KR101209294B1 - Transport bone disc distractor for curvilinear motion - Google Patents

Abstract

PURPOSE: A bone distracter for a curvilinear motion is provided to be easily applied to a curved part of a bone by curvilinear motion corresponding to the curved part of a bone tissue. CONSTITUTION: A first fixing unit(110) and a second fixing unit(112) are fixed to a first bone and a second bone. A bone piece fixing unit(120) fixes a bone piece from the first bone or the second bone. The bone piece fixing unit includes a shaft combining unit(120A) and a guide bar combining unit(120B). A shaft(130) controls a distance of the bone piece between the first bone and the second bone. A pair of guide bars(140) guide the bone piece fixing unit according to the linear motion and rotation of a shaft.

Description

Bone stretcher with curve movement {TRANSPORT BONE DISC DISTRACTOR FOR CURVILINEAR MOTION}

The present invention relates to a bone stretcher capable of curved movement, and more particularly, to correct the malformation of the curved portion of the human bone tissue or to perform a curved movement corresponding to the curved portion of the bone tissue when regenerating bone tissue lost accidentally. It is related to a bone expander capable of curved movement.

In general, various surgical procedures such as magnetic bone grafts or artificial bone grafts have been applied to treat a widespread defect in the skull and a wide defect in the facial bone after extensive trauma including cranial and facial fractures and bone defects. .

However, magnetic bone graft requires additional surgery away from the defect to use the bones such as the hips, and there is a problem that additional infection and additional complications of the bone donor site may occur during this process. Transplantation of animal bones is difficult to completely rule out the side effects caused by the genetic differences between the bones provided and the patients undergoing the procedure, the bone strength decreases after successful transplantation, fibrosis and chronic infection of surrounding tissues There were problems that could arise with this addition.

Bone nephrectomy, which has recently been introduced, is a treatment technique that can overcome such problems. It is to gradually move to form a new bone between the moving and fixed bone fragments.

Here, the bone elongation separates the bone fragments to be moved first, and then when the traction is applied to the healing callus (Healing Callus) that combines the separated bone fragments, the extension of the bone tissue starts, and artificial traction is applied to the bone tissue During this period, new bone tissue is formed in the kidney area along with bone regeneration, which is accompanied by regeneration of new bone. Various tissues, including active tissue formation and elongation corresponding to the tensile direction, also occur.

Such bone nephrectomy began to be applied mainly to the limbs that induce new bone formation, and now it is extended to the skull and facial area, and in the case of craniofacial face (head and jaw-face) in 1992, McCarthy ( Since McCarthy's first extension of the mandible (mandibular jaw) using human extraoral devices, many clinicians have been applying bone reconstruction to reconstruct congenital, developmental malformations or other facial defects in the cranial face. .

However, when congenital, developmental malformations and defects occur in areas having different curved structures, such as the skull, cranial facial part, and mandibular bone, bone elongators composed of conventional straight lines are provided to provide a strong tensile force on the missing curved bone. There is a problem that it is difficult to apply.

In particular, the above-mentioned treatment method enables the treatment by increasing the length or volume of the jaw-facial deformity deformity bone, but if the bone defect is extensively lower without treating the bone defect after trauma or malignancy, the missing bone is a complex curved surface. Unless autologous bone graft is performed, restrictive treatment methods such as implantation of suitable curved metals and implantation into the defects are inevitably carried out, and bone tissues having curved structures such as facial or skull When regeneration is required and when a portion has a curved moving surface corresponding to a different curved structure, there is a problem that it is difficult to reconstruct bone tissue using an existing bone expander.
Therefore, there has been a demand for research and development on bone expander which can be easily applied to the curved portion of bone when correcting or regenerating bone tissue of the human body. Accordingly, the present applicant has developed the present invention with the support of the technical development project of Seoul, and the contents thereof are as follows.
1.Project Number: PA100085
2. Supporting organization: Seoul Development Institute
3. Task name: Commercialization of steel wire bone elongator

The technical problem of the present invention is to provide a bone elongator capable of performing a curved motion corresponding to a curved portion of a bone tissue when correcting an anomaly on a curved portion of a human bone tissue or regenerating an accidentally lost bone tissue. .

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. There will be.

The technical problem, according to the present invention, the first fixing part and the second fixing part provided at a predetermined interval apart from each other so as to be fixed to the first bone and the second bone provided in a curved surface on both sides of the bone defect; A bone piece fixing part provided between the first fixing part and the second fixing part to fix the bone piece that is separated from the first bone or the second bone; It is provided to rotate and relative linear movement with respect to the second fixing part after being coupled to the bone piece fixing part through the first fixing part to adjust the separation distance of the bone piece between the first bone and the second bone. Shaft; And a pair of guide bars configured to guide the bone piece fixing part in accordance with rotation and linear movement of the shaft to be curved in correspondence with the first bone and the second bone. Is achieved by an expander.

The bone piece fixing portion, the shaft coupling portion to which the shaft is rotatably coupled; And a guide bar coupling part coupled to both ends of the shaft coupling part to allow the guide bar to penetrate therebetween and provided to guide the hinge bar relative to the shaft fixing part when guided along the guide bar.

In the guide bar coupling portion, a guide hole may be formed to allow the guide bar to pass therethrough.

Inside the guide hole, the guide-packing of the tubular shape is provided to be elastically deformed to the extent that the curved movement of the guide bar coupling portion can be coupled.

The shaft, the hollow having a drug injection passage therein to inject drugs using the syringe in the bone defects in accordance with the distance control of the bone piece fixing portion relative to the first fixing portion and the second fixing portion It can be formed into a shaft of the mold.

The shaft is formed with a recess recessed from the surface on the inlet side of the drug injection passage, the groove may be provided with a stopper coupled to block the entry of other foreign substances except the drug into the drug injection passage.

The stopper may be formed of a rubber or silicone material having self-elasticity to allow insertion of the syringe needle and to close a hole formed upon insertion of the needle after completion of injection of the drug.

The shaft may have a screw portion formed around the surface of the shaft to adjust the separation distance of the bone piece fixing portion with respect to the first fixing portion and the second fixing portion.

The pair of guide bars are formed to be curved to guide and curve the bone piece fixing part as the shaft rotates, and guide bars having both ends coupled to opposite surfaces of the first fixing part and the second fixing part. Can be.

At least one first screw hole is formed at both ends of the first fixing part and the second fixing part so as to be fixed to the first bone and the second bone, and the bone piece fixing part is fixed to the bone piece. At least one second screw hole may be formed at both ends thereof so as to be formed therethrough.

Two first screw holes may be provided in line at both ends of the first fixing part and the second fixing part, and the second screw holes may be provided at each of both ends of the bone piece fixing part.

The present invention guides along the guide bar to adjust the separation distance of the bone piece relative to the first bone and the second bone between the first and second fixing portions in accordance with the rotation and relative linear motion of the shaft relative to the second fixing portion. By providing a bone stretcher capable of curved movement having a bone fragment fixing portion is provided to be curved movement, it can be easily applied to the flexible portion of the bone, such as the face or skull during regeneration of bone tissue of the human body.

1 is a perspective view of a bone expander capable of curved movement according to an embodiment of the present invention.
2 is a front view of the bone expander capable of the curved motion of FIG.
3 is a front sectional view of the bone expander capable of the curved motion of FIG.
4 is a cross-sectional plan view of the bone expander capable of the curved motion of FIG.
5 is an operating state diagram of the bone expander capable of curved movement according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, the well-known functions or constructions are not described in order to simplify the gist of the present invention.

1 is a perspective view of a bone expander capable of curved movement according to an embodiment of the present invention, Figure 2 is a front view of the bone expander capable of curved movement of Figure 1, Figure 3 is a bone expander of the curved movement of Figure 1 Figure 4 is a front cross-sectional view, Figure 4 is a planar cross-sectional view of the bone expander capable of curved motion of Figure 1, Figure 5 is a diagram showing the operating state of the bone expander capable of curved movement according to an embodiment of the present invention.

Curved bone expander 100 according to an embodiment of the present invention, as shown in Figures 1 to 4, the first bone (S1) and the first provided in a curved surface on both sides of the bone defect (S) 2, the first fixing part 110 and the second fixing part 112 provided to be fixed to the bone S2, and the bone piece S3 separated from the first bone S1 or the second bone S2. The bone piece fixing part 120 provided between the first fixing part 110 and the second fixing part 112 so as to be fixed, and the bone piece S3 between the first bone S1 and the second bone S2. The shaft 130 is provided to rotate and relative linear movement with respect to the second fixing part 112 to adjust the separation distance of the bone, and the bone piece fixing part 120 is guided according to the rotation of the shaft 130 is curved It includes a pair of guide bar 140 provided to exercise.

The first fixing part 110 and the second fixing part 112 are formed to be spaced apart from each other so as to be fixed to the first bone S1 and the second bone S2 provided at both sides of the bone defect S. And the coupling part 114 is provided. That is, the first fixing part 110 and the second fixing part 112 are provided with curved surfaces on both sides of the bone defect (S) in order to regenerate the bone tissue lost in the correction or accident of the curved portion of the bone tissue. It is fixed to the first bone S1 and the second bone S2, respectively.

Screws (not shown in the drawing) are inserted at both ends of the first fixing part 110 and the second fixing part 112 so as to be engaged with the first bone S1 and the second bone S2, respectively. Two first screw holes 113 are formed so that the first bone S1 and the second bone S2 are first fixed by the screw inserted into the first screw hole 113. And it can be firmly fixed to the second fixing part (112).

In this case, the number of the first screw holes 113 is provided to be disposed at two or more lines at both ends of the first fixing part 110 and the second fixing part 112 or a plurality of them are arranged up, down, left and right. It may be variously changed, such as provided.

Coupling portion 114 is configured to be coupled to the pair of guide bar 140 to maintain the parallel to the first fixing portion 110 and the second fixing portion 112. That is, the coupling part 114 is disposed on the opposite surface of the first fixing part 110 and the second fixing part 112 at regular intervals so as to insert both ends of the guide bar 140 recessed from the surface It is formed into a shape. Accordingly, the guide bar 140 may be coupled to guide the bone piece fixing part 120 between the first fixing part 110 and the second fixing part 112.

The bone piece fixing part 120 is configured to fix the bone piece S3, and is coupled to the shaft coupling part 120A to which the shaft 130 is coupled and to both ends of the shaft coupling part 120A. Guide bar coupling portion 120B is included.

The bone piece fixing part 120 is disposed between the first fixing part 110 and the second fixing part 112 to be guided along the guide bar 140.

The shaft coupling part 120A is configured to rotatably couple the shaft 130 penetrating the first fixing part 110. That is, the shaft coupling portion 120A is rotatably coupled to the front end portion of the shaft 130 penetrating the first fixing portion 110.

The guide bar coupling portion 120B is coupled to the relative hinge movement with respect to the shaft coupling portion 120A, and the guide hole 122 is provided.

That is, the guide bar coupling portion 120B is coupled to both ends of the shaft coupling portion 120A via the hinge 121, and thus, the guide hinge 120 is coupled relative to the shaft coupling portion 120A when guided along the guide bar 140. By movement, the curved movement of the bone piece fixing part 120 is enabled.

At both ends of the guide bar coupling portion 120B, a second screw hole 121 is formed to be inserted into each other so that a screw (not shown in the drawing) may be inserted and fastened to the bone piece S3, thereby forming the bone piece S3. The silver can be firmly fixed to the bone piece fixing portion 120 via a screw inserted into the second screw hole (121).

Here, the number of the second screw holes 121 may be variously changed, such that the number of the second screw holes 121 is provided to be arranged at one or both ends of the guide bar coupling portion 120B in a row, or the plurality of the second screw holes 121 is arranged to be arranged up, down, left, and right. .

The bone fragment S3 is bone tissue separated into a predetermined size from the first bone S1 or the second bone S2 for the procedure of bone elongation.

Guide hole 122, the guide bar 140 is formed so as to penetrate through the structure is provided with a guide packing 124 therein. That is, the guide hole 122 is formed so that the guide bar 140 penetrates and coupled to both ends of the guide bar coupling portion 120B.

The guide packing 124 is a structure provided in the guide hole 122. That is, the guide packing 124 is formed in a tubular shape and is coupled to prevent the departure from the inside of the guide hole 122 so that the guide bar 140 can penetrate. In this case, the guide packing 124 is formed of a silicone or rubber material that is elastically deformed to enable the curved movement when the bone piece fixing part 120 is guided along the guide bar 140.

That is, the guide packing 124 is a guide bar when the guide bar coupling portion 120B is guided in the longitudinal direction of the guide bar 140 for the curved movement of the bone piece fixing part 120 by the rotation of the shaft 130 ( According to the curved structure of 140) it is elastically deformed.

The shaft 130 is formed to adjust the separation distance of the bone piece (S3) between the first bone (S1) and the second bone (S2) and is a configuration in which the drug injection passage 132 and the stopper 134 is provided. . A thread 131 is formed around the surface of the shaft 130 to be screwed to penetrate the second fixing part 112, and then the front end thereof is coupled to the bone piece fixing part 120 to prevent separation. At this time, the second fixing part 112 is formed with a screw portion (not shown) corresponding to the screw portion 131 formed on the shaft 130.

The shaft 130 is rotated and relative linear movement relative to the second fixing portion 112, so that the bone piece fixing portion 120 is guided in the longitudinal direction of the guide bar 140, the first bone (S1) and the second The distance between the bone pieces S3 is adjusted between the first fixing part 110 and the second fixing part 112 fixed to the bone S2.

The drug injection passage 132 is a structure provided inside the shaft 130. At this time, the shaft 130 is formed in a hollow to form a drug injection passage 132 therein. The drug injection passage 132 is a drug required for bone regeneration in the bone defects (S) in accordance with the separation distance control of the bone fragment fixing part 120 in the first fixing part 110 and the second fixing part 112. To inject.

The drug injected into the bone defects (S) for bone regeneration is a bone morphogenetic protein (BMP) that is directly involved in bone formation. The cDNA of these proteins replicates nine types of BMPs (BMP-1 to BMP-9) to date. BMP-3 is also called osteogenin, BMP-7 is OP-1, and BMP-6 is also called Vgr-1. Except for BMP-1, others belong to the transgenic patient β (TGF-β) superfamily. In BMP-2 to BMP-9, 110 to 140 amino acids of the C terminus are expressed by forming a homo or heterodimer. When transplanted into BMP muscle, cartilage is first formed (5 ~ 7 days after transplantation). When capillaries invade cartilage tissue, cartilage is absorbed, bone marrow is replaced with bone marrow, and ectopic bone tissue is formed in the muscle (graft). About 3 weeks). In addition to bone formation, BMP is involved in the formation of fruit flies and tadpoles. Human BMP-2 and BMP-4 are highly homologous to the Drosophila form factor Dpp, and human BMP-5 to BMP-8 are similar to Drosophila 60A. Since transplantation of Dpp or 60A into mice induces bone formation, it is speculated that BMP activity is determined not by the characteristics of BMP itself but by the cells of the recipient.

However, if necessary, other drugs other than the above-described drugs may be used, and the claims of the present invention are not limited by the types of drugs.

The stopper 134 is configured to be coupled to the shaft 130. That is, the stopper 134 is coupled to the groove 133 formed on the inlet side of the drug injection passage 132 provided on the shaft 130 to prevent the entry of other foreign substances except the drug into the drug injection passage 132. Prepared.

Here, the stopper 134 of the present embodiment is coupled to be inserted into the recess 133 formed at the inlet side of the drug injection passage 132, but in another embodiment of the present invention, the stopper 134 of the drug injection passage 132 It may be provided to surround the entrance.

The stopper 134 allows the drug to be injected into the drug injection passage 132 provided on the shaft 130 using a syringe (not shown).

That is, the stopper 134 is formed of a rubber or silicone material having a self-elasticity to allow the insertion of the syringe needle and to close the hole formed by the insertion of the needle after the injection of the drug is completed, thus the drug injection passage 132 As a result, it is possible to prevent the entry of foreign substances other than drugs.

The pair of guide bars 140 are configured to guide the curved bone fixing portion 120 to be curved. That is, the guide bar 140 is formed to be curved so that the bone piece fixing part 120 can perform a curved motion corresponding to the curved surface of the first bone S1 and the second bone S2 of the bone defect S. It is coupled between the first fixing part 110 and the second fixing part 112.

The guide bar 140 allows the bone piece fixing part 120 to be guided during the rotation and linear movement of the shaft 130 to allow a curved motion corresponding to the curved surfaces of the first bone S1 and the second bone S2. .

That is, the guide bar 140 is a bone piece fixing part 120 is the first fixing part 110 and the second fixing part 112 by the shaft 130 that rotates and relative linear movement with respect to the second fixing part (112). The first bone (S1) and the second bone (S2) provided in the bone defect (S) guided to adjust the separation distance of the bone piece (S3) with respect to the first bone (S1) and the second bone (S2) between) It is to allow the curve movement to correspond to the curved surface of).

Hereinafter, with reference to Figure 5 will be described the operation of the bone expander capable of curve movement according to an embodiment of the present invention.

As shown in FIG. 5, in order to correct an anomaly for a curved portion of a bone tissue of a human body or to perform a bone elongation according to an accidental regeneration of bone tissue, a bone defect (S) requiring regeneration of bone tissue is required. The first fixing part 110 and the second fixing part 112 are fixed to the first bone S1 and the second bone S2, respectively, and are disposed between the first fixing part 110 and the second fixing part 112. Fix the bone piece (S3) to the bone piece fixing portion 120 to be.

When the first fixing part 110 and the second fixing part 112 are fixed to the first bone S1 and the second bone S2, respectively, and the bone piece fixing part 120 is fixed to the bone piece S3, the shaft ( By rotating 130, the distance between the bone piece fixing part 120 with respect to the first fixing part 110 and the second fixing part 112 is adjusted.

That is, the shaft 130 is rotated relative to the second fixing part 112 and relative linear motion, and thus the bone piece fixing part 120 is guided along the curved guide bar 140 formed to be curved to correspond to the curved surface of the bone tissue. By exercising, the distance between the first bone S1 and the second bone 112 and the first bone S1 and the second bone S2 to adjust the separation distance of the bone piece S3.

At this time, the bone piece fixing part 120 is a guide bar for the shaft coupling portion (120A) in the process of being guided along the guide bar 140, unlike the shaft 130 that moves relative linearly relative to the second fixing part (112) Curved motion corresponding to the curved structure of the guide bar 140 by the relative hinge movement of the coupling portion 120B and the elastic deformation of the guide packing 124 coupled to the guide hole 122 of the guide bar coupling portion 120B. Done.

That is, when the bone piece fixing part 120 is guided along the guide bar 140, the guide packing coupled to the guide hole 122 while the guide bar coupling part 120B is hinged relative to the shaft coupling part 120A. Since 124 is elastically deformed according to the curved structure of the guide bar 140, the curved motion corresponding to the curved structure of the guide bar 140 is achieved.

The distance of the bone fragments S3 is adjusted in the bone defect S, which requires the regeneration of bone tissue, by adjusting the separation distance of the bone fragment fixing part 120 with respect to the first fixing part 110 and the second fixing part 112. Then, the drug is injected into the bone defect (S) to promote the regeneration of bone tissue through the drug injection passage 132 provided inside the shaft 130 using a syringe.

That is, the drug injected through the drug injection passage 132 is injected into the bone defect (S) through the tip of the shaft 130. At this time, as the stopper 134 is provided at the inlet side of the drug injection passage 132, the syringe needle is inserted into the stopper 134 to inject the drug into the drug injection passage 132, and then the syringe needle is separated. The hole thus formed is restored to be naturally blocked by the elasticity of the stopper 134. Accordingly, it is possible to prevent the entry of other foreign matter other than the drug into the drug injection passage (132).

When the drug is injected into the bone defect (S) that requires regeneration of bone tissue through the drug injection passage 132 of the shaft 130, it is left for a certain period (4 days to 10 days) to mature and coalesce the bone and then to the shaft. According to the operation of the operation 130 and the curved movement of the bone piece fixing part 120, the distance of the bone fragments (S3) in the bone defect (S) is extended and the process of injecting drugs is repeated to extend the bone continuously. At this time, the length of the bone is 1 mm per day.

When the bone is continuously stretched, bone regeneration is terminated by removing the bone retractor and closing the incision site after maturation and union between the new bone tissue and the existing bone tissue are confirmed through the bone strengthening period of 6 to 8 weeks.

As described above, the bone expander 100 having a curved motion according to an embodiment of the present invention may include a first fixing part according to rotation and relative linear motion of the shaft 130 with respect to the second fixing part 112. It may be curved along the guide bar 140 to adjust the separation distance of the bone piece (S3) with respect to the first bone (S1) and the second bone (S2) between the 110 and the second fixing portion (112). By the bone piece fixing portion 120 is provided so that it can be easily applied to the curved portion of the bone, such as the face or skull during regeneration of the human bone tissue.

In addition, by providing a drug injection passage 132 having a stopper 134 on the shaft 130, it is possible to inject the drug using a syringe into the bone defect (S) during bone tissue regeneration, thereby promoting bone tissue regeneration While improving the therapeutic effect, it can prevent the introduction of foreign substances other than drugs.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious to those who have. Therefore, such modifications or variations are not to be understood individually from the technical spirit or point of view of the present invention, the modified embodiments will belong to the claims of the present invention.

110: first fixing part 112: second fixing part
114: coupling portion 120: bone piece fixing portion
120A: Shaft Coupling Part 120B: Guide Bar Coupling Part
122: guide 124: guide packing
130: shaft 132: drug injection passage
134: stopper 140: information bar

Claims (11)

A first fixing part and a second fixing part spaced apart from each other to be fixed to the first bone and the second bone which are curved on both sides of the bone defect part;
A bone piece fixing part provided between the first fixing part and the second fixing part to fix the bone piece that is separated from the first bone or the second bone;
It is provided to rotate and relative linear movement with respect to the second fixing part after being coupled to the bone piece fixing part through the first fixing part to adjust the separation distance of the bone piece between the first bone and the second bone. Shaft; And
The bone expander is capable of performing a curved movement according to the rotation and linear movement of the shaft includes a pair of guide bars which are provided to guide the curved movement corresponding to the first bone and the second bone. . The method of claim 1,
The bone piece fixing part,
A shaft coupling part to which the shaft is rotatably coupled; And
And a guide bar coupling portion coupled to both ends of the shaft coupling portion to penetrate the guide bar, the guide bar coupling portion being configured to move relative to the shaft fixing portion when guided along the guide bar. The method of claim 2,
The guide bar coupling portion,
Bone stretcher capable of curved movement, characterized in that the guide hole is formed so that the guide bar can penetrate. The method of claim 3,
Inside the guide hole,
Curved movement possible bone expander, characterized in that the guide packing of the tubular shape provided to be elastically deformed to the extent that the curved movement of the guide bar coupling portion is coupled. The method of claim 1,
The shaft includes:
In accordance with the adjustment of the distance of the bone piece fixing portion relative to the first fixing portion and the second fixing portion by the hollow shaft having a drug injection passage therein to inject drugs using the syringe in the bone defect Bone stretcher capable of curved movement, characterized in that formed. The method of claim 5,
The shaft includes:
Grooves recessed from the surface is formed at the inlet side of the drug injection passage,
In the groove,
Curved movement possible bone expander, characterized in that the stopper is provided to be coupled to block the inflow of other foreign substances other than the drug into the drug injection passage. The method according to claim 6,
The stopper may be inserted into the syringe needle and the curved movement of the bone expander, characterized in that formed of a rubber or silicone material having a self-elasticity to close the hole formed by the insertion of the needle after completion of the injection of the drug . The method of claim 1,
The shaft includes:
Curved bone expandable bone stretcher, characterized in that the thread is formed around the surface to adjust the distance of the bone piece fixing portion relative to the first fixing portion and the second fixing portion. The method of claim 1,
The pair of guide bars,
Curved movement is characterized in that the guide bar is formed so as to be curved to guide the curved portion of the bone piece fixing according to the rotation of the shaft and both ends coupled to the opposite surface of the first fixing portion and the second fixing portion. Bone elongation. The method of claim 1,
In the first fixing portion and the second fixing portion,
At least one first screw hole is formed at both ends thereof so as to be fixed to the first bone and the second bone,
In the bone piece fixing part,
At least one second threaded hole is formed at both ends to be fixed to the bone piece, the bone expander capable of curve movement. The method of claim 10,
The first screw hole is provided in each of two ends of the first fixing part and the second fixing part in a row,
The second screw hole is a bone expander capable of curved movement, characterized in that provided in each of both ends of the bone piece fixing portion.

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