KR100645377B1 - Vertebral fixation apparatus having length variable type rod and pedicle screws - Google Patents

Abstract

The present invention is composed of a rod for connecting the pedicle screw screw in the form of segments to be connected continuously to the pedicle screw alternately (交互), but made of a forming memory alloy that is flexibly variable in a predetermined temperature range screw is uniformly The present invention relates to a pedicle fixation device which can freely connect by varying the shape and length of a rod even if it is not stuck and shifts from a desired installation position.

In the first embodiment of the present invention, the receiving groove is formed in the upper portion, the head portion formed with at least one recessed in the axial direction at the bottom of the receiving groove, and the upper and lower sides of the pedicle on the bottom of the head portion Pedicle screw to serve as a fixation of the damaged pedicle by having a screw portion embedded; A rod consisting of a shape memory alloy that is transformed at a predetermined temperature, the rod being mounted on a ditch of the bottom of the receiving groove to connect the pedicle screws to correct the angle and spacing of the pedicle; And it is inserted into the receiving groove of the pedicle screw, characterized in that it comprises a fixing means for pressing to prevent the rod from flowing.

Pedicle, screw, shape memory alloy, rod, coil spring

Description

Vertebral fixation apparatus having length variable type rod and pedicle screws}             

1 is a perspective view showing a coupling configuration of a pedicle fixation device according to the prior art.

Figure 2 is a perspective view showing the installation state of the pedicle screw rod according to the prior art.

Figure 3 is an exemplary view showing various forms of pedicle screw rod according to the prior art.

Figure 4 is an exploded perspective view showing the configuration of a first embodiment of a pedicle fixation device according to the present invention.

5 is a perspective view of the combination of FIG.

6 is a cross-sectional view taken along line A-A of FIG.

Figure 7 is a perspective view showing another embodiment of the rod which is the main part of the present invention.

Figure 8 is a cross-sectional view showing another embodiment configuration of the pedicle screw which is the main part of the present invention.

Figure 9a and Figure 9b is an exploded view and a cross-sectional view showing the configuration of the second embodiment of the pedicle fixation device according to the present invention.

Figure 10 is a plan view schematically showing a continuous installation state of the rod using the two pedicle pedicle screws in the second embodiment of the pedicle fixation device according to the present invention.

* Explanation of symbols for main parts of the drawings

10: rod 11: rod body

12: coil spring 13: waveform

20: pedicle screw 21: head

22: ditch 23: threaded portion

24: rod fitting groove 30: set screw

40: head cap

The present invention relates to a pedicle fixation device for firmly fixing a damaged or deformed pedicle in the corrected state, and more particularly, the rod connecting the pedicle screw screw in the form of a segment, which varies with temperature It relates to a pedicle fixation device that can be manufactured by the shape memory alloy to facilitate the spinal correction procedure.

In general, the spine is usually composed of 24 bones (except sacral bones), which are connected by joint nodes, with discs between each joint. By this configuration, the vertebrae not only support the human posture while buffering, but also serve as the basis for exercise and protect the organs of the internal organs. However, as the spine lasts for a long time due to external anthropogenic factors, degenerative or abnormal posture, when the spine is damaged or twisted, the spine is squeezed by nerves passing through the spinal canal, causing severe pain.

Patients with damaged parts of the spine are unable to perform activities necessary for personal life, and even if the degree of damage is not severe, the damaged parts of the spine are pressed or touched by other adjacent parts, causing pain. Because of this, a pedicle fixation device must be inserted in the damaged or damaged part of the spine so that the damaged part is not pressed or pressed.
Conventional degenerative spinal diseases undergo surgical treatment if they are not effective in conservative treatment. In particular, spinal stenosis, anterior dislocation, and spondylosis with spinal segmental instability are performed by spinal fusion using spinal fixation device. At this time, the conventional technique used has been fixed with a rigid rod (rigid rod) with no movement at all has caused a number of side effects over time after surgery.

As shown in FIG. 1, the pedicle fixation device includes a U-shaped accommodating groove 101a, a head portion 101 having a female thread formed on an inner circumferential surface of the accommodating groove 101a, and inserted into the pedicle. A pedicle screw 100 having a threaded portion 102 and inserted into upper and lower sides of the damaged spine and serving as a fixing stand; A rod 200 connected through each pedicle screw 100 to serve as a pedicle correction; The set screw 300 is fitted into the receiving groove 101a, is fastened to the female thread formed therein to fix the rod 200, and has a wrench insertion groove 300a formed thereon.

The installation state of the pedicle screw and the rod in the pedicle fixation device according to the prior art will be briefly described with reference to FIG.

As shown in the figure, the screw portion 102 of the pedicle screw nail 100 is fixed to each pedicle 500, the rod 200 in the U-shaped receiving groove 101a formed in the head portion 101 Insert and settle down.

In this state, the set screw 300 is aligned with the female thread formed in the receiving groove 101a, and then a hexagon wrench or the like is inserted into the wrench insertion groove formed in the upper portion of the set screw 300 to rotate the set screw 300. The bottom surface presses the outer diameter of the rod 200 so that the rod 200 is fixed in the receiving groove of the pedicle screw 100. That is, the installation state of the rod 200 connecting between the pedicle 500 and the pedicle 500 is maintained firmly.

However, in such a conventional pedicle fixation device, the rod plays the most important role in correcting the spine. Therefore, the influence of the rod material or elasticity on the human body is great after fusion of the pedicle.

Conventional rods are configured in a single form to connect several pedicle screws, and most of them are made of medical titanium material, so there is no elasticity of the rods themselves. Because of this, it is difficult to maintain a normal waist curve after vertebral surgery, after fusion of vertebral nodes in the shape of a single rod. In addition, since the load is concentrated on the upper or lower nodes of the spine of the pedicle screw-embedded area after the rod is fully fused in the shape of the rod, it may cause another spinal canal narrowing or instability within several years after the fusion. Doing.

In particular, when an impact is applied to the waist due to external factors, there is a problem that the rod is broken or buried in the spinal column.

In addition, since the conventional rod is manufactured to be bent like the shape of a general spine irrespective of the shape of the individual spine, it is difficult to standardize each individual product and produce a variety of shapes. It's working. The rod of such a structure causes a lot of trouble even when connecting to the pedicle screw. In other words, the shape of the pedicle is different for each person, it is very difficult to mount the rod if the pedicle screw is not uniformly lodged between the node and the node. This is related to the physical properties of the non-elastic rods. In this case, install the rod after adjusting the angle of the head arbitrarily by using a polyaxial type screw in which the head is freely rotated around the screw part in a predetermined angle range by twisting the screw obliquely to adjust the distance and direction. It will be fixed in position. As such, it is necessary to precisely determine the installation position of the screws and to make a hole in the pedicle so that the precision of the surgery is increased, thereby increasing the burden on the doctor. In addition, to produce a rod of a single shape that fits the pedicle curvature, and uniformly determine the installation position of the screw, there is a problem that the operation time is long because you have to spend a lot of time.

In order to overcome the problems with such rods, rods of various structures having elasticity have been conventionally proposed. As an example, disclosed is an elastic rod for pedicle screw connection of Utility Model Registration No. 0338006. The rod disclosed herein has a structure in which a rod body portion 601 and an elastic connecting portion 603 are formed at an intermediate portion of the rod body portion 601. As shown in FIG. 3, the elastic connecting portion 603 has a circular ring having one side, a coil spring, and a bar shape having a diameter smaller than that of the rod body.

As described above, the structure in which the elastic connection portion is formed in the middle portion of the rod gives the bending deformation of the rod body portion 601 to provide fluidity within a certain range between the pedicle node and the node. However, the above structure causes a problem that the pedicle correction function, which is the original function of the rod, is lost because the elastic range of the elastic connection part is too large. That is, the rod must be firmly supported while connecting between the pedicle node and the node. In the proposed rod structure, the rod body parts are separated from each other, so that the rod body part can move freely within the elastic range of the elastic connection part. Can be. In addition, since the diameter of the elastic connecting portion is formed smaller than the diameter of the rod body portion, there is a problem that the spine holding strength due to spinal correction is weak, so that the pedicle node and the node cannot be firmly fixed.

In addition, the elastic rod structure for pedicle screw connection still has a problem that it is difficult to connect the rod without artificially bending the rod to the arrangement of the pedicle screw when the arrangement of the pedicle screw is misaligned.

Therefore, the present invention has been proposed to solve the above problems, it is possible to increase the fixing force between the spinal segments by fixing the intervertebral segment with a rod provided with an elastic portion, and at the same time can maintain the movement between the spinal segments smoothly The purpose is to provide a pedicle fixation device.
In addition, the present invention is configured to form a rod for connecting the pedicle screw segment in the form of segments to be connected continuously to the pedicle screw alternately (交互), manufactured by a shape memory alloy to flexibly vary each rod at a predetermined temperature range There is another object to provide a pedicle fixation device that can freely connect by varying the shape and length of the rod even if the screws are not uniformly lodged and shifted from the desired installation position.

In addition, the present invention is to form the middle portion of the rod into an elastic section, the elastic section is to maintain the strength enough to the rod to correct the pedicle while exerting an elastic force when the impact is applied to the pedicle Another object is to provide a pedicle fixation device that can impart fluid between nodes.

In order to achieve the above object, in the first embodiment of the present invention, an accommodating groove is formed in an upper portion of the head, and at least one head portion having an axially exploded groove formed at the bottom of the accommodating groove, Pedicle screw to serve as a fixed pedicle of the damaged pedicle having a screw portion embedded in the upper and lower sides; A rod consisting of a shape memory alloy that is transformed at a predetermined temperature, the rod being mounted on a ditch of the bottom of the receiving groove to connect the pedicle screws to correct the angle and spacing of the pedicle; And it is inserted into the receiving groove of the pedicle screw, characterized in that it comprises a fixing means for pressing to prevent the rod from flowing.

According to a second embodiment of the present invention, a pedicle screw serving as a fixing stand for a damaged pedicle is provided with a head portion having at least one first groove formed thereon and a screw portion embedded in the upper and lower sides of the pedicle at the bottom of the head portion; A rod consisting of a shape memory alloy which is transformed at a predetermined temperature, and seated in the first groove of the head to connect the pedicle screws, and to correct the angle and spacing of the pedicle; A head cap positioned above the head part and having a second groove formed at a bottom surface corresponding to the first groove of the head part; And fixing means for fixing the head cap and the pedicle screw, and pressing the rod located between the first and second grooves to prevent the rod from flowing.

In the first and second embodiments of the present invention, the head portion of the pedicle screw is characterized in that it further comprises a rod fitting groove for fixing the end of the rod. This is to ensure that the rod is firmly fixed to the pedicle screw when the morphological rod is restored.

In addition, in the case of forming two grooves of the head portion, it is possible to connect the rods alternately continuously without the need for a separate connector.

The rod has a martensite phase at or below 10 ° C., which is the transformation temperature of the shape memory alloy. Since it is installed in the state which changed the shape and length of a rod, it has the characteristic that installation work can be performed simply and quickly.

In addition, the rod includes a rod body portion having a bar shape, and an elastic portion having a diameter equal to the diameter of the rod body portion and formed in an arbitrary section of the rod body portion to exert an elastic force at an arbitrary impact strength. It can give the fluidity between and the node has a feature to reduce the burden on the waist.
As noted in the first and second embodiments of the present invention, the main feature of the present invention is the transformation from rigid rods with no elasticity to conventional rods with elastic parts. In particular, by forming one or two grooves in the bottom of the receiving groove of the head portion of the pedicle screw (site where the screw and the rod is connected) to simplify the operation by allowing the rod to be segmented, the elastic portion The prepared rod is made of a superelastic shape memory alloy (Nitinol alloy) to maximize flexibility and durability, and it is easy to operate with flexibility coming from the transformation temperature below 10 ° C of the shape memory alloy. It is.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings of FIGS. 4 to 10.

The pedicle fixation device according to the present invention can be easily connected by varying the shape and length of the rod even if the arrangement of the pedicle screws is not uniform using a rod made of a shape memory alloy, and exhibits elasticity when an arbitrary impact is applied. It is implemented to secure the fluidity between nodes.

Prior to describing an embodiment of the present invention, a known shape memory alloy made of a rod, which is a main part of the present invention, will be briefly described.

In general, the shape memory alloy refers to an alloy that has a characteristic of always returning to its original form at a predetermined temperature. For example, when a product is manufactured from the shape memory alloy, the shape is obtained by using it for a long time. Even if it differs a lot, it can be restored to its original form by adapting the previously designated or memorized temperature environment. That is, the shape memory alloy is transformed on martensite, and when heat is applied, the shape memory alloy is memorized and restored to its original shape on austenite. Such shape memory alloys have been substantially commercialized since the manufacture of nickel (Ni) / titanium (Ti) alloys, and are now copper / zinc, copper / aluminum / nickel, copper / aluminum / manganese, copper / tin, nickel / Many kinds of shape memory alloys such as aluminum, gold / copper / zinc alloys are known. Shape memory alloys are widely used in engineering and medical fields due to the fact that they always return to a specific shape at a specific temperature. For example, a shape memory alloy is used as an antenna of a satellite, a switchgear of a greenhouse window, an artificial joint, an orthodontic wire, and the like.

In the embodiment of the present invention, the rod is manufactured using the shape memory alloy which is harmless to the human body among these various shape memory alloys. In particular, the rod of the present invention is made of a Nitinol alloy (Ni-Ti alloy) having superelastic properties.

As shown in Figs. 4 to 6, the rod 10 in the first embodiment according to the present invention includes a rod body portion 11 having a bar shape in which both ends are bent in a “c” shape, and It is formed in any section of the center portion of the rod body portion 11 includes an elastic portion 12 that exerts an elastic force when an impact is provided to the rod. In particular, when the rod 10 having the above configuration is connected to the pedicle screw, it is connected in the form of a segment.

The elastic portion 12 is made of a coil spring structure, the diameter of the coil spring is the same as the diameter of the rod body portion (11). As another example, as shown in FIG. 7, the elastic part 12 may be formed in a continuous curved shape at a predetermined pitch interval. The diameter of the rod 10 is usually up to 2 to 7 mm, and is set at 0.5 mm intervals.

By the structure of the rod 10 as described above, when the rod is bent, twisted, or the external impact is applied to the waist while the rod is corrected by maintaining the interval and angle between the vertebrae properly. At this time, the elastic spring 12 of the coil spring or wave form exerts elasticity to act as a buffer between the node and the node.

The shape memory base material of the rod 10 has a martensite phase at a transformation temperature of 10 ° C. or less, and has a property of transforming to an austenite phase at 35 ° C. or more. In particular, the deformed rod maintains the deformed shape up to 26 ° C., and when the heat of a predetermined temperature is applied, the deformed rod is completely deformed at 35 ° C. while gradually deforming to the originally stored shape.

The rod 10 is bent at both ends of the shape-memory base material in the form of "c", and processed in the form of a coil in the center section, and manufactured by shape-memory heat treatment for about 1 hour at a temperature of 650 ~ 700 ℃ to change at a specific temperature It has the characteristics of the shape memory alloy. Therefore, since the rod 10 has a martensite state at about 10 ° C. or less, which is approximately the transformation temperature, its shape is easily deformed by external force at room temperature. And at 35 degreeC or more set by this invention by the shape recovery temperature which is a specific setting temperature, it is set so that it may transform into an austenite state.

The pedicle screw 20 has an accommodating groove 21a formed at an upper portion thereof, and at least one groove 22 that is axially exploded to seat the rod 10 at the bottom of the accommodating groove 21a. The formed head part 21 and the screw part 23 which are embedded in the upper and lower sides of the pedicle on the bottom face of the head part 21 are provided.

The pedicle screw 20 supports the rod 10, and is installed at an arbitrary interval on the upper and lower sides of the damaged pedicle to serve as a fixture.

The receiving groove 21a of the pedicle screw 20 is equipped with a set screw 30 to press the rod 10 to prevent the rod 10 from flowing. The set screw 30 has a male thread (30a) is formed on the outer circumferential surface, the wrench insertion groove (30b) is formed on the top.

A female thread 21b is formed on the inner circumferential surface of the accommodating groove 21a to allow the set screw 30 to be fastened in the accommodating groove 21a.

The pedicle screw 20 forms a rod fitting groove 24 for fitting the end of the rod 10 to the head portion 21 thereof. Therefore, after the rod 10 is inserted into the receiving groove 21a of the pedicle screw 20 and seated in the groove 22, the end of the "c" is inserted into the rod fitting groove 24 and fixed.

The head portion 21 of the pedicle screw 20 may further include a head cap 40 to prevent the head portion 21 from opening. The head cap 40 is additionally mounted as necessary, but is not essential.

On the other hand, the head portion 21, as a modification, shows an example in which two grooves 22, 22 'and two rod fitting grooves 24, 24' are formed as shown in Figs. 9A and 9B. . This is to install the rod 10 in the rod fitting groove 24 alternately without the need for a separate connector when the rod 10 is installed continuously.

In the first embodiment of the present invention, both ends of the rod 10 are bent in a "c" shape, and the pedicle screw 20 has a structure in which a groove 22 and a rod fitting groove 24 are provided. It is not limited to this. For example, the rod 10 is made of a shape memory alloy, the rod body portion 11 may be formed in a straight bar form or "b" shape is not bent. The rod 10 deformed in this way is firmly fixed by the set screw in the receiving groove of the head portion, there is no problem due to the flow. The rod 10 of the deformed structure includes a pedicle screw having a head portion having a female groove formed on the inner circumferential surface and a screw portion inserted into the pedicle, as in the conventional structure; It is applicable to a structure including a set screw fastened to the female screw formed in the receiving groove.

Next, a second embodiment of the present invention will be described with reference to FIG.

The same reference numerals are given to the same components as in the first embodiment described above.

As shown in the figure, the pedicle screw 20 has a head portion 21 formed with at least one first groove 56, 56 'for seating the rod 10 thereon, and the head portion 21 At the bottom of the head), a screw portion 23 is embedded in the upper and lower sides of the pedicle. In addition, a rod fitting groove 24 is formed at a lower portion on the same vertical axis as the first grooves 56 and 56 ', and a screw groove 57 is formed in the vicinity of the first grooves 56 and 56'. do.

The head cap 55 having the second grooves 59 and 59 ′ is formed at a bottom surface corresponding to the first grooves 56 and 56 ′ in the upper portion of the head portion 21. In addition, the head cap 55 is coupled to the head portion 21, but is provided with a fixing screw 58 is fastened to the screw groove 57 through the head cap 55. The fixing screw 58 prevents the rod 10 seated in the first grooves 26 and 26 'from flowing.

When one first groove 26 of the head portion 21 is formed, screw grooves 57 are formed on both sides of the first groove 26, and the first grooves 26 and 26 ′ are formed. When two are formed, the screw groove 57 is formed in the center part of them.

In this figure, an example in which two first grooves 26 and 26 'are formed is provided, which is provided for the case in which rods 10 are alternately and continuously installed.

Since the rod 10 has the same structure as that of the first embodiment, a detailed description thereof will be omitted.

Referring to the structure of the pedicle fixation device with reference to the first embodiment in the present invention configured as described above are as follows.

First, it is screwed in the vertical direction to each pedicle to be connected to the pedicle screw 20. And, before the rod 10 is inserted into the accommodating groove 21a of the pedicle screw 20, the length of the elastic portion 12 in the form of a coil spring is formed so that the rod 10 is transformed at room temperature (about 10 ° C). To increase. The rod body portion 11 of the rod 10 transformed in this way is seated in the groove 22 formed at the bottom of the receiving groove 21a of each pedicle screw 20, and the rod body portion 11 Insert the end of the letter "c" into the rod fitting groove 24 of the head portion (21).

In the above state, when the set screw 30 is fastened to the female thread 21b formed in the accommodating groove 21a of the head portion 21, and then the set screw 30 is tightened using a wrench, the set screw ( The installation of the rod 10 is completed by pressing the rod 10 at the bottom of the rod 30.

In this way, when the installation of the rod 10 is completed, by providing a heat of any temperature using a surgical instrument for generating a heat source such that the shape recovery temperature is 35 ℃ or more to the rod 10, the length is increased The elastic portion 12 section is transformed into an austenite state to restore the original length.

At this time, the end portion of the rod body portion 11 fitted in the rod fitting groove 22 is firmly fixed in the process of restoring the shape of the elastic portion 12 so that the rod body portion 11 of the rod fitting portion 22 is fixed. The end will not be separated.

As described above, even if the arrangement of the pedicle screw 20 is slightly misaligned, the rod fixing operation can be made very simple by bending the shape of the rod 10 by the displaced angle to adjust the position and performing the rod fixing operation. . In addition, the rod 10 is fixed by the elastic action that the elastic portion 12 is bent (bending) and then restored to its original state during bending or twisting motion according to the movement of the human body after the pedicle is fused This provides fluidity between the nodes.

On the other hand, in the installation process of the rod 10, in the case of connecting the rod in succession, as shown in Figure 10, two grooves 22, 22 'in the head portion 21 of the pedicle screw 20 The rod 10 is installed using the formed structure. At this time, the rod 10 installed in the inner groove 22 of the head portion 21 and the rod 10 'provided in the outer groove 22' are alternately installed. By using the head portion 21 in which the two grooves 22 and 22 'are formed in this way, a connector for continuous installation of a separate rod is not necessary.

As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example, A various change, a deformation | transformation are possible by a person with ordinary knowledge within the range of the technical idea of this invention. Will be apparent to those of ordinary skill in the art.

As described above, according to the present invention, by connecting the pedicle screw inserted into the pedicle at arbitrary intervals to maintain a constant spacing and angle between the vertebrae in the form of segments, each rod at a predetermined temperature By manufacturing the shape memory alloy to be transformed, when the rod is installed on the pedicle screw, the shape and length of the rod is transformed into an easy-to-install state, and then mounted on the pedicle screw, thereby simplifying the connection work. Although the arrangement of the pedicle screw is misaligned during the initial operation, it is possible to mount the rod after deforming the shape of the rod so that the rod installation work can be performed quickly, and by connecting the segmented rod to the pedicle screw alternately, It has the effect of making possible connection work.
In addition, the present invention provides a new connection method for fixing the spinal fixation device and the segment using a rod provided with an elastic portion, it is possible to treat the instability between the spinal segments and at the same time maintain the movement between the spinal segments, the conventional rigid rod ( There are other effects that reduce the side effects of surgical methods using rigid rods and make the surgery easier.

In addition, the present invention by molding a predetermined section of the rod with an elastic portion, the load is not concentrated between the plurality of fused pedicle nodes and nodes, can be distributed can reduce the burden on the waist. In addition, since the fluidity between the pedicle nodes is imparted, there is an effect that is fused to the normal spine shape of each patient. There is another effect that minimizes the complications of the upper and lower nodes with pedicle screws fixed, which are likely to occur many years after surgery.

Claims (11)

An accommodating groove is formed at an upper portion, and has a head portion formed with at least one groove formed in the bottom of the accommodating groove in an axial direction, and a screw portion embedded in the upper and lower sides of the pedicle at the bottom of the head portion serves as a fixing stand for the damaged pedicle. Pedicle screw; A rod consisting of a shape memory alloy that is transformed at a predetermined temperature, the rod being mounted on a ditch of the bottom of the receiving groove to connect the pedicle screws to correct the angle and spacing of the pedicle; And A fixing means inserted into the receiving groove of the pedicle screw and pressurizing the rod to prevent the rod from flowing; Pedicle fixation device comprising a. A pedicle screw that serves as a holder for a damaged pedicle by having a head portion having at least one first groove formed thereon, and a screw portion that is embedded in the upper and lower sides of the pedicle at the bottom of the head portion; A rod consisting of a shape memory alloy transformed at a predetermined temperature, the rod being mounted on the first groove of the head to connect the pedicle screws to correct the angle and spacing of the pedicle; A head cap positioned above the head portion and having at least one second groove formed at a bottom surface of the head portion corresponding to the first groove of the head portion; And Fixing means for fixing between the head cap and the pedicle screw, the pressing means to prevent the rod located between the first and second grooves to flow Pedicle fixation device comprising a. The method according to claim 1 or 2, The pedicle fixing device further comprises a rod fitting groove for fixing the end of the rod to the bottom of the receiving groove bottom portion of the head of the pedicle screw. The method according to claim 1 or 2, The rod has a martensite phase at or below 10 ° C., a transformation temperature of the shape memory alloy, and is transformed into an austenite phase at 35 ° C. or more. The method of claim 4, wherein The rod is And a rod body having a bar shape, and an elastic portion having a diameter equal to the diameter of the rod body and formed in an arbitrary section of the rod body to exert an elastic force when an impact is applied. The method of claim 5, The pedicle fixation device, characterized in that the elastic portion made of a coil form. The method of claim 5, The pedicle fixation device, characterized in that the elastic portion made of a wave form. The method of claim 1, The receiving groove of the head is formed with a female thread on the inner circumferential surface, The fixing means is a pedicle fixing device characterized in that the male thread is formed on the outer circumferential surface to be fastened to the female thread, the set screw formed with a wrench insertion groove in the upper portion. The method of claim 2, The fixing means A pedicle fixation device including a fixing screw groove formed at a predetermined depth in a proximal portion of the first groove, and a screw penetrating the head cap to the fixing screw groove. The method according to claim 1 or 2, A pedicle fixation apparatus, characterized in that two first grooves of the head are formed so that the rods can be connected alternately and continuously. The method of claim 1, Covering the outer circumference of the head, the pedicle fixing device further comprises a head cap for preventing the head from opening.

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