Joint replacement prosthesis

Abstract

The present invention provides a joint replacement prosthesis, comprising: a replacement base; a fixing column, the fixing column having a first end and a second end, the first end being connected to the replacement base, and the cross section of the fixing column gradually increasing from the first end to the second end. The technical solution of the present application can effectively solve the problem of instability and easy loosening of the joint replacement prosthesis during use in the related art.

Description

Technical Field

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

[0002] Partial full-thickness defects and deformed necrosis of the articular cartilage surface caused by trauma, osteochondritis exfoliativa, and joint degeneration are one of the more common joint diseases. Articular cartilage, whose structure includes uncalcified hyaline cartilage on the surface and calcified cartilage in the deep layer, is smooth and elastic, and can absorb shocks and buffer stress to the maximum extent, playing an important role in distributing the pressure applied to the entire joint surface and protecting the integrity of the subchondral bone. Since articular cartilage has no blood vessels, nerves, or lymph supply, once damaged, it is difficult to heal itself, and its absorption of force is reduced, which can lead to progressive aggravation of joint damage and degeneration.

[0003] Therefore, research on articular surface defects has become a frontier and hot topic in the field of osteoarthritis, and people have also made many attempts to repair articular surfaces. At present, clinical treatments for articular cartilage injuries generally include microfracture, autologous cartilage transplantation, autologous chondrocyte transplantation, mosaic plasty, etc.

[0004] Microfracture is a minimally invasive surgery performed with an arthroscopic approach. It drills into the subchondral bone marrow space through the damaged area of ​​the articular cartilage layer to stimulate the body's spontaneous repair response, but the healing response is highly variable and non-reproducible, and fibrous tissue is easily formed. The principle of autologous cartilage transplantation is to insert several or more pieces of (autologous) transplant materials into the defect, mainly cylindrical plugs of osteochondral tissue drilled from non-load-bearing areas, and press-fit them into the damaged area side by side, which creates the possibility of degeneration of other joint parts and may cause loss of vitality of cartilage tissue during the transplantation process. Autologous chondrocyte transplantation, also known as ACI technology, mainly involves culturing and proliferating the patient's own articular chondrocytes in vitro and then implanting them into the defect of the joint surface. This method requires two surgeries to complete, and the process is long and complicated. While obtaining healthy cartilage, it may increase other lesions in the joint.

[0005] In the related art, a joint replacement prosthesis can be used to replace the damaged area of ​​the articular cartilage layer. The joint replacement prosthesis generally includes a replacement matrix and a fixing column. However, after being implanted for a period of time, the joint replacement prosthesis is prone to rotate or loosen relative to the patient's joint. Summary of the invention

[0006] The main purpose of the present invention is to provide a joint replacement prosthesis to solve the problem of instability and easy loosening of the joint replacement prosthesis during use in the related art.

[0007] In order to solve the above problems, the present invention provides a joint replacement prosthesis, including: a replacement base; a fixing column, the fixing column having a first end and a second end, the first end is connected to the replacement base, and the cross-section of the fixing column gradually increases from the first end to the second end.

[0008] Further, the angle a between the generatrix of the side surface of the fixing column and the axis L of the fixing column satisfies: 1°<a<5°.

[0009] Furthermore, a notch extending from the second end to the first end is provided on the fixing column, and the notch divides the fixing column into a plurality of column units.

[0010] Furthermore, the joint replacement prosthesis also includes an osteoinductive structure arranged at the notch.

[0011] Further, the replacement matrix has a spherical outer surface, the surface area of ​​the spherical outer surface is less than or equal to 1 / 3 of the surface area of ​​the sphere where the spherical outer surface is located, and / or the height h of the replacement matrix satisfies: h≤26 mm.

[0012] Further, the replacement matrix includes an outer layer and an inner layer arranged between the outer layer and the fixed column, the outer layer includes an anti-seepage platform bent toward the fixed column and covering the inner layer; or, the replacement matrix includes an outer layer and an inner layer arranged between the outer layer and the fixed column, the outer layer includes an anti-seepage platform protruding from the inner layer along the circumference of the inner layer.

[0013] Furthermore, the replacement matrix further includes a wear-resistant coating disposed on the outer surface of the replacement matrix, and / or the surface roughness of the replacement matrix is ​​less than or equal to 0.1 μm.

[0014] Furthermore, a guide thread is provided on the fixing column, or the fixing column further includes an anti-rotation rib provided on an outer side wall of the fixing column, and the anti-rotation rib extends along the length direction of the fixing column.

[0015] Furthermore, joint replacement prostheses are made of metal or ceramic materials.

[0016] Furthermore, the replacement base and the fixing column are an integrally formed structure.

[0017] By applying the technical solution of the present invention, the joint replacement prosthesis can be implanted into the target bone and directly replace the damaged joint surface of the patient, without obtaining the patient's healthy cartilage for transplantation, and other joint positions will not be lesioned. The joint replacement prosthesis includes a replacement matrix and a fixed column, wherein the replacement matrix can replace the defective joint surface of the patient and form a joint friction pair with the corresponding healthy joint surface to achieve normal joint movement. The first end of the fixed column is connected to the replacement matrix, and the second end of the fixed column is inserted into the damaged joint of the patient to achieve the connection between the joint replacement prosthesis and the patient's bone. Among them, the cross-section of the fixed column gradually increases from the first end to the second end. During implantation, the joint replacement prosthesis is implanted into the damaged position of the patient's joint by external force. After the implantation is completed, since the cross-sectional area of ​​the second end of the fixed column is larger than the cross-sectional area of ​​the first end of the fixed column, the stability of the joint replacement prosthesis is guaranteed, so that the joint replacement prosthesis can be stably connected to the patient's bone. At the same time, the second end of the fixed column will form a mechanical stimulation to the patient's bone, promote the fusion of the fixed column and the patient's bone, and further enhance the stability of the joint replacement prosthesis. Therefore, the technical solution of the present application can effectively solve the problem of instability and easy loosening of joint replacement prostheses during use in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 A schematic cross-sectional view of a first embodiment of a joint replacement prosthesis according to the present invention is shown;

[0020] Figure 2 A schematic cross-sectional view of a second embodiment of a joint replacement prosthesis according to the present invention is shown;

[0021] Figure 3 A schematic cross-sectional view of a third embodiment of a joint replacement prosthesis according to the present invention is shown;

[0022] Figure 4 A schematic cross-sectional view showing a fourth embodiment of a joint replacement prosthesis according to the present invention; and

[0023] Figure 5 A schematic cross-sectional view of a fifth embodiment of a joint replacement prosthesis according to the present invention is shown.

[0024] The above drawings include the following reference numerals:

[0025] 10. Replacement matrix; 11. Outer layer; 111. Anti-seepage platform; 12. Inner layer; 20. Fixing column; 21. Notch; 22. Guide thread; 23. Anti-rotation rib; 24. Porous structure; 30. Osteoinduction structure; L. Axis. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0028] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0029] Figure 1 The cross-sectional schematic diagram of the joint replacement prosthesis according to the first embodiment of the present application is shown, and the joint replacement prosthesis of the first embodiment includes a replacement matrix 10 and a fixing column 20. The fixing column 20 has a first end and a second end, the first end is connected to the replacement matrix 10, and the cross section of the fixing column 20 gradually increases from the first end to the second end.

[0030] By applying the technical solution of the first embodiment, the joint replacement prosthesis can be implanted into the target bone and directly replace the damaged joint surface of the patient, without obtaining the patient's healthy cartilage for transplantation, and other joint positions will not be lesioned. The joint replacement prosthesis includes a replacement matrix 10 and a fixed column 20, wherein the replacement matrix 10 can replace the defective joint surface of the patient and form a joint friction pair with the corresponding healthy joint surface to achieve normal joint movement. The first end of the fixed column 20 is connected to the replacement matrix 10, and the second end of the fixed column 20 is inserted into the damaged joint of the patient to achieve the connection between the joint replacement prosthesis and the patient's bone. Among them, the cross-section of the fixed column 20 gradually increases from the first end to the second end. During implantation, the joint replacement prosthesis is implanted into the damaged joint position of the patient by external force. After the implantation is completed, since the cross-sectional area of ​​the second end of the fixed column 20 is larger than the cross-sectional area of ​​the first end of the fixed column 20, the stability of the joint replacement prosthesis after implantation is guaranteed, so that the joint replacement prosthesis can be firmly connected to the patient's bone. At the same time, the second end of the fixing column 20 will form a mechanical stimulation to the patient's bone, promote the fusion of the fixing column 20 and the patient's bone, and further enhance the stability of the joint replacement prosthesis after implantation. Therefore, the technical solution of the present application can effectively solve the problem of instability and easy loosening of the joint replacement prosthesis during use in the related art.

[0031] like Figure 1 As shown, the angle a between the generatrix on the side of the fixing column 20 and the axis L of the fixing column 20 satisfies: 1°<a<5°. When the angle a≤1°, the angle between the generatrix on the side of the fixing column 20 and the axis L of the fixing column 20 is too small, and the mechanical stimulation to the patient's bone is weak; when the angle a≥5°, the angle between the generatrix on the side of the fixing column 20 and the axis L of the fixing column 20 is too large, which will make it more difficult to implant the joint replacement prosthesis, and may even damage the patient's healthy bone during the implantation process. Therefore, the above-mentioned size setting makes the implantation of the joint replacement prosthesis easier, while at the same time being able to produce a certain mechanical stimulation to the patient's healthy bone, accelerate the fusion process between the joint replacement prosthesis and the patient's bone, and enhance the stability of the joint replacement prosthesis after implantation.

[0032] like Figure 1 As shown, the fixing column 20 is provided with a notch 21 extending from the second end to the first end, and the notch 21 divides the fixing column 20 into a plurality of column units. After the joint replacement prosthesis is implanted for a period of time, the patient's healthy bone can grow into the notch 21, making the connection between the joint replacement prosthesis and the patient's bone more secure. Figure 1 As shown, in this embodiment, the notch 21 divides the fixing column 20 into two column units. In other feasible implementations, the notch can also divide the fixing column into three, four or more column units, as long as the strength requirements of the fixing column can be met.

[0033] like Figure 1 As shown, the replacement matrix 10 has a spherical outer surface, the surface area of ​​the spherical outer surface is less than or equal to 1 / 3 of the surface area of ​​the sphere on which the spherical outer surface is located, and the height h of the replacement matrix 10 satisfies: h≤26mm. The spherical outer surface of the replacement matrix 10 can physiologically adapt to the outer surface of the patient's damaged bone. At the same time, the setting of the above-mentioned dimensions can ensure that there is enough healthy bone at the patient's injured site to maintain the stability of the joint replacement prosthesis. When implanting a joint replacement prosthesis, the upper surface of the joint replacement prosthesis should be slightly lower than the patient's joint surface cartilage layer by a certain distance, and the distance can specifically be 0.5mm, so as to protect the surface cartilage of the contralateral joint that cooperates with the joint.

[0034] like Figure 1 As shown, the fixing column 20 is provided with a guide thread 22. The provision of the guide thread 22 can make the implantation of the joint replacement prosthesis easier, and the joint replacement prosthesis is more stable and less likely to loosen after implantation. At the same time, the guide thread 22 can also form a mechanical stimulation to the patient's healthy bone, promoting the fusion of the fixing column 20 and the patient's bone.

[0035] like Figure 1 As shown, in this embodiment, the replacement matrix 10 includes an outer layer 11 and an inner layer 12 arranged between the outer layer 11 and the fixing column 20, and the outer layer 11 includes an impermeable platform 111 that is bent toward the fixing column 20 and covers the inner layer 12. Specifically, the inner layer has a porous structure, and the porous structure is easy for bone growth, and can be connected with the bone body of the defective part, so as to achieve better bone fusion and improve the connection stability between the joint replacement prosthesis and the patient's bone body. The impermeable platform 111 is bent toward the fixing column 20 and covers the inner layer 12. The impermeable platform 111 is located between the inner layer 12 and the joint friction pair, and can prevent the synovial fluid from penetrating into the patient's subchondral bone through the inner layer 12. In this way, it is ensured that there is sufficient synovial fluid between the joint friction pairs, and at the same time, it can prevent the synovial fluid from penetrating into the patient's subchondral bone and damaging the patient's healthy bone.

[0036] like Figure 1 As shown, the replacement matrix 10 also includes a wear-resistant coating disposed on the outer surface of the replacement matrix 10, and the surface roughness of the replacement matrix 10 is less than or equal to 0.1 μm. Specifically, the above-mentioned wear-resistant coating can be a diamond-like carbon coating (DLC coating), a ceramic coating, a CrN coating, etc. In this way, the replacement matrix 10 has excellent wear resistance, can replace the patient's damaged joint surface, and form a joint friction pair with the joint surface on the opposite side of the patient's damaged joint to achieve normal movement of the joint. The provision of the wear-resistant coating can reduce the friction and wear between the joint surfaces and extend the life of the joint replacement prosthesis.

[0037] In this embodiment, the joint replacement prosthesis is made of metal or ceramic material. Specifically, the metal is a metal with good biocompatibility, and can be a titanium alloy material, a cobalt-chromium alloy, etc. The ceramic material can be a bioactive ceramic material.

[0038] In this embodiment, the replacement base 10 and the fixing column 20 are an integrally formed structure. Specifically, the replacement base 10 and the fixing column 20 can be integrally formed by 3D printing technology, which can avoid the risk of loose assembly due to the use of a split structure.

[0039] Figure 2 A cross-sectional schematic diagram of a joint replacement prosthesis according to Example 2 of the present application is shown. The joint replacement prosthesis of Example 2 differs from Example 1 mainly in that the joint replacement prosthesis of Example 2 also includes a bone induction structure 30 disposed at the notch 21. Specifically, the notch 21 divides the fixed column 20 into a plurality of column units, and an installation area is disposed on the inner surface of the column unit. The bone induction structure 30 is disposed in the installation area. The bone induction structure 30 is an active substance with a biological induction function, and may specifically be a hydrogel, hydroxyapatite, etc. The bone induction structure 30 can promote the patient's bone tissue to fill into the notch 21, and increase the stability of the joint replacement prosthesis after implantation. At the same time, after the joint replacement prosthesis is implanted, the bone induction structure 30 can be degraded and absorbed by the patient. Of course, in other feasible embodiments, a bone induction coating can also be directly disposed on the plurality of column units of the fixed column.

[0040] Figure 3 The cross-sectional schematic diagram of the joint replacement prosthesis according to the third embodiment of the present application is shown. The joint replacement prosthesis of the third embodiment is different from the first embodiment mainly in that the outer layer 11 of the joint replacement prosthesis of the third embodiment includes an anti-seepage platform 111 protruding from the inner layer 12 along the circumference of the inner layer 12. This can also prevent the synovial fluid from penetrating into the subchondral bone of the patient and damaging the patient's healthy bone.

[0041] Figure 4 A cross-sectional schematic diagram of a joint replacement prosthesis according to Embodiment 4 of the present application is shown. The difference between the joint replacement prosthesis of Embodiment 4 and Embodiment 1 is mainly that the fixed column 20 of the joint replacement prosthesis of Embodiment 4 also includes an anti-rotation rib 23 arranged on the outer side wall of the fixed column 20, and the anti-rotation rib 23 extends along the length direction of the fixed column 20. The provision of the anti-rotation rib 23 enables the joint replacement prosthesis to not rotate relative to the patient's bone body after implantation, thereby ensuring the stability between the joint replacement prosthesis and the patient's bone body after implantation. Specifically, there can be multiple anti-rotation ribs 23, and multiple anti-rotation ribs 23 are evenly arranged around the circumference of the fixed column 20. A porous structure can also be provided on the outer surface of the fixed column 20 between the above-mentioned anti-rotation ribs 23 to promote bone ingrowth.

[0042] Figure 5 A cross-sectional schematic diagram of a joint replacement prosthesis according to Example 5 of the present application is shown. The joint replacement prosthesis of Example 5 differs from Example 1 mainly in that a porous structure 24 is further provided on the outer surface of the fixing column 20 between the guide threads 22 of the joint replacement prosthesis of Example 5. The provision of the porous structure 24 can further promote bone fusion, thereby making the connection between the joint replacement prosthesis and the patient's bone more firmly connected.

[0043] In the present application, the target implant bone of the joint replacement prosthesis in the above embodiments is the femoral head. The outer surface of the joint replacement prosthesis contacts the patient's healthy acetabulum or artificial acetabulum, transmits loads and generates relative motion.

[0044] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0045] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0046] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A joint replacement prosthesis, characterized in that: include: Substituting a matrix (10); A fixing column (20), the fixing column (20) having a first end and a second end, the first end being connected to the displacement matrix (10), and the cross section of the fixing column (20) gradually increases from the first end to the second end; The angle a between the generatrix of the side surface of the fixing column (20) and the axis (L) of the fixing column (20) satisfies: 1°<a<5°; The replacement matrix (10) comprises an outer layer (11) and an inner layer (12) disposed between the outer layer (11) and the fixing column (20), the inner layer (12) having a porous structure, and the outer layer (11) comprising an anti-seepage platform (111) bent toward the fixing column (20) and covering the inner layer (12); or, The replacement matrix (10) comprises an outer layer (11) and an inner layer (12) arranged between the outer layer (11) and the fixing column (20), wherein the inner layer (12) has a porous structure, and the outer layer (11) comprises an anti-seepage platform (111) protruding from the inner layer (12) along the circumference of the inner layer (12).

2. The joint replacement prosthesis according to claim 1, characterized in that: The fixing column (20) is provided with a notch (21) extending from the second end to the first end, and the notch (21) divides the fixing column (20) into a plurality of column units.

3. The joint replacement prosthesis according to claim 2, characterized in that: The joint replacement prosthesis further comprises an osteoinductive structure (30) arranged at the notch (21).

4. The joint replacement prosthesis according to claim 1, characterized in that: The replacement matrix (10) has a spherical outer surface, the surface area of ​​the spherical outer surface is less than or equal to 1 / 3 of the surface area of ​​the sphere on which the spherical outer surface is located, and / or the height h of the replacement matrix (10) satisfies: h≤26 mm.

5. The joint replacement prosthesis according to claim 1, characterized in that: The replacement matrix (10) further comprises a wear-resistant coating arranged on the outer surface of the replacement matrix (10), and / or the surface roughness of the replacement matrix (10) is less than or equal to 0.1 μm.

6. The joint replacement prosthesis according to claim 1, characterized in that: The fixing column (20) is provided with a guide thread (22), or the fixing column (20) further comprises an anti-rotation rib (23) provided on the outer side wall of the fixing column (20), and the anti-rotation rib (23) extends along the length direction of the fixing column (20).

7. The joint replacement prosthesis according to any one of claims 1 to 6, characterized in that: The joint replacement prosthesis is made of metal or ceramic material.

8. The joint replacement prosthesis according to any one of claims 1 to 6, characterized in that: The replacement base (10) and the fixing column (20) are an integrally formed structure.

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