Axis prosthesis

Abstract

The present invention provides an axis prosthesis, comprising: a first support assembly, one end of the first support assembly is connected to the atlas, and the other end of the first support assembly is used to connect to the third cervical vertebra; a second support assembly, one end of the second support assembly is used to connect to the atlas, and the other end of the second support assembly is used to connect to the third cervical vertebra; wherein the first support assembly is connected to the second support assembly to jointly support the atlas. The axis prosthesis of the present invention solves the problem of weak fixation of the axis prosthesis in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of prostheses, and in particular to an axis prosthesis. Background Art

[0002] The axis, the second cervical vertebra, is the strongest vertebra in the cervical spine. It forms the atlantoaxial joint with the atlas and controls the rotation of the head. It is an important part of the spine. Bone defects in the axis are usually caused by trauma, infection, tumors, etc. Surgical resection is one of the effective treatments, and the selection of suitable prosthetic implants is one of the current difficulties in the field of orthopedics.

[0003] The traditional prosthesis for replacing the axis is a titanium mesh, and its implantation effect is often not ideal. On the one hand, the contact area between the titanium mesh and the vertebral body is small, and long-term implantation has a greater risk of collapse; on the other hand, due to the special anatomical structure of the axis, the titanium mesh structure does not conform to the anatomical structure of the axis and cannot be stably implanted, which may cause prosthesis dislocation.

[0004] In recent years, with the development of 3D printing technology, metal 3D printed axis prosthesis has become a good choice to replace axis resection. 3D printing technology can produce prostheses that conform to the anatomical structure of the axis, which has good stability compared to titanium mesh; in addition, the 3D printed porous structure is in contact with the vertebral end plate, which will form bone ingrowth after surgery, reduce the chance of collapse, and the prosthesis will also form good biological fixation. Summary of the invention

[0005] The main purpose of the present invention is to provide an axis prosthesis to solve the problem of weak fixation of the axis prosthesis in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, there is provided an axis prosthesis, comprising: a first support assembly, one end of the first support assembly is used to connect to the atlas, and the other end of the first support assembly is used to connect to the third cervical vertebra; a second support assembly, one end of the second support assembly is used to connect to the atlas, and the other end of the second support assembly is used to connect to the third cervical vertebra; wherein the first support assembly is connected to the second support assembly to jointly support the atlas.

[0007] Furthermore, the axis vertebra prosthesis further comprises: a connecting assembly, and the first supporting assembly is connected to the second supporting assembly via the connecting assembly.

[0008] Furthermore, a first connecting hole is provided on the first supporting component, and the connecting component includes: a nail button, which is arranged on the second supporting component; and a connecting screw, which passes through the first connecting hole and is connected to the nail button to connect the first supporting component and the second supporting component.

[0009] Furthermore, the second support assembly includes a first support body and a second support body, and there are two nail buckles and connecting screws, and the two nail buckles are respectively arranged on the first support body and the second support body; two first connecting holes are provided on the first support assembly, and the two first connecting holes are arranged one-to-one with the two nail buckles, so that the connecting screws pass through the first connecting holes and are connected to the corresponding nail buckles; wherein, the first support body and the second support body are respectively connected to the atlas and the third cervical vertebra.

[0010] Furthermore, the nail button is made of polyethylene material.

[0011] Furthermore, the first support component is provided with a first connection part and a second connection part, and the first support component is fitted with the lower articular surface of the atlas through the first connection part, and the first support component is fitted with the end plate of the third cervical vertebra close to the axis side through the second connection part.

[0012] Furthermore, a first positioning portion and a second positioning portion are provided on the first support assembly, and the first support assembly is fixed to the atlas through the first positioning portion, and is fixed to the third cervical vertebra through the second positioning portion.

[0013] Furthermore, a third connection part and a fourth connection part are provided on the second support component. The second support component is fitted with the lower articular surface of the atlas through the third connection part, and the second support component is fitted with the articular process of the third cervical vertebra close to the axis through the fourth connection part.

[0014] Furthermore, a third positioning portion and a fourth positioning portion are provided on the second support assembly, the second support assembly is positioned on the atlas through the third positioning portion, and the second support assembly is fixed on the third cervical vertebra through the fourth positioning portion.

[0015] Furthermore, the third positioning portion includes a positioning baffle, and the fourth positioning portion includes a fixing plate, which is provided with a positioning hole so that the second support assembly is connected to the third cervical vertebra by connecting screws passing through the positioning hole and connected to the third cervical vertebra.

[0016] Furthermore, the first supporting component is provided with a bone grafting cavity for filling with bones.

[0017] Furthermore, a plurality of through holes are provided on the first supporting component so that blood can flow through the first supporting component through the through holes.

[0018] The axis prosthesis using the technical solution of the present invention is provided with two groups of support components, a first support component and a second support component. The two groups of support components are connected to each other and are respectively connected to the atlas and the third cervical vertebra to jointly support the atlas. In addition, the two groups of support components are connected to form a stable structure, which solves the problem of loose fixation of the axis prosthesis in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 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:

[0020] Figure 1 A schematic structural diagram of an embodiment of an axis prosthesis according to the present invention is shown;

[0021] Figure 2 A front view showing an embodiment of the present invention in which the axis prosthesis is connected to the atlas and the third cervical vertebra;

[0022] Figure 3 A side view showing an embodiment of the present invention in which the axis prosthesis is connected to the atlas and the third cervical vertebra;

[0023] Figure 4 A front view of an embodiment of a first support assembly in an axis prosthesis of the present invention is shown;

[0024] Figure 5 A side view showing an embodiment of a first support assembly in an axis prosthesis of the present invention;

[0025] Figure 6 A schematic diagram showing an embodiment of a second supporting component in an axis vertebral prosthesis of the present invention.

[0026] The above drawings include the following reference numerals:

[0027] 10. First supporting assembly; 11. First connecting hole; 12. First connecting part; 13. Second connecting part; 14. First positioning part; 15. Second positioning part; 16. Through hole; 20. Second supporting assembly; 21. First supporting body; 22. Second supporting body; 23. Third connecting part; 24. Fourth connecting part; 25. Third positioning part; 26. Fourth positioning part; 30. Connecting assembly; 31. Button; 40. Atlas; 50. Third cervical vertebra. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] The present invention provides an axis prosthesis, please refer to Figures 1 to 6 The axis prosthesis includes: a first support component 10, one end of the first support component 10 is connected to the atlas 40, and the other end of the first support component 10 is used to connect to the third cervical vertebra 50; a second support component 20, one end of the second support component 20 is used to connect to the atlas 40, and the other end of the second support component 20 is used to connect to the third cervical vertebra 50; wherein the first support component 10 is connected to the second support component 20 to jointly support the atlas 40.

[0030] The axis prosthesis of the present invention is provided with two groups of support components, a first support component 10 and a second support component 20. The two groups of support components are connected to each other and are respectively connected to the atlas and the third cervical vertebra to jointly support the atlas. In addition, the two groups of support components are connected to form a stable structure, which solves the problem of loose fixation of the axis prosthesis in the prior art.

[0031] The axis prosthesis further includes a connecting assembly 30 , through which the first supporting assembly 10 is connected to the second supporting assembly 20 .

[0032] Preferably, the first support assembly and the second support assembly in the present application form a stable truss structure through a connecting assembly.

[0033] The first supporting assembly 10 is provided with a first connecting hole 11, and the connecting assembly 30 includes: a nail button 31, which is arranged on the second supporting assembly 20; and a connecting screw, which passes through the first connecting hole 11 and is connected to the nail button 31 to connect the first supporting assembly 10 and the second supporting assembly 20.

[0034] The second support assembly 20 includes a first support body 21 and a second support body 22, and there are two nail buttons 31 and connecting screws, and the two nail buttons 31 are respectively arranged on the first support body 21 and the second support body 22; the first support assembly 10 is provided with two first connecting holes 11, and the two first connecting holes 11 are arranged one-to-one with the two nail buttons 31, so that the connecting screws pass through the first connecting holes 11 and are connected to the corresponding nail buttons 31; wherein, the first support body 21 and the second support body 22 are respectively connected to the atlas 40 and the third cervical vertebra 50.

[0035] like Figure 6 As shown, the second support assembly in this embodiment includes two left and right support bodies, each support body is provided with a mounting hole for installing a nail button, two nail buttons are respectively arranged in the mounting holes and fixed in the mounting holes by a limiting structure. In addition, a threaded hole is provided in the middle of the nail button, and two first connecting holes are provided at corresponding positions on the first support assembly. The connecting screw passes through the first connecting hole and is connected with the corresponding threaded hole on the nail button to fix the first support assembly and the second support assembly.

[0036] Preferably, the nail button 31 is made of polyethylene material.

[0037] The first support component 10 is provided with a first connecting portion 12 and a second connecting portion 13. The first support component 10 is fitted to the lower articular surface of the atlas 40 through the first connecting portion 12, and the first support component 10 is fitted to the end plate of the third cervical vertebra 50 close to the axis side through the second connecting portion 13.

[0038] The first connecting portion 12 is the upper connecting surface of the axis, and the upper connecting surface is configured to correspond to the shape of the lower articular surface of the atlas so as to fit closely with the lower articular surface. A positioning protrusion is provided on the first connecting portion 12 to locate the positional relationship between the first supporting component and the atlas.

[0039] The first support assembly 10 is provided with a first positioning portion 14 and a second positioning portion 15 . The first support assembly 10 is fixed to the atlas 40 via the first positioning portion 14 , and is fixed to the third cervical vertebra 50 via the second positioning portion 15 .

[0040] The first positioning portion 14 and the second positioning portion 15 are connecting holes, and connecting screws pass through the connecting holes to fix the first supporting assembly on the atlas.

[0041] The second support assembly 20 is provided with a third connection portion 23 and a fourth connection portion 24. The second support assembly 20 is fitted with the lower articular surface of the atlas 40 through the third connection portion 23, and the second support assembly 20 is fitted with the articular process of the third cervical vertebra 50 close to the axis side through the fourth connection portion 24. The second support assembly 20 is provided with a third positioning portion 25 and a fourth positioning portion 26. The second support assembly 20 is positioned on the atlas 40 through the third positioning portion 25, and the second support assembly 20 is fixed to the third cervical vertebra 50 through the fourth positioning portion 26. The third positioning portion 25 includes a positioning baffle, and the fourth positioning portion 26 includes a fixing plate, and the fixing plate is provided with a positioning hole, so that the second support assembly 20 is connected to the third cervical vertebra 50 by connecting screws passing through the positioning holes and the third cervical vertebra 50.

[0042] The third connecting part 23 and the fourth connecting part 24 in this embodiment are connecting holes, and connecting screws pass through the connecting holes to fix the second support assembly on the atlas and the third cervical vertebra. At the same time, in order to limit the positional relationship between the second support assembly and the atlas and the third cervical vertebra, a positioning baffle and a fixing plate are also provided to facilitate the installation and connection of the second support assembly with the atlas and the third cervical vertebra.

[0043] The first supporting component 10 is provided with a bone grafting cavity for filling with bones.

[0044] In this embodiment, a bone grafting cavity is further provided on the first supporting component 10. The bone grafting cavity is arranged in the middle of the first supporting component and has an opening at one end so as to fill the bone fragments into the bone grafting cavity.

[0045] The first support component 10 is provided with a plurality of through holes 16 so that blood can flow through the first support component 10 through the through holes.

[0046] The plurality of through holes 16 can connect the two sides of the first supporting component so that blood circulation is not hindered.

[0047] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0048] The present invention designs an anterior-posterior combined fixed axis prosthesis, which is manufactured by 3D printing, and its design concept is different from the original scheme. The present invention not only designs a prosthesis in the anterior route, but also designs a prosthesis in the posterior route, and fixes the anterior and posterior routes together through a special connection method, so that the prosthesis is placed more stably.

[0049] The present invention is a front-back combined fixed axis prosthesis, which is composed of an anterior first support assembly, a posterior left first support body and a right second support body. The upper and lower joint surfaces of the entire axis prosthesis are designed with anatomical surface structures, which can achieve complete matching with the bone contact surface, and the first and second support assemblies adopt a porous structure similar to trabecular bone to achieve bone ingrowth after the prosthesis is implanted; the upper joint surface of the first support assembly of the anterior road fits with the lower articular surface of the atlas, and the lower joint surface fits with the upper end plate of the third cervical vertebra, and two screws are driven in the upper and lower parts to increase the initial stability of implantation; the upper joint surface of the second support assembly of the posterior road fits with the lower articular surface of the atlas, and the lower joint surface fits with the upper articular process of the third cervical vertebra, and the fixing plate below the prosthesis is provided with screw holes, and the screws are driven into the pedicle of the third cervical vertebra. A bone grafting hole is left in the middle of the first support assembly, and the inner wall of the bone grafting hole is a porous structure similar to trabecular bone, which can be used for bone grafting fusion to achieve better long-term stability.

[0050] The baffle on the first anterior support component plays a stabilizing role during postoperative placement to prevent the prosthesis from moving before screwing; the four screws that fix the anterior prosthesis use a zero-trace method to reduce the possibility of postoperative dysphagia in patients. The connection hole on the prosthesis is an M3 threaded hole for prosthesis clamping; the blood supply hole is a through hole 16, which facilitates blood circulation inside and outside the prosthesis and accelerates bone graft fusion.

[0051] Two screw holes are set in the first anterior support component, and a polyethylene nail buckle is placed in the second posterior support component. The screw passes through the anterior prosthesis and is driven into the polyethylene nail buckle. The nail buckle "bites" the screw to achieve joint fixation of the anterior and posterior prostheses, combining into a "truss" structure, which is more stable as a whole. At the same time, after the screw is driven in, it can also prevent the upward screw of the first anterior support component from falling out.

[0052] The axis prosthesis of the present invention has the following characteristics:

[0053] 1. The connection mode between the upper and lower contact surfaces of the prosthesis and the adjacent vertebral bodies and the bone interface of the trabecular structure.

[0054] 2. The first support assembly, the second support assembly and the connecting assembly are all manufactured using 3D printing technology and are integrally formed.

[0055] 3. The upper and lower endplate layers are designed using anatomical cross-sections scanned by CT data.

[0056] 4. The contact surface of the prosthesis is a porous structure, which increases the long-term stability of the posterior approach. The anterior and posterior prostheses are fastened and connected by screws and staples to achieve overall joint fixation and a more stable structure.

[0057] 5. The screws of the combined anterior and posterior prostheses can also prevent the screws driven upward into the first anterior support component from falling out.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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. An axis prosthesis, characterized in that: include: A first support component (10), one end of the first support component (10) being used to connect to the atlas (40), and the other end of the first support component (10) being used to connect to the third cervical vertebra (50); a second support assembly (20), one end of the second support assembly (20) being used for connecting to the atlas (40), and the other end of the second support assembly (20) being used for connecting to the third cervical vertebra (50); Wherein, the first support assembly (10) is connected to the second support assembly (20) to jointly support the atlas (40); The axis prosthesis further comprises: a connection assembly (30), wherein the first support assembly (10) is connected to the second support assembly (20) via the connection assembly (30); The first supporting component (10) is provided with a first connecting hole (11), and the connecting component (30) comprises: a nail button (31), the nail button (31) is arranged on the second supporting component (20); and a connecting screw, the connecting screw passes through the first connecting hole (11) and is connected to the nail button (31), so as to connect the first supporting component (10) and the second supporting component (20); The second support assembly (20) comprises two left and right support bodies, namely a first support body (21) and a second support body (22), the number of the nail buckles (31) and the number of the connecting screws are both two, and the two nail buckles (31) are respectively arranged on the first support body (21) and the second support body (22); the first support assembly (10) is provided with two first connecting holes (11), and the two first connecting holes (11) and the two nail buckles (31) are arranged one-to-one correspondingly, so that the connecting screw passes through the first connecting holes (11) and is connected to the corresponding nail buckles (31); wherein the first support body (21) and the second support body (22) are respectively connected to the atlas (40) and the third cervical vertebra (50).

2. The axis prosthesis according to claim 1, characterized in that: The nail button (31) is made of polyethylene material.

3. The axis prosthesis according to claim 1, characterized in that: The first support component (10) is provided with a first connecting portion (12) and a second connecting portion (13); the first support component (10) is in contact with the lower articular surface of the atlas (40) via the first connecting portion (12); and the first support component (10) is in contact with the end plate of the third cervical vertebra (50) close to the axis side via the second connecting portion (13).

4. The axis prosthesis according to claim 1, characterized in that: The first support component (10) is provided with a first positioning portion (14) and a second positioning portion (15); the first support component (10) is fixed to the atlas (40) via the first positioning portion (14), and is fixed to the third cervical vertebra (50) via the second positioning portion (15).

5. The axis prosthesis according to claim 1, characterized in that: The second support component (20) is provided with a third connecting portion (23) and a fourth connecting portion (24); the second support component (20) is in contact with the lower articular surface of the atlas (40) via the third connecting portion (23); and the second support component (20) is in contact with the articular process of the third cervical vertebra (50) close to the axis side via the fourth connecting portion (24).

6. The axis prosthesis according to claim 1, characterized in that: The second support assembly (20) is provided with a third positioning portion (25) and a fourth positioning portion (26); the second support assembly (20) is positioned on the atlas (40) via the third positioning portion (25); and the second support assembly (20) is fixed on the third cervical vertebra (50) via the fourth positioning portion (26).

7. The axis prosthesis according to claim 6, characterized in that: The third positioning portion (25) comprises a positioning baffle, and the fourth positioning portion (26) comprises a fixing plate, wherein the fixing plate is provided with a positioning hole so as to connect the second supporting assembly (20) with the third cervical vertebra (50) by means of connecting screws passing through the positioning hole and connecting with the third cervical vertebra (50).

8. The axis prosthesis according to claim 1, characterized in that: The first supporting component (10) is provided with a bone grafting cavity for filling with bones.

9. The axis prosthesis according to claim 1, characterized in that: The first support component (10) is provided with a plurality of through holes (16) so that blood can flow through the first support component (10) through the through holes.

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