Low-profile cervical fusion device

Abstract

The utility model discloses a kind of low-cut cervical vertebra fusion ware, belong to orthopedics medical instrument field.The utility model includes fusion ware body and nail plate component, fusion ware body includes top support plate, bottom support plate and porous structure, porous structure is filled and set between top support plate and bottom support plate, fusion ware body is provided with the bone grafting storehouse of penetrating top support plate, porous structure and bottom support plate, bone grafting storehouse and porous structure are communicated, fusion ware body is provided with implantation front end and implantation rear end, implantation rear end is provided with connecting plate mechanism, nail plate component is fixedly set in the implantation rear end of fusion ware body by connecting plate mechanism, nail plate component and fusion ware body are detachably set.The utility model structure design is reasonable, implantation operation is smooth and efficient, implantation use is stable and firm, bone growth effect is good, patient postoperative recovery cycle is short, and can effectively reduce patient postoperative complication, satisfy the need of intervertebral fusion use.

Description

Technical Field

[0001] This utility model belongs to the field of orthopedic medical devices, and in particular relates to a low-notch cervical fusion device. Background Technology

[0002] Intervertebral disc degeneration reduces vertebral stability, leading to various symptoms including neuralgia and functional impairment. A common treatment for disc degeneration is intervertebral fusion (IVM). IVM involves removing the degenerated or necrotic disc and surgically implanting an IVM device into the intervertebral space. This device opens and corrects the distance between the vertebrae, ultimately fusing the adjacent intervertebral segments for greater stability. The IVM device provides support and distributes load effectively, restoring the intervertebral space height and the physiological curvature of the spine. It is an implantable medical device used between the upper and lower vertebrae and is one of the main implants for achieving fusion of adjacent vertebrae. Its safety and effectiveness directly affect the fusion outcome of adjacent vertebrae.

[0003] Existing interbody fusion cages suffer from poor stability during implantation, easily becoming loose, slipping, or dislodging, affecting postoperative recovery and sometimes requiring secondary surgery. Furthermore, current interbody fusion devices exhibit poor bone ingrowth, leading to vertebral non-fusion. Clinical application has revealed that current interbody fusion cage implantation is cumbersome, hindering smooth and efficient placement. The implantation of existing cages requires a separate plate-and-screw system between adjacent vertebrae, resulting in significant incision damage, prolonged recovery, and increased risk of postoperative complications such as spinal cord injury and dysphagia. To achieve smooth and efficient cervical interbody fusion cage implantation, stable and secure placement, improved bone ingrowth, increased fusion efficiency, shorter recovery time, and reduced postoperative complications, a novel cervical interbody fusion cage is needed to address these technical challenges. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to overcome the above-mentioned deficiencies in the prior art and provide a low-notch cervical fusion device with reasonable structural design, smooth and efficient implantation operation, stable and firm implantation, good bone ingrowth effect, short postoperative recovery period for patients, and effective reduction of postoperative complications, which meets the needs of intervertebral fusion.

[0005] To solve the above-mentioned technical problems, the present invention provides a technical solution for a low-notch cervical fusion device: The low-notch cervical fusion device includes a fusion device body and a plate-and-screw assembly. The fusion device body includes a top support plate, a bottom support plate, and a porous structure. The porous structure is filled between the top support plate and the bottom support plate. The top support plate and the bottom support plate have the same structure and are symmetrically arranged. The fusion device body is provided with a bone graft chamber that runs through the top support plate, the porous structure and the bottom support plate. The bone graft chamber and the porous structure are connected. The fusion device body is provided with an implantation front end and an implantation rear end. The implantation rear end is provided with a connecting plate mechanism. The nail plate assembly is fixedly installed at the implantation rear end of the fusion device body through the connecting plate mechanism. The nail plate assembly and the fusion device body are detachably installed.

[0006] Compared with the prior art, this utility model has the following advantages and effects: The utility model has a reasonable structural design, utilizing a porous structure filled between the top and bottom support plates. These plates provide structural strength to the entire fusion device, preventing damage and breakage during implantation. The porous structure enables efficient bone ingrowth and fusion. The fusion device body includes a bone graft chamber, filled with appropriate bone tissue material to aid in bone tissue adhesion and growth, forming a stable bony connection between adjacent vertebrae. The bone graft chamber is connected to the porous structure, allowing for greater contact and ingrowth of bone tissue material with the porous structure on the inner wall of the chamber, shortening the implantation and fusion time and improving the efficiency. The screw-plate assembly is fixed to the rear end of the fusion device body via a connecting plate mechanism, allowing for simultaneous implantation of adjacent vertebrae. Between the vertebrae, the upper and lower ends of the plate assembly can be fixedly connected to the two adjacent vertebrae respectively, ensuring stable and secure implantation. Compared with the separate plate system that accompanies existing interbody fusion devices, the plate assembly of this novel low-notch cervical interbody fusion device is shorter and smaller in size, resulting in less incision damage to the patient during surgery and shortening the postoperative recovery period. At the same time, the incidence of foreign body sensation is reduced during cervical interbody fusion device implantation, effectively reducing postoperative complications such as dysphagia and adjacent vertebral diseases. The plate assembly and the fusion device body are detachable, allowing them to be connected and assembled outside the patient's body before simultaneous implantation, improving the implantation efficiency of this novel low-notch cervical interbody fusion device. The implantation operation is smooth and efficient. In addition, the fusion device body can be implanted with appropriate plate assemblies according to the actual surgical needs, increasing the scope of application and improving the flexibility of combination use to meet the needs of interbody fusion.

[0007] Furthermore, both the top support plate and the bottom support plate are provided with toothed structures on the side away from the porous structure, and the concave part of the toothed structure is in communication with the porous structure.

[0008] Furthermore, the top support plate and the bottom support plate are symmetrically provided with ramp structures along the implantation front end of the fusion device body.

[0009] Furthermore, the connecting plate mechanism at the rear end of the fusion device body includes an anti-rotation groove and a threaded hole. The threaded hole is located in the middle of the rear end of the fusion device body, and the anti-rotation groove is symmetrically arranged on both sides of the threaded hole. The threaded hole communicates with the bone graft chamber.

[0010] Furthermore, the nail plate assembly includes a positioning plate, connecting screws, and positioning screws. The positioning plate has a connecting screw hole in the middle, and the connecting screw is disposed in the connecting screw hole and connected to the threaded hole of the fusion body. The positioning plate has at least one screw hole at each end of the top support plate and the bottom support plate, and the positioning screw is disposed in the screw hole. Anti-rotation blocks that are adapted to the anti-rotation slots are respectively provided on both sides of the positioning plate.

[0011] Furthermore, the positioning plate of the nail plate assembly is provided with locking grooves at both ends, which intersect with the corresponding screw holes. Anti-returning locks are rotatably fitted in the locking grooves to prevent the positioning screws in the screw holes from coming out. The anti-returning locks are provided with anti-returning pressure plates of the same number as the adjacent positioning screws. The locking grooves are provided with riveting holes that are adapted to the anti-returning locks. The anti-returning locks are riveted to the positioning plate using the riveting holes.

[0012] Furthermore, the positioning plate of the nail plate assembly is provided with instrument slots on both sides.

[0013] Furthermore, the top support plate and bottom support plate of the fusion body are provided with screw grooves adapted to the positioning screws along the side surface of the nail plate assembly, and three screw grooves are provided on the top support plate and bottom support plate respectively.

[0014] Furthermore, the porous structure of the low-notch cervical fusion device is a random lattice structure, which includes multiple random lattice units. The structure of the random lattice units includes trabecular bone structure and Thiessen polygonal structure.

[0015] Furthermore, the fusion body of the low-notch cervical fusion device is integrally formed by 3D printing.

[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0018] Figure 1 This is a schematic diagram of the main structure of a low-notch cervical fusion device according to this utility model.

[0019] Figure 2 This is a schematic diagram of the left side of a low-notch cervical fusion device according to this utility model.

[0020] Figure 3 This is a top view schematic diagram of a low-notch cervical fusion device according to this utility model.

[0021] Figure 4 This is a three-dimensional structural diagram of a low-notch cervical fusion device according to this utility model.

[0022] Figure 5 This is a schematic diagram of the main structure of the fusion device body of this utility model.

[0023] Figure 6 This is a three-dimensional structural diagram of the fusion device body of this utility model.

[0024] Figure 7 This is a schematic diagram of the main structure of the nail plate assembly of this utility model.

[0025] Figure 8 This is a three-dimensional structural diagram of the nail plate assembly of this utility model.

[0026] Figure 9 This is a front view structural schematic diagram of an embodiment of the three-positioning screw of this utility model.

[0027] Figure 10 This is a three-dimensional structural schematic diagram of an embodiment of the three-positioning screw of this utility model.

[0028] Figure 11 This is a front view structural schematic diagram of an embodiment of the four-positioning screw of this utility model.

[0029] Figure 12 This is a three-dimensional structural schematic diagram of an embodiment of the four-positioning screw of this utility model.

[0030] In the diagram: 1. Fusion device body, 2. Screw plate assembly, 3. Top support plate, 4. Bottom support plate, 5. Porous structure, 6. Bone graft chamber, 7. Implant front end, 8. Implant rear end, 9. Connecting plate mechanism, 10. Toothed structure, 11. Ramp structure, 12. Anti-rotation slot, 13. Threaded hole, 14. Positioning plate, 15. Connecting screw, 16. Positioning screw, 17. Connecting screw hole, 18. Screw hole, 19. Anti-rotation block, 20. Locking slot, 21. Anti-retraction lock, 22. Anti-retraction pressure plate, 23. Instrument slot, 24. Screw slot. Detailed Implementation

[0031] To further describe the present invention, the following describes a specific embodiment of a low-notch cervical fusion device in conjunction with the accompanying drawings. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0032] This embodiment provides a low-notch cervical fusion device for implantation and fixation of cervical intervertebral fusion. (See also...) Figure 1 , Figure 2 , Figure 3 and Figure 4 The low-notch cervical fusion device includes a fusion device body 1 and a screw-plate assembly 2. The fusion device body 1 includes a top support plate 3, a bottom support plate 4, and a porous structure 5. The porous structure 5 is filled between the top support plate 3 and the bottom support plate 4. The top support plate 3 and the bottom support plate 4 have the same structure and are symmetrically arranged. The top support plate 3 and the bottom support plate 4 can provide structural strength for the entire fusion device body 1, avoiding damage and breakage of the intervertebral fusion device during implantation and use. The porous structure 5 can achieve efficient bone tissue ingrowth and fusion.

[0033] See Figure 5 and Figure 6 The fusion unit body 1 is provided with a bone graft chamber 6 that penetrates the top support plate 3, the porous structure 5, and the bottom support plate 4. The bone graft chamber 6 is filled with appropriate bone tissue material to aid in the attachment and growth of human bone tissue, forming a stable bony connection between adjacent vertebrae. The bone graft chamber 6 and the porous structure 5 are connected, allowing the bone tissue material to contact and grow into the porous structure 5 on a larger area after being filled in the bone graft chamber 6, thus shortening the implantation and fusion time of the intervertebral fusion device and improving its implantation and fusion efficiency. In this embodiment, the shape of the bone graft chamber 6 is not limited; it can be a cylindrical hole, an elliptical cylindrical hole, a regular polygonal prism hole, or an irregular polygonal prism hole.

[0034] The fusion device body 1 is provided with an implantation front end 7 and an implantation rear end 8. The implantation rear end 8 is provided with a connecting plate mechanism 9. The nail plate assembly 2 is fixedly set to the implantation rear end 8 of the fusion device body 1 through the connecting plate mechanism 9. The nail plate assembly 2 and the fusion device body 1 are implanted simultaneously between two adjacent vertebrae. The upper and lower ends of the nail plate assembly 2 can be fixedly connected to the two adjacent vertebrae respectively to ensure stable and firm implantation. Compared with the separate nail plate system that comes with the existing intervertebral fusion device, the nail plate assembly 2 of the low-notch cervical fusion device of this utility model is shorter and smaller in size. The incision damage to the patient during the surgical implantation operation is smaller, shortening the postoperative recovery period. At the same time, the incidence of foreign body sensation is reduced when the cervical fusion device is implanted and used, effectively reducing postoperative complications such as dysphagia and adjacent vertebral disease. The detachable mounting plate assembly 2 and the fusion device body 1 allow for simultaneous implantation of the two components outside the patient's body during the implantation process. This improves the implantation efficiency of the low-notch cervical interbody fusion device of this invention, resulting in a smooth and efficient implantation operation. Furthermore, the fusion device body 1 can be implanted with a suitable mounting plate assembly 2 according to the actual surgical needs, increasing its applicability and flexibility in combination, thus meeting the requirements for interbody fusion.

[0035] In some embodiments, both the top support plate 3 and the bottom support plate 4 have toothed structures 10 on the sides away from the porous structure 5. When the cervical fusion device is implanted, this effectively ensures that the lumbar fusion device is properly engaged and fixed to the two adjacent vertebrae, preventing displacement or tilting of the cervical fusion device during implantation. This allows for stable fixation between adjacent vertebrae, meeting the requirements for intervertebral fusion. The concave portion of the toothed structure 10 communicates with the porous structure 5. The surface of the two adjacent vertebrae of the cervical fusion device is connected to the porous structure 5 via the concave portion of the toothed structure 10, effectively increasing bone ingrowth and improving the implantation and fusion efficiency of the cervical fusion device.

[0036] In some embodiments, the top support plate 3 and the bottom support plate 4 are symmetrically provided with ramp structures 11 along the implantation front end 7 of the fusion body 1. The ramp structure 11 facilitates the surgical implantation of the cervical fusion device, allowing the cervical fusion device to be easily inserted between two adjacent vertebrae during surgical implantation, thus achieving a smooth and efficient surgical implantation operation of the cervical fusion device.

[0037] In some embodiments, the connecting plate mechanism 9 of the implantation rear end 8 of the fusion device body 1 includes an anti-rotation groove 12 and a threaded hole 13. The threaded hole 13 is located in the middle of the implantation rear end 8 of the fusion device body 1, and the anti-rotation groove 12 is symmetrically arranged on both sides of the threaded hole 13. The threaded hole 13 communicates with the bone graft chamber 6. The nail plate assembly 2 can be connected and fixed to the fusion device body 1 through the threaded hole 13. The anti-rotation groove 12 can ensure that the nail plate assembly 2 and the fusion device body 1 do not rotate relative to each other after being connected and fixed, so that the fusion device body 1 and the nail plate assembly 2 can be stably assembled and used.

[0038] See Figure 7 and Figure 8 In some embodiments, the nail plate assembly 2 includes a positioning plate 14, a connecting screw 15 and a positioning screw 16. The positioning plate 14 has a connecting screw hole 17 in the middle. The connecting screw 15 is disposed in the connecting screw hole 17 and connected to the threaded hole 13 of the fusion body 1. The nail plate assembly 2 is connected and fixed to the fusion body 1 by the threaded connection between the connecting screw 15 and the threaded hole 13. The assembly operation is convenient and efficient.

[0039] The positioning plate 14 has at least one screw hole 18 at each end of the top support plate 3 and the bottom support plate 4. The positioning screws 16 are disposed in the screw holes 18. When the cervical fusion device is implanted, the positioning screws 16 at the upper and lower ends of the plate assembly 2 can be threaded and fixed to the two adjacent vertebrae respectively, ensuring stable and secure implantation. The positioning plate 14 has anti-rotation blocks 19 on both sides that are adapted to the anti-rotation slots 12. When the plate assembly 2 is connected and assembled with the fusion device body 1, the anti-rotation blocks 19 of the plate assembly 2 and the anti-rotation slots 12 of the fusion device body 1 are engaged and connected, ensuring that the plate assembly 2 and the fusion device body 1 do not rotate relative to each other after connection and fixation, so that the low-notch cervical fusion device of this utility model can be stably implanted and used.

[0040] Compared to the separate nail-plate system that accompanies the implantation of existing interbody fusion devices, the nail-plate assembly 2 of this invention is shorter and smaller in size, resulting in less incision damage to the patient during surgical implantation and shortening the postoperative recovery period. At the same time, the incidence of foreign body sensation is reduced when the cervical fusion device is implanted, effectively reducing postoperative complications such as dysphagia and adjacent vertebral diseases.

[0041] In some embodiments, the positioning plate 14 of the nail plate assembly 2 is provided with locking grooves 20 at both ends, which intersect with the corresponding screw holes 18. Anti-retraction locking buckles 21 are rotatably fitted within the locking grooves 20 to prevent the positioning screws 16 in the screw holes 18 from retracting. The anti-retraction locking buckles 21 are provided with anti-retraction pressure plates 22, the same number as the adjacent positioning screws 16. The locking grooves 20 are provided with riveting holes adapted to the anti-retraction locking buckles 21. The anti-retraction locking buckles 21 are riveted to the positioning plate 14 using the riveting holes. When the cervical fusion device is implanted, the anti-retraction locking buckles 21 rotate at a certain angle along the locking grooves 20 under the operation of the surgical instruments. The anti-retraction pressure plates 22 of the anti-retraction locking buckles 21 are located in the exit channel of the positioning screws 16, effectively preventing the positioning screws 16 in the screw holes 18 from retracting, thus improving the safety of the low-notch cervical fusion device implantation of this invention.

[0042] See Figure 9 , Figure 10 , Figure 11 and Figure 12The nail plate assembly 2 includes a two-positioning screw 16 nail plate assembly 2, a three-positioning screw 16 nail plate assembly 2, and a four-positioning screw 16 nail plate assembly 2. For the two-positioning screw 16 nail plate assembly 2, a positioning screw 16 is provided at each end of the nail plate assembly 2, and an anti-reverse locking buckle 21 is provided at each end of the nail plate assembly 2. Each anti-reverse locking buckle 21 at each end of the nail plate assembly 2 is provided with an anti-reverse pressure plate 22, the same number as the adjacent positioning screw 16. For the three-positioning screw 16 nail plate assembly 2, one positioning screw 16 and two positioning screws 16 are respectively provided at both ends of the nail plate assembly 2. An anti-retraction latch 21 is provided at both ends of the nail plate assembly 2. At the end of one positioning screw 16, the anti-retraction latch 21 is provided with one anti-retraction pressure plate 22, which is the same number as the adjacent positioning screw 16. At the ends of two positioning screws 16, the anti-retraction latch 21 is provided with two anti-retraction pressure plates 22, which are the same number as the adjacent positioning screws 16. By rotating the anti-retraction latch 21, the two anti-retraction pressure plates 22 on the anti-retraction latch 21 can be simultaneously positioned in the exit channel of the two positioning screws 16. For the four positioning screws 16 nail plate assembly 2, two positioning screws 16 are respectively provided at both ends of the nail plate assembly 2, and an anti-retraction latch 21 is provided at both ends of the nail plate assembly 2. The anti-retraction latch 21 is provided with two anti-retraction pressure plates 22, which are the same number as the adjacent positioning screws 16. By rotating the anti-retraction latch 21, the two anti-retraction pressure plates 22 on the anti-retraction latch 21 can be simultaneously positioned in the exit channel of the two positioning screws 16.

[0043] In some embodiments, the positioning plate 14 of the nail plate assembly 2 is provided with instrument slots 23 on both sides. The instrument slots 23 can be adapted to the implantation surgical clamp to ensure that the cervical fusion device can be stably and firmly clamped and fixed by the implantation surgical clamp. The cervical fusion device can be surgically implanted under the clamping action of the clamp, realizing a smooth and efficient surgical implantation operation of the cervical fusion device.

[0044] In some embodiments, the top support plate 3 and bottom support plate 4 of the fusion device body 1 are provided with screw grooves 24 adapted to the positioning screws 16 along the side surfaces of the plate-and-screw assembly 2. After passing through the screw holes 18 of the positioning plate 14, the positioning screws 16 can be fixedly connected to the adjacent vertebral bodies along the screw grooves 24. The screw body portion of the positioning screw 16 is located within the screw grooves 24. The screw grooves 24 can effectively reduce the length and volume of the positioning plate 14 of the plate-and-screw assembly 2. The smaller plate-and-screw assembly 2 can cause less incision damage to the patient during surgical implantation, shortening the postoperative recovery period. At the same time, when the cervical fusion device is implanted, the incidence of foreign body sensation is reduced, effectively reducing postoperative complications such as dysphagia and adjacent vertebral diseases. The top support plate 3 and bottom support plate 4 are each provided with three screw grooves 24, so that the same type of fusion device body 1 can be adapted to different types of plate-and-screw assemblies 2, increasing the scope of application and improving the flexibility of combination use.

[0045] In some embodiments, the porous structure 5 of the low-notch cervical fusion device is a random lattice structure. The random lattice structure can improve the bone ingrowth effect of the cervical fusion device, and the random lattice structure can make the elastic modulus of the cervical fusion device close to the elastic modulus of human bone, thus avoiding stress shielding of the cervical fusion device during implantation and use.

[0046] The random lattice structure includes multiple random lattice units. The structure of the random lattice unit includes a trabecular structure and a Thiessen polygonal structure. The random lattice unit contains at least three link structures. The link structures are connected end to end to form a polygon. The polygon includes, but is not limited to, triangles, quadrilaterals, pentagons, hexagons, and heptagons.

[0047] The linkage structure forms nodes at its connection points. The nodes of two adjacent polygons coincide, and in multiple random lattice units, the linkage structures of two adjacent random lattice units coincide. The porosity of the random lattice structure is the ratio of the volume of the pore portion between the linkage structures to the volume of the random lattice structure itself. The porosity of the random lattice structure ranges from 5% to 95%. The pore portions between the linkage structures are through holes, with pore diameters ranging from 100 μm to 800 μm. The diameter, length, and number of linkages in the random lattice structure collectively control its porosity. By adjusting the porosity, the elastic modulus of the random lattice structure is made close to that of human bone. The linkage diameter of the random lattice structure ranges from 100 μm to 400 μm, and the linkage length ranges from 100 μm to 2000 μm. When the elastic modulus of the interbody fusion device is close to that of human bone, stress shielding and other problems can be avoided. When the elastic modulus of the interbody fusion device is different from that of human bone, the interbody fusion device will cause stress shielding after implantation, resulting in bone resorption, which in turn will loosen the interbody fusion device and cause implantation failure.

[0048] In some embodiments, the fusion body 1 of the low-notch cervical fusion device is manufactured in one piece by 3D printing, which is efficient in product processing and precise in dimensional manufacturing.

[0049] In practical use, the cervical fusion device of this utility model has an anti-retraction lock 21 riveted into the riveting hole of the screw plate assembly 2. The anti-retraction pressure plate 22 of the anti-retraction lock 21 is not located in the screw hole 18. The connecting screw 15 is placed in the connecting screw hole 17 and connected to the threaded hole 13 of the fusion device body 1. The anti-rotation blocks 19 on both sides of the positioning plate 14 are connected with the anti-rotation groove 12 of the fusion device body 1 to realize the connection and fixation between the screw plate assembly 2 and the fusion device body 1. The implanted surgical clamp uses the instrument slot 23 to hold the cervical spine. The fusion device is stably and securely clamped and fixed, enabling the surgical implantation of the cervical fusion device. After the cervical fusion device is implanted and placed in the required intervertebral position, the positioning screw 16 passes through the screw hole 18 of the positioning plate 14 and is fixedly connected to the adjacent vertebral body. The anti-retraction lock 21 rotates at a certain angle along the lock groove 20 under the operation of the surgical instruments. The anti-retraction pressure plate 22 of the anti-retraction lock 21 is located in the exit channel of the positioning screw 16, preventing the positioning screw 16 in the screw hole 18 from coming out, thus completing the implantation operation of the low-notch cervical fusion device of this utility model.

[0050] The above description in this specification is merely illustrative of the present 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 replace them, as long as they do not depart from the content of this specification or exceed the scope defined in the claims, all of which shall fall within the protection scope of this invention.

Claims

1. A low-notch cervical fusion device, characterized in that: The low-notch cervical fusion device includes a fusion device body (1) and a plate-and-screw assembly (2). The fusion device body (1) includes a top support plate (3), a bottom support plate (4), and a porous structure (5). The porous structure (5) is filled between the top support plate (3) and the bottom support plate (4). The top support plate (3) and the bottom support plate (4) have the same structure and are symmetrically arranged. The fusion body (1) is provided with a bone graft chamber (6) that penetrates the top support plate (3), the porous structure (5) and the bottom support plate (4). The bone graft chamber (6) and the porous structure (5) are connected. The fusion device body (1) is provided with an implantation front end (7) and an implantation back end (8). The implantation back end (8) is provided with a connecting plate mechanism (9). The nail plate assembly (2) is fixedly installed on the implantation back end (8) of the fusion device body (1) through the connecting plate mechanism (9). The nail plate assembly (2) and the fusion device body (1) are detachably installed.

2. The low-notch cervical fusion device according to claim 1, characterized in that: The top support plate (3) and the bottom support plate (4) are both provided with toothed structures (10) on the side away from the porous structure (5), and the concave part of the toothed structure (10) is connected to the porous structure (5).

3. A low-notch cervical fusion device according to claim 1 or 2, characterized in that: The top support plate (3) and the bottom support plate (4) are symmetrically provided with ramp structures (11) along the implantation front end (7) of the fusion body (1).

4. The low-notch cervical fusion device according to claim 1, characterized in that: The connecting plate mechanism (9) of the fusion body (1) implanted at the rear end (8) includes an anti-rotation slot (12) and a threaded hole (13). The threaded hole (13) is located in the middle of the fusion body (1) implanted at the rear end (8). The anti-rotation slot (12) is symmetrically arranged on both sides of the threaded hole (13). The threaded hole (13) is connected to the bone graft chamber (6).

5. A low-notch cervical fusion device according to claim 4, characterized in that: The nail plate assembly (2) includes a positioning plate (14), a connecting screw (15) and a positioning screw (16). The positioning plate (14) has a connecting nail hole (17) in the middle. The connecting screw (15) is located in the connecting nail hole (17) and connected to the threaded hole (13) of the fusion body (1). The positioning plate (14) has at least one screw hole (18) at each end of the top support plate (3) and the bottom support plate (4). The positioning screw (16) is located in the screw hole (18). The positioning plate (14) has anti-rotation blocks (19) that are adapted to the anti-rotation slot (12) on both sides.

6. A low-notch cervical fusion device according to claim 5, characterized in that: The positioning plate (14) of the nail plate assembly (2) is provided with locking grooves (20) at both ends, which intersect with the corresponding screw holes (18). The locking groove (20) is rotatably fitted with an anti-returning lock (21) to prevent the positioning screw (16) in the screw hole (18) from coming out. The anti-returning lock (21) is provided with an anti-returning pressure plate (22) with the same number as the adjacent positioning screw (16). The locking groove (20) is provided with a riveting hole that matches the anti-returning lock (21). The anti-returning lock (21) is riveted to the positioning plate (14) by means of the riveting hole.

7. A low-notch cervical fusion device according to claim 5 or 6, characterized in that: The positioning plate (14) of the nail plate assembly (2) is provided with instrument slots (23) on both sides.

8. A low-notch cervical fusion device according to claim 5, characterized in that: The top support plate (3) and bottom support plate (4) of the fusion body (1) are provided with screw grooves (24) that are compatible with the positioning screws (16) along the side surface of the nail plate assembly (2). The top support plate (3) and bottom support plate (4) are respectively provided with three screw grooves (24).

9. A low-notch cervical fusion device according to claim 1 or 5, characterized in that: The porous structure (5) of the low-notch cervical fusion device is a random lattice structure, which includes multiple random lattice units. The structure of the random lattice units includes trabecular bone structure and Thiessen polygonal structure.

10. A low-notch cervical fusion device according to claim 9, characterized in that: The fusion body of the low-notch cervical fusion device is manufactured in one piece by 3D printing.

Images