Knee joint endoprosthesis set, patient knee joint endoprosthesis set, and knee joint endoprosthesis system

Abstract

In order to improve a knee joint endoprosthesis set for replacing a patient's knee joint, which includes a knee joint endoprosthesis having a femoral component, a tibial component, and a meniscal component, to increase the surgeon's flexibility when implanting the knee joint endoprosthesis, it is proposed that the knee joint endoprosthesis set includes an additional meniscal component, the two meniscal components being configured differently, and one of the two meniscal components being positioned between the femoral component and the tibial component cooperating with the femoral component to form the knee joint endoprosthesis. Additionally, a patient knee endoprosthesis set and an improved knee endoprosthesis system are proposed.

Description

[Technical Field]

[0001] The present invention relates to a knee endoprosthesis set for replacing a patient's knee joint, the knee endoprosthesis including a femoral component, a tibial component, and a meniscal component.

[0002] The present invention further relates to a patient knee endoprosthesis set for replacing any of the patient's two knee joints.

[0003] The present invention further relates to a knee endoprosthesis system comprising at least one knee endoprosthesis set for replacing a knee joint of a patient. [Background technology]

[0004] Knee endoprostheses are typically implanted in patients whose natural knee joint has been so severely damaged by wear and trauma that the patient's mobility is severely limited and they are often unable to place significant strain on the knee joint without taking strong painkillers.

[0005] As described above, a knee joint endoprosthesis typically includes a femoral component that is fixed to a correspondingly prepared femur after resection of the natural knee joint, a tibial component that is fixed to a correspondingly prepared tibia, and a meniscal component that is disposed between the femoral and tibial components. The meniscal component cooperates with the femoral component to form a sliding pair. When the knee joint endoprosthesis that forms the artificial knee joint is bent, the femoral component and the meniscal component slide against each other on their contact surfaces.

[0006] Furthermore, it is known that in some patients, the femur moves medially relative to the tibia much less than it moves laterally relative to the tibia during knee movement. This causes the femur's axis of rotation in the longitudinal direction of the leg to be more medial relative to the tibia. This is also known as the "medial pivot." Knee endoprostheses designed with this "medial pivot" are used to replace damaged natural knee joints with this movement pattern.

[0007] Furthermore, research has shown that some patients have a kinematic pattern in which the femur moves significantly less outward than inward relative to the tibia during knee movement. This is also known as a "lateral pivot." Correspondingly, the axis of rotation of the femur relative to the length of the leg is more lateral to the tibia. To treat this kinematic pattern, knee endoprostheses exist that accommodate this "lateral pivot" design. Summary of the Invention

[0008] Two complete knee endoprostheses (including two fully equipped instrument sets) must be provided so that the surgeon can freely decide which type of knee prosthesis to use, for example, an "internal pivot" or "lateral pivot" design, even after the damaged knee is removed. Therefore, two complete knee endoprostheses include at least six components: two femoral components, two meniscal components, and two tibial components of the required sizes. These, along with all instruments and test implants, must be provided in their entirety for the surgical procedure. If unused and still in their sterile packaging, they can be used in a subsequent surgical procedure. However, the test implants and instruments corresponding to the unused components must be carefully reprocessed before reuse.

[0009] It is therefore an object of the present invention to improve knee endoprosthesis sets, patient knee endoprosthesis sets, and knee endoprosthesis systems of the type described above, to provide greater flexibility to surgeons when implanting knee endoprostheses.

[0010] According to the invention, this object is achieved in a knee joint endoprosthesis set of the above-mentioned kind in that the knee joint endoprosthesis comprises a further meniscal component, the two meniscal components being constructed differently, and one of the two meniscal components being positioned between the femoral component and the cooperating tibial component to form the knee joint endoprosthesis.

[0011] Further development of the knee endoprosthesis set of the type proposed at the outset offers the advantage that, in particular, it is not necessary to provide two complete knee endoprostheses, including all the associated instruments and test implants, to achieve different movement patterns. Instead, it is necessary to provide only four components: one femoral component, one tibial component, and two meniscal components. Different movement patterns of the implanted prosthetic knee, i.e., knee endoprosthesis, can be achieved by selectively using one or the other meniscal component. By "selectively," we mean that only one of the two meniscal components, i.e., only one, is positioned between the tibial and femoral components to form the knee endoprosthesis. This has the advantage, as mentioned above, of providing only four components for surgery, ensuring the surgeon complete freedom and flexibility during the surgical procedure, especially after the bone has been sawed or shaped. This is not possible with currently available knee endoprosthesis systems. This is because, until now, when a surgeon determined the shape of the knee and prepared the bone accordingly, they no longer had the option of switching to a different knee endoprosthesis system without removing additional healthy bone. The proposed further developed knee endoprosthesis set requires fewer components, which significantly reduces expenditures on the manufacture of the knee endoprosthesis set and the reprocessing of unused components. The proposed further developed knee endoprosthesis set therefore requires two fewer absolutely necessary components. This represents a one-third reduction compared to two fully usable knee endoprostheses, each dedicated to a single movement pattern (e.g., the movement patterns corresponding to the "medial pivot" and "lateral pivot" mentioned at the beginning).To achieve these movement patterns, it is particularly advantageous if the two meniscal components, i.e., the two meniscal components independently selected to form the knee joint endoprosthesis and positioned between the tibial and femoral components, can be immobilized relative to the tibial component. Therefore, such knee joint endoprostheses have so-called "fixed-bearing" meniscal components that are immobilely held on the tibial component after implantation. This knee joint endoprosthesis is thus a "fixed-bearing" type. In such prosthesis types, the selected meniscal component is immobilely attached to the tibial component, so only direct or rapid relative movement between the femoral component and the selected meniscal component is possible.

[0012] A knee joint endoprosthesis set preferably includes a single (only one) femoral component and a single (only one) tibial component. Therefore, the number of components included in the knee joint endoprosthesis set may be limited to a total of four components: a single femoral component, a single tibial component, and two different meniscal components. As already explained, these two different meniscal components allow this four-component knee joint endoprosthesis set to achieve two different movement patterns of the knee joint endoprosthesis, especially if it is of the "fixed bearing" type. This is achieved by appropriately selecting the meniscal components.

[0013] Advantageously, a knee endoprosthesis set includes only two meniscal components. Therefore, as mentioned above, the number of components in a knee endoprosthesis set can be limited to a total of four. Nevertheless, with two different meniscal components, it is possible to realize two different kinematic patterns of the knee endoprosthesis. In particular, even after cutting the femoral and / or tibial bones and evaluating the joint situation with appropriate test components, it is possible to select or change the kinematics without additional bone work or reworking. This is possible by simply replacing (exchanging) the meniscal components. In particular, in combination with test components, different meniscal components can even be compared with each other intraoperatively.

[0014] To further simplify the setup of the knee joint endoprosthesis set, it is advantageous for the two meniscal components to be configured mirror-symmetrically with respect to a first mirror plane extending in the longitudinal direction of the prosthesis. In other words, one meniscal component can be transformed into the other meniscal component by mirroring it on the first mirror plane. This is particularly possible even when the two meniscal components are not mirror-symmetrical when viewed individually. The proposed configuration of the two meniscal components minimizes design effort, particularly because the shape of one meniscal component can be transferred to the other meniscal component by mirroring it on the first mirror plane.

[0015] It is desirable for a knee joint endoprosthesis set to include a coupling device for coupling a tibial component and two meniscal components in a coupling position, the coupling device having a mirror-symmetrical configuration with respect to a coupling device mirror plane extending in the longitudinal direction of the prosthesis. Such a design has the advantage, in particular, that both meniscal components can be selectively coupled to the same tibial component by the mirror-symmetrically configured coupling device. Therefore, in principle, it is sufficient to provide a single tibial component, which can be selectively coupled to each of the two meniscal components of the knee joint endoprosthesis set in a defined manner to form a complete knee joint endoprosthesis. Furthermore, a mirror-symmetrically configured coupling device has the advantage of requiring less design effort. The longitudinal direction of the prosthesis may be defined, in particular, by the longitudinal axis of the leg when the knee joint endoprosthesis is in an extended position. The knee endoprosthesis is in an extended position, i.e., when the patient's lower leg, on which the tibial component is placed, and the patient's upper leg, on which the femoral component is placed, are in extension, as when, for example, the patient stands or lies with the knee fully extended, i.e., with the leg entirely extended. The coupling device mirror plane may also extend parallel to the patient's median plane. The median plane may therefore be, for example, a plane spanned by the longitudinal axis of the leg on the one hand and an axis extending in the anterior-posterior direction.

[0016] It is advantageous to form a knee joint endoprosthesis in which the tibial component and one of the two meniscal components are joined together in a joining position so that said one of the two meniscal components is held immovably on the tibial component. This further development makes it possible, in particular, to obtain knee joint endoprostheses of the so-called "fixed-bearing" type, i.e., knee joint endoprostheses in which, after implantation, the meniscal component is held immovably on the tibial component, in particular in a plane extending transverse to the longitudinal direction of the prosthesis.

[0017] Preferably, the coupling device includes two first coupling portions and one second coupling portion, one of which is disposed or formed on each of the two meniscal components and the other of which is disposed or formed on the tibial component, and the first coupling portion and the second coupling portion of one of the two meniscal components engage with each other in a force-locking and / or positive-locking manner in the coupled position and disengage in the separated position. Such a coupling device allows a defined connection between the tibial component and a selected one of the two meniscal components to be achieved in a simple manner. In particular, a surgeon can change the desired motion pattern of the knee joint endoprosthesis by replacing the meniscal component, even during surgery.

[0018] If the first connecting portion has a mirror-symmetrical configuration with respect to the connecting device mirror surface, the knee joint endoprosthesis set can be manufactured with a simple structure.

[0019] The second coupling portion is preferably a mirror image of the coupling device mirror plane, which allows, on the one hand, to minimize the design effort of the knee joint endoprosthesis set, and, on the other hand, to optimize coupling to the corresponding first coupling portion (which is also a mirror image of the coupling device mirror plane).

[0020] According to a further preferred embodiment of the present invention, the femoral component may include a condylar portion having a medial condyle and a lateral condyle, and each of the two meniscal components may include a meniscal component bearing surface. The meniscal component bearing surfaces are surfaces that cooperate with the two condyles at a medial sliding face region and a lateral sliding face region. The medial condyle and the medial sliding face region may form a medial sliding pair, and the lateral condyle and the lateral sliding face region may form a lateral sliding pair. Using the knee joint endoprosthesis set formed as described above allows for the formation of a knee joint endoprosthesis in which the femoral component can cooperate with each of the two meniscal components in a desired and defined manner. In particular, different configurations of the meniscal components, such as the meniscal component bearing surfaces, may enable different movement patterns of the knee joint endoprosthesis when the femoral component cooperates with one or the other meniscal component.

[0021] The shapes and / or sizes of the medial and lateral bearing surface regions are preferably different from one another. Depending on the shape and size of the bearing surface regions of the meniscal component bearing surface, different movement patterns can be realized in a defined manner in the knee joint endoprosthesis. This is realized, in particular, by presetting the shape of each bearing surface region, which, in cooperation with the respective femoral condyle, allows, in particular, a rolling movement only, a sliding movement only, or a combination of rolling and sliding movements.

[0022] The condyles of the femoral component are preferably mirror-symmetric with respect to the femoral component mirror surface extending in the longitudinal direction of the prosthesis. This design allows, in particular, the medial and lateral condyles of the femoral component to be mirror-symmetric. This has the advantage, in particular, that the movement pattern of the knee joint endoprosthesis, which can be formed using the knee joint endoprosthesis set, can be predetermined exclusively by the meniscal component bearing surfaces. Therefore, in particular, it is possible to change the movement pattern of the knee joint endoprosthesis by replacing one meniscal component with another.

[0023] The construction of the knee joint endoprosthesis set can be simplified, in particular, by the coupling device mirror surface defining the femoral component mirror surface. Alternatively, the coupling device mirror surface and the femoral component mirror surface can extend parallel to each other. In this case, for example, an offset of the two condyles of the femoral component relative to the tibial component can be achieved when, in the implanted position of the knee joint endoprosthesis, the two mirror surfaces do not coincide but are instead offset parallel to each other.

[0024] The medial condyle and medial bearing surface area define the medial joint area, and the lateral condyle and lateral bearing surface area define the lateral joint area, with one of the two joint areas having a higher degree of conformity between the condyle and the associated bearing surface area than the other joint area. As a result of this design, it is possible to realize different movement patterns of the knee joint endoprosthesis, among other things. For example, in areas of high conformity, a preferred or substantially preferred rotation about a center of rotation may be predetermined, while in joint areas of low conformity, a sliding or overlapping sliding / rolling movement of the femoral component and the associated meniscal component may be predetermined. The greater the conformity in each joint area, the better the guidance and positioning of the femoral component and the meniscal component relative to each other in that joint area.

[0025] The joint region with a higher degree of congruence preferably defines a ball-jointed joint region or a substantially ball-jointed joint region. This has the advantage, in particular, that the femoral component can be rotated relative to the meniscal component around the ball-jointed joint region, even in an extended position of the knee, thereby enabling rotation of the femoral component substantially around the longitudinal axis of the patient's leg. Depending on whether the ball-jointed joint region is located on the medial or lateral side of the knee endoprosthesis, for example, depending on whether one or the other meniscal component is used, a corresponding knee endoprosthesis of, in particular, an "internal pivot" or "lateral pivot" design can be realized. The surgeon can make the appropriate choice even during the surgical procedure.

[0026] According to a further preferred embodiment of the present invention, the meniscal component of the knee joint endoprosthesis may comprise a first connection portion for connection with the tibial component, particularly for immobilization, and meniscal component bearing surfaces that cooperate with the femoral component in the medial and lateral bearing surface regions. The first connection portion may have a mirror-symmetrical configuration relative to the mirror-symmetrical configuration of the connection portion, and the bearing surface regions may have an asymmetrical configuration relative to the mirror-symmetrical configuration of the connection portion. This configuration may also be provided, in particular, in a knee joint endoprosthesis set of the above-mentioned type. The proposed further development particularly simplifies the design of the knee joint endoprosthesis set, since the symmetrical configuration of the first connection portion allows any combination with a tibial component having a correspondingly configured, i.e., mirror-symmetrical, second connection portion. In contrast, the two bearing surface regions may be asymmetrically configured relative to each other, thereby enabling corresponding movement patterns in the knee joint endoprosthesis, for example, according to an "internal pivot" design or an "external pivot" design. In order to achieve these movement patterns, it is particularly advantageous, as described in detail above, if the two meniscal components, i.e., the two meniscal components that are independently selected and placed between the tibial and femoral components to form the knee joint endoprosthesis, can be immovably fixed to the tibial component to achieve a "fixed bearing" type knee joint endoprosthesis.

[0027] The shapes and / or sizes of the medial and lateral bearing surface areas are preferably different from each other, and by presetting the shapes and / or sizes of the bearing surface areas, it is possible to predefine specific movement patterns, particularly during flexion of the knee endoprosthesis.

[0028] The above-mentioned objects are further achieved by a knee joint endoprosthesis set for a patient for replacing any one of two knee joints of a patient, the knee joint endoprosthesis set for a patient comprising one of the knee joint endoprosthesis sets described above and a further femoral component, one of the two femoral components being configured in the form of a left femoral component and the other of the two femoral components being configured in the form of a right femoral component.

[0029] According to the proposed configuration of a patient knee endoprosthesis set, a knee endoprosthesis can be configured with two femoral components, two meniscal components, and a tibial component, specifically for the left and right knees. This knee endoprosthesis can be implanted to replace one of a patient's knees. This five-component knee endoprosthesis set is one less component than a knee endoprosthesis, which requires providing at least three components for each knee even if the decision is made whether to use an "internal pivot" or "external pivot" design for each knee. Conventional knee endoprosthesis systems require providing at least 12 components if the decision to use an "internal pivot" or "external pivot" design is not made until intraoperatively. Therefore, a knee endoprosthesis with an "internal pivot" design requires at least three components for both the left and right knees. Similarly, a knee endoprosthesis of the "external pivot" design requires at least three components for both the left and right knees. In accordance with the present invention, as discussed above, this requirement requires only five components.

[0030] The two femoral components and the two meniscal components are advantageously configured to be interoperable with one another as desired. "Interoperable with one another as desired" in this context particularly means that each femoral component can be selectively combined with two meniscal components. Thus, a total of four combinations can be achieved with this patient knee endoprosthesis set. For example, both "medial pivot" and "lateral pivot" designs can be realized for knee joints replacing the left and right knees, respectively. In particular, if the decision on whether to stabilize the "medial" or "lateral" side of a patient's knee joint needs to be reserved until the very last moment before surgery, this patient knee joint set has the advantage of actually being able to reserve this decision until the very last moment. In other words, the kinematic characteristics of the knee joint can be adapted until the very end of surgery, regardless of whether the left knee or the right knee is operated on first. Due to the symmetry of the system, the surgeon need only be provided with the components necessary to form both knee endoprostheses. This is possible if at least two femoral components, two tibial components, and a meniscal component are available. Because the meniscal components for right and left knees are interchangeable, such a system allows the surgeon to support either a "lateral pivot" or a "medial pivot" design in either the left or right knee, depending on the combination.

[0031] It is desirable that the two femoral components be mirror-symmetrical with respect to a second mirror plane extending longitudinally of the prosthesis. This means, in particular, that one femoral component can be transformed into the other femoral component by mirroring it on the second mirror plane. This minimizes the design effort required to create a knee joint endoprosthesis set for a patient.

[0032] The first mirror plane preferably defines a second mirror plane. Thus, in particular, the two femoral components and the two meniscal components can be configured with mirror symmetry with respect to the first and second mirror planes in the manner described above. Thus, a femoral component cooperating with one meniscal component can be transformed into the other femoral component and the other meniscal component cooperating therewith by mirroring it on one of the two mirror planes.

[0033] The knee joint endoprosthesis set for a patient advantageously includes an additional tibial component. Such a knee joint endoprosthesis set for a patient therefore includes, in particular, two tibial components, two femoral components, and two meniscal components. In particular, the two meniscal components can be selectively coupled to the tibial component as described above. This allows, for example, a total of two knee joint prostheses to be formed, but the specific design, i.e., the "medial pivot" or "lateral pivot," can still be selected during implantation (implantation), i.e., by swapping the corresponding two meniscal components.

[0034] To minimize the manufacturing costs of a patient knee endoprosthesis set, it is desirable for the tibial component and the additional tibial component included in the knee endoprosthesis set to be identical in configuration. Such a tibial component can be selectively fixed to the patient's left or right tibia. Therefore, as described above, in principle, a patient knee endoprosthesis set only needs to include three components: a femoral component, a meniscal component, and a tibial component. As described above, the femoral component and the meniscal component can be converted into corresponding components for the other knee by, for example, mirroring them once on a mirror surface, resulting in a total of five different components.

[0035] The above-mentioned object is further achieved by a knee joint endoprosthesis system comprising at least one of the above-mentioned knee joint endoprosthesis sets or at least one of the above-mentioned patient knee joint endoprosthesis sets.

[0036] Such knee endoprosthesis systems may include two, three, or more knee endoprosthesis sets or patient knee endoprosthesis sets, which may be made of different materials, for example. In particular, in preparation for implantation of the knee endoprosthesis, the surgeon can select from such knee endoprosthesis systems the components that best fit the patient, particularly in terms of size.

[0037] Advantageously, a knee joint endoprosthesis system includes at least two knee joint endoprosthesis sets, each of which has a different shape and / or size for the femoral component, two meniscal components, and / or a tibial component. This knee joint endoprosthesis system allows for the creation of knee joint endoprostheses with different shapes and kinematic designs, particularly for providing appropriate prostheses for patients of different sizes. For example, this knee joint endoprosthesis system allows for the implantation of a knee joint endoprosthesis with a kinematic pattern that matches the natural kinematic pattern of the patient's replaced knee joint.

[0038] The following description of the preferred embodiment is provided in conjunction with the drawings for further explanation. [Brief explanation of the drawings]

[0039] [Figure 1] 1 is an exploded view of a first embodiment of a knee joint endoprosthesis set. FIG. [Figure 2] FIG. 10 is an exploded view of a further embodiment of a knee joint endoprosthesis set. [Figure 3]2 is a schematic diagram of the knee joint endoprosthesis set of FIG. 1 combining two different meniscal components. [Figure 4] FIG. 4 is a perspective view of the combination shown on the left side of FIG. 3. [Figure 5] FIG. 2 is a front view of the femoral component. [Figure 6] FIG. 6 is a side view of the femoral component of FIG. 5. [Figure 7] FIG. 6 is a further view of the femoral component of FIG. 5. [Figure 8] 8 is a view similar to FIG. 7 of a further embodiment of a femoral component. [Figure 9] FIG. 5 is a side view of the tibial component of FIGS. [Figure 10] FIG. 10 is a plan view of the tibial component of FIG. 9. [Figure 11] FIG. 2 is a side view of the meniscal component shown on the left side of FIG. 1. [Figure 12] FIG. 12 is a plan view of the meniscal component of FIG. 11. [Figure 13] FIG. 13 is a cross-sectional view taken along line 13-13 in FIG. [Figure 14] FIG. 14 is a cross-sectional view taken along line 14-14 of FIG. [Figure 15] FIG. 15 is a cross-sectional view taken along line 15-15 of FIG. [Figure 16] FIG. 2 is a side view of the meniscal component shown on the right side of FIG. 1. [Figure 17] FIG. 17 is a plan view of the meniscal component of FIG. 16. DETAILED DESCRIPTION OF THE INVENTION

[0040] One embodiment of a knee endoprosthesis set 10 is shown schematically in Figure 1. The set forms part of a knee endoprosthesis system 12.

[0041] The knee endoprosthesis set 10 serves to replace a damaged knee joint in a patient. The knee endoprosthesis set 10 includes a knee endoprosthesis 14 having a femoral component 16, a tibial component 18, and two meniscal components 20, 22.

[0042] The two meniscal components 20, 22 are configured differently. To form the knee joint endoprosthesis 14, one of the two meniscal components 20, 22 is positioned between and cooperates with the femoral component 16 and the tibial component 18.

[0043] The knee joint endoprosthesis set 10 includes only one femoral component 16 and only one tibial component 18. The knee joint endoprosthesis set 10 further includes only two meniscal components 20, 22.

[0044] The two meniscal components 20, 22 are configured to be mirror images of each other with respect to a first mirror plane 26 extending in the prosthesis longitudinal direction 24. The prosthesis longitudinal direction is defined by the longitudinal axis of the leg, and in particular, by the longitudinal axis of the patient's tibia 28 in which the tibial component 18 is positioned. The shank 30 of the tibial component 18 extends parallel or substantially parallel to the prosthesis longitudinal direction 24.

[0045] The above-mentioned mirror-symmetric configuration of the two meniscal components 20, 22 means that, in particular, by reflection on the first mirror surface 26, the meniscal component 20 can be transformed into the meniscal component 22, or vice versa.

[0046] The femoral component 16 is configured to be fixed to a patient's prepared femur 32 .

[0047] The knee joint endoprosthesis set 10 includes a joining device 34 for joining the tibial component 18 and the meniscal component 20 or 22 in a joining position, which is shown diagrammatically in FIG.

[0048] In the bonded position, one of the two meniscal components 20, 22 is fixedly bonded to the tibial component, thus forming a "fixed bearing" type of knee prosthesis.

[0049] The coupling device 34 is configured to be mirror-symmetric about a coupling device mirror plane 36 that extends in the longitudinal direction 24 of the prosthesis.

[0050] The joining device 34 comprises two first joining portions 38 and one second joining portion 40. The two first joining portions 38 are each disposed or formed on one of the two meniscal components 20, 22. They are configured in the form of flat, kidney-shaped projections 44 that, in the joining position, engage in a corresponding recess 46 in the tibial component 18 in a positive-locking manner.

[0051] The recess 46 defines a planar base surface 48. The base surface 48 extends transversely, i.e., perpendicular to the prosthesis longitudinal direction 24 and faces in a direction toward the meniscal component 20 or 22.

[0052] Figure 1 shows a schematic representation of the knee joint endoprosthesis set 10 with the mating portions 38, 40 disengaged. The lower region of Figure 3 shows a schematic representation of the mating positions of the two meniscal components 20, 22. Each of the meniscal components 20, 22 is mated with one of two identically configured tibial components 18.

[0053] As previously described, the coupling device 34 is a mirror image of the coupling device mirror surface 36. Similarly, the coupling portions 38, 40 are a mirror image of the coupling device mirror surface 36. This allows the tibial component to be coupled to both the meniscal component 20 and the meniscal component 22. Which of the two meniscal components 20, 22 is used to form the knee endoprosthesis 14 depends, among other things, on the motion patterns to be replicated with the knee endoprosthesis 14, as will be described in more detail below.

[0054] 1 and 3 show a femoral component 16 configured in the form of a left femoral component 50. A right femoral component 52 is shown diagrammatically in particular in FIGS.

[0055] The femoral component 16 includes a condyle portion 54 having a medial condyle 56 and a lateral condyle 58. Each of the two condyles 56, 58 has a coronal outer surface 60. The outer surface 60 is spherical in at least some areas.

[0056] The condyles 56 , 58 are separated from one another by a notch 62 .

[0057] The condyles 54 of the femoral component 16 are mirror images of a femoral component mirror surface 64 extending in the longitudinal direction 24 of the prosthesis.

[0058] In the illustrated embodiment, the coupling device mirror surface 36 defines a femoral component mirror surface 64 .

[0059] Each of the two meniscal components 20, 22 defines a respective meniscal component bearing surface 66, 68. Each meniscal component bearing surface 66, 68 has a respective inner bearing surface region 70, 72 and a respective outer bearing surface region 74, 76.

[0060] The knee joint endoprosthesis set 10 is configured so that the medial condyle 56 forms a medial sliding pair 78 or 80 with one of the two medial bearing surface regions 70, 72. The lateral condyle 58 forms a lateral sliding pair 82 or 84 with one of the lateral bearing surface regions 74, 76. The association of the condyles 56, 58 with the bearing surface regions 70, 72 is shown diagrammatically in FIG. 3 by double arrows representing the sliding pairs 78, 80 and 82, 84.

[0061] At this point, it should be noted that in Figures 1-4, the tibia 28 and associated tibial component 18 are depicted rotated 180° relative to the femur 32 and associated femoral component 16 and associated femoral components 50, 52 relative to the longitudinal direction of the prosthesis. Thus, in these figures, the tibia 28 and associated tibial component 18 are depicted from a posterior perspective, while the femur 32 and associated femoral component 16 and associated femoral components 50, 52 are depicted from an anterior perspective. This allows for a better visualization of the meniscal component bearing surfaces 66, 68 of the meniscal components 20, 22. As discussed above in connection with Figure 3, the transverse relationship of the bearing surface regions 70, 72 to the condyles 56, 58 remains the same in the schematic representations of Figures 1, 2, and 4.

[0062] In the embodiment of the knee joint endoprosthesis set 10 shown in Figure 1, the medial bearing surface region 70 and the lateral bearing surface region 74 of the meniscal component 20 differ in shape and size. Additionally, the medial bearing surface region 72 and the lateral bearing surface region 76 differ in shape and size.

[0063] The medial condyle 56 and the medial bearing surface region 70 of the meniscal component 20 define a medial joint region 86. The lateral condyle 58 and the lateral bearing surface region 74 define a lateral joint region 88.

[0064] In one of the two joint areas 86, 88 there is a greater degree of conformity between the condyle 56 or 58 and the associated bearing surface area 70 or 74 than in the other joint area.

[0065] In the embodiment shown in FIG. 1 , the degree of conformity between the medial bearing surface region 70 and the medial condyle 56 is greater than the degree of conformity between the lateral condyle 58 and the lateral bearing surface region 74. When the meniscal component 20 is combined with the femoral component 16 in the form of the left femoral component 50 and the tibial component 18 to form the knee joint endoprosthesis 14, a movement pattern according to a “medial pivot” design can be realized. The meniscal component 20 is thereby immobilely held on the tibial component 18. In particular, relative movement of the meniscal component 20 with respect to the tibial component 18 is not permitted in a plane extending perpendicular to the longitudinal direction 24 of the prosthesis. Therefore, the knee joint endoprosthesis 14 is of the “fixed bearing” type.

[0066] When the left femoral component 50 is combined with the meniscal component 22, the degree of conformity between the lateral condyle 58 and the lateral bearing surface region 76 is greater than the degree of conformity between the medial condyle 56 and the medial bearing surface region 72. The knee joint endoprosthesis 14, including the left femoral component 50, the meniscal component 22, and the tibial component 18, is therefore suitable for defining a movement pattern according to an "external pivot" design. Even in this case, the meniscal component 22 is held immobile on the tibial component 18. In particular, the meniscal component 22 cannot move relative to the tibial component 18 in a plane extending perpendicular to the longitudinal direction 24 of the prosthesis. Therefore, the knee joint endoprosthesis 14 is still of the "fixed-bearing" type.

[0067] In the embodiment described herein, the joint regions 86, 88 having the higher degree of conformity define ball joint or substantially ball joint type joint regions.

[0068] FIG. 2 schematically illustrates a knee endoprosthesis set 10 in which the femoral component 16 is configured in the form of a right femoral component 52. The two meniscal components 20, 22 are identical to the meniscal components 20, 22 of the embodiment of the knee endoprosthesis set 10 having the left femoral component 50 shown in FIG. 1. When the right femoral component 52 is combined with the meniscal component 22, the knee endoprosthesis 14 achieves an "internal pivot" type of motion pattern. On the other hand, when the meniscal component 20 is used, the knee endoprosthesis 14 for replacing the patient's right knee joint can achieve an "external pivot" type of motion pattern. In either case, the meniscal components 20, 22 are held immobile by the tibial component 18. The resulting knee endoprosthesis 14 is of the "fixed bearing" type.

[0069] In the embodiment described herein, the meniscus components 20, 22 are configured such that the first connecting portion 38 is configured in a mirror-symmetric configuration with respect to the connecting portion mirror surface 36, and the two bearing surface regions 70, 74 on one side of the meniscus components 20, 22 and the two bearing surface regions 72, 76 on the other side are configured in an asymmetric configuration with respect to the connecting portion mirror surface 36.

[0070] In this manner, the motion pattern of the knee joint endoprosthesis 14 is preset simply by cooperating the meniscal components 20, 22, each having an asymmetrical meniscal component bearing surface 66, 68 as described above, with the femoral component 16, having the condyles 54 configured mirror-symmetrically with respect to the femoral component mirror surface 64. This allows the surgeon to instantly change the motion pattern for the knee, even during surgery, by exchanging the meniscal components 20, 22.

[0071] Predefinition of different motion patterns is possible for both the knee endoprosthesis 14 for left knee replacement and the knee endoprosthesis for right knee replacement because the condyles 54 of both the left femoral component 50 and the right femoral component 52 are identical in configuration, and in particular each is a mirror image of itself relative to the femoral component mirror surface 64.

[0072] The embodiment of knee endoprosthesis set 10 shown in Figures 1 and 2 forms part of a patient knee endoprosthesis set 90 for replacing any of the patient's two knee joints.

[0073] The patient knee endoprosthesis set 90 includes, for example, the knee endoprosthesis set 10 shown in Figure 1 and further includes a right femoral component 52. Thus, one of the two femoral components 16 of the patient knee endoprosthesis set 90 is configured in the form of a left femoral component 50, and the other is configured in the form of a right femoral component 52.

[0074] 1 and 2, the two femoral components 16, i.e., the left femoral component 50 and the right femoral component 52, can be combined with the two meniscal components 20, 22 as desired. Thus, both right and left knee joints can be formed, i.e., for example, both "medial pivot" and "lateral pivot" types can be formed.

[0075] As described, the patient knee endoprosthesis set 90 includes two femoral components 16, i.e., a left femoral component 50 and a right femoral component 52, a single tibial component 18, and two meniscal components 20, 22, for a total of five components.

[0076] The two femoral components 16 are configured to be mirror images of each other with respect to a second mirror plane 92 extending in the longitudinal direction 24 of the prosthesis. The mirror plane 92 is shown between the two femoral components 50, 52 in Figures 7 and 8. That is, the left femoral component 50 can be transformed into the right femoral component 52 by mirroring at the second mirror plane 92.

[0077] In the illustrated embodiment, the first mirror surface 26 defines the second mirror surface 92. This means that the knee endoprosthesis 14 formed by the left femoral component 50, meniscal component 20, and tibial component 18 can be transformed into a second knee endoprosthesis 14 by reflection at the first mirror surface 26 or the second mirror surface 92. The second knee endoprosthesis 14 is formed by the right femoral component 52, meniscal component 22, and tibial component 18.

[0078] In a further embodiment, the patient knee endoprosthesis set 90 includes an additional tibial component 18. The tibial component 18 may be used for both the patient's left and right tibias. Thus, both tibial components 18 have the same configuration.

[0079] The knee endoprosthesis system 12, as described, includes at least one knee endoprosthesis set 10. Alternatively, the knee endoprosthesis system 12 includes a patient knee endoprosthesis set 90.

[0080] The patient knee endoprosthesis set 90 allows a surgeon to replace one of a patient's two knees with the knee endoprosthesis 14. The surgeon has all the components necessary to replace both the right and left knees and also has the option to pre-configure the kinematic pattern of the prosthetic knee as desired (i.e., by selecting one of the two meniscal components 20, 22).

[0081] In a further embodiment, the knee endoprosthesis system 12 includes two or more sets of knee endoprostheses 10. The shapes and / or sizes of the femoral and meniscal components 16, 20, 22, and the tibial component 18 in the two or more sets of knee endoprostheses 10 are different from one another. This allows the surgeon to select the femoral and tibial components from the knee endoprosthesis system 12 that best fit the patient in terms of size, as well as the appropriate meniscal component, taking into account the desired movement pattern.

[0082] In particular, the described embodiment of the knee joint endoprosthesis set 10 allows the surgeon to flexibly respond to requirements, particularly regarding the shape and size of the femoral component 16 and the tibial component 18, even during the surgical procedure for implanting the knee joint endoprosthesis 14. Furthermore, the surgeon can quickly (instantly) pre-set the desired movement pattern of the knee joint endoprosthesis 14 by appropriately selecting one of the two meniscal components 20, 22. [Explanation of symbols]

[0083] 10 Knee Joint Endoprosthesis Set 12 Knee joint endoprosthesis system 14 Knee joint endoprosthesis 16 femoral components 18 Tibial Component 20 Meniscal Components 22 Meniscal Components 24 Prosthesis longitudinal direction 26 First Mirror 28 Tibia 30 shank 32 Femur 34 Coupling Devices 36 Coupling device mirror surface 38 1st joint part 40 Second joint part 42 bottom 44 Protrusion 46 Recess 48 base surface 50 Left femoral component 52 Right femoral component 54 Condyle 56 Medial condyle 58 Lateral condyle 60 Exterior 62 notches 64 Mirrored Femoral Component 66 Meniscus component bearing surface 68 Meniscal component bearing surface 70 Inner sliding surface area 72 Inner sliding surface area 74 Outer sliding surface area 76 Outer sliding surface area 78 Inner sliding pair 80 Inner sliding pair 82 Outer sliding pair 84 Outer sliding pair 86 Inner joint area 88 outer joint area 90 Patient Knee Endoprosthesis Set 92 Second Mirror

Claims

1. A knee joint endoprosthesis set (10) for replacing one of the left and right knee joints of a patient, comprising: a knee joint endoprosthesis (14) for replacing said one knee joint, said endoprosthesis having a femoral component (16), a tibial component (18), and a meniscal component (20); a further meniscal component (22) for replacing said one knee joint; two meniscal components (20, 22) including the meniscal component and the further meniscal component are configured differently; To form the knee joint endoprosthesis (14), one of the two meniscal components (20, 22) is positioned between and cooperates with the femoral component (16) and the tibial component (18); The two meniscal components (20, 22) are configured as mirror images of each other with respect to a first mirror plane (26) extending in a longitudinal direction (24) of the knee joint endoprosthesis; The knee joint endoprosthesis set (10) comprises a coupling device (34) for coupling the tibial component (18) and each of the two meniscal components (20, 22) at a coupling position; the coupling device (34) is configured as a mirror image of a coupling device mirror surface (36) extending in the longitudinal direction (24) of the knee joint endoprosthesis; The femoral component (16) includes a condyle (54) having a medial condyle (56) and a lateral condyle (58); each of the two meniscal components (20, 22) comprising a meniscal component bearing surface (60, 68) cooperating with the medial and lateral condyles in a medial bearing surface region (70, 72) and a lateral bearing surface region (74, 76); the medial condyle (56) and the medial sliding surface region (70, 72) form a medial sliding pair (78, 80), and the lateral condyle (58) and the lateral sliding surface region (74, 76) form a lateral sliding pair (82, 84); the inner sliding surface regions (70, 72) and the outer sliding surface regions (74, 76) have different shapes and / or sizes; A knee joint endoprosthesis set, wherein the condyles (54) of the femoral component (16) are configured in a mirror symmetrical configuration with respect to a femoral component mirror surface (64) extending in the longitudinal direction (24) of the knee joint endoprosthesis.

2. The knee joint endoprosthesis set includes: (a) comprising only one said femoral component (16) and only one said tibial component (18); and / or 2. The knee joint endoprosthesis set according to claim 1, comprising only two meniscal components: the meniscal component (20) and the further meniscal component (22).

3. 3. The knee joint endoprosthesis set according to claim 1, wherein the tibial component (18) and one of the two meniscal components (20, 22) are joined together such that one of the two meniscal components (20, 22) is held immovably on the tibial component (18) at the joining position to form the knee joint endoprosthesis (14).

4. The coupling device (34) comprises two first coupling portions (38) and a second coupling portion (40); one of the two first connecting portions (38) is disposed or formed on each of the two meniscal components (20, 22); the second coupling portion (40) is disposed on or formed on the tibial component (18); 4. The knee joint endoprosthesis set according to claim 1, wherein the first and second connecting portions of one of the two meniscal components are engaged with each other in a force-locking and / or positive-locking manner in the connected position and are not engaged with each other in the separated position.

5. 5. The knee joint endoprosthesis set according to claim 4, wherein the first connecting portion (38) and / or the second connecting portion (40) are mirror images of the connecting device mirror surface (36).

6. The knee joint endoprosthesis set according to any one of claims 1 to 5, wherein the coupling device mirror surface (36) defines the femoral component mirror surface (64).

7. (a) the medial condyle (56) and the medial bearing surface region (70) define a medial joint region (86), and the lateral condyle (58) and the lateral bearing surface region (74) define a lateral joint region (88); One of the medial joint region and the lateral joint region (86, 88) has a higher degree of conformity of the bearing surface shape between the medial or lateral condyle (56, 58) and the associated one of the medial and lateral bearing surface regions (70, 74) than the other. or (b) the medial condyle (56) and the medial bearing surface area (70) define a medial joint area (86), and the lateral condyle (58) and the lateral bearing surface area (74) define a lateral joint area (88); 7. The knee joint endoprosthesis set of claim 1, wherein one of the medial and lateral joint regions has a closer conformity of the bearing surface shape between the medial or lateral condyle and the associated one of the medial and lateral bearing surface regions than the other, and the joint region with the closer conformity of the bearing surface shape defines a ball-and-socket or substantially ball-and-socket joint region.

8. The two meniscal components (20, 22) of the knee joint endoprosthesis (14) are a first connection portion (38) for connection to the tibial component (18); The first coupling portion (38) is configured as a mirror image of the coupling portion mirror surface (36), 8. The knee joint endoprosthesis set according to claim 1, wherein the medial and lateral sliding surface regions (70, 72, 74, 76) are asymmetrically configured with respect to the connecting portion mirror surface (36).

9. 9. The knee joint endoprosthesis set according to claim 8, wherein the shapes and / or sizes of the medial and lateral bearing surface regions (70, 72, 74, 76) are different from each other.

10. A patient knee joint endoprosthesis set (90) for replacing any one of a patient's two knee joints, comprising: A knee joint endoprosthesis set (10) according to any one of claims 1 to 9, a further femoral component (16), A knee joint endoprosthesis set for a patient, wherein one of the two femoral components (16) including the femoral component and the further femoral component is configured in the form of a left femoral component (50), and the other of the two femoral components (16) is configured in the form of a right femoral component (52).

11. 11. The knee joint endoprosthesis set for a patient according to claim 10, wherein the two femoral components (16) and the two meniscal components (20, 22) are configured to be combinable with each other.

12. (a) the two femoral components (16) are configured as mirror images of each other with respect to a second mirror plane (92) extending in the longitudinal direction (24) of the knee joint endoprosthesis; or (b) a set of knee joint endoprostheses for a patient according to claim 10 or 11, wherein the two femoral components (16) are configured as mirror images of each other with respect to a second mirror surface (92) extending in the longitudinal direction (24) of the knee joint endoprosthesis, and the first mirror surface (26) defines the second mirror surface (92).

13. (a) the patient knee endoprosthesis set (90) comprises a further tibial component (18); or (b) the patient's knee joint endoprosthesis set (90) includes an additional tibial component (18), and the tibial component (18) included in the knee joint endoprosthesis set (10) and the additional tibial component (18) are identical in configuration; 13. A knee joint endoprosthesis set for a patient according to any one of claims 10 to 12.

14. A knee joint endoprosthesis system (12), comprising: At least one knee joint endoprosthesis set (10) according to any one of claims 1 to 9, or A knee joint endoprosthesis system comprising a patient knee joint endoprosthesis set (90) according to any one of claims 10 to 13.

15. The knee joint endoprosthesis system (12) comprises at least two knee joint endoprosthesis sets (10), 15. The knee joint endoprosthesis system according to claim 14, wherein in at least two of the knee joint endoprosthesis sets (10), the shape and / or size of the femoral component (16), and / or the two meniscal components (20, 22), and / or the tibial component (18) are different.

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