WO2012066905A1

WO2012066905A1 - Drug injection device

Info

Publication number: WO2012066905A1
Application number: PCT/JP2011/074480
Authority: WO
Inventors: 早川浩一
Original assignee: テルモ株式会社
Priority date: 2010-11-19
Filing date: 2011-10-25
Publication date: 2012-05-24
Also published as: JP2014030436A

Abstract

A drug injection device (10A) which comprises: a hollow tubular member (12) having a drug discharge port at the front end; a first plunger (14) liquid-tightly inserted into the hollow part of the tubular member (12), said first plunger (14) having a through hole (30) which passes through in the axial direction; a feeding screw structure (44) which displaces the first plunger (14) along the axial direction relative to the tubular member (12), as the first plunger (14) rotates against the tubular member (12); and a second plunger (16), in a liquid-tight and slidable manner, inserted in the axial direction into the through hole (30).

Description

Drug infusion tool

The present invention relates to a drug injection device used for discharging a drug when the drug is injected into an injection space.

In recent years, percutaneous vertebroplasty (PVP) is performed for vertebral body compression fractures caused by osteoporosis or cancer by injecting a filling material that hardens with time through a bone biopsy needle inserted into the fractured vertebral body. As the filler, for example, calcium phosphate bone cement or polymethylmethacrylate bone cement (hereinafter, also simply referred to as “bone cement”) having X-ray contrast properties is used. Normally, bone cement has a very high viscosity, and the pressure loss due to the sponge is very large in the vertebra filled with the bone cement, so it is necessary to inject a small amount at a high pressure of 3 MPa or more at the time of injection. .

Therefore, as such an injection tool, a configuration is used in which bone cement is discharged while applying a high pressure by a general piston type or feed screw type syringe. A feed screw type injection tool is disclosed in, for example, Japanese Patent No. 4257976.

As described above, for example, a drug injection tool used for injecting a liquid drug (bone cement) having a high viscosity into a space with high pressure loss such as in bone can discharge the drug in an appropriate amount at a high pressure. It is desirable to be configured.

However, the normal piston-type injection tool used for bone cement injection is configured as a syringe with a small diameter of 1 to 3 mL so that high pressure can be generated manually and injection can be performed precisely while controlling small amounts. Using a plurality of these, finally, 5 to 20 mL of bone cement is injected into the bone. For this reason, it is necessary to prepare a plurality of syringes filled with bone cement per one bone in the piston-type injection tool, which is complicated.

Further, in order to suppress the X-ray exposure of the surgeon, an extension tube is provided between the biopsy needle and the syringe, and an injection tool configured to inject bone cement discharged from the syringe into the bone through the extension tube Has been proposed. However, since high viscosity bone cement flows through the elongated extension tube, the pressure loss is large, and a syringe-type injection tool requires a large operating force for the pressing operation and is difficult to inject.

On the other hand, with a feed screw type injection device, even when injection is performed using an extension tube, a relatively large amount of injection can be performed at a high pressure by a rotating operation with a relatively small operating force. However, with a lead screw type injection device, the high pressure state in the cylinder is maintained without being released during injection, so it is difficult to stop immediately when it is desired to stop the injection operation. Not suitable.

The present invention has been made in consideration of such problems, and can inject a drug quickly and accurately with a relatively small operating force when injecting a drug into a target injection space. The purpose is to provide.

In order to achieve the above object, the present invention provides a drug injection device for discharging a drug filled inside, a hollow cylinder having a drug discharge port at the tip, and a liquid in a hollow part of the cylinder. A first pusher having a through hole that is closely inserted and penetrates in the axial direction, and the first pusher is displaced in the axial direction with respect to the cylindrical body as the first pusher rotates with respect to the cylindrical body. And a second pusher inserted in the through hole so as to be slidable in a liquid-tight manner in the axial direction.

According to the medicine injection device configured as described above, as a first operation method, a relatively large amount can be obtained with a small operation force by rotating and injecting the first pusher up to a roughly target injection amount. When the amount of the medicine is discharged and the injection amount becomes close to the target injection amount, the second pusher can be pressed to perform precise injection. Therefore, quick and precise injection can be performed. Further, as a second operation method, the second pusher is pressed to perform precise injection, and the first pusher is rotated to return the second pusher to its original position. By alternately performing a plurality of times, precise injection is possible in all injections.

The drug injection tool further includes a guide member that is engageable with a base end portion of the cylindrical body and has a female screw portion penetratingly formed, and an outer peripheral portion of the first pusher is provided with the female screw portion. The external thread part to be screwed may be formed along the axial direction, and the feed screw structure may be constituted by the internal thread part and the external thread part.

This eliminates the need to provide the cylindrical body with a female screw portion that is screwed into the male screw portion of the first pusher, so that the feed screw structure can be easily configured.

In the above-described drug injecting device, it is preferable that a first seal member slidable in a liquid-tight manner along the inner peripheral surface of the cylindrical body is provided on the distal end portion or the outer periphery of the distal end portion of the first pusher.

Thereby, the liquid tightness between the first pusher and the cylinder can be suitably secured. Moreover, since the chemical | medical agent with which the cylinder body was filled does not contact an internal thread part and an external thread part, the operation force at the time of rotating operation of a 1st pusher may be small.

In the medicine injection tool, a first positioning means for restricting a position where the second pusher is displaced to the most distal side with respect to the first pusher, and the second pusher with respect to the first pusher. It is preferable to further include a second positioning means for restricting the position displaced most proximally.

According to the above configuration, since the movable range of the second pusher is restricted to a certain range, a certain amount of injection is performed by pressing the second pusher from the most proximal end side to the most distal side of the movable range. It can be performed. Further, the second pusher is not excessively advanced, and the second pusher is prevented from coming out from the first pusher to the proximal end side, so that it is easy to handle.

In the above-described drug injecting device, it is preferable that a second seal member slidable in a liquid-tight manner along the inner peripheral surface of the through hole is provided on the distal end portion or the outer periphery of the distal end portion of the second pusher.

Thereby, the liquid tightness between the inner peripheral surface of the through hole and the second pusher can be suitably secured.

In the above-described drug injector, the tip of the second pusher may be located in the through hole of the first pusher regardless of the position of the second pusher within the movable range.

As a result, when the second pusher is moved to the proximal end side with respect to the first pusher, a medicine filling chamber is formed in the through hole of the first pusher, so that the second pusher is pressed. By operating, the medicine in the through hole can be pushed out and the medicine can be reliably discharged from the medicine injection tool.

In the above-mentioned medicine injection tool, a handle that is expanded outward is provided on the outer periphery of the proximal end portion of the first pusher, and a flange portion that is expanded outward is provided on the outer periphery of the proximal end portion of the second pusher. Should be provided.

Accordingly, for example, when the second pusher is moved toward the distal end side with respect to the first pusher by putting a finger other than the thumb on the handle and pushing the flange portion with the thumb, the push against the second pusher Operation can be performed easily.

In the above-described drug injecting device, the drug may be bone cement to be injected into the bone.

This makes it possible to inject bone cement quickly and accurately.

In the above-described drug injector, the second pusher may be provided with an air discharge passage for discharging the air in the cylindrical body.

Thus, the cylinder and the outside can be communicated with each other via the air discharge passage, so that the air in the cylinder can be discharged to the outside without directing the cylinder upward.

In the medicine injection tool, the first pusher includes a rod inserted through the cylindrical body and the handle provided at a proximal end of the rod, and the handle protrudes from a proximal end of the rod. The second pusher may extend in the proximal direction so as to at least partially cover the second pusher.

When the handle is configured as described above, when the first pusher is moved in the distal direction relative to the cylindrical body by rotating the first pusher, the user's finger is moved to the second pusher. Contact is prevented and operability is improved.

In this case, the handle may be provided with a notch that extends along the axial direction of the second pusher and opens in the proximal direction of the handle.

The user can perform a pressing operation on the second pusher through the notch, and the handle does not get in the way of the pressing operation, and the pressing operation can be performed smoothly.

In the above-described drug injection device, the handle may be provided with a recess that opens in a proximal direction and into which the flange portion of the second pusher can be immersed.

According to this configuration, the first pusher and the second pusher are integrated by grasping the handle so that the proximal end side of the handle of the first pusher is covered with a palm and rotating the first pusher. Can be moved toward the tip. When stopping the injection of the medicine, the pressure in the system is reliably released by moving the second pusher in the proximal direction relative to the first pusher by releasing the handle. Therefore, injection can be stopped reliably and precise injection can be performed.

In the above-mentioned medicine injection tool, an outwardly enlarged handle is provided on the outer periphery of the base end portion of the second pusher so that the first pusher and the second pusher cannot rotate relative to each other. It may be fitted.

According to this configuration, the first pusher and the second pusher can be integrally moved in the distal direction by rotating the handle of the second pusher. When stopping the injection of the medicine, the pressure in the system is reliably released by moving the second pusher in the proximal direction relative to the first pusher by releasing the handle. Therefore, injection can be stopped reliably and precise injection can be performed.

According to the drug injection device according to the present invention, when a drug is injected into a target injection space, it can be quickly and accurately injected with a relatively small operation force.

It is a perspective view showing a medicine injection tool concerning a 1st embodiment of the present invention. It is a longitudinal cross-sectional view of the chemical injection tool shown in FIG. FIG. 3A is a diagram for explaining a first operation method of the drug injection device shown in FIG. 1, and FIG. 3A shows a state in which the drug injection device filled with bone cement is connected to a bone cement injection needle through an extension tube; FIG. 3B is a diagram illustrating a state in which the first pusher is displaced to the tip side with respect to the state of FIG. 3A. It is a figure explaining the 1st operation method of the medicine injection tool shown in Drawing 1, and is a figure showing the state where the 2nd pusher was pushed in to the tip side to Drawing 3B. It is a figure explaining the 2nd operation method of the medicine injection tool shown in Drawing 1, and Drawing 5A shows the state where the medicine injection tool filled with bone cement was connected to the bone cement injection needle via the extension tube and the stopcock FIG. 5B is a diagram illustrating a state in which the second pusher is displaced to the most distal side with respect to the state of FIG. 5A. FIG. 6A is a diagram for explaining a second operation method of the pharmaceutical injection device shown in FIG. 1, and FIG. 6A is a diagram showing a state in which the first pusher is slightly displaced toward the distal end side with respect to FIG. 5B. 6B is a view showing a state in which the second pusher is displaced to the most distal side with respect to FIG. 6A. FIG. 7A is a partially omitted vertical cross-sectional view of a medicine injection device provided with a second pusher according to a modification, and FIG. 7A is a view showing a state in which the air discharge passage is closed, and FIG. It is a figure which shows the state open | released. It is sectional drawing which shows the chemical | medical agent injection tool which concerns on 2nd Embodiment of this invention. FIG. 9A is a diagram for explaining a first operation method of the drug injection tool shown in FIG. 8, and FIG. 9A shows a state in which the drug injection tool filled with bone cement is connected to a bone cement injection needle through an extension tube. FIG. 9B is a diagram illustrating a state in which the first pusher is displaced to the tip side with respect to the state of FIG. 9A. It is a figure explaining the 1st operation method of the medicine injection tool shown in Drawing 8, and is a figure showing the state where the 2nd pusher was pushed in to the tip side to Drawing 9B. It is a figure explaining the 2nd operation method of the medicine injection tool shown in Drawing 8, and Drawing 11A shows the state where the medicine injection tool filled with bone cement was connected to the bone cement injection needle via the extension tube and the stopcock FIG. 11B is a diagram showing a state in which the second pusher is displaced toward the tip side with respect to the state of FIG. 11A. FIG. 12A is a diagram for explaining a second operation method of the drug injection device shown in FIG. 8, and FIG. 12A is a diagram showing a state in which the first pusher is slightly displaced toward the distal end side with respect to FIG. 11B. FIG. 12B is a diagram showing a state in which the second pusher is pushed toward the tip side with respect to FIG. 12A. It is a perspective view which shows the chemical | medical agent injection tool which concerns on 3rd Embodiment of this invention. It is a longitudinal cross-sectional view of the chemical injection tool shown in FIG. FIG. 15 is a partially omitted enlarged cross-sectional view showing a distal end portion of a first pusher of the pharmaceutical injection device shown in FIG. 14. It is sectional drawing which shows the chemical injection tool which concerns on 4th Embodiment of this invention. FIG. 17A is a diagram for explaining an operation method of the pharmaceutical injection tool shown in FIG. 16, and FIG. 17A is in the middle of injecting bone cement into the bone by moving the first pusher and the second pusher in the distal direction. FIG. 17B is a diagram showing a state in which the injection of bone cement is stopped. It is sectional drawing which shows the chemical injection tool which concerns on 5th Embodiment of this invention. 19A is a cross-sectional view taken along line XIXA-XIXA in FIG. 18, and FIG. 19B is a cross-sectional view taken along line XIXB-XIXB in FIG. FIG. 20A is a diagram for explaining an operation method of the medicine injection tool shown in FIG. 18, in which FIG. 20A is in the process of injecting bone cement into the bone by moving the first pusher and the second pusher in the distal direction. FIG. 20B is a diagram showing a state in which the injection of bone cement is stopped. It is a longitudinal cross-sectional view of the chemical injection tool provided with the cylindrical cover. FIG. 22A is a diagram of a first state for explaining a method of filling bone cement from the tip of a cylindrical body, and FIG. 22B is a diagram of a second state for explaining the method.

Hereinafter, preferred embodiments of the drug injection device according to the present invention will be described with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is a perspective view showing a pharmaceutical injection device 10A according to the first embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the pharmaceutical injection device 10A shown in FIG. The drug injection tool 10A is an instrument used for discharging a drug when a drug (filler, injection material) is injected into a desired injection space. For example, bone cement is used in percutaneous vertebroplasty. Used for injection into bone. Examples of the drug include bone cements such as calcium phosphate bone cement (CPC) and polymethyl methacrylate (PMMA) bone cement, and calcium phosphate ceramics, alumina ceramics, zirconia ceramics, and titanium. Granules made of inorganic materials can also be used.

As shown in FIGS. 1 and 2, the drug injection device 10 </ b> A includes a cylindrical body 12, a first pusher 14, and a second pusher 16. The cylindrical body 12 includes a body portion 18 having a lumen (hollow portion) extending in the axial direction, a distal end tube portion 20 protruding from the distal end portion of the body portion 18 toward the distal end side, and a proximal end portion of the body portion 18. And flange portions 22 projecting outward (radially outward) on both sides. The body part 18, the distal end pipe part 20, and the flange part 22 are integrally formed.

The body portion 18 is formed in a hollow cylindrical shape having an inner diameter and an outer diameter that are substantially constant along the axial direction, and a scale 24 indicating the amount of the drug is displayed on the outer peripheral surface thereof. The internal volume of the body portion 18 is set to about 5 to 20 mL.

The tip tube portion 20 forms a medicine discharge port and is configured as a luer connector. On the outer side of the distal end tube portion 20, a lock portion 28 that protrudes in the axial direction from the distal end portion of the body portion 18 concentrically with the distal end tube portion 20 and has an internal thread portion 26 formed on the inner peripheral surface is provided. When the medicine is injected by such a tip tube portion 20 and the lock portion 28, it can be connected to an extension tube 92 (see FIG. 3A or the like) or a bone cement injection needle 84 described later.

In the cylindrical body 12 configured as described above, a filling chamber 19 for filling a medicine is formed by a space surrounded by the cylindrical body 12, the first pusher 14 and the second pusher 16. .

Although the constituent material of the cylinder 12 is not particularly limited, for example, polyolefin such as polypropylene, polyethylene, cyclic polyolefin, polymethylpentene 1, polyester, nylon, polycarbonate, polymethyl methacrylate (PMMA), polyetherimide (PEI), It may be formed of a resinous material such as polyethersulfone, polyetheretherketone (PEEK), fluororesin, polyphenylene sulfide (PPS), or polyacetal resin (POM), a metallic material such as stainless steel, glass, or the like. Moreover, it is preferable that the constituent material of the cylindrical body 12 is substantially transparent in order to ensure internal visibility. Moreover, it is preferable that it has strength, elasticity and chemical resistance that can withstand high pressure.

The first pusher 14 is inserted into the hollow portion of the cylindrical body 12, and has a through hole 30 penetrating linearly in the axial direction. The through-hole 30 includes a large-diameter portion 30a constituting the distal end side of the through-hole 30 and a small-diameter portion 30b constituting the proximal end side of the through-hole 30. In the illustrated example, the large-diameter portion 30a and the small-diameter portion 30b. The step portion 32 that is a boundary portion between the first pusher 14 and the intermediate portion in the axial direction of the first pusher 14 is set at a position slightly on the base end side.

A first seal member 36 is attached to the head 34 which is the tip of the first pusher 14. In the illustrated configuration example, a plurality (two in the illustrated example) of annular seal grooves 37 extending in the circumferential direction are formed at intervals on the outer periphery of the head portion 34, and a ring-shaped first seal is formed in each seal groove 37. A member 36 (for example, a silicone O-ring or the like) is disposed. By sliding the first seal member 36 in the axial direction while being in close contact with the inner peripheral surface of the cylindrical body 12, the liquid-tightness can be reliably maintained and the slidability can be improved. Instead of the ring-shaped first seal member 36, a gasket made of an elastic resin material may be attached to the tip of the first pusher 14.

The outer diameter of the distal end portion of the first pusher 14 (in the illustrated example, the outer diameter of the head portion 34 provided with the first seal member 36) is the same as or slightly smaller than the inner diameter of the body portion 18 of the cylindrical body 12, For example, it is set to about 5 to 50 mm, and more preferably set to about 10 to 20 mm. If the outer diameter of the distal end portion of the first pusher 14 is too large, the operation force for rotating the first pusher 14 of the drug injection device 10A filled with a high-viscosity drug becomes too large, and the operation becomes difficult. It becomes difficult. Moreover, if the outer diameter of the front end portion of the first pusher 14 is too small, the excluded volume (discharge amount) per one rotation with respect to the cylindrical body 12 decreases, and rapid injection becomes difficult.

In the first pusher 14, a male screw portion 38 is formed along the axial direction in a certain range on the base end side of the head 34. The outer diameter of the male screw portion 38 is smaller than the inner diameter of the body portion 18 of the cylindrical body 12. The first pusher 14 is inserted through the guide member 40. A female screw portion 42 is formed through the guide member 40, and the first pusher 14 is supported by the guide member 40 when the female screw portion 42 and the male screw portion 38 are screwed together. In other words, the feed screw structure 44 that displaces the first pusher 14 in the axial direction with respect to the cylindrical body 12 by the rotation of the first pusher 14 with respect to the cylindrical body 12 by the female screw portion 42 and the male screw portion 38. It is configured.

In the guide member 40, a pair of engaging portions 46 that can be engaged with the flange portion 22 of the cylindrical body 12 are provided on both outer sides in the radial direction of the female screw portion 42, and between the pair of engaging portions 46. A recess 48 that opens forward is provided. In the following description, with respect to the guide member 40, the direction in which the pair of engaging portions 46 face each other is referred to as the “longitudinal direction”, and is the direction perpendicular to the central axis of the female screw portion 42. A direction perpendicular to the direction is called a “short direction”.

The engaging portion 46 has an engaging groove 50 into which the flange portion 22 can be inserted. Each engagement groove 50 in the illustrated example is a notch that is recessed outward from the side wall surface of the recess 48, and is formed symmetrically with respect to the central axis of the female screw portion 42. It extends in the hand direction. In addition, each engagement groove 50 has one end in the extending direction opened on the side surface of the guide member 40 and the other end in the extending direction is closed.

A cylindrical portion 52 protruding in the proximal direction is provided at the proximal end portion of the guide member 40. The inner diameter of the cylindrical portion 52 is larger than the outer diameters of the male screw portion 38 and the intermediate portion 43 in the first pusher 14. The first pusher 14 can move to the distal end side with respect to the guide member 40 to a position where the proximal end surface of the cylindrical portion 52 and the distal end surface of the handle 54 come into contact with each other. In other words, the base end surface of the cylindrical portion 52 and the distal end surface of the handle 54 constitute a means for restricting the position where the first pusher 14 is displaced to the most distal side with respect to the guide member 40. In addition, you may make it regulate the position only by the end point of the external thread part 38 provided in the 1st pusher 14, without providing the cylinder part 52. FIG.

In the state where the guide member 40 configured as described above and the axis of the cylindrical body 12 coincide with each other, and the longitudinal direction of the guide member 40 and the longitudinal direction of the flange portion 22 of the cylindrical body 12 are orthogonal to each other. When the flange portion 22 is inserted into the recessed portion 48 of the 40 and then the guide member 40 and the cylindrical body 12 are relatively rotated, the flange portion 22 and the engaging portion 46 are engaged. Thereby, as shown in FIG. 2, the guide member 40 and the cylinder body 12 are connected in a state where the first pusher 14 is inserted into the hollow portion of the cylinder body 12.

At the base end portion of the first pusher 14, a handle 54 (rotation operation portion) whose diameter is increased outward (radially outward) is provided. The handle 54 is a portion that a user grips (pinch) with fingers when the first pusher 14 is rotated with respect to the cylindrical body 12 about the axis, and is formed in a substantially disc shape in the illustrated example. Has been. A plurality of grooves 56 are formed on the outer periphery of the handle 54 at intervals in the circumferential direction so that the user does not slip when gripping and rotating. The shape of the handle 54 is not limited to a disk shape, and may be a wing shape that protrudes outward in the radial direction from the base end portion of the first pusher 14.

The constituent material of the first pusher 14 can be selected from those exemplified as the constituent material of the cylindrical body 12 described above. In addition, the constituent material of the first seal member 36 is not particularly limited. For example, olefin elastomer, styrene elastomer, polyester elastomer, polyurethane elastomer, silicone rubber, butyl rubber, vulcanized rubber such as fluorinated rubber, and further to them. It may be formed of a fluororesin-coated one.

The second pusher 16 is inserted through the through hole 30 of the first pusher 14 so as to be freely displaceable in the axial direction within a restricted range. The second pusher 16 includes a rod 58 slidably inserted into the through hole 30 of the first pusher 14, a second seal member 60 provided (attached) at the tip of the rod 58, and a rod And a flange portion 62 provided (attached) to the proximal end portion of 58.

The rod 58 has a smaller diameter than the first pusher 14. Of the rod 58, the second pusher 16 is displaced most proximally with respect to the first pusher 14, and the second pusher is formed on the outer peripheral surface of the portion protruding from the first pusher 14 toward the proximal end. A scale 64 indicating the position (pushing amount, insertion amount) in the axial direction with respect to the child 16 is provided at regular intervals. The scale 64 is not particularly limited as long as it can be visually recognized by the user. For example, the scale 64 may be constituted by a groove extending in the circumferential direction, or may be made of ink (paint) having a color different from that of the rod 58. It may be displayed.

A diameter-expanded portion 66 having an outer diameter slightly larger than other portions is formed on the tip side of the rod 58. A stepped portion 68 is formed by the outer diameter difference between the enlarged diameter portion 66 and a portion on the proximal end side of the enlarged diameter portion 66 (hereinafter referred to as a narrow diameter portion 67). The second pusher 16 is moved to the position where the end face (stepped portion 68) on the proximal end side of the enlarged diameter portion 66 and the stepped portion 32 provided on the inner peripheral portion of the first pusher 14 come into contact with each other. It can move to the base end side with respect to the child 14. In other words, in the present embodiment, the stepped portion 32 and the stepped portion 68 constitute the second positioning means 70 that regulates the position where the second pusher 16 is displaced to the most proximal side with respect to the first pusher 14. Yes.

The second seal member 60 in the illustrated example has a bottomed cylindrical shape, and is attached to a mushroom-type (flange-type) engagement protrusion 72 formed at the tip of the second pusher 16. The second seal member 60 may be formed in a ring shape that is attached to the outer periphery of the distal end portion of the second pusher 16. The constituent material of the second seal member 60 can be selected from those exemplified as the constituent material of the first seal member 36 described above. The stroke (displacement length) of the second pusher 16 relative to the first pusher 14 is set to about 25 to 100 mm.

When the second pusher 16 is displaced to the most proximal side with respect to the first pusher 14, the inner volume of the through-hole 30 on the distal end side relative to the second pusher 16 (that is, the medicine injection tool 10A has a medicine). The amount of medicine discharged by the second pusher when the second pusher 16 is moved from the most proximal side to the most distal side with respect to the first pusher 14 in a state filled with is 1 to 3 mL. Set to degree.

The outer diameter of the tip of the second pusher 16 (in the illustrated example, the outer diameter of the second seal member 60) is, for example, set to about 2 to 7 mm, and more preferably set to about 3 to 6 mm. . If the outer diameter of the distal end portion of the second pusher 16 is too large, the operation force when the second pusher 16 of the medicine injection device 10A filled with a high-viscosity medicine is pressed becomes too large, and the operation becomes difficult. It becomes difficult. If the outer diameter of the tip of the second pusher 16 is too small, the excluded volume (discharge amount) per unit movement amount in the axial direction is too small.

The flange portion 62 is a portion that the user presses with a finger (for example, thumb) when pressing the second pusher 16 toward the distal end side, and has an appropriate size so that it can be easily pressed. Thereby, for example, when the second pusher 16 is moved to the distal end side with respect to the first pusher 14 by putting the index finger and the middle finger on the handle 54 and pressing the flange portion 62 with the thumb, the second pusher The pressing operation on the child 16 can be easily performed.

The flange portion 62 is fitted and connected to the proximal end portion of the rod 58. The connection structure by fitting the rod 58 and the flange portion 62 may be either screw fitting or uneven fitting (taper fitting). The connecting structure between the rod 58 and the flange portion 62 is not limited to the fitting structure, and may be a structure fixed by bonding, heat sealing, or the like. Further, the rod 58 and the flange portion 62 may be integrated, and in this case, the tip portion of the second pusher 16 is composed of two parts.

The second pusher 16 can move with respect to the first pusher 14 to a position where the distal end surface 62a of the flange portion 62 and the proximal end surface 54a of the handle 54 come into contact with each other. That is, in the present embodiment, the position where the second pusher 16 is displaced to the most distal side with respect to the first pusher 14 is regulated by the distal end surface 62a of the flange portion 62 and the proximal end surface 54a of the handle 54. One positioning means 74 is configured. In the illustrated configuration example, when the second pusher 16 is moved to the most distal side with respect to the first pusher 14, the most distal portion of the second pusher 16 (the tip surface of the second seal member 60) is It almost coincides with the most advanced portion of the one pusher 14.

In the medicine injection tool 10A, the distal end portion of the second pusher 16 (in the illustrated example, the second seal member 60) is positioned at the first pusher 14 regardless of the position of the second pusher 16 within the movable range. It is located in the through hole 30. Thereby, in the state where the second pusher 16 is moved to the proximal end side with respect to the first pusher 14, the medicine filling chamber 19 is formed in the through hole 30 of the first pusher 14. By pressing the two pushers 16, the medicine in the through hole 30 can be pushed out and the medicine can be reliably discharged from the medicine injection tool 10A.

The constituent material of the rod 58 and the flange portion 62 can be selected from those exemplified as the constituent material of the cylindrical body 12 described above.

The drug injection device 10A according to the first embodiment of the present invention is basically configured as described above, and hereinafter, the drug injection device 10A is percutaneously subjected to percutaneous vertebroplasty for its action and effect. The case of using in FIG.

First, a first usage method (operation method) of the pharmaceutical injection device 10A will be described. As shown in FIG. 3A, a predetermined amount (for example, 5 to 20 mL) of bone cement 80 is filled in the filling chamber 19 in advance. In this filling, for example, the bone cement 80 prepared in advance is filled from the rear end (or the front end) of the cylindrical body 12, and then the first pusher 14 to which the second pusher 16 and the guide member 40 are mounted in advance. Is attached to the cylinder 12. At this time, the second pusher 16 has a tip positioned at the tip of the first pusher 14 and the guide member 40 is positioned at the tip of the first pusher 14. And the air in the cylinder 12 is discharged outside by rotating the 1st pusher 14 and advancing the front-end | tip of the cylinder 12 upwards. 3A shows a state in which the second pusher 16 is moved to the proximal end side with respect to the first pusher 14, and the bone cement 80 is also filled in the through hole 30. FIG.

Next, the cylindrical body 12 of the pharmaceutical injection device 10A and the injection port 86 of the bone cement injection needle 84 punctured into the bone 82 to be injected with the bone cement 80 are connected via the extension tube 92. By using the extension tube 92, it is possible to operate the drug injection tool 10A in a state where the hand of the operator (user) is retracted outside the X irradiation region.

Here, the bone cement injection needle 84 includes, for example, a hollow puncture needle 85 made of a metal material and a hub 87 made of, for example, a resin material fixed to the proximal end portion of the puncture needle 85. Have. An injection port 86 communicating with the lumen (hollow portion) of the puncture needle 85 is provided on the upper portion of the hub 87. One end of the extension tube 92 is provided with a connector 88 that is detachably connected to the injection port 86, and the other end of the extension tube 92 is provided with a connector 90 that is detachable from the distal end tube portion 20 of the cylindrical body 12. Yes.

The extension tube 92 preferably has a configuration in which a thread of Kevlar (registered trademark), nylon, polyphenylene sulfide, stainless steel or the like is wound around the flexible tube wall or the outer surface in a net or coil shape from the viewpoint of pressure resistance. However, it may be a multilayer tube in which water-resistant polypropylene or fluororesin is disposed only on the inner surface. The length of the extension tube 92 is preferably set to about 200 to 500 mm so that the operator's (user's) hand can be securely retracted outside the X irradiation region. Further, the distal end portion of the extension tube 92 may be angled.

In FIG. 3A, the connector 88 provided at one end of the extension tube 92 is connected to the injection port 86 of the hub 87, and the connector 90 provided at the other end of the extension tube 92 is connected to the distal end tube portion 20 of the cylindrical body 12. It is connected to.

In this state, the bone cement 80 filled in the drug injection tool 10A is discharged under X-ray fluoroscopy and injected into the bone 82. At the time of this injection operation, in the first usage method, first, the first pusher 14 is rotated and moved to the distal end side with respect to the cylindrical body 12. Then, as the first pusher 14 moves toward the distal end side with respect to the cylindrical body 12, the filling chamber 19 is pressurized to a high pressure, and the bone cement 80 moves the distal end pipe portion 20, the extension tube 92, and the bone cement injection needle 84. And injected into the bone 82. Since the movement of the first pusher 14 toward the distal end can be performed by a rotating operation, the bone cement 80 can be injected with a relatively small operation force, and the first pusher 14 has a relatively large diameter. A relatively large amount of bone cement 80 can be rapidly injected. Further, the injection amount of the bone cement 80 per rotation of the first pusher 14 may be set to a predetermined amount (for example, 0.25 to 2 mL).

It should be noted that the second pusher 16 may be displaced to the tip side with respect to the first pusher 14 before the first pusher 14 is rotated. In such a case, since the second pusher 16 receives pressure from the bone cement 80 as the first pusher 14 is rotated, the second pusher 16 is eventually moved relative to the first pusher 14. Move to the proximal side.

After the bone cement 80 has been injected to the approximate target injection amount by the rotation operation with respect to the first pusher 14, next, as shown in FIG. On the other hand, it moves to the tip side. Then, as the second pusher 16 moves toward the distal end side with respect to the first pusher 14, the filling chamber 19 is pressurized to a high pressure, and the bone cement 80 is moved to the distal end tube portion 20, the extension tube 92, and the bone cement injection needle. 84 and injected into the bone 82. By pressing the second pusher 16, the bone cement 80 is injected up to the target injection amount. Since the second pusher 16 has a smaller diameter than the first pusher 14, a high pressure can be generated with a small operating force and precise injection is possible. The maximum injection amount of the second pusher 16 may be set to a predetermined amount (for example, 0.5 to 3 mL).

When the injection is suddenly stopped during the injection by the pressing operation of the second pusher 16, the pressing operation on the second pusher 16 may be stopped. Then, since the pressure in the system is surely released, the injection can be stopped suddenly and accurate injection can be ensured.

Next, a second usage method (operation method) of the pharmaceutical injection device 10A will be described with reference to FIGS. 5A to 6B. In the second usage method, as in the first usage method, first, the bone cement 80 is filled into the drug injection device 10A. As shown in FIG. 5A, in the second usage method, it is preferable to use a stopcock 94 in order to prevent the bone cement 80 from being discharged by a rotation operation on the first pusher 14.

The stopcock 94 has a first port 96, a second port 98, and a cock 100. By rotating the cock 100, the passage between the first port 96 and the second port 98 communicates. It is configured as a two-way stopcock that can selectively switch between an open state and a closed state in which the passage between the first port 96 and the second port 98 is blocked. Such a stopcock 94 may be provided at either the end of the extension tube 92 on the side connected to the bone cement injection needle 84 or the end on the side connected to the drug injection tool 10A. As shown in the above, when provided at the end of the side connected to the pharmaceutical injection tool 10A, the cock 94 can be rotated with respect to the cock 100 outside the X-ray irradiation area when the bone cement 80 is injected. X-ray exposure can be suitably avoided.

In this state, the bone cement 80 filled in the drug injection tool 10A is discharged under X-ray fluoroscopy and injected into the bone 82. At the time of this injection operation, in the second usage method, first, as shown in FIG. 5B, the stopcock 94 is opened, the second pusher 16 is pressed, and the second pusher 16 is moved to the cylindrical body. 12 to the tip side. Then, as the second pusher 16 moves toward the distal end side with respect to the first pusher 14, the filling chamber 19 is pressurized to a high pressure, and the bone cement 80 is moved to the distal end tube portion 20, the extension tube 92, and the bone cement injection needle. 84 and injected into the bone 82. Since the second pusher 16 has a smaller diameter than the first pusher 14, a high pressure can be generated with a small operating force and precise injection is possible.

Next, as shown in FIG. 6A, the cock 100 is rotated to close the stopcock 94, and then the second pusher 16 is rotated to move the second pusher 16 toward the distal end side with respect to the cylindrical body 12. Move to. At this time, when the second pusher 16 receives pressure from the bone cement 80, the second pusher 16 moves to the proximal end side with respect to the first pusher 14. In this case, since the bone cement 80 is prevented from being discharged from the drug injection tool 10A by the stopcock 94, the bone cement is discharged from the drug injection tool 10A in accordance with the rotation operation of the first pusher 14. There is no. The rotation operation with respect to the first pusher 14 is performed until the second pusher 16 is retracted to the most proximal position.

Next, as shown in FIG. 6B, after the stopcock 94 is opened, the second pusher 16 is pressed and the bone cement 80 is injected into the bone 82. Thereafter, similarly to the case of FIG. 6A, the first pusher 14 is rotated again to return the second pusher 16 to the original position.

As described above, in the second usage method, the second pusher 16 is rotated by rotating the first pusher 14 after performing an operation of injecting a small amount by pushing the second pusher 16 toward the distal end side. The two operations are alternately repeated a plurality of times to inject the bone cement 80 of the target injection amount. Therefore, precise injection is possible in all injections.

In addition, what is necessary is just to stop the press operation with respect to the 2nd pusher 16, when it wants to stop injection rapidly during the injection | pouring by the press operation of the 2nd pusher 16. FIG. Then, since the pressure in the system is surely released, the injection can be stopped suddenly and accurate injection can be ensured.

In the first usage method and the second usage method of the medicine injection tool 10A described above, the extension tube 92 is used in order to avoid X-ray exposure when the bone cement 80 is injected under X-ray fluoroscopy. For example, when injecting bone cement 80 under CT fluoroscopy, the extension tube 92 is omitted, and the distal end tube portion 20 of the cylindrical body 12 of the drug injection device 10A and the injection port 86 of the bone cement injection needle 84 are directly connected. May be. This also applies to the method of using the pharmaceutical injection device 10B according to the second embodiment described below.

7A, the second pusher 120 according to the modification shown in FIG. 7 may be employed in place of the second pusher 16 in the medicine injection tool 10A. As shown in FIG. 7, the second pusher 120 according to the modification is inserted through the through hole 30 of the first pusher 14 so as to be displaceable in the axial direction within a restricted range. The second pusher 120 includes a rod 122 that is slidably inserted into the through hole 30 of the first pusher 14, and a flange portion 124 that is provided (attached) to the proximal end portion of the rod 122.

The air discharge passage 126 is formed through the rod 122 along the axial direction. A diameter-enlarged portion 128 having a slightly smaller diameter than the through hole 30 of the first pusher 14 is provided at the tip of the rod 122, and an annular groove formed in the outer peripheral portion of the diameter-enlarged portion 128 so as to extend in the circumferential direction. A ring-shaped second seal member 121 is attached. The second seal member 121 is in close contact with the through hole 30, whereby the second pusher 120 can slide in the axial direction in a liquid-tight manner with respect to the first pusher 14 in the through hole 30. It has become.

The base end portion of the rod 122 is configured as a rear end enlarged portion 123 having a larger diameter than the small diameter portion 30 b of the first pusher 14. The rear end enlarged diameter portion 123 is a bottomed cylindrical portion having a cylindrical concave portion 125 opened on the base end side, and an internal thread portion 125a is formed on the inner peripheral portion of the cylindrical concave portion 125, and air discharge The base end of the passage 126 faces the bottom of the cylindrical recess 125. A side hole 127 is formed through the cylindrical recess 125 in the radial direction.

A cylindrical convex portion 129 in which a male screw portion 129a that can be screwed into the female screw portion 125a is formed at the tip of the flange portion 124. The cylindrical convex portion 129 is formed with a passage 140 having one end opened at the front end surface of the cylindrical convex portion 129 and the other end opened at the side surface of the cylindrical convex portion 129. As shown in FIG. 7A, in the state where the flange portion 124 is screwed to the most distal end side with respect to the rod 122, the passage 140 of the cylindrical convex portion 129 and the side hole 127 of the cylindrical concave portion 125 do not communicate with each other. The inside of 12 and the outside do not communicate. That is, the air discharge passage 126 is closed. On the other hand, as shown in FIG. 7B, when the flange portion 124 is rotated by a predetermined angle with respect to the rod 122, the passage 140 of the cylindrical convex portion 129 and the side hole 127 of the cylindrical concave portion 125 communicate with each other. Communication with the outside. That is, the air discharge passage 126 is opened. Thus, the passage 140 of the cylindrical convex portion 129 and the side hole 127 of the cylindrical concave portion 125 constitute an opening / closing means for switching between the open state and the closed state of the air discharge passage 126.

When the second pusher 120 is configured as described above, an air discharge operation is performed after the first pusher 14 to which the second pusher 120 and the guide member 40 are attached is attached to the cylindrical body 12 filled with the bone cement 80. In this case, by rotating the second pusher 120, the inside of the cylinder 12 and the outside can be communicated with each other via the air discharge path 126. Therefore, even if the cylinder 12 is not directed upward, the air discharge path 126 The air in the cylinder 12 can be discharged to the outside.

7A and 7B, a cylindrical concave portion 125 having a female screw portion 125a is provided at the proximal end portion of the rod 122, and a cylindrical convex portion 129 having a male screw portion 129a is provided at the distal end portion of the flange portion 124. Although provided, the male and female of the screw may be reversed. That is, a cylindrical convex portion having a male screw portion may be provided at the base end portion of the rod 122, and a cylindrical concave portion having a female screw portion may be provided at the distal end portion of the flange portion 124.

[Second Embodiment]
FIG. 8 is a longitudinal sectional view of a pharmaceutical injection device 10B according to the second embodiment of the present invention. Similarly to the drug injection tool 10A according to the first embodiment, the drug injection tool 10B is an instrument used for discharging a drug when a drug (filler, injection material) is injected into a desired injection space. . As shown in FIG. 8, the drug injection device 10 </ b> B includes a hollow cylindrical body 102, a first pusher 104 inserted into the cylindrical body 102, and a second pusher 106 inserted into the first pusher 104. Is provided.

The cylindrical body 102 includes a body portion 108 having a lumen (hollow portion) extending in the axial direction, and a distal end tube portion 110 protruding from the distal end portion of the body portion 108 toward the distal end side, and the overall shape is cylindrical. It is the member which makes. The body portion 108 and the distal end tube portion 110 are integrally formed.

The body portion 108 includes a small diameter portion 112 constituting the front end side, and a large diameter portion 114 constituting the rear end side and having an inner diameter and an outer diameter larger than the small diameter portion 112. The axes of the small diameter portion 112 and the large diameter portion 114 coincide. The internal volume of the small diameter portion 112 is set to about 1 to 3 mL, and the internal volume of the large diameter portion 114 is set to about 5 to 20 mL. On the inner peripheral surface of the large diameter portion 114, an internal thread portion 116 is formed over a predetermined range in the axial direction. A scale similar to the scale 24 shown in FIG. 1 is provided on the outer peripheral surface of the large diameter portion 114.

The tip tube portion 110 is a tubular portion having a reduced diameter with respect to the small diameter portion 112, and is configured in the same manner as the tip tube portion 20 shown in FIG. Further, a lock portion 111 similar to the lock portion 28 shown in FIG. 1 is provided at the tip of the small diameter portion 112.

The constituent material of the cylinder 102 can be selected from the materials exemplified as the constituent material of the cylinder 12 described above. In the cylindrical body 102 configured as described above, a filling chamber 107 for filling a medicine is formed by a space surrounded by the cylindrical body 102, the first pusher 104 and the second pusher 106. .

The first pusher 104 is inserted into the hollow portion of the cylindrical body 102, and has a circular through-hole 118 penetrating linearly in the axial direction. The inner diameter (size) of the through hole 118 is constant along the axial direction. A head 140 having an enlarged diameter is provided at the tip of the first pusher 104, and a screw thread 116 formed on the inner peripheral surface of the cylindrical body 102 is screwed to the outer peripheral surface of the head 140. A mating male screw portion 122 is formed. That is, the feed screw structure 144 that displaces the first pusher 104 in the axial direction with respect to the cylindrical body 102 by the rotation of the first pusher 104 with respect to the cylindrical body 102 by the female screw portion 116 and the male screw portion 142. It is configured.

A handle 146 having an enlarged diameter is provided on the outer periphery of the proximal end of the first pusher 104. When the first pusher 104 is rotated with respect to the cylindrical body 102, the handle 146 can be held and rotated. When the second pusher 106 is moved relative to the first pusher 104, that is, when the second pusher 106 is pressed, the handle 146 is operated with a finger. be able to.

The second pusher 106 is inserted into the through hole 118 of the first pusher 104 so as to be freely displaceable in the axial direction within a restricted range. The second pusher 106 includes a rod 131 having a circular cross section that is longer and smaller in diameter than the first pusher 104, and a flange portion 130 provided at the proximal end of the rod 131. The outer diameter of the rod 131 is smaller than the outer diameter of the head 140 of the first pusher 104. In addition, the outer diameter of the rod 131 is set to be substantially the same as the inner diameter of the through hole 118, so that when the first pusher 104 is pressed against the second pusher 106, the outer peripheral surface of the rod 131. And the inner peripheral surface of the through hole 118 slide in close contact with each other.

Of the rod 131, the second pusher 106 is displaced to the most proximal side with respect to the first pusher 104, and the second pusher is placed on the outer peripheral surface of the portion protruding from the first pusher 104 to the proximal side. Scales 132 indicating the position (pushing amount, insertion amount) in the axial direction with respect to the child 106 are provided at regular intervals. The scale 132 is not particularly limited as long as it can be visually recognized by the user. The scale 132 may be formed by a groove extending in the circumferential direction, or displayed by ink (paint) having a color different from that of the rod 131. It may be.

A rib 134 (protrusion) protruding outward (radially outward) is provided on the outer periphery of the tip of the rod 131. Although a plurality (two) of ribs 134 according to the illustrated configuration example are provided in the circumferential direction, only one rib 134 may be provided in the circumferential direction. The rib 134 may be formed integrally with the rod 131, or may be formed as a separate member from the rod 131 and fixed by adhesion, heat fusion, or the like.

In addition, the rib 134 according to the illustrated configuration example is configured to partially protrude in the circumferential direction on the outer peripheral portion of the rod 131, but in an annular shape (flange shape) extending over the entire circumference (360 °) in the circumferential direction. It may be configured. The outer diameters of the rod 131 and the rib 134 are smaller than the inner diameter of the small-diameter portion 112, so that the second pusher 106 has a small diameter in a state where the first pusher 104 moves to the distal end side with respect to the cylindrical body 102. It can be inserted into the lumen of the portion 112.

The second pusher 106 moves to the proximal end side with respect to the first pusher 104 to a position where the proximal end surface of the rib 134 and the distal end surface of the first pusher 104 (the distal end surface 140a of the head 140) abut. be able to. In other words, in the present embodiment, the second pusher 106 is regulated by the proximal end surface of the rib 134 and the distal end surface 140a of the head 140 to restrict the position where the second pusher 106 is displaced most proximally with respect to the first pusher 104. Positioning means 136 is configured.

The flange portion 130 is a portion that the user presses with a finger (for example, a thumb) when pressing the second pusher 106 toward the distal end side, and has an appropriate size so that it can be easily pressed. The flange portion 130 is fitted and connected to the proximal end portion of the rod 131. The connection structure by fitting the rod 131 and the flange portion 130 may be either screw fitting or uneven fitting (taper fitting). In addition, the connection structure of the rod 131 and the flange part 130 material is not limited to the fitting structure, and may be a structure fixed by adhesion, heat fusion, or the like.

The second pusher 106 can move relative to the first pusher 104 to a position where the distal end surface 130a of the flange portion 130 and the proximal end surface 126a of the handle 146 come into contact with each other. In other words, in the present embodiment, the position where the second pusher 106 is displaced to the most distal side with respect to the first pusher 104 is regulated by the distal end surface 130 a of the flange portion 130 and the proximal end surface 126 a of the handle 146. One positioning means 138 is configured.

The constituent materials of the rod 131 and the flange portion 130 can be selected from those exemplified as the constituent materials of the cylindrical body 12 of the pharmaceutical injection device 10A according to the first embodiment described above.

The drug injection device 10B according to the second embodiment of the present invention is basically configured as described above, and hereinafter, the drug injection device 10B is percutaneously subjected to percutaneous vertebroplasty for its action and effect. The case of using in FIG.

First, the first usage method (operation method) of the pharmaceutical injection device 10B will be described. As shown in FIG. 9A, a predetermined amount (for example, 5 to 20 mL) of bone cement 80 is filled in the filling chamber 107 in advance. Next, the cylindrical body 102 of the drug injection tool 10 </ b> B and the injection port 86 of the bone cement injection needle 84 pierced into the bone 82 to be injected with the bone cement 80 are connected via the extension tube 92.

In this state, the bone cement 80 filled in the drug injection tool 10B is discharged under X-ray fluoroscopy and injected into the bone 82. In this injection operation, in the first method of using the drug injection device 10B, first, as shown in FIG. 9B, the first pusher 104 is rotated and moved to the distal end side with respect to the cylindrical body 102. Then, as the first pusher 104 moves toward the distal end side with respect to the cylindrical body 102, the filling chamber 107 is pressurized to a high pressure, and the bone cement 80 moves the distal end pipe portion 110, the extension tube 92, and the bone cement injection needle 84. And injected into the bone 82. Since the movement of the first pusher 104 toward the distal end side can be performed by a rotating operation, the bone cement 80 can be injected with a relatively small operation force, and the first pusher 104 has a relatively large diameter. A relatively large amount of bone cement 80 can be rapidly injected.

After the bone cement 80 has been injected to the approximate target injection amount by the rotation operation with respect to the first pusher 104, the second pusher 106 is then pressed to bring the first pusher 104 into the first pusher 104 as shown in FIG. On the other hand, it moves to the tip side. Then, as the second pusher 106 moves toward the distal end side with respect to the first pusher 104, the filling chamber 107 is pressurized to a high pressure, and the bone cement 80 is moved to the distal end pipe portion 110, the extension tube 92, and the bone cement injection needle. 84 and injected into the bone 82. By pressing the second pusher 106, the bone cement 80 is injected up to the target injection amount. Since the second pusher 106 has a smaller diameter than the first pusher 104, a high pressure can be generated with a small operating force, and precise injection is possible.

When it is desired to stop the injection suddenly during the injection by the pressing operation of the second pusher 106, the pressing operation on the second pusher 106 may be stopped. Then, since the pressure in the system is surely released, the injection can be stopped suddenly and accurate injection can be ensured.

Next, a second usage method (operation method) of the pharmaceutical injection device 10B will be described with reference to FIGS. 11A to 12B. In the second usage method, as in the first usage method, first, the bone cement 80 is filled into the drug injection device 10B. As shown in FIG. 11A, in the second usage method, it is preferable to use a stopcock 94 in order to prevent the bone cement 80 from being discharged by a rotation operation on the first pusher 104. This stopcock 94 is the same as the stopcock 94 shown in FIG. 5A and the like.

The stopcock 94 may be provided at either one end or the other end of the extension tube 92. However, as shown in FIG. 11A and the like, when the stopcock 94 is provided at the end connected to the drug injection device 10B, The operation of the stopcock can be performed outside the X-ray irradiation region at the time of injection, and X-ray exposure can be suitably avoided.

In this state, the bone cement 80 filled in the drug injection tool 10B is discharged under X-ray fluoroscopy and injected into the bone 82. At the time of this injection operation, in the second usage method, first, as shown in FIG. 11B, the stopcock 94 is opened and the second pusher 106 is pressed to move the distal end side with respect to the cylindrical body 102. I will move to. Then, as the second pusher 106 moves toward the distal end side with respect to the first pusher 104, the filling chamber 107 is pressurized to a high pressure, and the bone cement 80 is moved to the distal end pipe portion 110, the extension tube 92, and the bone cement injection needle. 84 and injected into the bone 82. Since the second pusher 106 has a smaller diameter than the first pusher 104, a high pressure can be generated with a small operating force, and precise injection is possible.

The medicine injection tool 10B is configured such that when the second pusher 106 is operated, the second pusher 106 protrudes from the tip of the first pusher 104, but the second pusher 106 is formed on the small diameter portion 112 of the cylindrical body 102. Since insertion is possible, dead volume is suppressed, and it is possible to efficiently inject the bone cement 80 using the stroke of the second pusher 106 to the maximum extent.

Next, as shown in FIG. 12A, the cock 100 is rotated to close the stopcock 94, and then the second pusher 106 is rotated to move the tube 102 toward the distal end. At this time, when the second pusher 106 receives pressure from the bone cement 80, the second pusher 106 moves to the proximal end side with respect to the first pusher 104. In this case, since the bone cement 80 is prevented from being discharged from the drug injection tool 10B by the stopcock 94, the bone cement 80 is discharged from the drug injection tool 10B as the first pusher 104 is rotated. There is nothing. The rotation operation with respect to the first pusher 104 is performed until the second pusher 106 is retracted to the most proximal position with respect to the first pusher 104.

Next, as shown in FIG. 12B, after the stopcock 94 is in the open state, the second pusher 106 is pressed to inject the bone cement 80 into the bone 82. Thereafter, similarly to the case of FIG. 12A, the first pusher 104 is rotated again to return the second pusher 106 to the original position.

As described above, in the second operation method, the second pusher 106 is rotated by rotating the first pusher 104 after performing an operation of injecting a small amount by pushing the second pusher 106 toward the distal end side. Is returned to the original position, and these two operations are alternately repeated a plurality of times to inject a bone cement of a target injection amount. Therefore, precise injection is possible in all injections.

In addition, what is necessary is just to stop the press operation with respect to the 2nd pusher 106, when you want to stop injection rapidly during the injection | pouring by the press operation of the 2nd pusher 106. Then, since the pressure in the system is surely released, the injection can be stopped suddenly and accurate injection can be ensured.

In the medicine injection device 10B according to the second embodiment, the air push-out passage 126 is provided in the second pusher 106 in the same manner as the second pusher 120 according to the modification shown in FIGS. 7A and 7B. Side holes 127 and passages 140 are respectively provided in the portion 130 so that they can be screwed together, and the flange portion 130 is rotated with respect to the rod 131 so that the inside and outside of the cylinder 102 are connected via the air discharge passage 126. It is good also as a structure which can be communicated.

[Third Embodiment]
FIG. 13 is a perspective view showing a pharmaceutical injection device 10C according to the third embodiment of the present invention. FIG. 14 is a longitudinal sectional view of the pharmaceutical injection device 10C shown in FIG. Similarly to the drug injection tool 10A according to the first embodiment, the drug injection tool 10C is an instrument used for discharging a drug when a drug (filler, injection material) is injected into a desired injection space. . As shown in FIG. 13, the drug injection device 10C includes a hollow cylindrical body 150, a first pusher 152 inserted into the cylindrical body 150, a guide member 154 through which the first pusher 152 is inserted, And a second pusher 156 inserted into the first pusher 152.

The cylindrical body 150 includes a body portion 158 having a lumen (hollow portion) extending in the axial direction, and a distal end tube portion 160 protruding from the distal end portion of the body portion 158 to the distal end side, and the overall shape is cylindrical. It is the member which makes. The body portion 158 and the tip tube portion 160 are integrally formed.

The body portion 158 is formed in a hollow cylindrical shape whose inner diameter is substantially constant along the axial direction, and a scale 151 indicating the amount of the drug is displayed on the outer peripheral surface thereof. The internal volume of the body portion 158 is set to about 5 to 20 mL.

The tip tube portion 160 is a tubular portion having a reduced diameter with respect to the body portion 158, and an internal thread portion 161 is formed on the inner peripheral surface thereof. The distal end tube portion 160 having the female screw portion 161 can be connected to the extension tube 92 via a connector 216 (see FIG. 17A) described later. On the outer periphery of the base end portion of the body portion 158, a male screw portion 159 for screwing with the guide member 154 is formed. The constituent material of the cylindrical body 150 can be selected from the materials exemplified as the constituent material of the cylindrical body 12 described above.

Inside the cylinder 150 configured as described above, a filling chamber 153 for filling a medicine is formed by a space surrounded by the cylinder 150, the first pusher 152, and the second pusher 156. .

The first pusher 152 is inserted into the hollow portion of the cylindrical body 150 so as to be slidable in a liquid-tight manner. Specifically, the first pusher 152 includes a pusher main body 162 that can be inserted into the hollow portion of the cylindrical body 150, an annular ring member 164 provided on the outer periphery of the distal end portion of the pusher main body 162, and the ring. And an annular first seal member 166 attached to the outer periphery of the member 164.

The pusher main body 162 includes a first rod 168 that can be inserted into the hollow portion of the cylindrical body 150, and a handle 170 that is provided at the base end of the first rod 168 and has a diameter increased outward (radially outward). An external thread portion 169 is formed along the axial direction in a predetermined range in the longitudinal direction on the outer peripheral portion of the first rod 168. The outer diameter of the male screw portion 169 is smaller than the inner diameter of the body portion 158 of the cylindrical body 150.

A cylindrical tip tube portion 168a to which the ring member 164 is attached is provided at the tip portion of the first rod 168. The outer diameter of the tip tube portion 168a is smaller than the outer diameter of the male screw portion 169. As shown in FIG. 15, an annular convex portion 168b is provided on the outer peripheral portion of the distal end cylindrical portion 168a.

The handle 170 is a portion that the user grips (pinch) with the fingers when the first pusher 152 is rotated about the axis with respect to the cylindrical body 150. In the present embodiment, the handle 170 is the first rod 168. The second pusher 156 protruding from the proximal end extends in the proximal direction so as to cover at least partially. Specifically, the handle 170 has a flange portion 170a that extends radially outward from the proximal end portion of the first rod 168, and a cover portion 170b that extends in the proximal direction from the outer end of the flange portion 170a. A plurality of grooves 171 (see FIG. 13) are formed on the outer periphery of the cover part 170b at intervals in the circumferential direction so that it is difficult to slip when the user grips and rotates. The length of the cover portion 170b along the axial direction is set so that the user's fingers do not come into contact with the second pusher 156 when the user grips the handle 170, for example, 30 to 100 mm. About 50 to 80 mm, preferably about 50 to 80 mm.

The handle 170 (specifically, the cover portion 170b) is provided with a cutout portion 172 that extends along the axial direction of the second pusher 156 and is opened in the proximal direction of the handle 170. In the present embodiment, two notches 172 are provided at symmetrical positions (positions that are 180 degrees out of phase) with respect to the center (axis) of the first rod 168.

The width H of the notch portion 172 is set so that the user can easily press the second pusher 156 when the second pusher 156 is moved in the distal direction with respect to the first pusher 152. It is preferable that the finger is inserted so that the finger can be inserted. For example, the finger is set to about 20 to 35 mm, and preferably about 25 to 30 mm. Further, as shown in FIG. 14, the notch 172 extends to the vicinity of the tip of the handle 170 so that the user can easily insert the finger into the notch 172 and advance the second pusher 156 to the maximum. It is good to be.

The first pusher 152 is provided with a through-hole 174 that passes through the first rod 168 and the handle 170 linearly in the axial direction. The through hole 174 includes a large diameter portion 174 a that forms the distal end side of the through hole 174 and a small diameter portion 174 b that forms the proximal end side of the through hole 174. In the configuration example of FIG. 14, the stepped portion 175 that is the boundary between the large diameter portion 174 a and the small diameter portion 174 b is set at a position slightly proximal to the intermediate point in the axial direction of the first rod 168. .

The ring member 164 is disposed concentrically with the first rod 168 and is fitted to the outer side of the distal end cylindrical portion 168a of the first rod 168 so as to be relatively rotatable with respect to the first rod 168. As shown in FIG. 15, an annular recess 164 a is provided on the inner peripheral portion of the ring member 164. Relative movement in the axial direction between the ring member 164 and the tip tube portion 160 is prevented by the engagement of the ring-shaped convex portion 168b provided in the tip tube portion 160 and the ring-shaped recess portion 164a provided in the ring member 164. .

An annular seal groove 164b is formed on the outer periphery of the ring member 164, and a ring-shaped first seal member 166 (for example, a silicone O-ring or the like) is disposed in the seal groove 164b. In a state where the first rod 168 of the first pusher 152 is inserted into the cylindrical body 150, the outer peripheral portion of the first seal member 166 and the inner peripheral surface of the cylindrical body 150 are in close contact. As a result, the first pusher 152 can slide in a liquid-tight manner inside the cylindrical body 150.

The first pusher 152 is inserted through the guide member 154. The guide member 154 is cylindrical (both cylindrical in the illustrated example) with both ends open, and is formed with a first female screw portion 154a and a second female screw portion 154b. The first female screw portion 154a can be screwed into a male screw portion 159 formed on the outer peripheral portion of the base end of the outer cylinder. That is, the guide member 154 can be attached to and detached from the cylindrical body 150 by screw fitting. The second female screw portion 154 b has a smaller diameter than the first female screw portion 154 a and is screwed into a male screw portion 169 formed on the outer peripheral portion of the first rod 168.

By inserting the first rod 168 of the first pusher 152 from the proximal end opening of the cylindrical body 150 and screwing the guide member 154 screwed to the first rod 168 to the proximal end portion of the cylindrical body 150, As shown in FIG. 14, the cylindrical body 150 and the first pusher 152 are connected via the guide member 154 in a state where the first pusher 152 is inserted into the hollow portion of the cylindrical body 150. In this connected state, when the first pusher 152 is relatively rotated around the axis with respect to the cylindrical body 150, the first pusher 152 is moved under the screwing action of the second female screw part 154b and the male screw part 169. The cylinder body 150 is displaced in the distal direction or the proximal direction. That is, the feed screw structure that causes the first pusher 152 to be displaced in the axial direction with respect to the cylindrical body 150 by the rotation of the first pusher 152 with respect to the cylindrical body 150 by the second female screw part 154b and the male screw part 169. 180 is configured.

The second pusher 156 is inserted into the through hole 174 of the first pusher 152 so as to be freely displaceable in the axial direction within a restricted range. The second pusher 156 has a smaller diameter than the first rod 168 and is slidably inserted into the through hole 174 of the first pusher 152, and the tip of the second rod 182. It has the 2nd seal member 184 provided in the outer periphery (attached), and the flange part 186 provided in the base end part of the 2nd rod 182 (attached).

A scale 64 similar to the scale 64 shown in FIG. 1 is provided at regular intervals on the outer peripheral surface on the proximal end side of the second rod 182. A diameter-expanded portion 182a having an outer diameter slightly larger than the proximal end portion is formed at the distal end portion of the second rod 182. A step portion 185 is formed by a difference in outer diameter between the enlarged diameter portion 182a and a portion closer to the proximal end than the enlarged diameter portion (hereinafter referred to as a narrow diameter portion 182b).

The second pusher 156 is moved to the position where the end surface (step 185) on the proximal end side of the enlarged diameter portion 184a and the step 175 provided on the inner peripheral portion of the first pusher 152 come into contact with each other. It can move to the base end side with respect to the child 152. That is, in this embodiment, the step 175 and the step 185 constitute the second positioning means 188 that regulates the position where the second pusher 156 is displaced to the most proximal side with respect to the first pusher 152. Yes.

The second seal member 184 is formed in a ring shape, and the outer peripheral portion of the second seal member 184 and the inner peripheral surface of the first rod 168 (through hole 174) are in close contact with each other. As a result, the first pusher 152 can slide in a liquid-tight manner inside the cylindrical body 150. The seal member attached to the second rod 182 is a bottomed member attached to the tip of the second rod 182 instead of the ring-shaped second seal member 184 attached to the tip of the second rod 182. It may be a cylindrical seal member (see the second seal member 60 in FIG. 1). The stroke (displacement length) of the second pusher 156 relative to the first pusher 152 is set to about 25 to 100 mm.

When the second pusher 156 is displaced to the most proximal side with respect to the first pusher 152, the inner volume of the through-hole 174 on the distal end side relative to the second pusher 156 (that is, the medicine in the medicine injection tool 10C) The amount of medicine discharged by the second pusher 156 when the second pusher 156 is moved from the most proximal side to the most distal side with respect to the first pusher 152 in a state filled with Set to about 3 mL. The flange portion 170 a has the same configuration as the flange portion 170 a shown in FIG. 2 and the like, and is fitted and connected to the base end portion of the second rod 182.

The second pusher 156 can move relative to the first pusher 152 to a position where the distal end surface 186a of the flange portion 186 and the proximal end surface 170c of the flange portion 170a of the handle 170 abut. That is, in the present embodiment, the position where the second pusher 156 is displaced to the most distal side with respect to the first pusher 152 by the distal end surface 186 a of the flange portion 186 and the proximal end surface 170 c of the flange portion 170 a of the handle 170. 1st positioning means 190 which regulates is constituted. In the illustrated example, when the second pusher 156 moves to the most distal side with respect to the first pusher 152, the most distal portion of the second pusher 156 substantially coincides with the most distal portion of the first pusher 152. .

In the medicine injection tool 10C, the tip of the second pusher 156 is located in the through hole 174 of the first pusher 152 regardless of the position of the second pusher 156 within the movable range.

The drug injection device 10C configured as described above is the same as the first operation method shown in FIGS. 3A to 4 or the second operation method shown in FIGS. 5A to 6B with respect to the drug injection device 10A. Can be operated (used). That is, in the operation of injecting bone cement, the bone cement can be precisely injected by combining the rotation operation with respect to the first pusher 152 and the pressing operation with respect to the second pusher 156.

In the case of this embodiment, the handle 170 extends in the proximal direction so as to at least partially cover the second pusher 156 protruding from the proximal end of the first rod 168. When the first pusher 152 is moved in the distal direction relative to the cylindrical body 150 by rotating the 152, the user's finger is prevented from coming into contact with the second pusher 156. That is, when the user grips the handle 170, even if the second pusher 156 moves to the proximal end side with respect to the first pusher 152, the relatively large cover portion 170 b provided on the handle 170. Is interposed between the user's finger and the second pusher 156, so that the user's finger does not contact the second pusher 156. Therefore, the operability when rotating the first pusher 152 is excellent.

Furthermore, in the case of this embodiment, the cover portion 170b of the handle 170 is provided with a cutout portion 172 extending in the axial direction and opened in the proximal direction, so that the user inserts a finger into the cutout portion 172 Then, a pressing operation on the second pusher 156 can be performed through the notch 172. Therefore, the cover portion 170b does not get in the way during the pressing operation on the second pusher 156, and the pressing operation can be performed smoothly.

Furthermore, in the present embodiment, since the guide member 154 and the cylinder 150 can be connected by screw fitting, the guide member 154 is connected to the cylinder 150 in a state where the guide member 154 and the cylinder 150 are connected. It is supported on the entire circumference of the outer periphery of the base end. Therefore, the coupling strength between the guide member 154 and the cylindrical body 150 can be effectively increased, and the durability of the coupling portion can be improved.

Furthermore, in the case of this embodiment, the ring member 164 is provided at the distal end portion of the first rod 168 so as to be rotatable relative to the first rod 168. Therefore, when the first pusher 152 is rotated. The ring member 164 does not rotate with respect to the cylindrical body 150, and only the pusher main body 162 rotates with respect to the cylindrical body 150. That is, even if the pusher main body 162 rotates, the ring member 164 rotates with respect to the cylindrical body 150 by the frictional resistance between the first seal member 166 attached to the outer peripheral portion thereof and the inner peripheral surface of the cylindrical body 150. There is no. Therefore, no sliding resistance in the circumferential direction is generated between the first seal member 166 and the inner peripheral surface of the cylindrical body 150, and the operation force necessary to rotate the first pusher 152 is effectively reduced. It can be used and has excellent operability.

In the case of the present embodiment, the first pusher 152 to which the ring member 164 is attached and the second pusher 156 is inserted after the bone cement is filled from the proximal end side of the cylindrical body 150 is attached to the cylindrical body 150. When the first pusher 152 is moved in the distal direction, the air in the cylindrical body 150 is discharged to the outside through a slight gap between the inner peripheral surface of the ring member 164 and the outer peripheral surface of the distal end cylindrical portion 168a. Can do. Therefore, even when the bone cement is filled from the proximal end side of the cylindrical body 150, the air discharging operation can be performed easily and quickly.

[Fourth Embodiment]
FIG. 16 is a longitudinal sectional view of a pharmaceutical injection device 10D according to the fourth embodiment of the present invention. The drug injection device 10D according to the present embodiment is different from the drug injection device 10C according to the third embodiment with respect to the configuration of the first pusher 200 and the second pusher 202. Therefore, in the medicine injection device 10D, the same reference numerals are given to the same components as those of the medicine injection device 10C, and duplicate descriptions are omitted.

The first pusher 200 includes a pusher main body 204 that can be inserted into the hollow portion of the cylindrical body 150, an annular ring member 164 provided on the outer periphery of the distal end portion of the pusher main body 204, and an outer peripheral portion of the ring member 164. And an annular first seal member 166 attached to the. The ring member 164 and the first seal member 166 have the same configuration as the ring member 164 and the first seal member 166 shown in FIG. The pusher body 204 includes a first rod 206 that can be inserted into the hollow portion of the cylindrical body 150, and a handle 208 that is provided at the proximal end portion of the first rod 206 and has an outer diameter (outward in the radial direction). .

As will be described later, the second pusher 202 serves to quickly release the pressure in the system by sliding in the proximal direction with respect to the first pusher 200 when the injection of bone cement is stopped. The stroke (displacement length, movable range) of the second pusher 202 with respect to the first pusher 200 is set within a range necessary for exhibiting the action. The stroke of the second pusher 202 relative to the first pusher 200 is set to be, for example, about 30 to 100 mm, or equivalent to a volume change of 0.3 to 3.0 mL. In the present embodiment, the step portion 175 that is the boundary between the large diameter portion 174 a and the small diameter portion 174 b of the through hole 174 of the first rod 206 is slightly closer to the tip than the intermediate point in the axial direction of the first rod 206. In the position.

The handle 208 is a portion that a user grips (pinch) with fingers when rotating the first pusher 200 about the axis with respect to the cylindrical body 150, and has a cross-section so that the user can easily grip it. Is formed in a substantially circular shape. In the present embodiment, the handle 208 is provided with a recess 210 that opens in the proximal direction and into which the flange portion 214 of the second pusher 202 can be inserted. The recess 210 is disposed on the axis of the first pusher 200, and the base end side opening of the through hole 174 through which the second pusher 202 is inserted and guided is opened at the bottom 210 a of the recess 210. . When the user grips the handle 208 so that the base end of the handle 208 touches the palm, the recess 210 is closed by the palm.

The second pusher 202 is inserted through the through hole 174 of the first pusher 200 so as to be freely displaceable in the axial direction within a restricted range. The second pusher 202 has a smaller diameter than the first rod 206 and is slidably inserted into the through hole 174 of the first pusher 200, and the tip of the second rod 212. It has the 2nd seal member 184 provided in the outer periphery (attached), and the flange part 214 provided (attached) in the base end part of the rod.

The second rod 212 is longer than the second rod 212 shown in FIG. 14, but the other parts are the same as the second rod 212. The second seal member 184 is the same as the second seal member 184 shown in FIG. The flange portion 214 has a base end surface formed in a convex curved surface so that the surface pressure of the contact portion when pressed against the palm of the user by pressing force from the bone cement in the base end direction can be reduced. The configuration of other portions of the flange portion 214 is the same as that of the flange portion 186 shown in FIG.

The second pusher 202 can move with respect to the first pusher 200 to a position where the front end surface 214a of the flange portion 214 and the bottom portion 210a of the concave portion 210 of the handle 208 come into contact with each other. That is, in the present embodiment, the position where the second pusher 202 is displaced to the most distal side with respect to the first pusher 200 is regulated by the front end surface 214a of the flange portion 214 and the bottom portion 210a of the recess 210. Positioning means 211 is configured.

Next, an operation method (usage method) of the pharmaceutical injection device 10D configured as described above will be described. The first pusher 200 is inserted into the cylindrical body 150, the guide member 154 is connected to the outside of the cylinder, and the drug injection tool 10D in which the filling chamber 151 is filled with bone cement is punctured into the bone 82 via the extension tube 92. The bone cement injection needle 84 is connected to the injection port 86 (see FIG. 17A). Note that a connector 216 that can be screw-fitted to the distal end tube portion 160 of the cylindrical body 150 is provided at one end portion of the extension tube 92. The second pusher 202 is moved in the distal direction with respect to the first pusher 200 to a position where the flange portion 214 is immersed in the recess 210 provided in the handle 208.

Then, the handle 208 is gripped so that the proximal end side of the handle 208 of the first pusher 200 is covered with a palm, and the first pusher 200 is rotated to operate the first pusher 200 with respect to the cylindrical body 150. And move it toward the tip. At this time, the second pusher 202 is subjected to a force to move the first pusher 200 in the proximal direction by the pressure from the bone cement 80 in the cylindrical body 150. 202 is prevented from moving in the proximal direction by coming into contact with the palm of the user. As a result, as shown in FIG. 17A, the first pusher 200 and the second pusher 202 move integrally with the cylindrical body 150 in the distal direction.

Then, as the first pusher 200 moves toward the distal end side with respect to the cylindrical body 150, the filling chamber 151 is pressurized to a high pressure, and the bone cement 80 moves the distal end pipe portion 160, the extension tube 92, and the bone cement injection needle 84 together. And injected into the bone 82. Since the movement of the first pusher 200 toward the distal end side can be performed by a rotating operation, the bone cement 80 can be injected with a relatively small operation force, and the first pusher 200 has a relatively large diameter. A relatively large amount of bone cement 80 can be rapidly injected.

When the bone cement 80 is injected to the target injection amount by the rotation operation with respect to the first pusher 200, or when it is desired to stop the injection of the bone cement 80 suddenly, the grasping of the handle 208 of the first pusher 200 is immediately released. That is, the hand is released from the handle 208. Then, since the action of preventing the movement of the second pusher 202 in the proximal direction by the palm of the user is released, as shown in FIG. 17B, the second pusher 202 is caused by the pressure from the bone cement 80. The first pusher 200 moves in the proximal direction by an amount corresponding to the pressure remaining in the system. As a result, the pressure in the system is reliably released, so that the injection can be stopped reliably and a precise injection can be performed.

The drug injection device 10D can be used in the same manner as the first use method shown in FIGS. 3A to 4 or the second use method shown in FIGS. 5A to 6B with respect to the drug injection device 10A. . That is, in the operation of injecting the bone cement 80, the bone cement 80 can be precisely injected by combining the rotation operation with respect to the first pusher 200 and the pressing operation with respect to the second pusher 202.

In addition, in 4th Embodiment, about each component which is common in 1st and 3rd embodiment, the operation | movement which is the same as that of the said each common component in 1st and 3rd embodiment, and the effect which are the same, or the same effect Of course, the effect is obtained.

[Fifth Embodiment]
FIG. 18 is a longitudinal sectional view of a pharmaceutical injection device 10E according to the fifth embodiment of the present invention. The drug injection device 10E according to the present embodiment corresponds to a modification of the drug injection device 10E according to the fourth embodiment, and the configuration of the first pusher 220 and the second pusher 222 is the fourth embodiment. This is different from the pharmaceutical injection device 10D according to the above. Therefore, in the medicine injection device 10E, the same reference numerals are given to the same components as those of the medicine injection device 10D, and the duplicate description is omitted.

In the present embodiment, the first pusher 220 and the second pusher 222 are fitted such that they can be displaced relative to each other in the axial direction within a restricted range and cannot rotate relative to each other. The first pusher 220 includes a pusher main body 224 that can be inserted into the hollow portion of the cylindrical body 12, an annular ring member 164 provided on the outer periphery of the distal end portion of the pusher main body 224, and an outer peripheral portion of the ring member 164. And an annular first seal member 166 attached to the.

The pusher body 224 is configured to be insertable into the hollow portion of the cylindrical body 12 and has a portion corresponding to the first rod 206 shown in FIG. 16 but does not have a portion corresponding to the handle 208. The pusher main body 224 is provided with a male screw portion 169 and a tip cylindrical portion 168a similar to the male screw portion 169 and the tip cylindrical portion 168a provided on the pusher main body 162 shown in FIG. As shown in FIG. 19A, which is a cross-sectional view taken along the line XIXA-XIXA in FIG. 18, the pusher body 224 is provided along the axial direction on the outer peripheral portion of the portion 226 on the base end side from the male screw portion 169. A plurality of concave grooves 227 are formed at intervals in the circumferential direction.

The second pusher 222 is inserted into the through hole 174 of the first pusher 220 so as to be freely displaceable in the axial direction within a restricted range. The second pusher 222 includes a rod 228 slidably inserted into the through hole 174 of the first pusher 220, and a ring-shaped second seal member provided (attached) on the outer periphery of the distal end portion of the rod 228. 184, a handle 230 provided (attached) at the base end portion of the rod 228 and radially outward from the base end portion of the rod 228, and a relative rotation with respect to the base end portion of the rod 228 provided at the handle 230 And a fitting portion 232 to be fitted into the.

The rod 228 has the same configuration as the second rod 212 shown in FIG. The handle 230 is a portion that is gripped and rotated by the user, and has an appropriate size (outer diameter and length) so that the user can easily grip it. The handle 230 is provided with a recess 231 that opens in the distal direction.

The second pusher 222 can move with respect to the first pusher 220 to a position where the bottom 231a of the recess 231 and the proximal end surface 224a of the pusher main body 224 come into contact with each other. That is, in the present embodiment, the position where the second pusher 222 is displaced to the most distal side with respect to the first pusher 220 is regulated by the bottom 231a of the recess 231 and the base end surface 224a of the pusher body 224. One positioning means 235 is configured.

In the present embodiment, the fitting portion 232 is configured in a hollow cylindrical shape that extends from the bottom of the recess 231 in the distal direction. As shown in FIG. 19A, a plurality of protrusions 234 that engage (fit) into the groove 227 and extend along the axial direction are spaced apart in the circumferential direction on the inner peripheral portion of the fitting portion 232 (illustrated example). There are four). The first pusher 220 and the second pusher 222 can be displaced relative to each other in the axial direction by the engaging action of the concave groove 227 and the protrusion 234, but they are fitted so as not to be relatively rotatable in the circumferential direction. ing.

As described above, in this embodiment, the concave groove 227 and the protrusion 234 constitute a fitting structure that allows relative displacement between the first pusher 220 and the second pusher 222 and restricts relative rotation. . In FIG. 19A, the pusher main body 224 is provided with the concave groove 227 and the fitting portion 232 is provided with the protrusion 334, but the fitting male and female may be reversed. That is, a protrusion may be provided on the outer peripheral portion of the pusher main body 224, and a concave groove that engages with the protrusion may be provided on the inner peripheral portion of the fitting portion 232.

Instead of or in addition to the fitting structure formed by the concave groove 227 and the protrusion 234, a protrusion 236 extending along the axial direction is provided on the outer peripheral portion of the rod 228, and the pusher body 224 is provided. A groove 238 extending in the axial direction and engaging (fitting) with the protrusion 236 is provided on the inner peripheral portion of the protrusion 236, and another fitting structure is constituted by the protrusion 236 and the groove 238. Good. FIG. 19B is a cross-sectional view taken along line XIXB-XIXB in FIG. 18 when such protrusions 236 and concave grooves 238 are provided. Plural ridges 236 and concave grooves 238 may be provided at intervals in the circumferential direction. In FIG. 19B, the groove 238 is provided in the inner peripheral portion of the pusher body 224, and the protrusion 236 is provided in the outer peripheral portion of the rod 228. Also good. That is, a concave groove may be provided in the outer peripheral portion of the rod 228 and a protrusion may be provided in the inner peripheral portion of the pusher body 224.

Next, an operation method (use method) of the medicine injection device 10E configured as described above will be described. The drug pusher 10E in which the first pusher 220 is inserted into the cylinder, the guide member 154 is connected to the outside of the cylinder, and the filling chamber is filled with the bone cement 80 is punctured into the bone 82 via the extension tube 92. And connected to the injection port 86 of the bone cement injection needle 84 (see FIG. 20A). The second pusher 222 is moved to the most distal side with respect to the first pusher 220.

When the handle 230 of the second pusher 222 is gripped and rotated while pressing the handle 230 toward the distal end with respect to the cylindrical body, the first pusher 220 and the second pusher 222 are not relatively rotatable. Therefore, the first pusher 220 and the second pusher 222 rotate together. At this time, a force is applied to the second pusher 222 to move the first pusher 220 in the proximal direction by the pressure from the bone cement 80 in the cylindrical body 150. Due to the pressing force in the distal direction with respect to 230, the second pusher 222 is prevented from moving in the proximal direction with respect to the first pusher 220. As a result, as shown in FIG. 20A, the first pusher 220 and the second pusher 222 move in the distal direction while integrally rotating with respect to the cylindrical body 150.

Then, as the first pusher 220 moves toward the distal end side with respect to the cylindrical body 12, the filling chamber 19 is pressurized to a high pressure, and the bone cement 80 moves the distal end pipe portion 20, the extension tube 92, and the bone cement injection needle 84. And injected into the bone 82. The movement of the first pusher 220 and the second pusher 222 toward the distal end side can be performed by a rotation operation with respect to the handle 230, so that the bone cement 80 can be injected with a relatively small operation force, and the first pusher. Since 220 has a relatively large diameter, a relatively large amount of bone cement 80 can be rapidly injected.

When the bone cement 80 is injected up to the target injection amount by rotating the handle 230, or when the injection of the bone cement 80 is suddenly stopped, the grip on the handle 230 is immediately released. That is, the hand is released from the handle 230. Then, since the action of preventing the movement of the second pusher 222 in the proximal direction by the gripping of the user is released, as shown in FIG. 20B, the second pusher 222 is caused by the pressure from the bone cement 80. The first pusher 220 moves in the proximal direction by an amount corresponding to the pressure remaining in the system. As a result, the pressure in the system is reliably released, so that the injection can be stopped reliably and a precise injection can be performed.

In the fifth embodiment, the components common to the first and third embodiments are the same or similar to the operations and effects provided by the common components in the first and third embodiments. Of course, the effect is obtained.

[Other Embodiments]
In the third to fifth embodiments described above, a cylinder 240 and a cylindrical cover 242 having the configuration shown in FIG. 21 may be employed instead of the cylinder 150 shown in FIG. The cylindrical body 240 has the male threaded portion 159 provided on the outer periphery of the base end portion in the cylindrical body 150 shown in FIG. 14 and the like, and is provided with a flange portion 244 that slightly expands radially outward. It corresponds to. The cylindrical cover 242 has a cylindrical shape with both ends opened, the cylindrical body 240 can be inserted, and has a length that can substantially cover the cylindrical body 240. The inner diameter of the inner peripheral portion of the cylindrical cover 242 is substantially the same as the outer diameter of the cylindrical body 240 at the proximal end portion of the cylindrical cover 242, but in the portion extending from the distal end portion to the vicinity of the proximal end portion, the cylindrical body 240. It is slightly larger than the outer diameter. Therefore, an annular clearance is formed between the inner peripheral surface of the cylindrical cover 242 and the outer peripheral surface of the cylindrical body 240 in a state where the cylindrical body 240 is inserted through the cylindrical cover 242.

A male screw portion 242 a that can be screwed into the first female screw portion 154 a of the guide member 154 is provided on the outer periphery of the base end portion of the cylindrical cover 242. In a state where the guide member 154 and the cylindrical body 240 are connected by screw fitting, the flange portion 244 of the cylindrical body 240 is sandwiched between the guide member 154 and the proximal end portion of the cylindrical cover 242. Thereby, the guide member 154 is fixed to the cylindrical body 240.

According to the cylindrical body 240 and the cylindrical cover 242 configured as described above, the cylindrical cover 242 functions as a heat transfer resistor even if the user grips the cylindrical cover 242 during a medicine injection operation. This makes it difficult for heat to be transmitted to the medicine in the cylindrical body 240, and the influence of heat being transmitted to the medicine can be reduced. In addition, the clearance 245 formed between the inner peripheral surface of the cylindrical cover 242 and the outer peripheral surface of the cylindrical body 240 functions as a heat insulating layer, thereby transferring heat from the user to the medicine in the cylindrical body 240. It can be effectively reduced.

[Bone cement filling method]
Next, a method for filling bone cement from the distal end of the cylindrical body 150 will be described using the pharmaceutical injection tool 10E according to the third embodiment as an example. As shown in FIG. 22A, the first pusher 152 in a state where the guide member 154 and the second pusher 156 are mounted is inserted into the cylindrical body 150 to the maximum. Next, the suction port 250 that functions as a nozzle is screwed into the distal end tube portion 160 of the cylindrical body 150 and attached. On the outer periphery of the proximal end of the suction port 250, a male screw portion 250a that can be screwed into a female screw portion 161 provided in the distal end pipe portion 160 is provided. Note that the suction port 250 may be attached to the distal end tube portion 160 before the first pusher 152 is inserted into the cylindrical body 150.

Next, as shown in FIG. 21B, the distal end portion of the suction port 250 is buried in the bone cement 80 prepared in the container 252, and in this state, the first pusher 152 is based on the cylindrical body 150. Pull in the end direction. Then, with the movement of the first pusher 152, the bone cement 80 is sucked into the cylindrical body 150 through the suction port 250. When a predetermined amount of bone cement 80 is sucked, the guide member 154 is rotated to move the first pusher 152 in the distal direction, and the guide member 154 and the proximal end portion of the cylindrical body 150 are connected and fixed. Thereby, the bone cement 80 is filled in the cylindrical body 150.

When the bone cement 80 is filled from the distal end of the cylindrical body 150 in this way, air does not enter the cylindrical body 150, so that the air discharging operation that occurs when the bone cement 80 is filled from the proximal end of the cylindrical body 150 is omitted. Can do.

In the above description, the present invention has been described with reference to preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

Claims

A drug injection device (10A, 10B, 10C, 10D, 10E) for discharging a drug filled inside,
A hollow cylinder (12, 102, 150, 240) having a medicine discharge port at the tip;
A first pusher (14, 104, 152, 200, 220) having a through-hole inserted in the hollow portion of the cylindrical body (12, 102, 150, 240) and penetrating in the axial direction;
As the first pusher (14, 104, 152, 200, 220) rotates with respect to the cylinder (12, 102, 150, 240), the first pusher (14, 104, 152, 200, 220). A feed screw structure (44, 144, 180) for axially displacing the cylinder (12, 102, 150, 240);
A second pusher (16, 106, 156, 202, 222) inserted in the through hole so as to be slidable in a liquid-tight manner in the axial direction.
A pharmaceutical injection device (10A, 10B, 10C, 10D, 10E).
The medicine injection device (10A, 10C, 10D, 10E) according to claim 1,
A guide member (40, 154) which is engageable with a base end portion of the cylindrical body (12, 150, 240) and has a female screw portion (42, 154b) formed therethrough;
On the outer peripheral portion of the first pusher (14, 152, 200, 220), male screw portions (38, 169) that are screwed into the female screw portions (42, 154b) are formed along the axial direction,
The feed screw structure (44, 180) includes the female screw portion (42, 154b) and the male screw portion (38, 169).
A drug injection device (10A, 10C, 10D, 10E).
The medicine injection device (10A, 10C, 10D, 10E) according to claim 2,
A first end of the first pusher (14, 152, 200, 220) or an outer periphery of the front end of the first pusher (14, 152, 200, 220) is slidable liquid-tightly along an inner peripheral surface of the cylindrical body (12, 150, 240). Sealing members (36, 166) are provided;
A drug injection device (10A, 10C, 10D, 10E).
The drug injection device (10A, 10B, 10C, 10D, 10E) according to claim 1,
First positioning means for regulating a position where the second pusher (16, 106, 156, 202, 222) is displaced to the most distal side with respect to the first pusher (14, 104, 152, 200, 220). (74, 138, 190, 211, 235),
Second positioning for restricting the position where the second pusher (16, 106, 156, 202, 222) is displaced most proximally with respect to the first pusher (14, 104, 152, 200, 220) Means (70, 136, 188),
A pharmaceutical injection device (10A, 10B, 10C, 10D, 10E).
The drug injection device (10A, 10B, 10C, 10D, 10E) according to claim 1,
A second seal member (60, slidable in a liquid-tight manner along the inner peripheral surface of the through hole is formed on the tip or the outer periphery of the tip of the second pusher (16, 106, 156, 202, 222). 121, 184) are provided,
A pharmaceutical injection device (10A, 10B, 10C, 10D, 10E).
In the medicine injection device (10A, 10B, 10C, 10D, 10E) according to claim 4,
Regardless of the position of the second pusher (16, 106, 156, 202, 222) within the movable range, the tip of the second pusher (16, 106, 156, 202, 222) Located in the through hole of the first pusher (14, 104, 152, 200, 220),
A pharmaceutical injection device (10A, 10B, 10C, 10D, 10E).
The medicine injection device (10A, 10B, 10C, 10D) according to claim 1,
Handles (54, 146, 170, 208) expanded outward are provided on the outer periphery of the base end of the first pusher (14, 104, 152, 200),
Flange portions (62, 130, 186, 214) that are expanded outward are provided on the outer periphery of the base end portion of the second pusher (16, 106, 156, 202).
A drug injection device (10A, 10B, 10C, 10D) characterized in that.
The drug injection device (10A, 10B, 10C, 10D, 10E) according to claim 1,
The drug is bone cement (80) injected into bone.
A pharmaceutical injection device (10A, 10B, 10C, 10D, 10E).
The pharmaceutical injection device (10A) according to claim 1,
The second pusher (16) is provided with an air discharge passage (126) for discharging air in the cylindrical body (12).
A drug injection device (10A) characterized by the above.
The medicine injection device (10C) according to claim 7,
The first pusher (152) includes a rod (168) inserted through the cylindrical body (150), and the handle (170) provided at a proximal end of the rod (168),
The handle (170) extends in the proximal direction so as to at least partially cover the second pusher (156) protruding from the proximal end of the rod (168).
A drug injection device (10C) characterized by the above.
The drug injection device (10C) according to claim 8,
The handle (170) is provided with a notch (172) that extends along the axial direction of the second pusher (156) and is open in the proximal direction of the handle (170).
A drug injection device (10C) characterized by the above.
The medicine injection device (10D) according to claim 7,
The handle (208) is provided with a recess (210) that opens in the proximal direction and into which the flange (214) of the second pusher (202) can be inserted.
A drug injection device (10D) characterized by the above.
The pharmaceutical injection device (10E) according to claim 1,
A handle (230) that expands outward is provided on the outer periphery of the base end of the second pusher (222),
The first pusher (220) and the second pusher (222) are fitted to each other such that they cannot rotate relative to each other.
A drug injection device (10E) characterized by the above.