Tibial prosthesis and ankle joint prosthesis

Abstract

The tibia prosthesis is used for being installed at the far end of a tibia, the tibia prosthesis is provided with a first inner side face and a first outer side face, and the first inner side face and the first outer side face are arranged on the two sides of the median sagittal plane of the tibia prosthesis respectively. In a projection orthogonal to the vertical direction of the tibia prosthesis, the outlines of the first inner side face and the first outer side face are both curves and protrude in the direction away from the median sagittal plane. The tibia prosthesis is reasonable in structural design, the tibia prosthesis can be highly matched with the anatomical structure of the human body, the osteotomy amount is reduced, the risk that the prosthesis collides with the tibia in the moving process is reduced, the problem of pain of a patient is solved, the service life of the prosthesis is prolonged, and the cost is reduced. The success rate of the ankle joint replacement operation and the postoperative life quality of a patient are obviously improved.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a tibial prosthesis and an ankle joint prosthesis. Background Technology

[0002] In ankle replacement surgery, the design of the ankle prosthesis is crucial. Currently, commonly used tibial prostheses have parallel surfaces on both the inner and outer sides. However, this design differs significantly from the anatomical structure of the normal ankle mortise. The normal ankle mortise is not rectangular, and this mismatch can easily lead to fractures of the medial and lateral edges of the tibia during osteotomy. Furthermore, the ankle mortise formed by vertical osteotomy based on a parallel surface design will generate impact during internal and external rotation and eversion movements of the talus prosthesis, causing not only patient pain but also accelerating prosthesis wear and shortening its lifespan. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention propose a tibial prosthesis with a reasonable structural design that allows the tibial prosthesis to closely match the human anatomical structure, reducing the amount of bone resection, lowering the risk of the prosthesis impacting the tibia during activity, helping to solve patient pain problems, extending the service life of the prosthesis, and significantly improving the success rate of ankle replacement surgery and the postoperative quality of life of patients.

[0005] An embodiment of the present invention also proposes an ankle joint prosthesis.

[0006] The tibial prosthesis of the present invention is used for installation on the distal end of the tibia. The tibial prosthesis has a first medial surface and a first lateral surface. The first medial surface and the first lateral surface are respectively arranged on both sides of the midsagittal plane of the tibial prosthesis. In the projection orthogonal to the vertical direction of the tibial prosthesis, the contours of the first medial surface and the first lateral surface are both curved and protrude in a direction away from the midsagittal plane.

[0007] According to an embodiment of the present invention, the tibial prosthesis has a first medial surface and a first lateral surface respectively arranged on both sides of the midsagittal plane of the tibial prosthesis. In the projection orthogonal to the vertical direction of the tibial prosthesis, the contours of the first medial surface and the first lateral surface are both curved and protrude in a direction away from the midsagittal plane. This allows the tibial prosthesis to fit closely to the anatomical structure of the human tibia, reducing the amount of osteotomy, lowering the risk of the prosthesis impacting the tibia during activity, helping to solve the patient's pain problem, prolonging the service life of the prosthesis, and significantly improving the success rate of ankle replacement surgery and the patient's postoperative quality of life.

[0008] In some embodiments, the curve is constructed as part of an elliptical profile.

[0009] In some embodiments, in a projection orthogonal to the vertical direction of the tibial prosthesis, the contour lines of the first inner surface and the first outer surface lie on the same elliptical contour line.

[0010] In some embodiments, the major axis of the elliptical contour is a, and the minor axis of the elliptical contour is b, wherein 30mm≤a≤80mm, and 20mm≤b≤40mm.

[0011] In some embodiments, the center of the elliptical outline is located at the junction of the midsagittal and midcoronal planes of the tibial prosthesis.

[0012] An ankle joint prosthesis according to an embodiment of the present invention includes: a tibial prosthesis and a talus prosthesis, wherein the tibial prosthesis is the tibial prosthesis described in any one of the embodiments of the present invention, and the talus prosthesis is used in conjunction with the tibial prosthesis.

[0013] According to an embodiment of the present invention, the ankle joint prosthesis has a first medial surface and a first lateral surface respectively arranged on both sides of the midsagittal plane of the tibial prosthesis. In the projection orthogonal to the vertical direction of the tibial prosthesis, the contours of the first medial surface and the first lateral surface are both curved and protrude in a direction away from the midsagittal plane. This allows the tibial prosthesis to fit closely to the anatomical structure of the human tibia, reducing the amount of osteotomy, lowering the risk of the prosthesis impacting the tibia during activity, helping to solve the patient's pain problem, prolonging the service life of the prosthesis, and significantly improving the success rate of ankle joint replacement surgery and the patient's postoperative quality of life.

[0014] In some embodiments, the talus prosthesis has a second inner surface and a second outer surface, which are respectively arranged on both sides of the midsagittal plane of the talus prosthesis. In the projection orthogonal to the vertical direction of the talus prosthesis, the contours of the second inner surface and the second outer surface are both curved and protrude in a direction away from the midsagittal plane.

[0015] In some embodiments, in a projection orthogonal to the vertical direction of the talus prosthesis, at least a portion of the contour line of the first inner surface coincides with the contour line of the second inner surface, and at least a portion of the contour line of the first outer surface coincides with the contour line of the second outer surface.

[0016] In some embodiments, in a projection orthogonal to the vertical direction of the talus prosthesis, the contour lines of the second inner surface and the second outer surface lie on the same elliptical contour line.

[0017] In some embodiments, the ankle prosthesis further includes a pad that is mounted on the tibial prosthesis and the talus prosthesis slides in conjunction with the pad. Attached Figure Description

[0018] Figure 1 This is a three-dimensional view of the ankle joint prosthesis according to an embodiment of the present invention.

[0019] Figure 2 This is a partial view of the tibial prosthesis according to an embodiment of the present invention.

[0020] Figure 3 This is an assembly diagram of the tibial prosthesis and tibia according to an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the distal tibia in an embodiment of the present invention.

[0022] Figure 5 This is a schematic diagram of the talus prosthesis according to an embodiment of the present invention.

[0023] Figure 6 This is an assembly diagram of the talus prosthesis and tibia according to an embodiment of the present invention.

[0024] Figure label: 1. Tibial prosthesis; 11. First medial surface; 12. First lateral surface; 2. Talus prosthesis; 21. Second medial surface; 22. Second lateral surface; 3. Padding; 4. Tibia; 41. Ankle mortise; S, elliptical outline; P, midsagittal plane. Detailed Implementation

[0025] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0026] In the fields of anatomy and medical devices, directions and planes such as internal, external, anterior, posterior, distal, proximal, sagittal, coronal, and cross-section have specific meanings and are well known to those skilled in the art. Unless otherwise specified, these terms refer to the meanings generally accepted by those skilled in the art.

[0027] Typically, when describing the human body, joints, or prostheses, three types of cross-sections are involved: the sagittal plane, the coronal plane, and the cross-section. The sagittal plane is a longitudinal section that divides the human body or joint into left and right parts along the anterior-posterior direction. The median sagittal plane, passing through the center of the human body, divides the body into two equal parts. The coronal plane is a longitudinal section that divides the human body or joint into anterior and posterior parts along the lateral direction. The coronal plane is perpendicular to the sagittal plane. The cross-section is a plane parallel to the ground that divides the human body or joint into upper and lower parts. The cross-section is perpendicular to both the coronal and sagittal planes.

[0028] Typically, when describing the human body, joints, or prostheses, three different directions are involved: distal, medial, and posterior. The distal end refers to the end of the body or joint relatively far from the torso. The proximal end refers to the side of the body or joint relatively close to the torso, specifically the side relatively close to the midsagittal plane. The lateral end refers to the side relatively far from the midsagittal plane. The anterior end refers to the end in the sagittal plane relatively close to the abdomen. The posterior end refers to the end in the sagittal plane relatively close to the back.

[0029] The following is a reference appendix. Figures 1 to 6 The tibial prosthesis 1 and the ankle joint prosthesis of the present invention are described in embodiments.

[0030] like Figures 1 to 3 As shown, the tibial prosthesis 1 of this embodiment is used to be installed at the distal end of the tibia 4. The tibial prosthesis 1 has a first medial surface 11 and a first lateral surface 12. The first medial surface 11 and the first lateral surface 12 are respectively arranged on both sides of the midsagittal plane P of the tibial prosthesis 1. In the projection orthogonal to the vertical direction of the tibial prosthesis 1, the contours of the first medial surface 11 and the first lateral surface 12 are both curved and protrude in a direction away from the midsagittal plane P.

[0031] According to an embodiment of the present invention, the tibial prosthesis 1 has a first medial surface 11 and a first lateral surface 12 respectively arranged on both sides of the midsagittal plane P of the tibial prosthesis 1. In the projection orthogonal to the vertical direction of the tibial prosthesis 1, the contours of the first medial surface 11 and the first lateral surface 12 are both curved and protrude in a direction away from the midsagittal plane P. This allows the tibial prosthesis 1 to fit closely with the anatomical structure of the human tibia 4, which can reduce the amount of osteotomy, reduce the risk of the prosthesis impacting the tibia 4 during activity, help solve the patient's pain problem, extend the service life of the prosthesis, and significantly improve the success rate of ankle replacement surgery and the patient's postoperative quality of life.

[0032] In other words, the tibial prosthesis 1 with the above-mentioned structure is adapted to the anatomical shape of the normal ankle mortise groove 41. During the actual tibial osteotomy, the doctor can cut out the ankle mortise groove 41 that matches the tibial prosthesis 1, and then accurately install the tibial prosthesis 1 of the corresponding shape into the groove. This can reduce the amount of osteotomy. At the same time, when the talus prosthesis 2 performs various complex activities, such as internal and external rotation and inversion, it greatly reduces the risk of impact on the ankle mortise groove 41, reduces patient pain, and extends the service life of the prosthesis.

[0033] Optionally, the curve is constructed as part of an elliptical contour line S. That is, the contour lines of the first inner surface 11 and the first outer surface 12 are elliptical arcs. This allows the tibial prosthesis 1 to be further adapted to the human tibia 4, reducing the amount of osteotomy required on the autologous tibia 4, preserving healthy bone tissue to the greatest extent, and laying a solid foundation for stable bone healing after surgery.

[0034] like Figure 2 As shown, in the projection orthogonal to the vertical direction of the tibial prosthesis 1, the contour lines of the first medial surface 11 and the first lateral surface 12 lie on the same elliptical contour line S. This allows the medial and lateral contours of the tibial prosthesis 1 to be approximately elliptical in shape. With the center of the ellipse of the tibial prosthesis 1 as the reference, which is the center of the medullary canal of the tibia 4, the amount of osteotomy of the autologous tibia 4 is effectively reduced. At the same time, when the talus prosthesis 2 performs various complex activities, such as internal and external rotation and inversion / eversion, the risk of impact on the ankle mortise groove 41 is greatly reduced, patient pain is alleviated, and the service life of the prosthesis is extended.

[0035] Optionally, the major axis of the elliptical contour S is a, and the minor axis of the elliptical contour S is b, where 30mm≤a≤80mm and 20mm≤b≤40mm.

[0036] 'a' can be selected between 30mm and 80mm. For example, 'a' can be 30mm, 40mm, 50mm, 60mm, 70mm, or 80mm.

[0037] b can be selected between 20mm and 40mm. For example, b can be 20mm, 30mm, or 40mm.

[0038] The tibial prosthesis 1 of the present invention is designed with the above-mentioned parameters for the major axis a and minor axis b of the elliptical contour S, which can be adapted to the anatomical shape of the normal ankle mortise groove 41. During the actual tibial osteotomy, the doctor can cut out the ankle mortise groove 41 that matches the tibial prosthesis 1, and then accurately install the tibial prosthesis 1 of the corresponding shape in the groove. This can reduce the amount of osteotomy. At the same time, when the talus prosthesis 2 performs various complex activities, such as internal and external rotation and inversion, it greatly reduces the risk of impact on the ankle mortise groove 41, reduces patient pain, and extends the service life of the prosthesis.

[0039] Optionally, the center of the elliptical outline S is located at the junction of the midsagittal plane P and the midcoronal plane of the tibial prosthesis 1. Using the center of the ellipse of the tibial prosthesis 1 as a reference, which is also the center of the medullary canal of the tibia 4, effectively reduces the amount of osteotomy required on the autologous tibia 4. Simultaneously, during various complex activities of the talus prosthesis 2, such as internal and external rotation and eversion / inversion, it significantly reduces the risk of impact on the ankle mortise groove 41, alleviates patient pain, and extends the prosthesis's lifespan.

[0040] like Figures 1 to 6 As shown, the ankle joint prosthesis of the present invention includes: a tibial prosthesis 1 and a talus prosthesis 2, wherein the tibial prosthesis 1 is the tibial prosthesis 1 of the present invention, and the talus prosthesis 2 is fitted with the tibial prosthesis 1.

[0041] According to an embodiment of the present invention, the ankle joint prosthesis, since the first medial surface 11 and the first lateral surface 12 are respectively arranged on both sides of the midsagittal plane P of the tibial prosthesis 1, in the projection orthogonal to the vertical direction of the tibial prosthesis 1, the contours of the first medial surface 11 and the first lateral surface 12 are both curved and protrude in a direction away from the midsagittal plane P. This allows the tibial prosthesis 1 to fit closely with the anatomical structure of the human tibia 4, reducing the amount of osteotomy, reducing the risk of the prosthesis impacting the tibia 4 during activity, which helps to solve the patient's pain problem, prolongs the service life of the prosthesis, and significantly improves the success rate of ankle joint replacement surgery and the patient's postoperative quality of life.

[0042] Optionally, such as Figure 5 As shown, the talus prosthesis 2 has a second inner surface 21 and a second outer surface 22. The second inner surface 21 and the second outer surface 22 are respectively arranged on both sides of the midsagittal plane P of the talus prosthesis 2. In the projection orthogonal to the vertical direction of the talus prosthesis 2, the contours of the second inner surface 21 and the second outer surface 22 are both curved and protrude in the direction away from the midsagittal plane P.

[0043] Therefore, when the talus prosthesis 2 impacts the tibia 4 during internal and external rotation and eversion movements, the curved inner and / or outer surfaces can gradually come into contact with the tibia 4, so that the impact force can be distributed to the contact surfaces of different positions of the talus prosthesis 2. This changes the contact pattern with the inner and outer sides of the tibia 4, avoids direct hard collision between the talus prosthesis 2 and the tibia 4, and greatly reduces the risk of wear, pain and inflammation caused by the impact between the talus prosthesis 2 and the tibia 4. This is beneficial to improving the stability of the talus prosthesis 2 implantation and is conducive to the patient's postoperative recovery.

[0044] Optionally, such as Figure 2 and Figure 5As shown, in a projection orthogonal to the vertical direction of the talus prosthesis 2, at least a portion of the contour line of the first medial surface 11 coincides with the contour line of the second medial surface 21, and at least a portion of the contour line of the first lateral surface 12 coincides with the contour line of the second lateral surface 22. This allows the medial and lateral contours of the talus prosthesis 2 to match the medial and lateral contours of the tibial prosthesis 1. When the human body performs normal dorsiflexion, dorsiflexion, or other activities that result in internal or external rotation or inversion, the medial and lateral shapes of the talus prosthesis 2 are consistent with the medial and lateral shapes of the ankle mortise groove 41, effectively preventing the talus prosthesis 2 from impacting the tibia 4, thus reducing patient pain and extending the prosthesis's lifespan.

[0045] Optionally, such as Figure 5 As shown, in the projection orthogonal to the vertical direction of the talus prosthesis 2, the contour lines of the second medial surface 21 and the second lateral surface 22 lie on the same elliptical contour line S. This allows the medial and lateral contours of the talus prosthesis 2 to be approximately elliptical. With the center of the ellipse of the talus prosthesis 2 as a reference, this reference is aligned with the center of the medullary canal of the tibia 4. This effectively reduces the amount of osteotomy required on the autologous tibia 4. Furthermore, during various complex activities of the talus prosthesis 2, such as internal and external rotation and eversion, it significantly reduces the risk of impact on the ankle mortise groove 41, alleviates patient pain, and extends the lifespan of the ankle joint prosthesis.

[0046] like Figure 1 As shown, the ankle joint prosthesis also includes a pad 3, which is installed on the tibial prosthesis 1, and the talus prosthesis 2 slides in conjunction with the pad 3. The pad 3 can reduce the friction between the tibial prosthesis 1 and the talus prosthesis 2, which helps to extend the service life of the ankle joint prosthesis.

[0047] For example, the tibial prosthesis 1 and the talus prosthesis 2 can be made of metal or bioceramic.

[0048] In the example of this invention, the center of the talus prosthesis 2, the center of the tibia prosthesis 1, and the center of the medullary cavity of the tibia prosthesis 1 are located on the same axis. That is, the multi-center mutual compensation of the ankle joint prosthesis can reduce the impact of the talus prosthesis 2 on the inner and outer sides of the ankle mortise groove 41 during ankle joint movement. Due to this multi-center coaxial concentric and reference design, the risk of impact on the ankle mortise groove 41 during patient movement is reduced. In addition, since the inner and outer sides of the talus prosthesis 2 are designed with an elliptical structure, it can adapt to the structure of the ankle mortise groove 41 and the anatomical shape after talus osteotomy, solving the problem of poor coverage of the talus prosthesis 2. Moreover, the inner and outer sides of the talus prosthesis 2 are consistent with the inner and outer sides of the tibia prosthesis 1, thereby improving the structural stability of the ankle joint.

[0049] The ankle prosthesis of this invention can fundamentally reduce the impact of the talus on the ankle mortise groove 41 during movement, significantly reducing the incidence of postoperative pain, enabling patients to return to normal life more quickly, and significantly extending the lifespan of the prosthesis, reducing the need for revision surgery, and lowering medical costs and suffering for patients. Due to the close fit between the talus prosthesis 2 and the talus osteotomy surface and the precise matching between the tibial prosthesis 1 and the ankle mortise groove 41, the stability of the ankle joint can be significantly enhanced, promoting the full recovery of postoperative joint function and improving the patient's quality of life.

[0050] In the description of this 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," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0051] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0055] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A tibial prosthesis (1), characterized in that, The tibial prosthesis (1) is used to be installed at the distal end of the tibia (4). The tibial prosthesis (1) has a first medial surface (11) and a first lateral surface (12). The first medial surface (11) and the first lateral surface (12) are respectively arranged on both sides of the median sagittal plane (P) of the tibial prosthesis (1). In the projection orthogonal to the vertical direction of the tibial prosthesis (1), the contours of the first medial surface (11) and the first lateral surface (12) are both curved and protrude in a direction away from the median sagittal plane (P).

2. The tibial prosthesis (1) according to claim 1, characterized in that, The curve is constructed as part of an elliptical contour (S).

3. The tibial prosthesis (1) according to claim 2, characterized in that, In a projection orthogonal to the vertical direction of the tibial prosthesis (1), the outline of the first inner surface (11) and the outline of the first outer surface (12) lie on the same elliptical outline (S).

4. The tibial prosthesis (1) according to claim 3, characterized in that, The major axis of the elliptical contour line (S) is a, and the minor axis of the elliptical contour line (S) is b, wherein 30mm≤a≤80mm and 20mm≤b≤40mm.

5. The tibial prosthesis (1) according to claim 3, characterized in that, The center of the elliptical outline (S) is located at the junction of the midsagittal plane (P) and the midcoronal plane of the tibial prosthesis (1).

6. An ankle joint prosthesis, characterized in that, include: Tibial prosthesis (1), wherein the tibial prosthesis (1) is the tibial prosthesis (1) according to any one of claims 1-5; A talus prosthesis (2) is used in conjunction with a tibial prosthesis (1).

7. The ankle joint prosthesis according to claim 6, characterized in that, The talus prosthesis (2) has a second inner surface (21) and a second outer surface (22). The second inner surface (21) and the second outer surface (22) are respectively arranged on both sides of the midsagittal plane (P) of the talus prosthesis (2). In the projection orthogonal to the vertical direction of the talus prosthesis (2), the contours of the second inner surface (21) and the second outer surface (22) are both curved and protrude in a direction away from the midsagittal plane (P).

8. The ankle joint prosthesis according to claim 7, characterized in that, In a projection orthogonal to the vertical direction of the talus prosthesis (2), at least a portion of the outline of the first inner surface (11) coincides with the outline of the second inner surface (21), and at least a portion of the outline of the first outer surface (12) coincides with the outline of the second outer surface (22).

9. The ankle joint prosthesis according to claim 7, characterized in that, In a projection orthogonal to the vertical direction of the talus prosthesis (2), the outline of the second inner surface (21) and the outline of the second outer surface (22) lie on the same elliptical outline (S).

10. The ankle joint prosthesis according to any one of claims 6-9, characterized in that, The ankle joint prosthesis also includes a pad (3), which is installed on the tibial prosthesis (1), and the talus prosthesis (2) slides in conjunction with the pad (3).

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