A pedicle screw with a unidirectional shaft and a side opening

Abstract

The present invention provides a side-opening unidirectional axis pedicle screw, which relates to the field of orthopedic implants, including a screw seat, a screw body and a limit adjustment part; the outer wall of the screw seat is provided with a U-shaped notch, and the inner bottom surface thereof is provided with a mounting hole; the limit adjustment part includes an inner chuck and a buckle, one end of the inner chuck extends into the mounting hole and partially protrudes from the mounting hole, and the other end is embedded in the U-shaped notch, and the embedded part is provided with a clamping hoop type opening structure; the part of the inner chuck protruding from the mounting hole is provided with a cylindrical structure, and the cylindrical structure is provided with a clamping groove extending from its upper end surface to the lower end surface; when the clamping hoop type opening structure is engaged with the outer wall of the steel rod, the buckle is engaged with the clamping groove, the steel rod is clamped, and the freedom of the steel rod along the central axis direction of the screw and along the direction in which the inner chuck extends into the mounting hole is locked. The side-opening unidirectional axis pedicle screw disclosed by the present invention can not only be used for temporary fixation with osteotomy anti-dislocation function, but also has a sagittal plane morphology self-adaptive function.

Description

Technical Field

[0001] The invention relates to the technical field of orthopedic implants, and in particular to a pedicle screw with a side opening and a unidirectional axis. Background Art

[0002] Ankylosing spondylitis (AS) is a chronic inflammatory disease that primarily affects the joints of the spine and pelvis. One of its typical symptoms is the gradual stiffening of the spine and the resulting hunchback, known as ankylosing spondylitis kyphosis. AS kyphosis causes the spine to bend, which affects posture. Patients often have a hunched-over posture, and severe patients may present a "folding knife"-like change. Due to the stiffness and kyphosis of the spine, AS patients have a greatly limited range of motion, making it difficult for them to complete certain daily tasks, such as dressing, going up and down stairs, driving, lifting heavy objects, or doing housework. In addition, the kyphosis of the thoracic spine compresses the chest cavity, causing patients to have difficulty breathing. At the same time, long-term pain, changes in appearance, and limited mobility may lead to psychological problems such as anxiety and depression in patients.

[0003] In the existing osteotomy correction surgery for ankylosing spondylitis kyphosis, doctors mostly use conventional pedicle screws and use titanium rods or cobalt-chromium alloy rods to correct the patient. Conventional pedicle screws usually include a screw seat and a screw body. The screw seat has a U-shaped groove with an upward opening for placing a connecting rod. The U-shaped groove is threaded with a screw plug. After the rod is installed into the U-shaped groove from top to bottom in a vertical direction, it is finally locked with a screw plug in the vertical direction. Before installing the rod, the surgery for ankylosing spondylitis kyphosis generally requires a three-column osteotomy and closed reduction process, that is, after wedge-shaped resection of the target vertebral bone, a kyphosis reduction frame is used to lift the front and rear halves of the patient's trunk with the osteotomized vertebra as the center to achieve reduction. During this reduction process, the proximal and distal ends of the patient's osteotomized vertebra may be dislocated in the vertical direction due to the lack of an implant for temporary fixation, resulting in spinal cord compression behind the vertebra, and paralysis may occur in severe cases. When conventional pedicle screws are used to temporarily fix the proximal and distal ends of the patient's osteotomy vertebra, they cannot be temporarily fixed during the osteotomy reduction process because they use a vertical rod installation method and only have two states: locked and unlocked. In addition, both the locked and unlocked states cannot meet the reduction angle requirements. Therefore, during the osteotomy reduction process, traditional conventional pedicle screws cannot be used for temporary fixation and do not have the function of preventing dislocation.

[0004] Therefore, it is necessary to design a new pedicle screw to solve the problem that the current conventional pedicle screws cannot be temporarily fixed and do not have an anti-dislocation function. Summary of the invention

[0005] The invention aims to provide a lateral opening unidirectional axis pedicle screw which does not require secondary rod installation and has osteotomy anti-dislocation function and sagittal plane morphology self-adaptation function.

[0006] To achieve the above object, the present invention proposes the following technical solution: a lateral opening unidirectional shaft pedicle screw, comprising a screw seat and a screw body fixedly connected from top to bottom, and a limit adjustment part;

[0007] The outer wall of the screw seat is provided with a U-shaped notch with a C-shaped cross section, and the central axis corresponding to the U-shaped notch is perpendicular to the central axis of the unidirectional pedicle screw; the inner bottom surface of the U-shaped notch corresponding to its opening is provided with a mounting hole, and the mounting hole passes through the side wall of the screw seat corresponding to the opening of the U-shaped notch;

[0008] The limit adjustment part includes an inner clamp and a buckle;

[0009] One end of the inner chuck extends into the mounting hole and partially protrudes from the mounting hole, and the other end is embedded in the U-shaped notch, and the part embedded in the U-shaped notch is set as a hoop-type opening structure, the opening direction of the hoop-type opening structure is the same as the opening direction of the U-shaped notch, and the hoop-type opening structure is used to embrace the outer wall of the steel bar along the radial direction of the steel bar, and the encirclement angle of the outer wall of the steel bar is not less than 180°;

[0010] The portion of the inner chuck protruding from the mounting hole is configured as a cylindrical-like structure, and a slot is extended from the upper end surface and the lower end surface of the cylindrical structure, and the buckle is configured as a structure adapted to the shape of the slot; when the clamping opening structure of the inner chuck is engaged with the outer wall of the steel rod, the buckle is engaged in the slot from the outside of the mounting hole, so that the inner wall surface of the U-shaped notch squeezes the clamping opening structure to complete the clamping of the steel rod, locking the freedom of the steel rod along the central axis direction of the unidirectional pedicle screw and along the direction in which the inner chuck extends into the mounting hole.

[0011] Furthermore, the inner chuck is configured as a two-stage step structure consisting of a hoop-type opening structure and a cylindrical-like structure, and the diameter of one end of the hoop-type opening structure close to the cylindrical-like structure is larger than the diameter of the cylindrical-like structure;

[0012] The hoop-type opening structure comprises an upper clamp and a lower clamp, and the upper clamp and the lower clamp are symmetrically arranged from top to bottom along the central axis direction of the unidirectional pedicle screw; a rectangular notch is arranged on the symmetric surface of the upper clamp and the lower clamp, and the rectangular notch extends from the inner bottom surface of the hoop-type opening structure to the inside of the cylindrical structure; the rectangular notch is located at the end surface of the inner bottom surface of the hoop-type opening structure and the openings of the two adjacent end surfaces thereof, and forms a micro-deformation space between the upper clamp and the lower clamp;

[0013] When the buckle is engaged with the slot, the end face of the clamp-type opening structure close to the cylindrical structure side abuts against the end face of the mounting hole, and the upper and lower clamps are squeezed by the inner wall of the U-shaped notch and are deformed in the micro-deformation space and then clamped to the outer wall of the steel rod.

[0014] Furthermore, the card slot is arranged at one end of the cylindrical structure close to the hoop-type opening structure;

[0015] The slot is configured as a semi-enclosed symmetrical slot body, and the semi-enclosed symmetrical slot body is configured to extend from the upper end surface of the outer wall of the quasi-cylindrical structure to the lower end surfaces on both sides of the circumference of the quasi-cylindrical structure, and the two extended ends of the semi-enclosed symmetrical slot body extend to the lower end surface of the quasi-cylindrical structure after crossing the rectangular notch;

[0016] The direction in which the quasi-cylindrical structure extends into the mounting hole is defined as the length direction, and the length of the semi-enclosed symmetrical trough along the length direction gradually shortens from the upper end surface to the lower end surface of the outer wall of the quasi-cylindrical structure;

[0017] The buckle is configured as an inverted U-shaped structure, and the two side arms of the inverted U-shaped structure are adapted to the partial groove shape of the slot on the symmetrical side wall of the cylindrical structure. The length of any side arm of the inverted U-shaped structure along the length direction of the cylindrical structure gradually shortens from the upper end surface to the lower end surface of the outer wall of the cylindrical structure.

[0018] Furthermore, a portion of the bottom surface of the trough body after the two extended ends of the semi-enclosed symmetrical trough body pass through the rectangular notch is provided with a plurality of first limiting steps, and the plurality of first limiting steps are arranged in parallel at equal intervals along the length direction of the cylindrical structure;

[0019] A plurality of second limiting steps are arranged on both side arms of the inverted U-shaped structure at positions corresponding to the positions cooperating with the first limiting steps, and the second limiting steps are adapted to be engaged with the first limiting steps.

[0020] Furthermore, a limiting protrusion is provided on the upper end surface of the cylindrical structure close to the hoop-type opening structure, and the limiting protrusion is located on the symmetry axis of the semi-enclosed symmetrical groove body;

[0021] A limiting slot is provided on the mounting hole on the nail seat, which is recessed toward the inside of the upper edge of the mounting hole away from the U-shaped notch. When the inner clamp is inserted into the mounting hole, the limiting protrusion is engaged in the limiting slot, so that the inner clamp has a micro-rotational freedom in the mounting hole.

[0022] Furthermore, the unilateral rotation angle of the inner chuck in the mounting hole does not exceed 30°.

[0023] Furthermore, the side surfaces of the upper clamping piece and the lower clamping piece that are away from each other and the side surfaces that are close to each other are both configured as arc-shaped surfaces.

[0024] Furthermore, the nail seat and the nail body are integrally formed.

[0025] Furthermore, a positioning slot is symmetrically provided on an outer wall of one end of the screw seat away from the screw body, and an extending direction of the positioning slot is perpendicular to the axial direction of the side-opening unidirectional shaft pedicle screw.

[0026] Furthermore, at least two of the one-way pedicle screws are fastened and connected to the steel rod.

[0027] It can be seen from the above technical solutions that the technical solutions of the present invention have the following beneficial effects:

[0028] The side-opening unidirectional axis pedicle screw disclosed in the present invention comprises a screw seat, a screw body and a limit adjustment part which are fixedly connected from top to bottom; wherein a U-shaped notch is provided through the outer wall of the screw seat, the central axis corresponding to the U-shaped notch is perpendicular to the central axis of the screw, and a mounting hole is provided on the inner bottom surface corresponding to the opening of the U-shaped notch, and the mounting hole passes through the side wall corresponding to the opening of the screw seat and the U-shaped notch; the limit adjustment part comprises an inner clamp and a buckle; one end of the inner clamp extends into the mounting hole and partially protrudes from the mounting hole, and the other end is embedded in the U-shaped notch, and the part embedded in the U-shaped notch is set as a clamp-type opening The structure is characterized in that the opening direction of the hoop-type opening structure is the same as the opening direction of the U-shaped notch, and is used to radially embrace the outer wall of the steel rod, and the encircling angle is not less than 180°; the portion of the inner chuck protruding from the mounting hole is set as a quasi-cylindrical structure, and the quasi-cylindrical structure is provided with a slot extending from its upper end surface to the lower end surface, and the buckle is set as a structure adapted to the shape of the slot; when the hoop-type opening structure of the inner chuck is embraced on the outer wall of the steel rod, the buckle is engaged in the slot from the outside of the mounting hole, so that the hoop-type opening structure completes the steel rod embracing, and locks the freedom of the steel rod along the central axis direction of the screw and along the direction in which the inner chuck extends into the mounting hole. The present invention effectively solves the problem that the current conventional pedicle screws cannot be temporarily fixed and do not have an anti-dislocation function.

[0029] The side-opening unidirectional axis pedicle screw disclosed in the present invention, on the one hand, is based on a structure in which the screw seat is set as a side opening, so that the steel rod is directly installed when the screw is used, and there is no need for secondary installation of the rod; on the other hand, based on the inner clamp hoop-type opening structure and the structural mounting hole design of the screw seat, the buckle and the slot can not only limit the movement of the steel rod in the vertical direction but also lock the freedom of the inner clamp to extend into the mounting hole, and can be used for temporary fixation during surgery to achieve the osteotomy anti-dislocation function, and at the same time has the sagittal plane morphology adaptive function, and is directly locked after the osteotomy closure is completed.

[0030] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, may be considered to be part of the inventive subject matter of the present disclosure, provided such concepts are not mutually inconsistent.

[0031] The foregoing and other aspects, embodiments and features of the present invention can be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as the features and / or beneficial effects of the exemplary embodiments, will be apparent from the following description or learned from the practice of the specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings, in which:

[0033] Figure 1 This is a diagram showing the effect of using the lateral opening unidirectional shaft pedicle screw of the present invention;

[0034] Fig. 2 (a) is a left view of the main body of the pedicle screw with a unidirectional shaft having a side opening of the present invention;

[0035] FIG2( b ) is a front view of the main body of the pedicle screw with a side opening and a unidirectional shaft according to the present invention;

[0036] Fig. 2(c) is a rear view of the main body of the pedicle screw with a side opening and a unidirectional shaft according to the present invention;

[0037] Fig. 3 (a) is a left view of the pedicle screw with a side opening and a unidirectional shaft according to the present invention;

[0038] FIG3( b ) is a front view of a pedicle screw with a side opening and a unidirectional shaft according to the present invention;

[0039] FIG3( c ) is a rear view of the pedicle screw with a side opening and a unidirectional shaft according to the present invention;

[0040] FIG4( a ) is a left side view of the inner chuck in the limit adjustment part of the present invention;

[0041] FIG4( b ) is a front view of the inner chuck in the limit adjustment part of the present invention;

[0042] FIG4( c ) is a rear view of the inner chuck in the limit adjustment part of the present invention;

[0043] FIG5( a ) is a left side view of the buckle in the limit adjustment part of the present invention;

[0044] FIG5( b ) is a front view of the buckle in the limit adjustment part of the present invention;

[0045] FIG. 5( c ) is a rear view of the buckle in the limit adjustment portion of the present invention.

[0046] In the figure, the specific meaning of each mark is as follows:

[0047] 1-nail seat, 1.1-U-shaped notch, 1.2-mounting hole, 1.3-positioning slot; 2-nail body, 3-limit adjustment part, 3.1-inner clamp, 3.2-buckle, 3.3-upper clamp, 3.4-lower clamp, 3.5-rectangular notch, 3.6-slot, 3.7-first limit step, 3.8-second limit step, 3.9-limit protrusion, 3.10-limit slot; 4-steel rod. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meaning understood by people with general skills in the field to which the present invention belongs.

[0049] The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "a", "an" or "the" and other similar words do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" cover the features, wholes, steps, operations, elements and / or components listed after "include" or "comprise", and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0050] Based on the fact that the pedicle screws used in osteotomy and correction surgery are mostly of the upper opening type, the upper opening pedicle screws are used to solve the problem that the proximal and distal ends of the osteotomy vertebra of the patient may be dislocated in the vertical direction due to the lack of temporary fixation of implants, which may cause the proximal and distal ends of the osteotomy vertebra to be dislocated in the vertical direction, causing the patient to be paralyzed. Therefore, the present invention aims to propose a side-opening unidirectional axis pedicle screw, which can be used for temporary fixation during surgery, limit the movement of adjacent screws and vertebral bodies in the ventral and dorsal directions of the patient during surgery, and do not limit the movement of the screws in the front and back directions of the patient's head and feet, effectively avoiding the vertical dislocation of the osteotomy vertebra and reducing the risk of paralysis of the patient. At the same time, the screw buckle has a certain degree of rotational freedom before locking, which can adapt to the sagittal morphological changes of the local osteotomy area from posterior convexity to anterior convexity after osteotomy, so that the fixation rod does not need to be disassembled and assembled again.

[0051] The lateral opening unidirectional shaft pedicle screw disclosed in the present invention will be further specifically introduced below in conjunction with the specific embodiments shown in the accompanying drawings.

[0052] Combination Figure 1 , Figure 2(a) to Figure 2(c) , Figure 3(a) to Figure 3(c) As shown, the side-opening unidirectional axis pedicle screw disclosed in the embodiment comprises a screw seat 1, a screw body 2, and a limit adjustment portion 3 fixedly connected from top to bottom. When the screw is formed, the screw seat 1 and the screw body 2 are integrally formed, and as shown in FIG. Figure 1 When used, at least two of the one-way axis pedicle screws are fixedly connected to the same steel rod 4; wherein the screw seat 1 and the screw body 2 constitute the main body of the one-way axis pedicle screw with a side opening; the outer wall of the screw seat 1 is penetrated by a U-shaped notch 1.1 with a C-shaped cross-section, and the central axis corresponding to the U-shaped notch 1.1 is perpendicular to the central axis of the one-way axis pedicle screw; the inner bottom surface of the U-shaped notch 1.1 corresponding to its opening is provided with a mounting hole 1.2, and the mounting hole 1.2 penetrates the side wall of the screw seat 1 corresponding to the opening of the U-shaped notch 1.1;

[0053] Combination Figure 3(a) to Figure 3(c)As shown, the limit adjustment part 3 includes an inner clamp 3.1 and a buckle 3.2; wherein, one end of the inner clamp 3.1 extends into the mounting hole 1.2 and partially protrudes from the mounting hole 1.2, and the other end is embedded in the U-shaped notch 1.1, and the part embedded in the U-shaped notch 1.1 is set as a hoop-type opening structure, the opening direction of the hoop-type opening structure is the same as the opening direction of the U-shaped notch 1.1, and the hoop-type opening structure is used to radially embrace the outer wall of the steel rod 4, and the surrounding angle of the outer wall of the steel rod 4 is not less than 180°; the inner clamp 3.1 protrudes from the mounting hole 1. 2 is configured as a cylindrical structure, and a slot 3.6 is extended from the upper end surface to the lower end surface of the cylindrical structure, and the buckle 3.2 is configured as a structure adapted to the shape of the slot 3.6; when the clamping opening structure of the inner chuck 3.1 is engaged with the outer wall of the steel rod 4, the buckle 3.2 is engaged in the slot 3.6 from the outside of the mounting hole 1.2, so that the inner wall surface of the U-shaped notch 1.1 squeezes the clamping opening structure to complete the clamping of the steel rod 4, locking the freedom of the steel rod 4 along the central axis direction of the unidirectional axis pedicle screw and along the direction in which the inner chuck 3.1 extends into the mounting hole 1.2.

[0054] Therefore, when the side-opening unidirectional axial pedicle screw of this embodiment is used in osteotomy correction surgery, since the screw seat 1 is designed to be side-opening and the steel rod 4 is clamped and fixed by the clamp-type opening structure, the vertical direction is limited and locked, so it can be used for temporary fixation of the steel rod 4 to avoid vertical dislocation of the proximal and distal ends of the patient's osteotomized vertebra.

[0055] As an optional embodiment, the side-opening unidirectional axis pedicle screw includes two screw seats 1 that are arranged side by side and fixedly connected, and the screw body 2 is fixed to one of the screw seats 1. When the steel rod 4 is fixed, it passes through the U-shaped notches 1.1 of the two screw seats 1 in sequence, further improving the supporting effect of the steel rod 4 when it is fixed.

[0056] Combination Figure 4(a) to Figure 4(c)As shown, the inner clamp 3.1 is configured as a two-stage step structure consisting of a hoop-type opening structure and a cylindrical structure, and the diameter of one end of the hoop-type opening structure close to the cylindrical structure is larger than the diameter of the cylindrical structure. As shown in the figure, the hoop-type opening structure includes an upper clamp 3.3 and a lower clamp 3.4, and the upper clamp 3.3 and the lower clamp 3.4 are symmetrically arranged from top to bottom along the central axis direction of the unidirectional pedicle screw; in the embodiment, in order to facilitate the cooperation with the inner wall surface of the U-shaped notch 1.1 and the embracing of the steel rod 4, the side surfaces of the upper clamp 3.3 and the lower clamp 3.4 that are away from each other and the side surfaces that are close to each other are both configured as arc surfaces. A rectangular notch 3.5 is provided on the symmetric surface of the upper clamping piece 3.3 and the lower clamping piece 3.4, and the rectangular notch 3.5 extends from the inner bottom surface of the hoop-type opening structure to the inside of the cylindrical structure; the rectangular notch 3.5 is located at the end surface of the inner bottom surface of the hoop-type opening structure and the openings of the two adjacent end surfaces thereof, and forms a micro-deformation space between the upper clamping piece 3.3 and the lower clamping piece 3.4;

[0057] Therefore, when the side-opening unidirectional axis pedicle screw is working, the buckle 3.2 is engaged with the slot 3.6, the end face of the clamping hoop-type opening structure close to the cylindrical structure side abuts against the end face of the mounting hole 1.2, and the upper clamp 3.3 and the lower clamp 3.4 are squeezed by the inner wall surface of the U-shaped notch 1.1 and are deformed in the micro-deformation space and then clamped to the outer wall of the steel rod 4.

[0058] In the embodiment, in order to increase the friction resistance after the groove 3.6 and the buckle 3.2 are matched, so that the buckle 3.2 and the inner clamp 3.1 fit more stably and achieve sufficient biomechanical strength, a step structure is used between the end surface of the hoop-type opening structure of the inner clamp 3.1 close to the cylindrical structure and the cylindrical structure to gradually reduce the diameter of the connection part. In addition, in order to facilitate the use of the buckle 3.2, a pair of positioning grooves are symmetrically arranged on the side surface of the two side walls of the buckle 3.2 close to the mounting hole 1.2, which is used to facilitate the clamp to clamp and fix when in use.

[0059] Further in combination with Figure 4(a), the slot 3.6 is arranged at one end of the cylindrical structure close to the clamp-type opening structure; and the slot 3.6 is arranged as a semi-enclosed symmetrical slot body, and the semi-enclosed symmetrical slot body is arranged to extend from the upper end surface of the outer wall of the cylindrical structure to the lower end surfaces on both sides of the circumference of the cylindrical structure, and the two extended ends of the semi-enclosed symmetrical slot body extend to the vicinity of the lower end surface of the cylindrical structure after passing over the rectangular notch 3.5; the direction along which the cylindrical structure extends into the mounting hole 1.2 is defined as the length direction, and the length of the semi-enclosed symmetrical slot body along the length direction gradually shortens from the upper end surface of the outer wall of the cylindrical structure to the lower end surface.

[0060] Combination Figures 5(a) to 5(c)As shown, the buckle 3.2 is set to an inverted U-shaped structure, and the two side arms of the inverted U-shaped structure are adapted to the shape of the partial groove body of the slot 3.6 on the symmetrical side wall of the quasi-cylindrical structure, and the length of any side arm of the inverted U-shaped structure along the length direction of the quasi-cylindrical structure is gradually shortened from the upper end face to the lower end face of the outer wall of the quasi-cylindrical structure. In order to improve the matching stability of the slot 3.6 and the buckle 3.2, a plurality of first limiting steps 3.7 are arranged on the bottom surface of the partial groove body after the two extended ends of the semi-enclosed symmetrical groove body pass over the rectangular notch 3.5, and the plurality of first limiting steps 3.7 are arranged in parallel at equal intervals along the length direction of the quasi-cylindrical structure; a plurality of second limiting steps 3.8 are arranged on the two side arms of the inverted U-shaped structure corresponding to the matching position of the first limiting step 3.7, and the second limiting step 3.8 is adapted to engage with the first limiting step 3.7.

[0061] Further in combination with FIG. 4(a), FIG. 4(c) and FIG. 2(c), a limiting protrusion 3.9 is provided on the upper end surface of the cylindrical structure near the side of the hoop-type opening structure, and the limiting protrusion 3.9 is located on the symmetry axis of the semi-enclosed symmetrical groove body; a limiting groove 3.10 is provided on the upper edge of the mounting hole 1.2 on the nail seat 1 away from the U-shaped notch 1.1 and recessed therein, and when the inner clamp 3.1 extends into the mounting hole 1.2, the limiting protrusion 3.9 is engaged in the limiting groove 3.10, so that the inner clamp 3.1 is 1 has a micro-rotational freedom in the mounting hole 1.1, and the micro-rotational freedom enables the inner clamp 3.1 to rotate at a small angle in the mounting hole 1.2 within 30°; the limiting protrusion 3.9 cooperates with the limiting slot 3.10 to enable the inner clamp 3.1 to rotate at a small angle in the mounting hole 1.2, and can have a certain sagittal plane morphology self-adaptive function during operation, and can also limit the inner clamp 3.1 from escaping from the U-shaped notch 1.1 side of the nail seat 1; when the buckle 3.2 is engaged with the slot 3.6, the micro-rotational freedom is also locked synchronously. The sagittal plane self-adaptive function brought by the small-angle rotation can guide the steel rod to conform to the sagittal plane morphology change of the local osteotomy area from posterior convexity to anterior convexity after osteotomy, so that the steel rod does not need to be disassembled and assembled again, and can be directly locked after the osteotomy is completed.

[0062] Further integration Figure 2(a) to Figure 2(c) The outer wall of one end of the screw seat 1 away from the screw body 2 is symmetrically provided with a positioning groove 1.3, and the extension direction of the positioning groove 1.3 is perpendicular to the axial direction of the side-opening unidirectional axis pedicle screw. The positioning groove 1.3 is used to clamp the screw when fixing the side-opening unidirectional axis pedicle screw during surgery.

[0063] The side-opening unidirectional axis pedicle screw disclosed in the above-mentioned embodiments is based on the structure that the screw seat 1 is set as a side opening, the clamp-type opening structure of the inner clamp 3.1 and the mounting hole design of the screw seat 1, and the buckle 3.2 cooperates with the slot 3.6. Not only can the steel rod 4 be directly installed when the screw is used, but also the movement of the steel rod 4 in the vertical direction and the movement of the inner clamp 3.1 in the direction of extending into the mounting hole 1.2 can be locked, so that the side-opening unidirectional axis pedicle screw can be used for temporary fixation to realize the osteotomy anti-dislocation function when used in osteotomy orthopedic surgery, and at the same time has a sagittal plane morphology adaptive effect.

[0064] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A pedicle screw with a side opening and a unidirectional shaft, characterized in that: It includes a nail seat and a nail body fixedly connected from top to bottom, and a limit adjustment part; The outer wall of the screw seat is provided with a U-shaped notch with a C-shaped cross section, and the central axis corresponding to the U-shaped notch is perpendicular to the central axis of the unidirectional pedicle screw; the inner bottom surface of the U-shaped notch corresponding to its opening is provided with a mounting hole, and the mounting hole passes through the side wall of the screw seat corresponding to the opening of the U-shaped notch; The limit adjustment part includes an inner clamp and a buckle; One end of the inner chuck extends into the mounting hole and partially protrudes from the mounting hole, and the other end is embedded in the U-shaped notch, and the part embedded in the U-shaped notch is set as a hoop-type opening structure, the opening direction of the hoop-type opening structure is the same as the opening direction of the U-shaped notch, and the hoop-type opening structure is used to embrace the outer wall of the steel bar along the radial direction of the steel bar, and the encirclement angle of the outer wall of the steel bar is not less than 180°; The portion of the inner chuck protruding from the mounting hole is configured as a cylindrical-like structure, and a slot is extended from the upper end surface and the lower end surface of the cylindrical structure, and the buckle is configured as a structure adapted to the shape of the slot; when the clamping opening structure of the inner chuck is engaged with the outer wall of the steel rod, the buckle is engaged in the slot from the outside of the mounting hole, so that the inner wall surface of the U-shaped notch squeezes the clamping opening structure to complete the clamping of the steel rod, locking the freedom of the steel rod along the central axis direction of the unidirectional pedicle screw and along the direction in which the inner chuck extends into the mounting hole.

2. The lateral opening unidirectional shaft pedicle screw according to claim 1, characterized in that: The inner chuck is configured as a two-stage step structure consisting of a hoop-type opening structure and a cylindrical structure, and the diameter of one end of the hoop-type opening structure close to the cylindrical structure is larger than the diameter of the cylindrical structure; The hoop-type opening structure comprises an upper clamp and a lower clamp, and the upper clamp and the lower clamp are symmetrically arranged from top to bottom along the central axis direction of the unidirectional pedicle screw; a rectangular notch is arranged on the symmetric surface of the upper clamp and the lower clamp, and the rectangular notch extends from the inner bottom surface of the hoop-type opening structure to the inside of the cylindrical structure; the rectangular notch is located at the end surface of the inner bottom surface of the hoop-type opening structure and the openings of the two adjacent end surfaces thereof, and forms a micro-deformation space between the upper clamp and the lower clamp; When the buckle is engaged with the slot, the end face of the clamp-type opening structure close to the cylindrical structure side abuts against the end face of the mounting hole, and the upper and lower clamps are squeezed by the inner wall of the U-shaped notch and are deformed in the micro-deformation space and then clamped to the outer wall of the steel rod.

3. The lateral opening unidirectional shaft pedicle screw according to claim 2, characterized in that: The card slot is arranged at one end of the cylindrical structure close to the hoop-type opening structure; The slot is configured as a semi-enclosed symmetrical slot body, and the semi-enclosed symmetrical slot body is configured to extend from the upper end surface of the outer wall of the quasi-cylindrical structure to the lower end surfaces on both sides of the circumference of the quasi-cylindrical structure, and the two extended ends of the semi-enclosed symmetrical slot body extend to the lower end surface of the quasi-cylindrical structure after crossing the rectangular notch; The direction in which the quasi-cylindrical structure extends into the mounting hole is defined as the length direction, and the length of the semi-enclosed symmetrical trough along the length direction gradually shortens from the upper end surface to the lower end surface of the outer wall of the quasi-cylindrical structure; The buckle is configured as an inverted U-shaped structure, and the two side arms of the inverted U-shaped structure are adapted to the partial groove shape of the slot on the symmetrical side wall of the cylindrical structure. The length of any side arm of the inverted U-shaped structure along the length direction of the cylindrical structure gradually shortens from the upper end surface to the lower end surface of the outer wall of the cylindrical structure.

4. The lateral opening unidirectional shaft pedicle screw according to claim 3, characterized in that: A plurality of first limiting steps are arranged on the bottom surface of the part of the trough body after the two extended ends of the semi-enclosed symmetrical trough body pass over the rectangular notch, and the plurality of first limiting steps are arranged in parallel at equal intervals along the length direction of the cylindrical structure; A plurality of second limiting steps are arranged on both side arms of the inverted U-shaped structure at positions corresponding to the positions cooperating with the first limiting steps, and the second limiting steps are adapted to be engaged with the first limiting steps.

5. The pedicle screw with a side opening and a one-way shaft according to claim 3, characterized in that: The upper end surface of the cylindrical structure close to the hoop-type opening structure is provided with a limiting protrusion, and the limiting protrusion is located on the symmetry axis of the semi-enclosed symmetrical groove body; A limiting slot is provided on the mounting hole on the nail seat, which is recessed toward the inside of the upper edge of the mounting hole away from the U-shaped notch. When the inner clamp is inserted into the mounting hole, the limiting protrusion is engaged in the limiting slot, so that the inner clamp has a micro-rotational freedom in the mounting hole.

6. The lateral opening unidirectional shaft pedicle screw according to claim 5, characterized in that: The single-side rotation angle of the inner clamp in the mounting hole does not exceed 30°.

7. The pedicle screw with a side opening and a unidirectional shaft according to claim 2, characterized in that: The side surfaces of the upper clamping piece and the lower clamping piece that are away from each other and the side surfaces that are close to each other are both arranged as arc surfaces.

8. The lateral opening unidirectional shaft pedicle screw according to claim 1, characterized in that: The nail seat and the nail body are integrally formed.

9. The lateral opening unidirectional shaft pedicle screw according to claim 1, characterized in that: The outer wall of one end of the screw seat away from the screw body is symmetrically provided with positioning slots, and the extending direction of the positioning slots is perpendicular to the axial direction of the pedicle screw with the side opening and the one-way shaft.

10. The pedicle screw with a side opening and a one-way shaft according to claim 1, characterized in that: At least two unidirectional pedicle screws are fastened and connected to the steel rod.

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