Interbody Fusion Cage

Abstract

The present invention provides an intervertebral fusion device, including an intervertebral fusion device body, the intervertebral fusion device body including: a first porous plate layer and a second porous plate layer arranged in a stacked manner; a third porous plate layer arranged between the first porous plate layer and the second porous plate layer, the third porous plate layer including a first surface and a second surface arranged oppositely, the first surface being connected to the first porous plate layer, and the second surface being connected to the second porous plate layer; wherein the intervertebral fusion device body has an initial state in a curved shape and an assembly state in a straight shape, and under preset conditions, the intervertebral fusion device body can be transformed from the assembly state to the initial state. The technical solution of the present invention effectively solves the problems of poor intervertebral fusion device support effect and poor fusion effect in the related art.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to an intervertebral fusion device. Background Art

[0002] Posterior lumbar decompression and interbody fusion is the most commonly used surgical method for the treatment of common lumbar diseases such as lumbar disc herniation and lumbar spinal stenosis. It is performed using three surgical methods: posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), and minimally invasive surgery-transforaminal lumbar interbody fusion (MIS-TLIF).

[0003] In the clinical practice of recent decades, all three surgical methods have achieved good clinical efficacy. However, the entrance and direction of the operation are still difficult points in prosthesis implantation. The best prosthesis position should be that the prosthesis is placed parallel to the coronal plane, the shape of the prosthesis is similar to the vertebral shape, and the maximum amount of bone support is achieved. However, in related technologies, intervertebral fusion is considered to be a common method for treating vertebral segment instability. The intervertebral fusion device is a titanium alloy block processed into a hollow shape, but because titanium alloy cannot grow together with bones, bone grafting is required in the hollow structure, so that the bones inside and outside the fusion device grow together, and then the titanium alloy intervertebral fusion device can be stable. Autologous iliac bone grafting has always been regarded as the "gold standard" for spinal intervertebral fusion, but autologous iliac bone grafting also has relatively more complications. In addition to pain and infection in the bone donor area, the bone graft often slips and dislocates, or collapses due to insufficient strength. Summary of the invention

[0004] The present invention aims to provide an intervertebral fusion device to solve the problems of poor supporting effect and poor fusion effect of the intervertebral fusion device in the related art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, there is provided an intervertebral fusion device, comprising an intervertebral fusion device body, the intervertebral fusion device body comprising: a first porous plate layer and a second porous plate layer stacked together; a third porous plate layer arranged between the first porous plate layer and the second porous plate layer, the third porous plate layer comprising a first surface and a second surface arranged opposite to each other, the first surface being connected to the first porous plate layer, and the second surface being connected to the second porous plate layer; wherein the intervertebral fusion device body has an initial state in a curved shape and an assembly state in a straight shape, when the intervertebral fusion device body is in the initial state, the porosity of the first porous plate layer is greater than the porosity of the third porous plate layer, the porosity of the second porous plate layer is greater than the porosity of the third porous plate layer, the thickness of the intervertebral fusion device body in the initial state is greater than its thickness in the assembly state, and under preset conditions, the intervertebral fusion device body can be transformed from the assembly state to the initial state.

[0006] Furthermore, the third porous plate layer includes a plurality of plate units, the plurality of plate units are arranged at intervals, the length direction of each plate unit is perpendicular to the length direction of the second porous plate layer, and a connecting portion connecting two adjacent plate units is arranged in the space between two adjacent plate units.

[0007] Furthermore, the connecting portion includes a strip-like structure, and each plate unit has a first end and a second end in its length direction, wherein when the intervertebral fusion device body is in a straight state, the distance between the first ends of two adjacent plate units is equal to the distance between the second ends of two adjacent plate units, and when the intervertebral fusion device body is in a curved state, the distance between two adjacent plate units gradually decreases from the first ends to the second ends of the two adjacent plate units.

[0008] Furthermore, the first porous plate layer and the second porous plate layer each include a plurality of layer units arranged at intervals, each layer unit is perpendicular to the first porous plate layer and the plate body unit, and each layer unit includes a plurality of polygonal skeletons connected to each other.

[0009] Furthermore, the plate unit includes a plurality of spatial triangular structures.

[0010] Furthermore, multiple adjacent spatial triangular structures intersect at the same point.

[0011] Furthermore, a plurality of connecting rods are arranged between the layer units, and two ends of the connecting rods are respectively connected to corresponding intersection points of corresponding polygonal structural skeletons of two adjacent layer units.

[0012] Further, the thickness of the third porous plate layer is greater than the thickness of the first porous plate layer and the thickness of the second porous plate layer, and the side wall of the third porous plate layer is provided with a mounting hole.

[0013] Further, the deformation amount of the third porous plate layer in the stacking direction is between 0.1 mm and 0.4 mm, and the deformation amount of the first porous plate layer and the second porous plate layer in the stacking direction is between 0.5 mm and 0.9 mm.

[0014] Furthermore, the first porous plate layer, the second porous plate layer and the third porous plate layer are made of TiNi memory alloy.

[0015] According to the technical solution of the present invention, the intervertebral fusion device body includes a first porous plate layer and a second porous plate layer stacked together, a third porous plate layer is arranged between the first porous plate layer and the second porous plate layer, and the first surface and the second surface of the third porous plate layer are connected to the first porous plate layer and the second porous plate layer respectively. The porosity of the first porous plate layer and the second porous plate layer is greater than that of the third porous plate layer. The compressibility of the first porous plate layer and the second porous plate layer is greater than that of the third porous plate layer. The intervertebral fusion device body can be transformed from a curved state to a straight state under a preset condition (such as after cooling), and can be transformed from a straight state to a curved state under another condition (such as after heating). When in a straight state, the first porous plate layer, the second porous plate layer and the third porous plate layer are in an initial straight state, and when in a curved state, the first porous plate layer, the second porous plate layer and the third porous plate layer are in a curved assembly state. Before implantation, the intervertebral fusion device body is in an initial state, which is curved and has a large thickness. Changing the external environment, such as cooling down, causes the intervertebral fusion device body to be transformed into an assembled state, in which it is straight and thin. After implantation, the intervertebral fusion device body returns to its initial state, in which it is curved and thick. After implantation, the intervertebral fusion device body maintains its initial state, thereby effectively supporting the bone structure, and the porous structure of the first to third porous plate layers is conducive to fusion with the bone structure. After implantation, the intervertebral fusion device body is in a curved state, reaches an ideal placement position and conforms to the curvature trend in the vertebral body, providing ideal bone support. Therefore, the technical solution of the present application effectively solves the problems of poor support effect and poor fusion effect of intervertebral fusion devices in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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:

[0017] Figure 1 A schematic side view of an embodiment of an intervertebral fusion cage according to the present invention is shown;

[0018] Figure 2 Shows Figure 1 A schematic diagram of the three-dimensional structure of the third porous plate layer;

[0019] Figure 3 Shows Figure 1 Schematic diagram of the three-dimensional structure of the intervertebral fusion cage;

[0020] Figure 4 Shows Figure 3 A cross-sectional schematic diagram of an intervertebral fusion cage;

[0021] Figure 5 Shows Figure 2 A schematic structural diagram of a third porous plate layer; and

[0022] Figure 6 Shows Figure 5 A partial cross-sectional view of the third porous plate layer.

[0023] The above drawings include the following reference numerals:

[0024] 10. First porous plate layer; 11. First surface; 12. Second surface; 20. Second porous plate layer; 21. Layer unit; 22. Connecting rod; 30. Third porous plate layer; 31. Plate body unit; 31a. First end; 31b. Second end; 32. Connecting portion; 33. Mounting hole. DETAILED DESCRIPTION

[0025] 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.

[0026] 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.

[0027] 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.

[0028] like Figure 1 As shown, in this embodiment, the intervertebral fusion device includes an intervertebral fusion device body, and the intervertebral fusion device body includes: a first porous plate layer 10, a second porous plate layer 20 and a third porous plate layer 30 which are stacked. The third porous plate layer 30 is arranged between the first porous plate layer 10 and the second porous plate layer 20, and the third porous plate layer 30 includes a first surface 11 and a second surface 12 which are arranged oppositely, the first surface 11 is connected to the first porous plate layer 10, and the second surface 12 is connected to the second porous plate layer 20; wherein, the intervertebral fusion device body has an initial state in a curved shape and an assembly state in a straight shape, and when the intervertebral fusion device body is in the initial state, the porosity of the first porous plate layer 10 is greater than the porosity of the third porous plate layer 30, the porosity of the second porous plate layer 20 is greater than the porosity of the third porous plate layer 30, and the thickness of the intervertebral fusion device body in the initial state is greater than the thickness in the assembly state, and under preset conditions, the intervertebral fusion device body can be transformed from the assembly state to the initial state.

[0029] Using the technical solution of this embodiment, the intervertebral fusion device body includes a first porous plate layer 10 and a second porous plate layer 20 which are stacked, a third porous plate layer 30 is arranged between the first porous plate layer 10 and the second porous plate layer 20, and a first surface 11 and a second surface 12 of the third porous plate layer 30 are connected to the first porous plate layer 10 and the second porous plate layer 20 respectively. The porosity of the first porous plate layer 10 and the second porous plate layer 20 is greater than that of the third porous plate layer 30. The compressibility of the first porous plate layer 10 and the second porous plate layer 20 is greater than that of the third porous plate layer 30. The intervertebral fusion device body can be transformed from a curved state to a straight state under a preset condition (such as after cooling), and can be transformed from a straight state to a curved state under another condition (such as after heating). When in a straight state, the first porous plate layer 10, the second porous plate layer 20 and the third porous plate layer 30 are in a straight initial state, and when in a curved state, the first porous plate layer 10, the second porous plate layer 20 and the third porous plate layer 30 are in a curved assembly state. Before implantation, the intervertebral fusion device body is in an initial state, which is curved and has a large thickness. Changing the external environment, such as cooling, causes the intervertebral fusion device body to be transformed into an assembly state, which is straight and has a small thickness. After implantation, the intervertebral fusion device body returns to its initial state, which is curved and has a large thickness. After implantation, the intervertebral fusion device body maintains its initial state unchanged, thereby effectively supporting the bone structure, achieving a better gap filling and internal support effect on the upper and lower spinal end plates, and the porous structure of the first to third porous plate layers is conducive to fusion with the bone structure. After implantation, in the stacking direction, the third porous plate layer 30 is compressed less, and the third porous plate layer 30 effectively plays a supporting role. The intervertebral fusion device body is in a curved state, reaches an ideal placement position and conforms to the curvature trend of the vertebral body, providing ideal bone support. Therefore, the technical solution of the present application effectively solves the problems of poor support effect and poor fusion effect of the intervertebral fusion device in the related art.

[0030] It should be noted that if Figure 1 As shown, Figure 1 The up-down direction in the figure is the thickness direction of the intervertebral fusion cage body, and the thickness direction is consistent with the stacking direction.

[0031] The porosity of the first porous plate layer 10 refers to the ratio of the pore volume of the first porous plate layer 10 to the volume of the first porous plate layer 10; the porosity of the second porous plate layer 20 refers to the ratio of the pore volume of the second porous plate layer 20 to the volume of the second porous plate layer 20; the porosity of the third porous plate layer 30 refers to the ratio of the pore volume of the third porous plate layer 30 to the volume of the third porous plate layer 30.

[0032] like Figure 2 , Figure 5 and Figure 6As shown, in this embodiment, the third porous plate layer 30 includes a plurality of plate units 31, and the plurality of plate units 31 are arranged at intervals, and the length direction L1 of each plate unit 31 is perpendicular to the length direction L2 of the second porous plate layer 20, and a connecting portion 32 connecting two adjacent plate units 31 is arranged in the space between two adjacent plate units 31. The length direction L1 of the plate unit 31 is perpendicular to the length direction L2 of the second porous plate layer, and this arrangement can prevent the third porous plate layer 30 from being compressed in the stacking direction. The plurality of plate units 31 are arranged at intervals, and the connecting portion 32 is arranged between the intervals. By adjusting the distance between the plurality of adjacent plate units 31 through the space between the adjacent plate units 31, the bending change of the third porous plate layer 30 is realized, so that the bending effect is better, and the bone structure above and below the intervertebral fusion device can be better implanted in the predetermined position and supported.

[0033] like Figure 6 As shown, in this embodiment, the connecting portion 32 includes a belt-like structure, and each plate unit 31 has a first end 31a and a second end 31b in its length direction L1, wherein when the intervertebral fusion device body is in a straight assembly state, the distance between the first ends of two adjacent plate units 31 is equal to the distance between the second ends of two adjacent plate units 31, and when the intervertebral fusion device body is in a curved initial state, the distance between two adjacent plate units 31 gradually decreases from the first end to the second end of the two adjacent plate units 31. The belt-like structure can connect adjacent plate units 31, and can better enable the third porous plate layer 30 to bend. The plate units 31 arranged at intervals enable the third porous plate layer 30 to bend while ensuring structural strength. In addition, the intervertebral fusion device is entirely manufactured by 3D printing.

[0034] like Figure 3 and Figure 4 As shown, in this embodiment, the first porous plate layer 10 and the second porous plate layer 20 each include a plurality of layer units 21 arranged at intervals, each layer unit 21 is perpendicular to the first porous plate layer 10 and the plate body unit 31, and each layer unit 21 includes a plurality of polygonal skeletons connected to each other. The polygonal skeleton is an easily deformable structure, and the layer unit 21 includes a plurality of polygonal skeletons, and the layer unit 21 is perpendicular to the first porous plate layer 10 and the plate body unit 31. This arrangement makes the layer unit 21 easier to deform in a direction perpendicular to the first porous plate layer 10, thereby being better adapted to the bone structure and better integrated with the bone structure. Two adjacent polygonal skeletons have a common edge, and this arrangement increases the connection tightness of the layer unit 21. This makes the layer unit 21 less likely to disperse and be damaged. In this embodiment, the polygonal skeleton is a hexagonal structure.

[0035] In an embodiment not shown in the figure, the layer unit may also include a circular structure or a quadrilateral structure, a pentagonal structure, etc. The effects are similar to those described above and will not be repeated here.

[0036] like Figure 4 As shown, in this embodiment, the plate unit 31 includes a plurality of spatial triangular structures. The triangular structure is stable and not easily deformed.

[0037] like Figure 4 As shown, in this embodiment, multiple adjacent spatial triangular structures intersect at the same point. The above-mentioned spatial triangular structure means that multiple triangles share the same vertex, and thus the spatial triangles are arranged divergently. This makes the structure of the plate unit 31 more stable and the deformation less.

[0038] like Figure 3 and Figure 4 As shown, in this embodiment, a plurality of connecting rods 22 are arranged between the layer units 21, and the two ends of the connecting rod 22 are respectively connected to the corresponding intersections of the corresponding polygonal structural skeletons of two adjacent layer units 21. The connecting rod 22 connects two adjacent layer units 21, and the connecting rod 22 is perpendicular to the layer units 21, and the corresponding intersections of the corresponding polygonal structural skeletons in the plurality of layer units 21 are kept on the same straight line. This arrangement enables the connection of the plurality of layer units 21 to be completed by only one connecting rod 22, which is simple and efficient.

[0039] In an embodiment not shown in the figure, the layer units are arranged in a staggered manner, and in this case, the connecting rod can also be bent or curved to connect multiple layer units.

[0040] like Figure 1 and Figure 5 As shown, in this embodiment, the thickness of the third porous plate layer 30 is greater than the thickness of the first porous plate layer 10 and the thickness of the second porous plate layer 20. The side wall of the third porous plate layer 30 is provided with a mounting hole 33. The thickness of the third porous plate layer 30 is relatively large, so that its structure is more stable and basically does not change, thereby maintaining the overall rigidity and strength of the intervertebral fusion device. When subjected to pressure, the first porous plate layer 10 and the second porous plate layer 20 can be deformed to adapt to the shape of the bone structure, thereby achieving a better support effect. In this embodiment, the thickness ratio of the first porous plate layer 10, the second porous plate layer 20, and the third porous plate layer 30 is 1:1:2.

[0041] In an embodiment not shown in the drawings, the thickness ratio of the first porous plate layer, the second porous plate layer, and the third porous plate layer is 1:1:1.

[0042] The deformation amount of the third porous plate layer 30 in the stacking direction is between 0.1 mm and 0.4 mm, and the deformation amount of the first porous plate layer 10 and the second porous plate layer 20 in the stacking direction is between 0.5 mm and 0.9 mm.

[0043] like Figure 1 and Figure 3 As shown, in this embodiment, the thickness of the intervertebral fusion device body is 10 mm, the deformation amount of the third porous plate layer 30 in the stacking direction is 0.2 mm, and the deformation amount of the first porous plate layer 10 and the second porous plate layer 20 in the stacking direction is 0.8 mm. At this time, the deformation effect can better adapt to the shape of the bone structure, thereby ensuring the support effect of the intervertebral fusion device.

[0044] like Figure 1 As shown, in this embodiment, the material of the first porous plate layer 10, the second porous plate layer 20 and the third porous plate layer 30 is a memory alloy. The memory alloy has a large bending capacity, high plasticity and superelasticity. And the shape can change with the change of temperature. After the intervertebral fusion device is implanted, the memory alloy can maintain a fixed shape, thereby achieving a better support effect.

[0045] The amount of deformation recovery is related to two factors: 1) the deformation of the memory alloy itself, and 2) whether the structural design can easily provide obstacles to the deformation of the memory alloy. For example, the triangular support structure is not easy to exert the deformation capacity of the memory alloy, but the parallelogram and regular hexagonal structures are relatively easy. This embodiment fully analyzes the characteristics of both. The present invention expects that the deformation of the upper and lower layers is larger, so that the height of the intervertebral fusion device can be low before and during implantation, and the intervertebral fusion device can restore the designed height after implantation. The height increase can achieve better gap filling and internal support effects on the upper and lower spinal end plates. It uses its own height to open the narrow intervertebral space, so that the tension of the loose fiber ring, ligaments, joint capsules and other soft tissues can be restored. At the same time, a good pore structure is obtained while restoring, which is convenient for bone cell growth, because bone cells have a growth orientation for holes of a certain size. In other words, a pore structure of a certain size is easy to lead to bone growth, that is, bone integration. However, the third porous plate layer 30 is not expected to deform too much. The human spine is a stress-bearing environment, and the relatively strong anti-deformation ability of the third porous plate layer 30 can actually ensure the minimum thickness of the implant without causing the implant to be compressed due to uncontrollable strength and stiffness.

[0046] Preferably, the intervertebral fusion device body of the present embodiment is made of TINI memory alloy (nickel-titanium memory alloy) by 3D printing technology. TINI memory alloy (nickel-titanium memory alloy) can automatically restore its own plastic deformation to its original shape at a certain temperature. The initial state of the intervertebral fusion device of the present embodiment is curved, and the plastic deformation is a straight assembly state with reduced thickness under low temperature conditions. After implantation in the patient's body, when the temperature rises to a preset temperature, the first porous plate layer 10, the second porous plate layer 20 and the third porous plate layer 30 can be restored to the initial state (become curved and increase in thickness) under the memory capacity of TINI memory alloy (nickel-titanium memory alloy), so that it is close to the ideal shape and provides sufficient bone support. During implantation, the intervertebral fusion device body enters between the two vertebrae with a smaller thickness, and expands after implantation to better fit the surfaces of the upper and lower vertebrae.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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 intervertebral fusion cage, characterized in that: The invention comprises an intervertebral fusion device body, wherein the intervertebral fusion device body comprises: A first porous plate layer (10) and a second porous plate layer (20) arranged in a stacked manner; a third porous plate layer (30) disposed between the first porous plate layer (10) and the second porous plate layer (20), the third porous plate layer (30) comprising a first surface (11) and a second surface (12) disposed opposite to each other, the first surface (11) being connected to the first porous plate layer (10), and the second surface (12) being connected to the second porous plate layer (20); The intervertebral fusion device body has a curved initial state and a straight assembly state; when the intervertebral fusion device body is in the initial state, the porosity of the first porous plate layer (10) is greater than the porosity of the third porous plate layer (30); the porosity of the second porous plate layer (20) is greater than the porosity of the third porous plate layer (30); the thickness of the intervertebral fusion device body in the initial state is greater than its thickness in the assembly state; and under preset conditions, the intervertebral fusion device body can be transformed from the assembly state to the initial state; The third porous plate layer (30) comprises a plurality of plate units (31), the plurality of plate units (31) being arranged at intervals, the length direction (L1) of each plate unit (31) being perpendicular to the length direction (L2) of the second porous plate layer (20), and a connection portion (32) connecting the two adjacent plate units (31) being provided in the space between two adjacent plate units (31); The connecting portion (32) comprises a belt-like structure, and each of the plate units (31) has a first end (31a) and a second end (31b) in the length direction (L1) thereof, wherein when the intervertebral fusion device body is in the straight state, the distance between the first ends of two adjacent plate units (31) is equal to the distance between the second ends of two adjacent plate units (31), and when the intervertebral fusion device body is in the curved state, the distance between two adjacent plate units (31) gradually decreases from the first ends to the second ends of the two adjacent plate units (31); The first porous plate layer (10) and the second porous plate layer (20) each comprise a plurality of layer units (21) arranged at intervals, each of the layer units (21) being perpendicular to the first porous plate layer (10) and the plate body unit (31), and each of the layer units (21) comprising a plurality of polygonal skeletons connected to each other; The thickness of the third porous plate layer (30) is greater than the thickness of the first porous plate layer (10) and the thickness of the second porous plate layer (20), and a mounting hole (33) is provided on a side wall of the third porous plate layer (30).

2. The intervertebral fusion cage according to claim 1, characterized in that: The plate unit (31) comprises a plurality of spatial triangular structures.

3. The intervertebral fusion cage according to claim 2, characterized in that: A plurality of adjacent spatial triangular structures intersect at the same point.

4. The intervertebral fusion cage according to claim 1, characterized in that: A plurality of connecting rods (22) are arranged between the layer units (21), and two ends of the connecting rods (22) are respectively connected to corresponding intersection points of corresponding polygonal skeletons of two adjacent layer units (21).

5. The intervertebral fusion cage according to claim 1, characterized in that: The deformation amount of the third porous plate layer (30) in the stacking direction is between 0.1 mm and 0.4 mm, and the deformation amount of the first porous plate layer (10) and the second porous plate layer (20) in the stacking direction is between 0.5 mm and 0.9 mm.

6. The intervertebral fusion cage according to claim 1, characterized in that: The material of the first porous plate layer (10), the second porous plate layer (20) and the third porous plate layer (30) is TiNi memory alloy.

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