Plus Endoprothetik Ag

Smith & Nephew Orthopaedics Ag

Plus Orthopedics Ag

Smith + Nephew

Intraplant Ag

Hans F Schmotzer

Peter Schuler

Udo Malzer

Lorenz Brunner

Yvo Dirix

Willi Horber

Christoph H&auml;ssig

Shilesh C Jani

Paul Smith

Theo Tervoort

Thomas Hauri

Bernhard Hauri

Werner Berner

Reto Lerf

Stephan Siegmann

Christoph Hassig

Christian Habegger

Olivier Zinger

A femoral slideway and femoral slideway/femur-size template combination is employed to create an installed knee prosthesis that creates a reduced amount of stress in the collateral ligaments relative to previous prosthesis. In one embodiment, the reduced stress is achieved by employing a femoral slideway/femur-size template combination which results in installation of a femoral slideway which has a smaller dorsal-ventral dimension than a corresponding dimension of the femur prior to resection.

Femoral slideway and method

Femoral slideway

Provided are processes comprising crosslinking polyethylene or using crosslinked polyethylene. Furthermore, the processes may include compacting and/or sintering the polyethylene. The polyethylene can comprise virgin ultrahigh molecular weight polyethylene having a weight average molecular weight of at least 1,000,000 g/mol, to provide a compacted composition comprising virgin ultrahigh molecular weight polyethylene.

Processes comprising crosslinking polyethylene or using crosslinked polyethylene

The present invention relates to highly cross-linked UHMWPE, which is possessed of an improved oxidation resistance, as well as a method for making the same. The UHMWPE material of the current invention is combined with an anti-oxidant compound or a free-radical scavenger prior to formation. Once the UHMWPE with the added material has been formed and treated with gamma or electron bean irradiation, it shows an improved wear resistance and also a good resistance to oxidation. Such a material, is particularly interesting for the field of making replacement joint implants.

Oxidation resistant highly-crosslinked UHMWPE

A prosthetic device may comprise an insert having a first surface configured to contact a first prosthetic component and a bearing surface configured to articulate against a second prosthetic component. The insert comprises an ultra-high molecular weight polyethylene and vitamin E. The vitamin E may have a concentration in the range of 0.02 to 0.12 wt % first mixed with the ultra-high molecular weight polyethylene and then molded with the ultra-high molecular weight polyethylene at a temperature greater than the melting point of the ultra-high molecular weight polyethylene. The ultra-high molecular weight polyethylene and vitamin E may be gamma irradiated with a dosage of radiation between 5 and 20 Mrad. The insert may be machined prior to gamma irradiating the insert in air such that the gamma irradiation, at suitably high dosages, may also sterilize the insert.

Ultra high molecular weight polyethylene for bearing surfaces

The invention relates to open-pore biocompatible surface layers for implants, which layers are arranged over virgin surfaces of the implants, wherein pores of the open-pore surface layers are connected to form coherent pore networks and the surface layers have a specific internal surface area of &#x2267;0.06 &#x3bc;m/&#x3bc;m, preferably &#x2267;0.035 &#x3bc;m/&#x3bc;mand especially &#x2267;0.025 &#x3bc;m/&#x3bc;m, measured by image analysis as a 2D-boundary line per unit of surface area in a metallographic microsection at 100&#xd7; magnification. The invention further relates to methods of producing such surface layers, to implants coated therewith and to possible uses of the surface layers.

Open-pore biocompatible surface layer for an implant, methods of production and use

The invention relates to a method of manufacturing implant parts made of highly cross-linked polyethylene, wherein a blank made of ultra-high-molecular-weight polyethylene is irradiated with ionizing radiation in order to produce radicals in the blank. To optimize the cross-linkage of the highly cross-linked polyethylene and to eliminate free radicals, the blank is subsequently treated by means of microwave radiation and/or ultrasound in such a way that free radicals, which have not recombined, are excited so as to ensure substantially complete recombination of the free radicals. The shape of the treated blank can then be adjusted by means of machining. The invention further relates to implant parts for application in human medicine that have been manufactured as described above.

Method for producing implant parts from highly cross-linked UHMWPE and implant parts for human medicine

A femoral slideway and a femoral slideway/femur-size template combination is employed to create an installed knee prosthesis that creates a reduced amount of stress in the collateral ligaments relative to previous prostheses. In one embodiment, the reduced stress is achieved by employing a femoral slideway/femur-size template combination which results in installation of a femoral slideway which has a smaller dorsal-ventral dimension than a corresponding dimension of the femur prior to resection.

A knee-joint prosthesis with a tibial part having a flat tibial bearing surface, with a bearing body that can be shifted thereon in the anterior-posterior direction and includes two concave bearing shells within which a femoral joint part can be movably seated, and with a rotational guide that permits rotation of the bearing body on the tibial bearing surface about an axis of rotation perpendicular to said surface. The rotation guide includes a steering rod that is seated at the bearing body so as to be pivotable relative thereto and at the tibial part is guided in the medial/lateral direction and/or rotationally guided.

Knee-joint endoprosthesis

The kit for implanting a cementable endoprosthesis includes a fitting instrument and at least two components to be implanted, namely an endoprosthesis shaft and a proximal centering and/or sealing element, the shaft and the fitting instrument being designed to be able to be coupled to each other, and the centering and/or sealing element being designed to be placeable on the shaft and to be displaceable in the direction of extension of the latter, and either the fitting instrument including a limit stop part which forms a limit stop relative to the centering and/or sealing element, or a marking being arranged on the fitting instrument and on the shaft in order to ensure a defined mutual position between the centering and/or sealing element and the shaft.

Kit for implanting a cementable endoprosthesis

A femoral hip-joint prosthesis having a tapered stem for implantation by cement. The prosthesis has a collarless shoulder at a proximal end and a stem extending therefrom to a distal end in tapered fashion. A logarithmically extending curvature of anterior and posterior side faces of a first subsidiary section of the stem combine with straight converging lines of a second subsidiary section of the stem to uniformly distribute pressure in the prosthesis within the femoral hip bone.

Femoral hip-joint prosthesis with a logarithmically extending curvature

A femur slide has a patella shield and two convex curved condyle cups which are anteriorly rigidly joined by the patella shield. The two condyle cups and the patella shield define internally anterior and posterior matching surfaces which correspond with a femural ventral cut and with a femural dorsal cut. Relative to a reference plane which is defined by posterior slide surfaces of the condyle cups, an anterio-medial matching surface lies nearer to the reference plane than an anterio-lateral matching surface. The anterior matching surfaces are defined by a slanted surface with is continuously slanted in a direction from lateral to medial to posterior, and an angle between the slanted surface and the reference plane lies between three and ten degrees.

Femoral sled prosthesis

The kit for implanting a cementable endoprosthesis comprises a fitting instrument ( ) and at least two components to be implanted, namely an endoprosthesis shaft ( ) and a proximal centering and/or sealing element ( ), the shaft ( ) and the fitting instrument ( ) being designed to be able to be coupled to each other, and the centering and/or sealing element ( ) being designed to be placeable on the shaft ( ) and to be displaceable in the direction of extension of the latter, and either the fitting instrument ( ) comprising a limit stop part ( ) which forms a limit stop relative to the centering and/or sealing element ( ), or a marking ( ) being arranged on the fitting instrument ( ) and on the shaft ( ) in order to ensure a defined mutual position between the centering and/or sealing element ( ) and the shaft ( ).

Cup for a knee-joint prosthesis

An apparatus for supporting and correcting a skeletal structure includes at least two anchoring elements for a connecting element. The connecting element includes an elongate tensioning element that can be fixed to the anchoring element. Spacer sleeves can be slid over the tensioning element in order to keep adjacent anchoring elements a predetermined distance apart when a pulling force is applied to the tensioning element. Each anchoring element is attachable to a bone or vertebra. Surfaces of the anchoring elements against which the spacer sleeves abut are spherically curved. An end face at an end of each spacer sleeve towards the anchoring element has a shape complementary to an associated supporting surface of the anchoring element. The anchoring element has a passage for the tensioning element, wherein entrance and exit openings of the passage passing through the anchoring element each expand outward on all sides in a conical or trumpet-like shape.

Growing community of inventors

Kölliken, Switzerland

Hans F Schmotzer