WO2018164034A1 - Fixator - Google Patents

Abstract

Provided is a bone fixator capable of reducing risks to a human body and having a simple structure. This fixator (10) is provided with: pedicle screws (12, 14) fixed to first and second mounted portions (24, 26) of a bone, respectively; first and second vibration members (16, 18); and a rod (20). The first vibration member (16) is provided with a first screw (16a) comprising a right-hand thread, and fixed to the pedicle screw (12) so as to be able to vibrate. The second vibration member (18) is provided with a second screw (18a) comprising a left-hand thread, and fixed to the pedicle screw (14) so as to be able to vibrate. The rod (20) has a third screw (20a) at one end and a fourth screw (20b) at the other end. The third screw (20a) engages with the first screw (16a) and the fourth screw (20b) engages with the second screw (18a). The second vibration member (18), when receiving ultrasonic waves oscillated from the outside of the body, deforms while vibrating, and the rod (20) rotates while being pressed against by the second vibration member (18); accordingly, the distance between the pedicle screws (12, 14), that is, the distance between the first and second mounted parts (24, 26) is increased or decreased.

Description

Fixture

The present invention mainly relates to a fixture for fixing a bone.

If the scoliosis where the spine is curved or twisted is left unattended, serious damage to the internal organs may occur. In order to correct the curvature and torsion of the spinal column, spinal fusion is performed in which an auxiliary tool such as a metal shaft is fixed to the spine inside the human body. This aid is fixed in the body for a long time until the condition of scoliosis is improved. Therefore, it is necessary to change the length of the assisting device according to the patient's growth and treatment conditions. Conventionally, since the affected part was opened with a scalpel and the auxiliary tool was exchanged, the burden on the patient was large.

In recent years, a method for adjusting the length of a minimally invasive auxiliary tool using an endoscope or the like has been proposed. However, incision is required even with a less burdensome technique such as endoscopic surgery, and there is a risk of damage to the dura mater covering the nerves and complications. If the length of the assistive device is required to be adjusted multiple times, such as a juvenile disease, this is an unacceptably large risk. For this reason, a technique for adjusting the length of the auxiliary tool without performing incision is necessary. As a technique for adjusting the length of a non-invasive auxiliary tool that does not require incision, a technique for expanding / contracting the auxiliary tool in the body by magnetic irradiation from outside the body is known (Non-Patent Document 1). Such auxiliary tools that can be expanded and contracted by magnetism have been commercialized and used in other countries as glowing rods and the like.

Cheung KM, Cheung JP, Samartzis D, Mak KC, Wong YW, Cheung WY, Akbarnia BA, Luk KD: Magnetically controlled growing rods for severe spinal curvature in young children: a prospectivespp 1967-1974, 2012

There are many unclear points about the effects of magnetic irradiation on the human body, and the risks have been reported. For this reason, it is difficult to control the risk of an auxiliary tool that can be expanded and contracted by magnetic irradiation. In addition, an auxiliary tool that can be expanded and contracted by magnetic irradiation is difficult to use together with a device that should eliminate the influence of magnetism as much as possible, such as a pacemaker. In addition, the extendable auxiliary tools that are currently commercialized are very complex in structure and have a high risk of failure.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a bone fastener that can reduce the risk to the human body while having a simple structure.

A fixing device according to an aspect of the present invention includes a first support member fixed to the first mounting portion, a second support member fixed to the second mounting portion, and a first screw at one end, the first support member A first connection member fixed to the first support member and a second screw opposite to the direction of the first screw at one end so that the one end is disposed between the first support member and the second support member. A second connecting member fixed to the second supporting member and a third screw fitted to the first screw at one end, so that the one end is disposed between the one supporting member and the second supporting member; A fourth screw that fits with the second screw is provided at the end, the first connecting member is fitted to this one end, the second connecting member is fitted to this other end, and a vibrating member that vibrates in response to a vibration wave is provided. Have. The fixing member changes its shape while receiving vibration waves oscillated from the outside, and the vibration member is vibrated, and the vibration member pressed by the first connection member and the second connection member rotates, whereby the first support member And the distance between the second support member is increased or decreased.

The fixing device according to another aspect of the present invention includes a first support member fixed to the first mounting portion, a second support member fixed to the second mounting portion, and a first screw, and is capable of vibrating first. A first vibration member that is fixed to the support member and vibrates in response to a vibration wave, and a second screw that is opposite to the direction of the first screw, is fixed to the second support member so as to vibrate and receives the vibration wave. A second vibrating member that vibrates, a third screw that engages with the first screw at one end, and a fourth screw that engages with the second screw at the other end, each having one end at the first vibrating member and the other The end has a connecting member fitted to the second vibrating member. The fixture receives a vibration wave oscillated from the outside, changes its shape while vibrating at least one of the first vibration member and the second vibration member, and is pressed by at least one of the first vibration member and the second vibration member. As the connecting member rotates, the distance between the first support member and the second support member increases or decreases.

The fixing device of the present invention has a long-term use record in the medical field, and can be expanded and contracted using vibration waves such as ultrasonic waves that do not adversely affect the human body at low output. Risk to the human body can be reduced compared to tools. Moreover, since the fixture of this invention can be comprised mainly from members, such as a volt | bolt and a nut, it can be made a simple structure and can reduce the risk of failure.

Sectional drawing of the fixing tool which concerns on 1st embodiment of this invention. The perspective view of the fixing tool which concerns on 1st embodiment of this invention. The exploded view of the fixture concerning a first embodiment of the present invention. It is a figure which shows the 1st vibration member of the fixing tool which concerns on 1st embodiment of this invention, (a) is a perspective view from the left, (b) is annular sectional drawing. Sectional drawing for demonstrating a deformation | transformation of the 1st vibration member of the fixing tool which concerns on 1st embodiment of this invention. The side view for demonstrating the mechanism in which the fixing tool which concerns on 1st embodiment of this invention extends. The side view for demonstrating the mechanism which the fixing tool which concerns on 1st embodiment of this invention shrinks. Sectional drawing of the fixing tool which concerns on 2nd embodiment of this invention. The perspective view of the fixing tool which concerns on 2nd embodiment of this invention. The exploded view of the fixing tool concerning a second embodiment of the present invention. Sectional drawing of the vibration member of the fixing tool which concerns on 2nd embodiment of this invention. It is a figure which shows the rod of the fixing tool which concerns on 2nd embodiment of this invention, (a) is a perspective view from the right, (b) is a right view. Sectional drawing for demonstrating the mechanism in which the fixing tool which concerns on 2nd embodiment of this invention extends. The right view of the rod of the fixing tool which concerns on the modification of 2nd embodiment of this invention.

Hereinafter, the fixing device of the present invention will be described with reference to the drawings based on an embodiment used for spinal fusion and an example in which the operation of the vibration member is confirmed. The drawings schematically show the fixture, the constituent members of the fixture, and the peripheral members of the fixture, and the actual dimensions and ratios of these objects are not necessarily the same as the dimensions and dimension ratios on the drawings. I have not done it. Unless otherwise specified, in this specification, for the sake of convenience, the vertical direction and the horizontal direction are expressed with reference to the orientation of the fixture shown in FIGS. 1 and 8. In addition, duplication description is abbreviate | omitted suitably and the same code | symbol may be provided to the same member.

As described above, the present invention relates to a fixture for fixing bone. As the utilization of the fixing device of the present invention, there is a fixing device for fixing the spine mainly for treatment of vertebral fractures and correction of spinal curvature. In the following description, a form used for spinal fusion for fixing the spine will be described as an example. Note that the present invention is not limited to the spine and vertebra, and can be used to fix other bones.

(First embodiment)
FIG. 1 is a cross-sectional view of a fixture 10 according to a first embodiment of the present invention. FIG. 2 is a perspective view of the fixture 10. FIG. 3 is an exploded view of the fixture 10. The fixture 10 is a connecting member having a pedicle screw 12 as a first support member, a pedicle screw 14 as a second support member, a first vibration member 16, a second vibration member 18, and a column shape. A certain rod 20 is provided. The pedicle screw 12 is made of a metal having excellent biocompatibility, such as titanium, a titanium alloy, or a cobalt chromium alloy, and is screwed and fixed to the vertebra 24 (first mounting portion) of the human spine 22. Similarly, the pedicle screw 14 is made of a metal excellent in biocompatibility, and is screwed and fixed to the other vertebra 26 (second mounting portion) of the spine 22.

The first vibrating member 16 is made of a metal excellent in biocompatibility, and vibrates in response to a vibration wave oscillated from outside the body. In each embodiment, a case where the vibration wave is an ultrasonic wave will be described as an example. The first vibration member 16 is a nut-like member having a cylindrical shape with an outer diameter of about 6 mm and a length of about 3 mm, and a first screw 16a of a right-hand thread formed on the inner surface of the cylinder. The first vibration member 16 is fixed to the pedicle screw 12 so as to vibrate. Specifically, as shown in FIG. 1, the first vibration member 16 is placed on the pedicle screw 12 so that the opening of the first vibration member 16 faces the pedicle screw 14, and the first vibration amplification is performed. It is fixed from above with a rod fixture 30 made of metal having excellent biocompatibility via the member 28. At this time, the first vibrating member 16 is fixed so as not to move easily, and at such a strength that it can vibrate on the spot upon receiving an ultrasonic wave.

The second vibrating member 18 is made of a metal excellent in biocompatibility, and vibrates in response to ultrasonic waves oscillated from outside the body. The second vibrating member 18 has a cylindrical shape with an outer diameter of about 6 mm and a length of about 3 mm, and a second screw 18 a of a left-hand thread opposite to the direction of the first screw 16 a is formed on the inner surface of the cylinder. It is a nut-like member. That is, the shape of the second vibrating member 18 is the same as the shape of the first vibrating member 16 except for the direction of the screw formed on the inner surface. The first screw 16a may be a left-hand screw and the second screw 18a may be a right-hand screw.

The first screw 16a and the second screw 18a are female screws having a special shape different from a general helical female screw. Detailed structures of the first screw 16a and the second screw 18a will be described later. Like the first vibration member 16, the second vibration member 18 is strong enough to vibrate on the spot without being easily moved, and is excellent in biocompatibility via the second vibration amplification member 32. It is fixed to the pedicle screw 14 with a rod fixture 34 made of metal. The rod fixtures 30, 34 may be screws (fifth screw, sixth screw) as shown.

The rod 20 is made of a metal excellent in biocompatibility and has screws formed at both ends. That is, the rod 20 has a third screw 20a fitted to the first screw 16a on the outer surface of one end, and a fourth screw 20b fitted to the second screw 18a on the outer surface of the other end. . The third screw 20a and the fourth screw 20b are general helical male screws. And in the fixture 10, this one end is fitted so that the 1st vibration member 16 and this other end may contact the 2nd vibration member 18 weakly, respectively.

At least one of the first vibrating member 16 and the second vibrating member 18 vibrates in response to ultrasonic waves oscillated from outside the body by an ultrasonic oscillator or the like. Although details will be described later, the rod 20 is rotated by this vibration of at least one of the first vibration member 16 and the second vibration member 18. Depending on the rotation direction of the rod 20, the distance between the pedicle screw 12 and the pedicle screw 14 is increased or decreased. Thus, the distance between the vertebra 24 and the vertebra 26 can be adjusted according to the growth and symptoms of the patient.

As described above, in this embodiment, the fixture 10 further includes the first vibration amplification member 28 and the second vibration amplification member 32. The first vibration amplifying member 28 and the second vibration amplifying member 32 are made of a metal having excellent biocompatibility, and are plate-like members having a length of about 10 mm, a width of about 6 mm, and a thickness of about 0.6 mm. It has a natural frequency that resonates with ultrasonic waves oscillated from outside the body. The first vibration amplifying member 28 is installed so as to be in contact with the first vibration member 16, and the second vibration amplifying member 32 is disposed so as to be in contact with the second vibration member 18. Specifically, the first vibration amplifying member 28 is placed on the first vibration member 16 and fixed from above with a rod fixture 30 so that it can vibrate on the spot. Similarly, the second vibration amplifying member 32 is placed on the second vibration member 18 and fixed from above with a rod fixture 34 so that it can vibrate on the spot. The first vibration amplifying member 28 and the second vibration amplifying member 32 are not necessarily required, and may be omitted if sufficient vibration is transmitted without them.

The first vibration amplifying member 28 transmits the vibration resonated with the ultrasonic wave oscillated from outside the body to the first vibrating member 16. Similarly, the second vibration amplifying member 32 transmits the vibration resonated with the ultrasonic wave oscillated from outside the body to the second vibrating member 18. That is, the ultrasonic wave oscillated from the outside of the body is attenuated by the human tissue 40, but the first vibration amplifying member 28 resonates with the ultrasonic wave to amplify the vibration and transmit it to the first vibrating member 16. Similarly, the second vibration amplifying member 32 resonates with ultrasonic waves, amplifies the vibration, and transmits the amplified vibration to the second vibrating member 18. The first vibration member 16 or the second vibration member 18 rotates the rod 20 by the vibration transmitted from the first vibration amplification member 28 or the second vibration amplification member 32. The mechanism by which the first vibrating member 16 and the second vibrating member 18 rotate the rod 20 will be described later.

FIG. 4 shows the first vibrating member 16. 4A is a perspective view from the left in FIG. 1, and FIG. 4B is a cross-sectional view from the left in FIG. 1 when the first vibrating member 16 is cut in parallel with the opening. As shown in FIG. 4B, the first screw 16a has four projecting portions 16j and 16k each having end portions 16e, 16f, 16g, and 16h whose distance from the central axis 16c of the first vibrating member 16 is not constant. , 16m, 16n. When the first vibrating member 16 vibrates, the protrusion 16j presses the third screw 20a to rotate the rod 20 mainly at the shortest position from the central axis 16c in the end portion 16e. The same applies to the end portions 16f, 16g, and 16h.

4B, the four protrusions 16j, 16k, 16m, and 16n have the same shape. In other words, the projecting portions 16j, 16k, 16m, and 16n and the four circular arc portions 16r, 16s, 16t, and 16u having the same shape are provided on the inner wall of the first vibrating member 16 every 45 ° along the circumferential direction. It is provided repeatedly. In addition, there is no restriction | limiting in particular in the quantity of a protrusion part. In the present embodiment, the first screw 16a includes four protrusions 16j, 16k, 16m, and 16n. However, the first screw 16a is at least a pair of protrusions that face each other in the cross-sectional diameter direction of the first vibration member 16. 16j and 16m may be provided. As in the present embodiment, the first screw 16a preferably includes at least two pairs of projecting portions 16j and 16m and projecting portions 16k and 16n that are orthogonal to each other.

Moreover, it is preferable that the end portions 16e, 16f, 16g, and 16h are oblique as in the present embodiment. This is because the vibration of the first vibrating member 16 can be efficiently converted into the rotation of the rod 20. Here, the end portion 16e is slanted in an annular cross-sectional view as shown in FIG. 4B, and is an end portion with respect to a straight line Q perpendicular to the straight line P connecting the center axis 16c and the center of the end portion 16e. It is said that 16e is diagonal. It can be similarly defined that the end portions 16f, 16g, and 16h are oblique. In FIG. 4B, the angle θ formed by the straight line Q and the end portion 16e is about 8 °. As in the present embodiment, it is preferable that all the end portions 16e, 16f, 16g, and 16h are oblique. However, unlike the present embodiment, the end portions of at least some of the protrusions of the first vibrating member 16 are It does not have to be diagonal.

FIG. 5 shows a shape change due to vibration of the first vibration member 16. FIG. 5A is a cross-sectional view of the first vibrating member 16 when it contracts in the vertical direction toward the opening due to vibration. FIG. 5B is a cross-sectional view of the first vibrating member 16 when it contracts in the left-right direction toward the opening due to vibration. In response to the ultrasonic wave oscillated from outside the body, the first vibrating member 16 vibrates in various directions.

At this time, the shape of the first vibrating member 16 changes while vibrating, and the protrusions 16j, 16k, 16m, and 16n press the rod 20 so as to rotate counterclockwise toward the opening while strongly contacting the third screw 20a. . For example, as shown in FIG. 5A, when the first vibrating member 16 vibrates and contracts in the vertical direction, the protruding portion 16j presses the position on the left side from the top of the third screw 20a in the counterclockwise direction. The protrusion 16m presses the position on the right side of the bottom of the third screw 20a in the counterclockwise direction. For this reason, the rod 20 pressed by the first vibrating member 16 rotates counterclockwise.

For example, as shown in FIG. 5B, when the first vibrating member 16 vibrates and contracts in the left-right direction, the protruding portion 16k moves counterclockwise from the right side of the third screw 20a. The protrusion 16n presses the position below the left part of the third screw 20a counterclockwise. For this reason, the rod 20 pressed by the first vibrating member 16 rotates counterclockwise. Although not shown, the second vibration member 18 similarly receives an ultrasonic wave oscillated from the outside of the body, changes its shape while vibrating, and presses the rod 20 while the protruding portion is in strong contact with the fourth screw 20b. However, since the direction of the fourth screw 20b is opposite to the direction of the third screw 20a, the rod 20 pressed by the second vibrating member 18 rotates rightward as viewed from the left in FIG.

Referring to FIGS. 1 and 6, the mechanism by which the fixture 10 extends will be described in detail. FIG. 6 shows a mechanism in which the distance between the pedicle screw 12 and the pedicle screw 14 increases, that is, the fixture 10 extends. When the fixture 10 receives ultrasonic waves from outside the body above the second vibrating member 18, the entire fixture 10 vibrates finely. Thereafter, the second vibration amplifying member 32 resonates with ultrasonic waves, and the vibration of the second vibration member 18 is particularly amplified. At this time, the second screw 18a comes into strong contact with the fourth screw 20b. And the 4th screw 20b which is a left screw rotates rightward in the direction of the arrow of FIG. 6 along the 2nd screw 18a, and the pedicle screw 14 moves to the right direction.

On the other hand, when the rod 20 rotates in the direction of the arrow in FIG. 6, the third screw 20a, which is a right screw, rotates counterclockwise along the first screw 16a, and the pedicle screw 12 moves to the left. Thus, when the second vibrating member 18 vibrates and an ultrasonic wave that rotates the rod 20 in the direction of the arrow in FIG. 6 is vibrated to the second vibrating member 18, the fixture 10 extends. In other words, what is necessary is just to set the material of the 2nd vibration member 18 and the 2nd vibration amplification member 32, a magnitude | size, etc. so that the rod 20 may rotate to the direction of the arrow of FIG.

Referring to FIG. 1 and FIG. 7, the mechanism by which the fixture 10 contracts will be described in detail. FIG. 7 shows a mechanism in which the distance between the pedicle screw 12 and the pedicle screw 14 is reduced, that is, the fixture 10 is contracted. When the fixture 10 receives ultrasonic waves from outside the body above the first vibrating member 16, the fixture 10 as a whole vibrates finely. Thereafter, the first vibration amplifying member 28 resonates with ultrasonic waves, and the vibration of the first vibration member 16 is particularly amplified. At this time, the first screw 16a comes into strong contact with the third screw 20a. And the 3rd screw 20a which is a right screw rotates in the direction of the arrow of FIG. 7 along the 1st screw 16a, and the pedicle screw 12 moves rightward.

On the other hand, when the rod 20 rotates in the direction of the arrow in FIG. 7, the fourth screw 20b, which is a left screw, rotates to the left along the second screw 18a, and the pedicle screw 14 moves to the left. In this way, when the first vibration member 16 vibrates and the ultrasonic wave that rotates the rod 20 in the direction of the arrow in FIG. In other words, the material, shape, size, and the like of the first vibration member 16 and the first vibration amplification member 28 may be set so that the rod 20 rotates in the direction of the arrow in FIG.

In addition, since the ultrasonic wave oscillated from the outside of the body is attenuated by the human tissue 40, the first vibration member 16 and the first vibration amplifying member 28 are hardly affected by the ultrasonic wave oscillated from outside the body above the second vibration member 18, for example. Does not vibrate. Even if the first vibration member 16 and the first vibration amplification member 28 vibrate, the vibration of the second vibration member 18 and the second vibration amplification member 32 is stronger, so that the rod 20 rotates as shown in FIG. The fixture 10 extends. Moreover, the rotation direction of the rod 20 can also be controlled by adjusting the frequency of ultrasonic waves, the position where the ultrasonic waves are vibrated, and the like. Moreover, although the 1st mounting part and the 2nd mounting part were each demonstrated as the vertebrae 24 and 26 in the said description, this invention can be utilized for various bones, without being limited to these.

(Second embodiment)
FIG. 8 is a cross-sectional view of the fixture 50 according to the second embodiment of the present invention. FIG. 9 is a perspective view of the fixture 50. FIG. 10 is an exploded view of the fixture 50. The fixture 50 includes a pedicle screw 12 as a first support member, a pedicle screw 14 as a second support member, a rod 52 as a first connection member having a column shape, and a second connection having a column shape. A rod 54 as a member and a vibration member 56 are provided. As in the first embodiment, the pedicle screws 12 and 14 are mounted on, for example, vertebrae 24 and 26 (first and second mounting portions), respectively. In addition, it is the same as that of 1st embodiment that a mounting part is not restricted to these places.

The rod 52 has a first screw 52a which is a right-hand thread on the outer surface of one end. The rod 52 is fixed to the pedicle screw 12 with the rod fixing tool 30 so that the one end of the rod 52 is disposed between the pedicle screw 12 and the pedicle screw 14. The rod 54 includes a second screw 54a, which is a left-hand screw opposite to the direction of the first screw 52a, on the outer surface of one end. In the present embodiment, the direction of the second screw 54a is opposite to the direction of the first screw 52a, and the shapes of the second screw 54a and the first screw 52a are symmetric.

The rod 54 is fixed to the pedicle screw 14 with the rod fixing tool 34 so that the one end of the rod 54 is disposed between the pedicle screw 12 and the pedicle screw 14. That is, between the pedicle screw 12 and the pedicle screw 14, the rod 52 is arranged such that one end of the rod 52 where the first screw 52a is formed and one end of the rod 54 where the second screw 54a is formed face each other. 52 is fixed to the pedicle screw 12, and the rod 54 is fixed to the pedicle screw 14.

The first screw 52a and the second screw 54a are screws having a special shape different from a general spiral screw. Detailed structures of the first screw 52a and the second screw 54a will be described later. The other end of the rod 52 may be a smooth surface or may be threaded so that a plurality of fixtures 50 can be connected in series. If the plurality of fixing devices 50 can be connected in series, the fixing device 50 can be applied to most of the spine 22. For this reason, the distance of the fixing tool 50 can be adjusted corresponding to each vertebra, and the spine 22 can be treated and corrected safely and efficiently.

FIG. 11 is a cross-sectional view of the vibrating member 56 divided into two in the longitudinal direction. The vibration member 56 is a nut-like member that is made of a metal having excellent biocompatibility and vibrates by receiving ultrasonic waves oscillated from outside the body. As shown in FIG. 11, the vibrating member 56 has a cylindrical shape, and a third screw 56 a that fits the first screw 52 a is formed on the inner surface of one end of the tube, and a second screw is formed on the inner surface of the other end of the tube. A fourth screw 56b that fits with 54a is provided. The third screw 56a and the fourth screw 56b are general spiral screws. The rod 52 is fitted to one end of the vibration member 56, and the rod 54 is fitted to the other end of the vibration member 56.

In addition, instead of the structure of the first screw 52a, the second screw 54a, the third screw 56a, and the fourth screw 56b of the present embodiment, one end of each of the rods 52 and 54 has a cylindrical shape. A first screw and a second screw may be formed on the inner surface, the vibration member 56 may have a column shape, and a third screw and a fourth screw may be formed on the outer surfaces of both ends of the vibration member 56, respectively. The shape of the vibrating member 56 is changed while receiving the ultrasonic wave oscillated from outside the body, and the distance between the rod 52 and the rod 54 is increased by rotating the vibrating member 56 pressed by the rods 52 and 54. Decrease.

In the present embodiment, the fixture 50 further includes a cylindrical vibration amplifying member 58. The vibration amplification member 58 is made of a metal having excellent biocompatibility, and is a tubular member having a length of about 40 mm, an outer diameter of about 8 mm, and a thickness of about 1 mm. Has a natural frequency. The vibration amplifying member 58 covers the vibration member 56 so as to come into contact with the vibration member 56. Specifically, a vibration amplification member 58 is attached to the outside of the vibration member 56.

Since the vibration amplification member 58 covers the vibration member 56, the human tissue 40 is difficult to adhere to the vibration member 56, the first screw 52a, the second screw 54a, and the like. The vibration amplifying member 58 transmits the vibration resonated with the ultrasonic wave oscillated from outside the body to the vibration member 56. That is, the ultrasonic wave oscillated from the outside of the body is attenuated by the human tissue 40, but the vibration amplifying member 58 resonates with the ultrasonic wave to amplify the vibration and transmit it to the vibrating member 56. The vibration member 56 is rotated by the vibration transmitted from the vibration amplification member 58.

FIG. 12 shows the rod 52. 12A is a perspective view from the right of FIG. 8, and FIG. 12B is a right side view. As shown in FIG. 12B, the first screw 52a includes four projecting portions 52j, 52k, 52m, and 52n having end portions 52e, 52f, 52g, and 52h, respectively. When the vibration member 56 vibrates, the third screw 56a presses the end portions 52e, 52f, 52g, and 52h of the protrusions 52j, 52k, 52m, and 52n, respectively, and the vibration member 56 rotates by the reaction.

As shown in FIG. 12B, in the present embodiment, the four projecting portions 52j, 52k, 52m, and 52n have the same shape. The protrusions 52j, 52k, 52m, and 52n are repeatedly provided at 45 ° intervals along the circumferential direction of the first screw 52a. In addition, there is no restriction | limiting in particular in the quantity of a protrusion part. In the present embodiment, the first screw 52a includes four protrusions 52j, 52k, 52m, and 52n. However, the first screw 52a is at least opposed in the diametrical direction of the cross section orthogonal to the central axis 52c of the rod 52. A pair of protrusions 52j and 52m may be provided. As in this embodiment, it is preferable that the first screw 52a includes at least two pairs of projecting portions 52j and 52m and projecting portions 52k and 52n that are orthogonal to each other.

Referring to FIGS. 8, 12, and 13, the mechanism by which the fixture 50 extends will be described in detail. FIG. 13 shows a mechanism in which the distance between the pedicle screw 12 and the pedicle screw 14 increases, that is, the fixture 50 extends. First, as shown in FIG. 13A, when the fixture 50 receives ultrasonic waves from outside the pedicle screw 12 and from outside the body, the entire fixture 50 vibrates finely. Thereafter, the vibration amplifying member 58 resonates with ultrasonic waves, and the vibration of the vibration member 56 is particularly amplified. At this time, the third screw 56a comes into strong contact with the first screw 52a, and the fourth screw 56b comes into strong contact with the second screw 52b.

Then, by the reaction, the third screw 56a is pressed against the first screw 52a and the fourth screw 56b is pressed against the second screw 52b, and the vibrating member 56 rotates in the direction of the arrow indicating the rotation in FIG. To do. That is, the third screw 56a rotates to the left with respect to the first screw 52a, which is a right screw, and the fourth screw 56b rotates to the right with respect to the second screw 54a, which is a left screw. In this way, as indicated by the arrow indicating the movement in FIG. 13B, the pedicle screw 12 moves leftward and the pedicle screw 14 moves rightward.

In other words, the material, shape, and shape of the vibration member 56, the first screw 52a, and the second screw 54, so that the vibration member 56 rotates in the direction of the arrow indicating the rotation in FIG. What is necessary is just to set a magnitude | size. Note that the vibration member 56 can be rotated in the direction opposite to the direction of the arrow indicating the rotation in FIG. 13B by adjusting the frequency of the ultrasonic wave, the position where the ultrasonic wave is vibrated, and the like. In this case, the distance between the pedicle screw 12 and the pedicle screw 14 decreases, that is, the fixture 50 contracts.

FIG. 14 shows a right side surface of a rod 62 according to a modification of the rod 52 of the second embodiment. In addition, the shape of the 1st screw 62a formed in the 1st connection member of this modification and the 2nd screw formed in the 2nd connection member is the shape of the 1st screw and 2nd screw of 2nd embodiment. Only the difference is that the other members of the fixture of the present modification are the same as the other members of the fixture of the second embodiment. In the present modification, the first screw 62 a and the second screw have shapes suitable for increasing the distance between the pedicle screw 12 and the pedicle screw 14. Since the fixation device for spinal fusion is often extended and used in the body, the rod 62 of this modification is used when it is desired to efficiently extend the fixation device without emphasizing the shrinking function of the fixation device. it can.

As shown in FIG. 14, the first screw 62a of the rod 62 has four projecting portions 62j, 62k, 62m, each having end portions 62e, 62f, 62g, 62h whose distance from the central axis 62c of the rod 62 is not constant. 62n. When the vibration member 56 vibrates, the third screw 56a strongly presses the longest position from the center shaft 62c among the end portions 62e, 62f, 62g, and 62h of the protrusions 62j, 62k, 62m, and 62n of the rod 62. As a result, the vibration member 56 rotates counterclockwise as indicated by the arrow in FIG.

As shown in FIG. 14, in this modification, the four projecting portions 62j, 62k, 62m, and 62n have the same shape. That is, the protrusions 62j, 62k, 62m, and 62n are repeatedly provided every 90 ° along the circumferential direction of the first screw 62a. The end portions 62e, 62f, 62g, and 62h may be oblique. The end 52e is slanted, as in the case of the end 16e shown in FIG. 4, that the end 62e is slanted with respect to a straight line perpendicular to the diameter passing through the center of the end 52e and the central axis 62c. . It can be similarly defined that the end portions 62f, 62g, and 62h are oblique.

In the present modification, when the vibration member 56 vibrates, the third screw 56a comes into strong contact with the predetermined position of the first screw 62a and the fourth screw contacts with the predetermined position of the second screw. Therefore, due to the reaction, the third screw 66a is strongly pressed against the first screw 52a and the fourth screw is pressed against the second screw, and the vibration member 56 rotates counterclockwise as indicated by the arrow in FIG. Cheap. Thus, the third screw 56a rotates counterclockwise with respect to the first screw 52a, which is a right-hand screw, and the fourth screw 56b rotates clockwise with respect to the second screw, which is a left-hand screw. The pedicle screw 12 moves to the left and the pedicle screw 14 moves to the right, and the fixture extends.

The present invention can take various embodiments without being limited to the embodiments described in the first and second embodiments described above. The present invention includes a support member connecting member fixed to a first support member fixed to the first mounting part and a second support member fixed to the second mounting part, and the support member connecting member is vibrated. A member and a connecting member, receiving a vibration wave oscillated from the outside, the vibrating member changes its shape while vibrating, and the vibrating member rotates due to the shape change, and the distance between the first supporting member and the second supporting member Can be viewed as a variable (increase or decrease) fixture.

Also, the present invention does not necessarily require two pairs of fitting screws (first screw and third screw, second screw and fourth screw) as shown in FIGS. In some cases, a pair of screws (first screw and third screw) that fit together may be used. In the case where only a pair of screws that are fitted to each other is used, for example, the other (portion where the second screw and the fourth screw are fitted) can be replaced with a double ring that allows only rotation.

Therefore, in one aspect of the present invention, the fixture of the present invention includes a first support member fixed to the first mounting portion, a second support member fixed to the second mounting portion, the first support member, and the first support member. A support member-to-support member coupling member fixed to the two support members, the support member-to-support member coupling member having one or a plurality of connecting members and one or a plurality of vibration members that vibrate in response to a vibration wave; At least one of the connection members and at least one of the vibration members have screws that fit together, and the vibration member that receives a vibration wave oscillated from the outside changes its shape while vibrating and is pressed by the connection member. By rotating the member, the connecting member between supporting members is configured such that the distance between the first supporting member and the second supporting member is variable.

For example, in the first embodiment shown in FIG. 1, the fixture 10 of the present invention includes a pedicle screw 12 (first support member) fixed to a vertebra 24 (first mounting portion) and a vertebra 26 (second A pedicle screw 14 (second support member) fixed to the mounting portion) and an inter-support member coupling member fixed to the pedicle screws 12 and 14, and the inter-support member coupling member includes a rod 20 (coupling member). ) And a first vibration member 16 and a second vibration member 18 (vibration member) that vibrate in response to a vibration wave, and the rod 20 (connection member) and the first vibration member 16 are screws (20a) that are fitted to each other. 16a), the shape of the first vibrating member 16 changes while receiving a vibration wave oscillated from the outside, and the rod 20 (connecting member) rotates, whereby the connecting member between the supporting members becomes pedicles. Cru 1 And the distance (first support member) and the pedicle Cru 14 (second support member) is configured so as to be variable. That is, the connecting member between support members includes the first vibration member 16, the second vibration member 18 (vibration member), and the rod 20 (connection member). And the connecting member between support members makes the distance between support members variable by a vibration wave.

Similarly, in the second embodiment shown in FIG. 8, the fixture 50 of the present invention includes a pedicle screw 12 (first support member) fixed to the vertebra 24 (first mounting portion), and the vertebra 26. A pedicle screw 14 (second support member) fixed to the (second mounting portion) and a support member connecting member fixed to the pedicle screws 12 and 14, the support member connecting member being a rod 52, 54 (connection member) and a vibration member 56 (vibration member) that vibrates in response to a vibration wave. The rods 52, 54 (connection member) and the vibration member 56 are screws (52a and 56a) that are fitted to each other. ), The shape of the vibration member 56 is changed while receiving vibration waves oscillated from the outside, and the vibration member 56 pressed by the rods 52 and 54 (connecting members) is rotated. The coupling member is Ikurusukuryu 12 a distance (first support member) and the pedicle Cru 14 (second support member) is configured so as to be variable. And the connecting member between support members makes the distance between support members variable by a vibration wave.

In the present invention, the first screw (16a, 52a) formed on the vibration member (16, 56) and the third screw (20a, 56a) formed on the connecting member (20, 52) fitted thereto are supported. It can be understood that the inter-member variable mechanism is configured. The vibration member (16, 56) changes its shape while being vibrated by the vibration wave, and the connection member (20, 52) or the vibration member pressed by the connection member (20, 52) is rotated. 20, 52) and the vibration member (16, 56) are changed to change the distance between the support members as a result. Similarly, the second screw formed on the vibration member (18, 56) and the fourth screw (20b, 54a) formed on the connecting member (20, 54) fitted to the vibration member (18, 56) serve as an inter-support member variable mechanism. It can also be seen as comprising.

The first vibration member 16 is mounted on the pedicle screw 12 fixed to the base so that the left side surface of FIG. 1 is the front surface, the first vibration amplification member 28 is further mounted on the first vibration member 16, and the upper surface is circular. The rod fixing tool 30 is attached to the pedicle screw 12, and the first vibration member 16 and the first vibration amplification member 28 are fixed to the pedicle screw 12. A commercially available bolt was fitted to the first vibrating member 16. The base was tilted so that the front of the base was inclined upward and the angle between the front of the first vibrating member 16 and the horizontal plane was about 100 °.

In this state, the tip of the oscillating portion of an ultrasonic welder (Seidensha Co., Ltd., SONOPET-302S) is brought into contact with the upper surface of the rod fixture 30, and ultrasonic waves having a frequency of 28.2 to 28.8 kHz are applied to the rod fixture A vibration was applied to 30 and the rotation direction and angular velocity of the bolt were observed using a camera. In this example, a plurality of vibration experiments were performed in which the position where the tip of the oscillating portion was in contact with the upper surface of the rod fixture 30 was changed. When the rod fixture 30 was vibrated to the right rear of the upper surface, the bolt rotated counterclockwise with an average angular velocity value of 7.02 [rad / s] and a variance value of 2.30 [(rad / s) ² ]. .

On the other hand, when the vibration is applied to the right front of the upper surface of the rod fixture 30, the average value of the angular velocity is 4.37 [rad / s], the variance is 4.42 [(rad / s) ² ], and the bolt is Rotated. Further, when the vibration is applied to the right center, which is the middle between the right back and right front of the upper surface of the rod fixture 30, the average value of the angular velocity is 2.67 [rad / s], and the variance is 1.73 [(rad / S) ² ], the bolt rotated to the right. It should be noted that when the rod fixture 30 was vibrated on the left side of the upper surface, the rotation direction of the bolt was not determined. From these results, it was also found that the rotation direction of the bolt can be controlled by adjusting the position where the ultrasonic wave is excited.

10, 50 Fixing tool 12 Pedicle screw 14 Pedicle screw 16 First vibration member 16a First screw 16c Center shafts 16e, 16f, 16g, 16h End portions 16j, 16k, 16m, 16n Protruding portions 16r, 16s, 16t, 16u Arc portion 18 Second vibration member 18a Second screw 20 Rod 20a Third screw 20b Fourth screw 22 Spine 24, 26 Vertebra 28 First vibration amplification member 30, 34 Rod fixture 32 Second vibration amplification member 40 Human tissue 52 Rod 52a First screw 52c Center shaft 52e, 52f, 52g, 52h End 52j, 52k, 52m, 52n Protruding portion 54 Rod 54a Second screw 56 Vibration member 56a Third screw 56b Fourth screw 58 Vibration amplification member 62 Rod 62c Center Shafts 62e, 62f, 62g, 62h Ends 62j, 62k, 6 m, 62n protrusion

Claims (17)

A first support member fixed to the first mounting portion;
A second support member fixed to the second mounting portion;
A first connecting member fixed to the first support member so that the first screw is provided at one end and the one end is disposed between the first support member and the second support member;
A second screw opposite to the direction of the first screw is provided at one end, and is fixed to the second support member so that the one end is disposed between the first support member and the second support member. A second connecting member;
A third screw that fits with the first screw is provided at one end, and a fourth screw that fits with the second screw at the other end. The first connecting member is at this end, and the second connecting member is at this end. A vibration member that is respectively fitted to the other end and vibrates in response to a vibration wave;
Have
The first support member is rotated by receiving the vibration wave oscillated from the outside and changing the shape of the vibration member while vibrating, and the vibration member pressed by the first connection member and the second connection member rotates. And a fixture that increases or decreases the distance between the second support member and the second support member. In claim 1,
A fixing tool used in spinal fusion in which the first mounting portion is a vertebra with a spine, the second mounting portion is another vertebra of the spine, and the outside is outside the body. In claim 1 or 2,
The first connecting member and the second connecting member have a column shape,
The first screw and the second screw are respectively formed on outer surfaces of the first connecting member and the second connecting member;
The fixture in which the vibration member has a cylindrical shape, and the third screw and the fourth screw are formed on an inner surface of the cylinder. In claim 3,
The first screw and the second screw each include a protrusion having an end portion where the distance from the central axis of the first connecting member is not constant,
The first support member is rotated by receiving the vibration wave oscillated from the outside and changing the shape of the vibration member while vibrating, and the vibration member pressed by the first connection member and the second connection member rotates. And a fixture that increases the distance between the second support member. In claim 4,
The fixing device, wherein the first screw and the second screw each include at least a pair of the protruding portions protruding in a cross-sectional diameter direction of the first connecting member and the second connecting member. In claim 5,
The fixture in which the first screw and the second screw each include two pairs of the protruding portions orthogonal to each other. In any one of Claim 1 to 6,
A fixture further comprising a vibration amplifying member that covers the vibration member so as to be in contact with the vibration member and transmits vibrations resonated by a vibration wave oscillated from the outside to the vibration member. A first support member fixed to the first mounting portion;
A second support member fixed to the second mounting portion;
A first vibration member that includes a first screw and is fixed to the first support member so as to vibrate;
A second vibration member provided with a second screw in a direction opposite to the direction of the first screw, fixed to the second support member so as to vibrate, and receiving a vibration wave to vibrate;
A third screw that engages with the first screw is provided at one end, and a fourth screw that engages with the second screw at the other end. The one end is provided on the first vibrating member, and the other end is provided on the second screw. Connecting members respectively fitted to the vibration members;
Have
Upon receiving a vibration wave oscillated from the outside, at least one of the first vibration member and the second vibration member changes its shape while being vibrated, and is pressed by at least one of the first vibration member and the second vibration member A fixture in which the distance between the first support member and the second support member increases or decreases as the connecting member rotates. In claim 8,
A fixing tool used in spinal fusion in which the first mounting portion is a vertebra with a spine, the second mounting portion is another vertebra of the spine, and the outside is outside the body. In claim 8 or 9,
The connecting member has a column shape;
The first screw and the second screw are formed on an outer surface of the connecting member;
The first vibration member has a cylindrical shape, and the third screw is formed on an inner surface of the cylinder;
The fixture in which the second vibration member has a cylindrical shape, and the fourth screw is formed on the inner surface of the cylinder. In claim 10,
The third screw includes a protrusion having an end portion where the distance from the central axis of the first vibration member is not constant,
A fixing tool, wherein the fourth screw includes a protrusion having an end portion where the distance from the central axis of the second vibrating member is not constant. In claim 11,
A fixture having an oblique end. In claim 12,
A fixture in which the third screw and the fourth screw each include at least a pair of the projecting portions facing each other in the cross-sectional diameter direction of the first vibrating member and the second vibrating member. In claim 13,
The fixture in which the third screw and the fourth screw each include two pairs of the protruding portions orthogonal to each other. In any of claims 8 to 14,
A first vibration amplifying member that is installed so as to be in contact with the first vibration member and transmits vibrations resonated with vibration waves oscillated from the outside to the first vibration member;
A second vibration amplifying member that is installed so as to be in contact with the second vibration member and transmits vibrations resonated with a vibration wave oscillated from the outside to the second vibration member;
Further having a fixture. In any one of Claims 1-15,
A fixture in which the vibration wave is an ultrasonic wave. A first support member fixed to the first mounting portion;
A second support member fixed to the second mounting portion;
A connecting member between supporting members fixed to the first supporting member and the second supporting member;
With
The support member-to-support member is
One or more connecting members;
One or more vibrating members that vibrate in response to vibration waves;
Have
At least one of the connecting members and at least one of the vibrating members includes a screw that fits together;
The shape of the vibration member is changed while receiving vibration waves oscillated from the outside, and the connection member or the vibration member pressed by the connection member rotates, whereby the support member coupling member is A fixture that allows the distance between the first support member and the second support member to be variable.

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