阅读说明：本技术 一种椎弓根螺钉及脊柱微创内固定系统 (Vertebral pedicle screw and vertebral column minimally invasive internal fixation system ) 是由 冯兰瑞 崔克玲 于 2021-08-20 设计创作，主要内容包括：本发明提供了一种椎弓根螺钉及脊柱微创内固定系统,该椎弓根螺钉包括钉座和延长组件；钉座包括第一连接片；第一连接片外壁设置有连接凹槽,连接凹槽具有防退结构；延长组件包括第二连接片；第二连接片内壁设置有连接凸起；第一连接片与第二连接片通过连接凹槽与连接凸起的旋转滑动配合连接,防退结构能够防止连接凸起从连接凹槽中退出。该椎弓根螺钉及脊柱微创内固定系统中延长组件与钉座的连接简便且牢固,能够避免现有微创手术时延长组件与椎弓根螺钉钉尾连接强度不足而导致提拉复位操作的失败问题。(The invention provides a pedicle screw and a minimally invasive spine internal fixation system, wherein the pedicle screw comprises a screw seat and an extension component; the nail seat comprises a first connecting sheet; the outer wall of the first connecting sheet is provided with a connecting groove, and the connecting groove is provided with an anti-retreat structure; the extension assembly comprises a second connecting piece; the inner wall of the second connecting sheet is provided with a connecting bulge; the first connecting piece and the second connecting piece are connected with the connecting protrusion in a rotating sliding fit mode through the connecting groove, and the anti-withdrawing structure can prevent the connecting protrusion from withdrawing from the connecting groove. The pedicle screw and the extension component in the spinal minimally invasive internal fixation system are simply and firmly connected with the screw seat, and the problem that lifting and resetting operation fails due to insufficient connection strength of the extension component and the pedicle screw tail in the existing minimally invasive surgery can be solved.)

1. A pedicle screw, comprising a screw seat and an extension assembly;

the nail seat comprises a first connecting sheet; the outer wall of the first connecting sheet is provided with a connecting groove, and the connecting groove is provided with an anti-retreat structure;

the extension assembly comprises a second connecting piece; the inner wall of the second connecting sheet is provided with a connecting bulge;

the first connecting piece and the second connecting piece are connected with the connecting protrusion in a rotating sliding fit mode through the connecting groove, and the anti-withdrawing structure can prevent the connecting protrusion from withdrawing from the connecting groove.

2. The pedicle screw according to claim 1, wherein the connection groove having the anti-back structure is a T-shaped groove structure, a tapered groove structure or a trapezoidal groove structure.

3. The pedicle screw according to claim 1 or 2, wherein the first connecting piece is provided with an anti-retreat groove on the outer wall, the second connecting piece is provided with a connecting hole, the elastic piece is connected with the second connecting piece and positioned in the connecting hole, the inner wall of the elastic piece is provided with an anti-retreat bulge, and the anti-retreat bulge is positioned in the anti-retreat groove after the connecting bulge is in rotating sliding fit with the connecting groove; or the like, or, alternatively,

the anti-moving groove is formed in the outer wall of the first connecting piece, the anti-moving protrusion is arranged on the inner wall of the second connecting piece, and the anti-moving protrusion is located in the anti-moving groove after the connecting protrusion is in rotating sliding fit with the connecting groove.

4. The pedicle screw according to any one of claims 1-3, wherein the inner wall of the second connecting piece is provided with a retaining structure cooperating with the end of the first connecting piece.

5. The pedicle screw according to any one of claims 1 to 4, wherein the anti-slip feature comprises an anti-slip recess, the first tab end having a chamfered feature, the first tab end being disposed in the anti-slip recess.

6. The pedicle screw according to any one of claims 1-5, wherein the screw holder further comprises a screw holder body, the first connecting plate is connected with the screw holder body, and a breaking groove is arranged between the first connecting plate and the screw holder body.

7. Pedicle screw according to one of the claims 1-6, wherein the extension member further comprises a third connection piece connected to the second connection piece, the third connection piece being provided with a pull-up reduction structure;

preferably, the material of the extension assembly is an elastic polymer material or a metal material with elasticity.

8. Pedicle screw according to one of claims 1-7, wherein the width of the third connecting piece is smaller than the width of the second connecting piece.

9. The pedicle screw according to any one of claims 1-8, further comprising a screw body, wherein the screw body comprises a first section, a second section and a third section which are connected in sequence, and the third section is provided with a screw tip; the bottom diameters of the second section are the same, and the bottom diameter of the first section and the bottom diameter of the third section are independently designed in a conical shape; the outer diameter of the nail body is designed to be taper except the nail tip, and the outer diameters of the rest parts are the same.

10. A minimally invasive spinal internal fixation system comprising the pedicle screw of any one of claims 1-9.

Technical Field

The invention relates to the field of medical instruments, in particular to a pedicle screw and a spine minimally invasive internal fixation system.

Background

When a vertebral pedicle screw is adopted for minimally invasive surgery, an extension component in the prior art or made of alloy integrally arranged with the vertebral pedicle screw leads to cost increase, rod penetrating effect is poor, and CT perspective is easy to shield; the extension subassembly that adopts macromolecular material or metal material to make among the prior art installs on the nail tail of pedicle of vertebral arch screw, but the installation is inconvenient in the operation, and the operation is inconvenient, prolongs the time of operation, has increased the potential safety hazard of patient's operation in-process, and its structure can't effectively guarantee the dynamics when carrying out the operation of drawing the reduction in addition, leads to the operation failure.

Disclosure of Invention

The invention overcomes the defects in the prior art, and provides the pedicle screw and the spine minimally invasive internal fixation system, wherein the extension component is simply and firmly connected with the screw seat, the strength requirement of lifting and resetting can be ensured, and the operation time can be saved.

In order to achieve the purpose, the invention adopts the following technical scheme:

one of the objects of the present invention is to provide a pedicle screw comprising a screw seat and an extension assembly;

the nail seat comprises a first connecting sheet; the outer wall of the first connecting sheet is provided with a connecting groove, and the connecting groove is provided with an anti-retreat structure;

the extension assembly comprises a second connecting piece; the inner wall of the second connecting sheet is provided with a connecting bulge;

the first connecting piece and the second connecting piece are connected with the connecting protrusion in a rotating sliding fit mode through the connecting groove, and the anti-withdrawing structure can prevent the connecting protrusion from withdrawing from the connecting groove.

Preferably, the connection groove with the anti-back structure is a T-shaped groove structure, a tapered groove structure or a trapezoidal groove structure.

Preferably, the outer wall of the first connecting piece is provided with an anti-withdrawal groove, the second connecting piece is provided with a connecting hole, the elastic piece is connected with the second connecting piece and is positioned in the connecting hole, the inner wall of the elastic piece is provided with an anti-withdrawal bulge, and the anti-withdrawal bulge is positioned in the anti-withdrawal groove after the connecting bulge is in rotating sliding fit with the connecting groove; or the like, or, alternatively,

the anti-moving groove is formed in the outer wall of the first connecting piece, the anti-moving protrusion is arranged on the inner wall of the second connecting piece, and the anti-moving protrusion is located in the anti-moving groove after the connecting protrusion is in rotating sliding fit with the connecting groove.

Preferably, the inner wall of the second connecting piece is provided with an anti-falling structure matched with the tail end of the first connecting piece.

Preferably, the anti-dropping structure comprises an anti-dropping groove, the end of the first connecting sheet is provided with a chamfer structure, and the end of the first connecting sheet is arranged in the anti-dropping groove.

Preferably, the nail seat further comprises a nail seat body, the first connecting piece is connected with the nail seat body, and a breaking groove is formed between the first connecting piece and the nail seat body.

Preferably, the extension assembly further comprises a third connecting piece connected with the second connecting piece, and the third connecting piece is provided with a lifting reset structure.

Preferably, the material of the extension assembly is an elastic polymer material or a metal material with elasticity.

Preferably, the width of the third connecting piece is smaller than the width of the second connecting piece.

Preferably, the pedicle screw further comprises a screw body, the screw body comprises a first section, a second section and a third section which are sequentially connected, and the third section is provided with a screw tip; the bottom diameters of the second section are the same, and the bottom diameter of the first section and the bottom diameter of the third section are independently designed in a conical shape; the outer diameter of the nail body is designed to be taper except the nail tip, and the outer diameters of the rest parts are the same.

It is another object of the present invention to provide a minimally invasive spinal internal fixation system, which includes the pedicle screw as described above.

Compared with the prior art, the invention has the beneficial effects that:

the pedicle screw and the screw seat in the minimally invasive spinal internal fixation system provided by the invention are simply and firmly connected with the extension component, can meet the strength requirement of lifting and resetting the pedicle screw, and can avoid the problem that the lifting and resetting operation fails due to insufficient connection strength of the extension component and the screw seat in the existing minimally invasive surgery;

the pedicle screw and the minimally invasive spine internal fixation system provided by the invention can avoid mutual interference during internal fixation of the hard caudal pedicle screw, hinder the operation of instruments, avoid the view shielding during operation and carry out contact operation;

the extension component in the pedicle screw and the spine minimally invasive internal fixation system provided by the invention can be made of high polymer materials or metal materials with good elasticity, and can be used for treating related diseases of minimally invasive surgeries with smaller wound incisions when spine internal fixation clinical surgeries such as spine injury, orthopedics and reduction are treated, so that tissue wounds and related complications are reduced;

the pedicle screw and the minimally invasive spine internal fixation system provided by the invention have the advantages that due to the special design of the screw body, the strength of the screw body is high, the screw can be rapidly fed, and the holding force of the screw body is improved.

Drawings

FIG. 1 is an elevation view of a pedicle screw provided in accordance with one embodiment of the invention;

FIG. 2 is a cross-sectional view of a pedicle screw provided in accordance with one embodiment of the invention;

FIG. 3 is a front view of a nail seat and a nail body after being connected according to one embodiment of the invention;

FIG. 4 is a cross-sectional view of the nail seat and the nail body after being connected according to one embodiment of the invention;

FIG. 5 is an elevation view of an extension assembly provided by one embodiment of the present invention;

FIG. 6 is a cross-sectional view of an extension assembly provided in accordance with one embodiment of the present invention;

FIG. 7 is a schematic structural view of an elastic sheet according to an embodiment of the present invention;

FIG. 8 is a cross-sectional view of a staple holder and extension assembly attachment provided by one embodiment of the present invention;

fig. 9 is a schematic perspective view of a portion of an extension assembly according to another embodiment of the present invention.

In the figure:

1 is the nail body, 2 is the gasket, 3 is the nail seat, 4 is the extension subassembly, 5 is connecting groove, 6 is first connecting piece end, 7 is the apex hole, 8 is the bone cement hole, 9 is the third connecting piece, 10 is the second connecting piece, 11 is for carrying the draw hole, 12 is the connecting hole, 13 is first arch, 14 is connecting arch, 15 is the flexure strip, 16 is the anticreep recess, 17 is the anticreep arch, 18 is the anticreep recess, 19 is the fracture groove, 20 is first connecting piece.

Detailed Description

The technical solution of the present invention is further illustrated by the following specific examples.

The invention provides a pedicle screw, which is provided with a screw seat and an extension component, and aims to solve the problems that the connection between the extension component and the screw seat is inconvenient, the connection strength between the extension component and the screw seat is not enough in the lifting process, and the extension component and the screw seat are easy to separate when in lifting reset;

the nail seat comprises a nail seat body and a first connecting sheet connected with the nail seat body; the nail seat body can be any one of the nail seat structures in the prior art, and is generally a U-shaped seat. A breaking groove is arranged between the screw seat body and the first connecting sheet, so that the pedicle screw can be conveniently pulled, lifted and restored, and then the extension assembly is broken. In order to prevent the pedicle screw from interfering with the pedicle of vertebral arch when being driven in, so that the distance between the pedicle screw seat and the vertebral body is smaller and the pedicle screw seat is more firmly fixed, the diameter of the upper part of the screw seat body is larger than that of the lower part, and the difference value of the diameters is 1-3 mm. In addition, the diameter of the upper part of the nail seat body is larger than that of the upper part of the nail body, and the difference value of the diameters is 0.5-1mm, so that the incisional marks can be reduced during the operation.

The first connecting piece and the nail seat body can be of an integrated structure or an assembly structure, and preferably of an integrated structure. Two first connecting sheets are symmetrically connected to the nail seat. Similarly, the extension assembly is provided with two second connecting pieces which are respectively connected with the two first connecting pieces so as to connect the nail seat with the extension assembly.

The connection form of the first connection piece and the second connection is as follows:

the outer wall of the first connecting sheet is provided with a connecting groove, the connecting groove is provided with an anti-withdrawal structure, and the inner wall of the second connecting sheet is provided with a connecting bulge; the connecting bulge rotationally slides into the connecting groove, and the anti-retreating structure can prevent the connecting bulge from being separated from the connecting groove.

After the optimized connecting protrusion is matched with the connecting groove, the inner wall of the second connecting sheet is attached to the outer wall of the first connecting sheet.

Preferably, the connecting groove extends along the width direction of the first connecting piece, i.e. the length of the connecting groove is the same or substantially the same as the width of the first connecting piece;

preferably, the connecting projection extends in the width direction of the second connecting piece, i.e. the length of the connecting projection is the same as, or substantially the same as, the width of the second connecting piece.

The screw seat and the extension assembly are in a rotating sliding fit mode, so that the fit time can be shortened, and the connection structure is provided with the whole connection bulge and the inner wall on one side of the connection groove at the stress part in the lifting and resetting process, so that the anti-lifting strength is remarkably improved, and the problem that the connection strength of the extension assembly and the screw seat is not enough in the lifting and resetting process can be solved.

The preferable structure of the connecting groove is a T-shaped groove structure, a trapezoidal groove structure or a conical groove structure.

In order to further prevent the second connecting sheet from withdrawing from the first connecting sheet, an anti-withdrawal groove is formed in the outer wall of the first connecting sheet, a connecting hole is formed in the second connecting sheet, the elastic sheet is connected with the second connecting sheet and located in the connecting hole, an anti-withdrawal bulge is formed in the inner wall of the elastic sheet, and the anti-withdrawal bulge is located in the anti-withdrawal groove after the connecting bulge is in rotating sliding fit with the connecting groove; or the like, or, alternatively,

the anti-moving groove is formed in the outer wall of the first connecting piece, the anti-moving protrusion is arranged on the inner wall of the second connecting piece, and the anti-moving protrusion is located in the anti-moving groove after the connecting protrusion is in rotating sliding fit with the connecting groove.

According to the pedicle screw provided by the invention, when the second connecting sheet and the elastic sheet are made of metal materials, the second connecting sheet can be provided with the connecting hole; when the second connecting sheet is made of elastic high polymer material, the second connecting sheet can be provided with no connecting hole, namely the inner wall of the second connecting sheet is directly provided with the anti-retreat bulge.

In order to prevent the extension assembly from falling off from the nail seat when the expansion and pressurization are carried out, the inner wall of the second connecting sheet is provided with an anti-falling structure matched with the tail end of the first connecting sheet.

The anti-disengaging structure comprises an anti-disengaging groove, a chamfer angle structure is arranged at the tail end of the first connecting piece, and the tail end of the first connecting piece is arranged in the anti-disengaging groove.

In order to meet the requirements of operations such as lifting reduction and distraction, the extension assembly further comprises a third connecting sheet connected with the second connecting sheet, the third connecting sheet is provided with a lifting reduction structure, the lifting reduction structure can be a lifting reduction hole or a lifting reduction bulge, and the lifting reduction structure is a structure commonly used for lifting reduction of pedicle screws, and can be designed by a person skilled in the art according to needs.

The extension component is preferably made of elastic high polymer materials or elastic metal materials, and when the elastic sheet is used for treating spine injury, orthopedic surgery, reduction and other spine internal fixation clinical surgeries, minimally invasive surgery related diseases with smaller wound incisions can be treated, and tissue wounds and related complications are reduced; avoid hard caudal vertebra arcus vertebrae nail internal fixation time mutual interference, hinder the apparatus operation, the field of vision shelters from when avoiding the operation simultaneously, can carry out contact operation.

Preferably, the width of the third connecting piece is smaller than the width of the second connecting piece.

As known to those skilled in the art, the pedicle screw includes not only a nail seat and an extension assembly, but also a nail body for implantation into the pedicle;

the nail body and the nail seat can be of an integral structure or a split structure. The pedicle screw can be a unidirectional pedicle screw or a universal pedicle screw, and if the pedicle screw is the universal pedicle screw, the pedicle screw can be set to be an assembled type and comprises a screw seat, a screw body and a gasket, wherein the screw body is spread out from the screw seat. The gasket is arranged in the nail seat, the bottom of the gasket is provided with the cambered surface, the top of the gasket is provided with the concave surface, the concave surface is used for placing and fixing the connecting rod, the nail body adopts the ball head nail at the moment, the nail head of the ball head nail is matched with the cambered surface ball socket at the bottom of the gasket, and then the universal adjusting function of the pedicle screw is realized. Further, in order to prevent the gasket from shaking in the nail seat, the two sides of the gasket can be provided with shaking-proof holes or shaking-proof grooves, the two sides of the nail seat are provided with center holes, the depth of the center holes is close to the thickness of the side wall of the nail seat, and the setting positions of the center holes correspond to the shaking-proof grooves on the two sides of the gasket. The force is applied to the side wall of the nail seat from the center hole, the side wall of the nail seat is deformed into a bulge, and the bulge extends into the shaking prevention groove, so that the gasket is prevented from shaking in the nail seat. The screw thread of the nail body can be a single thread, and a multi-thread screw thread can also be selected for quick nail feeding, and generally, the single thread and the double thread are commonly used for facilitating processing; the nail body can be a solid nail or a bone cement nail, such as a bone cement nail, when the nail body is the bone cement nail, the nail tail of the nail body is provided with a bone cement groove, and the bone cement groove is beneficial to flowing bone cement into the pedicle of vertebral arch, so that the pedicle of vertebral arch screw is fixed in the pedicle of vertebral arch. In order to feed nails quickly, improve the strength of a nail body and increase the holding force of the nail body, the nail body comprises a first section, a second section and a third section which are connected in sequence, and the third section is provided with a nail tip; the bottom diameters of the second section are the same, and the bottom diameter of the first section and the bottom diameter of the third section are independently designed in a conical shape; the outer diameter of the nail body is designed to be taper except the nail tip, and the outer diameters of the rest parts are the same.

As known to those skilled in the art, the pedicle screw not only includes a screw seat, a screw body and an extension assembly, but also includes a fixer for fixing a connection rod in the screw seat in threaded fit with the screw seat (at this time, the fixer is provided with external threads, and the inner wall of the screw seat is provided with internal threads), and the fixer can be a jackscrew or the like.

The remaining portions of the pedicle screw, except for the extension assembly, may be made of a biocompatible metallic material, such as a titanium alloy or the like.

The use method of the pedicle screw comprises the following steps:

connecting the extension assembly with the nail seat; the body position of the preoperative patient is adjusted, and a 1.5-3.0cm minimally invasive incision is cut; a guide pin is driven in, and then expansion is carried out through a first-stage expansion sleeve, a second-stage expansion sleeve and a third-stage expansion sleeve; implanting a pedicle screw, and driving the pedicle screw into a vertebral body along a guide pin hole by matching of a screw feeder; the extension component is broken off outwards, and the connecting rod penetrates into the nail seat, so that the position of the pedicle screw can be observed conveniently when the extension component is broken off because the extension component is exposed out of the body; carrying out distraction, pressurization or lifting operation on the vertebral body through the pedicle screw according to the requirement; the connecting rod is locked in the nail seat by the upper jackscrew; breaking off the nail tail of the pedicle screw by using a breaker, and taking out the pedicle screw; the incision is sutured.

The invention also provides a minimally invasive spinal internal fixation system, which comprises the pedicle screw.

Specifically, as shown in fig. 1-9, a minimally invasive spinal internal fixation system comprises a pedicle screw, which comprises a screw seat 3, a screw body 1, an extension component 4, a shim 2 and a fixer;

the nail seat 3 comprises a nail seat 3 body and two first connecting pieces 20 which are symmetrically arranged and form an integral structure with the nail seat 3 body, and a breaking groove 19 is arranged between the nail seat 3 body and the first connecting pieces 20;

the nail seat 3 body is a U-shaped seat;

the diameter of the upper part of the nail seat 3 body is larger than that of the lower part, and the difference value of the diameters is 1-3 mm;

the diameter of the upper part of the nail seat 3 body is larger than that of the upper part of the nail body 1, and the difference value of the diameters is 0.5-1 mm;

the extension component 4 comprises a second connecting sheet 10 and a third connecting sheet 9, wherein the second connecting sheet 10 is connected with a first connecting sheet 20; the width of the second connecting sheet 10 is larger than that of the third connecting sheet 9; the length of the third connecting piece 9 is greater than that of the second connecting piece 10; the third connecting sheet 9 is provided with a plurality of lifting holes 11 along the length direction;

the connection form of the first connecting piece 20 and the second connecting piece 10 is specifically as follows:

the outer wall of the first connecting sheet 20 is provided with a connecting groove 5, the connecting groove 5 is provided with an anti-withdrawal structure, and the inner wall of the second connecting sheet 10 is provided with a connecting bulge 14; the connecting protrusion 14 slides into the connecting groove 5 in a rotating way, and the anti-back structure can prevent the connecting protrusion 14 from falling out of the connecting groove 5;

preferably, after the connecting protrusion 14 is matched with the connecting groove 5, the inner wall of the second connecting sheet 10 is attached to the outer wall of the first connecting sheet 20;

preferably, the connecting groove extends along the width direction of the first connecting piece, i.e. the length of the connecting groove is the same or substantially the same as the width of the first connecting piece;

preferably, the connecting protrusion extends along the width direction of the second connecting sheet, i.e. the length of the connecting protrusion is the same as, or substantially the same as, the width of the second connecting sheet;

the structure of the connecting groove 5 is a T-shaped groove structure, a trapezoidal groove structure or a tapered groove structure, and in this embodiment, the structure of the connecting groove 5 is a trapezoidal groove structure;

an anti-withdrawal groove 18 is formed in the outer wall of the first connecting piece 20, a connecting hole 12 is formed in the second connecting piece 10, the elastic piece 15 is connected with the second connecting piece 10 and is located in the connecting hole 12, an anti-withdrawal protrusion 17 is formed in the inner wall of the elastic piece 15, and the anti-withdrawal protrusion 17 is located in the anti-withdrawal groove 18 after the connecting protrusion 14 is in rotating sliding fit with the connecting groove 5; or the like, or, alternatively,

the outer wall of the first connecting piece 20 is provided with an anti-withdrawal groove 18, the inner wall of the second connecting piece 10 is provided with an anti-withdrawal bulge 17, and the anti-withdrawal bulge 17 is positioned in the anti-withdrawal groove 18 after the connecting bulge 14 is in rotating sliding fit with the connecting groove 5.

According to the pedicle screw provided by the invention, when the second connecting sheet 10 and the elastic sheet 15 are made of metal materials, the second connecting sheet 10 can be provided with the connecting hole 12; when the second connecting piece 10 is made of an elastic polymer material, the second connecting piece 10 may not be provided with the connecting hole 12, that is, the inner wall of the second connecting piece 10 is directly provided with the anti-receding protrusion 17 (at this time, the structure of the connecting piece 10 is shown in fig. 9).

The inner wall of the second connecting piece 10 is provided with an anti-falling structure matched with the tail end 6 of the first connecting piece 20; the anti-dropping structure comprises an anti-dropping groove 16, the tail end 6 of the first connecting piece 20 is provided with a chamfer structure, the tail end 6 of the first connecting piece 20 is arranged in the anti-dropping groove 16, and the anti-dropping groove 16 is formed by a first protrusion 13 arranged on the second connecting piece 10.

The nail body 1 and the nail seat 3 are of a split structure, and the nail body 1 penetrates out of the nail seat 3; the external thread arranged on the nail body 1 is a double-thread; the nail body 1 is a bone cement nail which is of a hollow structure, and a bone cement hole 8 is arranged at a position close to the nail tip; the nail body 1 comprises a first section, a second section and a third section which are connected in sequence, and the third section is provided with a nail tip; the bottom diameters of the second section are the same, and the bottom diameter of the first section and the bottom diameter of the third section are independently designed in a conical shape; the outer diameter of the nail body 1 is designed to be taper except the nail tip, and the outer diameters of the rest parts are the same.

During the nail seat 3 was arranged in to gasket 2, 2 whole saddle types that are of gasket, 2 bottoms of gasket set up the cambered surface, and the top is provided with the concave surface, and the concave surface is used for placing with the fixed connection stick, and the nail body 1 adopts the bulb nail this moment, and the cambered surface ball socket cooperation of its pin fin and 2 bottoms of gasket, and then realize pedicle of vertebral arch screws's universal regulatory function.

Anti-shaking holes or anti-shaking grooves are formed in two sides of the gasket 2, and in the embodiment, anti-shaking holes are formed in two sides of the gasket 2; the nail seat 3 both sides are provided with the apex hole 7, and the thickness that this apex hole 7 degree of depth and nail seat 3 lateral walls is close, and apex hole 7 sets up the groove of rocking prevention that the position corresponds with gasket 2 both sides. The force is applied to the side wall of the nail seat 3 from the center hole 7, the side wall of the nail seat 3 is deformed into a bulge, and the bulge extends into the shaking prevention groove, so that the gasket 2 is prevented from shaking in the nail seat 3.

The fixer is provided with external screw thread, and the nail seat 3 inner wall is provided with the internal thread, preferably negative angle screw thread, and the fixer is the jackscrew or plug screw with the connective bar fixed in nail seat 3.

The operation steps of the spine minimally invasive internal fixator are as follows: connecting the extension assembly 4 with the nail seat 3; the body position of the preoperative patient is adjusted, and a 1.5-3.0cm minimally invasive incision is cut; a guide pin is driven in, and then expansion is carried out through a first-stage expansion sleeve, a second-stage expansion sleeve and a third-stage expansion sleeve; implanting a pedicle screw, and driving the pedicle screw into a vertebral body along a guide pin hole by matching of a screw feeder; the extension component 4 is broken off outwards, and the connecting rod penetrates into the nail seat 3, so that the position of the pedicle screw can be observed conveniently when the extension component 4 is broken off because the extension component 4 is exposed out of the body; carrying out distraction, pressurization or lifting operation on the vertebral body through the pedicle screw according to the requirement; the connecting rod is locked in the nail seat 3 by the upper jackscrew; breaking off the nail tail of the pedicle screw by using a breaker, and taking out the pedicle screw; the incision is sutured.

In this embodiment, the extension member 4 may be made of an elastic polymer material or an elastic metal material, and the rest of the pedicle screw is made of a biocompatible metal material, such as a titanium alloy material.

In conclusion, the pedicle screw and the screw seat 3 and the extension component 4 in the minimally invasive spinal fixation system are simply and firmly connected, so that the strength requirement of lifting and resetting the pedicle screw can be met, and the problem that the lifting and resetting operation fails due to the insufficient connection strength of the extension component 4 and the screw seat 3 in the existing minimally invasive surgery is solved; the hard caudal vertebra pedicle screw can avoid mutual interference when being fixed in the hard caudal vertebra pedicle screw, hinder the operation of instruments, avoid the view shielding during the operation and carry out contact operation; the extension component 4 can be made of high molecular materials or metal materials with good elasticity, and can be used for treating related diseases of minimally invasive surgery with smaller wound incision when spine internal fixation clinical surgeries such as spinal injury, orthopaedics, reduction and the like are treated, so that tissue wound and related complications are reduced; in addition, due to the special design of the screw body, the pedicle screw and the minimally invasive spinal internal fixation system have high strength of the screw body, can be rapidly screwed in, and improve the holding force of the screw body.

Spatially relative terms, such as "upper," "lower," "left," "right," and the like, may be used in the embodiments for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatial terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "lower" can encompass both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Moreover, relational terms such as "first" and "second," and the like, may be used solely to distinguish one element from another element having the same name, without necessarily requiring or implying any actual such relationship or order between such elements.

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.