Treatment instrument

Abstract

This treatment instrument comprises a bone cement molding tool and a bone cement fixation tool inserted into an internal fixation tool that internally fixes bone cement filled into a vertebral body while being supported from a pedicle. The treatment instrument is configured as follows. The internal fixation tool has a through-hole in a central axis direction from the head to the tip, and can be inserted into and removed from the bone cement along the central axis thereof. The bone cement molding tool is inserted into the bone cement through the through-hole to mold a hole of a predetermined shape after the internal fixation tool is screwed into the bone cement. The bone cement fixation tool has a tip inserted into the hole molded above, and the tip is inserted into the hole through the through-hole of the internal fixation tool, thereby suppressing the rotation and / or movement in a pull-out direction of the bone cement.

Description

treatment equipment The present invention relates to a treatment instrument for manipulating a cylindrical internal fixation instrument for medical use, and is particularly suitable for use in an internal fixation operation for an affected vertebral body. Vertebroplasty and spinal fixation are known as treatments for spinal compression fractures. The spine is composed of stacked vertebral bodies and the vertebral arch, pedicle, articular process, etc. that support them. The vertebral body is a cylindrical bone that sandwiches the nucleus pulposus and the annulus fibrosus that surrounds it from above and below, and is supported by two pedicles extending from the vertebral arch. The vertebral arch is connected to the top and bottom by the upper and lower articular processes, supports the vertebral body through the pedicle, and forms the spine. Compression fracture is a disease in which the vertebral body is crushed and damaged by vertical compression. Vertebroplasty is a surgery to reconstruct the crushed vertebral body, and for example, a surgical method is used in which medical cement is filled into the vertebral body. Spinal fixation is a surgical method in which the crushed vertebral body and the healthy vertebral bodies above and below it are fixed with an instrument. Screws are screwed into the crushed vertebral body and the healthy vertebral bodies above and below it from the pedicle, and the heads of the screws are connected to rods that are crossed in the vertical direction to fix them. If symptoms are mild, vertebroplasty is used, but if symptoms are severe, spinal fusion surgery is required. A variety of screws have been proposed for use in these treatments. Patent Document 1 discloses a medical screw having a through hole in the longitudinal direction along the central axis and a side opening communicating with the through hole. An injection device such as a syringe is attached to the head of the screw, and bone cement or a physiologically activating substance is injected from the through hole through the side opening into the surrounding bone, thereby reinforcing the surrounding bone (

[0053] ~

[0057] , Figs. 6-8). Patent Document 2 discloses a medical screw that can be easily removed from the fracture site where it is screwed in. The medical screw has a hollow section formed from the head to the tip along the central axis, and a screw thread is formed on the side, and is screwed into the bone. A reverse screw thread (reverse internal thread) is provided near the inner tip of the hollow section of the screw, and it is possible to remove the screw by using a removal tool with a tip that engages with the reverse internal thread. More specifically, the removal tool is inserted from the hollow section, and the tip is engaged with the reverse internal thread of the screw to form one unit, and the removal tool is rotated to remove the screw from the body. US Publication No. 2011 / 0040337A1 JP 2016-209295 A The present inventors have found that there is a problem in that medical instruments and screws suitable for the above-mentioned procedure of combining vertebroplasty and pedicle plasty have not been sufficiently developed. The present inventor invented a treatment instrument that solves this problem and filed an international application under PCT / JP2022 / 036147. This invention is a treatment instrument integrated with a screw having a through hole along the central axis and a tappable thread on the side, and is configured so that bone cement can be injected into the affected area through the through hole of the screw with a driver connected to the head of the screw, and then the screw can be screwed into the bone cement. After injecting the bone cement, there is no need to attach the driver again, and the driver can be operated as it is, so the screw can be quickly screwed in before the bone cement hardens. On the other hand, in the conventional screw as disclosed in Patent Document 1, it is not assumed that the screw will be screwed into bone cement that has been injected in advance, but rather that after the screw is screwed in, cement or the like is injected around the screw through an opening in the side wall to reinforce the surrounding bone. Therefore, it is basically the bone that engages with the threads of the screw, and it is considered that the screw can be relatively easily removed by rotating the screw in the reverse direction. If it is expected that removal will still be difficult, a screw and removal tool designed for removal as disclosed in Patent Document 2 will be used. The inventors have further studied the risk of the screw being too tightly bitten into the bone cement and becoming unable to remove the screw, and have found that such a risk becomes apparent when the bond between the bone cement and the screw is stronger than the adhesion between the bone cement and the surrounding body tissue such as bone. In that case, they have found that using the removal tool as described in Patent Document 2 does not solve the problem. The removal tool as described in Patent Document 2 can strongly connect the screw and the driver and transmit a strong force to the screw, which helps removal when the surrounding body tissue is the patient's bone, but when the bond between the bone cement and the screw is stronger than the adhesion between the bone cement and the surrounding body tissue such as bone, as described above, there is a risk that the bone cement will separate from the surrounding body tissue instead of the screw coming out of the bone cement, and this does not help removal. In order to solve this problem, the present inventor invented an internal fixation device that is easily removable, and filed an international application under PCT / JP2023 / 022593. The internal fixation device of this invention is an alternative to the above-mentioned screw, and has a groove instead of a screw thread formed in the part that is inserted into the bone cement. When the screw thread is inserted into the bone cement, it pushes the surrounding bone cement apart while proceeding, so no gaps are formed, whereas the bone cement only penetrates into the groove due to its viscosity, so that a gap is formed, or even if no gap is formed, the adhesion with the bone cement is weak. Therefore, it can be removed with a small force. Here, the internal fixation device refers to a device that is inserted from the pedicle into the bone cement inside the vertebral body and supports and internally fixes the bone cement inside the vertebral body from the pedicle side, and is redefined as a device that includes the above-mentioned screw. The inventor has found a new problem. When inserting an internal fixation device into bone cement, it is generally screwed in using the tapping thread (at least the thread on the head side for screwing into the pedicle), but when removing the internal fixation device, it is rotated in the opposite direction to when it was screwed in. However, if the bond between the internal fixation device and the bone cement is stronger than the adhesion between the bone cement and the affected tissue such as the surrounding bone, there is a problem that the bone cement cannot be rotated and removed. An object of the present invention is to provide a treatment device that assists in the removal of an internal fixation device that is inserted from the pedicle into bone cement that has been previously filled in the vertebral body. Means for solving these problems will be described below, but other problems and novel features will become apparent from the description of this specification and the accompanying drawings. According to one embodiment of the present invention, the following is true. That is, the treatment instrument includes a bone cement molding instrument and a bone cement fixing instrument, which are inserted into an internal fixation instrument that supports and internally fixes bone cement filled in a vertebral body from the pedicle, and is configured as follows: The internal fixation instrument has a through hole in the central axis direction from the head to the tip, and can be inserted into the bone cement along its central axis and removed. The bone cement molding instrument is inserted into the bone cement through the through hole of the internal fixation instrument to mold a hole of a predetermined shape. The bone cement fixing instrument has a tip portion that is inserted into the hole molded above, and by inserting the tip portion into the hole through the through hole of the internal fixation instrument, the bone cement is suppressed from rotating and / or moving in the withdrawal direction. The effects obtained by the embodiment are briefly described below. That is, it is possible to provide a treatment device that assists in removing an internal fixation device that has been inserted from a pedicle into bone cement that has been filled in advance in a vertebral body. FIG. 1 is an explanatory diagram showing a cross-sectional structure of a treatment instrument of the present invention including a bone cement molding instrument, in order to show an example of the configuration of the treatment instrument of the present invention including a bone cement fixing instrument. FIG. 2 is an explanatory diagram showing a cross-sectional structure of a treatment instrument of the present invention including a bone cement fixing instrument, in order to show an example of the configuration of the treatment instrument of the present invention including a bone cement molding instrument. FIG. 3 is an explanatory diagram showing a bottom surface of each tip (square) seen from the proximal end side, in order to show a first example of the configuration of the bone cement molding instrument and the bone cement fixing instrument. FIG. 4 is an explanatory diagram showing a bottom surface of each tip (star) seen from the proximal end side, in order to show a third example of the configuration of the bone cement molding instrument and the bone cement fixing instrument. FIG. 5 is an explanatory diagram showing the appearance and cross-sectional structure of each tip portion seen from above, in order to show the first example of the configuration of the bone cement molding instrument and the bone cement fixing instrument. FIG. 6 is an explanatory diagram showing the bottom surface and cross-sectional structure of each tip portion seen from above, in order to show the second example of the configuration of the bone cement molding instrument and the bone cement fixing instrument. FIG. 7 is an explanatory diagram showing an example of use of the internal fixing instrument according to the present invention, in an overhead view. FIG. 8 is a top view, a front view, and a bottom view showing a configuration example of the internal fixation instrument according to the present invention. FIG. 9 is an explanatory diagram showing a cross-sectional structure in order to show a configuration example of the treatment instrument according to the present invention. FIG. 10 is an explanatory diagram showing a first half of a procedure for embedding the internal fixation instrument in a treatment using the treatment instrument of the present invention. FIG. 11 is an explanatory diagram showing a second half of an example of a procedure for embedding the internal fixation instrument in a treatment using the treatment instrument of the present invention. FIG. 12 is an explanatory diagram showing another example of a second half of a procedure for embedding the internal fixation instrument in a treatment using the treatment instrument of the present invention. FIG. 13 is an explanatory diagram showing a schematic example of a procedure for removing the internal fixation instrument in a treatment using the treatment instrument of the present invention. FIG. 14 is an explanatory diagram showing another example of a procedure for removing the internal fixation instrument in a treatment using the treatment instrument of the present invention. FIG. 15 is an explanatory diagram showing the bottom surface of each tip (cross shape) viewed from the proximal end side in order to show a fourth configuration example of the bone cement molding instrument and the bone cement fixation instrument. Fig. 16 is an explanatory diagram showing the external appearance and cross-sectional structure of the distal end of each of the bone cement molding instrument and the bone cement fixing instrument, showing a fifth configuration example of the bone cement molding instrument and the bone cement fixing instrument. Fig. 17 is an explanatory diagram showing the external appearance and cross-sectional structure of the distal end of each of the bone cement molding instrument and the bone cement fixing instrument, showing a sixth configuration example of the bone cement fixing instrument.Fig. 18 is an explanatory diagram showing a typical example of a procedure for removing an internal fixation device in a treatment using the treatment device of the third embodiment of the present invention. Fig. 19 is an explanatory diagram showing a typical example of a procedure for removing an internal fixation device in a treatment using the treatment device of the third embodiment of the present invention. Fig. 20 is an explanatory diagram showing a typical configuration example of a bone cement molding device and a driver related to the treatment device of the fourth and fifth embodiments of the present invention. Fig. 21 is an explanatory diagram showing a typical second half of a procedure for embedding an internal fixation device in a treatment using the treatment device of the fifth embodiment. Fig. 22 is an explanatory diagram showing a typical example of a procedure for removing an internal fixation device in a treatment using the treatment device of the sixth embodiment of the present invention. 1. Overview of the embodiment First, a summary of representative embodiments disclosed in the present application will be described. Reference numerals in parentheses in the summary of the representative embodiments refer only to components included in the concept of the components to which they are attached. In this specification, proximal is a medical term that refers to the side closer to the centerline of the patient's body, and distal is a medical term that refers to the farther side. Bone cement is a medical cement that contains, for example, calcium phosphate and polymethylmethacrylate as its main components and hardens over time. [1] Removal assistance device that suppresses rotation / pulling out of bone cement (Figs. 1 to 5, 15 to 17, and 20) A representative embodiment disclosed in the present application is a treatment device (100) including a bone cement molding device (50) and a bone cement fixing device (60) that are inserted into an internal fixation device (10) that supports and internally fixes bone cement filled in a vertebral body from the pedicle, and is configured as follows. The internal fixation device has a through hole (16) in the central axis direction from the head (13) to the tip, and can be inserted into and removed from the bone cement (1) along the central axis. The bone cement molding tool is inserted into the bone cement through the through hole of the internal fixation tool to mold a hole (2) of a predetermined shape. The bone cement fixing device has a tip portion (61) that is inserted into the hole, and by inserting the tip portion into the hole through the through hole of the internal fixation device and into the bone cement (1) in which the hole is formed, the bone cement is prevented from rotating around the central axis and / or moving in the pull-out direction. This makes it possible to provide a treatment instrument that assists in the removal of an internal fixation instrument that is inserted from the pedicle into bone cement that has been filled in advance within the vertebral body and that supports and internally fixes the bone cement. [2] The tapping screw of the bone cement fixation device is screwed into the circular hole to fix it (Figures 16 and 17). In the treatment instrument of [1], the tip of the bone cement molding instrument is cylindrical (Fig. 16) or tapered (Fig. 17) with a diameter decreasing toward the tip. A cylindrical or tapered hole (2) with a diameter decreasing toward the depth is formed. The bone cement fixing instrument has a screw thread that is screwed into the side wall of the hole by tapping. This allows the bone cement fixing device to suppress movement of the bone cement in both the rotational direction and the pull-out direction. [3] The bone cement molding tool also has a thread for tapping the side wall (Fig. 20) In the treatment instrument of [2], the bone cement molding instrument has a screw thread (54) that taps and screws into the side wall of the hole. This allows a hole to be formed with a pre-tapped groove in the side wall, and when it becomes necessary to remove the internal fixation device, the tapping thread of the bone cement fixation device is screwed along the pre-tapped groove in the hole, so that it can be screwed in and removed with a small force, and it is also easy to remove the bone cement fixation device after removing the internal fixation device. [4] Driver (Fig. 1, Fig. 2, Fig. 20) In [2] or [3], the treatment instrument (100) further includes a driver (20), the internal fixation instrument is connectable to the driver at a head (13), and the driver has a through hole that communicates with the through hole of the internal fixation instrument when connected to the internal fixation instrument and allows the tip portions of the bone cement molding instrument and the bone cement fixing instrument to pass through. This provides a driver (20) that can be commonly used in surgery to screw in the internal fixation device (10) and surgery to remove it. [5] The bone cement molding tool can be connected to a driver (Figure 20) In the treatment instrument of [4], the bone cement molding instrument is inserted into the through hole of the driver connected to the internal fixation instrument, and protrudes a predetermined length from the tip of the internal fixation instrument. This allows the bone cement molding tool to be inserted and a hole to be formed while the driver and internal fixation tool are connected, thereby reducing the number of steps in the procedure. [6] The bone cement molding tool and the driver are detachable (Figure 20) In the treatment instrument of [5], the bone cement molding instrument is detachably connected to the driver. This allows selective use of whether the formation of the hole and the insertion of the internal fixation device into the bone cement are performed simultaneously or separately. [7] The bone cement molding tool and the driver are integrated with a screw (Figure 20) In the treatment instrument of [6], the driver has a screw structure (53) at a distal end that can be connected to the bone cement molding instrument. This improves the maneuverability of the treating instrument when simultaneously forming the hole and inserting the internal fixation device into the bone cement. [8] The handle of the bone cement fixation device can be attached and detached (Figure 14) In the treatment instrument according to any one of [2] to [7], the bone cement fixing instrument has a structure in which the handle portion (62) and the shaft portion are removable. This allows the handle to be attached when suppressing the rotation of the bone cement fastening instrument, and the handle to be removed when removing the bone cement fastening instrument, thereby improving the degree of freedom in the procedure. [9] Guide pin (Fig. 22) In any one of items [2] to [8], the treatment device further includes a guide pin (40), and the bone cement fixing device has a through hole (64) through which the guide pin can pass. This allows the bone cement fixing device to be guided into the hole in the bone cement at the affected part along the guide pin that has been inserted into the affected part in advance.

[10] A bone cement fixing device that abuts against the side wall of a square hole to suppress the rotation of the bone cement (Figure 5) In the treatment instrument of [1], the tip of the bone cement molding instrument is a rectangular column (Fig. 5(a)) or a rectangular column tapered type (Fig. 5(b)) whose cross section becomes smaller in the direction of the tip, and a rectangular column-shaped or rectangular column tapered type hole (2) whose cross section becomes smaller in the direction of the depth is formed. The bone cement fixing instrument has a tip shape that can abut against the side wall of the hole to suppress the rotation of the bone cement. This allows the bone cement fixing tool to come into contact with the side wall of the hole and suppress the rotation of the bone cement. Since the bone cement fixing tool is simply inserted into the hole, it can be easily pulled out.

[11] The handle of the bone cement fixation device can be attached and detached (Figure 14) In the treatment instrument of

[10] , the bone cement fixing instrument has a structure in which the handle portion (62) and the shaft portion are detachable. This allows the handle to be attached when suppressing the rotation of the bone cement fastening instrument, and the handle to be removed when removing the bone cement fastening instrument, thereby improving the degree of freedom in the procedure.

[12] Driver In

[10] or

[11] , the treatment instrument further includes a driver, the internal fixation instrument is connectable to the driver at a head portion, and the driver has a through hole that communicates with the through hole of the internal fixation instrument when connected to the internal fixation instrument and allows the tip portions of the bone cement molding instrument and the bone cement fixing instrument to pass through. This provides a driver (20) that can be commonly used in surgery to screw in the internal fixation device (10) and surgery to remove it.

[13] Guide pin (Fig. 22) In any one of items

[10] to

[12] , the treatment device further includes a guide pin (40), and the bone cement fixing device has a through hole (64) through which the guide pin can pass. This allows the bone cement fixing device to be guided into the hole in the bone cement at the affected part along the guide pin that has been inserted into the affected part in advance. 2. Details of the embodiment The embodiment will now be described in further detail. [Embodiment 1] Fig. 7 is an explanatory diagram showing an example of using the internal fixation device 10 from a bird's-eye view. When a patient is in a standing position, the spine is composed of a plurality of vertebral bodies 90 stacked vertically, and Fig. 7 shows one of the vertebral bodies 90 as seen through from above and below. The vertebral body 90 is supported by a pair of left and right pedicles 91, which are connected by a vertebral arch 92. The part surrounded by the vertebral bodies 90, the pedicles 91, and the vertebral arch 92 is the spinal canal 93. A compression fracture is a disease in which a vertebral body is compressed and collapsed by a force in the vertical direction. In the treatment using the internal fixation device 10 according to the present invention, as described later with reference to Figs. 10 and 11, a space is returned to the vertebral body 90, bone cement 1 is injected, and the internal fixation device 10 is inserted (screwed) before the bone cement hardens, and the pedicle 91 side is supported. In other words, the internal fixation device 10 is inserted from the pedicle 91 into the bone cement 1 filled in the vertebral body 90 in advance, and when the bone cement 1 hardens, it is supported by the internal fixation device 10 from the pedicle 91 and fixed in the vertebral body 90. At this time, the internal fixation device 10 according to the present invention is an instrument that is screwed into the bone cement 1 in the vertebral body 90 while tapping a bone hole formed in the pedicle 91, and may be, for example, a conventional screw as described in Patent Document 1, but the tip side that is embedded in the bone cement 1 does not necessarily need to have a tapping thread. FIG. 8 is a top view (a), a front view (b), and a bottom view (c) showing a configuration example of an easily removable internal fixation device 10, which was internationally filed as PCT / JP2023 / 22593. The back view and the left and right side views are omitted because they are the same as the front view (b) except that the groove 14 and the screw thread 15 are arranged at a position extended from the front view (b). The internal fixation device 10 includes a cylindrical shaft 12 and a connection part 13 that can be connected to a driver at the distal end of the shaft 12, and the shaft 12 has a spiral groove 14 on the proximal side. As illustrated in the figure, the shaft 12 is preferably cylindrical and has a through hole 16 that penetrates from the distal end to the proximal end along the central axis. The through hole 16 can be passed through, for example, a guide pin. The through hole 16 may also be configured to be able to pass through a bone drilling instrument, a balloon catheter, a bone cement injector, or the like. The connection part 13 of the head is configured as a hexagonal column-shaped recess to engage with a hexagonal wrench so that the entire internal fixation device 10 can be rotated by engaging with a driver (not shown). In Fig. 8, a hexagonal column-shaped head (connection part) is illustrated assuming connection with a driver head having a hexagonal wrench shape, but this shape is arbitrary as long as it can transmit a rotational force, and may be changed to, for example, a star shape, a triangle, a square, a cross shape, etc. In addition, in this specification, the reference numeral 13 may be referred to as a "head" with emphasis on its position in the internal fixation device 10, or as a "connection part" with emphasis on its function of connecting with a driver. The depth of the groove 14 of the internal fixation device 10 may be uniform, but it is more preferable to make the proximal side (tip side) deeper than the distal side (head side) of the shaft 12. When the internal fixation device 10 is screwed into the bone cement 1 while rotating along the spiral of the groove 14, the proximal side (tip side) that comes into contact with the bone cement 1 first is deeper, so the bone cement 1 enters deeper into the groove 14, and as it is screwed in, it is sent along the spiral of the groove 14 to the shallower distal side (head side) of the groove 14, so that the bone cement 1 smoothly enters the groove 14 and is firmly fixed. On the other hand, when removing the internal fixation device 10, it is separated from the bone cement 1 while rotating in the opposite direction along the spiral of the groove 14, so that the force required for removal can be reduced. It is more preferable that the shaft 12 of the internal fixation device 10 has a tapered portion 17 whose diameter gradually decreases from the center toward the proximal end. When the internal fixation device 10 is screwed into the bone cement 1, the resistance when the internal fixation device 10 is first inserted into the bone cement 1 is reduced, and the force required to remove the internal fixation device 10 is also reduced. The shaft 12 of the internal fixation device 10 may be provided with a screw thread 15 on the distal side (head side). The screw thread 15 is a spiral convex portion that protrudes outward from the outer circumferential surface of the shaft 12, and has the function of tapping the surrounding bones and advancing the internal fixation device 10 (shaft 12) along the central axis as it rotates. The screw thread 15 taps the pedicle 91 and advances, firmly fixing the internal fixation device 10 and stably supporting the bone cement 1 in the vertebral body 90 into which the shaft 12 is inserted. The thread 15 and the groove 14 are preferably formed with equal leads. The lead is the distance traveled along the central axis relative to the amount of rotation of the shaft 12, and it is desirable that the distance traveled by the shaft 12 while the thread 15 taps the pedicle 91 is equal to the distance traveled by the shaft 12 along the spiral of the groove 14 when the shaft 12 is screwed into the bone cement 1. However, precise agreement is not necessarily required, and they can be intentionally made different. For example, by making the lead of the groove 14 larger than the lead of the thread 15, after the groove 14 at the tip of the shaft 12 is partially screwed into the bone cement 1 and the thread 15 starts tapping the pedicle, a force can be applied to move the bone cement 1 closer to the pedicle as the internal fixation device 10 (shaft 12) rotates. The number of threads can be different between the groove 14 and the thread 15. For example, the number of threads of the groove 14 may be smaller than the number of threads of the thread 15. This allows the bonding force between the internal fixation device 10 and the bone cement 1 to be appropriately designed while strengthening the fixation to the pedicle 91 by the thread 15. As described above, it is preferable to make the groove 14 and the thread 15 have the same lead. In this case, a new problem arises of appropriately setting the contact area with the object, but this problem is solved by designing the number of threads independently. By reducing the number of threads of the groove 14, the contact area with the bone cement 1 can be reduced, and the force required for removal can be weakened. On the other hand, by increasing the contact area between the pedicle 91 and the thread 15, the fixation of the internal fixation device 10 to the pedicle 91 can be strengthened. By optimizing the number of threads instead of the pitch, the relationship between the bone cement 1 and the groove 14 and the relationship between the pedicle 91 and the thread 15 can be independently optimized. In this specification, the term "internal fixation device" refers to a device that is inserted from the pedicle into bone cement that has been filled in the vertebral body in advance, and that is fixed from the pedicle into the vertebral body to the bone cement when the bone cement hardens. Therefore, the internal fixation device in this specification includes not only the easily removable internal fixation device 10 internationally filed as PCT / JP2023 / 022593, but also those without the groove 14, those without the thread 15, those without both the groove 14 and the thread 15, and even conventional screws with threads formed all over. Fig. 9 is an explanatory diagram showing a cross-sectional structure of a treatment instrument 100 to show a configuration example of the treatment instrument 100. Fig. 9 is drawn with the scale of the central axis direction (vertical direction on the paper) compressed and the direction along the patient's body surface (horizontal direction on the paper) emphasized. The treatment instrument 100 includes a cylindrical driver 20 that can screw the internal fixation instrument 10 into a bone, and an inner cylinder 30 that is inserted into the driver 20, and is configured as follows. The internal fixation device 10 has a blunt tip so that a soft vertebral excavation device such as a balloon can be inserted and removed, and has a screw thread 15 that can tap bone or cement on the outer wall, and a through hole 16 that can pass the inner tube 30 from the head 13 to the tip along the central axis. The driver 20 is fitted into the head 13 of the internal fixation device 10 by moving along the central axis, and is connected to the internal fixation device 10, and is configured to be able to transmit a rotational force around the central axis to the internal fixation device 10. For example, the tip of the driver 20 may be formed in the shape of a hexagonal wrench (hexagonal column), and the head 13 of the internal fixation device 10 may be formed in a hexagonal groove (recess). As described above with reference to FIG. 8, the shape of the driver tip and the shape of the screw head may be other than hexagonal, such as a star shape, as long as they are engaged with each other just by being inserted. When the driver 20 is slid along the central axis to the head of the internal fixation instrument 10, the tip of the driver 20 fits into the head 13 of the internal fixation instrument 10, making it possible to screw in the screw with the driver 20, and the screw can be easily removed by pulling out the driver 20. The inner cylinder 30 is inserted from the distal end of the driver 20 through the through holes of the driver 20 and the internal fixation device 10, and has a tip portion 32 that protrudes proximally beyond the tip of the internal fixation device 10. With the tip portion 32 protruding proximally beyond the tip of the internal fixation device 10, the inner cylinder 30 is connected and integrated with the internal fixation device 10 and the driver 20, improving operability such as screwing the internal fixation device 10. Furthermore, the integration is strengthened by inserting the guide pin 40, and the inner cylinder 30 cannot be pulled out of the internal fixation device 10 and the driver 20. An example of a structure for integrating the internal fixation device 10, the driver 20, and the inner cylinder 30 will be described. The tip 32 of the inner tube 30 is divided into a plurality of tongue pieces 31 in the direction along the central axis, and each of the plurality of tongue pieces 31 has a protrusion 33 in the direction away from the central axis. The protrusion 33 has a function of a notch that prevents the internal fixation device 10 from slipping out of the inner tube 30 as described later, so the reference numeral 33 is referred to as a notch. The plurality of tongue pieces 31 are formed, for example, by dividing the cylindrical inner tube 30 from the tip side with slits. The number of divisions is arbitrary, for example, four, six, two, three, etc. In addition, in order to provide appropriate elasticity, some processing (for example, heat treatment, processing to reduce thickness, processing to bond metal with high elasticity) may be performed. The elasticity of the tongue piece 31 is designed to have an appropriate deflection. For example, when the inner tube 30 passes through the through hole of the driver 20, the notch 33 is pressed against the inner wall of the through hole, bending in the central axis direction to allow the inner tube 30 to pass, and when the notch 33 comes out proximal to the tip of the internal fixation device 10, the bending returns to its original state and the notch 33 is caught by the tip of the internal fixation device 10. If the notch 33 has a smooth shape, even after the notch 33 comes out from the tip of the internal fixation device 10, the force for pulling the inner tube 30 can pull the notch 33 into the through hole 16 of the internal fixation device 10, and the tongue 31 can be bent again in the central axis direction, so that the inner tube 30 can be pulled out. When the guide pin 40 is inserted, it becomes impossible to bend the tongue 31 in the central axis direction, and the inner tube 30 cannot be pulled out from the internal fixation device 10 and the driver 20. Furthermore, as shown in FIG. 9, it is more preferable that the driver 20 and the inner cylinder 30 are configured so that they can be connected at the distal end. The distal end of the driver 20 is provided with a cylindrical connection part 25 having a male screw 26 thread on the outer circumferential surface, and the distal end of the inner cylinder 30 is provided with a groove-shaped connection part 35 that can accommodate the cylinder, and a female screw 36 that meshes with the male screw 26 is formed. The relationship of the projections and recesses and the relationship of the male screw and the female screw may be reversed, or other connection mechanisms may be used. Also, as exemplified in FIG. 9, it is preferable that the driver 20 is provided with a handle 27 and the inner cylinder 30 is provided with a handle 37, and that they are integrated so that they are easy to grip when connected. Even if they are connected with a screw as in this example, a latch mechanism (not shown) that prevents the connection from coming loose may be further provided. The treatment instrument 100 of the present invention includes a bone cement molding instrument 50 and a bone cement fixing instrument 60 which are inserted into an internal fixation instrument 10 that supports and internally fixes the bone cement filled in the vertebral body from the pedicle, and is configured as follows. First, the internal fixation device 10 has a through hole 16 extending in the direction of the central axis from the head 13 to the tip (proximal end), and is configured so as to be inserted into and removed from the bone cement 1 along the central axis. For an example, please refer to the above description with reference to FIG. 8. FIG. 1 is an explanatory diagram showing a cross-sectional structure of a treatment instrument 100 of the present invention including a bone cement molding instrument 50, in order to show a configuration example thereof. FIG. 1 is drawn with the scale in the central axis direction (vertical direction on the paper) compressed and the direction along the patient's body surface (horizontal direction on the paper) emphasized. The internal fixation instrument 10 and the driver 20 each have a through hole along the central axis, and are configured so that the through holes communicate with each other when they are connected. The bone cement molding instrument 50 is configured to be inserted from the distal end into the through hole that communicates when the internal fixation instrument 10 and the driver 20 are connected, and a tip portion 51 protrudes from the tip of the internal fixation instrument 10 to the proximal side. After the internal fixation instrument 10 is inserted into the bone cement 1, the bone cement molding instrument 50 is inserted into the bone cement 10 through the through hole 16 to form a hole 2 of a predetermined shape. The bone cement molding tool 50 shown in FIG. 1 includes a handle 52, but the handle does not need to be shaped because it is not important to rotate the bone cement molding tool 50, but rather to regulate the tip 51 so that it does not go too deep. The tip 51 is designed to protrude from the tip of the internal fixation tool 10 to a desired depth when the hole 2 is molded in the bone cement 1. The desired depth is arbitrary, for example, about 1 cm. To indicate the amount of protrusion, a scale can be engraved or printed on the distal end side of the shaft of the bone cement molding tool 50, and a stopper with a diameter larger than the through hole of the driver 20 can be provided to prevent excessive protrusion. The position where the handle 52 is attached can also be adjusted to function as this stopper. Alternatively, if the bone cement molding tool 50 is structured to be connected to the driver 20 by a screw or the like, the internal fixation tool 10 can be screwed into the bone cement while simultaneously molding the hole 2. The depth of the hole 2 may not be controlled solely by the bone cement molding instrument 50, but may be naturally molded to a predetermined depth (for example, 1 cm deeper than the tip of the internal fixation instrument 10) once the internal fixation instrument 10 is inserted to an assumed depth based on its length. FIG. 2 is an explanatory diagram showing a cross-sectional structure of a medical instrument including a bone cement fixing instrument 60 according to the present invention. As in FIG. 1, the scale in the central axis direction (vertical direction on the paper) is compressed, and the direction along the patient's body surface (horizontal direction on the paper) is emphasized. As in the bone cement molding instrument 50, the bone cement fixing instrument 60 is inserted from the distal end into a through hole that communicates when the internal fixation instrument 10 and the driver 20 are connected, and a tip portion 61 is configured to protrude from the tip of the internal fixation instrument 10 to the proximal side. The communicating through hole has a circular cross section, and the inserted bone cement fixing instrument 60 also has a circular cross section, and is configured so that the mutual rotational movements do not interfere with each other. In simple terms, the bone cement fixing instrument 60 does not rotate even when the driver 20 is rotated. The bone cement fixing instrument 60 has a tip portion 61 that is inserted into the hole 2 formed by the bone cement molding instrument 50. The tip 61 has, for example, the same shape as the above-mentioned predetermined shape, and is inserted through the through hole 16 of the internal fixation device 10 into the bone cement 1 in which the hole 2 is formed, and the tip 61 is inserted into the hole 2 to suppress the rotation of the bone cement 1 around the central axis. Here, "the same shape" does not mean that the size is the same without error, but it is sufficient that the tip 61 of the bone cement fixation device 60 fits into the hole 2 formed by the tip 51 of the bone cement molding device 50 to inhibit the rotation of the bone cement 1, and it is preferable that a sufficient amount of slack is allowed for smooth insertion. This is the same throughout this specification. Since the tip 61 of the bone cement fixation device 60 only needs to fit into the hole 2 formed by the tip 51 of the bone cement molding device 50, "the same shape" is a sufficient condition but not a necessary condition, and various shapes can be adopted as described later. Furthermore, when the tip 61 of the bone cement fixing instrument 60 is fitted into the hole 2 formed by the tip 51 of the bone cement molding instrument 50, the tip abuts against the bottom of the hole 2, thereby suppressing movement in the direction of pulling out the bone cement 1. This makes it possible to provide a treatment instrument that assists in removing an internal fixation instrument that is inserted from the pedicle into the bone cement 10 that has been filled in advance in the vertebral body. It is more preferable that the bone cement fixing tool 60 has a handle 62 at the distal end. As described above, the driver 20 and the inserted bone cement fixing tool 60 are configured so that their rotational movements do not interfere with each other, so that when the driver 20 is rotated, the bone cement fixing tool 60 can be held down by the handle 62 so that it does not rotate together. In addition, the handle 62 may be configured to be detachable, as described later. In Fig. 2, the handle 62 is in contact with the distal end of the driver 20 with the tip 61 of the bone cement fixation tool 60 protruding slightly from the tip of the internal fixation tool 10, but in reality, the length of the bone cement fixation tool 60 is longer than the illustrated example. As will be described later with reference to Fig. 13, with the tip 61 of the bone cement fixation tool 60 inserted into the hole 2 of the bone cement 1, the handle 62 is provided at a position away in the distal direction in order to remove the internal fixation tool 10 (see Figs. 13

[0024] and

[0025] ). A scale indicating how much the tip 61 of the bone cement fixation tool 60 protrudes from the tip of the internal fixation tool 10 with the driver 20 and the internal fixation tool 10 connected may be provided on the distal side of the bone cement fixation tool 60. When the bone cement fixing device 60 is inserted into the internal fixation device 10 before removal, the insertion of the bone cement fixing device 60 stops within the hole 2 formed in the bone cement 1, but in the unlikely event that the bone cement 1 is damaged and does not stop within the hole 2, it is possible to call attention not to injure the surrounding body tissue by inserting a length beyond the expected length. Also, a stopper mechanism may be provided to prevent the device from being inserted too deeply. The shapes of the tip portion 51 of the bone cement molding instrument 50 and the tip portion 61 of the bone cement fixing instrument 60 will be described in more detail. For example, the "predetermined shape" is preferably a prismatic shape. 3 and 5 are explanatory diagrams showing the distal ends of the bone cement molding instrument 50 and the bone cement fixing instrument 60 ((a) shows the distal end 51 of the bone cement molding instrument 50, and (b) shows the distal end 61 of the bone cement fixing instrument 60) to show examples of the configuration of the instrument. FIG. 3 shows the bottom surface as viewed from the proximal end side, and FIG. 5 shows the appearance and cross-sectional structure of the distal ends of the instruments from above. As an example, the bone cement molding instrument 50 has a cylindrical shaft and a rectangular prism-shaped distal end 51, and the bone cement fixing instrument 60 has a cylindrical shaft and a rectangular prism-shaped distal end 61. As shown in the figures, it is more preferable that the distal end 61 of the bone cement fixing instrument 60 has a quadrangular pyramid portion at the end of the quadrangular prism, since this allows for smooth insertion. The diameter d50 of the cylindrical shaft of the bone cement molding instrument 50 is slightly smaller than the diameter d10 of the through hole 16 of the bone cement 10, and the quadrangular prism of the distal end 51 is formed inside it. For example, the length d51 of the diagonal of the square of the cross section of the regular rectangular prism is equal to or smaller than d50. The bone cement fixing instrument 60 has a cylindrical shaft and a rectangular prism-shaped tip 61. The diameter d60 of the cylindrical shaft of the bone cement fixing instrument 60 is slightly smaller than the diameter d10 of the through hole 16 of the bone cement 10, and the rectangular prism of the tip 61 is formed inside it. For example, the length d61 of the diagonal of the square of the cross section of the regular rectangular prism is equal to or smaller than d51, and is preferably set to a size that fits almost snugly into the hole 2 formed by the tip 51 of the bone cement molding instrument 50. It is sufficient that the bone cement 1 is prevented from rotating by fitting in it, so it is acceptable for there to be some leeway rather than fitting in snugly. Thereby, the bone cement fixing device 60 can suppress the rotation of the bone cement 1 simply by inserting it into the hole formed in the bone cement 1 . Although a quadrangular prism has been described as an example, other shapes may be used. Triangular, pentagonal, or hexagonal prisms may be used, and any shapes such as star, plate, or cross plate may be used. It is sufficient that the bone cement molding instrument 50 and the bone cement fixing instrument 60 have tip portions of the same shape, and the tip portion 61 of the bone cement fixing instrument 60 fits into the hole 2 formed by the bone cement molding instrument 50 to suppress the movement in the rotational direction. Fig. 4 is an explanatory diagram showing the bottom surface of each tip portion (star shape) viewed from the proximal end side to show another configuration example of the bone cement molding instrument 50 and the bone cement fixing instrument 60. 5 shows an example in which the bone cement molding instrument 50 and the bone cement fixing instrument 60 have the same rectangular prism-shaped tip and fit snugly together to restrict the rotational movement. As shown in the cross-sectional structure of FIG. 5(c), the tip of the bone cement fixing instrument 60 hits the bottom of the hole 2, so that the movement in the direction in which the bone cement 1 is pulled out is also restricted, but it is understood that the restriction of rotation is the main restriction. 6 is an explanatory diagram showing the bottom view and cross-sectional structure of the tip of each of the bone cement molding instrument 50 and the bone cement fixing instrument 60 in order to show another configuration example of the bone cement molding instrument 50 and the bone cement fixing instrument 60. The tip 51 of the bone cement molding instrument 50 and the tip 61 of the bone cement fixing instrument 60 are each a rectangular column tapered type with a quadrangular pyramid formed at the end of a quadrangular column. The tip 51 of the bone cement molding instrument 50 has an acute angle more acute than the tip 61 of the bone cement fixing instrument 60, and as shown in the cross-sectional structure of FIG. 6(c), the tip 61 of the bone cement fixing instrument 60 is structured to abut and fit into the side wall of the hole 2 formed by the tip 51 of the bone cement molding instrument 50 before reaching the bottom of the hole 2. This suppresses both the movement in the rotation direction and the movement in the pull-out direction. In Figures 5 and 6, the tip of the awl is depicted as sharp to aid in understanding, but it is preferable that the tip be blunted so as not to damage parts of body tissue, nerves or blood vessels. Furthermore, as described later in embodiments 2 and 3, the tip 61 of the bone cement fixing instrument 60 does not need to have the same shape as the tip 51 of the bone cement molding instrument 50, but it is sufficient if it can fit into the hole 2 formed in the bone cement 1 by the bone cement molding instrument 50 and suppress the rotation of the bone cement 1. A surgical procedure using the treatment instrument 100 of the present invention will now be described. 10 and 11 are explanatory diagrams that show a procedure for embedding the internal fixation device 10 in a treatment using the treatment device 100, with FIG. 10 showing the first half of the procedure and FIG. 11 showing the second half. Although FIG. 10 and FIG. 11 show vertebroplasty, the method of inserting the internal fixation device 10 into a vertebral body is similar to that of spinal fixation and vertebral body reinforcement surgery in artificial disc replacement (not shown). FIG. 10 and FIG. 11 show a schematic cross section of the affected part of a patient, from the outside of the skin 94 through the pedicle 91 to the vertebral body 90, with the upper side being the distal side and the lower side being the proximal side. The scale of the central axis direction (vertical direction on the page) is compressed, and the direction along the patient's body surface (horizontal direction on the page) is emphasized. The pedicle 91 is located on both the left and right sides of the vertebral body 90, so the same treatment is performed on one vertebral body 90 from the left and right, but FIG. 10 and FIG. 11 show one of them. First step ([1]): The subcutaneous tissue from the skin 94 on the surface of the patient's back to the affected vertebral body 90 is incised and perforated, and a guide pin 40 is inserted through the pedicle 91 to the vertebral body 90. Second step ([2]): The internal fixation device 10 and the driver 20 are connected, and the inner tube 30 is inserted into the through-hole on the inside thereof so that the tip portion 32 protrudes from the tip of the internal fixation device 10. The inner tube 30 is then placed over the guide pin 40, and the driver 20 is inserted into the patient's body along the guide pin 40. Third step ([3]): The treatment instrument 100, in which the internal fixation device 10, the driver 20, and the inner cylinder 30 are connected and integrated, is further pushed in the proximal direction along the guide pin 40, and the tips of the inner cylinder 30 and the internal fixation device 10 are screwed into the pedicle 91. Fourth step ([4]): After the tip of the internal fixation device 10 is screwed in until it reaches the vicinity of the entrance of the vertebral body 90, the guide pin 40 is removed. At this time, the notch 33 of the inner tube 30 contacts the tip of the internal fixation device 10 and prevents the inner tube 30 from being naturally removed, but by removing the guide pin 40, the tongue piece 31 is bent in the central axis direction by the force of removing the inner tube 30, and the inner tube 30 can be removed. Fifth step ([5]): The inner cylinder 30 is removed. At this time, the driver 20 is simply inserted into the head 13 of the internal fixation device 10, so it is held down so as not to come out. Although not shown in the figure, in this step, if necessary, a vertebral body excavation device may be introduced through the driver 20 and the through-hole of the internal fixation device 10 to excavate the inside of the vertebral body 90 in order to fill the vertebral body with cement for reinforcement. Sixth step ([6]): The balloon catheter 70 is introduced into the vertebral body 90 through the through-hole of the driver 20 and the through-hole of the internal fixation device 10, and the balloon 71 is inflated inside the vertebral body 90. For example, the balloon 71 is inflated by injecting a contrast agent through the balloon catheter 70 and applying pressure. The purpose is to return the vertebral body 90 to its original size when the vertebral body 90 has a compression fracture due to osteoporosis or the like. Seventh step ([7]): The balloon catheter 70 is pulled out from the through-hole of the driver 20 and the internal fixation device 10, and the cement injector 80 is inserted to inject the bone cement 1 into the vertebral body 90. For example, if the volume of cement that can be filled at one time by the cement injector 80 is about 1.5 ml, in the case of vertebroplasty for a fracture, the cement is repeatedly pumped about three times from each side, a total of six to seven times, to fill about 10 ml of bone cement 1 into the vertebral body 90. When applied to spinal fixation surgery and vertebral reinforcement surgery in artificial disc replacement surgery other than vertebroplasty, the amount of cement filled is adjusted according to the condition of the bone. Eighth step ([8]): The cement injector 80 is pulled out from the driver 20 and the through hole of the internal fixation device 10. Ninth step ([9]): Using the driver 20, the internal fixation device 10 is screwed into the filled bone cement 1. Tenth step (

[0010] ): The bone cement molding tool 50 is inserted into the bone cement 1 through the through hole of the driver 20 and the through hole of the internal fixation device 10. The bone cement 1 has not yet hardened, and the tip 51 of the bone cement molding tool 50 molds a hole 2 of a predetermined shape. Eleventh step (

[0011] ): The bone cement molding instrument 50 and the driver 20 are removed, and the incised skin 94 is sutured to complete the treatment. As described above, in the procedure of embedding the bone cement 1 and internally fixing it with the internal fixation device 10, it is an important part of the present invention that the hole 2 of a predetermined shape is formed in the bone cement 1 that has not yet hardened by the tip 51 of the bone cement molding device 50. Note that the procedure of embedding the internal fixation device described here with reference to Figures 10 and 11 is only one example. For the second step ([2]) to the sixth step ([6]), for example, a procedure may be adopted in which, at the stage where a balloon is inserted through another outer cylinder to secure a space for filling the bone cement 1, a thick guide pin is inserted, the outer cylinder is removed, and the internal fixation device 10 and the driver 20 are inserted. 12 is an explanatory diagram showing a schematic diagram of another example of the latter half of the procedure for embedding an internal fixation device in a treatment using the treatment device of the present invention. The first half (first to sixth steps) through the seventh step are the same as those described above with reference to FIGS. 10 and 11. Eighth step ([8']): The cement injector 80 is pulled out from the driver 20 and the through-hole of the internal fixation device 10, and the bone cement molding tool 50 is inserted. The tip 51 of the bone cement molding tool 50 molds the hole 2 of a predetermined shape in the bone cement 1. Ninth step ([9']): Using the driver 20, the internal fixation device 10 is screwed into the filled bone cement 1. Tenth step ([10']): The bone cement molding tool 50 is pulled out. The bone cement 1 has a hole 2 of a predetermined shape molded therein. Eleventh step (

[0011] ): The driver 20 is withdrawn (actually, together with the withdrawal of the bone cement molding instrument 50 in the tenth step ([10'])), and the incised skin 94 is sutured to complete the treatment. In this way, the hole 2 of a predetermined shape may be formed in the bone cement 1 by the bone cement molding tool 50 either before or after the internal fixation tool 10 is inserted into the bone cement 1 using the driver 20. According to the procedure of Fig. 11, the hole 2 is formed by the bone cement molding tool 50 after the internal fixation tool 1 is inserted into the bone cement 1, so that the positional deviation between the through hole 16 of the internal fixation tool 1 and the hole 2 is minimized. On the other hand, in the procedure of Fig. 12, the hole 2 is formed by the bone cement molding tool 50 before the hardening of the bone cement 1 progresses, and then the internal fixation tool 1 can be inserted continuously. Next, a procedure for removing the internal fixation device 10 will be described. FIG. 13 is an explanatory diagram that illustrates an example of a procedure for removing the internal fixation device 10 during treatment using the treatment device of the present invention. Initial state (

[0021] ): Bone cement 1 is internally fixed to a patient's vertebral body 90 by being supported by an internal fixation device 10 inserted from a pedicle 91. A hole 2 of a predetermined shape is formed in the bone cement 1 through a through hole 16 of the internal fixation device 10. First step (

[0022] ): The subcutaneous tissue from the skin 94, which is the body surface of the patient's back, to the vertebral body 90, which is the affected area, is incised and perforated, and a guide pin 40 is inserted into the through hole 16 of the internal fixation device 10 inserted into the pedicle 91.

[0022] in Fig. 13 illustrates an example in which the guide pin 40 is introduced up to the hole 2 formed in the bone cement 1 in the vertebral body 90, but it is sufficient that the guide pin 40 reaches the through hole 16 of the internal fixation device 10. Second step (

[0023] ): By aligning the through hole of the driver 20 with the inserted guide pin 40, the driver 20 is guided to the internal fixation device 10, and the tip of the driver 20 is fitted into the head (connection part) 13 of the internal fixation device 10 to connect it. Third step (

[0024] ): The bone cement fixation instrument 60 is inserted into the through hole of the driver 20 and the through hole 16 of the internal fixation instrument 10, which are connected by the connection between the driver 20 and the internal fixation instrument 10, and guided into the vertebral body 90, and the tip 61 is inserted into the hole 2 of the bone cement 1. The shape of the tip 61 of the bone cement fixation instrument 60 and the shape of the hole 2 of the bone cement 1 are the same, so that they can fit together and movement in the rotational direction is suppressed. Note that movement in the direction of pulling out the bone cement 1 is suppressed by the tip of the bone cement fixation instrument 60 abutting the bottom of the hole 2. Fourth step (

[0025] ): With the tip 61 of the bone cement fixing device 60 fitted in the hole 2 of the bone cement 1 and the movement in the direction of rotation and removal being restricted, the internal fixation device 10 is removed by rotating the driver 20 while holding the bone cement fixing device 60 with the handle 62 so as not to rotate. If the screw thread 15 provided on the distal side of the internal fixation device 10 taps the pedicle 91 during insertion, a propulsive force in the direction of removal can be applied to the internal fixation device 10 by rotating it in the opposite direction to that during insertion, and the internal fixation device 10 can be smoothly removed. Alternatively, if the internal fixation device 10 does not have a screw thread or the like, it is possible to knock up and remove the internal fixation device 10 using an instrument such as the driver 20 or forceps for holding the internal fixation device 10 while restricting the movement of the bone cement 1 in the direction of removal with the bone cement fixing device 60. Fifth step (

[0026] ): The bone cement fixing device 60 is removed (actually, together with the internal fixation device 10 and driver 20 in the fourth step (

[0025] )) and the incised skin 94 is sutured to complete the treatment. If the tip of the bone cement fixing device 60 and the shape of the hole 2 are both rectangular columns, for example, it can be removed by simply pulling it out. FIG. 14 is an explanatory diagram that illustrates another example of the procedure for removing the internal fixation device 10. In FIG. Initial state (

[0031] ): As in the initial state (

[0021] ) shown in Fig. 13, bone cement 1 is supported by an internal fixation device 10 inserted from a pedicle 91 and is internally fixed to a patient's vertebral body 90. A hole 2 of a predetermined shape is formed in the bone cement 1 through a through hole 16 of the internal fixation device 10. First step (

[0032] ): The subcutaneous tissue from the skin 94, which is the body surface of the patient's back, to the vertebral body 90, which is the affected area, is incised and perforated, and instead of the guide pin 40 shown in

[0022] of FIG. 13, the bone cement fixation device 60 is directly inserted into the through hole 16 of the internal fixation device 10. More specifically, the tip of the bone cement fixation device 60 inserted into the through hole of the driver 20 is introduced into the through hole 16 of the internal fixation device 10 inserted into the pedicle 91. It is more preferable that the handle 62 of the bone cement fixation device 60 is configured to be detachable. With the handle 62 removed, the bone cement fixation device 60 is inserted into the through hole 16 of the internal fixation device 10 in the same manner as the guide pin 40, and the driver 20 can be guided from the distal end of the bone cement fixation device 60 to the internal fixation device 10 along the shaft of the bone cement fixation device 60 and connected to the head (connection part) 13 of the internal fixation device 10. Second step (

[0033] ): The driver 20 is pushed deeply along the bone cement fixing device 60, and connected to the head (connecting portion) 13 of the internal fixation device 10. The bone cement fixing device 60 is inserted even deeper, and the tip 61 of the bone cement fixing device 60 is inserted into the hole 2 of the bone cement 1. The driver 20 and the bone cement fixing device 60 may be inserted in any order, and may be inserted simultaneously in parallel in either order. The tip 61 of the bone cement fixing device 60 and the hole 2 of the bone cement 1 are machined to the same shape, and the fit between them suppresses movement in the rotational direction. Note that movement in the direction of pulling out the bone cement 1 is suppressed by the tip of the bone cement fixing device 60 abutting the bottom of the hole 2. Third step (

[0034] ): With the tip 61 of the bone cement fixing device 60 fitted into the hole 2 of the bone cement 1 and the movement in the direction of rotation and removal being restricted, the internal fixation device 10 is removed by rotating the driver 20 while holding the bone cement fixing device 60 with the handle 62 so as not to rotate. If the screw thread 15 provided on the distal side of the internal fixation device 10 taps the pedicle 91 during insertion, a propulsive force in the direction of removal can be applied to the internal fixation device 10 by rotating it in the opposite direction to that during insertion, and the internal fixation device 10 can be smoothly removed. Alternatively, if the internal fixation device 10 does not have a screw thread or the like, it is possible to knock up and remove the internal fixation device 10 using an instrument such as the driver 20 or forceps for holding the internal fixation device 10 while restricting the movement of the bone cement 1 in the direction of removal with the bone cement fixing device 60. Fourth step (

[0035] ): Remove the handle 62 from the bone cement fixation instrument 60, and remove the removed internal fixation instrument 10 and driver 20. Fifth step (

[0036] ): The bone cement fixing instrument 60 is removed, and the incised skin 94 is sutured to complete the treatment. If the tip 61 of the bone cement fixing instrument 60 is tightly bitten into the hole 2 of the bone cement 1, the handle 62 is attached and the instrument is removed. However, if the instrument is simply stuck, the bone cement fixing instrument 60, the internal fixation instrument 10, and the driver 20 may be removed simultaneously and integrally, rather than removing the internal fixation instrument 10 and the driver 20 in advance in the fourth step (

[0035] ). The third step (

[0034] ) and the fourth step (

[0035] ) are the same as the fourth step (

[0025] ) and the fifth step (

[0026] ) in the example shown in Fig. 13. In the first step, the bone cement fixing device 60 is directly inserted into the internal fixation device 10 to be removed without using the guide pin 40, so that the number of steps can be reduced. In this procedure, the procedure has been described on the assumption that a screw thread or groove is formed at the tip of the internal fixation device 10, and the internal fixation device 10 is inserted into and removed from the bone cement 1 by rotating and counter-rotating the screw. However, this procedure can also be applied to a case where a screw thread or the like is not formed at the tip of the internal fixation device 10, and the internal fixation device 10 is inserted into and removed from the bone cement 1 by simply pushing and pulling. In that case, the bone cement fixation device 60 restrains the movement in the pulling direction, which is the same as the direction in which the internal fixation device 10 is pulled, rather than restraining the movement of the bone cement 1 in the rotational direction. [Embodiment 2] In the first embodiment, the solution principle is to mold a hole 2 of a predetermined shape in the bone cement 1 in advance with the tip 51 of the bone cement molding instrument 50, and then fit the tip 61 of the bone cement fixing instrument 60 of the same shape to suppress the rotation of the bone cement 1. However, the tip 61 of the bone cement fixing instrument 60 does not necessarily have to have the same shape as the tip 51 of the bone cement molding instrument 50, and it is sufficient that the tip 61 fits into the hole 2 formed by using the tip 51 of the bone cement molding instrument 50 to suppress the rotation of the bone cement 1. 15 is an explanatory diagram showing the tip of each of the bone cement molding instrument 50 and the bone cement fixing instrument 60, which are examples of the treatment instrument according to the second embodiment of the present invention, to show an example of the configuration, and shows the bottom surface as viewed from the proximal end side (bottom side). (a) is the tip 51 of the bone cement molding instrument 50. It has the same shape as the bone cement molding instrument 50 of the first embodiment shown in FIG. 3, and has a cylindrical shaft and a rectangular prism tip 51, and the bone cement fixing instrument 60 has a cylindrical shaft and a rectangular prism tip 61. The diameter d50 of the cylindrical shaft of the bone cement molding instrument 50 is slightly smaller than the diameter d10 of the through hole 16 of the bone cement 10, and the rectangular prism of the tip 51 is formed inside it. For example, the length d51 of the diagonal of the square of the cross section of the regular rectangular prism is equal to or smaller than d50. 1B shows the tip 61 of the bone cement fixing instrument 60. The bone cement fixing instrument 60 has a cylindrical shaft and a columnar tip 61 with a cross-shaped cross section. The diameter d60 of the cylindrical shaft of the bone cement fixing instrument 60 is slightly smaller than the diameter d10 of the through hole 16 of the bone cement 10, and the tip 61 is formed inside the diameter d60. For example, the width d61 of the cross-shaped cross section is preferably equal to or smaller than d51 and is a size that fits almost snugly into the hole 2 formed by the tip 51 of the bone cement molding instrument 50. It is sufficient that the bone cement 1 is prevented from rotating by fitting in the cross-shaped shaft, so it is acceptable for the tip 61 to have some leeway rather than fitting snugly. 15 shows an example of a square prism and a cross shape, but a straight line shape that fits into the diagonal of a square prism may also be used. There are many other variations, such as a hexagonal prism for the tip 51 of the bone cement molding instrument 50, a triangular prism for the tip 61 of the bone cement fixing instrument 60, or a tapered tip for the cross. [Embodiment 3] A further modified example will be described. In this case, the tip 51 of the bone cement molding tool 50 is cylindrical. For example, when the internal fixation tool 10 is to be embedded in the vertebral body, a special bone cement molding tool 50 may not be available, and a guide pin or a cylindrical bone cement injector or cement pusher may be used instead to form the hole 2. Since the hole 2 is circular, there is no option for the shape of the tip 61 of the bone cement fixing tool 60 that would enable the bone cement 1 to be prevented from rotating by simply fitting it in. 16A and 16B are explanatory diagrams showing the external appearance of the distal end portions of a bone cement molding instrument 50 and a bone cement fixing instrument 60, which are examples of the treatment instrument according to the third embodiment of the present invention, in order to show an example of the configuration. The distal end portion 51 of the bone cement molding instrument 50 is cylindrical as shown in FIG. 16A. The distal end portion 61 of the bone cement fixing instrument 60 has a thread that is tapped and inserted into the hole 2 formed by the distal end portion 51 of the bone cement molding instrument 50, and a blunt tip that comes into contact with the bottom of the hole 2 and stops the insertion, as shown in FIG. 16B. More specifically, the outer periphery of the cylindrical portion of the distal end portion 61 of the bone cement fixing instrument 60 is smaller than the diameter of the hole 2, and the diameter of the outer periphery that follows the apex of the tapping thread is equal to or larger than the diameter of the hole 2. Theoretically, this diameter needs to be larger than the diameter of hole 2 for tapping, but in reality, it is possible that the bone cement 1 may not have hardened sufficiently at the time hole 2 is molded, and hole 2 may become smaller after the bone cement molding instrument 50 is removed. Therefore, it should be considered that the outer diameter of the outer periphery tracing the apex of the tapping thread at the tip 61 of the bone cement fixing instrument 60 should be made equal to the diameter of hole 2. This makes it possible to provide another bone cement fixing device 60 that can suppress the rotation of the bone cement 1. For example, by forming a hole 2 in the bone cement 1 using the guide pin 40 or the bone cement injector 80 as an example of the bone cement molding device 50, and providing a tapping screw thread having an outer diameter equal to or larger than the thickness of the guide pin 40 at the tip 61 of the bone cement fixing device 60, the internal fixation device 10 can be rotated in the reverse direction by operating the driver 20 and removed in a state in which the bone cement 1 is fixed by screwing the bone cement fixing device 60. Fig. 17 is an explanatory diagram showing the appearance and cross-sectional structure of the distal end of each of the bone cement molding instrument 50 and the bone cement fixing instrument 60 in order to show another configuration example of the bone cement molding instrument 50 and the bone cement fixing instrument 60. While the distal end 51 of the bone cement molding instrument 50 and the distal end 61 of the bone cement fixing instrument 60 shown in Fig. 16 are each cylindrical, in the example shown in Fig. 17, the distal end 51 of the bone cement molding instrument 50 and the distal end 61 of the bone cement fixing instrument 60 are each cylindrical tapered. The cylindrical tapered shape is a shape having a side surface inclined so that the diameter becomes smaller toward the distal end, and may be a truncated cone or a cone as shown in the figure. The outer peripheral surface of the distal end 51 of the bone cement molding instrument 50 is smooth, and the outer peripheral surface of the distal end 61 of the bone cement fixing instrument 60 is formed with a thread for tapping. As shown in (c), the hole 2 molded by the tip 51 of the bone cement molding instrument 50 narrows toward the bottom, so that the tapping thread formed on the outer periphery of the tip 61 of the bone cement fixing instrument 60 is screwed into the side wall of the hole 2, and the tip 61 of the bone cement fixing instrument 60 fits into the hole 2 and stops before the tip of the tip 61 reaches the bottom of the hole 2. The bone cement fixing instrument 60 can suppress the forces of the bone cement 1 in the rotational and pull-out directions. 17, the diameter of the bottom surface (the side contacting the shaft) of each of the tip portion 51 of the bone cement molding instrument 50 and the tip portion 61 of the bone cement fixing instrument 60 is drawn to be smaller than that of the shaft, but this may be the same diameter as the shaft. However, the diameter of the outer periphery of the thread formed on the tip portion 61 of the bone cement fixing instrument 60 needs to be smaller than the diameter of the through hole 16 of the internal fixation instrument 10. FIG. 18 is an explanatory diagram that illustrates an example of a procedure for removing the internal fixation device 10 during treatment using the treatment device of the third embodiment. Initial state (

[0041] ): Bone cement 1 is supported by an internal fixation device 10 inserted from a pedicle 91 and is thereby internally fixed in a vertebral body 90 of a patient. A hole 2 is formed in the bone cement 1 through a through-hole 16 of the internal fixation device 10. In Fig. 18, the hole 2 is assumed to be a cylindrical hole formed by a cylinder, but as described above, the same applies if the hole is a tapered cylinder (frustum or cone) instead of a cylinder. First step (

[0042] ): The subcutaneous tissue from the skin 94, which is the body surface of the patient's back, to the vertebral body 90, which is the affected area, is incised and perforated, and the guide pin 40 is introduced into the through hole 16 of the internal fixation device 10 inserted into the pedicle 91.

[0042] in Figure 18 illustrates an example in which the guide pin 40 is introduced up to the hole 2 formed in the bone cement 1 in the vertebral body 90, but it is sufficient if the guide pin 40 reaches the through hole 16 of the internal fixation device 10. Second step (

[0043] ): By aligning the through hole of the driver 20 with the inserted guide pin 40, the driver 20 is guided to the internal fixation device 10, and the tip of the driver 20 is fitted into the head (connection part) 13 of the internal fixation device 10 to connect it. Third step (

[0044] ): The bone cement fixing device 60 is inserted into the through hole 16 of the internal fixation device 10 and the through hole 2 of the driver 20, which are connected by the connection between the driver 20 and the internal fixation device 10, and guided into the vertebral body 90, and the tip 61 is inserted into the hole 2 of the bone cement 1. The tip 61 of the bone cement fixing device 60 is provided with a thread for tapping, so it advances while tapping into the hole 2 of the bone cement 1, and stops when the tip of the tip 61 reaches the bottom of the hole 2. Thereafter, tapping is continued while holding the driver 20 so that the bone cement 1 does not rotate. A force is generated by tapping that removes the internal fixation device 10 in a direction opposite to the force rotating the bone cement 1, and a gap is created between the internal fixation device 10 and the bone cement 1, making it possible to remove the internal fixation device 10. Fourth step (

[0045] ): With the tip 61 of the bone cement fixing tool 60 fitted in the hole 2 of the bone cement 1 and its rotation suppressed, the screwdriver 20 is rotated to remove the internal fixation tool 10 while holding the bone cement fixing tool 60 with the handle 62 so as not to rotate. If the screw thread 15 on the distal side of the internal fixation tool 10 taps the pedicle 91 during insertion, a driving force in the removal direction can be applied to the internal fixation tool 10 by rotating it in the opposite direction to that during insertion, and the internal fixation tool 10 can be smoothly removed. For example, if the bone cement fixing tool 60 is rotated clockwise when advancing it toward the bottom of the hole 2, the internal fixation tool 10 is removed by rotating the screwdriver 20 counterclockwise while maintaining the clockwise force. Even if the bone cement 1 tries to rotate counterclockwise due to the force of rotating the screwdriver 20 counterclockwise, the rotation of the bone cement 1 can be suppressed by the force of rotating the bone cement fixing tool 60 clockwise. Fifth step (

[0046] ): The bone cement fixing device 60 is removed, and the incised skin 94 is sutured to complete the treatment. The tip 61 of the bone cement fixing device 60 can be removed by rotating it in the opposite direction to that of insertion. At this time, no force can be applied to suppress the rotation of the bone cement 1. However, since the insertion of the bone cement fixing device 60 involves tapping the bone cement 1 that has completely hardened after a long period of time since hardening, the bone cement 1 can be removed with a weak force without rotating it. Furthermore, by immediately loosening the bone cement fixing device 60 when the connection of the internal fixation device 10 to the bone cement 1 becomes slightly loose, it is possible to prevent the bone cement fixing device 60 from becoming too tightly stuck and becoming unable to be removed. In the unlikely event that the bone cement 1 easily rotates away from the surrounding body tissue, this can be solved by using two types of bone cement fixation instruments 60, one with a tip 61 having a relatively large outer diameter thread for forming a tapping groove, and the other with a tip 61 having a smaller outer diameter thread. A tapping groove is formed using the bone cement fixation instrument 60 with a large outer diameter thread, and then the bone cement fixation instrument 60 with a smaller outer diameter thread is inserted along the formed tapping groove to the bottom of the hole 2. The bone cement fixation instrument 60 with the smaller outer diameter thread is used to suppress the rotation of the bone cement 1 when the internal fixation device 10 is removed. This bone cement fixation instrument 60 has a smaller outer diameter thread and is simply inserted along the previously formed tapping groove, so it can be pulled out with a weak force by rotating it in the reverse direction. FIG. 19 is an explanatory diagram that illustrates another example of the procedure for removing the internal fixation device 10 during treatment using the treatment device of the third embodiment. Initial state (

[0051] ): As in

[0041] of Fig. 18, bone cement 1 is supported by an internal fixation device 10 inserted from a pedicle 91 and is thereby internally fixed to a patient's vertebral body 90. A hole 2 is formed in the bone cement 1 through a through-hole 16 of the internal fixation device 10. In Fig. 19, the hole 2 is assumed to be a cylindrical hole formed by a cylinder, but the same applies if a tapered cylinder type is used instead of a cylinder. First step (

[0052] ): The subcutaneous tissue from the skin 94, which is the body surface of the patient's back, to the vertebral body 90, which is the affected area, is incised and perforated, and instead of the guide pin 40 of

[0042] in Fig. 18, a bone cement fixation instrument 60 is inserted into the through hole 16 of the internal fixation instrument 10 inserted into the pedicle 91. With the handle 62 removed from the bone cement fixation instrument 60, the bone cement fixation instrument 60 is first inserted into the through hole 16 of the internal fixation instrument 10, or the driver 20 may be inserted in advance from the tip side of the bone cement fixation instrument 60 with the handle 62 attached, and the tip 61 of the bone cement fixation instrument 60 may be inserted into the through hole 16 of the internal fixation instrument 10 while holding it down with a hand. Second step (

[0053] ): Attach the handle 62 to the bone cement fixation tool 60 and screw the tip 61 into the hole 2. The through hole of the driver 20 is aligned with the inserted bone cement fixation tool 60, the driver 20 is guided to the internal fixation tool 10, and the tip of the driver 20 is fitted into the head (connection part) 13 of the internal fixation tool 10 to connect them. The tip 61 of the bone cement fixation tool 60 may be screwed into the hole 2 after the driver 20 and the internal fixation tool 10 are connected. Third step (

[0054] ): With the tip 61 of the bone cement fixing tool 60 fitted in the hole 2 of the bone cement 1 and its rotation suppressed, the screwdriver 20 is rotated to remove the internal fixation tool 10 while holding the bone cement fixing tool 60 with the handle 62 so as not to rotate. If the screw thread 15 on the distal side of the internal fixation tool 10 taps the pedicle 91 during insertion, the screwdriver 20 is rotated in the opposite direction to the insertion direction to apply a driving force in the removal direction to the internal fixation tool 10, and the internal fixation tool 10 can be smoothly removed. For example, if the bone cement fixing tool 60 is rotated clockwise when advancing it toward the bottom of the hole 2, the internal fixation tool 10 is removed by rotating the screwdriver 20 counterclockwise while maintaining the clockwise force. Even if the bone cement 1 tries to rotate counterclockwise due to the force of rotating the screwdriver 20 counterclockwise, the rotation of the bone cement 1 can be suppressed by the force of rotating the bone cement fixing tool 60 clockwise. Fourth step (

[0055] ): The bone cement fixing device 60 is removed, and the incised skin 94 is sutured to complete the treatment. As described above, the removal procedure can be simplified by using the bone cement fixing device 60 in place of the guide pin 40 in Fig. 18. In this case, it is more preferable to configure the bone cement fixing device 60 so that the handle 62 can be attached and detached. [Embodiment 4] FIG. 20 is an explanatory diagram that shows a schematic configuration example of a bone cement molding tool 50 and a driver 20 according to the treatment tools of the fourth and fifth embodiments of the present invention. The fourth embodiment is a modification of the third embodiment described with reference to Fig. 16, and not only the bone cement fixing instrument 60 but also the bone cement molding instrument 50 have threads that are tapped and screwed into the side wall of the hole 2. This allows a groove to be pre-tapped into the side wall of the hole 2. When it becomes necessary to remove the internal fixation instrument 10, the tapping threads of the bone cement fixing instrument 60 are screwed into the hole 2 along the above-mentioned groove pre-formed in the hole 2, so that the internal fixation instrument 10 can be screwed in and removed with a small force, and the bone cement fixing instrument can be easily removed after the internal fixation instrument is removed. FIG. 20 is illustrated in combination with the fifth embodiment described below, but it is not necessarily required to implement them in combination. [Embodiment 5] In the treatment instrument 100 of the fifth embodiment, the bone cement molding instrument 50 may be inserted into the through-hole of the driver 20 connected to the internal fixation instrument 10, and may be configured to protrude a predetermined length (for example, about 1 cm) from the tip of the internal fixation instrument 10, as illustrated in Fig. 20. This allows the bone cement molding instrument 50 to be inserted in a state in which the driver 20 and the internal fixation instrument 10 are connected to each other to form the hole 2, and as described later, the number of steps in the procedure can be reduced. In this case, it is more preferable that the bone cement molding tool 50 is configured so as to be detachable from the driver 20. This is because it is possible to selectively perform molding of the hole 2 and insertion of the internal fixation tool 10 into the bone cement 1 either simultaneously or separately. The bone cement molding tool 50 and the driver 20 may be configured, for example, so that they are connected and integrated by being provided with a screw structure at the distal end side of each of them and screwed in. Other connection methods may also be used. For example, they may be a connector structure that does not come off unless pulled strongly, or a latch structure that maintains the connection. This improves the operability of the treatment device 100 when molding the hole 2 and inserting the internal fixation device 10 into the bone cement 1 at the same time. This is because, as shown in the figure, the handle 27 of the driver 20 and the handle 52 of the bone cement molding tool 50 are integrated and can be configured to be easily held with one hand. FIG. 21 is an explanatory diagram showing the latter half of the procedure of embedding the internal fixation device 10 in the treatment using the treatment device 100 of the fifth embodiment. The first half of the procedure of embedding the internal fixation device 10 is the same as the first step ([1]) to the sixth step ([6]) described with reference to FIG. 10, and therefore the description will be omitted. Note that, like FIG. 10 and FIG. 11, FIG. 21 also shows a schematic cross-section of the affected part of the patient from the outside of the skin 94 through the pedicle 91 to the vertebral body 90, with the upper side of the page being the distal side and the lower side being the proximal side. The scale of the central axis direction (vertical direction of the page) is compressed, and the direction along the patient's body surface (horizontal direction of the page) is emphasized. The pedicle 91 is located on both the left and right sides of the vertebral body 90, so that the same treatment is performed on one vertebral body 90 from the left and right sides, but FIG. 21 shows one of them. Seventh step (

[0067] ): The balloon catheter 70 is pulled out from the driver 20 and the through hole of the internal fixation device 10, and the cement injector 80 is inserted to inject bone cement 1 into the vertebral body 90. Eighth step (

[0068] ): The cement injector 80 is pulled out from the through-hole of the driver 20 and the internal fixation device 10, and the bone cement molding device 50 is inserted through the through-hole of the driver 20, and its tip 51 is caused to protrude from the tip of the internal fixation device 10 into the bone cement 10. At this time, Fig. 21 is drawn assuming the bone cement molding device 50 illustrated in Fig. 20, but is not limited to this form of the bone cement molding device 50, and the tip 51 may be, for example, cylindrical or cylindrical tapered (frustum or cone), and may or may not have a thread for tapping on the outer circumferential surface. Ninth step (

[0069] ): The internal fixation device 10 is screwed into the filled bone cement 1 using the driver 20, and at the same time, the bone cement molding device 50 is also inserted into the bone cement 1 to mold the hole 2. As illustrated in Fig. 21, it is more preferable that the bone cement molding device 50 is integrated with the driver 20 by a screw structure at the distal end. However, this is not limited to this. Tenth step (

[0070] ): The driver 20 is withdrawn, and the incised skin 94 is sutured to complete the treatment. As described above, compared to the procedure described with reference to Figure 11, the procedure can be shortened by the amount that the insertion of the internal fixation device 10 and the molding of the hole 2 by the bone cement molding device 50 can be performed simultaneously. [Embodiment 6] In the first to fifth embodiments described above, a through hole through which a guide pin can pass may be provided in the bone cement fixing device 60. This allows the bone cement fixing device 60 to be guided to the hole 2 of the bone cement 1 in the affected area along the guide pin 40 that has been inserted in advance into the affected area. FIG. 22 is an explanatory diagram that diagrammatically shows an example of a procedure for removing the internal fixation device 10 during treatment using the treatment device of the sixth embodiment of the present invention. Initial state (

[0071] ): Bone cement 1 is internally fixed to a patient's vertebral body 90 by being supported by an internal fixation device 10 inserted from a pedicle 91. A hole 2 of a predetermined shape is formed in the bone cement 1 through a through hole 16 of the internal fixation device 10. First step (

[0072] ): The subcutaneous tissue from the skin 94, which is the surface of the patient's back, to the affected vertebral body 90 is incised and perforated, and a guide pin 40 is inserted into the through hole 16 of the internal fixation device 10 inserted into the pedicle 91, and its tip is brought to reach the hole 2 formed in the bone cement 1 inside the vertebral body 90. Second step (

[0073] ): By aligning the guide pin 40, the bone cement fixing tool 60 is guided together with the driver 20 toward the hole 2 formed in the bone cement 1. Third step (

[0074] ): Insert the bone cement fixing device 60 into the hole 2, connect the driver 20 to the internal fixation device 10 at the head 13, and remove the guide pin 40. Fourth step (

[0075] ): With the tip 61 of the bone cement fixing device 60 fitted in the hole 2 of the bone cement 1 and the movement in the direction of rotation and / or removal being suppressed, the handle 62 is used to hold the bone cement fixing device 60 so that it does not rotate and is not pulled out, and the driver 20 is rotated to remove the internal fixation device 10. As in the other embodiments described above, if the screw thread 15 provided on the distal side of the internal fixation device 10 taps the pedicle 91 during insertion, the internal fixation device 10 can be given a driving force in the direction of removal by rotating it in the opposite direction to that during insertion, and the internal fixation device 10 can be smoothly removed. Alternatively, if the internal fixation device 10 has a structure without a screw thread, the internal fixation device 10 can be knocked up and removed using an instrument such as the driver 20 or forceps for holding the internal fixation device 10, while the movement in the direction of removal of the bone cement 1 is suppressed by the bone cement fixing device 60. Fifth step (

[0076] ): The bone cement fixing device 60 is removed, and the incised skin 94 is sutured to complete the treatment. As described above, by providing the bone cement fixing device 60 with a through hole through which a guide pin can pass, the bone cement fixing device 60 can be easily and accurately guided into the hole 2 formed by the bone cement molding device 50, so that the procedure of removing the internal fixation device 10 can be carried out smoothly. The invention made by the inventor has been specifically described above based on an embodiment, but it goes without saying that the invention is not limited thereto and can be modified in various ways without departing from the spirit of the invention. The present invention relates to a cylindrical internal fixation device for medical use, and is particularly suitable for use in surgery for internal fixation of an affected vertebral body. 1. Bone cement 2 holes 10 internal fixation device 12 Shaft 13 Head (connection part with driver) 14 Groove 15 Thread 16 Through hole 17 Slope section 20 Driver 25 Connection with inner cylinder 26 Male thread 27 Driver's handle 30 Inner cylinder 31 tongue of inner cylinder 32 Tip of inner cylinder 33 Notch 34 Thread at tip of inner cylinder 35 Driver connection 36 Female thread 37 Inner barrel handle 40 Guide pin 50 Bone cement molding equipment 51 Tip of bone cement molding instrument 52 Handle 53 Connecting part 54 Thread 60 Bone cement fixation device 61 Tip of bone cement fixation device 62 Handle 64 Through hole 70 Balloon catheter 71 Balloon 80 Cement injector 90 vertebral body 91 vertebral pedicle 92 vertebral arch 93 Spinal canal 94 Skin 100 Treatment equipment

Claims

1. A treatment device including a bone cement molding device and a bone cement fixation device, which are inserted into an internal fixation device for supporting the bone cement from the pedicle by being integrated with the bone cement filled in the vertebral body, The internal fixation device has a through-hole extending from the head to the tip in a central axis direction, the bone cement molding tool is inserted into the bone cement through the through-hole of the internal fixation tool to mold a hole of a predetermined shape; the bone cement fixing device has a tip portion to be inserted into the hole, and is inserted into the bone cement in which the hole is formed through the through-hole of the internal fixation device, and by inserting the tip portion into the hole, the rotation of the bone cement around the central axis and / or the movement in the pulling-out direction caused by the operation of removing the internal fixation device from the bone cement is suppressed. treatment equipment.

2. In claim 1, The bone cement fixation tool has a screw thread that taps and screws into the side wall of the hole. treatment equipment.

3. In claim 1, the treatment instrument further comprises a driver; The internal fixation device is connectable to a driver at the head, the driver has a through-hole that communicates with the through-hole of the internal fixation instrument when connected to the internal fixation instrument and allows the distal end portions of the bone cement molding instrument and the bone cement fixation instrument to pass through. treatment equipment.

4. In claim 3, The bone cement molding tool is inserted into the through-hole of the driver connected to the internal fixation tool and protrudes from the tip of the internal fixation tool by a predetermined length. treatment equipment.

5. In claim 4, The bone cement molding tool is detachably connected to the driver. treatment equipment.

6. In claim 5, the driver has a threaded structure at a distal end thereof that can be connected to the bone cement molding tool; treatment equipment.

7. 2. The bone cement fixing device according to claim 1, wherein the handle portion and the shaft portion are detachable. treatment equipment.

8. In any one of claims 1 to 7, The distal end of the bone cement molding instrument has a circular cross section whose diameter is constant or decreases toward the distal end, The bone cement fixation tool has a screw thread that taps and screws into the side wall of the hole. treatment equipment.

9. In claim 1, The treatment instrument further includes a guide pin, and the bone cement fixing instrument has a through hole through which the guide pin can pass. treatment equipment.

10. In claim 1, The tip of the bone cement molding instrument is prismatic or tapered, the cross section of which decreases toward the tip, the bone cement fixing tool has a tip shape that can abut against a side wall of the hole to suppress rotation of the bone cement; treatment equipment.

11. 11. The bone cement fixing device according to claim 10, wherein the handle portion and the shaft portion are detachable. treatment equipment.

12. In claim 10, the treatment instrument further comprises a driver; The internal fixation device is connectable to a driver at the head, the driver has a through-hole that communicates with the through-hole of the internal fixation instrument when connected to the internal fixation instrument and allows the tip portions of the bone cement molding instrument and the bone cement fixation instrument to pass through. treatment equipment.

13. In any one of claims 10 to 12, The treatment instrument further includes a guide pin, and the bone cement fixing instrument has a through hole through which the guide pin can pass. treatment equipment.