Bone screw anti-retreating device

Abstract

The utility model provides a bone screw anti-retreating device which comprises a fusion assembly, a plurality of screw channels are formed in the fusion assembly, the fusion assembly and the anti-retreating assembly are integrally formed, and the anti-retreating assembly is arranged between the screw channels and used for preventing screws from retreating in the service process of the fusion assembly. Compared with an anti-retreating structure adopted by an existing self-fixing interbody fusion cage, the self-fixing interbody fusion cage has the advantages that an anti-retreating assembly does not need to be machined independently, the assembling steps between the anti-retreating assembly and the fusion assembly are reduced, and cost is saved.

Description

Technical Field

[0001] The present application belongs to the technical field of medical devices, and in particular, relates to a bone screw anti-retraction device. Background Art

[0002] Spinal interbody fusion is an important method for treating cervical and lumbar degenerative diseases. The operation relieves the compression of nerve root tissue by removing protruding disc tissue and osteophytes, and restores the structural stability of the spine. The interbody fusion cage is a key device in this operation, which plays a role in maintaining vertebral stability, expanding the space and restoring intervertebral height.

[0003] With the advancement of surgical technology and the iteration and update of products, self-fixing intervertebral fusion devices (also known as zero-profile intervertebral fusion devices) have been applied to spinal intervertebral fusion. Self-fixing intervertebral fusion devices do not require the use of steel plates for fixation. They are directly fixed through their own fixation devices, do not protrude the front edge of the vertebral body, can reduce damage to the prevertebral soft tissue and adjacent intervertebral discs, and can effectively prevent postoperative complications.

[0004] At present, most self-fixing intervertebral fusion devices use fixing screws to fix the fusion device body to the adjacent vertebral bodies. As time goes by, there is a risk of screws being loosened and retracted. Existing self-fixing intervertebral fusion devices mainly use the following three methods to prevent screws from being retracted. The first is that, for example, the product Zero-P VA uses a spring and a spiral tube to prevent screws from being retracted. The second is that, for example, the product Divergence uses a rotary blade to prevent screws from being retracted. The third is that, for example, the product Anchor-C uses a slot designed in the screw channel and a clamping ring installed at the screw head to prevent screws from being retracted.

[0005] However, the structures used in the above three methods to prevent the screws from withdrawing often require machining and need to be assembled with the fusion device body during the manufacturing process or even during the operation. Since the intervertebral fusion device itself is small in size, the size of the structure to prevent the screws from withdrawing is also very small, and its manufacturing and assembly are difficult, which will also cause inconvenience to the doctor's surgical operation. As for the second method of using a rotary vane to prevent the screws from withdrawing, the anti-withdrawal screw needs to be screwed into the fusion device body. This method will cause certain wear and tear on the rotary vane itself and the fusion device body, which is not conducive to ensuring the service life of the rotary vane and the fusion device body. In addition, the rotary vane is prone to not rotating in place or rotating too much, requiring the doctor to adjust it during the operation. Utility Model Content

[0006] 1. Technical problems to be solved

[0007] The existing structures for preventing screw withdrawal often require machining and need to be assembled with the fusion device body during the manufacturing process or even during the operation. Since the intervertebral fusion device itself is small in size, the size of the structure for preventing the screw from withdrawing is also very small, making it difficult to manufacture and assemble, which will also cause inconvenience to the doctor's surgical operation. As for the second method of using a rotary vane to prevent the screw from withdrawing, the anti-withdrawal screw needs to be screwed into the fusion device body. This method will cause certain wear and tear on the rotary vane itself and the fusion device body, which is not conducive to ensuring the service life of the rotary vane and the fusion device body. In addition, the rotary vane is prone to not rotating in place or rotating too far, requiring the doctor to adjust it during the operation. The present application provides a bone screw anti-withdrawal device.

[0008] 2. Technical solution

[0009] In order to achieve the above-mentioned purpose, the present application provides a bone screw anti-retraction device, including a fusion component, on which a plurality of screw channels are arranged, the fusion component and the anti-retraction component are integrally formed, the anti-retraction component is arranged between the screw channels, and the anti-retraction component is used to prevent the screw from retreating during the service of the fusion component.

[0010] Another implementation manner provided by the present application is that the anti-retraction assembly includes a baffle, a rotating shaft and a locking mechanism connected in sequence.

[0011] Another embodiment provided by the present application is: a stepped hole is provided on the fusion component, there are two screw channels, the stepped hole is provided between the two screw channels, the rotating shaft is provided in the stepped hole, and the locking mechanism is provided in the stepped hole.

[0012] Another embodiment provided by the present application is: a plurality of elastic grooves are provided on the locking mechanism, a plurality of latching protrusions are provided on both sides of the locking mechanism, the elastic groove holes are deformed so that the latching protrusions can engage with the arc grooves, and a plurality of the arc grooves are provided on the stepped holes.

[0013] Another implementation manner provided by the present application is that a countersunk hole is provided on the baffle plate, and the position of the anti-retraction component is adjusted through the countersunk hole.

[0014] Another implementation manner provided by the present application is that the diameter of the locking mechanism is larger than the rotating shaft, and the elastic groove is in an arc shape.

[0015] Another implementation manner provided by the present application is that the locking protrusion is semi-elliptical, semi-circular or triangular; and the countersunk hole is in the shape of a straight line, a triangle, a cross, an inner hexagon or a plum blossom.

[0016] Another embodiment provided by the present application is: the fusion component includes a limit block, a clamping groove, a porous structure and a bone grafting window; there are two limit blocks, and the limit blocks are arranged at the diagonal position of the front side of the fusion component; there are two clamping grooves, and the clamping grooves are arranged at the upper and lower ends of the front side of the fusion component; the porous structure is filled inside the fusion component, and the bone grafting window is opened in the center of the porous structure.

[0017] Another embodiment provided by the present application is: the fusion component is made of metal or non-metal material, the anti-retreat component is made of metal or non-metal material, and the metal or non-metal material includes titanium alloy, tantalum alloy, cobalt-chromium based alloy and polyetheretherketone.

[0018] Another implementation manner provided by the present application is that the fusion component and the anti-retreat component are integrally formed by using laser powder bed melting technology.

[0019] 3. Beneficial effects

[0020] Compared with the prior art, the bone screw anti-retraction device provided by the present application has the following beneficial effects:

[0021] The bone screw anti-retraction device provided in the present application belongs to the field of additively manufactured medical implants, and specifically relates to an assembly-free screw anti-retraction device for a self-fixating fusion device, which can reduce the steps of separately manufacturing and assembling a structure to prevent screw withdrawal, save costs, and facilitate surgical operations.

[0022] Compared with the anti-retraction structure used in the existing self-fixating intervertebral fusion device, the bone screw anti-retraction device provided by the present application does not require a separate anti-retraction component to be processed, and also reduces the assembly steps between the anti-retraction component and the fusion component, thereby saving costs.

[0023] The bone screw anti-retraction device provided by the present application has an anti-retraction component designed with a locking protrusion and an elastic groove, and a first arc groove and a second arc groove matched with the locking protrusion are designed on the fusion component, and an arc boss is used to transition between the first arc groove and the second arc groove. The arc boss and the locking protrusion are interference fit, so that the anti-retraction component has an obvious change in feel when it rotates from the initial position to the working position, which can give the doctor a signal that it has rotated into place during the operation. The right side of the second arc groove along the clockwise direction has a limiting effect, so that the anti-retraction component is difficult to rotate forward after reaching the working position, and the doctor does not need to adjust the position. The arc boss also has a limiting effect, so that the anti-retraction component will not easily rotate, which can effectively prevent the fixing screw from withdrawing, and the presence of the elastic groove can make the anti-retraction component rotate to the initial position under manual operation, which is convenient for the doctor to revise the intervertebral fusion device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a schematic structural diagram of the bone screw anti-retraction device of the present application;

[0025] Figure 2 It is a perspective schematic diagram of the cooperation between the fusion component and the anti-retraction component of the present application;

[0026] Figure 3 It is a top view schematic diagram of the cooperation between the fusion assembly and the locking mechanism of the present application;

[0027] Figure 4 It is a partial schematic diagram of the anti-recoil component of the present application;

[0028] Figure 5 is a schematic diagram of the fusion components of this application;

[0029] Figure 6 It is a schematic diagram of the assembly process of the anti-recoil component and the fusion component of the present application;

[0030] Figure 7 is a schematic diagram of the design gap of this application;

[0031] Figure 8 This is a second structural schematic diagram of the locking mechanism of the present application. DETAILED DESCRIPTION

[0032] Hereinafter, the specific embodiments of the present application will be described in detail with reference to the accompanying drawings. According to these detailed descriptions, those skilled in the art can clearly understand the present application and can implement the present application. Without violating the principles of the present application, the features in the various embodiments can be combined to obtain new implementations, or certain features in certain embodiments can be replaced to obtain other preferred implementations.

[0033] See also Figures 1 to 8 , Figure 1 This is a schematic structural diagram of a bone screw anti-retraction device according to Example 1 of the present application; Figure 2 A perspective view of the fusion component and the anti-retraction component of the present application; Figure 3 (a) is a top view of the fusion assembly and the locking mechanism of the present application; Figure 3 (b) in Figure 3 (a) Left view of AA cross section; Figure 3 (c) in Figure 3 (b) Left view of BB cross section; Figure 4 (a) is a rear view of the locking mechanism of the present application; Figure 4 (b) is a front view of the locking mechanism of the present application; Figure 5 It is a left view and a partial enlarged view of the cross section of the fusion component AA of the present application; Figure 6 This is a schematic diagram of the working principle of this application; Figure 6(a) is a schematic diagram of the overall structure of the fusion device when the anti-retraction component of the present application is in the initial position; Figure 6 (b) is a left view and a partial enlarged view of the AA cross section of the fusion component and the anti-recoil component when the anti-recoil component of the present application is in the initial position; Figure 6 (c) is a left view and a partial enlarged view of the AA cross section of the fusion component and the anti-recoil component when the anti-recoil component of the present application rotates α / 2°; Figure 6 (d) is a schematic diagram of the overall structure of the fusion device when the anti-retraction component of the present application is in the working position; Figure 6 (e) is a left view and a partial enlarged view of the AA cross section of the fusion component and the anti-recoil component when the anti-recoil component of the present application is in the working position; Figure 7 This is a schematic diagram of the design gap for this application; Figure 8 This is a rear view of the locking mechanism of this application.

[0034] The present application provides a bone screw anti-retraction device, including a fusion component 1, on which a plurality of screw channels 113 are arranged. The fusion component 1 is integrally formed with an anti-retraction component 2, and the anti-retraction component 2 is arranged between the screw channels 113. The anti-retraction component 2 is used to prevent the screws from retreating during the service of the fusion component 1.

[0035] The function of the fusion component 1 is to replace the intervertebral disc to expand the intervertebral space, the fixing screw 3 passes through the screw channel 113 to fix the fusion component 1 between the upper and lower vertebrae, and the function of the anti-retraction component 2 is to prevent the fixing screw 3 from retreating during the service of the fusion component 1 and causing complications.

[0036] Two diagonally located and obliquely penetrating fixing screw channels 113 are respectively designed on the front side of the fusion component 1 , and the fixing screws 3 are reversely fixed in the two fixing screw channels 113 .

[0037] The anti-retraction component 2 and the fusion component 1 are integrally formed. Compared with the existing self-fixating intervertebral fusion device, the present application does not require additional processing of the anti-retraction component 2, thereby reducing the assembly steps between the anti-retraction component 2 and the fusion component 1 and saving costs.

[0038] Furthermore, the anti-retraction assembly 2 includes a baffle 21, a rotating shaft 22 and a locking mechanism 23 which are connected in sequence. The baffle 21 is used to shield the fixing screw 3, the rotating shaft 22 is used to connect the baffle 21 and the locking mechanism 23, and the locking mechanism 23 is used to lock the anti-retraction assembly 2 so that the anti-retraction assembly 2 does not rotate without manual intervention. When renovation is required, the torque can be actively increased to generate rotation to allow the screw to be removed.

[0039] Furthermore, a stepped hole 112 is provided on the fusion component 1 , there are two screw channels 113 , the stepped hole 112 is provided between the two screw channels 113 , the rotating shaft 22 is provided in the stepped hole 112 , and the locking mechanism 23 is provided in the stepped hole 112 .

[0040] Furthermore, the locking mechanism 23 is provided with a plurality of elastic grooves 232 , and a plurality of latching protrusions 231 are provided on both sides of the locking mechanism 23 . The elastic grooves 232 are deformed so that the latching protrusions 231 can be engaged with the arc grooves, and the plurality of arc grooves are provided on the stepped holes 112 .

[0041] A groove 111 is designed at the center of the front side of the fusion component 1, and a stepped hole 112 is designed at the center of the groove 111. The stepped hole 112 is composed of a small hole coaxially matched with the rotating shaft 22 and a large hole coaxially matched with the main part of the locking mechanism 23, starting from the bottom of the groove 111. The bottom of the baffle 21 is parallel to the bottom of the groove 111, and the top of the baffle 21 is parallel to the front side of the fusion component 1.

[0042] The main body of the locking mechanism 23 is in the shape of an oblate cylinder, and the diameter of the main body of the locking mechanism 23 is larger than the rotating shaft 22 , which can ensure that the anti-retraction component 2 itself does not withdraw from the fusion component 1 .

[0043] One or more latching protrusions 231 are arranged on the periphery of the main body of the locking mechanism 23, and the arrangement of multiple latching protrusions 231 can ensure the availability (safety) of the locking mechanism 23. The shape of the latching protrusion 231 can be semi-elliptical, semi-circular or triangular, with a height greater than 0.1 mm and a width greater than 0.1 mm.

[0044] The main body of the locking mechanism 23 is provided with an elastic groove 232 corresponding to the position of the locking protrusion 231, and the width thereof is greater than 0. The elastic groove 232 can be elastically deformed under the action of an external force.

[0045] The outer periphery of the large hole of the stepped hole 112 is designed with one or more first arc grooves 11221 and second arc grooves 11222 that match the positioning protrusion 231, and the number of the first arc grooves 11221 and the second arc grooves 11222 is the same. The angle between the center of the first arc groove 11221 and the second arc groove 11222 and the center of the large hole is α° (α≤90). The first arc groove 11221 and the second arc groove 11222 are transitioned by an arc boss 11223.

[0046] When the anti-retraction assembly 2 is in the initial position, the locking protrusion 231 is located in the first arc groove 11221; when the anti-retraction assembly 2 is rotated α° (α≤90) and is located in the working position, the locking protrusion 231 is located in the second arc groove 11222. When the anti-retraction assembly 2 is in the working position, the two wings of the baffle 21 cover a part of the nail caps of the fixing screws 3 on both sides. The second arc groove 11222 has a limiting effect along the right side in the clockwise direction, so that the anti-retraction assembly 2 no longer rotates forward after reaching the working position.

[0047] The locking protrusion 231 and the arc boss 11223 are interference fit, and the interference is greater than 0. When the anti-retraction component 2 rotates clockwise by α / 2° (α≤90°) under human action, the elastic groove 232 undergoes elastic deformation, so that the locking protrusion 231 can pass through the arc boss 11223 to reach the working position. After reaching the working position, the elastic groove 232 returns to its original shape, and the arc boss 11223 can ensure that the anti-retraction component 2 does not rotate without human intervention. When there is a need for renovation, the torque can be actively increased to produce rotation.

[0048] In order to realize the integrated manufacturing of the fusion component 1 and the anti-retraction component 2, the gap between the rotating shaft 22 and the small hole, the gap between the main part of the locking mechanism 23 and the large hole, the gap between the bottom of the baffle 21 and the bottom of the groove 111, the gap between the upper end surface of the locking mechanism 23 and the interface between the large hole and the small hole, the gap between the side surface of the baffle 21 and the side surface of the groove 111 when the anti-retraction component 2 is in the initial position, and the gap between the locking protrusion 231 and the first arc groove 11221 when the anti-retraction component 2 is in the initial position are all designed to be greater than 0.

[0049] Furthermore, a countersunk hole 211 is provided on the baffle plate 21, and the position of the anti-retraction component 2 is adjusted through the countersunk hole 211. A countersunk hole 211 is provided in the center of the baffle plate 21 to match a tool for rotating the anti-retraction component 2, and its shape includes but is not limited to a straight line, a triangle, a cross, an inner hexagon or a plum blossom.

[0050] Furthermore, the locking mechanism 23 has a diameter greater than that of the rotating shaft 22 , and one side of the elastic groove 232 along the rotating direction passes through the locking mechanism 23 .

[0051] Furthermore, the fusion component includes a limit block, a clamping groove, a porous structure and a bone grafting window. There are two limit blocks, which are located at the diagonal position of the front side of the fusion component, and their function is to limit the implantation depth of the fusion component and prevent the fusion component from being over-implanted into the intervertebral space. There are two clamping grooves, which are located at the upper and lower ends of the front side of the fusion component, and their function is to facilitate the doctor to use the clamping tool to clamp the fusion component during the operation. The porous structure is filled inside the fusion component, and the porous structure is conducive to the bone integration of the fusion component with the upper and lower vertebrae. The bone grafting window is opened in the center of the porous structure.

[0052] Furthermore, the fusion component 1 is made of metal or non-metal material, and the anti-retraction component 2 is made of metal or non-metal material, and the metal or non-metal material includes titanium alloy, tantalum alloy, cobalt-chromium based alloy and polyetheretherketone.

[0053] Furthermore, the fusion component 1 and the anti-recoil component 2 are integrally formed by using laser powder bed melting technology.

[0054] Embodiment 1:

[0055] like Figure 1 , 2 As shown, this embodiment provides a screw-free anti-retraction assembly for a self-fixing fusion device, wherein the self-fixing fusion device includes a fusion device 1, which is used to replace the intervertebral disc to expand the intervertebral space; a fixing screw 3, which is used to fix the fusion component between the upper and lower vertebrae; and an anti-retraction assembly 2, which is used to prevent the fixing screw from withdrawing during the service of the fusion device and causing complications. The anti-retraction assembly 2 and the fusion assembly 1 are integrally manufactured and formed using laser powder bed melting technology, which can reduce the process of separately processing the anti-retraction assembly 2 and assembling, save manufacturing costs and labor costs, and simplify the doctor's operation during the operation.

[0056] The fusion assembly 1 of this embodiment includes a solid frame 11 and a porous structure 12 filled in the solid frame. The porous units used in the porous structure include but are not limited to sinusoidal units, cubic units, body-centered cubic units, diamond units, rhombic dodecahedron units, and irregular trabecular units. The front side of the solid frame 11 is respectively designed with two diagonally located obliquely penetrating fixing screw channels 113, and the fixing screws 3 are reversely fixed in the two fixing screw channels 113.

[0057] like Figure 1 , 4 As shown, the anti-retraction component 2 includes a baffle 21, which is used to cover the fixing screw 3; a rotating shaft 22, one end of which is connected to the baffle 21; and a locking mechanism 23, which is connected to the other end of the rotating shaft 22 and is used to lock the anti-retraction component 2 so that the anti-retraction component 2 cannot rotate without human intervention.

[0058] like Figure 1 , 2 As shown in Figures 3 and 4, a groove 111 is designed at the center of the front side of the solid frame 11 of the fusion component 1, and a stepped hole 112 is designed at the center of the groove 111. The stepped hole 112 is composed of a small hole 1121 coaxially matched with the rotating shaft 22 and a large hole 1122 coaxially matched with the main part of the locking mechanism 23, starting from the bottom of the groove 111. The bottom of the baffle 21 is parallel to the bottom of the groove 111, and the top of the baffle 21 is parallel to the front side of the solid frame 11 of the fusion component 1.

[0059] like Figure 1 As shown, the main body of the locking mechanism 23 is in the shape of an oblate cylinder, and the diameter of the main body of the locking mechanism 23 is larger than the rotating shaft 22 , which can ensure that the anti-retraction component 2 itself does not withdraw from the fusion component 1 .

[0060] like Figure 4 As shown in (a), the outer periphery of the main body of the locking mechanism 23 of this embodiment is provided with two locking protrusions 231, and the provision of two locking protrusions 231 can improve the usability (safety) of the locking mechanism 23. If one of the locking protrusions 231 fails to work, the other locking protrusion 231 can still ensure that the locking mechanism 23 can achieve its function. The shape of the locking protrusion 231 can be semi-elliptical, semi-circular or triangular, and its height is greater than 0.1 mm and its width is greater than 0.1 mm.

[0061] The main body of the locking mechanism 23 of this embodiment is provided with two elastic grooves 232 corresponding to the positions of the locking protrusions 231, and the widths thereof are both greater than 0. The elastic grooves 232 can be elastically deformed under the action of external force.

[0062] like Figure 4 As shown in (b), a countersunk hole 211 is provided in the center of the baffle plate 21 of this embodiment, and the countersunk hole 211 is in the shape of an inner hexagon and cooperates with a tool for rotating the anti-retraction component.

[0063] like Figure 5 As shown, the outer circumference of the large hole 1122 of the stepped hole 112 of this embodiment is designed with two first arc grooves 11221 and two second arc grooves 11222 that match the positioning protrusion 231. The angle between the center of the first arc groove 11221 and the second arc groove 11222 and the center of the large hole 1122 is α° (α≤90). The first arc groove 11221 and the second arc groove 11222 are transitioned by an arc boss 11223.

[0064] like Figure 6 (a) Figure 6 As shown in (b) of FIG. 1 , when the anti-retraction assembly 2 is located at the initial position, the locking protrusion 231 is located in the first arc groove 11221. Figure 6 (d) Figure 6 As shown in (e), when the anti-retraction assembly 2 is in the working position, the locking protrusion 231 is located in the second arc groove 11222. When the anti-retraction assembly 2 is in the working position, the two wings of the baffle 21 cover a part of the nail caps of the fixing screws 3 on both sides, and the second arc groove 11222 has a limiting effect on the right side along the rotation direction, so that the anti-retraction assembly 2 no longer rotates forward after reaching the working position.

[0065] like Figure 6As shown in (c), the locking protrusion 231 and the arc boss 11223 are interference fit, and the interference is greater than 0. When the anti-retraction component 2 rotates α / 2° (α≤90°) under human action, the elastic groove 232 undergoes elastic deformation, so that the locking protrusion 231 can pass through the arc boss 11223 to reach the working position. After reaching the working position, the elastic groove 232 returns to its original shape, and the arc boss 11223 can ensure that the anti-retraction component 2 does not rotate without human intervention. When there is a need for renovation, the torque can be actively increased to produce rotation.

[0066] like Figure 7 As shown, in order to realize the integrated manufacturing of the fusion component 1 and the anti-retraction component 2, the gap between the rotating shaft 22 and the small hole 1121, the gap between the main part of the locking mechanism 23 and the large hole 1122, the gap between the bottom of the baffle 21 and the bottom of the groove 111, the gap between the upper end surface of the locking mechanism 23 and the interface between the large hole 1122 and the small hole 1121, the gap between the side surface of the baffle 21 and the side surface of the groove 111 when the anti-retraction component 2 is in the initial position, and the gap between the locking protrusion 231 and the first arc groove 11221 when the anti-retraction component 2 is in the initial position are all designed to be greater than 0.

[0067] When the anti-recoil component 2 is placed in the initial position, the fusion body 1 and the anti-recoil component 2 are integrally formed and manufactured using laser powder bed melting technology.

[0068] The materials used for the fusion component 1 and the anti-retraction component 2 can be metal or non-metal, including but not limited to titanium alloy, tantalum alloy, cobalt-chromium-based alloy, and polyetheretherketone.

[0069] like Figure 1 As shown, the front side of the solid frame 11 of the fusion assembly 1 of this embodiment is also designed with two limit blocks 114 at diagonal positions, and the upper and lower ends are designed with two clamping grooves 115. A bone grafting window 13 is reserved in the center of the fusion assembly 1.

[0070] Embodiment 2:

[0071] like Figure 8 As shown, in this embodiment, two elastic grooves 232 penetrate the locking mechanism 23 along one side of the rotation direction. The method of manufacturing the bone screw anti-retraction device of the present application is described by Example 3

[0072] Embodiment 3:

[0073] The manufacturing method of the bone screw anti-retraction device of this embodiment comprises the following steps:

[0074] S1: Design the fusion component and the anti-recoil component using 3D design software. First, design the appearance of the fusion component and the anti-recoil component. This embodiment uses laser powder bed melting technology for printing. After testing, the gap between the anti-recoil component and the fusion component is designed to be 0.1mm. The gap includes the gap between the lower end surface of the baffle and the bottom surface of the groove, the gap between the rotating shaft and the stepped hole, the gap between the main part of the locking mechanism and the stepped hole, the gap between the positioning protrusion and the arc groove, and the gap between the side of the baffle and the side of the groove when the anti-recoil component is in the initial position.

[0075] S2: Assemble the designed fusion component and anti-retraction component in the three-dimensional design software, and make the anti-retraction component located at the initial position.

[0076] S3: The material used in manufacturing the bone screw anti-retraction device in this embodiment is TC4. The material properties of TC4 are assigned to the fusion component and the anti-retraction component using finite element analysis software. Finite element analysis shows that the width of the elastic groove is 0.4mm, the height of the locking protrusion is 0.25mm, and the interference fit of the arc boss between the locking protrusion and the arc groove is 0.13mm.

[0077] S4: Export the assembled fusion component and anti-retraction component as a whole as an STL file, and import it into the slicing software. According to the characteristics of laser powder bed fusion technology, if you want to ensure that all gaps are formed and the anti-retraction component can rotate relative to the fusion component, you must choose to tilt the placement method, and the tilt placement angle must be greater than the maximum forming angle of the printing device. The maximum forming angle of the equipment used in this embodiment is 40°, so in this embodiment, the front end face of the fusion component is placed at a 45° angle to the printing platform and an easily removable support is added to the front end face. The model is then sliced ​​with a slice thickness of 20um.

[0078] S5: The sliced ​​layer data after the slicing process in S4 is imported into the printing device, and the anti-recoil component and the fusion component pre-assembled in the three-dimensional design software are manufactured in an integrated manner.

[0079] Although the present application is described above with reference to specific embodiments, it should be understood by those skilled in the art that many modifications may be made to the configurations and details disclosed in the present application within the principles and scope disclosed in the present application. The scope of protection of the present application is determined by the appended claims, and the claims are intended to cover all modifications included in the equivalent literal meaning or scope of the technical features in the claims.

Claims

1. A bone screw anti-retraction device, characterized in that: It comprises a fusion component, on which a plurality of screw channels are arranged, the fusion component and an anti-retraction component are integrally formed, the anti-retraction component is arranged between the screw channels, and the anti-retraction component is used to prevent the screws from retreating during the service of the fusion component.

2. The bone screw anti-retraction device according to claim 1, characterized in that: The anti-retraction assembly comprises a baffle, a rotating shaft and a locking mechanism which are connected in sequence.

3. The bone screw anti-retraction device according to claim 2, characterized in that: The fusion component is provided with a stepped hole, the number of the screw channels is two, the stepped hole is provided between the two screw channels, the rotation axis is provided in the stepped hole, and the locking mechanism is provided in the stepped hole.

4. The bone screw anti-retraction device according to claim 3, characterized in that: The locking mechanism is provided with a plurality of elastic grooves, and a plurality of latching protrusions are provided on both sides of the locking mechanism. The elastic groove hole is deformed so that the latching protrusions can be engaged with the arc grooves, and the plurality of arc grooves are provided on the stepped holes.

5. The bone screw anti-retraction device according to claim 4, characterized in that: The baffle is provided with a countersunk hole, through which the position of the anti-retraction component is adjusted.

6. The bone screw anti-retraction device according to claim 5, characterized in that: The locking mechanism has a diameter greater than that of the rotating shaft, and the elastic groove is in an arc shape.

7. The bone screw anti-retraction device according to claim 6, characterized in that: The locking protrusion is semi-elliptical, semi-circular or triangular; the countersunk hole is straight, triangular, cross, hexagonal or plum blossom.

8. The bone screw anti-retraction device according to claim 6, characterized in that: The fusion component includes a limit block, a clamping groove, a porous structure and a bone grafting window; there are two limit blocks, which are arranged at the diagonal position of the front side of the fusion component, there are two clamping grooves, which are arranged at the upper and lower ends of the front side of the fusion component, the porous structure is filled inside the fusion component, and the bone grafting window is opened in the center of the porous structure.

9. The bone screw anti-retraction device according to claim 5, characterized in that: The fusion component is made of metal or non-metal material, and the anti-retraction component is made of metal or non-metal material. The metal or non-metal material includes titanium alloy, tantalum alloy, cobalt-chromium based alloy and polyetheretherketone.

10. The bone screw anti-retraction device according to any one of claims 1 to 9, characterized in that: The fusion component and the anti-retraction component are integrally formed by using laser powder bed melting technology.

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