WO2014132366A1

WO2014132366A1 - Spacer

Info

Publication number: WO2014132366A1
Application number: PCT/JP2013/055213
Authority: WO
Inventors: 中川雄司; 伊藤祐貴
Original assignee: テルモ株式会社
Priority date: 2013-02-27
Filing date: 2013-02-27
Publication date: 2014-09-04

Abstract

A spacer (10A) comprises: a balloon (18) capable of expanding consequent to the introduction of a filler; and an expansion restraining unit (20) which is disposed inside the balloon (18), which partially restrains the expansion of the balloon (18), and the restraint of which is released after the balloon (18) has been filled with a designated amount of the filler.

Description

Spacer

The present invention relates to a spacer that is placed between bones and expands the interval between the bones.

Lumbar spinal canal stenosis is a disease in which the spinal canal is constricted due to retrograde degeneration of the intervertebral disc or ligament, and causes symptoms such as low back pain, leg pain, and intermittent claudication. The mainstream of treatment for lumbar spinal canal stenosis is an operation that removes a part of the spine where the spinal canal is narrowed (laminectomy) or an operation that fixes the spine (spine fusion). On the other hand, as a relatively minimally invasive technique compared to laminectomy or spinal fusion, a metal spacer has recently been placed between the spinous processes to release the spinal nerve and nerve root compression. It has been developed. However, this method requires the incision of the back muscles and ligaments to place the spacer, so that the degree of invasiveness to the patient is still high, and hospitalization is also prolonged.

In response to such a problem, another method has been proposed in which a spacer implant is inserted between spinous processes and placed in a less invasive manner. As another method, for example, in US Patent Application Publication No. 2009/0118833, a puncture device that can puncture a living body and an expandable balloon are used, and the balloon is folded through an outer cylinder of the puncture device. A method is disclosed in which, after being inserted percutaneously between the spinous processes percutaneously in a state and filled with a filler such as bone cement in the balloon, the balloon is expanded and placed between the spinous processes. Since the filler is cured after filling the balloon, the balloon can be kept in a semi-permanent state.

When a spacer is placed between the spinous processes, the center of the spacer in the axial direction needs to be positioned at the center of the width direction of the interspinous ligament between adjacent spinous processes. However, when the spacer disposed between the spinous processes is filled with a filler, the spacer is displaced (slip) with respect to the spinous processes, and the center of the spacer in the axial direction is shifted from the center of the interspinous ligament in the width direction. May end up.

This is because either the spacer is folded asymmetrically in the axial direction, or the spacer hits the surrounding tissue (bone, muscle, ligament, etc.), so that either the leading or trailing end of the spacer expands first. It is generated by doing.

That is, for example, when the distal end side of the spacer is expanded first, the reaction force that pushes the spacer toward the distal end while the distal end side of the spacer contacts the spinous process in a state where the rear end side of the spacer is not in contact with the spinous process is generated. Since the projection acts on the spacer, the spacer is displaced relatively to the distal end side with respect to the spinous process.

Similarly, for example, when the rear end side of the spacer is expanded first, the rear end side of the spacer is in contact with the spinous process while the front end side of the spacer is not in contact with the spinous process, and the spacer is moved to the rear end side. Since the pushing reaction force acts on the spacer from the spinous process, the spacer is displaced relatively to the rear end side with respect to the spinous process.

Such misalignment becomes prominent when the spacer has large irregularities such as a so-called H-type or dumbbell-type. When the center in the axial direction of the spacer is greatly displaced from the center in the width direction of the interspinous ligament due to the positional shift, the spacer may be detached from between the spinous processes.

The present invention has been made in consideration of such problems, and an object of the present invention is to provide a spacer capable of preventing the occurrence of displacement of the spacer when the spacer is filled with a filler.

In order to achieve the above object, the present invention provides a spacer that is placed between bones and expands the space between the bones, the balloon being expandable with the introduction of a filler, and the inside of the balloon. And an expansion restricting portion that partially restricts the expansion of the balloon and releases the restriction after the balloon is filled with a predetermined amount of the filler.

According to the above configuration, when the filling material is introduced into the balloon, the restriction by the expansion restriction portion is released after the balloon is first expanded by filling the portion where the expansion restriction portion is not provided in the balloon. Then the balloon is secondary expanded. Therefore, it is possible to suppress the expansion of either the distal end side or the proximal end side of the balloon first by appropriately setting the region and order of expansion of the balloon. Therefore, it is possible to prevent the occurrence of displacement when the spacer is expanded.

In this case, a non-restricted portion that allows the filler to flow before the restriction by the expansion restricting portion is released may extend in the balloon in the longitudinal direction. According to this configuration, when the filler is introduced into the balloon, the non-restricted portion becomes the filler flow path, so that the balloon can be primarily expanded over a predetermined range in the longitudinal direction.

The expansion restricting portion may be provided at least on both sides of the center in the longitudinal direction of the balloon. According to this configuration, a portion of the balloon that contacts the bone from the lateral direction expands after other portions (both ends or the center in the longitudinal direction). For this reason, since the part expanded previously functions as a stopper, the position shift of a balloon can be prevented effectively.

The expansion restricting portion may be further provided at the center in the longitudinal direction of the balloon or at the distal end side and the proximal end side of the balloon. According to this configuration, since the center in the longitudinal direction of the balloon is secondarily expanded with a time delay, the displacement of the balloon can be more effectively prevented. Alternatively, by delaying secondary expansion on the distal end side and proximal end side of the balloon, it is possible to more effectively prevent the displacement of the balloon.

The balloon has a shape having a constricted portion and a bulging portion provided on both sides of the constricted portion at the time of expansion, and the expansion restricting portion is formed on at least a portion of the constricted portion on the constricted portion side. It may be provided. According to this configuration, a portion of the balloon that contacts the bone from the lateral direction expands after other portions (both ends or the center in the longitudinal direction). For this reason, since the part expanded previously functions as a stopper, the position shift of a balloon can be prevented effectively. Moreover, since the shape has the bulging portions on both sides of the constricted portion, the indwelling position of the spacer in the living body is stably maintained.

In this case, the expansion restricting portion may be further provided in a portion corresponding to the distal end portion and the proximal end portion of the balloon in the constricted portion or the bulging portion. According to this configuration, since the constricted portion of the balloon is secondarily expanded with a delay in time, the displacement of the balloon can be more effectively prevented. Alternatively, by delaying secondary expansion on the distal end side and proximal end side of the balloon, it is possible to more effectively prevent the displacement of the balloon.

A tube member disposed along the longitudinal direction of the balloon is provided in the balloon, and the distal end side and the proximal end side of the balloon communicate with each other through the tube member in the contracted state of the balloon. Also good. According to this configuration, since the passage of the filler is ensured by the tube member, the balloon can be surely primarily expanded over a predetermined range in the longitudinal direction as the filler is introduced into the balloon.

In the spacer, the balloon may be folded at a plurality of locations in the circumferential direction in the contracted state, and the expansion restricting portion may be provided on the inner surface of each folded portion of the balloon. According to this configuration, it is possible to effectively restrict the expansion of the balloon that has been folded into a contracted state.

In the spacer described above, the expansion restricting portion may be constituted by a fused portion or an adhesive portion. According to this configuration, the expansion restriction on the balloon is released when the fused portion or the contact portion is peeled off by the pressurization when the filler is introduced. Therefore, the primary expansion and the secondary expansion of the balloon can be surely performed with a simple configuration as the filler is introduced.

In the above spacer, the expansion restricting portion may exist in a grid shape or a dot shape. According to this configuration, the pressurizing force for secondary expansion can be easily set weak, and the injection pressure of the filler necessary for balloon expansion can be suppressed from becoming too high.

It is a partially-omission side view of the implant assembly provided with the spacer which concerns on 1st Embodiment of this invention. 2A is a schematic longitudinal sectional view of the spacer shown in FIG. 1, FIG. 2B is a transverse sectional view taken along line IIB-IIB in FIG. 2A, and FIG. 2C is a sectional view taken along line IIC-IIC in FIG. FIG. 3A is a first diagram illustrating a method for manufacturing a spacer, FIG. 3B is a second diagram illustrating a method for manufacturing the spacer, and FIG. 3C is a third diagram illustrating a method for manufacturing the spacer. FIG. FIG. 4A is a diagram illustrating another existence pattern of the expansion restriction unit, and FIG. 4B is a diagram illustrating still another existence pattern of the expansion restriction unit. FIG. 5A is an explanatory view of the insertion step in the method of inserting and placing a spacer between the spinous processes, and FIG. 5B is an explanatory view of the inserting step in the method of inserting and placing the spacer between the spinous processes. FIG. 6A is an explanatory diagram of the outer cylinder retracting step in the method of inserting and placing a spacer between the spinous processes, and FIG. 6B is a cross-sectional view taken along the line VIB-VIB in FIG. 6A. FIG. 7A is an explanatory diagram of a primary expansion step in the method of inserting and placing a spacer between the spinous processes, and FIG. 7B is an explanatory diagram of a secondary expansion step in the method of inserting and placing the spacer between the spinous processes. . FIG. 8A is an explanatory view showing a state in which the spacer is expanded at a desired position between the spinous processes, and FIG. 8B is an explanatory view of the detachment step in the method of inserting and placing the spacer between the spinous processes. It is a typical longitudinal section of the spacer concerning a 2nd embodiment of the present invention. 10A is a schematic longitudinal sectional view of a spacer according to a third embodiment of the present invention, FIG. 10B is a transverse sectional view taken along the line XB-XB in FIG. 10A, and FIG. 10C is a sectional view in FIG. FIG. 6 is a transverse sectional view taken along line XC-XC. 11A is a schematic longitudinal cross-sectional view of a spacer according to a fourth embodiment of the present invention, FIG. 11B is a cross-sectional view taken along line XIB-XIB in FIG. 11A, and FIG. 11C is in FIG. 11A. It is a cross-sectional view along the line XIC-XIC.

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

[First Embodiment]
FIG. 1 is a partially omitted side view of an implant assembly 12 including a spacer 10A according to a first embodiment of the present invention. The implant assembly 12 includes a spacer 10A provided at the distal end, and a catheter tube 14 (hereinafter referred to as “tube 14”) connected to the proximal end side of the spacer 10A.

The spacer 10A functions as an implant (spacer implant) to be inserted and placed in the living body, and is configured to be expandable by being filled with a filler 40 (see FIG. 7A). The part in the living body into which the spacer 10A is inserted is, for example, an interspinous process, a shoulder joint, or an intervertebral disc. The spacer 10A is contracted in the initial state as shown by the solid line in FIG. On the other hand, when the filler 40 is injected into the spacer 10A through the tube 14, the spacer 10A is expanded as shown by the phantom line in FIG.

The shape of the spacer 10 A at the time of expansion can be, for example, a shape in which a pair of bulging portions 16 are connected via a constricted portion 15 as shown in FIG. 1. When the shape of the spacer 10A at the time of expansion is such a dumbbell type, a wheel type (H type), or the like, the pair of bulging portions 16 disposed on both sides of the constricted portion 15 inserted through the interspinous ligaments are spinous processes. B1 is sandwiched (see FIG. 8B), which is preferable. The spacer 10A may have another shape such as a cylindrical shape.

FIG. 2A is a schematic longitudinal sectional view of the spacer 10A. As shown in FIG. 2A, the spacer 10 A includes a balloon 18 that can be expanded with the introduction of the filler 40, and an expansion restricting portion 20 provided in the balloon 18.

The balloon 18 constitutes a main body portion of the spacer 10A, and is formed in a bag shape. In the contracted state, the balloon 18 is folded in the circumferential direction to exhibit an elongated tubular shape. When the filler 40 is introduced into the balloon 18, the folded portion expands and expands to a preset shape and size as indicated by the phantom line in FIG.

The material of the balloon 18 may be a material that can be expanded by being injected with the filler 40 and can withstand external pressure associated with the movement of the vertebral body and tissues such as spinous processes and interspinous ligaments surrounding the balloon 18. For example, vinyl chloride, polyurethane elastomer, nylon, PET and the like can be mentioned without particular limitation.

The expansion restricting unit 20 is configured to partially restrict the expansion of the balloon 18 so that the restriction is released after the balloon 40 is filled with a predetermined amount of the filler 40. Accordingly, when the filler 40 is introduced into the balloon 18, the filler 18 is filled in a portion of the balloon 18 where the expansion restriction portion 20 is not provided, and the balloon 18 is first expanded (see FIG. 7A), and then expanded. The restriction by the restriction unit 20 is released, and the balloon 18 is secondarily expanded (see FIG. 7B).

As shown in FIG. 2A, in this embodiment, the expansion restricting portion 20 is provided in a portion corresponding to the constricted portion 15 and a portion corresponding to the constricted portion 15 side in the bulging portion 16. In FIG. 2A, the region where the expansion restricting portion 20 is provided is schematically shown by using cross hatching. However, in the balloon 18 in a contracted state, that is, a folded state, specifically, FIG. 2B and FIG. As described above, the expansion restricting portion 20 is provided.

2B and 2C are a cross-sectional view taken along line IIB-IIB in FIG. 2A and a cross-sectional view taken along line IIC-IIC in FIG. 2A, respectively. The balloon 18 is folded in the circumferential direction at a plurality of locations in the circumferential direction, and an expansion restriction portion 20 is provided on the inner surface of each folded portion. Thereby, the expansion restricting portions 20 are provided at a plurality of locations in the circumferential direction of the balloon 18. The expansion restricting portion 20 can be peeled off when a predetermined pressure or more is applied by introducing the filler 40 into the balloon 18.

Such an expansion restricting portion 20 can be constituted by, for example, a fused portion 21 or an adhesive portion 22. When the expansion restricting portion 20 is constituted by the fusion portion 21, the fusion portion 21 is a heat seal formed by heating and pressing the folded portion of the balloon 18 and fixing the inner surfaces of the portion. It is. The heat seal is made of a thermoplastic resin that functions as a seal that is weak enough to be peeled off when a predetermined pressure or more is applied by introducing the filler 40 into the balloon 18.

In this case, the balloon 18 itself may be made of a thermoplastic resin, and the fused portion 21 may be formed on the inner surface of the balloon 18 by heating and pressing the folded portion. Alternatively, a thermoplastic resin layer is separately provided on the inner surface of the balloon 18, and the fused portion 21 is formed by heating and pressing the folded portion of the balloon 18 to melt and solidify the thermoplastic resin layer. May be.

Examples of the thermoplastic resin include polyethylene, polypropylene, polyvinyl chloride, ethylene-vinyl acetate copolymer, polyamide, polyvinylidene chloride, polyvinyl fluoride, polytrifluoroethylene, polyethylene terephthalate, polyester, polyolefin resin, and the like. And mixtures thereof.

When the expansion restricting portion 20 is constituted by the bonding portion 22, the bonding portion 22 is an adhesive that is applied to the inner surface of the folded portion of the balloon 18 and hardened. The adhesive functions as a seal that is weak enough to be peeled off when a predetermined pressure or more is applied by introducing the filler 40 into the balloon 18.

As shown in FIGS. 2A to 2C, a non-restricting portion 24 that allows the filler 40 to flow inside the balloon 18 before the restriction by the expansion restriction portion 20 is released is inside the expansion restriction portion 20. The balloon 18 extends in the longitudinal direction (axial direction). This non-restricted portion 24 is a portion where the expansion restricting portion 20 is not provided, and becomes a flow path of the filler 40 when the filler 40 is introduced into the balloon 18.

A manufacturing method of such a spacer 10A will be described mainly with reference to FIGS. 3A to 3C, particularly when the expansion restricting portion 20 is the fusion portion 21.

First, a bag-like balloon 18 having a predetermined shape (for example, a shape indicated by a virtual line in FIG. 1) at the time of expansion is formed from a thermoplastic resin (see FIG. 3A). Next, a plurality of locations (4 locations in the illustrated example) in the circumferential direction of the obtained balloon 18 are folded so that the inner surfaces of each location are in contact with each other, and a portion 19 projecting radially at a plurality of locations in the circumferential direction in the cross section. (See FIG. 3B). In this case, the balloon 18 is folded so that some space remains in the central portion.

Then, the folded portions of the balloon 18 are sandwiched from the outside, heated, and pressed to form a fused portion 21 (heat seal) on the inner surface of each folded portion (see FIG. 3C). When the expansion restricting portion 20 is provided in the range shown in FIG. 2A, the range to be heated and pressed is only the constricted portion 15 of the balloon 18 and both side portions of the constricted portion 15.

After the fusion part 21 is formed, the radially projecting portion 19 of the balloon 18 is bent in the circumferential direction to be folded in the circumferential direction as shown in FIGS. 2B and 2C. Thereby, the spacer 10 A including the expansion restricting portion 20 configured by the fusion bonding portion 21 is obtained.

It should be noted that the expansion restricting portion 20 may exist in a grid shape as shown in FIG. 4A, or may exist in a dot shape as shown in FIG. 4B. 4A and 4B, the range in which the expansion restricting portion 20 is provided is the same as that of the expansion restricting portion 20 shown in FIG. 2A.

In FIG. 1, the tube 14 connected to the proximal end side of the balloon 18 is for sending (supplying) the filler 40 to the balloon 18. Specifically, the tube 14 is a long and thin member, and has a lumen 14 a that communicates with the inside (lumen) of the balloon 18 and functions as a flow path for the filler supplied to the balloon 18. The lumen 14 a communicates from the distal end to the proximal end of the tube 14.

The tube 14 has moderate flexibility so that it can be inserted into a curved puncture device 30 (see FIG. 5A) described later. Examples of the constituent material of the tube 14 include polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), polyvinyl chloride, and the like. , Polyamides, polyesters, polyester elastomers, polyamide elastomers, polyurethanes, polyurethane elastomers, polyimides, fluoropolymers, and mixtures thereof.

The spacer 10 A and the tube 14 are detachably connected via a connection structure 25. The connection structure 25 is, for example, a screwing structure, and when a predetermined torque or more is applied to the tube 14 and the spacer 10A, the screwing is released, so that the tube 14 and the spacer 10A are separated. Yes.

In addition to the above-described screwing structure, the connection structure 25 is a structure in which the members are separably connected by physical engagement (fitting, hooking, etc.), or any physical action (thermal action, chemical action, etc.). It is possible to adopt a structure that is separably connected by dividing by.

The base end of the tube 14 is provided with a hub 26 having a hollow structure that holds the base end. The hub 26 is made of, for example, a hard resin, has a lumen 26a communicating with the lumen 14a of the tube 14, and has a base end portion configured to be connectable to a filler supply source such as a syringe or a pump (not shown). ing.

The implant assembly 12 including the spacer 10A according to the present embodiment is basically configured as described above, and the operation and effect thereof will be described below.

Here, with reference to mainly FIGS. 5A to 8B, a procedure for inserting and placing the spacer 10A percutaneously between adjacent spinous processes in the living body using the puncture tool 30 will be described. 5A to 8B, the reference sign B is a vertebra, and the reference sign B1 is a spinous process formed in the rear part of the vertebra B.

5A, a puncture device 30 includes a hollow arc-shaped outer cylinder 32, a hub 34 fixed to the base end of the outer cylinder 32, an arc that can be inserted into the outer cylinder 32 and has the same curvature as the outer cylinder 32. It has an inner needle 36 formed in a shape, and a handle 38 fixed to the proximal end of the inner needle 36. FIG. 5A shows a state where the inner needle 36 is inserted into the hollow portion of the outer cylinder 32 as far as possible.

The outer cylinder 32 is a member having a hollow structure that is open at both ends and has a hollow portion into which the inner needle 36 can be inserted. The hub 34 fixed to the base end of the outer cylinder 32 has a larger outer diameter than the outer cylinder 32 and is provided in a flange shape.

The inner needle 36 is a rod-like member that is inserted into the hollow portion of the outer cylinder 32 and curved in an arc shape having a sharp needle tip 36a at the tip. When the inner needle 36 is inserted to the maximum with respect to the outer cylinder 32, the distal end of the inner needle 36 protrudes from the distal end of the outer cylinder 32 by a predetermined length. The inner needle 36 may be either a solid structure or a hollow structure. A handle 38 provided at the proximal end of the inner needle 36 functions as a grip for the user of the puncture device 30 to grasp.

A radiopaque marker may be provided on at least a part of the distal end side of the outer cylinder 32 or the inner needle 36 so as to be recognized under fluoroscopy.

The puncture device 30 used together with the implant assembly 12 is not limited to the puncture device 30 having the configuration shown in FIG. 5A, and for example, a straight type puncture device having a linear outer cylinder and an inner needle may be used. .

In the operation of placing the spacer 10A in the living body, first, after confirming the lesioned part with an X-ray fluoroscope, MRI, ultrasonic diagnostic apparatus, etc., the patient P is placed in the prone position. Next, as shown in FIG. 5A, the puncture device 30 with the inner needle 36 inserted into the outer tube 32 is inserted into the patient P to a predetermined depth under fluoroscopy (insertion step).

In the insertion step, more specifically, the interspinous ligament L between adjacent spinous processes is penetrated in the direction intersecting the axial direction of the spine with the outer cylinder 32 and the inner needle 36 of the puncture device 30. In this case, the distal end portion of the puncture device 30 is inserted to a position beyond a distance between the spinous processes by a predetermined length.

After the puncture device 30 has been inserted for a desired length, the inner needle 36 is then removed from the outer cylinder 32 while maintaining the position of the outer cylinder 32, that is, while the outer cylinder 32 is inserted into the patient P (inner needle). Extraction step). Thereby, the outer cylinder 32 is detained in a state where it is stuck in the living body.

Next, as shown in FIG. 5B, the implant assembly 12 having the contracted spacer 10A at the tip is inserted into the hollow portion of the outer cylinder 32 (insertion step). In this insertion step, specifically, as shown in FIG. 5B, the spacer 10A is located in the distal end portion of the outer cylinder 32, and the center of the spacer 10A in the axial direction is an interspinous ligament between adjacent spinous processes. The implant assembly 12 is inserted so as to be positioned at the center of L (see FIG. 6B). Thereby, the implant assembly 12 is inserted to a predetermined position in the outer cylinder 32.

Next, as shown in FIG. 6A, only the outer cylinder 32 (and the hub 34) is retracted in the proximal direction so that the entire length of the spacer 10A is exposed inside the body (outer cylinder retracting step). Here, FIG. 6B is a cross-sectional view taken along the line VIB-VIB in FIG. 6A. In FIG. 6B, the spacer 10 A penetrates the interspinous ligament L at a position corresponding to the constricted portion 15 of the balloon 18. Both end portions of the expansion restricting portion 20 provided in the balloon 18 are located outside the space between the spinous processes.

After the spacer 10A is arranged in such a state, next, a filler supply source (not shown) is connected to the hub 26 (see FIG. 1), and the filler supply source is operated to connect the balloon 18 via the tube 14 to the balloon 18. By injecting the filler 40, the spacer 10A is primarily expanded as shown in FIG. 7A (primary expansion step). Specifically, in this primary expansion step, when the filler 40 is introduced into the balloon 18 through the tube 14, the filler 40 is preferentially filled in the portion where the expansion restriction portion 20 is not provided. That is, the portion where the expansion restricting portion 20 is provided is not peeled until a predetermined pressure is applied, and the portion where the expansion restricting portion 20 is not provided is first to prevent the balloon 18 from being expanded (deployed). Expand.

In this case, in this embodiment, since the expansion restricting portion 20 is provided on the constricted portion 15 of the balloon 18 and its both side portions (portions on the constricted portion 15 side of the bulging portion 16), at the time of primary expansion, the bone (spinous process B1) ) Is restricted from extending laterally, and the reaction force that pushes the spacer 10A toward the distal end or the proximal end does not act on the spacer 10A from the spinous process B1. Therefore, the spacer 10A is not displaced during the primary expansion.

Next, by further injecting the filler 40 into the balloon 18, the expansion restriction by the expansion restriction unit 20 is released, and the balloon 18 is secondarily expanded (secondary expansion step). Specifically, after the primary expansion, when the filler 40 is further introduced into the balloon 18 and the pressure in the balloon 18 exceeds the pressure exceeding the restriction force of the expansion restriction part 20, the expansion restriction part 20 peels off, The expansion restriction of the balloon 18 by the expansion restriction unit 20 is released. When the expansion restriction by the expansion restriction unit 20 is released, the filler 40 flows into the portion where the expansion is restricted, and the balloon 18 is expanded to a predetermined size and shape as shown in FIG. 7B. At this time, since the portion that was previously expanded during the primary expansion functions as a stopper, the spacer 10A is not displaced during the secondary expansion.

The filler 40 is a material that is a fluid at the time of injection and hardens after injection (eg, bone cement, acrylic resin, two-component mixed cross-linked polymer, etc.), or a material that is a fluid at the time of injection and that maintains the fluid after the injection. Either can be applied. As shown in FIGS. 7B and 8A, the expanded spacer 10A (balloon 18) has a shape in which a pair of bulged portions 16 are connected via a constricted portion 15, and the constricted portion 15 has a spine between spinous processes. The interspinous ligament L is located between the pair of bulging portions 16 on both sides of the interstitial ligament L. Thereby, the space | interval between spinous processes is expanded by the expanded constriction part 15, and the spacer 10A will be in the state from which the removal from the interspinous ligament L between spinous processes was prevented.

After the spacer 10A is sufficiently expanded, the spacer 10A and the tube 14 are then separated (separation step) as shown in FIG. 8B. When the connection structure 25 between the spacer 10A and the tube 14 is a screwed structure, when the tube 14 is rotated around its axis, the spacer 10A inserted into the interspinous ligament L between adjacent spinous processes does not rotate, Only the tube 14 rotates, so that the spacer 10A and the tube 14 are unscrewed. Thereby, the spacer 10A and the tube 14 can be separated.

In addition, when the filler 40 is a material that is a fluid at the time of injection and is cured after the injection, the spacer 10A and the tube 14 are preferably separated after the filler 40 is cured. In addition, when the filler 40 is a material that maintains the fluid even after injection, a backflow prevention structure (check valve) may be provided at the inlet of the spacer 10A.

When the spacer 10A and the tube 14 are separated, the tube 14 is removed from the outer cylinder 32 and the outer cylinder 32 is completely removed from the patient P. As a result, the spacer 10A is placed between the spinous processes.

As described above, according to the spacer 10 A according to the present embodiment, when the filler 40 is introduced into the balloon 18, first, the filler 40 is placed in a location where the expansion restriction portion 20 is not provided in the balloon 18. The balloon 18 is firstly expanded by being filled, and then the restriction by the expansion restricting unit 20 is released and the balloon 18 is secondarily expanded. Therefore, by appropriately setting the part and order of expansion of the balloon 18, it is possible to suppress any one of the distal end side and the proximal end side of the balloon 18 from being expanded first. Therefore, it is possible to effectively prevent the positional deviation when the spacer 10A is expanded.

In this case, an unregulated portion 24 (see FIG. 2A) that allows the filler 40 to flow before the restriction by the expansion restricting portion 20 is released extends in the balloon 18 in the longitudinal direction of the balloon 18. According to this configuration, when the filler 40 is introduced into the balloon 18, the non-regulated portion 24 becomes a flow path for the filler 40, so that the balloon 18 is effectively primarily expanded over a predetermined range in the longitudinal direction. be able to.

Since the expansion restricting portion 20 is provided at least on both sides of the center of the balloon 18 in the longitudinal direction, the portion of the balloon 18 that contacts the bone from the lateral direction is behind the other portions (both ends or the center in the longitudinal direction). Expand. For this reason, since the part expanded previously functions as a stopper, the position shift of the balloon 18 can be prevented effectively.

In the case of this embodiment, since the expansion restricting portion 20 is also provided at the center in the longitudinal direction of the balloon 18, the center in the longitudinal direction of the balloon 18 is secondarily expanded with a time delay. Therefore, the position shift of the balloon 18 can be more effectively prevented.

According to this embodiment, in the deflated state, the balloon 18 is folded at a plurality of locations in the circumferential direction, and the fused portion 21 or the bonding portion 22 as the expansion restriction portion 20 is provided on the inner surface of each folded portion. . According to this configuration, the expansion restriction on the balloon 18 is released when the fused portion 21 or the adhesive portion 22 is peeled off by the pressure applied when the filler 40 is introduced. Accordingly, the primary expansion and the secondary expansion of the balloon 18 can be reliably performed with the introduction of the filler 40 with a simple configuration.

In this embodiment, since the expansion restricting portion 20 is provided on the inner surface of each folded portion of the balloon 18, the expansion of the balloon 18 configured to be folded and contracted can be effectively restricted.

If the expansion restricting portion 20 exists in a grid shape (see FIG. 4A) or a dot shape (see FIG. 4B), the pressure for secondary expansion can be set to be moderately weak, and the secondary of the balloon 18 can be set. It can suppress that the injection pressure of the filler 40 required for expansion becomes too high.

[Second Embodiment]
FIG. 9 is a schematic longitudinal sectional view of a spacer 10B according to the second embodiment of the present invention. The spacer 10B according to the second embodiment is different from the spacer 10A according to the first embodiment described above in that the tube member 42 is provided in the balloon 18, and other configurations are the same as those in the first embodiment.

Specifically, the tube member 42 is disposed on the inner side of the expansion restricting portion 20 along the longitudinal direction of the balloon 18 and has a lumen 42 a penetrating from one end 43 to the other end 44. One end 43 of the tube member 42 faces the space on the distal end side of the balloon 18, and the other end 44 of the tube member 42 faces the space on the proximal end side of the balloon 18. Therefore, the distal end side and the proximal end side of the balloon 18 communicate with each other through the tube member 42 in the contracted state of the balloon 18. Such a tube member 42 may be comprised by the 1 or more material selected from the material illustrated as a constituent material of the tube 14, for example.

According to the configuration of the present embodiment, since the passage of the filler 40 is secured by the tube member 42, when the filler 40 is introduced into the balloon 18, the filler 40 introduced to the proximal end side of the balloon 18 is used. The tube member 42 can be reliably introduced to the distal end side of the balloon 18. Therefore, the balloon 18 can be surely primarily expanded over the entire length in the longitudinal direction.

[Third Embodiment]
FIG. 10A is a schematic longitudinal sectional view of a spacer 10C according to the third embodiment of the present invention. 10B is a cross-sectional view taken along line XB-XB in FIG. 10A, and FIG. 10C is a cross-sectional view taken along line XC-XC in FIG. 10A. Note that in the third embodiment, components that are the same as or similar to those in the first embodiment are given the same reference numerals, and detailed descriptions thereof are omitted.

The spacer 10C according to the third embodiment is different from the spacer 10A according to the first embodiment in that the expansion restricting portion 20 is provided at a location corresponding to the bulging portion 16 of the balloon 18. Specifically, in the spacer 10 C, the expansion restricting portion 20 does not exist in the portion corresponding to the constricted portion 15, and the portions corresponding to the two bulging portions 16 (from both sides of the constricted portion 15 to the distal end side of the balloon 18. And the range up to the base end side) is present in the expansion restricting portion 20.

As shown in FIGS. 10A and 10B, the expansion restricting portions 20 are provided at a plurality of locations in the circumferential direction. Inside the deflated balloon 18, an unregulated portion 24 (space) that allows the filler 40 to flow before the restriction by the expansion restricting portion 20 is released in the longitudinal direction of the balloon 18. Extend.

When the filler 40 is introduced through the tube 14 into the spacer 10C configured as described above, first, the filler 40 is preferentially filled in a portion where the expansion restriction portion 20 is not provided. That is, the portion where the expansion restricting portion 20 is provided is not peeled until a predetermined pressure is applied, and the portion where the expansion restricting portion 20 is not provided is first to prevent the balloon 18 from being expanded (deployed). Expand.

In this case, in this embodiment, since the expansion restricting portion 20 is provided at a location corresponding to the bulging portion 16 of the balloon 18, the portion that can come into contact with the bone (spinous process B1) from the lateral direction is expanded during the primary expansion. The reaction force that is regulated and pushes the spacer 10C toward the distal end side or the proximal end side does not act on the spacer 10C from the spinous process B1. Therefore, the positional displacement of the spacer 10C does not occur during the primary expansion.

Further, after the primary expansion, when the filler 40 is further introduced into the balloon 18 and the pressure in the balloon 18 exceeds the pressure exceeding the restriction force of the expansion restriction part 20, the expansion restriction part 20 peels off, and the expansion restriction part The expansion restriction of the balloon 18 by 20 is released. When the expansion restriction by the expansion restriction unit 20 is released, the filler 40 flows into the portion where the expansion is restricted, so that the balloon 18 is expanded to a predetermined size and shape (secondary expansion). At this time, since the portion that was previously expanded during the primary expansion functions as a stopper, the spacer 10C is not displaced during the secondary expansion.

In the spacer 10C, the expansion restricting portion 20 may exist in a grid shape or a dot shape, similarly to the configuration of FIG. 4A or 4B.

In the third embodiment, it is needless to say that the same or similar operational effects as those in the first embodiment can be obtained for the same or similar components as those in the first embodiment.

[Fourth Embodiment]
FIG. 11A is a schematic longitudinal sectional view of a spacer 10D according to the fourth embodiment of the present invention. 11B is a cross-sectional view taken along line XIB-XIB in FIG. 11A, and FIG. 11C is a cross-sectional view taken along line XIC-XIC in FIG. 11A. Note that in the fourth embodiment, identical or similar components to those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted.

The spacer 10D according to the fourth embodiment is different from the spacer 10A according to the first embodiment in that the expansion restricting portion 20 is provided at a location corresponding to the constricted portion 15 and the bulging portion 16 of the balloon 18. Specifically, the expansion restricting portion 20 in the spacer 10 D is provided from the distal end side to the proximal end side of the balloon 18. As shown in FIGS. 11A to 11C, the expansion restricting portions 20 are provided at a plurality of locations in the circumferential direction. Inside the deflated balloon 18, an unregulated portion 24 (space) that allows the filler 40 to flow before the restriction by the expansion restricting portion 20 is released in the longitudinal direction of the balloon 18. Extend.

When the filler 40 is introduced into the spacer 10 D configured as described above via the tube 14, first, the filler 40 is preferentially filled in a portion where the expansion restriction unit 20 is not provided (primary expansion). ). That is, the portion where the expansion restricting portion 20 is provided is not peeled until a predetermined pressure is applied, and the portion where the expansion restricting portion 20 is not provided is first to prevent the balloon 18 from being expanded (deployed). Expand.

In this case, in this embodiment, since the expansion restricting portion 20 is provided from the distal end side to the proximal end side of the balloon 18, expansion of a portion that can contact the bone (spinous process B1) from the lateral direction is restricted during primary expansion. The reaction force that pushes the spacer 10D toward the distal end side or the proximal end side does not act on the spacer 10D from the spinous process B1. Accordingly, the spacer 10D is not displaced during the primary expansion.

Further, after the primary expansion, when the filler 40 is further introduced into the balloon 18 and the pressure in the balloon 18 exceeds the pressure exceeding the restriction force of the expansion restriction part 20, the expansion restriction part 20 peels off, and the expansion restriction part The expansion restriction of the balloon 18 by 20 is released. When the expansion restriction by the expansion restriction unit 20 is released, the filler 40 flows into the portion where the expansion is restricted, so that the balloon 18 is expanded to a predetermined size and shape (secondary expansion). At this time, since the portion that was previously expanded during the primary expansion functions as a stopper, the spacer 10D is not displaced during the secondary expansion.

In the spacer 10D, the expansion restricting portion 20 may exist in a grid shape or a dot shape, similarly to the configuration of FIG. 4A or FIG. 4B.

In the fourth embodiment, the same or similar functions and effects as those of the first embodiment can be obtained for the same or similar components as those of the first embodiment.

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. Yes.

Claims

Spacers (10A, 10B, 10C, 10D) that are placed between the bones and extend the spacing between the bones,
A balloon (18) that is expandable with the introduction of the filler (40);
An expansion provided in the balloon (18), which partially restricts the expansion of the balloon (18) and releases the restriction after the balloon (18) is filled with a predetermined amount of the filler (40). A regulation unit (20),
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to claim 1,
In the balloon (18), a non-restricted portion (24) that allows the filler (40) to flow before the restriction by the expansion restricting portion (20) is released is the length of the balloon (18). Extending in the direction,
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to claim 2,
The expansion restricting portion (20) is provided at least on both sides of the center in the longitudinal direction of the balloon (18).
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to claim 3,
The expansion restricting portion (20) is further provided at the center in the longitudinal direction of the balloon (18) or at the distal end side and the proximal end side of the balloon (18).
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to claim 2,
The balloon (18) has a shape having a constricted portion (15) and a bulging portion (16) provided on both sides of the constricted portion (15) when expanded.
The expansion restricting portion (20) is provided at least on the constricted portion (15) side portion of the bulging portion (16).
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to claim 5,
The expansion restricting portion (20) is further provided in a portion corresponding to the distal end side and the proximal end side of the balloon (18) in the constricted portion (15) or the bulging portion (16).
A spacer (10A, 10B, 10C, 10D) characterized by that.
Spacer (10B) according to claim 2,
In the balloon (18), a tube member (42) arranged along the longitudinal direction of the balloon (18) is provided,
In the contracted state of the balloon (18), the distal end side and the proximal end side of the balloon (18) communicate with each other through the tube member (42).
The spacer (10B) characterized by this.
The spacer (10A, 10B, 10C, 10D) according to any one of claims 1 to 7,
The balloon (18) is folded at a plurality of locations in the circumferential direction in the contracted state,
The expansion restricting portion (20) is provided on the inner surface of each folded portion of the balloon (18).
A spacer (10A, 10B, 10C, 10D) characterized by that.
Spacer (10A, 10B, 10C, 10D) according to claim 8,
The expansion restriction part (20) is constituted by a fusion part (21) or an adhesive part (22).
A spacer (10A, 10B, 10C, 10D) characterized by that.
The spacer (10A, 10B, 10C, 10D) according to any one of claims 1 to 7,
The expansion restricting portion (20) exists in a grid shape or a dot shape,
A spacer (10A, 10B, 10C, 10D) characterized by that.