A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents

A61F2/02—Prostheses implantable into the body

A61F2/30—Joints

A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof

A61F2002/30316—The prosthesis having different structural features at different locations within the same prosthesis; Connections between prosthetic parts; Special structural features of bone or joint prostheses not otherwise provided for

A61F2002/30317—The prosthesis having different structural features at different locations within the same prosthesis

A61F2002/30322—The prosthesis having different structural features at different locations within the same prosthesis differing in surface structures

A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents

A61F2/02—Prostheses implantable into the body

A61F2/30—Joints

A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof

A61F2002/30316—The prosthesis having different structural features at different locations within the same prosthesis; Connections between prosthetic parts; Special structural features of bone or joint prostheses not otherwise provided for

A61F2002/30317—The prosthesis having different structural features at different locations within the same prosthesis

A61F2002/30324—The prosthesis having different structural features at different locations within the same prosthesis differing in thickness

A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents

A61F2/02—Prostheses implantable into the body

A61F2/30—Joints

A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof

A61F2002/30316—The prosthesis having different structural features at different locations within the same prosthesis; Connections between prosthetic parts; Special structural features of bone or joint prostheses not otherwise provided for

A61F2002/30331—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit

A61F2002/30332—Conically- or frustoconically-shaped protrusion and recess

A61F2220/0033—Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof

A61F2250/0014—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis

A61F2250/0023—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis differing in porosity

A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof

A61F2250/0014—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis

A61F2250/0026—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis differing in surface structures

A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof

A61F2250/0014—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis

A61F2250/0036—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis differing in thickness

Abstract

There is described a bone replacement implant, especially as joint replacement, having an open-mesh, three-dimensional structure (1) at least partially covering its surface.  The surface structure (1) is divided over its extension into at least two discrete zones (A, B, C) having different mesh widths.  After the implantation, bone material grows into the three-dimensional structure.  The distribution of the zones of different mesh widths over the implant surface depends on the pore sizes of the natural spongiosa of the bone onto or into which the implant is to be attached or inserted.  <IMAGE>

Wenn die Langzeitfixation - wie bereits erwähnt - im Prinzip die an sie gestellten Erwartungen auch erfüllt, so weisen die bekannten Implantate jedoch den Nachteil auf, daß sie nur in Grenzen eine funktionale Einheit mit dem sie umgebenden Knochenmaterial bilden, in dem Sinne, daß aufgrund der unterschiedlichen Knochendichtestruktur in Bereichen des Implantates unterschiedliche Elastizitätsmoduln in der natürlichen Spongiosa des Knochens einer recht einheitlichen Oberflächenstruktur des Implantates gegenüberstehen.  If the long-term fixation - as already mentioned - but in principle, the expectations placed on them also met, the known implants have the disadvantage that they are only limited a functional unit with the surrounding bone material in the sense that because of the different bone structure in areas of the implant different elastic moduli are facing in the natural cancellous bone of a very uniform surface structure of the implant. In bestimmten Bereichen der Knochenspongiosa eines Röhrenknochens ist die Spongiosa von einer relativ großen Zellig- und Porigkeit zu den Gelenkenden hin, wohingegen es Bereiche gibt, wo die Zell- und Porengröße der Knochenspongiosa etwa um einen Faktor bis zu 3 kleiner ist als in dem erstgenannten Bereich.  In certain regions of the cancellous bone of a long bone, the cancellous bone of a relatively large Zellig- and porosity of the joint ends is gone, whereas there are areas where the cell and pore size of the cancellous bone about a factor of up to 3 is smaller than in the first-mentioned area ,Als Beispiel für einen solchen Röhrenknochen wird der menschliche Femur angegeben.  As an example of such bones of the human femur is specified. Es ist einleuchtend, daß die Knochentrapekel als Bestandteil der natürlichen Spongiosa in homogener Zellig- und Porigkeit nicht sämtlich gleich gut in die einheitliche Oberflächenstruktur des Implantates einwachsen können.  It is evident that the trabecular bones can well grow into the uniform surface structure of the implant as part of the natural cancellous bone in homogeneous Zellig- and porosity not all equal. Letztlich führt dies zu einer Verlängerung der Einheilphase und Umbauphase des knöchernen Lagers zum Implantat hin und zu einer Verkürzung der Langzeitfixation aufgrund der Tatsache, daß sozusagen Angehörige einer Knochentrapekelgruppe in die Oberflächenstruktur einwachsen, die nicht der Gruppe der an einer bestimmten Stelle der Spongiosa vorherrschenden Zelligkeit und Porigkeit zuzuordnen sind.  Ultimately, this leads up to a prolongation of healing and remodeling phase of the bone bed to the implant and to a shortening of the long-term fixation due to the fact that as it were members of a Knochentrapekelgruppe grow into the surface structure that is not the group of the prevailing at a particular place of the spongiosa cellularity and porosity are attributable. 

Gelöst wird die Aufgabe durch das Implantat mit den Merkmalen des Anspruchs 1.  Weitere vorteilhafte Ausgestaltungen ergeben aus den Unteransprüchen.  The object is achieved by the implant with the features of claim 1.  Further advantageous embodiments result from the subclaims. 

[0006] [0006]

Demgemäß wird vorgeschlagen, daß die Oberflächenstruktur des Implantates in ihrer flächigen Ausdehnung in zumindest zwei diskrete Zonen unterschiedlicher Maschenweiten unterteilt ist.  Accordingly, it is proposed that the surface structure of the implant is divided into its two-dimensional extent in at least two discrete zones of different mesh sizes. Bei dieser Festlegung wird unter flächiger Ausdehnung ein Oberflächenabschnitt des Implantates verstanden im Gegensatz zu der räumlichen Ausdehnung, welche auf die Dicke oder Stärke der Struktur abzielt.  In this setting, a surface portion of the implant is understood in contrast to the spatial extent, which is directed to the thickness or strength of the structure under an areal extent. 

[0007] [0007]

Die Maschenweiten der Zonen sind vorzugsweise der Zelligkeit und der Porigkeit des Knochenmaterials, welches nach der Implantation mit der Oberflächenstruktur des Implantates in Verbindung steht, angepaßt, in dem Sinne, daß die jeweiligen Maschenweiten der Zonen in etwa der Größe der Zellen und Poren der natürlichen Spongiosa entsprechen, welche in und an die Oberflächenstruktur des Implantates einwachsen soll.  The mesh sizes of the zones are preferably the cellular structure and the porosity of the bone material, which is connected after the implantation with the surface structure of the implant, adapted in the sense that the respective mesh sizes of the zones close to the size of the cells and pores of the natural cancellous bone corresponding to which is to grow into and on the surface structure of the implant. Für die Spongiosa mit einer kleinen Zell- und Porenweite wird demnach auf dem Implantat eine Struktur mit einer entsprechend kleinen Maschenweite vorgesehen.  Accordingly, a structure with a correspondingly small mesh aperture provided on the implant for the cancellous bone with a small cell and pore size. Umgekehrt wird für eine Spongiosa mit einer großen Zell- und Porenweite eine Zone auf dem Implantat mit einer entsprechend großen Maschenweite vorgesehen.  a zone Conversely provided on the implant with a correspondingly large mesh size for a cancellous bone with a large cell and pore size. 

[0008] [0008]

Die Zell- und Porenweiten der natürlichen Spongiosa in Röhrenknochen des Menschen ist katalogisierbar, so daß die Implantate in Anwendung dieses Katalogs mit entsprechenden Zonen unterschiedlicher Maschenweite hergestellt werden können, je nachdem, für welche Knochenpartie das Implantat bestimmt ist.  The cell and pore sizes of natural cancellous bone in long bones of humans is cataloged so that the implants can be made in application of this catalog with corresponding zones of different mesh sizes, depending on which section of bone, the implant is intended. 

Die größte Maschenweite einer Zone der Oberflächenstruktur beträgt 6 mm, die kleinste Maschenweite einer Zone 1,5 mm.  The largest mesh width of a zone of the surface structure is 6 mm and the smallest mesh width of a zone 1.5 mm. Sämtliche Bereiche zwischen diesen beiden Grenzwerten können vorgesehen sein in Abhängigkeit von der natürlichen Ausbildung der Spongiosa des Knochens, an oder in den das Implantat eingesetzt werden soll.  All the regions between these two limit values ​​may be provided depending on the natural formation of the spongiosa of the bone to or in which the implant is to be used. 

eine schematisierte Ansicht mehrerer Zonen der Oberflächenstruktur eines Implantates nach der Erfindung, und a schematic view of a plurality of zones of the surface structure of an implant according to the invention, and

Implant for use as bone replacement e.g. hip pedicle, has surface which is partially covered by open-mesh, three-dimensional network structure, where titanium plasma-layer is deposited on portion of surface of implant

Implant for use as bone replacement e.g. hip pedicle, has surface which is partially covered by open-mesh, three-dimensional network structure, where titanium plasma-layer is deposited on portion of surface of implant