Atlantoaxial fixing device based on vertebral plate screw rigid framework

Abstract

The invention provides an atlantoaxial fixing device based on a vertebral plate screw rigid framework, which belongs to the field of medical instruments and comprises a first fixing device, a second fixing device and a fixing rod. During working, the first fixing device is connected with the axis, and the second fixing device is connected with the atlas. The first fixing device is connected with the first end of the fixing rod, and the second fixing device is connected with the second end of the fixing rod. The first fixing device comprises a base and two axis vertebral plate screws which are in rigid connection with the base through threads, the two screws are connected to the middle of the base at an included angle suitable for an axis vertebral plate, and the distance between the two screws is gradually increased from top to bottom; the two vertebral plate screws are both inserted into an axis vertebral plate to form a rigid stable structure, and the rigid stable structure is used for solving the problems that in the prior art, the risk that a central vertebral pedicle screw damages vertebral arteries is high, and in the four-screw two-rod technology in the prior art, the overall rigidity is poor, and the torsion resistance is insufficient. The operation risk is reduced, and meanwhile the stability and the pullout resistance are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an atlantoaxial fixation device based on a rigid lamina screw structure. Background Technology

[0002] The atlantoaxial joint is located at the craniocervical junction. Dislocation of the atlantoaxial joint can cause high cervical spinal cord compression, leading to paralysis or even death. Clinically, it is necessary to relieve the compression and restore spinal cord function through reduction and fixation to achieve atlantoaxial fusion and long-term stability. Fixation of the atlantoaxial joint is the key to maintaining the reduction and fusion of the lateral mass joints.

[0003] Currently, the standard clinical method for atlantoaxial reduction and internal fixation is the four-screw, two-rod technique. This technique involves screwing two screws with caps into the posterior atlas and axis, using the two screws in the axis as the reduction base and the atlantoaxial screws as longer cap screws. The anterior dislocation of the atlas is lifted and reduced by two titanium rods connected between the caps of the axis and atlas. After reduction, the caps are locked to complete the stable connection and fixation.

[0004] However, the traditional four-nail two-rod technique has the following shortcomings: First, although the pedicle screw of the axis has good fixation strength and pull-out resistance, according to the human axis anatomical studies, there is a risk of damage to the spinal cord and vertebral artery when inserting the pedicle screw of the axis.

[0005] Secondly, the lack of rigid connection between the two pivot screws on the left and right sides results in poor overall rigidity and insufficient torsional resistance of the device. Summary of the Invention

[0006] This invention provides an atlantoaxial fixation device based on a rigid lamina screw framework. According to the anatomical characteristics of the axis, it adopts an integrated axis fixation component with a relatively safe lamina screw fixation, which effectively improves the safety of surgery and solves the defects of the existing four-screw two-rod technology in terms of poor overall rigidity and insufficient torsional resistance. It achieves an atlantoaxial fixation device structure based on a rigid lamina screw framework that reduces surgical risks and greatly improves stability and pullout resistance.

[0007] This invention provides an atlantoaxial fixation device based on a rigid lamina screw framework, comprising: The first fixing device is fixed on the pivot cone; The fixing rod, with its first end connected to the first fixing device, The second fixation device is fixed to the atlas and connected to the second end of the fixation rod; during operation, the second fixation device is connected to the atlas. The first fixing device includes: The base is connected to the first end of the fixing rod; There are two axis lamina screws, which are fixedly connected to the middle of the base at intervals. The distance between the two axis lamina screws gradually increases from top to bottom. During operation, both axis lamina screws are inserted into the axis.

[0008] In addition, the atlantoaxial fixation device based on a lamina screw rigid structure according to the present invention may also have the following additional technical features: In some embodiments of the present invention, each axis lamina screw includes: The first end of the axis lamina screw body is used to connect with the axis cone. The screw tail connects to the second end of the body of the axis lamina screw; A self-locking threaded part is provided on the end of the nail, and the self-locking threaded part is screwed to the base.

[0009] In some embodiments of the present invention, the first fixing device further includes: The first clamping element is mounted on the base; The first fastening member is detachably mounted on the first clamping member, and the first end of the fixing rod is inserted between the first fastening member and the first clamping member.

[0010] In some embodiments of the present invention, the second fixing device includes: Atlas pedicle screw, the first end is used to connect to the atlas; The second clamping member is connected to the second end of the atlas pedicle screw, and the second end of the fixing rod is inserted into the second clamping member.

[0011] In some embodiments of the present invention, the atlantoaxial pedicle screw includes: The body of the atlas pedicle screw, the first end of which is used to connect to the atlas; The ball head connects the second end of the atlas pedicle screw body to the second clamping member.

[0012] In some embodiments of the present invention, each screw tail has a groove at one end away from the body of the axis lamina screw, and the groove is used to insert a wrench to lock the axis lamina screw.

[0013] In some embodiments of the present invention, the surface of each nail tail without a self-locking thread is a spherical surface.

[0014] In some embodiments of the present invention, there are two fixing rods, and the first end of each fixing rod is connected to the base; The second end of each fixing rod is connected to the second fixing device, and the two fixing rods are spaced apart.

[0015] In some embodiments of the present invention, the base includes: The transverse plate has two detachable connecting screws for the vertebral lamina. There are two inclined plates, which are respectively connected to the two ends of the horizontal plate. The angle between each inclined plate and the horizontal plate is an obtuse angle. Each inclined plate part is connected to a side plate part at one end away from the horizontal plate part. Each side plate part is provided with a first clamping member. Each side plate part is parallel to the horizontal plate part.

[0016] In some embodiments of the present invention, it further includes: The first through hole, there are at least two first through holes, each of which is opened on the horizontal plate; The inner wall of each first through hole is provided with a connecting thread, and the upper end of each pivot lamina screw is screwed to a connecting thread.

[0017] In summary, this application includes the following beneficial technical effects: By designing the two axis lamina screws with a gradually increasing spacing from top to bottom and both connected to the base, an isosceles trapezoidal structure is formed between the two axis lamina screws, the axis, and the base, thus creating a stable rigid structure and greatly improving the stability and pull-out resistance of the fixation device. During surgery, the two axis lamina screws can be accurately installed on the base root, and the screw insertion site can avoid the anatomical area of ​​the vertebral artery, thereby reducing the risk of atlantoaxial surgery. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A perspective view of the atlantoaxial connection of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0019] Figure 2 A first perspective view of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0020] Figure 3 A second perspective view of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0021] Figure 4A perspective view of the atlantoaxial pedicle screw in an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown.

[0022] Figure 5 The first perspective view schematically illustrates a second fixation component of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention.

[0023] Figure 6 The second perspective view of a second fixation component of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0024] Figure 7 A perspective view of the axis lamina screw in an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0025] Figure 8 A perspective view of the base of an atlantoaxial fixation device based on a lamina screw rigid architecture according to some embodiments of the present invention is shown schematically.

[0026] Figure label: 1. First fixing device; 11. Base; 111. Horizontal plate portion; 112. Inclined plate portion; 113. Side plate portion; 114. First through hole; 115. Connecting thread portion; 12. Axis lamina screw; 121. Axis lamina screw body portion; 122. Screw tail; 123. Self-locking thread portion; 13. First fixing assembly; 131. First clamping member; 132. First fastening member; 133. First clamping groove; 2. Second fixing device; 21 211. Second fixing component; 212. Second clamping component; 214. Washer; 22. Atlas pedicle screw; 221. Atlas pedicle screw body; 222. Ball head; 23. Third fixing component; 231. Third clamping component; 232. Third clamping component; 24. Clamping fixing component; 241. Clamping part; 242. Fourth clamping component; 243. Clamping groove; 3. Fixing rod; 4. Atlas; 5. Pivot. Detailed Implementation

[0027] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0028] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “” used herein may also indicate the inclusion of the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated, unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0029] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0030] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may also be rotated 90 degrees or in other orientations, and the spatial relative descriptors used in the text will be interpreted accordingly.

[0031] In the existing four-screw two-rod technique, the pedicle screw of the axis needs to cross the vertebral artery area, which carries the risk of damaging the vertebral artery. The laminectomy technique generally uses screws with universal tail caps, which have poor fixation rigidity and strength, easily leading to postoperative loss of reduction.

[0032] like Figures 1 to 8As shown, according to an embodiment of the first aspect of the present invention, an atlantoaxial fixation device based on a lamina screw rigid structure is proposed, comprising a first fixation device 1, a second fixation device 2 and a fixation rod 3, wherein a first end of the fixation rod 3 is connected to the first fixation device 1 and a second end of the fixation rod 3 is connected to the second fixation device 2. The first fixing device is fixed to the pivot 5, and the second fixing device is fixed to the atlas 4; The first fixation device 1 includes a base 11 and axis lamina screws 12. The first end of the fixation rod 3 is connected to the base 11. Two axis lamina screws 12 are fixedly connected at intervals in the middle of the base 11. The distance between the two axis lamina screws 12 gradually increases from top to bottom. During operation, the second fixation device 2 is connected to the atlas 4, and the two axis lamina screws 12 are inserted into the axis 5.

[0033] In the above embodiments, it should be noted that "up" and "down" here refer to the directions. Figure 1 The directions marked as up and down are shown in the figure; both ends of the base 11 are connected to the first end of a fixing rod 3 through a U-shaped tail cap.

[0034] By gradually increasing the distance between the two axis lamina screws 12 from top to bottom and connecting them to the base 11, the two axis lamina screws 12 are at a relatively fixed angle, thereby increasing the degree of matching with the shape of the human axis 5, indirectly reducing the technical requirements for the placement of the axis 5, and avoiding the anatomical area of ​​the vertebral artery, thus increasing the safety of the operation.

[0035] The setting of the fixation rod 3 realizes the interconnection between the first fixation device 1 and the second fixation device 2, which can pull the dislocated atlantoaxial vertebra 4 posteriorly to reduce it, and realize the function of atlantoaxial reduction and fixation.

[0036] The technical effects achieved by the above embodiments are as follows: by setting the spacing between the two axis lamina screws 12 to gradually increase from top to bottom and both connected to the base 11, an isosceles trapezoidal structure is formed between the two axis lamina screws 12, the axis 5, and the base 11, thereby forming a stable rigid structure and greatly improving the stability and pull-out resistance of the fixation device; when performing surgery, the two axis lamina screws 12 can accurately install the two pedicle screws on the base root, and the probability of pedicle screw dislocation is low when under force, thereby reducing the risk of atlantoaxial surgery.

[0037] Optional, such as Figure 2 , Figure 3 , Figure 7 and Figure 8As shown, each axis lamina screw 12 includes an axis lamina screw body 121, a screw tail 122, and a self-locking threaded portion 123. The first end of the axis lamina screw body 121 is used to connect with the axis 5, and the second end of the axis lamina screw body 121 is connected with the screw tail 122. The screw tail 122 is provided with a self-locking threaded portion 123, which is screwed to the base 11.

[0038] In the above optional embodiments, it should be noted that the surface shape of the nail tail 122 without the self-locking thread 123 is spherical, the nail tail 122 and the pivot lamina screw body 121 are integrally formed, and the end of the nail tail 122 away from the pivot lamina screw body 121 is provided with an internal hexagonal groove or other form of groove for tightening.

[0039] The advantages of the above optional embodiments are: the self-locking threaded portion 123 enables reliable locking and fixation between the pivot lamina screw 12 and the base 11, effectively improving the stability and pull-out resistance of the device.

[0040] Optional, such as Figures 1 to 3 and Figure 8 As shown, the first fixing device 1 also includes a first clamping member 131 and a first fastening member 132. The first clamping member 131 is mounted on the base 11, and the first fastening member 132 is detachably mounted on the first clamping member 131. The first end of the fixing rod 3 is inserted between the first fastening member 132 and the first clamping member 131.

[0041] In the above optional embodiments, it should be noted that the first fixing device 1 further includes a first clamping groove 133. The bottom of the first clamping member 131 is provided with the first clamping groove 133. The first clamping groove 133 is arc-shaped. The first end of the fixing rod 3 is inserted between the first fastening member 132 and the bottom wall of the first clamping groove 133. The first clamping member 131 is a U-shaped tail cap structure. The second clamping member 132 is a U-shaped tail cap structure.

[0042] The first clamping member 131, the first fastening member 132, and the first clamping groove 133 are combined to form the first fixing component 13.

[0043] The first fastener 132 can be a common bolt structure, preferably a customized bolt structure. The specific structure of the customized bolt structure is as follows: the inner ring is a hexagonal socket, the middle part is a column, and the outer ring of the column is threaded; it can also be a hexagonal threaded sleeve structure.

[0044] The advantages of the above optional embodiments are that the arrangement of the first clamping member 131 and the first fastening member 132 ensures the reliability of the connection between the fixing rod 3 and the first fixing device 1.

[0045] Optional, such as Figures 1 to 6As shown, the second fixation device 2 includes a second clamping member 211 and an atlas pedicle screw 22. The second end of the fixing rod 3 is inserted into the second clamping member 211. The first end of the atlas pedicle screw 22 is used to connect with the atlas 4, and the second end of the atlas pedicle screw 22 is connected to the second clamping member 211.

[0046] In the above optional embodiments, it should be noted that the second fixing device 2 further includes a second fastening member 212. The second fastening member 212 can be a common bolt structure, preferably a customized bolt structure. The customized bolt structure specifically has an inner ring of a hexagonal socket, a central column, and an outer ring of the column with threads; it can also be a hexagonal threaded sleeve structure. The second fastening member 212 is screwed onto the second clamping member 211. The second end of the fixing rod 3 is inserted between the second clamping member 211 and the second fastening member 212. The atlas pedicle screw 22 is self-tapping threaded and inserted onto the atlas 4.

[0047] The advantages of the above optional embodiments are as follows: the setting of the second clamping member 211 and the second fastening member 212 ensures the reliability of the connection between the fixing rod 3 and the second fixing device 2. The atlas pedicle screw 22 and the axis lamina screw 12, combined with the setting of the fixing rod 3, realize the reliable posterior pull-back reduction of the atlas 4, realize the atlantoaxial reduction and fixation function, and ensure the stability and firmness of the connection.

[0048] Optional, such as Figure 4 As shown, the atlas pedicle screw 22 includes a ball head 222 and an atlas pedicle screw body 221. The first end of the atlas pedicle screw body 221 is used to connect with the atlas 4, and the second end of the atlas pedicle screw body 221 is connected to the second clamping member 211 through the ball head 222.

[0049] In the above optional embodiments, it should be noted that the ball head 222 is ball-jointed with the second clamping member 211; and the pedicle screw body 221 of the atlas is screwed with the atlas 4.

[0050] The bottom of the second clamping member 211 is provided with a pad 214. The upper surface of the pad 214 is arc-shaped and the lower surface of the pad 214 is flat. During operation, the upper surface of the pad 214 abuts against the fixing rod 3, and the lower surface of the pad 214 abuts against the top of the ball head 222 to cooperate with the second fastening member 212 to limit the atlas pedicle screw. The second end of the fixing rod 3 is inserted between the second fastening member 212 and the bottom wall of the pad 214.

[0051] The advantages of the above optional embodiments are as follows: the ball head 222 increases the convenience of connecting the atlas pedicle screw 22 and the second clamping member 211, while the angle of the atlas pedicle screw 22 can be appropriately adjusted according to actual needs, thus increasing the convenience of use.

[0052] Optional, such as Figures 1 to 3 , Figure 7 and Figure 8 As shown, there are two fixing rods 3. The first end of each fixing rod 3 is connected to the base 11, and the second end of each fixing rod 3 is connected to the second fixing device 2. The two fixing rods 3 are arranged at intervals.

[0053] In the above optional embodiments, it should be noted that, optionally, the number of the first fastening member 132, the first clamping member 131, the second clamping member 211, the second fastening member 212, and the atlas pedicle screw 22 are all two. Each first clamping member 131 is screwed with a first fastening member 132. The first end of each fixing rod 3 is inserted between a first fastening member 132 and the corresponding first clamping member 131. The second end of each fixing rod 3 is inserted between the second fastening member 212 and the second clamping member 211. Each second clamping member 211 is ball-jointed with an atlas pedicle screw 22.

[0054] The beneficial effect of the above optional embodiments is that by setting two fixing rods 3, a four-nail two-rod structure is formed, which further ensures the effectiveness of the device.

[0055] Optional, such as Figure 8 As shown, the base 11 includes a horizontal plate portion 111, an inclined plate portion 112, and a side plate portion 113. An inclined plate portion 112 is connected to each end of the horizontal plate portion 111. A side plate portion 113 is connected to the end of each inclined plate portion 112 away from the horizontal plate portion 111. A first clamping member 131 is provided on each side plate portion 113. A first fastening member 132 is detachably connected to each first clamping member 131. A fixing rod 3 is inserted between each first clamping member 131 and the corresponding first fastening member 132. Two pivot lamina screws 12 are detachably connected to the horizontal plate portion 111. The angle between each inclined plate portion 112 and the horizontal plate portion 111 is an obtuse angle. Each side plate portion 113 is parallel to the horizontal plate portion 111.

[0056] In the above optional embodiments, it should be noted that the horizontal plate portion 111, the inclined plate portion 112, and the side plate portion 113 are integrally formed or welded together.

[0057] The advantages of the above optional embodiments are: the arrangement of the horizontal plate portion 111, the inclined plate portion 112 and the side plate portion 113 enables the first fixing device 1 to effectively adapt to the shape of the pivot cone 5, thereby increasing the convenience of the operation.

[0058] Optional, such as Figure 2 , Figure 3 , Figure 7 and Figure 8As shown, at least two first through holes 114 are provided on the horizontal plate portion 111, and each first through hole 114 has a connecting thread portion 115 on its inner sidewall. The upper end of each pivot vertebral lamina screw 12 is screwed to a connecting thread portion 115.

[0059] In the above optional embodiments, it should be noted that the self-locking thread 123 of each pivot lamina screw 12 is screwed to a connecting thread 115; the first through hole 114 is an inclined hole.

[0060] The advantages of the above optional embodiments are that the self-locking threaded portion 123 increases the convenience of connecting the pivot lamina screw 12 to the base 11 while also increasing the stability.

[0061] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An atlantoaxial fixation device based on a lamina screw rigid framework, characterized in that, include: The first fixing device (1) is fixed on the pivot (5); The fixing rod (3) has its first end connected to the first fixing device (1). The second fixing device (2) is fixed on the atlas (4) and connected to the second end of the fixing rod (3); during operation, the second fixing device (2) is connected to the atlas (4); The first fixing device (1) includes: Base (11), the base (11) is connected to the first end of the fixing rod (3); There are two pivot lamina screws (12). The two pivot lamina screws (12) are fixedly connected to the middle of the base (11) at intervals. The distance between the two pivot lamina screws (12) gradually increases from top to bottom. During operation, both pivot lamina screws (12) are inserted into the pivot (5).

2. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 1, characterized in that, Each of the aforementioned axis lamina screws (12) includes: The first end of the pivot lamina screw body (121) is used to connect with the pivot (5); The screw tail (122) is connected to the second end of the screw body (121) of the axis vertebral lamina; A self-locking threaded portion (123) is provided on the nail tail (122), and the self-locking threaded portion (123) is screwed to the base (11).

3. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 1, characterized in that, The first fixing device (1) further includes: The first clamping member (131) is mounted on the base (11); The first fastening member (132) is detachably mounted on the first clamping member (131), and the first end of the fixing rod (3) is inserted between the first fastening member (132) and the first clamping member (131).

4. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 1, characterized in that, The second fixing device (2) includes: Atlas pedicle screw (22), the first end of which is used to connect to the atlas (4); The second clamping member (211) is connected to the second end of the atlantoaxial pedicle screw (22), and the second end of the fixing rod (3) is inserted into the second clamping member (211).

5. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 4, characterized in that, The atlantoaxial pedicle screw (22) includes: The first end of the atlas pedicle screw body (221) is used to connect with the atlas (4). The ball head (222) is connected to the second clamping member (211) at the second end of the atlas pedicle screw body (221).

6. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 2, characterized in that, Each of the screw tails (122) has a groove at the end opposite to the body (121) of the axis lamina screw, the groove being used to insert a wrench to lock the axis lamina screw (12).

7. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 6, characterized in that, The surface of each of the said nail tails (122) without the self-locking thread (123) is spherical.

8. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 1, characterized in that, There are two fixing rods (3), and the first end of each fixing rod (3) is connected to the base (11); The second end of each of the fixing rods (3) is connected to the second fixing device (2), and the two fixing rods (3) are spaced apart.

9. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 3, characterized in that, The base (11) includes: The transverse plate (111) has two pivot lamina screws (12) detachably connected to it. There are two inclined plate portions (112), which are respectively connected to the two ends of the horizontal plate portion (111). The angle between each inclined plate portion (112) and the horizontal plate portion (111) is an obtuse angle. Each of the inclined plate portions (112) is connected to a side plate portion (113) at one end away from the horizontal plate portion (111). Each of the side plate portions (113) is provided with a first clamping member (131). Each of the side plate portions (113) is parallel to the horizontal plate portion (111).

10. The atlantoaxial fixation device based on a lamina screw rigid structure according to claim 9, characterized in that, Also includes: There are at least two first through holes (114), and each first through hole (114) is formed on the horizontal plate portion (111); The connecting thread (115) is provided on the inner sidewall of each of the first through holes (114), and the upper end of each pivot lamina screw (12) is screwed to one of the connecting thread (115).

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