A spinal cage

Abstract

This invention provides a spinal fusion device, belonging to the technical field of spinal fusion devices, comprising: support blocks, with a support space formed between two support blocks; a first force-bearing structure located in the support space, the first force-bearing structure including a first force-bearing member, the two support blocks being connected through the first force-bearing member; and a second force-bearing structure including two second force-bearing members, both of which are located in the support space and respectively connected to the two support blocks. This invention employs a dual-stage force-bearing structure design. In the initial compression stage, only the first force-bearing member provides elastic support, and the relatively small elastic modulus provides a certain amount of strain, promoting osseointegration. When the compression displacement increases to the point where the second force-bearing members contact, the dual structures work together to bear the load, significantly improving the overall compressive strength and stability. The three-period minimal curved surface has an extremely high specific surface area, which is conducive to cell attachment, proliferation, and differentiation, and the zero average curvature avoids stress concentration.

Description

Technical Field

[0001] This invention belongs to the field of spinal fusion device technology and relates to a spinal fusion device. Background Technology

[0002] Traditional spinal fusion surgery achieves intervertebral bony fusion by implanting rigid fusion devices (such as PEEK or titanium alloy fusion devices). Although it can stabilize spinal segments in the short term, its static mechanical properties have significant limitations. Rigid support leads to excessive load concentration at the fusion device-bone interface, causing stress shielding effect, inhibiting surrounding bone remodeling, and increasing the risk of fusion failure and adjacent segment degeneration. In addition, completely restricting segmental micromovement may affect the transmission of physiological loads in the spine, affect the bone biological environment, and lead to pseudoarthrosis.

[0003] In summary, the existing PEEK fusion device is bioinert and may lead to poor osseointegration, while the titanium alloy fusion device has a large elastic modulus and is prone to stress shielding, which may cause degeneration of adjacent vertebrae in the long term, indicating that there is considerable room for improvement. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned problems in the prior art by proposing a spinal fusion device.

[0005] The objective of this invention can be achieved through the following technical solution: a spinal fusion device, comprising:

[0006] There are two support blocks, and a support space is formed between the two support blocks;

[0007] A first force-bearing structure is located in the support space. The first force-bearing structure includes a first force-bearing component, and the two support blocks are connected through the first force-bearing component.

[0008] The second force-bearing structure includes two second force-bearing components, both of which are located in the support space and are respectively connected to the two support blocks, and a contact gap is formed between the two second force-bearing components.

[0009] When the two support blocks are compressed and the two second force-bearing members separate, the first force-bearing member applies force to the two support blocks; when the two support blocks are compressed and the two second force-bearing members are in contact, the first force-bearing member and the second force-bearing member apply force to the two support blocks simultaneously.

[0010] In the aforementioned spinal fusion device, the second force-bearing component is provided with a first support surface and a second support surface on both sides, and the first support surface and the second support surface are smoothly connected.

[0011] In the aforementioned spinal fusion device, the first support surface includes at least two first unit cell planes, the first unit cell planes are wavy, and a first connecting groove is provided between two adjacent first unit cell planes. The second support surface includes at least two second unit cell planes, the second unit cell planes are wavy, and a second connecting groove is provided between two adjacent second unit cell planes. When the first support surface and the second support surface coincide, the first connecting groove and the second connecting groove are connected.

[0012] In the aforementioned spinal fusion device, the projection of the first unit cell plane in the first connecting groove onto the protruding portion of the first support surface is provided with a first connecting hole, and the projection of the second unit cell plane in the second connecting groove onto the protruding portion of the second support surface is provided with a second connecting hole, and the first connecting hole and the second connecting hole are connected.

[0013] In one of the spinal fusion devices described above, the projection of the midline of the first unit cell plane onto the first support surface coincides with the projection of the midline of the second unit cell plane onto the second support surface. The projections of the first unit cell plane onto the first support surface and the second unit cell plane onto the second support surface are symmetrical along their midlines, thereby causing the first connecting hole and the second connecting hole to be offset.

[0014] In the aforementioned spinal fusion device, a first connecting portion is formed between two adjacent first connecting holes in the same first connecting groove, and each of the first connecting portions is connected in sequence. A second connecting portion is formed between two adjacent second connecting holes in the same second connecting groove, and each of the second connecting portions is connected in sequence. The first connecting portion and the second connecting portion are integral.

[0015] In one of the aforementioned spinal fusion devices, the second force-bearing component is a one-piece molded component.

[0016] In the aforementioned spinal fusion device, the first force-bearing component includes two inclined portions and one vertical portion. One end of each of the two inclined portions is connected to one of the two support blocks, and the other end of each of the two inclined portions is connected to both ends of the vertical portion. The two inclined portions are inclined to the two support blocks respectively, and the vertical portion is perpendicular to the support blocks.

[0017] In the aforementioned spinal fusion device, the number of the first force-bearing components is at least two, and each of the first force-bearing components is distributed around the center of the second force-bearing structure. The inclined portion gradually approaches the second force-bearing structure from the end connected to the support block to the end connected to the vertical portion.

[0018] In the aforementioned spinal fusion device, the support block is provided with a first bone graft window, the second force-bearing member extends toward and is located at the first bone graft window, and the second force-bearing member is provided with a second bone graft window.

[0019] Compared with the prior art, the beneficial effects of this invention are as follows: This invention adopts a dual-level force-bearing structure design, realizing a graded load-bearing and progressive support mechanism; in the initial compression stage, only the first force-bearing component provides elastic support, and the small elastic modulus provides a certain strain, which can promote osseointegration; when the compression displacement increases to the point where the second force-bearing component contacts, the dual structure works together to bear the load, significantly improving the overall compressive strength and stability; it takes into account both the osseointegration strain stimulation and the structural reliability under long-term load, which helps to promote stress adaptation during the osseointegration process; the first support surface and the second support surface are smoothly connected, and the stress is evenly distributed through the curved surface distribution, enhancing the initial stability, while reducing the risk of postoperative adjacent segment degeneration, effectively avoiding the soft tissue damage and vertebral edge stress concentration problems that may be caused by the sharp-edged structure of traditional fusion devices, improving patient comfort and safety; by setting connecting holes in the protruding part of the unit cell plane and realizing the connection between the upper and lower connecting holes, a vertical bone ingrowth channel network is constructed; The structure not only enhances the penetrating growth capacity of internal bone tissue but also increases the bone filling rate within the fusion cage, promoting the integration of internal and external bone and significantly improving fusion efficiency and biomechanical stability. The symmetrical but staggered interconnecting hole layout ensures connectivity between the upper and lower channels while forming an interlaced support framework structure. This maintains sufficient structural strength while avoiding "weak zones" caused by channel alignment, optimizing stress distribution and improving the overall structure's compressive and fatigue resistance, while still preserving a good bone ingrowth path. The inclined section design avoids stress concentration caused by right-angle connections between the support block and the vertical section, allowing the load to be gradually transferred to the vertical section via an inclined path, significantly reducing local stress peaks and improving the structure's fatigue resistance and long-term durability. The vertical section provides sufficient compressive stiffness to maintain intervertebral disc height, while the inclined section allows for minor elastic deformation, enabling the fusion cage to better adapt to the physiological micro-movements of the spine after implantation, reducing stress shielding effects and promoting bone growth and fusion progress. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the spinal fusion device of the present invention.

[0021] Figure 2 This is an exploded view of the spinal fusion device of the present invention.

[0022] Figure 3 This is a schematic diagram of the structure of the second force-bearing component of the present invention.

[0023] Figure 4This is a top view of the second force-bearing component of the present invention.

[0024] Figure 5 for Figure 4 A cross-sectional view from the perspective of AA.

[0025] Figure 6 This is a front view of the second force-bearing component of the present invention.

[0026] Figure 7 for Figure 6 A cross-sectional view from the perspective of a BB (Black and White) camera.

[0027] Figure 8 This is a bottom view of the second force-bearing component of the present invention.

[0028] In the figure, 100 is the support block; 110 is the first bone graft window; 200 is the first load-bearing component; 210 is the inclined part; 220 is the vertical part; 300 is the second load-bearing component; 301 is the second bone graft window; 310 is the first support surface; 311 is the first unit cell plane; 312 is the first connecting groove; 313 is the first connecting hole; 314 is the first connecting part; 320 is the second support surface; 321 is the second unit cell plane; 322 is the second connecting groove; 323 is the second connecting hole; and 324 is the second connecting part. Detailed Implementation

[0029] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0030] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0031] Furthermore, in this invention, descriptions involving terms such as "first," "second," and "a" are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0034] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0035] like Figures 1-8 As shown, a spinal fusion device includes: a support block 100, a first force-bearing structure, and a second force-bearing structure.

[0036] There are two support blocks 100, and a support space is formed between the two support blocks 100.

[0037] The first force-bearing structure is located in the support space, and the first force-bearing structure includes a first force-bearing component 200. The two support blocks 100 are connected through the first force-bearing component 200.

[0038] The second force-bearing structure includes two second force-bearing components 300, both of which are located in the support space and are respectively connected to the two support blocks 100, and a contact gap is formed between the two second force-bearing components 300.

[0039] Specifically, when the two support blocks 100 are compressed and the two second force-bearing members 300 are separated, the first force-bearing member 200 applies force to the two support blocks 100; when the two support blocks 100 are compressed and the two second force-bearing members 300 are in contact, the first force-bearing member 200 and the second force-bearing member 300 simultaneously apply force to the two support blocks 100.

[0040] In this embodiment, the present invention adopts a dual-stage load-bearing structure design, realizing a graded load-bearing and progressive support mechanism. In the initial compression stage, only the first load-bearing component 200 provides elastic support, and the small elastic modulus provides a certain strain, which can promote osseointegration. When the compression displacement increases to the point where the second load-bearing component 300 contacts, the dual structure works together to bear the load, significantly improving the overall compressive strength and stability. It takes into account both the osseointegration strain stimulation and the structural reliability under long-term load, which helps to promote stress adaptation during the osseointegration process.

[0041] It is worth noting that the spinal fusion device adopts a dual-rigidity design: the first stage is low-rigidity, which generates about 5% strain stimulation when subjected to about 1 / 2 of body weight, promoting bone growth; the second stage is high-rigidity, where the double support plates overlap under extreme load (about 3 times body weight), providing strong support to maintain stability.

[0042] like Figures 1-8 As shown, based on the above embodiment, the second force-bearing member 300 is provided with a first support surface 310 and a second support surface 320 on both sides, and the first support surface 310 and the second support surface 320 are smoothly connected.

[0043] In this embodiment, the first support surface 310 and the second support surface 320 are smoothly connected, which distributes the stress evenly through the curved surface distribution, enhances the initial stability, and reduces the risk of postoperative degeneration of adjacent segments. This effectively avoids the soft tissue damage and stress concentration at the vertebral edge that may be caused by the sharp-edged structure of traditional fusion devices, thereby improving patient comfort and safety.

[0044] like Figures 1-8 As shown, based on the above embodiment, the first support surface 310 includes at least two first unit cell planes 311, the first unit cell planes 311 are wavy, and a first connecting groove 312 is provided between two adjacent first unit cell planes 311. The second support surface 320 includes at least two second unit cell planes 321, the second unit cell planes 321 are wavy, and a second connecting groove 322 is provided between two adjacent second unit cell planes 321. When the first support surface 310 and the second support surface 320 overlap, the first connecting groove 312 and the second connecting groove 322 are connected.

[0045] In this embodiment, the combination of the wavy plane and the connecting groove forms a three-dimensional interlocking surface texture, which significantly enhances the friction and shear resistance between the fusion device and the upper and lower vertebral bodies, preventing postoperative slippage. Furthermore, the open channel formed by the connection between the first connecting groove 312 and the second connecting groove 322 facilitates the growth of bone tissue into the fusion device from multiple directions, thereby achieving multidirectional bone integration, accelerating the bone fusion speed, and improving long-term stability.

[0046] like Figures 1-8 As shown, based on the above embodiment, the first unit cell plane 311 in the first connecting groove 312 is projected onto the first support surface 310 and a first connecting hole 313 is provided; the second unit cell plane 321 in the second connecting groove 322 is projected onto the second support surface 320 and a second connecting hole 323 is provided; the first connecting hole 313 and the second connecting hole 323 are connected.

[0047] In this embodiment, a vertical bone ingrowth channel network is constructed by setting connecting holes at the protruding part of the wavy line and achieving the connection between the upper and lower connecting holes. This structure not only enhances the penetrating growth capacity of internal bone tissue, but also increases the bone filling rate inside the fusion device, promotes the integration of internal and external bone, and significantly improves fusion efficiency and biomechanical stability.

[0048] like Figures 1-8 As shown, based on the above embodiment, the projection of the centerline of the first unit cell plane 311 onto the first support surface 310 coincides with the projection of the centerline of the second unit cell plane 321 onto the second support surface 320. The projections of the first unit cell plane 311 onto the first support surface 310 and the second unit cell plane 321 onto the second support surface 320 are symmetrical along their centerlines, thereby causing the first connecting hole 313 and the second connecting hole 323 to be misaligned.

[0049] In this embodiment, a symmetrical but staggered layout of connecting holes is adopted, thus ensuring the connection between the upper and lower channels while forming an interlaced support skeleton structure. This maintains sufficient structural strength, avoids the "weak zone" phenomenon caused by the alignment of the holes, optimizes stress distribution, improves the compressive and fatigue resistance of the overall structure, and still retains a good bone ingrowth path.

[0050] like Figures 1-8 As shown, based on the above embodiment, a first connecting portion 314 is formed between two adjacent first connecting holes 313 in the same first connecting groove 312, and each of the first connecting portions 314 is connected in sequence. A second connecting portion 324 is formed between two adjacent second connecting holes 323 in the same second connecting groove 322, and each of the second connecting portions 324 is connected in sequence. The first connecting portion 314 and the second connecting portion 324 are the same body.

[0051] In this embodiment, the first connecting part 314 and the second connecting part 324 are integral structures, that is, the entire support block 100 is an integrally formed frame with high structural continuity and mechanical integrity, which significantly improves the overall rigidity and deformation resistance of the fusion device, avoids the risk of loosening or breakage that may exist in the splicing structure, and ensures the safety and durability of long-term implantation.

[0052] Specifically, the second stress-bearing component 300 has a three-period minimal surface, which has an extremely high specific surface area, which helps cell attachment, proliferation and differentiation, and the average curvature is zero to avoid stress concentration.

[0053] like Figures 1-8 As shown, based on the above embodiment, the second force-bearing component 300 is an integrally formed component.

[0054] In this embodiment, the second load-bearing component 300 adopts an integral molding process such as additive manufacturing, which eliminates interface defects caused by welding or assembly, and greatly improves the structural reliability and fatigue life of this key load-bearing component.

[0055] It is also worth noting that the second load-bearing structure can adopt a three-period minimal surface structure.

[0056] like Figures 1-8 As shown, based on the above embodiment, the first force-bearing member 200 includes two inclined portions 210 and one vertical portion 220. One end of each of the two inclined portions 210 is connected to one of the two support blocks 100, and the other end of each of the two inclined portions 210 is connected to both ends of the vertical portion 220. The two inclined portions 210 are inclined to the two support blocks 100, and the vertical portion 220 is perpendicular to the support blocks 100.

[0057] In this embodiment, the design of the inclined portion 210 avoids stress concentration caused by the right-angle connection between the support block 100 and the vertical portion 220, allowing the load to be gradually transferred to the vertical portion 220 through an inclined path, significantly reducing local stress peaks and improving the fatigue resistance and long-term durability of the structure. The vertical portion 220 provides sufficient compressive stiffness to maintain the intervertebral disc height, while the inclined portion 210 allows for slight elastic deformation, enabling the fusion device to better adapt to the physiological micro-movements of the spine after implantation, reducing stress shielding effects, and promoting bone tissue growth and fusion process.

[0058] like Figures 1-8 As shown, based on the above embodiment, the number of the first force-bearing member 200 is at least two, and each of the first force-bearing members 200 is distributed around the center of the second force-bearing structure. The inclined part 210 gradually approaches the second force-bearing structure from the end connected to the support block 100 to the end connected to the vertical part 220.

[0059] In this embodiment, multiple first force-bearing components 200 are centrally symmetrically distributed to form a circumferential uniform force field, which enables the load to be uniformly transmitted between the support blocks 100, avoiding local stress concentration. The design of the inclined part 210 converging towards the center further enhances the centripetal constraint of the structure, improves the overall compressive stability and anti-rotation ability, and is particularly suitable for lumbar fusion scenarios that require high stability.

[0060] like Figures 1-8 As shown, based on the above embodiment, the support block 100 is provided with a first bone graft window 110, the second force-bearing member 300 extends toward the first bone graft window 110 and is located in the first bone graft window 110, and the second force-bearing member 300 is provided with a second bone graft window 301.

[0061] In this embodiment, the first bone graft window 110 can accommodate the second force-bearing member 300 and cooperate with the second bone graft window 301 to form a bone graft window that runs vertically through the bone graft, thus constructing a large-capacity, through-type bone graft chamber that can be filled with autologous bone, allogeneic bone, or bone substitute materials. This greatly improves the bone fusion space and bone ingrowth efficiency, which is conducive to the formation of bone bridges across the fusion device, significantly shortens the fusion cycle, and improves the fusion success rate.

Claims

1. A spinal cage, comprising: The application relates to a kind of spinal fusion cages, comprising: Two support blocks, a support space is formed between the two support blocks; A first force structure is located in the support space, the first force structure comprises a first force piece, and the two support blocks are connected by the first force piece; A second force structure comprises two second force pieces, the two second force pieces are located in the support space and connected with the two support blocks respectively, and a contact gap is formed between the two second force pieces; When the two support blocks are pressed, and the two second force pieces are separated, the first force piece exerts force on the two support blocks; when the two support blocks are pressed, and the two second force pieces are in contact, the first force piece and the second force piece simultaneously exert force on the two support blocks; The two surfaces of the second force piece are respectively provided with a first support surface and a second support surface, and the first support surface and the second support surface are smoothly connected; The first support surface comprises at least two first unit planes, the first unit planes are wave-shaped, a first communication groove is arranged between adjacent two first unit planes, the second support surface comprises at least two second unit planes, the second unit planes are wave-shaped, a second communication groove is arranged between adjacent two second unit planes, and the first communication groove and the second communication groove are communicated when the first support surface and the second support surface coincide.

2. The spinal fusion cage of claim 1, wherein: a projection of a protruding part of the first unit plane in the first communication groove on the first support surface is provided with a first communication hole, and a projection of a protruding part of the second unit plane in the second communication groove on the second support surface is provided with a second communication hole, and the first communication hole and the second communication hole are communicated.

3. The spinal fusion cage of claim 2, wherein: a projection of a middle line of the first unit plane on the first support surface coincides with a projection of a middle line of the second unit plane on the second support surface, and the projection of the first unit plane on the first support surface and the projection of the second unit plane on the second support surface are symmetrical along the middle lines of both, so that the first communication hole and the second communication hole are staggered.

4. The spinal fusion cage of claim 3, wherein: a first connecting part is formed between adjacent two first communication holes in the same first communication groove, and each first connecting part is sequentially connected, a second connecting part is formed between adjacent two second communication holes in the same second communication groove, and each second connecting part is sequentially connected, and the first connecting part and the second connecting part are integrated.

5. The spinal fusion cage of claim 4, wherein: the second force piece is an integrated piece.

6. The spinal fusion cage of claim 1, wherein: The first force receiving member comprises two inclined portions and a vertical portion, one end of each of the two inclined portions is connected with one of the two support blocks, the other end of each of the two inclined portions is connected with one end of the vertical portion, the two inclined portions are inclined to the two support blocks respectively, and the vertical portion is perpendicular to the support blocks.

7. A spinal cage according to claim 6, wherein: The number of the first force receiving members is at least two, each of the first force receiving members is distributed around the center of the second force receiving structure, and the inclined portion gradually approaches the second force receiving structure from the end connected with the support block to the end connected with the vertical portion.

8. A spinal cage according to claim 1, wherein: The support block is provided with a first bone graft window, the second force receiving member extends towards and is located in the first bone graft window, and the second force receiving member is provided with a second bone graft window.

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