shapes: square
Applied in original prostheses, e.g. holes or grooves: with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels,…
Term ended 19 Jan 2015 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
The present invention relates to surgical implants or prosthetics and, more particularly, to a design for an artificial patella, or knee cap, and methods and tools for its installation.
Joint replacement is becoming increasingly widespread. One of the most widely practiced joint replacement involves the knee joint. In many cases, the replacement of the knee joint with a prosthetic also involves the replacement of a portion of the patella with a prosthetic.
Partial replacement of the patella is widely used in the surgical replacement of a damaged portion of the knee joint. However, it is known that, in a significant percentage of the cases, the patella implant typically fails after five to fifteen years. One of the typically occurring failures is near or at the periphery of the circular or elliptical patella implant, where the thickness of the patella implant material, typically high molecular weight high density polyethylene (HDPE), is at its smallest. A failing patella could lead to significant pain in the patient and typically requires a second operation to replace the failed patella implant.
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a perspective view of a typically artificial knee joint;
FIG. 2 is a side view of an artificial knee joint as in FIG. 1 showing the patella, quadriceps tendon and patella tendon;
The present invention is of a patella implant which can be used in the surgical repair of knee joints.
The principles and operation of a patella implant according to the present invention may be better understood with reference to the drawings and the accompanying description.
Referring now to the drawings, FIG. 1 illustrates a typical knee joint prosthetic. The knee joint is formed between the lower end of the femur 10 and the upper end of the tibia 12. In a total knee replacement, the lower end of femur 10 is replaced with a femoral prosthetic component 14 while the upper end of tibia 12 is replaced with a tibial prosthetic component 16.