摘要:
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.
摘要:
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.
摘要:
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 ≧0.06 μm/μm2, preferably ≧0.035 μm/μm2 and especially ≧0.025 μm/μm2, measured by image analysis as a 2D-boundary line per unit of surface area in a metallographic microsection at 100× magnification. The invention further relates to methods of producing such surface layers, to implants coated therewith and to possible uses of the surface layers.
摘要:
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.
摘要:
Provided are processes comprising crosslinking polyethylene or using crosslinked polyethylene. Furthermore, the processes may include compacting and/or sintering the polyethylene.
摘要:
A method of surface finishing a bone implant comprises the steps of roughening a surface of the implant by blasting with abrasive particles and then pickling the surface-roughened implant in a pickling solution in order to loosen any partially embedded abrasive blasting particles that may be contaminating the surface of the implant. Thereafter the roughened surface of the implant is cleaned by mechanical action to detach the loosened abrasive particles there from. The pickling and cleaning steps are not intended to produce any additional roughening of the treated surface, which should be structured to the required roughness by the initial abrasive blasting, typically such that the Ra and Rt roughness parameters are 3≦Ra≦7 μm and 20≦Rt≦70 μm respectively.
摘要:
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.
摘要:
The invention relates to an open-pore biocompatible surface layer for an implant, which layer is arranged over a virgin surface of the implant, wherein pores of the open-pore surface layer are connected to form a coherent pore network and the surface layer has an internal surface area of ≧0.06 μm/μm2, preferably ≧0.035 μm/μm2 and especially ≧0.025 μm/μm2, measured by image analysis as a 2D-boundary line per unit of surface area in a metallographic microsection at 100× magnification. The invention further relates to methods of producing such a surface layer, to an implant coated therewith and to possible uses of the surface layer.
摘要:
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.
摘要:
Metal socket (10) for a joint endoprosthesis, the outer surface (11) of which comprises at least three circumferentially extending surfaces (12, 13, 14) of spherical segments each having a different radius (R1, R2, R3). A metal socket for a joint endoprosthesis has an outer surface which includes at least three circumferentially extending, outwardly convex surface regions each having a different radius. The outwardly convex surface regions are exclusively surfaces of spherical segments, centers of which lie on a common axis of rotation, such that a radius of a medial spherical-segment surface is smaller than a radius of a polar spherical-segment surface, but larger than a radius of an equatorial spherical-segment surface.