CN119837681B - Knee pads and knee prostheses - Google Patents

Abstract

The present invention relates to a knee liner and a knee prosthesis. The knee liner comprises a medial fossa and a lateral fossa, at least one of which has a plurality of ellipsoidal concave surfaces. In a projection plane perpendicular to the thickness direction of the knee liner, the outer contour of the concave surfaces is an ellipse, with the major axis of the ellipse extending in the anterior-posterior direction of the knee liner and the minor axis of the ellipse extending in the lateral direction. The ellipse centers of the plurality of concave surfaces are spaced apart in the anterior-posterior direction of the knee liner. The knee liner of the present invention can reduce the probability of joint motion restriction, improve the stability of the knee prosthesis during movement, and provide high patient satisfaction.

Description

Knee joint spacer and knee joint prosthesis

Technical Field

The invention relates to the technical field of medical equipment, in particular to a knee joint pad and a knee joint prosthesis.

Background

The knee joint replacement adopts an artificial knee joint prosthesis to replace diseased joint cartilage and meniscus and retain normal joint ligaments and other tissues, so that the knee joint replacement has the advantages of small wound, quick recovery, reduced pain, more natural movement range and the like, and therefore, the knee joint replacement is widely applied to knee joint treatment.

In the related art, the structural design of the knee joint pad of the knee joint prosthesis is unreasonable, when a patient implanted with the knee joint prosthesis does actions such as buckling, internal rotation, external rotation and the like, the problem of joint limitation exists, the stability of the knee joint prosthesis is poor, and the satisfaction degree of the patient is reduced.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems in the related art to some extent.

Therefore, the embodiment of the invention provides the knee joint pad which has reasonable structural design, can reduce the probability of limited joint movement, is beneficial to improving the stability of the knee joint prosthesis during movement and has higher satisfaction degree of patients.

Embodiments of the present invention provide a knee prosthesis.

The knee joint pad of the embodiment of the invention comprises a medial fossa and a lateral fossa, wherein at least one of the medial fossa and the lateral fossa is internally provided with a plurality of elliptic concave surfaces, the peripheral outline of the concave surfaces is elliptic in a projection plane orthogonal to the thickness direction of the knee joint pad, the major axis of the elliptic shape extends along the front-back direction of the knee joint pad, the minor axis of the elliptic shape extends along the left-right direction of the knee joint pad, and the elliptic circle centers of the plurality of the concave surfaces are arranged at intervals along the front-back direction of the knee joint pad.

According to the knee joint pad provided by the embodiment of the invention, as the peripheral outline of the concave surface is elliptical, and the elliptical centers of the concave surfaces are arranged at intervals along the front-rear direction of the knee joint pad, when the knee joint is at different buckling angles, the femoral prosthesis can be contacted with the concave surfaces at different positions so as to simulate the movement of a natural knee joint, on one hand, the contact area of the knee joint pad and the femoral prosthesis is increased, on the other hand, the limited probability of joint movement can be reduced, the stability of the knee joint prosthesis in movement is improved, and the satisfaction degree of patients is higher.

In some embodiments, the dimensions of the minor axes of the ellipses of the peripheral profiles of the plurality of concavities are the same in the medial fossa, and/or the dimensions of the minor axes of the ellipses of the peripheral profiles of the plurality of concavities are the same in the lateral fossa.

In some embodiments, the concave surface in the medial concavity has a greater peripheral contour than the concave surface in the lateral concavity.

In some embodiments, the number of concavities is at least three in the medial concavity, the centers of the ellipses of the three concavities being spaced apart in the anterior-posterior direction of the knee pad, and/or the number of concavities is at least two in the lateral concavity, the two concavities being spaced apart in the anterior-posterior direction of the knee pad.

In some embodiments, in the medial fossa, the concavity comprises a first medial concavity, a second medial concavity, a third medial concavity, a fourth medial concavity, and a fifth medial concavity, an intersection of a median coronal plane of the knee joint spacer and a sagittal plane passing through a lowest point of the medial fossa forms an ellipse center of the first medial concavity, an ellipse center of the second medial concavity and an ellipse center of the third medial concavity are disposed anterior to an ellipse center of the first medial concavity, an ellipse center of the fourth medial concavity and an ellipse center of the fifth medial concavity are disposed posterior to an ellipse center of the first medial concavity, and/or, in the lateral fossa, the concavity comprises a first lateral concavity, a second lateral concavity, and a third lateral concavity, an intersection of a median coronal plane of the knee joint spacer and a sagittal plane passing through a lowest point of the lateral fossa forms an ellipse center of the first lateral concavity, an ellipse center of the second lateral concavity and an ellipse center of the third lateral concavity are disposed anterior to a circle center of the first lateral concavity, respectively.

In some embodiments, the peripheral contour of the concavity has a dimension A1 in the left-to-right direction of the knee pad, wherein 20 mm≤A1≤40 mm, and/or the peripheral contour of the concavity has a dimension B1 in the anterior-posterior direction of the knee pad, wherein 38 mm≤B1≤52 mm, in the medial concavity, and/or the peripheral contour of the concavity has a dimension A2 in the left-to-right direction of the knee pad, wherein 18 mm≤A2≤38 mm, and/or the peripheral contour of the concavity has a dimension B2 in the anterior-posterior direction of the knee pad, wherein 35 mm≤B2≤50 mm.

In some embodiments, the knee pad has a median sagittal plane at a distance L1 from a sagittal plane passing through the lowest point of the medial fossa, wherein 20 mm≤L1≤30 mm, and/or the knee pad has a median sagittal plane at a distance L2 from a sagittal plane passing through the lowest point of the lateral fossa, wherein 20 mm≤L2≤30 mm.

In some embodiments, the center of the ellipse of each adjacent two of the concavities is equidistant along the anterior-posterior direction of the knee pad in the medial concavity and/or the center of the ellipse of each adjacent two of the concavities is equidistant along the anterior-posterior direction of the knee pad in the lateral concavity.

In some embodiments, in the medial fossa, the distance between the centers of ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee pad is C1, wherein 1 mm≤C1≤2mm, and/or in the lateral fossa, the distance between the centers of ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee pad is C2, wherein 2 mm≤C2≤4mm.

A knee joint prosthesis according to another embodiment of the present invention includes a femoral prosthesis including a medial condyle and a lateral condyle, and a knee pad, the knee pad being in accordance with any one of the embodiments of the present invention, the medial condyle cooperating with the medial fossa, the lateral condyle cooperating with the lateral fossa.

According to the knee joint prosthesis provided by the embodiment of the invention, as the peripheral outline of the concave surface is elliptical, and the elliptical centers of the concave surfaces are arranged at intervals along the front-rear direction of the knee joint pad, when the knee joint is at different buckling angles, the femoral prosthesis can be contacted with the concave surfaces at different positions so as to simulate the movement of a natural knee joint, on one hand, the contact area of the knee joint pad and the femoral prosthesis is increased, on the other hand, the limited probability of joint movement can be reduced, the stability of the knee joint prosthesis in movement is improved, and the satisfaction degree of a patient is higher.

Drawings

Fig. 1 is a top view of a knee joint spacer in accordance with an embodiment of the present invention.

Figure 2 is a cross-sectional view of the medial fossa position of a knee joint spacer of an embodiment of the present invention.

Fig. 3 is a simplified diagram of a top view of a medial fossa of a knee joint spacer of an embodiment of the present invention.

Figure 4 is a cross-sectional view of the lateral socket position of a knee joint spacer in accordance with an embodiment of the present invention.

Figure 5 is a simplified diagram of a top view of a lateral socket of a knee joint spacer of an embodiment of the present invention.

Fig. 6 is a schematic structural view of a knee joint spacer in accordance with an embodiment of the present invention.

Reference numerals:

100. Knee joint pads;

110. medial fossa, 120, lateral fossa;

101. concave surface 1011, first inner concave surface, 1012, second inner concave surface, 1013, third inner concave surface, 1014, fourth inner concave surface, 1015, fifth inner concave surface, 1016, first outer concave surface, 1017, second outer concave surface, 1018, third outer concave surface.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.

In order to better explain and illustrate the technical scheme of the invention, the direction and the like related to the invention are explained and illustrated in combination with the conventional description method in the field.

In the field of anatomies and medical devices, the directions and planes of the medial, lateral, anterior, posterior, distal, proximal, sagittal, coronal, cross-sectional, etc. have specific meanings and are well known to those skilled in the art, and unless otherwise indicated, these terms refer to the meanings recognized by those skilled in the art.

Generally, when describing a human body, joint or prosthesis, three types of cuts are typically referred to, sagittal, coronal and transverse. The sagittal plane refers to a longitudinal section dividing a human body or a joint into a left part and a right part from the front-back direction, wherein the sagittal plane passing through the center of the human body is the median sagittal plane, and the sagittal plane divides the human body into two parts which are equal from left to right. The coronal plane refers to a longitudinal plane that divides the body or joint into anterior and posterior parts from the left-right direction, and is perpendicular to the sagittal plane. The cross section is a plane parallel to the ground plane and dividing the human body or joint into an upper part and a lower part, and the cross section is mutually perpendicular to the coronal plane and the sagittal plane.

It will be appreciated that when describing a knee joint or knee prosthesis, sagittal, coronal and transverse planes refer to the tangential plane of a person when standing normally, with the knee angle of the knee joint being 0 °. When the knee joint or the knee joint prosthesis stretches and bends, or the human body posture is adjusted, the section can be changed.

Generally, when describing a human body, joint or prosthesis, three different directions are referred to, distal to proximal, medial to lateral and anterior to posterior. Wherein, the far end refers to the end of the human body or the joint relatively far away from the trunk. Proximal refers to the side of the body or joint that is relatively close to the medial aspect of the torso that is relatively close to the median sagittal plane of the body. Lateral refers to the side relatively far from the median sagittal plane of the human body. Anterior refers to the end of the sagittal plane that is relatively close to the abdomen. The posterior refers to the end of the sagittal plane that is relatively close to the back.

The knee joint spacer and the knee joint prosthesis according to the embodiments of the present invention are described below with reference to fig. 1 to 6.

As shown in fig. 1 to 5, the knee joint spacer 100 of the embodiment of the present invention includes a medial fossa 110 and a lateral fossa 120, at least one of the medial fossa 110 and the lateral fossa 120 has a plurality of concave surfaces 101 having an ellipsoidal shape therein, and in a projection plane orthogonal to a thickness direction of the knee joint spacer 100, an outer circumferential contour of the concave surfaces 101 is an ellipse, a major axis of the ellipse extends in an anterior-posterior direction of the knee joint spacer 100, a minor axis of the ellipse extends in a lateral direction of the knee joint spacer 100, and elliptical centers of the plurality of concave surfaces 101 are arranged at intervals in the anterior-posterior direction of the knee joint spacer 100.

It will be appreciated that the compartment defined by medial fossa 110 and/or lateral fossa 120 is a generally ellipsoidal cavity, and that the peripheral profile of concave surface 101 of medial fossa 110 and/or concave surface 101 of lateral fossa 120 is elliptical in a plane of projection orthogonal to the thickness direction of knee joint spacer 100.

For example, as shown in fig. 1 and 3, the medial fossa 110 has a plurality of concaves 101 having ellipses therein, and the centers of the ellipses of the plurality of concaves 101 are spaced apart in the anterior-posterior direction of the knee joint spacer 100.

As another example, as shown in fig. 1 and 5, the lateral fossa 120 has a plurality of concaves 101 having ellipses therein, and the centers of the ellipses of the plurality of concaves 101 are spaced apart in the anterior-posterior direction of the knee joint spacer 100.

According to the knee joint spacer 100 of the embodiment of the present invention, since the outer circumferential profile of the concave surface 101 is elliptical, and the elliptical centers of the plurality of concave surfaces 101 are spaced apart in the anterior-posterior direction of the knee joint spacer 100, when the knee joint is at different flexion angles, the femoral prosthesis can contact with the concave surface 101 at different positions to simulate the movement of the natural knee joint, on the one hand, the contact area between the knee joint spacer 100 and the femoral prosthesis is increased, on the other hand, the probability of limited movement of the joint can be reduced, which is beneficial to improving the stability of the knee joint prosthesis during movement, and the satisfaction of patients is high.

As shown in fig. 2 and 3, the medial fossa 110 is taken as an example. The elliptical contour centers of the plurality of concavities 101 in the medial fossa 110 are spaced apart in the anterior-posterior direction of the knee pad 100, the major axis of the elliptical contour extends in the anterior-posterior direction of the knee pad 100, and the minor axis of the elliptical contour extends in the lateral direction of the knee pad 100, such that the contact area of the medial condyle of the femoral prosthesis with the medial fossa 110 of the knee pad 100 is large. When the femoral prosthesis flexes with knee joint movement, the medial condyle may be displaced in the anterior-posterior direction to mate with the concave surface 101 at a different location of the medial fossa 110, thereby mimicking the movement characteristics of a natural knee joint such that the patient forgets the joint replacement.

The knee joint spacer 100 of the embodiment of the present invention adopts the above-described structural design of the medial fossa 110, which can implement an inner shaft-like concept, the structure is consistent with human knee joint kinematics, and the inner shaft-like movement design mimics the movement characteristics of a natural knee joint, particularly the movement pattern with the medial fossa 110 as the axis during flexion. This design not only improves the stability of the knee joint, but also enhances patient satisfaction.

Alternatively, as shown in FIG. 1, the peripheral profile of the concave surface 101 in the medial fossa 110 is greater than the peripheral profile of the concave surface 101 in the lateral fossa 120. It will be appreciated that the concave surface 101 of the medial condyle 110 has a greater contact area with the medial condyle than the concave surface 101 of the lateral condyle 120, thereby providing a greater amount of displacement to the articular surface of the medial condyle and a different concave surface 101 of the medial condyle may contact the articular surface of the medial condyle when the anterior-posterior displacement occurs to avoid stress concentrations. The knee pad 100 of embodiments of the present invention may provide a high contact area, simulate natural knee motion, retain more bone mass, and reduce the incidence of joint instability, significantly improving the effectiveness of knee arthroplasty and patient satisfaction.

According to the human meniscus anatomy medial being greater than lateral anatomical features, the pocket contact surface in medial fossa 110 of the present invention is greater than the pocket contact surface in lateral fossa 120, thereby providing a greater amount of displacement of the articular surface of the medial condyle, which is properly displaced to contact the concave surface 101 at a different location of medial fossa 110.

Alternatively, as shown in fig. 2 and 3, in the medial fossa 110, the minor axes of the ellipses of the outer circumferential profile of the plurality of concavities 101 are the same size. Thus, when the articular surface of the medial condyle is displaced anteroposterior and contacts the different concave surface 101 of the medial fossa 110, the stability of the contact of the medial condyle with the medial fossa 110 can be ensured, so that the patient can forget joint replacement, and the satisfaction of the patient is improved.

As shown in fig. 4 and 5, in the outside socket 120, the dimensions of the minor axes of the ellipses of the outer circumferential profile of the plurality of concave surfaces 101 are the same. Thus, when the articular surface of the lateral condyle is displaced anteriorly and posteriorly and contacts the different concave surface 101 of the lateral fossa 120, the stability of the contact of the lateral condyle with the lateral fossa 120 can be ensured, so that the patient can forget the joint replacement, and the satisfaction of the patient is improved.

In some embodiments, as shown in fig. 2 and 3, in medial fossa 110, there are at least three concavities 101, with the centers of the ellipses of the three concavities 101 spaced in the anterior-posterior direction of knee joint spacer 100. For example, in medial fossa 110, concavity 101 may be three, four, five, or six.

Preferably, in medial concavity 110, there are at least six concavities 101.

Specifically, as shown in fig. 2 and 3, in medial fossa 110, concave surface 101 includes a first medial concave surface 1011, a second medial concave surface 1012, a third medial concave surface 1013, a fourth medial concave surface 1014, and a fifth medial concave surface 1015, an intersection of a median coronal plane of knee joint spacer 100 and a sagittal plane passing through a lowest point of medial fossa 110 constitutes an ellipse center O1 of first medial concave surface 1011, an ellipse center O2 of second medial concave surface 1012 and an ellipse center O3 of third medial concave surface 1013 are disposed on a front side of an ellipse center of first medial concave surface 1011O1, and an ellipse center O4 of fourth medial concave surface 1014 and an ellipse center O5 of fifth medial concave surface 1015 are disposed on a rear side of an ellipse center O1 of first medial concave surface 1011.

In other words, the center O3 of the ellipse of the third inside concave surface 1013, the center O2 of the ellipse of the second inside concave surface 1012, the center O1 of the ellipse of the first inside concave surface 1011, the center O4 of the ellipse of the fourth inside concave surface 1014, and the center O5 of the ellipse of the fifth inside concave surface 1015 are arranged in this order in the front-to-rear direction.

Through experimental study, the inventor of the present application found that when the above number and arrangement of the concave surfaces 101 in the medial fossa 110 are adopted, the stability of the contact between the medial condyle and the medial fossa 110 can be ensured, and the movement principle of the medial condyle is closer to that of the natural knee joint, which is beneficial to enhancing the satisfaction of patients.

Alternatively, as shown in fig. 4 and 5, in the lateral socket 120, at least two concave surfaces 101 are provided, and the two concave surfaces 101 are spaced apart in the anterior-posterior direction of the knee joint spacer 100. For example, in the lateral fossa 120, the concavity 101 may be two, three, four, five, or six.

Specifically, as shown in fig. 4 and 5, in the lateral fossa 120, the concave surface 101 includes a first lateral concave surface 1016, a second lateral concave surface 1017, and a third lateral concave surface 1018, an intersection of the median coronal plane of the knee joint spacer 100 and a sagittal plane passing through the lowest point of the lateral fossa 120 constitutes an ellipse center P1 of the first lateral concave surface 1016, and an ellipse center P2 of the second lateral concave surface 1017 and an ellipse center P3 of the third lateral concave surface 1018 are disposed on the anterior-posterior sides of the ellipse center P1 of the first lateral concave surface 1016, respectively.

In other words, the center P2 of the ellipse of the second outside concave surface 1017, the center P1 of the ellipse of the first outside concave surface 1016, and the center P3 of the ellipse of the third outside concave surface 1018 are arranged in order in the front-to-rear direction.

The inventor of the present application found through experimental study that when the above number and arrangement of the concave surfaces 101 in the lateral fossa 120 are adopted, the stability of the contact between the lateral condyle and the lateral fossa 120 can be ensured, and the movement principle of the lateral condyle is closer to the natural knee joint, which is beneficial to enhancing the satisfaction of patients.

It will be appreciated that the knee liner 100, with the above-described structural arrangement, ensures that the contact area of the femoral condyle with the liner in the sagittal and coronal planes is maximized. Specifically, the contact area of the medial condyle with the medial fossa 110 may be 97% or more and the contact area of the lateral condyle with the lateral fossa 120 may be 89% or more. The design mode can reduce the abrasion of the polyethylene prosthesis and avoid point contact or stress concentration, thereby remarkably prolonging the service life of the prosthesis, reducing the occurrence rate of instability of joints and being beneficial to improving the stability of the knee joint prosthesis during movement.

Alternatively, as shown in FIG. 3, in the medial fossa 110, the outer circumferential contour of the concave surface 101 has a dimension A1 in the left-right direction of the knee joint spacer 100, wherein 20 mm≤A1≤40 mm. For example, A1 may be 20mm, 25mm, 30mm, 35mm, 40mm.

In the medial fossa 110, the outer peripheral contour of the concave surface 101 has a dimension B1 in the anterior-posterior direction of the knee joint spacer 100, wherein 38 mm+.b1+.52mm. For example, B1 may be 38mm, 42mm, 45mm, 48mm, 50mm, 52mm.

Through experimental study, the inventor of the present application finds that when the contour of the concave surface 101 in the medial fossa 110 adopts the above parameter range, the contact area with the medial fossa 110 is larger during the medial condyle movement, and the stability during the movement is higher, which is closer to the movement principle of the natural knee joint, thereby being beneficial to enhancing the satisfaction degree of patients.

Alternatively, as shown in FIG. 5, in the lateral fossa 120, the outer circumferential contour of the concave surface 101 has a dimension A2 in the left-right direction of the knee joint spacer 100, wherein 18 mm≤A2≤38 mm. For example, A2 may be 18mm, 20mm, 25mm, 30mm, 35mm, 38mm.

In the lateral fossa 120, the outer peripheral contour of the concave surface 101 has a dimension B2 in the anterior-posterior direction of the knee joint spacer 100, wherein 35 mm≤b2≤50 mm. For example, B2 may be 35mm, 38mm, 42mm, 45mm, 48mm, 50mm.

Through experimental study, the inventor of the present application finds that when the profile of the concave surface 101 in the lateral fossa 120 adopts the above parameter range, the contact between the lateral fossa 120 and the lateral condyle 120 can be ensured to be more stable when the lateral condyle moves, the matching degree between the lateral condyle and the lateral fossa 120 is better, and the lateral condyle is closer to the movement principle of the natural knee joint, thereby being beneficial to enhancing the satisfaction degree of patients.

Alternatively, as shown in FIG. 1, the distance between the mid-sagittal plane of the knee joint spacer 100 and the sagittal plane passing through the lowest point of the medial fossa 110 is L1, wherein 20 mm≤L1≤30 mm. For example, L1 may be 20mm, 22mm, 24mm, 26mm, 28mm, 30mm.

As shown in FIG. 1, the distance between the mid-sagittal plane of the knee joint spacer 100 and the sagittal plane passing through the lowest point of the lateral fossa 120 is L2, where 20mm < L2 < 30mm. For example, L2 may be 20mm, 22mm, 24mm, 26mm, 28mm, 30mm.

The inventor of the present application has found through experimental study that when the medial fossa 110 and the lateral fossa 120 of the knee joint spacer 100 are disposed in the above manner, wear of the knee joint spacer 100 and the femoral prosthesis can be slowed down, and the probability of limited joint movement is reduced, which is advantageous for improving stability of the knee joint prosthesis during movement, and patient satisfaction is high.

Alternatively, as shown in fig. 3, in the medial fossa 110, the centers of ellipses of each adjacent two of the concavities 101 are equally spaced in the anterior-posterior direction of the knee joint spacer 100. For example, the distance between the center O3 of the ellipse of the third inside concave surface 1013 and the center O2 of the ellipse of the second inside concave surface 1012 is equal to the center O1 of the ellipse of the first inside concave surface 1011 and the center O2 of the ellipse of the second inside concave surface 1012. The distance between the center O5 of the ellipse of the fifth inner concave surface 1015 and the center O4 of the ellipse of the fourth inner concave surface 1014 and the center O1 of the ellipse of the first inner concave surface 1011 are equal to the center O4 of the ellipse of the fourth inner concave surface 1014. Therefore, the medial condyle can be contacted with the medial fossa 110 more stably during movement, the matching degree of the medial condyle and the medial fossa 110 is better, and the medial condyle is closer to the movement principle of a natural knee joint, thereby being beneficial to enhancing the satisfaction degree of patients.

Alternatively, as shown in fig. 5, in the lateral fossa 120, the centers of ellipses of each adjacent two of the concavities 101 are equally spaced in the anterior-posterior direction of the knee joint spacer 100. In other words, the distance between the center P2 of the ellipse of the second outside concave surface 1017 and the center P1 of the ellipse of the first outside concave surface 1016 is equal to the distance between the center P3 of the ellipse of the third outside concave surface 1018 and the center P1 of the ellipse of the first outside concave surface 1016. Therefore, the contact between the lateral condyle and the lateral fossa 120 is more stable when the lateral condyle moves, the matching degree of the lateral condyle and the lateral fossa 120 is better, and the lateral condyle is closer to the movement principle of a natural knee joint, thereby being beneficial to enhancing the satisfaction degree of patients.

Alternatively, as shown in FIG. 3, in the medial fossa 110, the centers of ellipses of two adjacent concavities 101 are spaced apart by C1 in the anterior-posterior direction of the knee joint spacer 100, wherein 1 mm≤C1≤2mm. For example, C1 may be 1mm, 1.5mm, 2mm.

As shown in FIG. 4, in the lateral fossa 120, the centers of ellipses of the adjacent two concavities 101 are spaced apart from each other by C2 in the anteroposterior direction of the knee joint spacer 100, wherein 2 mm≤C2≤4 mm. For example, C2 may be 2mm, 2.5mm, 3mm, 4mm.

Buckling during normal activities of the human body is accompanied by proper internal and external rotation. When the knee is initially pronated, the articular surface of the lateral condyle initially contacts the first lateral concavity 1016 and the articular surface of the posterior lateral condyle moves anteriorly, gradually contacting the second lateral concavity 1017, whereupon the articular surface of the lateral condyle moves approximately slowly anteriorly by 2-4mm. Meanwhile, when the knee joint is preliminarily pronated, the articular surface of the medial condyle initially contacts the first medial concavity 1011 and the articular surface of the posterior medial condyle moves posteriorly, and the articular surface of the medial condyle gradually contacts the fourth medial concavity 1014, at which time the articular surface of the medial condyle moves about 1mm slowly posteriorly.

The movement mode of the femoral prosthesis can easily cause the patient to forget joint replacement so as to realize the inner shaft-like concept, the structure is consistent with the human knee joint kinematics, the inner shaft type movement design simulates the movement characteristics of a natural knee joint, the stability of the knee joint is improved, and the satisfaction degree of the patient is enhanced.

A knee joint prosthesis according to another embodiment of the present invention includes a femoral prosthesis including a medial condyle and a lateral condyle, and a knee joint liner 100, the knee joint liner 100 of the present invention, the medial condyle cooperating with a medial fossa 110 and the lateral condyle cooperating with a lateral fossa 120.

According to the knee joint prosthesis of the embodiment of the invention, as the peripheral outline of the concave surface 101 is elliptical, and the elliptical centers of the plurality of concave surfaces 101 are arranged at intervals along the front-rear direction of the knee joint pad 100, when the knee joint is at different buckling angles, the femoral prosthesis can be contacted with the concave surfaces 101 at different positions so as to simulate the movement of a natural knee joint, on one hand, the contact area between the knee joint pad 100 and the femoral prosthesis is increased, on the other hand, the limited probability of joint movement can be reduced, the stability of the knee joint prosthesis during movement is improved, and the satisfaction degree of patients is higher.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed, mechanically connected, electrically connected, or communicable with each other, directly connected, indirectly connected through an intervening medium, or in communication between two elements or in an interactive relationship between two elements, unless otherwise explicitly specified. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

For purposes of this disclosure, the terms "one embodiment," "some embodiments," "example," "a particular example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While the above embodiments have been shown and described, it should be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives, and variations of the above embodiments may be made by those of ordinary skill in the art without departing from the scope of the invention.

Claims (9)

1. A knee joint spacer characterized by comprising a medial fossa and a lateral fossa, at least one of the medial fossa and the lateral fossa having a plurality of concaves of ellipses therein, the outer circumferential contour of the concaves being an ellipse in a projection plane orthogonal to the thickness direction of the knee joint spacer, the major axis of the ellipse extending in the anterior-posterior direction of the knee joint spacer, the minor axis of the ellipse extending in the lateral direction of the knee joint spacer, the centers of the ellipses of the plurality of concaves being spaced apart in the anterior-posterior direction of the knee joint spacer;

In the medial fossa, the concave surfaces comprise a first medial concave surface, a second medial concave surface, a third medial concave surface, a fourth medial concave surface and a fifth medial concave surface, an intersection point of a median coronal plane of the knee joint spacer and a sagittal plane passing through a lowest point of the medial fossa forms an ellipse center of the first medial concave surface, the ellipse center of the second medial concave surface and the ellipse center of the third medial concave surface are arranged at a front side of the ellipse center of the first medial concave surface, and the ellipse center of the fourth medial concave surface and the ellipse center of the fifth medial concave surface are arranged at a rear side of the ellipse center of the first medial concave surface;

And/or, in the lateral fossa, the concave surface comprises a first lateral concave surface, a second lateral concave surface and a third lateral concave surface, an intersection point of a median coronal plane of the knee joint pad and a sagittal plane passing through a lowest point of the lateral fossa forms an ellipse circle center of the first lateral concave surface, and the ellipse circle center of the second lateral concave surface and the ellipse circle center of the third lateral concave surface are respectively arranged on front and rear sides of the ellipse circle center of the first lateral concave surface.

2. The knee joint spacer of claim 1 wherein the dimensions of the minor axes of the ellipses of the peripheral contours of the plurality of concavities are the same in the medial fossa;

And/or, in the lateral fossa, the dimensions of minor axes of ellipses of the peripheral profiles of the plurality of concavities are the same.

3. The knee joint spacer of claim 1, wherein a peripheral contour of the concavity in the medial concavity is greater than a peripheral contour of the concavity in the lateral concavity.

4. The knee joint spacer of claim 1 wherein in said medial fossa, said concavities are at least three, the elliptical centers of the three concavities being spaced apart in the anterior-posterior direction of said knee joint spacer;

And/or, in the lateral fossa, at least two of the concavities are spaced apart in the anterior-posterior direction of the knee joint spacer.

5. The knee joint spacer of claim 1, wherein in the medial fossa, a dimension of a peripheral contour of the concave surface along a left-right direction of the knee joint spacer is A1, wherein 20mm ∈a1 ∈40mm;

And/or, in the medial fossa, a dimension of the peripheral contour of the concave surface in the anterior-posterior direction of the knee joint spacer is B1, wherein 38mm ∈b1 ∈52mm;

And/or, in the lateral fossa, the peripheral contour of the concave surface has a dimension A2 in the left-right direction of the knee joint pad, wherein 18mm < A2 < 38mm;

And/or, in the lateral fossa, a dimension of the peripheral contour of the concave surface in the anterior-posterior direction of the knee joint pad is B2, wherein 35mm ∈b2 ∈50mm.

6. The knee joint spacer of claim 1, wherein a median sagittal plane of the knee joint spacer is spaced apart from a sagittal plane passing through a lowest point of the medial fossa by L1, wherein 20mm ∈l1 ∈30mm;

And/or the distance between the median sagittal plane of the knee joint spacer and the sagittal plane passing through the lowest point of the lateral fossa is L2, wherein L2 is 20mm < 30mm.

7. The knee bolster of claim 1 wherein in said medial fossa, the center of the ellipses of each adjacent two of said concavities are equally spaced in the anterior-posterior direction of said knee bolster;

And/or, in the lateral fossa, the distances between the centers of ellipses of every two adjacent concave surfaces along the front-back direction of the knee joint pad are equal.

8. The knee joint spacer of claim 1, wherein in said medial fossa, the spacing between the centers of ellipses of two adjacent said concavities along the anterior-posterior direction of said knee joint spacer is C1, wherein 1mm ∈c1 ∈2mm;

And/or, in the lateral fossa, the distance between the centers of ellipses of two adjacent concave surfaces along the front-back direction of the knee joint pad is C2, wherein C2 is more than or equal to 2mm and less than or equal to 4mm.

9. A knee joint prosthesis, which comprises a main body, characterized by comprising the following steps:

A femoral prosthesis comprising a medial condyle and a lateral condyle;

A knee pad, the knee pad being as claimed in any one of claims 1 to 8, the medial condyle cooperating with the medial fossa, the lateral condyle cooperating with the lateral fossa.