Zero-profile biomimetic cervical interbody fusion cage

Abstract

The utility model provides a kind of zero-cut biomimetic cervical vertebra fusion ware, it is related to medical instrument field. Including integrally formed fusion ware body, fusion ware body includes fixed part and fusion part of mutual link;Fixed part is arranged at fusion part one end, it is provided with two towards its opposite sides reverse extension connecting piece, two connecting pieces are used to connect with adjacent two vertebral body respectively;Fusion part middle part is equipped with through-hole, its facing adjacent two vertebral body upper and lower end face is provided with nanometer groove array and micropore array;Wherein, micropore array penetrates its upper and lower end face. The application can realize stable implantation, not easy to loosen and exit, and efficiently promote bone fusion, help bone tissue to grow in.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, specifically to a zero-notch bionic cervical fusion device. Background Technology

[0002] Anterior cervical spine surgery is a common treatment for cervical spondylosis, with cervical discectomy and fusion being the most common procedure. Traditional fusion techniques, primarily using anterior titanium plates combined with a cage, have become mainstream. However, this approach carries risks such as screw loosening leading to fusion failure and stress concentration in adjacent segments causing adjacent vertebral lesions. Zero-notch fusion cages integrate the cage and fixation screws into a single design, effectively reducing irritation to the esophagus and soft tissues, significantly decreasing the incidence of adjacent vertebral lesions, and thus gaining widespread clinical preference.

[0003] However, traditional zero-notch fusion devices are prone to loosening and failure, and have poor fusion. With the physiological activities of the human body, the pressure on the bone in the fusion area will increase, causing fracture of the intervertebral fusion bone and leading to instability of the cervical vertebrae. Utility Model Content

[0004] The purpose of this invention is to provide a zero-notch bionic cervical fusion device that can achieve stable implantation, efficiently promote bone fusion, and facilitate bone tissue ingrowth.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A zero-notch bionic cervical fusion device includes an integrally formed fusion device body, wherein the fusion device body includes a fixing part and a fusion part that are connected to each other;

[0007] The fixing part is provided at one end of the fusion part, and it is provided with two connectors that extend in opposite directions toward its opposite sides. The two connectors are respectively used to connect with two adjacent vertebral bodies.

[0008] The fusion section has a through hole in the middle, and the upper and lower end faces of the fusion section facing the adjacent two vertebrae are provided with a nanoscale groove array and a micropore array; wherein, the micropore array runs through the upper and lower end faces.

[0009] Furthermore, in this utility model, the upper and lower end faces of the fusion device body are dome-shaped to fit the adjacent vertebrae.

[0010] The width of the fusion portion at the end away from the fixing portion is smaller than the width of the fixing portion, and the connection between the two is a rounded transition.

[0011] Furthermore, in this invention, the nanoscale trench array includes multiple nanogrooves arranged along the implantation direction, and the multiple nanogrooves are arranged to form a surface tooth-like structure.

[0012] Furthermore, in this invention, the plurality of nanogrooves are arranged horizontally along the implantation direction; or at least some of the nanogrooves are arranged obliquely relative to the implantation direction, forming a tapered tooth structure that gradually narrows from the fixation part to the fusion part.

[0013] Furthermore, in this utility model, the connector includes a double-thread screw; the tail end of the double-thread screw is provided with a thread density gradually increasing region, and the thread of the double-thread screw is in the form of a stacked wall.

[0014] The fixing part is provided with two screw holes at horizontal intervals, which are used to insert the two double-wire screws respectively; wherein, the angle between the axis of the screw hole and the horizontal axis of the fusion part is 30-45°.

[0015] Furthermore, in this invention, the fixing part is rotatably provided with an anti-retraction locking piece along the implantation direction;

[0016] The anti-reverse locking plate is elliptical in shape, or the head of the anti-reverse locking plate is provided with a reverse-extending bulge, so as to limit and block the two connecting pieces.

[0017] Furthermore, in this utility model, the fusion body is made of PEEK material; the double-wire screw is made of PEEK material or metal material; and the anti-reverse locking plate is made of titanium-nickel alloy material.

[0018] Furthermore, in this invention, the edge of the fixing part is provided with a wing extending toward two adjacent vertebral segments.

[0019] Furthermore, in this utility model, the two ends of the fixing part are respectively provided with slots, which are used for tool clamping.

[0020] Furthermore, in this invention, the upper and lower end faces of the fusion portion are respectively coated with a hydroxyapatite coating or a tantalum metal bioactive coating.

[0021] This utility model has at least the following advantages or beneficial effects:

[0022] This invention features a one-piece fusion device body comprising an interconnected fixation part and a fusion part, implanted between two adjacent vertebral bodies. The fixation part has two counter-extending connectors for connecting to the adjacent vertebral bodies, achieving stable implantation. A through-hole in the center of the fusion part allows for the implantation of autologous or allogeneic bone, promoting fusion with the adjacent vertebral bodies. Nanoscale groove arrays and micropore arrays are respectively formed on the upper and lower end faces of the fusion part. The micropore array penetrates the upper and lower end faces, aligning with the direction of the trabecular bone, which better promotes trabecular bone growth and accelerates bone fusion. The nanoscale groove array not only works in conjunction with the micropore array to promote bone ingrowth but also acts as a barrier to prevent retraction from the fusion part. This invention achieves stable implantation, is less prone to loosening or retraction, and efficiently promotes bone fusion, facilitating bone ingrowth. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the zero-notch bionic cervical fusion device provided in the application embodiment;

[0025] Figure 2 A cross-sectional view of the cervical fusion device provided in the application embodiment.

[0026] Reference numerals: 1-Fusion unit body, 11-Fixing part, 111-Screw hole, 112-Wing plate, 113-Slot, 12-Fusion part, 121-Through hole, 13-Connector, 131-Double-wire screw, 14-Nano-scale groove array, 141-Nano groove, 15-Micropore array, 151-Micropore channel, 16-Anti-reverse locking plate. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0029] Example

[0030] Please refer to Figures 1-2 The figure shown is a schematic diagram of the zero-notch bionic cervical fusion device in an embodiment of this utility model.

[0031] This embodiment provides a zero-notch bionic cervical fusion device, comprising an integrally molded fusion device body 1. The fusion device body 1 is 3D printed from PEEK material, facilitating individualized design and fabrication. Clinical application allows for personalized matching to different individuals and vertebral segments. Being entirely made of PEEK material, it shares the same mechanical properties as human bone, avoiding stress shielding at the bone-material interface and preventing postoperative collapse. This solves the problems of mismatch between the mechanical strength of metal materials or metal-PEEK hybrid materials in zero-notch fusion devices, leading to postoperative endplate collapse and subsidence. The fusion device body 1 consists of an interconnected fixation part 11 and a fusion part 12, both positioned between two adjacent vertebral bodies. The fixation part 11 is located at one end of the fusion part 12 and has two connecting members 13 extending in opposite directions to its opposite sides. The two connecting members 13 are used to connect to the two adjacent vertebral bodies respectively for fixation. The fusion section 12 has a through-hole 121 in the middle, which, aligned with the direction of the upper and lower vertebral bodies, allows for the implantation of autologous or allogeneic bone. After implantation, the fusion device promotes fusion with the upper and lower vertebral bodies. The fusion section 12 has a nanoscale groove array 14 and a micropore array 15 on both the upper and lower end faces of the adjacent vertebral bodies. The micropore array 15 penetrates both end faces and is aligned with the direction of the trabeculae of the upper and lower vertebrae, which better promotes trabecular bone growth and accelerates bone fusion. Specifically, the micropore array 15 is formed by arranging several micropore channels 151. The nanoscale groove array 14 and the micropore array 15 work together to not only promote bone ingrowth but also create an uneven surface on the upper and lower end faces of the fusion section 12, increasing friction with the vertebral bodies, preventing them from retracting, and thus improving the implantation stability of the fusion device body 1.

[0032] It should be noted that the above-mentioned nanoscale trench array 14 and micropore array 15 are both formed by 3D printing, which is simple and quick to manufacture, and the pore size is easy to control and adjust. The resulting porous structure can efficiently promote bone tissue ingrowth.

[0033] As an example, the upper and lower end faces of the aforementioned fusion portion 12 are respectively coated with a hydroxyapatite coating or a tantalum metal bioactive coating. The porous structure, such as the surface voids formed by the aforementioned nanoscale groove array 14 and micropore array 15, facilitates the filling of the coating, thereby promoting osseointegration and osteoinduction of the fusion device, helping to promote bone healing, and avoiding the risk of fusion surgery failure.

[0034] As an example, the upper and lower end faces of the aforementioned fusion device body 1 are dome-shaped to fit adjacent vertebral bodies; both the fusion portion 12 and the fixation portion 11 are wedge-shaped, with the width of the end of the fusion portion 12 away from the fixation portion 11 (front end) being smaller than the width of the fixation portion 11 (rear end), and there is a 3-5 angular difference between the front and rear ends, which can maintain the physiological lordosis of the cervical spine after implantation. Since the curvature of the upper and lower surfaces of the fusion portion 12 may be different, markings can be set to distinguish the upper and lower surfaces to facilitate implantation during surgery. The connection between the fusion portion 12 and the fixation portion 11 is an arc transition, which facilitates implantation and avoids damage to bone tissue. Through the above structural design, the fusion device body 1 can match the morphology of the vertebral endplate, maintain the physiological curvature of the spine, and the endplate of a normal intervertebral disc has an arc-shaped structure that is higher in the front and lower in the back. The dome-shaped design can better fit the natural anatomical shape of the vertebral endplate, promote bone fusion, and evenly distribute the load.

[0035] As an example, the above-mentioned nanoscale groove array 14 includes multiple nanogrooves 141 arranged along the implantation direction. The multiple nanogrooves 141 are arranged to form a surface tooth-like structure, which not only helps the bone tissue of the upper and lower vertebrae to fuse, but the uneven surface tooth-like structure formed can also block the fusion part 12, prevent it from sliding and retracting, thereby improving its implantation stability.

[0036] As an example, the aforementioned plurality of nanogrooves 141 may be arranged horizontally along the implantation direction; or at least some of the nanogrooves 141 may be arranged at an angle of 5° to 15° relative to the implantation direction, forming a tapered toothed structure that tapers from the fixing part 11 to the fusion part 12. Specifically, the nanogrooves 141 around the through hole 121 may be arranged at an angle, or all of them may be arranged at an angle, forming a tapered toothed structure opposite to the implantation direction, thereby blocking the fusion device.

[0037] Furthermore, the diameter of the nanogroove 141 can be gradually reduced from the center to the edge, and the micropore array 15 can be a trapezoidal micropore array 15, that is, the pore diameter of the micropore array 15 can be gradually reduced from the center to the edge, which improves the fusion effect and enhances the edge strength.

[0038] As an example, the aforementioned connector 13 includes a double-threaded screw 131, which has two separate spiral threads, improving implantation speed and initial stability. The tail end of the double-threaded screw 131 features a gradually increasing thread density zone; as the screw is screwed in to its end, the thread density increases, tightening the connection with the vertebrae and enhancing stability. The threads of the double-threaded screw 131 are trapezoidal, with a tooth crest width to tooth height ratio of 1:1.2 to 1:1.5. After implantation, the screw generates an axial preload of 50-150N through the thread taper difference, achieving self-locking pressure fixation between the upper and lower vertebrae and the fusion cage body 1, allowing for automatic pressure locking of the upper and lower vertebrae and the fusion cage after implantation. This self-locking pressure screw significantly reduces postoperative subsidence by locking the upper and lower vertebrae to the implant. The double-threaded screw 131 has a diameter of 4.0mm and is available in lengths of 12cm, 14cm, 16cm, and 18cm.

[0039] The aforementioned fixation part 11 is provided with two screw holes 111 at horizontal intervals. The double-wire screw 131 is rotated into the upper and lower vertebral bones through the two screw holes 111 of the fixation part 11 to fix the implant. The angle between the axis of the screw hole 111 and the horizontal axis of the fusion part 12 is 30-45° to maintain a stable connection and prevent it from falling off.

[0040] Furthermore, the aforementioned double-wire screw 131 is made of PEEK material or metal material, preferably PEEK material, which eliminates the need for accessory metal fixation components, greatly simplifying the operation steps, saving surgical time, and reducing bleeding.

[0041] As an example, the aforementioned fixing part 11 is rotatably fitted with an anti-retraction locking piece 16 along the implantation direction. The anti-retraction locking piece 16 is elliptical in shape, or its head is provided with a counter-extending enlarged portion to limit and block the two connecting pieces 13. The aforementioned anti-retraction locking piece 16 can be threaded through the middle of the fixing part 11, or it can be limited and embedded in the fixing part 11, so that it can only rotate a certain angle (such as 90°). Specifically, when the aforementioned double-wire screw 131 is screwed in, the anti-retraction locking piece 16 is placed vertically in the length direction. After screwing in, rotating the anti-retraction locking piece 16 by 90 degrees causes the enlarged portions at both ends to block the tail of the double-wire screw 131, preventing the screw from retracting or loosening.

[0042] Furthermore, the anti-reverse locking plate 16 is made of titanium-nickel alloy. Titanium-nickel alloy is in the austenitic phase at body temperature (~37℃) and has a recoverable strain capacity of 6-8%. When the screw is subjected to vibration or fretting, the anti-reverse locking plate 16 can absorb energy through elastic deformation and return to its original shape after the external force is removed, maintaining a constant locking force.

[0043] As an example, the edge of the aforementioned fixation part 11 is provided with a wing 112 extending toward the two adjacent vertebral bodies. After being inserted, it is pressed against the surface of the vertebral bone to prevent the fusion device from entering the spinal canal and compressing the nerve.

[0044] As an example, the two ends of the fixing part 11 are respectively provided with slots 113, which are used for tool clamping to facilitate tool handling during surgery.

[0045] As an example, arrow indicators can be provided on both sides of the rear end face of the aforementioned fixation part 11 to mark the direction of implantation during surgery.

[0046] The beneficial effects of the embodiments of this application are as follows:

[0047] This interbody fusion device is designed and manufactured using 3D printing, allowing for personalized matching of different individuals and segments in clinical applications.

[0048] This fusion device has zero incision and does not require additional screws or plates for fixation, which greatly reduces the occurrence of dysphagia and foreign body sensation after surgery.

[0049] This fusion device features an integrated design that eliminates the need for additional metal fixation components, greatly simplifying the procedure, saving surgical time, and reducing bleeding.

[0050] The dome-shaped biomimetic design of the fusion device matches the contact surfaces of the upper and lower endplates of the human cervical spine, which helps bone fusion and reduces complications from loosening failure.

[0051] The fusion device is made entirely of PEEK material, which has the same mechanical properties as human bone, avoiding stress shielding at the bone-material interface and preventing postoperative collapse.

[0052] The PEEK material of this intervertebral fusion device is 3D printed into a porous structure consisting of a micropore array 15 arranged in different directions and a nano-groove array 14, which helps bone tissue ingrowth. At the same time, coatings such as hydroxyapatite or tantalum metal can be made on the surface and in the pores of the material, which greatly promotes bone fusion.

[0053] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A zero-notch bionic cervical fusion device, characterized in that, It includes an integrally formed fusion body, the fusion body comprising a fixing part and a fusion part that are connected to each other; The fixing part is provided at one end of the fusion part, and it is provided with two connectors that extend in opposite directions toward its opposite sides. The two connectors are respectively used to connect with two adjacent vertebral bodies. The fusion section has a through hole in the middle, and the upper and lower end faces of the fusion section facing the adjacent two vertebrae are provided with a nanoscale groove array and a micropore array; wherein, the micropore array runs through the upper and lower end faces.

2. The zero-notch bionic cervical fusion device according to claim 1, characterized in that, The upper and lower end faces of the fusion device body are dome-shaped to fit the adjacent vertebrae; The width of the fusion portion at the end away from the fixing portion is smaller than the width of the fixing portion, and the connection between the two is a rounded transition.

3. The zero-notch bionic cervical fusion device according to claim 1, characterized in that, The nanoscale trench array includes multiple nanogrooves arranged along the implantation direction, and the multiple nanogrooves are arranged to form a surface tooth-like structure.

4. The zero-notch bionic cervical fusion device according to claim 3, characterized in that, The plurality of nanogrooves are arranged horizontally along the implantation direction; or at least some of the nanogrooves are arranged at an angle relative to the implantation direction, forming a tapered tooth structure that gradually narrows from the fixation part to the fusion part.

5. The zero-notch bionic cervical fusion device according to claim 1, characterized in that, The connector includes a double-thread screw; the tail end of the double-thread screw is provided with a thread density gradually increasing region, and the thread of the double-thread screw is in the form of a bastion. The fixing part is provided with two screw holes at horizontal intervals, which are used to insert the two double-wire screws respectively; wherein, the angle between the axis of the screw hole and the horizontal axis of the fusion part is 30-45°.

6. The zero-notch bionic cervical fusion device according to claim 5, characterized in that, The fixing part is rotatably provided with an anti-retraction locking plate along the implantation direction; The anti-reverse locking plate is elliptical in shape, or the head of the anti-reverse locking plate is provided with a reverse-extending bulge, so as to limit and block the two connecting pieces.

7. The zero-notch bionic cervical fusion device according to claim 6, characterized in that, The fusion unit body is made of PEEK material; the double-wire screw is made of PEEK material or metal material; the anti-reverse locking plate is made of titanium-nickel alloy material.

8. The zero-notch bionic cervical fusion device according to claim 1 or 6, characterized in that, The edge of the fixing part is provided with winglets extending toward the two adjacent vertebrae.

9. The zero-notch bionic cervical fusion device according to claim 1, characterized in that, The fixing part has slots at both ends, which are used for tool clamping.

10. The zero-notch bionic cervical fusion device according to claim 1, characterized in that, The upper and lower surfaces of the fusion section are respectively coated with a hydroxyapatite coating or a tantalum metal bioactive coating.

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