Knee pads and knee prostheses

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

Technical Field

[0001] The present invention relates to the technical field of medical devices, in particular to a knee joint pad and a knee joint prosthesis. Background Art

[0002] Knee replacement surgery uses an artificial knee prosthesis to replace the diseased articular cartilage and meniscus while retaining normal joint ligaments and other tissues. It has the advantages of less trauma, faster recovery, reduced pain and a more natural range of motion. Therefore, knee replacement surgery is widely used in knee joint treatment.

[0003] In the related art, the structural design of the knee joint pad of the knee joint prosthesis is unreasonable. When patients with implanted knee joint prostheses perform movements such as flexion, internal rotation and external rotation, there is a problem of joint restriction, and the stability of the knee joint prosthesis is poor, which reduces patient satisfaction. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention provides a knee joint liner with a reasonable structural design, which can reduce the probability of joint movement restriction, is conducive to improving the stability of the knee joint prosthesis during movement, and has high patient satisfaction.

[0006] An embodiment of the present invention provides a knee joint prosthesis.

[0007] A knee joint pad according to an embodiment of the present invention includes: a medial fossa and a lateral fossa, at least one of the medial fossa and the lateral fossa having a plurality of ellipsoidal concave surfaces, wherein the outer peripheral contour of the concave surfaces in a projection plane orthogonal to the thickness direction of the knee joint pad is an ellipse, the major axis of the ellipse extending along the anterior-posterior direction of the knee joint pad, and the minor axis of the ellipse extending along the lateral direction of the knee joint pad, and the elliptical centers of the plurality of concave surfaces are arranged at intervals along the anterior-posterior direction of the knee joint pad.

[0008] According to the knee joint pad of the embodiment of the present invention, since the outer peripheral contour of the concave surface is elliptical, and the elliptical centers of the multiple concave surfaces are arranged at intervals along the anterior-posterior direction of the knee joint pad, when the knee joint is in different flexion angles, the femoral prosthesis can contact the concave surfaces at different positions to simulate the movement of the natural knee joint. On the one hand, the contact area between the knee joint pad and the femoral prosthesis is increased, and on the other hand, the probability of restricted joint movement can be reduced, which is conducive to improving the stability of the knee joint prosthesis during movement and has high patient satisfaction.

[0009] In some embodiments, in the medial fossa, the minor axes of the ellipses of the outer peripheral contours of the plurality of concavities are the same, and / or in the lateral fossa, the minor axes of the ellipses of the outer peripheral contours of the plurality of concavities are the same.

[0010] In some embodiments, the outer peripheral contour of the concavity in the medial fossa is larger than the outer peripheral contour of the concavity in the lateral fossa.

[0011] In some embodiments, in the medial fossa, there are at least three concave surfaces, and the elliptical centers of the three concave surfaces are arranged at intervals along the anterior-posterior direction of the knee joint pad; and / or, in the lateral fossa, there are at least two concave surfaces, and the two concave surfaces are arranged at intervals along the anterior-posterior direction of the knee joint pad.

[0012] In some embodiments, in the medial fossa, the concave surface includes 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; the intersection of the median coronal plane of the knee liner and the sagittal plane passing through the lowest point of the medial fossa constitutes the ellipse center of the first medial concave surface; the ellipse centers of the second and third medial concave surfaces are arranged anterior to the ellipse center of the first medial concave surface; and the ellipse centers of the fourth and fifth medial concave surfaces are arranged posterior to the ellipse center of the first medial concave surface; and / or, in the lateral fossa, the concave surface includes a first lateral concave surface, a second lateral concave surface, and a third lateral concave surface; the intersection of the median coronal plane of the knee liner and the sagittal plane passing through the lowest point of the lateral fossa constitutes the ellipse center of the first lateral concave surface; the ellipse centers of the second and third lateral concave surfaces are respectively arranged anterior and posterior to the ellipse center of the first lateral concave surface.

[0013] In some embodiments, in the medial fossa, the dimension of the peripheral contour of the concave surface along the left-right direction of the knee joint pad is A1, wherein 20 mm ≤ A1 ≤ 40 mm; and / or, in the medial fossa, the dimension of the peripheral contour of the concave surface along the front-to-back direction of the knee joint pad is B1, wherein 38 mm ≤ B1 ≤ 52 mm; and / or, in the lateral fossa, the dimension of the peripheral contour of the concave surface along the left-right direction of the knee joint pad is A2, wherein 18 mm ≤ A2 ≤ 38 mm; and / or, in the lateral fossa, the dimension of the peripheral contour of the concave surface along the front-to-back direction of the knee joint pad is B2, wherein 35 mm ≤ B2 ≤ 50 mm.

[0014] In some embodiments, the distance between the median sagittal plane of the knee joint pad and the sagittal plane passing through the lowest point of the medial fossa is L1, wherein 20 mm ≤ L1 ≤ 30 mm; and / or the distance between the median sagittal plane of the knee joint pad and the sagittal plane passing through the lowest point of the lateral fossa is L2, wherein 20 mm ≤ L2 ≤ 30 mm.

[0015] In some embodiments, in the medial fossa, the distances between the centers of the ellipses of each two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad are equal; and / or, in the lateral fossa, the distances between the centers of the ellipses of each two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad are equal.

[0016] In some embodiments, in the medial fossa, the distance between the centers of the ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad is C1, wherein 1mm≤C1≤2mm; and / or, in the lateral fossa, the distance between the centers of the ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad is C2, wherein 2mm≤C2≤4mm.

[0017] A knee joint prosthesis according to another embodiment of the present invention comprises: a femoral prosthesis including a medial condyle and a lateral condyle; and a knee joint liner, wherein the knee joint liner is any one of the knee joint liner described in any one of the embodiments of the present invention, the medial condyle cooperates with the medial fossa, and the lateral condyle cooperates with the lateral fossa.

[0018] According to the knee joint prosthesis of the embodiment of the present invention, since the outer peripheral contour of the concave surface is elliptical, and the elliptical centers of the multiple concave surfaces are arranged at intervals along the anterior-posterior direction of the knee joint pad, when the knee joint is in different flexion angles, the femoral prosthesis can contact the concave surfaces at different positions to simulate the movement of the natural knee joint. On the one hand, the contact area between the knee joint pad and the femoral prosthesis is increased, and on the other hand, the probability of restricted joint movement can be reduced, which is conducive to improving the stability of the knee joint prosthesis during movement and has high patient satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. 4 is a top view of a knee joint pad according to an embodiment of the present invention.

[0020] Figure 2 FIG. 4 is a cross-sectional view of the medial socket of a knee joint pad according to an embodiment of the present invention.

[0021] Figure 3 FIG. 1 is a simplified top view of the medial socket of a knee joint pad according to an embodiment of the present invention.

[0022] Figure 4 FIG. 4 is a cross-sectional view of the lateral socket of a knee joint pad according to an embodiment of the present invention.

[0023] Figure 5 FIG. 1 is a simplified top view of the lateral socket of a knee joint pad according to an embodiment of the present invention.

[0024] Figure 6 Schematic diagram of the structure of a knee joint pad according to an embodiment of the present invention.

[0025] Reference numerals:

[0026] 100. Knee pads;

[0027] 110, medial fossa; 120, lateral fossa;

[0028] 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

[0029] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0030] In order to better explain and illustrate the technical solution of the present invention, the directions and the like involved in the present invention are explained and illustrated in combination with the conventional description methods in the art.

[0031] In the field of anatomy and medical devices, directions and planes such as inside, outside, anterior, posterior, distal, proximal, sagittal, coronal, and cross-sectional planes have specific meanings and are well known to those skilled in the art. Unless otherwise specified, these terms refer to the meanings recognized by those skilled in the art.

[0032] Generally, when describing the human body, joints or prostheses, the following three sections are usually involved: sagittal plane, coronal plane and cross-sectional plane. Among them, the sagittal plane refers to the longitudinal section that divides the human body or joint into left and right parts from the front-to-back direction. Among them, the sagittal plane passing through the center of the human body is the median sagittal plane, which divides the human body into two equal left and right parts. The coronal plane refers to the longitudinal section that divides the human body or joint into front and back parts from the left-to-right direction. The coronal plane is perpendicular to the sagittal plane. The cross-sectional plane is a plane parallel to the ground plane that divides the human body or joint into upper and lower parts. The cross-sectional plane is perpendicular to the coronal and sagittal planes.

[0033] It should be understood that when describing the knee joint or knee prosthesis, the sagittal, coronal, and transverse planes refer to the view taken when the person is standing upright, with the knee flexed at 0°. The view may change as the knee joint or knee prosthesis flexes or extends, or as the person's posture changes.

[0034] Generally, when describing the human body, joints, or prostheses, three different directions are used: proximal and distal, medial and posterior. Distal refers to the end of a body or joint that is relatively farthest from the trunk. Proximal refers to the end of a body or joint that is relatively close to the trunk. Medial refers to the side closer to the midsagittal plane of the body. Lateral refers to the side farther from the midsagittal plane of the body. Anterior refers to the end of the sagittal plane that is closer to the abdomen. Posterior refers to the end of the sagittal plane that is closer to the back.

[0035] Please refer to the following Figures 1 to 6 A knee joint liner and a knee joint prosthesis according to embodiments of the present invention are described.

[0036] like Figures 1 to 5 As shown, the knee joint pad 100 according to 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 ellipsoidal concave surfaces 101. In a projection plane perpendicular to the thickness direction of the knee joint pad 100, the outer peripheral contour of the concave surface 101 is an ellipse. The major axis of the ellipse extends along the anterior-posterior direction of the knee joint pad 100, and the minor axis of the ellipse extends along the lateral direction of the knee joint pad 100. The elliptical centers of the plurality of concave surfaces 101 are arranged at intervals along the anterior-posterior direction of the knee joint pad 100.

[0037] It can be understood that the chamber enclosed by the medial fossa 110 and / or the lateral fossa 120 is generally an ellipsoidal cavity, and in the projection plane perpendicular to the thickness direction of the knee joint liner 100, the outer peripheral contour of the concave surface 101 of the medial fossa 110 and / or the concave surface 101 of the lateral fossa 120 is an ellipse.

[0038] For example, Figure 1 and Figure 3 As shown, the medial fossa 110 has a plurality of ellipsoidal concave surfaces 101 , and the elliptical centers of the plurality of concave surfaces 101 are arranged at intervals along the front-back direction of the knee joint liner 100 .

[0039] For example, Figure 1 and Figure 5 As shown, the lateral socket 120 has a plurality of ellipsoidal concave surfaces 101 , and the elliptical centers of the plurality of concave surfaces 101 are arranged at intervals along the front-back direction of the knee joint liner 100 .

[0040] According to the knee joint pad 100 of the embodiment of the present invention, since the outer peripheral contour of the concave surface 101 is elliptical, and the elliptical centers of the multiple concave surfaces 101 are arranged at intervals along the front-to-back direction of the knee joint pad 100, when the knee joint is in different flexion angles, the femoral prosthesis can contact the concave surfaces 101 at different positions to simulate the movement of the natural knee joint. On the one hand, the contact area between the knee joint pad 100 and the femoral prosthesis is increased, and on the other hand, the probability of joint movement being restricted can be reduced, which is conducive to improving the stability of the knee joint prosthesis during movement, and the patient satisfaction is high.

[0041] like Figure 2 and Figure 3 As shown, the medial fossa 110 is used as an example. The elliptical outlines of the multiple concave surfaces 101 in the medial fossa 110 are spaced apart in the anterior-posterior direction of the knee liner 100. The major axis of the elliptical outlines extends in the anterior-posterior direction, while the minor axis of the elliptical outlines extends in the lateral direction. This increases the contact area between the medial condyle of the femoral prosthesis and the medial fossa 110 of the knee liner 100. As the femoral prosthesis flexes with knee joint movement, the medial condyle can shift in the anterior-posterior direction to mate with concave surfaces 101 at different locations in the medial fossa 110. This mimics the kinematic characteristics of a natural knee joint, allowing patients to forget about joint replacement.

[0042] The knee liner 100 of the present invention utilizes the aforementioned structural design for the medial fossa 110, achieving a quasi-medial pivot concept. This structure aligns with the kinematics of the human knee joint. The medial pivot design mimics the natural knee's motion characteristics, particularly its flexion-centered motion around the medial fossa 110. This design not only improves knee stability but also enhances patient satisfaction.

[0043] Alternatively, as Figure 1 As shown, the outer contour of the concave surface 101 in the medial fossa 110 is larger than the outer contour of the concave surface 101 in the lateral fossa 120. It can be appreciated that the contact area between the concave surface 101 of the medial fossa 110 and the medial condyle is greater than the contact area between the concave surface 101 of the lateral fossa 120 and the lateral condyle. This provides a greater displacement of the articular surface of the medial condyle. When the articular surface of the medial condyle undergoes anterior-posterior displacement, it can contact different concave surfaces 101 of the medial fossa 110, thereby avoiding stress concentration. The knee liner 100 of this embodiment of the present invention provides a high contact area, simulates natural knee joint motion, preserves more bone, and reduces the incidence of joint instability, significantly improving the effectiveness of knee replacement surgery and patient satisfaction.

[0044] According to the anatomical feature of the human meniscus that the inner side is larger than the outer side, the contact surface of the concave cavity in the medial fossa 110 of the present invention is larger than the contact surface of the concave cavity in the lateral fossa 120, thereby providing a larger displacement for the articular surface of the medial condyle. The articular surface of the medial condyle is appropriately displaced so as to contact the concave surface 101 at different positions of the medial fossa 110.

[0045] Alternatively, as Figure 2 and Figure 3 As shown, in the medial fossa 110, the minor axes of the ellipses of the outer peripheral contours of the multiple concave surfaces 101 are of the same size. Therefore, when the articular surface of the medial condyle undergoes anterior-posterior displacement and contacts different concave surfaces 101 of the medial fossa 110, the contact stability between the medial condyle and the medial fossa 110 is ensured, allowing the patient to forget about the joint replacement, thereby improving patient satisfaction.

[0046] like Figure 4 and Figure 5 As shown, in the lateral fossa 120, the minor axes of the ellipses of the outer peripheral contours of the multiple concave surfaces 101 are of the same size. Therefore, when the articular surface of the lateral condyle undergoes anterior-posterior displacement and contacts different concave surfaces 101 of the lateral fossa 120, the stability of the contact between the lateral condyle and the lateral fossa 120 is ensured, allowing the patient to forget about the joint replacement, thereby improving patient satisfaction.

[0047] In some embodiments, as Figure 2 and Figure 3 As shown, there are at least three concave surfaces 101 in the medial fossa 110, and the elliptical centers of the three concave surfaces 101 are spaced apart along the anterior-posterior direction of the knee joint liner 100. For example, there may be three, four, five or six concave surfaces 101 in the medial fossa 110.

[0048] Preferably, there are at least six concave surfaces 101 in the medial fossa 110 .

[0049] Specifically, if Figure 2 and Figure 3 As shown, in the medial fossa 110, the 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. The intersection of the median coronal plane of the knee joint liner 100 and the sagittal plane passing through the lowest point of the medial fossa 110 constitutes the ellipse center O1 of the first medial concave surface 1011, the ellipse center O2 of the second medial concave surface 1012 and the ellipse center O3 of the third medial concave surface 1013 are arranged on the front side of the ellipse center O1 of the first medial concave surface 1011, and the ellipse center O4 of the fourth medial concave surface 1014 and the ellipse center O5 of the fifth medial concave surface 1015 are arranged on the back side of the ellipse center O1 of the first medial concave surface 1011.

[0050] In other words, the ellipse center O3 of the third inner concave surface 1013, the ellipse center O2 of the second inner concave surface 1012, the ellipse center O1 of the first inner concave surface 1011, the ellipse center O4 of the fourth inner concave surface 1014 and the ellipse center O5 of the fifth inner concave surface 1015 are arranged in sequence from front to back.

[0051] The inventors of this application have discovered through experimental research that when the concave surfaces 101 in the medial fossa 110 adopt the above-mentioned number and arrangement, the stability of the contact between the medial condyle and the medial fossa 110 can be ensured, and it is closer to the movement principle of the natural knee joint, which is conducive to enhancing patient satisfaction.

[0052] Alternatively, as Figure 4 and Figure 5 As shown, there are at least two concave surfaces 101 in the lateral fossa 120, and the two concave surfaces 101 are spaced apart along the front-back direction of the knee joint liner 100. For example, there may be two, three, four, five or six concave surfaces 101 in the lateral fossa 120.

[0053] Specifically, if Figure 4 and Figure 5 As shown, 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. The intersection of the median coronal plane of the knee joint liner 100 and the sagittal plane passing through the lowest point of the lateral fossa 120 constitutes the ellipse center P1 of the first lateral concave surface 1016, and the ellipse center P2 of the second lateral concave surface 1017 and the ellipse center P3 of the third lateral concave surface 1018 are respectively arranged on the front and back sides of the ellipse center P1 of the first lateral concave surface 1016.

[0054] In other words, the ellipse center P2 of the second outer concave surface 1017 , the ellipse center P1 of the first outer concave surface 1016 , and the ellipse center P3 of the third outer concave surface 1018 are arranged in sequence from front to back.

[0055] The inventors of this application have discovered through experimental research that when the concave surfaces 101 in the lateral fossa 120 adopt the above-mentioned number and arrangement, the stability of the contact between the lateral condyle and the lateral fossa 120 can be ensured, and it is closer to the movement principle of the natural knee joint, which is conducive to enhancing patient satisfaction.

[0056] As can be appreciated, the aforementioned structural arrangement of the knee liner 100 maximizes the contact area between the femoral condyle and the liner in both the sagittal and coronal planes. Specifically, the contact area between the medial condyle and the medial fossa 110 exceeds 97%, while the contact area between the lateral condyle and the lateral fossa 120 exceeds 89%. Furthermore, this design reduces wear on the polyethylene prosthesis, avoiding point contact and stress concentration, thereby significantly extending the prosthesis' lifespan, reducing the incidence of joint instability, and improving the stability of the knee prosthesis during movement.

[0057] Alternatively, as Figure 3 As shown, in the medial socket 110 , the outer peripheral contour of the concave surface 101 has a dimension A1 along the left-right direction of the knee joint liner 100 , wherein 20 mm ≤ A1 ≤ 40 mm. For example, A1 can be 20 mm, 25 mm, 30 mm, 35 mm, or 40 mm.

[0058] In the medial socket 110 , the outer peripheral contour of the concave surface 101 has a dimension B1 along the anterior-posterior direction of the knee joint liner 100 , wherein 38 mm ≤ B1 ≤ 52 mm. For example, B1 may be 38 mm, 42 mm, 45 mm, 48 mm, 50 mm, or 52 mm.

[0059] The inventors of this application have discovered through experimental research that when the contour of the concave surface 101 in the medial fossa 110 adopts the above-mentioned parameter range, it can ensure that the contact area between the medial condyle and the medial fossa 110 is larger during movement, and the stability during movement is higher, which is closer to the movement principle of the natural knee joint and is conducive to enhancing patient satisfaction.

[0060] Alternatively, as Figure 5 As shown, in the lateral socket 120, the outer peripheral contour of the concave surface 101 along the left-right direction of the knee joint liner 100 has a dimension A2, wherein 18 mm ≤ A2 ≤ 38 mm. For example, A2 can be 18 mm, 20 mm, 25 mm, 30 mm, 35 mm, or 38 mm.

[0061] In the lateral socket 120 , the outer peripheral contour of the concave surface 101 has a dimension B2 along the anterior-posterior direction of the knee joint liner 100 , wherein 35 mm ≤ B2 ≤ 50 mm. For example, B2 may be 35 mm, 38 mm, 42 mm, 45 mm, 48 mm, or 50 mm.

[0062] The inventors of this application have discovered through experimental research that when the contour of the concave surface 101 in the lateral fossa 120 adopts the above-mentioned parameter range, it can ensure that the contact between the lateral condyle and the lateral fossa 120 is more stable during movement, and the matching degree between the lateral condyle and the lateral fossa 120 is better, which is closer to the movement principle of the natural knee joint, and is conducive to enhancing patient satisfaction.

[0063] Alternatively, as Figure 1As shown, the distance between the midsagittal plane of the knee liner 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 can be 20 mm, 22 mm, 24 mm, 26 mm, 28 mm, or 30 mm.

[0064] like Figure 1 As shown, the distance between the median sagittal plane of the knee liner 100 and the sagittal plane passing through the lowest point of the lateral fossa 120 is L2, wherein 20 mm ≤ L2 ≤ 30 mm. For example, L2 can be 20 mm, 22 mm, 24 mm, 26 mm, 28 mm, or 30 mm.

[0065] The inventors of the present application have discovered through experimental research that when the medial fossa 110 and the lateral fossa 120 of the knee liner 100 are arranged in the above-mentioned manner, the wear between the knee liner 100 and the femoral prosthesis can be slowed down, and the probability of restricted joint movement is reduced, which is beneficial to improving the stability of the knee prosthesis during movement, and the patient satisfaction is high.

[0066] Alternatively, as Figure 3 As shown, in the medial fossa 110, the distance between the ellipse centers of each two adjacent concave surfaces 101 along the anterior-posterior direction of the knee joint liner 100 is equal. For example, the distance between the ellipse center O3 of the third medial concave surface 1013 and the ellipse center O2 of the second medial concave surface 1012 is equal to the distance between the ellipse center O1 of the first medial concave surface 1011 and the ellipse center O2 of the second medial concave surface 1012. The distance between the ellipse center O5 of the fifth medial concave surface 1015 and the ellipse center O4 of the fourth medial concave surface 1014 is equal to the distance between the ellipse center O1 of the first medial concave surface 1011 and the ellipse center O4 of the fourth medial concave surface 1014. This ensures more stable contact between the medial condyle and the medial fossa 110 during movement, better matching the medial condyle and the medial fossa 110, and more closely aligning with the motion principles of the natural knee joint, thereby enhancing patient satisfaction.

[0067] Alternatively, as Figure 5 As shown, in the lateral fossa 120, the ellipse centers of each adjacent concave surface 101 are spaced equally apart along the anterior-posterior direction of the knee joint liner 100. In other words, the distance between the ellipse center P2 of the second lateral concave surface 1017 and the ellipse center P1 of the first lateral concave surface 1016 is equal to the distance between the ellipse center P3 of the third lateral concave surface 1018 and the ellipse center P1 of the first lateral concave surface 1016. This ensures more stable contact between the lateral condyle and the lateral fossa 120 during movement, better matching the lateral condyle and lateral fossa 120, and more closely resembling the motion principles of a natural knee joint, thereby enhancing patient satisfaction.

[0068] Alternatively, as Figure 3As shown, in the medial fossa 110 , the distance between the ellipse centers of two adjacent concave surfaces 101 along the anterior-posterior direction of the knee joint pad 100 is C1, where 1 mm ≤ C1 ≤ 2 mm. For example, C1 can be 1 mm, 1.5 mm, or 2 mm.

[0069] like Figure 4 As shown, in the lateral fossa 120, the distance between the ellipse centers of two adjacent concave surfaces 101 along the anterior-posterior direction of the knee joint pad 100 is C2, where 2mm≤C2≤4mm. For example, C2 can be 2mm, 2.5mm, 3mm, or 4mm.

[0070] During normal human activity, flexion is accompanied by appropriate internal and external rotation. When the knee joint is initially internally rotated, the articular surface of the lateral condyle initially contacts the first lateral concave surface 1016, and then the articular surface of the lateral condyle moves forward, and the articular surface of the lateral condyle gradually contacts the second lateral concave surface 1017. At this time, the articular surface of the lateral condyle slowly moves forward by approximately 2-4 mm. At the same time, when the knee joint is initially internally rotated, the articular surface of the medial condyle initially contacts the first medial concave surface 1011, and then the articular surface of the medial condyle moves backward, and the articular surface of the medial condyle gradually contacts the fourth medial concave surface 1014. At this time, the articular surface of the medial condyle slowly moves backward by approximately 1 mm.

[0071] The movement of the femoral prosthesis described above can easily cause patients to forget about the joint replacement, in order to achieve a quasi-medial pivot concept. This structure is consistent with the kinematics of the human knee joint. The medial pivot motion design mimics the movement characteristics of the natural knee joint, which not only improves the stability of the knee joint, but also enhances patient satisfaction.

[0072] A knee joint prosthesis according to another embodiment of the present invention includes a femoral prosthesis and a knee joint liner 100 . The femoral prosthesis includes a medial condyle and a lateral condyle. The knee joint liner 100 is the knee joint liner 100 of the present invention. The medial condyle cooperates with a medial fossa 110 , and the lateral condyle cooperates with a lateral fossa 120 .

[0073] According to the knee joint prosthesis of the embodiment of the present invention, since the outer peripheral contour of the concave surface 101 is elliptical, and the elliptical centers of the multiple concave surfaces 101 are arranged at intervals along the anterior-posterior direction of the knee joint pad 100, when the knee joint is in different flexion angles, the femoral prosthesis can contact the concave surfaces 101 at different positions to simulate the movement of the natural knee joint. On the one hand, the contact area between the knee joint pad 100 and the femoral prosthesis is increased, and on the other hand, the probability of joint movement being restricted can be reduced, which is conducive to improving the stability of the knee joint prosthesis during movement, and the patient satisfaction is high.

[0074] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0075] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0076] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0077] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0078] In the present invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent.

[0079] Although the above embodiments have been shown and described, it is understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those skilled in the art are all within the scope of protection of the present invention.

Claims

1. A knee joint pad, characterized in that: The knee liner comprises a medial fossa and a lateral fossa, wherein at least one of the medial fossa and the lateral fossa has a plurality of ellipsoidal concave surfaces, wherein in a projection plane perpendicular to the thickness direction of the knee liner, the outer peripheral contour of the concave surface is an ellipse, the major axis of the ellipse extends along the anterior-posterior direction of the knee liner, and the minor axis of the ellipse extends along the lateral direction of the knee liner, and the ellipse centers of the plurality of concave surfaces are arranged at intervals along the anterior-posterior direction of the knee liner; In the medial fossa, the concave surfaces include 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; the intersection of the median coronal plane of the knee joint liner and the sagittal plane passing through the lowest point of the medial fossa constitutes the ellipse center of the first medial concave surface; the ellipse centers of the second and third medial concave surfaces are arranged anterior to the ellipse center of the first medial concave surface; and the ellipse centers of the fourth and fifth medial concave surfaces are arranged posterior to the ellipse center of the first medial concave surface. And / or, in the lateral fossa, the concave surface includes a first lateral concave surface, a second lateral concave surface and a third lateral concave surface, the intersection of the median coronal plane of the knee joint pad and the sagittal plane passing through the lowest point of the lateral fossa constitutes the ellipse center of the first lateral concave surface, and the ellipse centers of the second lateral concave surface and the ellipse centers of the third lateral concave surface are respectively arranged on the front and back sides of the ellipse center of the first lateral concave surface.

2. The knee joint pad according to claim 1, characterized in that In the medial fossa, the minor axes of the ellipses of the outer peripheral contours of the plurality of concave surfaces are of the same size; And / or, in the lateral fossa, the minor axes of the ellipses of the outer peripheral contours of the plurality of concave surfaces have the same size.

3. The knee joint pad according to claim 1, wherein An outer peripheral contour of the concave surface in the medial fossa is larger than an outer peripheral contour of the concave surface in the lateral fossa.

4. The knee joint pad according to claim 1, wherein In the medial fossa, there are at least three concave surfaces, and the elliptical centers of the three concave surfaces are arranged at intervals along the front-back direction of the knee joint pad; And / or, in the lateral socket, there are at least two concave surfaces, and the two concave surfaces are arranged at intervals along the front-back direction of the knee joint pad.

5. The knee joint pad according to claim 1, wherein In the medial fossa, the dimension of the outer peripheral contour of the concave surface along the left-right direction of the knee joint pad is A1, wherein 20 mm ≤ A1 ≤ 40 mm; and / or, in the medial fossa, a dimension of the outer peripheral contour of the concave surface along the anterior-posterior direction of the knee joint liner is B1, wherein 38 mm ≤ B1 ≤ 52 mm; and / or, in the lateral socket, a dimension of the outer peripheral contour of the concave surface along the left-right direction of the knee joint pad is A2, wherein 18 mm ≤ A2 ≤ 38 mm; And / or, in the lateral socket, a dimension of an outer peripheral contour of the concave surface along the anterior-posterior direction of the knee joint pad is B2, wherein 35 mm ≤ B2 ≤ 50 mm.

6. The knee joint pad according to claim 1, wherein: The distance between the median sagittal plane of the knee joint pad and the sagittal plane passing through the lowest point of the medial fossa is L1, wherein 20 mm ≤ L1 ≤ 30 mm; And / or, a distance between the median sagittal plane of the knee joint pad and a sagittal plane passing through the lowest point of the lateral fossa is L2, wherein 20 mm ≤ L2 ≤ 30 mm.

7. The knee joint pad according to claim 1, wherein: In the medial fossa, the distances between the centers of the ellipses of each of the two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad are equal; And / or, in the lateral fossa, the distances between the centers of the ellipses of each two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad are equal.

8. The knee joint pad according to claim 1, wherein In the medial fossa, the distance between the centers of the ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad is C1, wherein 1 mm ≤ C1 ≤ 2 mm; And / or, in the lateral fossa, the distance between the centers of the ellipses of two adjacent concave surfaces along the anterior-posterior direction of the knee joint pad is C2, wherein 2mm≤C2≤4mm.

9. A knee joint prosthesis, characterized in that: include: a femoral prosthesis comprising a medial condyle and a lateral condyle; A knee joint pad, wherein the knee joint pad is the knee joint pad according to any one of claims 1 to 8, wherein the medial condyle cooperates with the medial fossa, and the lateral condyle cooperates with the lateral fossa.

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