Cap component for an endoprosthesis, and an endoprosthesis or artificial joint including the component - Patents.com

Abstract

The present invention relates to an endoprosthesis (30) comprising a cap component (20) and an insert component (10), the sliding surface of the insert component (10) being in sliding contact with the sliding surface of the cap component (20). The cap component (20) is designed to surround a part or all of an associated bone joint. The cap component (20) has a sliding surface that is convex or flat. Furthermore, the cap component (20) and / or the base material (22) of the cap component (20) have a stiffness, in particular an elastic modulus, similar to the bone material of the associated bone joint. Furthermore, the insert component (10) is designed to be inserted into the associated bone joint or to partially or completely replace the bone joint. Furthermore, the insert component (10) has a sliding surface that is convex or flat.

Description

[Technical field]

[0001] The present invention relates to a cap component for an endoprosthesis (resurfacing of an articular region) and to an endoprosthesis having such a cap component and an insert component (resurfacing of both articular regions). [Background technology]

[0002] Typically, damaged joints in humans and animals are completely or partially replaced with endoprostheses. Using the example of hip joint endoprostheses, in particular corresponding total endoprostheses, it is common to replace in each case both the acetabulum and the femoral head as a whole. However, this typical procedure may be associated with several drawbacks that may occur similarly to other joint types: increased risk of fractures, especially in the region of the artificial joint head, impingement of the femoral neck, malposition of the acetabulum, malposition of the femoral varus, poor attachment or osseointegration of the endoprosthesis to the bone, necrosis caused, for example, by the heat of the corresponding reamers used or by the corresponding joint, induction of (pseudo)tumors and / or allergies, in particular allergies due to metal particles or ions typically made of cobalt or chromium, caused, for example, by wear of metal-on-metal endoprostheses. At least some of the aforementioned drawbacks are caused or favored by the relatively large bone resections associated with the corresponding implants.

[0003] EP 2872072 discloses a cup for hip joint prosthesis that overcomes or reduces the risk of the above-mentioned drawback of metal particle release in the patient's body. Disadvantageously, the corresponding bone resections necessary for implant placement cannot be minimized with the described cup.

[0004] Furthermore, DE 102020116929 A1, published after the priority date of this application, shows an endoprosthesis with an attachment area for direct or indirect attachment to a mammalian bone and a sliding surface arranged at least partially to delimit the joint gap of the artificial joint and forming a sliding pair with at least one artificial or natural joint component. In this connection, it is important that the attachment area is part of the prosthesis body, which at least partially comprises a polymer or metal, and that the sliding surface is arranged on the prosthesis body and comprises a ceramic material in at least some areas. However, even the aforementioned endoprostheses do not sufficiently avoid or completely overcome the above-mentioned disadvantages. Summary of the Invention [Problem to be solved by the invention]

[0005] (Problems and Solutions) It is therefore an object of the present invention to provide a cap component for an endoprosthesis, and an endoprosthesis including such a cap component and an insert component, in which bone resection associated with the corresponding implant is minimized.

[0006] This object is achieved with respect to a cap component for an endoprosthesis by the features of claim 1. This object is achieved with respect to an endoprosthesis comprising such a cap component and an insert component by the features of claim 15. The dependent claims contain advantageous developments. [Means for solving the problem]

[0007] According to a first aspect of the present invention, a cap component for an endoprosthesis is produced. The cap component is designed to surround a part or all of an associated bone joint. Furthermore, the cap component and / or the base material of the cap component have a stiffness, in particular an elastic modulus, similar to the bone material of the associated bone joint, and the surface of the cap component facing the bone joint is partially or completely coated with a first metal or particles of the first metal. The cap component also has a convex or flat sliding surface.

[0008] It should also be noted that there are certain advantages if the base material of the cap component also acts as the sliding material on the side facing the joint.

[0009] Advantageously, the aforementioned configuration allows the corresponding bone resection required for the implantation of the cap component to be minimized. In particular, the surfaces of the relevant bone joints can be regenerated with minimal bone resection. Furthermore, the metal or metal particle coating promotes the growth of the cap component and improves the corresponding osseointegration. Furthermore, the risk of necrosis is reduced, for example, especially since minimal bone resection during implantation means that little heat is generated by the reamer. Furthermore, the use of cement can be completely omitted during implantation, which also prevents possible necrosis.

[0010] For the sake of completeness, it should also be mentioned that the cap component can also be used alone, i.e. without interacting with other components, in particular with prosthetic components, such as artificial joint sockets for endoprostheses. It is thus possible for the cap component to interact directly with a bone joint of a human or animal, or for the sliding surface of the cap component to interact with a sliding surface of a human or animal.

[0011] According to a first preferred embodiment of the first aspect of the present invention, the elastic modulus is less than 10 GPa, preferably less than 8 GPa, particularly preferably less than 5 GPa, very particularly preferably less than 1.5 GPa. Additionally or alternatively, the stiffness, in particular the elastic modulus, of the sliding surface of the cap component is similar or identical to the stiffness, in particular the elastic modulus, of the cap component and / or the substrate of the cap component.

[0012] Advantageously, for example, the biomechanical properties of a corresponding endoprosthesis can be improved.

[0013] According to a second preferred embodiment of the first aspect of the present invention, the substrate of the cap component is softer than the substrate of the second metal and / or metal alloy, in particular the insert component, which slidably cooperates with the cap component. Additionally or alternatively, the second metal is preferably titanium, iron, chromium or cobalt. Additionally or alternatively, the metal alloy preferably comprises at least one of the metals titanium, iron, chromium, cobalt.

[0014] Advantageously, the hardness of the base material of the cap component can be further improved, for example in the direction of optimal biomechanical properties of the corresponding endoprosthesis.

[0015] According to a further preferred embodiment of the first aspect of the present invention, the first metal comprises titanium particles, which are preferably applied by a titanium plasma spray coating process.

[0016] As an alternative to the titanium plasma spray coating process mentioned above, it can in principle be a thermal, thermal and pressure or non-thermal assisted coating process, in particular a pressing, sintering or vibration process or a pressing process.

[0017] As a further alternative, the surface of the cap component facing the bone interface may be partially or completely doped with particles of the first metal or the second metal.

[0018] Advantageously, titanium or particles thereof have proven to be particularly suitable for improving the corresponding osseointegration.

[0019] As an alternative to titanium, it may be advantageous to use calcium, preferably calcium compounds, particularly preferably calcium phosphate compounds, very particularly preferably hydroxyapatite or brookite.

[0020] According to a further preferred embodiment of the first aspect of the present invention, the substrate of the cap component comprises or consists of a plastic, preferably polyethylene, particularly preferably cross-linked stabilized polyethylene, very particularly preferably cross-linked stabilized polyethylene mixed with vitamin E.

[0021] In particular, said plastic may have a modulus of elasticity of up to 1 GPa. Moreover, the plastic may alternatively be a non-metallic and non-ceramic plastic material. In particular, it may be a polymer, preferably a highly cross-linked polyethylene or polyetheretherketone (PEEK) doped with vitamin E.

[0022] Advantageously, for example, an optimum can be achieved with regard to the biomechanical properties of the corresponding endoprosthesis. Furthermore, the base material or the cap component is transparent to X-rays, which makes it particularly easy to monitor the associated bone joints.

[0023] According to a further preferred embodiment of the first aspect of the present invention, the cap component comprises at least one anti-rotation element, which is preferably arranged on a surface of the cap component facing the bone interface.

[0024] Advantageously, in this way a reliable positioning of the cap component can be ensured, for example preemptively preventing corresponding misalignment.

[0025] According to a further preferred embodiment of the first aspect of the invention, the at least one anti-rotation element has the shape of a bar, a bollard, a thread, a tooth, a cross, a star or an anchor pin, in particular a peg. Additionally or alternatively, the at least one anti-rotation element is arranged in a circular and / or corresponding pole with respect to the cap component.

[0026] Advantageously, the cap component can be reliably positioned in a particularly efficient manner.

[0027] According to a further preferred embodiment of the first aspect of the present invention, the cap component comprises at least one anti-translation element, which is preferably arranged on a surface of the cap component facing the bone interface.

[0028] Advantageously, in this way a reliable positioning of the cap component can be ensured, for example preemptively preventing corresponding misalignment.

[0029] According to a further preferred embodiment of the first aspect of the invention, the at least one anti-translation element has the form of a groove, preferably an annular groove, or at least one cavity, preferably several cavities, particularly preferably several cavities evenly distributed on the corresponding surface, most preferably several golf ball shaped cavities.

[0030] Advantageously, a golf ball-shaped structure has proven to be particularly suitable for secure positioning of the cap component, in particular since the corresponding cavity can be manufactured in a particularly efficient manner.

[0031] According to a further preferred embodiment of the first aspect of the present invention, the at least one anti-rotational element and / or the at least one anti-translation element are configured to absorb forces and / or moments immediately after corresponding implantation and / or over time after corresponding growth of the bone material of the associated bone interface.

[0032] The advantage of this is that failures can be efficiently prevented not only during but also after implantation, which means that the cap components are reliably positioned throughout their entire useful life.

[0033] According to a further preferred embodiment of the first aspect of the present invention, the cap component comprises at least one recess, which is preferably designed to protect a critical blood supply zone during the corresponding preparation and / or implantation.

[0034] Advantageously, the aforementioned protection of zones with a vital blood supply can be achieved in a particularly efficient or preferred manner.

[0035] According to a further preferred embodiment of the first aspect of the invention, the shape of the cap component is such that the surface facing away from the associated bone joint deviates from a sphere and / or tapers, particularly on the underside of the corresponding equator of the cap component.

[0036] Preferably, the offset and / or taper is with respect to the sliding surfaces of the cap component.

[0037] Advantageously, for example, corresponding impingement may be avoided or prevented.

[0038] According to a further preferred embodiment of the first aspect of the invention, the shape has two different radii. Additionally or alternatively, the shape is based on an ellipse or a freely defined curve or line, whereby a femoral head-neck offset of in particular at least 0.5 mm, preferably at least 2 mm, particularly preferably at least 3 mm, very particularly preferably at least 5 mm is achieved.

[0039] According to a further preferred embodiment of the first aspect of the invention, the shape of the cap component is such that its shape deviates from a sphere on the surface facing the bone interface, in particular on the underside of the corresponding equator of the cap component.

[0040] Preferably, the above-mentioned deviation does not concern the sliding surfaces of the cap component, and in particular concerns the surfaces of the cap component which are partially or completely coated with the first metal or with particles of the first metal.

[0041] It is therefore advantageous to be able to fix the cap component to the associated bone connection in a particularly reliable and efficient manner, even when no bonding takes place.

[0042] According to a second aspect of the present invention, there is provided an endoprosthesis comprising an insert component for a first bone, in particular a first bone joint, the insert component having a concave or flat sliding surface, and a cap component according to one of the embodiments of the first aspect of the present invention for a second bone, in particular a second bone joint, the cap component being in sliding contact with the sliding surface of the cap component.

[0043] In addition to the numerous advantages of the insert and cap components, the sliding system is advantageously not a metal-to-metal system, which means that metal particles do not enter the corresponding biological tissue, preventing e.g. (pseudo)tumours and allergies.

[0044] It should be noted that the insert component may in particular be a joint socket, for example a hip socket.

[0045] According to a first preferred embodiment of the second aspect of the invention, the insert component is designed to be inserted into or partially or completely replace an associated bone interface, in particular a first bone interface. Additionally or alternatively, the surface of the insert component facing the bone interface, in particular the first bone interface, is partially or completely coated with a first metal or particles of a first metal. Furthermore, additionally or alternatively, the substrate of the insert component comprises a second metal or metal alloy and / or a metal oxide or a metal oxide mixture.

[0046] It can be particularly advantageous if the modulus of elasticity of the substrate of the insert component and the substrate of the cap component differs by a factor of at least 50, preferably at least 70, particularly preferably at least 100 and very particularly preferably at least 200. In this context, in particular, the modulus of elasticity of the insert component is greater than the modulus of elasticity of the cap component.

[0047] Advantageously, the aforementioned configuration allows the corresponding bone resection required for implantation of the insert component to be minimized. In particular, the surfaces of the relevant bone joints can be regenerated with minimal bone resection. Furthermore, the metal or metal particle coating promotes the growth of the insert component and improves the corresponding osseointegration. Furthermore, the risk of necrosis is reduced, since, for example, in particular, minimal bone resection during implantation means that little heat is generated by the reamer. Furthermore, the use of cement can be completely omitted during implantation, which also prophylactically prevents the possibility of necrosis.

[0048] According to a second preferred embodiment of the second aspect of the present invention, the metal oxide is or comprises yttrium oxide, zirconium oxide or aluminium oxide. Additionally or alternatively, the metal oxide mixture comprises at least one metal oxide of yttrium oxide, zirconium oxide or aluminium oxide, or is a mixture of yttrium oxide, stabilized zirconium oxide and aluminium oxide. Additionally or alternatively, the substrate of the cap component is softer than the second metal and / or metal alloy of the insert component.

[0049] Advantageously, the aforementioned oxides have proven to be particularly suitable for resurfacing the relevant bone joints with minimal bone resection.

[0050] According to a further preferred embodiment of the second aspect of the invention, the first metal of the insert component comprises titanium particles, which are preferably applied by a titanium plasma spray coating process.

[0051] Advantageously, titanium or particles thereof have proven to be particularly suitable for improving the corresponding osseointegration.

[0052] According to a further preferred embodiment of the second aspect of the present invention, the insert component comprises at least one anti-rotational and / or anti-translation element, preferably arranged on a surface of the insert component facing the bone interface.

[0053] Advantageously, in this way a reliable positioning of the insert component can be ensured, for example preemptively preventing corresponding misalignment.

[0054] According to a further preferred embodiment of the second aspect of the invention, the at least one anti-rotation and / or anti-translation element has the form of at least one tooth, preferably a toothed macrostructure, or at least one cavity, preferably several cavities, particularly preferably several cavities evenly distributed on the corresponding surface, most preferably several golf ball-shaped cavities.

[0055] Advantageously, a golf ball-shaped structure has proven to be particularly suitable for secure positioning of the insert component, in particular since the corresponding cavity can be manufactured in a particularly efficient manner.

[0056] According to a further preferred embodiment of the second aspect of the present invention, the first bone is the pelvis and the first bone joint is the acetabulum, and the second bone is the femur and the second bone joint is the femoral head.

[0057] Advantageously, the hip joint can be repaired but not completely replaced, rather the corresponding surfaces of the bone joint are regenerated or corrected, thereby minimizing the corresponding bone resection during implantation.

[0058] It is particularly advantageous if the corresponding sliding surfaces are preferably replaced or refurbished.

[0059] The embodiments described below show that an endoprosthesis according to the invention, which comprises an insert component according to the invention and a cap component according to the invention, can be used advantageously in a particularly flexible manner.

[0060] According to a further preferred embodiment of the second aspect of the present invention, the first bone is the tibia and the second bone is the talus.

[0061] According to a further preferred embodiment of the second aspect of the present invention, the first bone is the tibia and the second bone is the femur.

[0062] According to a further preferred embodiment of the second aspect of the present invention, the first bone is a phalangeal bone and the second bone is a metatarsal bone.

[0063] According to a further preferred embodiment of the second aspect of the present invention, the first bone is the glenoid cavity and the second bone is the humerus.

[0064] According to a further preferred embodiment of the second aspect of the present invention, the first bone is the radius and the second bone is the navicular bone.

[0065] According to a further preferred embodiment of the second aspect of the present invention, the first bone and the first bone joint are part of a human skeleton, and the second bone and the second bone joint are part of a human skeleton.

[0066] According to a further preferred embodiment of the second aspect of the present invention, the first bone and the first bone joint are part of an animal skeleton, and the second bone and the second bone joint are part of an animal skeleton. In the following, a detailed illustrative description of some embodiments of the invention is given with reference to the drawings. [Brief description of the drawings]

[0067] [Figure 1]1 illustrates an exemplary embodiment of an endoprosthesis according to the present invention. [Diagram 2] FIG. 2 shows only the cap component of the endoprosthesis according to FIG. 1. [Diagram 3] 2 shows an exemplary use of the endoprosthesis according to FIG. 1 as a hip joint endoprosthesis. [Figure 4] FIG. 4 shows a possible further use of at least a part of the hip endoprosthesis according to FIG. 3 in the case of a follow-up operation. [Figure 5A] 2 is a detailed cross-sectional view of an exemplary embodiment of a cap component according to the present invention. [Figure 5B] 5B shows a further view of the embodiment according to FIG. 5A. [Figure 5C] 5B shows exemplary rib shapes for the ribs included in the embodiment according to FIG. 5A. [Figure 5D] 11A-11C are diagrams of further exemplary embodiments of a cap component according to the present invention; [Figure 6A] 1 shows a detailed cross-sectional view of a further exemplary embodiment of a cap component according to the present invention; [Figure 6B] 1 shows a detailed cross-sectional view of a further exemplary embodiment of a cap component according to the present invention; [Figure 6C] 6B shows a three-dimensional view of the embodiment according to FIG. 6A. [Figure 6D] FIG. 6C is a three-dimensional view of the embodiment according to FIG. 6B. [Figure 7A] 1 shows a three-dimensional view of an exemplary embodiment of an insert component according to the present invention; [Figure 7B] 1 shows a three-dimensional view of a further exemplary embodiment of an insert component according to the invention; [Figure 8A] 13A-13D show views of a further exemplary embodiment of a cap component according to the present invention, in particular together with a humerus; [Figure 8B] 1 shows a further exemplary embodiment of a cap component according to the present invention, in particular with a femoral head; [Figure 8C]13A-13D show views of a further exemplary embodiment of a cap component according to the present invention, in particular together with a talus; [Figure 8D] 13 shows a further exemplary embodiment of a cap component according to the present invention, in particular with a femoral condyle; [Figure 8E] 13A-13C show views of a further exemplary embodiment of a cap component according to the present invention, in particular together with a tibia; [Figure 8F] 13A-13D show views of a further exemplary embodiment of a cap component according to the present invention, in particular with respect to the tibio-talar joint; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0068] FIG. 1 shows an exemplary embodiment of an endoprosthesis 30 according to the present invention having an exemplary embodiment of an insert component 10 according to the present invention for a first bone, in particular a first bone joint, and an exemplary embodiment of a cap component 20 according to the present invention for a second bone, in particular a second bone joint, where the sliding surface of the insert component 10 is in sliding contact with the sliding surface of the cap component 20.

[0069] The surface 11 of the insert component 10 facing the bone interface is partially or completely coated with a first metal or particles of a first metal. Furthermore, the insert component 10 has a convex or flat running surface.

[0070] The insert component 10 is also designed to be inserted into or to partially or completely replace an associated bone interface. The substrate 12 of the insert component 10 essentially comprises a second metal or metal alloy and / or a metal oxide or a mixture of metal oxides.

[0071] The metal oxide may include or be yttrium oxide, zirconium oxide, or aluminum oxide. Additionally or alternatively, the metal oxide mixture may include at least one metal oxide of yttrium oxide, zirconium oxide, or aluminum oxide, or may be a mixture of yttrium oxide, stabilized zirconium oxide, and aluminum oxide.

[0072] The insert component 10 of the endoprosthesis 30 illustratively has a substrate 12 that includes a mixture of yttrium stabilized zirconium oxide and aluminum oxide.

[0073] Furthermore, it is particularly advantageous if the first metal comprises titanium particles, which are preferably applied using a titanium plasma spray coating process or another thermal process. For example, the insert component 10 has such a coating 11. In particular, this is a TiCP coating.

[0074] It may also be particularly advantageous if the insert component 10 comprises at least one anti-rotation and / or anti-translation element, which is preferably arranged on the surface 11 of the insert component 10 facing the bone joint.

[0075] It should be noted that even if the exemplary embodiment 10 of the insert component according to the invention according to FIG. 1 does not explicitly show such a fixing element, the at least one anti-rotation and / or anti-translation element has the form of at least one tooth, preferably a toothed macrostructure, or at least one cavity, preferably several cavities, particularly preferably several cavities evenly distributed on the corresponding surface, very particularly preferably several golf ball-shaped cavities.

[0076] With regard to the cap component 20 of the endoprosthesis 30, it should be mentioned that the cap component 20 is designed to partially or completely surround the relevant bone joint. The cap component 20 according to the invention is therefore particularly useful for resurfacing or resurfacing the relevant bone joint. The relevant bone joint itself can typically be preserved.

[0077] Furthermore, the surface 21 of the cap component 20 facing the bone interface is partially or completely covered with the first metal or particles of the first metal. Furthermore, the substrate 22 of the cap component 20 is generally softer than the second metal and / or metal alloy, in particular the second metal and / or metal alloy of the insert component 10. The cap component 20 further comprises a convex or flat sliding surface.

[0078] Furthermore, it may be particularly advantageous if the cap component 20 and / or the substrate 22 of the cap component 20 have a stiffness, particularly a modulus of elasticity, similar to the bone material of the associated bone interface. It is also noted that the second metal may be titanium, iron, chromium, or cobalt.

[0079] Additionally or alternatively, the metal alloy may comprise at least one of the metals titanium, iron, chromium and cobalt. Furthermore, it may be particularly advantageous if the first metal comprises titanium particles, which are preferably fixed by a high-temperature or low-temperature process. For example, the cap component 20 has a coating 21 of such pure titanium. In particular, this may be a TiCP coating.

[0080] Further particular advantages arise when the substrate 22 of the cap component 20 comprises or consists of a plastic, preferably polyethylene, particularly preferably polyethylene stabilized by cross-linking, very particularly preferably polyethylene mixed with vitamin E and stabilized by cross-linking.

[0081] By way of example, the substrate 22 of the cap component 20 comprises polyethylene blended with vitamin E. Furthermore, according to Fig. 1 it can be seen that the cap component 20 has at least one anti-rotation element 23, which is preferably disposed on a surface 21 of the cap component 20 facing the bone interface.

[0082] It may also be particularly advantageous if the at least one anti-rotation element 23 has the form of a bar, a bollard, a thread, a tooth, a cross, a star or an anchor pin, in particular a peg. Additionally or alternatively, there are particular advantages if the at least one anti-rotation element 23 is arranged in a circle and / or in corresponding poles with respect to the cap component 20.

[0083] 1, it is for example a peg with a cross base, in particular made of polyethylene or made of the base material 22 of the cap component 20. Furthermore, the cap component 20 can have at least one anti-translation element, which is preferably arranged on the surface 21 of the cap component 20 facing the bone interface.

[0084] It should be noted that even if the exemplary embodiment 20 of the cap component according to the present invention according to FIG. 1 does not explicitly show such a fixing element, the at least one anti-translation element has the form of a groove, preferably an annular groove, or at least one cavity, preferably several cavities, particularly preferably several cavities evenly distributed on the corresponding surface, very particularly preferably several golf ball-shaped cavities.

[0085] Furthermore, particular advantages may arise if the at least one anti-rotation element 23 and / or the at least one anti-translation element are configured to absorb forces and / or moments immediately after the corresponding implantation and / or over time after the corresponding growth of the bone material of the associated bone joint.

[0086] It should further be noted that the cap component 20 may include at least one recess, which is preferably designed to protect a zone with a critical blood supply during corresponding preparation and / or implantation.

[0087] Also from FIG. 1, it can be seen that the shape of the cap component 20 deviates from a sphere and / or tapers on the surface facing away from the associated bone interface, particularly on the underside of the corresponding equator of the cap component 20.

[0088] In this connection, it should also be noted that the aforementioned shapes may have two or more different radii. It should also be mentioned that the shapes may additionally or alternatively be based on ellipses or freely defined curves.

[0089] It should also be mentioned that with respect to two or more radii it may be particularly advantageous if there are three radii, one of the three radii being in particular a transition radius to the other two radii.

[0090] Furthermore, certain advantages may arise if the aforementioned shape of the cap component 20 is such that it deviates from a sphere of the surface 21 facing the bone interface, especially on the underside of the corresponding equator of the cap component 20. Regarding the two different radii of shapes mentioned above, it is noted that these are further emphasized by FIG. 2 which shows only the cap component 20.

[0091] According to Fig. 2, the surface facing away from the relevant bone joint has two outer radii 25a, 25b, which can additionally or alternatively be based on three or more radii, an ellipsoid or a freely defined curve or line, the surface 21 facing the bone joint having an inner circular arc 24 which advantageously merges into a cylindrical or slightly conical part at the outlet. In particular, if the endoprosthesis 30 shown by way of example in Fig. 3 is used as a hip joint endoprosthesis, the two asterisks (*) in Fig. 2 further indicate that the two outer radii 25a, 25b are designed to achieve a femoral head-neck offset of at least 0.5 mm, preferably at least 2 mm, particularly preferably at least mm, very particularly preferably at least 5 mm.

[0092] For the sake of completeness, in the case of FIG. 3, it should be mentioned that the first bone referred to in the context of the endoprosthesis 30 is the pelvis and the first bone joint is the acetabulum, and the second bone referred to also in the context of the endoprosthesis 30 is the femur and the second bone joint is the femoral head.

[0093] FIG. 4 also shows a further advantage of the endoprosthesis 30: in particular if the above-mentioned surface replacement using the cap component 20 is not sufficient in the long term, the femur or femoral head may be replaced by a conventional implant 40 in a corresponding follow-up surgery, while at least a portion of the endoprosthesis 30, in particular the insert component 10, typically remains unchanged.

[0094] Because at least a portion of the endoprosthesis 30 does not need to be adapted or can continue to be used substantially unchanged, even in the case of follow-up surgeries, the corresponding follow-up surgeries are not only less complicated but also take less time.

[0095] A detailed cross-sectional view 50c of an exemplary embodiment of a cap component according to the invention is shown in Fig. 5A, which includes, for example, two grooves 51, which in particular run parallel to each other. Preferably, these two grooves 51 act as anti-translation means or elements and are in particular arranged in a tapered part of the cap component. The paths of the grooves are typically perpendicular or substantially perpendicular to an axis 56, or non-parallel at an angle to each other, which axis 56 in particular runs centrally or substantially centrally through a pole of the cap component.

[0096] 5A, it can be seen that the surface of the bone interface or cap component facing the inner surface is provided with a TiCP coating 53 or an osteoconductive coating. Furthermore, the cap component preferably comprises ribs 52a, 52b, 52c which act as anti-rotation means or elements and are arranged on the inner surface of the cap component. Ribs 52a and 52c each extend parallel or substantially parallel to axis 56, whereas in an exemplary embodiment rib 52b is arranged at an angle to axis 56.

[0097] It should be noted that, although ribs 52a, 52b, 52c are shown together in Fig. 50c for the sake of particular compactness, in practice ribs 52a and 52c are typically implemented together, or only one of the two aforementioned ribs or only rib 52b. In other words, in practice, the elements are generally arranged on the inner surface of the cap component such that they are inclined, parallel, or substantially parallel to axis 56.

[0098] 5A, it can be seen that all of the ribs 52a, 52b, 52c have triangular cross sections. In particular, the rib 52b has an equilateral triangular cross section, and the ribs 52a and 52c each have a right-angled triangular cross section.

[0099] In the case of the right triangle described above, the shorter catheter is preferably disposed on the inner surface of the cap component, and the two ribs 52a and 52c are oriented such that their cross sections cannot be aligned if one of the two ribs 52a and 52c is moved on the inner surface of the cap component.

[0100] Moreover, Fig. 5B shows a further view 50d of the view according to Fig. 5A. The aforementioned Fig. 50d shows in particular the already mentioned ribs 52a, 52b, 52c as well as a rib cross 54 arranged on the inner surface of the pole of the cap component. Preferably, this rib cross 54 prevents the cap component from rotating or acts as an anti-rotation element. It should be noted that the rib cross 54 is arranged in particular perpendicular or substantially perpendicular to the axis 56. This is not explicitly shown in Fig. 50d. Furthermore, the axis 56 passes in particular through the center of the rib cross 54.

[0101] It should be noted that the ribs 52a, 52b, 52c can also have other shapes or cross sections. As an example, Fig. 5C shows a further possible rib shape 50e and their cross sections 55a, 55b, 55c, 55d. According to the cross sections 55a, 55c, for example, inclined triangles inclined in different directions can be considered as suitable cross sections. Furthermore, the isosceles triangle 55b is suitable as a cross section of the rib as well as parabolic or sinusoidal cross sections.

[0102] Furthermore, FIG. 5D shows a diagram of a further exemplary embodiment 50a of a cap component according to the present invention.

[0103] This embodiment 50a corresponds substantially to that shown in FIG. 5C, it being seen that the rib cross 54 has been replaced by a pin 54a.

[0104] In this connection, the different rib shapes according to the above figures, in particular FIG. 5C, apply as well.

[0105] Figure 6A shows a detailed cross-sectional view 60a of a further exemplary embodiment of a cap component according to the present invention. It should be noted that Figures 5A, 5B, 5C and 5D already described are equally applicable to this embodiment.

[0106] It should also be pointed out that the above comments regarding shaft 56 and groove 51 apply equally to both shaft 66 and two grooves 61 shown in Figure 6A. Grooves 61 and 51 are typically annular grooves.

[0107] Furthermore, Fig. 6A shows a groove 62b arranged parallel or substantially parallel to the axis 66 on the inner surface of the cap component. The rib shape according to Fig. 5C can be applied to this groove 62b as well, in particular inverted. In this context, "inverted" means that the rib is designed as an inward element in the form of a groove.

[0108] Furthermore, the surface facing the bone interface or the inner surface of the cap component has a groove 62a arranged at an angle to the axis 66. Preferably, this groove 62a serves as an anti-rotational and / or anti-translation means or anti-rotational and / or anti-translation element. Furthermore, according to Fig. 6A it can be seen that the surface facing the bone interface or the inner surface of the cap component is provided with a coating 63, in particular a TiCP coating. Furthermore, the groove 62a, like the groove 62b, may be a rib according to Fig. 5C designed accordingly in inverted form.

[0109] Further, FIG. 6B shows a detailed cross-sectional view of a further exemplary embodiment 60c of a cap component according to the present invention, which is substantially the same as that of FIG. 6A, and further includes a golf ball-shaped structure 68 disposed on an inner surface of the cap component.

[0110] Advantageously, this golf ball-shaped structure 68 fixes the cap component, particularly against corresponding rotation and / or translation, preferably rotation, and can be replaced in its geometric configuration by other inwardly facing shapes.

[0111] Furthermore, it is particularly advantageous if the golf ball-shaped structure 68 is arranged starting above the groove 61 in the direction of the pole of the cap component and in particular extending up to the pole.

[0112] Fig. 6C shows a three-dimensional view 60b of the embodiment according to Fig. 6A, further showing a rib cross 64, the above description of which with respect to the rib cross 54 is equally applicable. Preferably, this rib cross 64 prevents rotation of the cap component or acts as an anti-rotation element. It should be noted that the rib cross 64 is in particular arranged perpendicular or substantially perpendicular to an axis 66, which is not explicitly shown in Fig. 60b. Furthermore, the axis 66 in particular passes through the center of the rib cross 64.

[0113] Similarly, FIG. 6D shows a three-dimensional view 60d of the embodiment according to FIG. 6B.

[0114] For the sake of completeness, it should be noted that rib crosses 54 and 64 differ substantially in that the leg surfaces of rib cross 54 that face the bone joint are each flat, while the leg surfaces of rib cross 64 are each directed toward the bone joint.

[0115] Figure 7A further shows a three-dimensional view 70a of an exemplary embodiment of an insert component according to the invention, where it can be seen that the surface of the insert component facing the bone interface is provided with a coating 73, preferably of pure titanium or an osteoconductive layer.

[0116] Moreover, Fig. 7B shows a three-dimensional view 70b of a further exemplary embodiment of an insert component according to the invention, which substantially corresponds to the one shown in Fig. 7A, in which the surface facing outwards towards the bone has a golf ball-shaped depression 78 or golf ball-shaped structure, which helps to prevent rotation and / or translation, especially rotation, and whose geometry can be replaced by other inwardly facing shapes.

[0117] Finally, different embodiments of a cap component according to the invention are presented below in the context of correspondingly different bones or bone joints, in order in particular to demonstrate the high flexibility of the invention.

[0118] FIG. 8A illustrates an embodiment 80a of a cap component according to the present invention for use with a humerus 90a.

[0119] On the other hand, an embodiment 80b of a cap component according to the present invention is shown in FIG. 8B for use with a femoral head 90b.

[0120] 8C further illustrates an embodiment 80c of a cap component according to the present invention for use with a talus 90c, where the cap component 80c is particularly suitable for achieving partial resurfacing, preferably at the corresponding edge region.

[0121] For the sake of completeness, it is noted that the cap component according to the invention is generally suitable for resurfacing partial joints.

[0122] The aforementioned embodiments 80a, 80b, 80c of the cap component according to the invention each have a substrate 81a, 81b, 81c made in particular of a non-metallic and non-ceramic plastic material, preferably having an elastic modulus of up to 5 GPa. The plastic material may be a polymer, for example polyethylene or PEEK.

[0123] Furthermore, the cap component embodiments 80a, 80b, 80c according to the invention each have a metal coating or doping 82a, 82b, 82c, which preferably extends at least partially on the surface of the cap component 80a, 80b, 80c facing the corresponding bone or bone interface, said coating or doping 82a, 82b, 82c may comprise titanium or calcium, in particular hydroxyapatite.

[0124] Additionally, each of the embodiments 80a, 80b, 80c specifically illustrates a pin 83a, 83b, 83c, which preferably functions as a corresponding anti-translation means.

[0125] Furthermore, Fig. 8D shows an embodiment 80d of a cap component according to the invention, specifically for use with a femoral condyle 90d. The above explanations are equally applicable to corresponding substrates or corresponding coatings or dopings.

[0126] It can also be seen that the embodiment 80d has two pins 83d, 84d, each of which is in particular circular in shape, and in particular these pins 83d, 84d serve not only to prevent a corresponding translation, but also to prevent a corresponding rotation.

[0127] Also note that the sliding surface 89d of the cap component 80d is a convex sliding surface.

[0128] However, it may also be flat or planar, as shown in particular with the tibia 90e in Fig. 8E. In addition to the flat running surface 89e, the embodiment 80e of the cap component according to the invention shown in Fig. 8E has in particular a substrate 81e, as already described above. The coating or doping 82e has also been substantially already described above and does not need to be repeated.

[0129] 8E further shows that the cap component 80e has a total of three pins 83e, 84e, 85e, which, among other things, serve not only to prevent corresponding translation but also to prevent corresponding rotation.

[0130] It is also particularly advantageous if two of the three pins have a circular shape and the third pin has an elliptical or oblong shape, for example pins 83e, 84e are circular and pin 85e is elliptical or oblong.

[0131] Finally, FIG. 8F shows a view of a further exemplary embodiment of a cap component 80f according to the present invention, in particular with a tibio-talar joint 90f.

[0132] The tibia 83f of the joint 90f has an insert component 81f in the sense of the invention with a concave bearing surface, whereas the talus 82f of the joint 90f has a cap component according to the invention with a convex bearing surface. The cap component 80f can be manufactured using the applicant's convex prior art technology, whereas the insert component 81f is preferably manufactured using the concave titanium plasma spray technology.

[0133] Additionally, from FIG. 8F it can be seen that cap component 80f preferably has pins 84f which serve as corresponding anti-translation means.

[0134] For completeness, it should also be mentioned against the background of Figures 8E and 8F, or as shown in the example of the tibia, that in some cases it may be useful to equip a particular bone or a particular bone joint with a cap component according to the present invention and in other cases with an insert component according to the present invention.

[0135] Note also that FIG. 8F further illustrates that the present invention is particularly suited for resurfacing the upper ankle joint.

[0136] The invention is not limited to the exemplary embodiments described above: all features described in the specification or claimed in the claims or shown in the drawings can be combined with one another in any way within the scope of the invention.

Claims

1. A cap component (20) for an in vivo prosthesis (30), comprising: a convex or flat sliding surface and a surface (21) facing the bone joint connection; the cap component (20) is designed to surround part or all of the bone joint connection; the cap component (20) and / or the first base material (22) of the cap component (20) has an elastic modulus substantially equal to that of the bone material of the bone joint connection; the surface (21) is at least partially coated with a first metal or particles of the first metal, the cap component (20).

2. The elastic modulus of the cap component (20) and / or the first base material (22) of the cap component (20) is less than 10 GPa, the elastic modulus of the sliding surface of the cap component (20) is substantially the same as the elastic modulus of the cap component (20) and / or the first base material (22) of the cap component (20), the cap component (20) according to claim 1.

3. the first base material (22) of the cap component (20) is softer than the second metal and / or metal alloy of the second base material (12) of the insert component (10) that slidably cooperates with the cap component (20), the second metal includes titanium, iron, chromium or cobalt, or any combination thereof, and / or, the metal alloy preferably includes titanium, iron, chromium, cobalt, or any combination thereof, the cap component (20) according to claim 1 or 2.

4. the first metal includes titanium particles, the titanium particles are applied using a titanium plasma spray coating process, the cap component (20) according to claim 1.

5. The cap component (20) according to claim 1, wherein the first base material (22) of the cap component (20) contains plastic.

6. The cap component (20) has at least one anti-rotation element (23), The cap component (20) according to claim 1, wherein the anti-rotation element (23) is arranged on the surface (21) of the cap component (20) facing the bone joint.

7. The anti-rotation element (23) is a bar, bollard, thread, tooth, cross, star or anchor pin, or any combination thereof, and / or The cap component (20) according to claim 6, wherein the anti-rotation element (23) is arranged circularly with respect to the cap component (20) and / or at the corresponding pole.

8. The cap component (20) according to claim 6 or 7, wherein the cap component (20) has a translation prevention element arranged on the surface (21) of the cap component (20) facing the bone joint.

9. The cap component (20) according to claim 8, wherein the translation prevention element has a groove or an annular groove.

10. The cap component (20) according to claim 8, wherein the anti-rotation element (23) and the translation prevention element are set to absorb force and / or moment over the corresponding time immediately after transplantation and / or after the growth of the bone material at the bone joint connection.

11. The cap component (20) has a recess, The cap component (20) according to claim 1, wherein the recess is designed to protect a zone involving important blood supply during the corresponding preparation and / or transplantation.

12. The sliding surface of the cap component (20) is spherical on the first surface of the equator of the cap component (20) and deviates from a sphere and / or tapers on the second surface of the equator of the cap component (20), the cap component (20) according to claim 1.

13. The sliding surface of the cap component (20) has two different radii and / or The sliding surface of the cap component (20) is based on an ellipse or a freely defined curve or line, whereby a femoral head-neck offset of at least 0.5 mm is achieved, the cap component (20) according to claim 12.

14. The surface (21) of the cap component (20) is spherical on the first surface of the equator of the cap component (20) and deviates from a sphere on the second surface of the equator of the cap component (20), the cap component (20) according to claim 1.

15. An insert component (10) for a first bone joint of a first bone having a sliding surface and a cap component (20) for a second bone joint of a second bone, wherein the cap component (20) has a sliding surface, is designed to surround part or all of the second bone joint connection, the cap component (20) and / or the first base material (22) of the cap component (20) has an elastic modulus substantially equal to that of the bone material of the bone joint connection, the surface (21) of the cap component (20) facing the second bone joint is at least partially coated with a first metal or particles of the first metal, the sliding surface of the insert component (10) is in sliding contact with the sliding surface of the cap component (20), an in-vivo prosthesis (30).

16. The insert component (10) is designed to be inserted into the first bone joint or to partially or completely replace the first bone joint, and / or The surface (11) of the insert component (10) facing the first bone joint is partially or completely coated with a first metal or particles of a first metal, and / or The prosthetic implant (30) according to claim 15, wherein the second substrate (12) of the insert component (10) comprises a second metal or metal alloy and / or a metal oxide or metal oxide mixture.

17. The metal oxide comprises yttrium oxide, zirconium oxide or aluminum oxide, and / or The prosthetic implant (30) according to claim 15, wherein the first substrate (22) of the cap component (20) is softer than the second metal and / or the metal alloy of the insert component (10).

18. The second metal of the insert component (10) contains titanium particles, The prosthetic implant (30) according to claim 16, wherein the titanium particles are applied using a titanium plasma spray coating process.

19. The insert component (10) has anti-rotation and / or anti-translation elements, The prosthetic implant (30) according to claim 15, wherein the anti-rotation and / or anti-translation elements are arranged on the surface (11) of the insert component (10) facing the first bone joint.

20. The anti-rotation and / or anti-translation elements of the insert component (10) have the form of teeth or cavities, the prosthetic implant (30) according to claim 18.

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