CN111053606B

CN111053606B - Integrated injection method and device for injectable bone substitute in vertebral body shaping

Info

Publication number: CN111053606B
Application number: CN201911311859.3A
Authority: CN
Inventors: 陈博; 李朝阳; 吕维加
Original assignee: Shandong Mantak Biomedical Engineering Co ltd
Current assignee: Shandong Mantak Biomedical Engineering Co ltd
Priority date: 2019-12-18
Filing date: 2019-12-18
Publication date: 2025-06-24
Anticipated expiration: 2039-12-18
Also published as: CN111053606A

Abstract

An integrated injection implementation method and device for injectable bone substitutes in vertebral body shaping belongs to the field of medical devices. A memory alloy guide needle is inserted into a hollow tube for thermal pre-forming, and the two are pushed into the vertebral body in an integrated manner. Under the guidance of the memory alloy guide needle, the hollow tube quickly rebounds to its original curvature through internal stress, forming the boundary of the injectable bone substitute filling space or serving as a boundary fence of the filling space; the injectable bone substitute is injected into the designated position through the hollow tube; at the designated position in the vertebral body, the injectable bone substitute fills the hollow tube and the filling space surrounded by it. It makes the injection area of the injectable bone substitute plannable, and integrates the puncture, distraction, injection of implants and bone cement, and molding in vertebroplasty; all steps are carried out simultaneously, which greatly optimizes the operation process, shortens the operation time, and reduces the difficulty of operation. It can be widely used in the design and manufacturing of orthopedic implant injection devices.

Description

Integrated injection implementation method and device for injectable bone substitute in vertebral body molding

Technical Field

The present invention is in the field of surgical instruments, devices or methods, and more particularly, to a method and device for injecting and shaping bone substitutes into vertebral bodies.

Background

Percutaneous vertebroplasty (percutaneous vertebroplasty, PVP) and percutaneous kyphoplasty (percutaneous kyphoplasty, PKP) have been used clinically for many years, with the major clinical problems:

1) Uncertainty of bone cement injection area.

In the traditional balloon operation, injected bone cement has no boundary constraint, is free to disperse and fill, and has poor controllability. Therefore, the injection quantity is difficult to accurately calculate before operation, the molding effect is difficult to achieve due to the too small injection quantity, and the side leakage risk is caused due to the too large injection quantity.

2) High probability complications caused by bone cement leakage.

When the cortical bone of the outer layer of the vertebral body is slightly damaged, the leakage effect is unavoidable, once the leakage occurs to the vertebral canal and the intervertebral foramen area, the leakage can cause nerve symptoms with high probability, and the leakage into the vein can form pulmonary embolism to endanger life;

3) The mechanical bearing effect is poor.

The maximum load cannot be formed in the vertical direction because the injected bone cement is dispersed without a fixed space structure. Due to the improper spatial distribution of the bone cement, the bone cement is stressed unevenly and is easy to break, so that the vertebral body is secondarily collapsed, and the repair operation is required.

4) The vertebral body expansion and bone cement injection in the traditional PKP are required to be carried out step by step, the steps are complicated, most of operations such as expansion degree, bone cement injection quantity, injection rate and the like are required to be judged according to the experience of an operator, the fault tolerance is low, the repeatability is poor, and the requirement on operation skills is extremely high.

How to plan and define the injection molding area of bone cement before operation, reduce or avoid the leakage of bone cement, and integrally combine the centrum expansion and the bone cement injection, reduce the requirement or dependence on the operation skill of operators, so that the injected bone cement can have better mechanical bearing effect, and is a technical problem which is attempted to be solved in actual work.

Disclosure of Invention

The invention aims to solve the technical problem of providing an integrated injection implementation method and device for an injectable bone substitute in vertebral body molding, which are characterized in that a linear memory alloy guide needle is inserted into a biocompatible polymer hollow tube, thermal pre-shaping is carried out, the two hollow tubes are synchronously pushed into a vertebral body in an integrated way, under the guidance of the memory alloy guide needle, the biocompatible polymer hollow tube rapidly rebounds to the original curvature through internal stress, so that the boundary of an injectable bone substitute filling space or a boundary fence serving as the filling space is formed, then the injectable bone substitute is injected into a designated position through the hollow tube, and the biocompatible polymer hollow tube and the filling space enclosed by the biocompatible polymer hollow tube are filled with the injectable bone substitute at the designated position in the vertebral body. The injection method ensures that the injection area of the injectable bone substitute has plandability, integrates the multi-step operations of puncturing, expanding, injecting the endophyte, bone cement, forming and the like in vertebroplasty, synchronously carries out all the steps, greatly optimizes the operation flow, shortens the operation time and reduces the operation difficulty.

The technical scheme of the invention is to provide an integrated injection implementation method of an injectable bone substitute in the process of vertebral body molding, which is characterized in that:

1) Pre-bending the biocompatible polymer hollow tube and sealing the front end of the tube;

2) Inserting a linear memory alloy guide pin into the biocompatible polymer hollow tube, and forming a 'needle core' of the biocompatible polymer hollow tube by the memory alloy guide pin, so that the two hollow tubes form an integrated structure;

3) Performing thermal pre-shaping on the biocompatible polymer hollow tube inserted with the needle core to form a required pre-shaped structure shape;

4) A pushing driving device at least comprising a section of puncture sleeve with a straight pipe section structure is adopted to force the biocompatible polymer hollow pipe with a preset structure shape and the memory alloy guide pin to synchronously push the biocompatible polymer hollow pipe into the vertebral body in a linear structure shape;

5) The biocompatible polymer hollow tube separated from the straight tube-shaped puncture sleeve is quickly rebounded to the original curvature through the internal stress under the guidance of the memory alloy guide pin at the appointed position in the vertebral body, and keeps consistent with the shape of the preset structure;

6) Continuously and synchronously pushing the biocompatible polymer hollow tube and the memory alloy guide pin;

7) Under the guidance of the memory alloy guide pin, the biocompatible polymer hollow tube continuously forms a preset structural shape at a designated part in the vertebral body until the shape or the height completely meets the requirement, and the vertebral body is spread to a required interval;

8) Drawing out the memory alloy needle in the biocompatible polymer hollow tube;

9) Injecting an injectable bone substitute into the biocompatible polymeric hollow tube;

10 Through guidance and restriction of the biocompatible polymeric hollow tube, the injectable bone substitute is continuously injected to the designated site within the vertebral body;

11 At the designated part of the vertebral body, the injectable bone substitute is filled with the biocompatible polymer hollow tube or the injectable bone substitute is filled with the biocompatible polymer hollow tube and a filling space enclosed by the biocompatible polymer hollow tube;

12 Cut off the hollow tube of biocompatible macromolecule beyond the external part of the centrum or the needed length;

13 The injectable bone substitute forms a three-dimensional filling body at a designated part in the vertebral body;

14 After the solid filling injectable bone substitute is solidified, a bone substitute which can bear pressure and has the same or similar strength with the vertebral body at the position is formed;

According to the integrated injection implementation method, the biocompatible polymer hollow tube serving as a needle core is pushed/injected to the designated part in the vertebral body by the memory alloy guide needle to form the boundary of the filling space or serve as the boundary fence of the filling space, so that the molding plandability and controllability of the injectable bone substitute are realized, the leakage risk of the injectable bone substitute is avoided, and then the multi-step operations of puncturing, expanding, injecting the inner plant, molding and solidifying the injectable bone substitute in vertebroplasty are integrally realized, so that the operation flow is optimized, the operation time is shortened, and the operation difficulty is reduced.

In particular, the injectable bone substitute comprises at least injectable bone cement, CPC or gel.

The injection area of the injectable bone substitute at least comprises the planability, the implantation position of the injectable bone substitute is controllable, the injection amount of the injectable bone substitute is controllable, the spreading/forming effect of the injectable bone substitute is controllable and the mechanical support of the injectable bone substitute is controllable.

The predetermined structural shape includes at least a helical coil structure.

Further, the pre-bending pretreatment of the biocompatible polymer hollow tube comprises processing/arranging annular, snake-shaped or spiral cutting grooves on the outer surface of the biocompatible polymer hollow tube to facilitate the thermal pre-shaping and the recovery of the predetermined structural shape of the biocompatible polymer hollow tube.

The technical scheme of the invention is that the integrated injection device for injecting bone substitute in the process of vertebral body molding is characterized in that:

The integrated injection device at least comprises a pushing driving device, a biocompatible polymer hollow tube and a linear memory alloy guide pin;

The pushing driving device is provided with a section of straight tubular puncture sleeve;

the memory alloy guide pin penetrates through the biocompatible polymer hollow tube;

the front end of the biocompatible polymer hollow tube is closed;

The pushing driving device is used for pushing the biocompatible polymer hollow tube and the memory alloy guide pin to a designated position in the vertebral body;

The memory alloy guide pin is used for guiding the bending and forming of the biocompatible polymer hollow tube, discharging most of air in the hollow tube, preventing the extrusion of the injection channel when the biocompatible polymer hollow tube is bent, and keeping a good injectable bone substitute injection channel;

the biocompatible polymer hollow tube forms a filling channel for the injectable bone substitute and a boundary or boundary fence for the filling space of the injectable bone substitute.

The method comprises the steps of carrying out thermal presetting on a biocompatible polymer hollow tube and a memory alloy guide needle, carrying out thermal presetting on the biocompatible polymer hollow tube and the memory alloy guide needle, carrying out prefabricated forming, then placing the prefabricated biocompatible polymer hollow tube and the memory alloy guide needle into a pushing driving device, inserting a puncture sleeve of the pushing driving device into a required designated position in a vertebral body, continuously and synchronously integrally sending out the prefabricated biocompatible polymer hollow tube and the memory alloy guide needle by means of the puncture sleeve, carrying out forced restraint and guidance of a straight tubular puncture sleeve, carrying out straight tubular/linear conveying on the prefabricated biocompatible polymer hollow tube and the memory alloy guide needle to a designated position in the vertebral body, and rapidly rebounding the biocompatible polymer hollow tube leaving the straight tubular puncture sleeve to an original curvature by means of the internal stress under the guidance of the memory alloy guide needle, so as to restore/keep consistent with the shape after thermal presetting.

The integrated injection device continuously and synchronously pushes the biocompatible polymer hollow tube and the memory alloy guide pin in an integrated manner, so that an injectable bone substitute filling space which is the same as or similar to the shape of the biocompatible polymer hollow tube after heat presetting is formed in the vertebral body.

Further, a plurality of side holes are arranged on one side of the biocompatible polymer hollow tube, after the biocompatible polymer hollow tube is thermally pre-molded, the side holes face the inside of a filling space surrounded by the biocompatible polymer hollow tube, the biocompatible polymer hollow tube is filled with the injectable bone substitute by pushing/injecting, or the biocompatible polymer hollow tube with a plurality of side hole structures is filled with the injectable bone substitute by pushing/injecting, and the three-dimensional filling space surrounded by the biocompatible polymer hollow tube.

The technical scheme of the invention also provides an integrated injection device for injecting bone substitute in the process of vertebral body molding, which is characterized in that:

The integrated injection device comprises a pushing driving device, a flexible shaft tube, a head drill bit and a linear memory alloy guide pin, wherein the head drill bit is arranged at the head end of the flexible shaft tube, the tail end of the flexible shaft tube is connected with the pushing driving device, the linear memory alloy guide pin penetrates through the flexible shaft tube, the pushing driving device is provided with a section of straight tubular puncture sleeve, and the memory alloy guide pin is used for guiding the flexible shaft tube to bend and form.

The pushing driving device drives the head drill bit to rotate through the flexible shaft tube, pushes the flexible shaft tube, the head drill bit and the memory alloy guide pin to a designated position in the vertebral body along a path guided by the memory alloy guide pin, and simultaneously continuously and synchronously integrally sends out the flexible shaft tube, the memory alloy guide pin and the head drill bit by means of the puncture sleeve.

The flexible shaft tube forms a boundary or boundary fence of the injection channel of the injectable bone substitute and the filling space of the injectable bone substitute.

The integrated injection device is used for continuously tunneling a spiral bone tunnel for accommodating the flexible soft shaft tube in the vertebral body through a shield tunneling mode.

The memory alloy guide needle is inserted into the flexible shaft tube, after being subjected to heat presetting, the memory alloy guide needle is placed into the pushing driving device, the puncture sleeve of the pushing driving device is inserted into a required designated position in the vertebral body, and the pushing driving device continuously and synchronously integrally sends out the flexible shaft tube after heat presetting and the memory alloy guide needle by means of the puncture sleeve.

Under the forced constraint and guide of the straight pipe-shaped puncture sleeve, the heat-preformed flexible shaft pipe and the memory alloy guide pin are conveyed to a designated position in the cone in a straight pipe/straight line mode, the pushing driving device drives the head drill bit to rotate through the flexible shaft pipe to form a shield tunneling mode, and the flexible shaft pipe which leaves the straight pipe-shaped puncture sleeve is quickly rebounded to the original curvature through the internal stress under the guide of the memory alloy guide pin and is consistent with the shape recovery/maintenance after heat reservation.

The head drill bit is guided by the memory alloy guide pin to form a spiral bone tunnel in the vertebral body, and the flexible shaft tube is guided by the memory alloy guide pin to form an injectable bone substitute filling space in the vertebral body, wherein the injectable bone substitute filling space is the same as or similar to the shape of the memory alloy guide pin after heat presetting.

The flexible shaft tube comprises a four-layer structure, wherein the outer layer of the flexible shaft tube is a degradable polymer tube, the flexible shaft tube is reserved in a vertebral body after bone tunneling is completed, then an injectable bone substitute is injected into the flexible shaft tube, the outer diameter of the wear-resistant tube is equal to the inner diameter of the outer layer tube, the wear-resistant tube, an inner layer driving shaft, a memory alloy guide pin and a puncture sleeve are pulled out together after bone tunneling is completed, the inner layer of the flexible shaft tube is a flexible rotating shaft for driving a drill bit to rotate, the diameter of the flexible rotating shaft is half of that of the wear-resistant tube, a hollow pipeline is formed between the flexible rotating shaft and the inner layer driving shaft, the memory alloy guide pin and the puncture sleeve and is pulled out together after bone tunneling is completed, the flexible rotating shaft tube is a hollow shaft core layer inside the flexible driving shaft, and the shaft core layer is a hollow structure inside the flexible driving shaft and can freely pass through the memory alloy guide pin.

Wherein the space between the outer layer and the middle layer forms an annular tubular structure for providing a discharge passage for bone chips drilled by the drill bit.

Furthermore, the shape of the memory alloy guide pin after heat presetting at least comprises a spiral shape structure, and annular, snake-shaped or spiral grooves are arranged on the outer surface of the biocompatible polymer hollow tube or the flexible soft shaft tube.

Compared with the prior art, the invention has the advantages that:

1. The injection device/endophyte (namely the biocompatible polymer hollow tube or the flexible shaft tube) is used for forming a certain injection bone substitute filling space inside the vertebral body, so that an injection area of the injection bone substitute has planning property, and the injection quantity of bone cement can be calculated through a pre-operation established space structure;

2. the bearing mechanical effect can be accurately obtained through the space structure and the dosage of the injectable bone substitute, and the consistency of the internal and external mechanical properties of the implanted object is ensured;

3. The rail structure formed by the injectable apparatus/endophyte avoids and eliminates the leakage risk of injectable bone substitute and avoids various complications caused by the leakage risk;

4. The operation steps are simplified by the puncture, the tunneling molding of the bone tunnel and the injection of the injectable bone substitute, and the vertebroplasty is improved from the empirical operation to the level of digitalization, mechanization and standard quantification.

Drawings

FIG. 1 is a schematic flow diagram of the method of the present invention;

FIG. 2 is a schematic structural view of a hollow tube of biocompatible polymer according to the present invention;

FIG. 3 is a schematic diagram of the structure of a biocompatible polymer hollow tube with a groove on the periphery;

FIG. 4 is a schematic structural view of a helical biocompatible polymer hollow tube;

FIG. 5 is a schematic structural view of a helical biocompatible polymeric hollow tube with grooves;

FIG. 6 is a schematic diagram of the construction of a push drive;

FIG. 7 is a schematic illustration of the operation of the push drive;

FIG. 8 is a schematic diagram of the simultaneous penetration of a biocompatible polymer hollow tube and a memory alloy introducer needle in accordance with the present invention;

FIG. 9 is a schematic view showing the memory alloy needle beginning to bend into a spiral shape;

FIG. 10 is a schematic illustration of the biocompatible polymer hollow tube after complete bending;

FIG. 11 is a schematic view of the structural shape of a memory alloy needle in a filling space;

FIG. 12 is a schematic drawing of the draw-out memory alloy needle;

FIG. 13 is a schematic view of the beginning of injection of bone cement;

FIG. 14 is a schematic illustration of bone cement not yet overflowing from the side hole after filling the biocompatible polymeric hollow tube entirely;

FIG. 15 is a schematic view of bone cement after filling the biocompatible polymeric hollow tube entirely and overflowing the side hole;

FIG. 16 is a schematic view of the construction of a shield bit and its flexible shaft;

FIG. 17 is a schematic view of the structure of the flexible shaft tube;

FIG. 18 is a schematic cross-sectional view of a flexible shaft tube;

FIG. 19 is a partially enlarged schematic view of the portion A of FIG. 18;

FIG. 20 is a schematic illustration of a biocompatible polymer hollow tube piercing to the point of origin of injection;

FIG. 21 is a schematic view of the drill reaching the pedicle start point;

FIG. 22 is a schematic view of a guide wire guiding a flexible drill bit to simultaneously tunnel bone;

FIG. 23 is a schematic illustration of the completion of bone tunneling;

fig. 24 is a schematic illustration of the bone cement filling.

In the figure, 0 is a cone, 1 is a biocompatible polymer hollow tube, 1A is a spiral tube, 2 is a closed end, 3 is an inner hole, 4 is a cutting groove, 5 is a memory alloy guide pin, 6 is a puncture sleeve, 6A is a puncture needle, 7 is a pushing driving device, 8 is an injectable bone substitute, 9 is a bone substitute, 10 is a driving handle, 11 is a driving shaft, 12 is a belt, 13A is an active roller, 13B is a passive roller, 14 is an injectable spiral tube bin, 20 is a head drill, 21 is a degradable tube, 22 is a wear-resistant tube, 23 is a flexible rotating shaft, 24 is a hollow shaft center layer, and 25 is an annular tube.

Detailed Description

The invention is further described below with reference to the drawings and examples.

In fig. 1, the technical scheme of the present invention provides an integrated injection implementation method of an injectable bone substitute in vertebral body molding, which is characterized in that:

pre-bending a biocompatible polymer hollow tube (hollow tube or pipe for short) 1, and sealing the front end of the hollow tube to form a closed end 2;

a linear memory alloy guide pin 5 is inserted into a biocompatible polymer hollow tube, and the memory alloy guide pin forms a 'needle core' of the hollow tube, so that the hollow tube and the memory alloy guide pin form an integrated structure;

performing thermal pre-shaping on the biocompatible polymer hollow tube inserted with the needle core to form a required pre-shaped structure shape;

A pushing driving device of a puncture sleeve 6 at least comprising a section of straight tube-shaped structure is adopted, a biocompatible polymer hollow tube with a preset structure shape and a memory alloy guide needle are forced to synchronously push into a vertebral body in a linear structure shape under the action of the puncture sleeve;

The biocompatible polymer hollow tube separated from the straight tube-shaped puncture sleeve is quickly rebounded to the original curvature through the internal stress under the guidance of the memory alloy guide pin at the appointed position in the vertebral body, and keeps consistent with the shape of the preset structure;

Continuously and synchronously pushing the biocompatible polymer hollow tube and the memory alloy guide pin;

under the guidance of the memory alloy guide pin, the biocompatible polymer hollow tube continues to bend at the appointed position in the vertebral body to form a preset structural shape until the biocompatible polymer hollow tube completely meets the required shape or height, and the vertebral body is propped up to the required interval;

Drawing out the memory alloy needle in the biocompatible polymer hollow tube;

injecting the injectable bone substitute 8 into a biocompatible polymeric hollow tube;

The injectable bone substitute is continuously injected to a designated part in the vertebral body through the guidance and limitation of the biocompatible polymer hollow tube;

At the appointed position in the vertebral body, the injectable bone substitute is filled with the biocompatible polymer hollow tube, or the injectable bone substitute is filled with the biocompatible polymer hollow tube and a filling space enclosed by the biocompatible polymer hollow tube;

The injectable bone substitute forms a three-dimensional filling body at a designated part in the vertebral body;

After the solid filling injectable bone substitute is solidified, a bone substitute which can bear pressure and has the same or similar strength with the vertebral body at the position is formed;

It is stated that the technical scheme related by the invention belongs to orthopaedics implants and corresponding matched tools, and more particularly relates to a molding method and a device of an injectable bone substitute (also called injectable bone cement for short) and does not belong to a disease diagnosis and treatment method.

The material of the biocompatible polymer hollow tube in the technical scheme of the invention can be one of PEEK (poly-ether-ketone, polyether-ether-ketone resin), PLGA (poly (lactic-co-glycolic acid, glycolic acid-lactic acid copolymer), PCL (Polycaprolactone ), PGA (Polyglycolic acid, polyglycolic acid) or PLA (polylactic acid).

The predetermined structural shape in the technical scheme of the invention at least comprises a spiral coil structure.

In addition, although described as an injectable bone substitute, the technical solution of the present patent is applicable to the method, including but not limited to injectable bone cement, CPC (Calcium Phosphate Cement, calcium phosphate bone cement), gel, etc., and is applicable not only to the bone substitute commonly used at the present stage, but also to injectable bone materials with better future performances along with the advancement of materialization.

Although the spiral forming area is described in the technical scheme of the patent, the method can realize various injection forming structures except spiral, and can construct any space shape according to clinical needs.

Obviously, the technical scheme of the patent realizes the integration of the multi-step operations of puncturing, expanding, injecting the internal plant, bone cement, forming and the like in vertebroplasty, and the multiple steps are synchronously carried out, so that the operation flow is greatly optimized, the operation time is shortened, and the operation difficulty is reduced.

Examples:

Example 1:

1. preparation of materials:

a) PEEK thin-wall pipe is selected as a biocompatible polymer hollow pipe:

the outer diameter of the pipe is about 4mm and the thickness is about 1.5mm.

B) Pre-bending PEEK pipe:

i. the biocompatible polymer hollow tube 1 is closed at its initial or head end (i.e., the end that is injected into the vertebral body 0) and has a closed end 2 (shown in fig. 2) formed at its front end.

And ii, punching the inner side of the pipe to form an inner side hole 3, wherein the hole diameter of the inner side hole is matched with the flowing of bone cement by about 2mm. Because the starting end is closed, after the bone cement is injected into the pipe, the inner space of the spiral pipe can be injected through the inner hole.

Annular or serpentine cutting is performed on the surface of the pipe, and annular, serpentine or spiral cutting grooves 4 (see fig. 3) are formed on the outer surface of the pipe.

The cutting mode and depth need to ensure that the pipe wall is not damaged and the bone cement is not leaked.

C) A memory alloy guide pin 5 is inserted into the hollow tube:

The memory alloy guide pin is inserted for two purposes, namely, when the vertebral body is bent, the memory alloy is bent into a spiral shape to guide the biocompatible polymer hollow tube to be formed, most of air in the hollow tube is discharged to reduce thrombus formation, and a good bone cement injection channel is maintained to prevent the biocompatible polymer hollow tube from extruding the injection channel when the biocompatible polymer hollow tube is bent.

D. ) Thermally pre-shaping the biocompatible polymer hollow tube inserted with the needle core:

i. On the premise of annular/serpentine cutting and inner side hole reduction of the surface tension of the biocompatible polymer hollow tube, the biocompatible polymer hollow tube is pre-bent into a spiral structure (shown in fig. 4 and 5, for short, a spiral tube) by a heat setting method, wherein the outer diameter of the spiral tube 1A is adjustable, and can be prefabricated into different specifications according to requirements;

and ii, the spiral pipe after thermoforming is of a disc-shaped structure, and the spiral pipe after thermoforming is required to be positioned in a material elastic area so as to ensure complete rebound after straightening.

The actual operation implementation process comprises the following steps:

a) Injection of PEEK screw implant vertebrae:

i. the "full tray" of coils 1A is loaded into the injectable coil housing 14 of the injection gun (i.e., the push drive 7 referred to previously) and the closed start end is loaded into the bore (see fig. 6, 7).

The bore of the injection gun is connected with a puncture sleeve 6. The inner diameter of the puncture sleeve is matched with the outer diameter tolerance of the spiral pipe (namely the biocompatible polymer hollow pipe), and then the memory alloy guide pin is inserted into the biocompatible polymer hollow pipe from the muzzle to form the biocompatible polymer hollow pipe with the needle core.

By driving the injection gun, the helical biocompatible polymer hollow tube and the memory alloy guide needle can be synchronously and integrally and slowly injected (or pushed into) the vertebral body.

The PEEK pipe after heat presetting is forced to be straightened temporarily when passing through the puncture sleeve of the injection needle because the PEEK pipe is positioned in the elastic area of the material, and the PEEK pipe after heat presetting is quickly rebounded to the original curvature through the internal stress under the guidance of the memory alloy guide needle after passing through the puncture sleeve of the injection needle once, and keeps consistent with the shape (namely spiral tube shape) of the prior presetting.

B) Injection of bone cement:

after injection of the PEEK coil (also known as an injectable coil), the injection gun is replaced with a "magazine" for the injected material and filled with the mixed injectable bone cement.

Injecting a quantity of bone cement (which can be measured in advance according to the size and dimension of the prefabricated spiral tube) into the PEEK tube by operating or controlling the injection gun within the setting tolerance time of the injectable bone cement.

The amount of bone cement is carefully measured and calculated, and the volume in the hollow tube and the hollow area in the space surrounded by the spiral tube are taken in together. Ensuring that the bone cement fills all of the predetermined areas.

C) Injection gun structure (see fig. 6, 7):

i. After the driving handle 10 is pressed, the driving shaft 11 is driven, and the driving shaft is driven by the belt 12 to transmit power to the lower two driving rollers 13A (belt connection).

The upper two rollers 13B are passive rollers and are not directly powered.

And the distance between the upper roller and the lower roller is adjustable and is consistent with the outer diameter of the spiral tube. The detachable spiral tube is extruded into the puncture sleeve after being temporarily straightened.

The injectable spiral tube bin 14 is of a detachable structure, and spiral tubes with different specifications can be filled according to requirements. The "clip" structure of a firearm is similar and will not be described in detail herein.

It should be noted that the push driving device in the technical solution of the present invention is not limited to the pistol type structure shown in fig. 6 and 7, and those skilled in the art, after understanding and grasping the concept of the present invention for solving the problem, may completely use other similar devices with push and injection functions to realize the push of the PEEK spiral tube and the injection of bone cement, which will not be described in detail herein.

The injection/advancement step is illustrated with reference to fig. 8-15.

Step 1, synchronously injecting/pushing a biocompatible polymer hollow tube 1 and a memory alloy guide needle 5;

fig. 8 shows the hollow tube 1 after injection/pushing out of the puncture sleeve, under the guidance and action of the memory alloy guiding needle 5, forming a spiral (coiled) structure within the vertebral body 0.

The shape of the memory alloy guide needle 5 in the hollow tube and the guiding effect on the formation of the biocompatible polymer hollow tube are shown with emphasis in fig. 9.

Step 2, under the guidance of the memory alloy needle, the injection/pushing of the biocompatible polymer hollow tube is completed;

The hollow tube in which the spiral tube 1A has been formed in the vertebral body 0 is shown with an emphasis in fig. 10.

In fig. 11, the shape of the memory alloy guide needle and the forming guide effect on the biocompatible polymer hollow tube are shown in an emphasized manner, and the biocompatible polymer hollow tube itself is subjected to a desalination treatment in order to highlight the shape of the memory alloy guide needle.

Step 3, extracting the memory alloy needle in the biocompatible polymer hollow tube;

Fig. 12 shows with an emphasis that the memory alloy needle 5 is withdrawn from the biocompatible polymer hollow tube 1 in the direction indicated by the arrow in the drawing, so that only a hollow spiral tube 1A remains in the vertebral body 0 and has formed a spiral structure in the vertebral body, which forms the boundary of the filling space of the injectable bone substitute or serves as a boundary rail of the filling space.

And 4, injecting bone cement into the biocompatible polymer hollow tube.

In fig. 13, the spiral 1A is shown with a hollow cone and a spiral formed in the cone, and the injectable bone substitute 8 is injected through the hollow tube 1 of biocompatible polymer.

The injectable bone substitute now enters and fills only a portion of the coil's intraductal space, the remaining intraductal space of the coil remaining unfilled.

In fig. 14, the emphasis is on the injectable bone substitute 8 having been fully filled in the helical hollow tube, not yet overflowing from the inner hole of the hollow tube.

In fig. 15, a state is shown with emphasis that the injectable bone substitute 8 has completely filled the space inside the hollow tube 1 and overflowed from the inner hole.

At this time, the injectable bone substitute forms a three-dimensional filling body at the designated position in the vertebral body, and when the injectable bone substitute is solidified, a bone substitute 9 which can bear pressure and has the same or similar strength as the vertebral body at the position can be formed.

Obviously, the aforementioned helical hollow tube constitutes the injection channel for the injectable bone substitute and the boundary or boundary rail of the injectable bone substitute filling space.

In the above figures, when the biocompatible polymer hollow tube is denoted by 1, it is emphasized that it is a hollow tubular structure, and when the helical biocompatible polymer hollow tube is denoted by 1A, it is emphasized that it is a helical coil structure, and in order to highlight the hollow characteristics of the helical tube, there are cases where the helical tube portion is denoted by 1.

After the operation of the steps, the technical scheme of the invention adopts an integrated injection implementation method, and the injection method is realized by pushing/injecting the biocompatible polymer hollow tube which is used as a needle core by the memory alloy guide needle to the appointed position in the vertebral body, so as to form the boundary of the filling space of the injectable bone substitute or the boundary fence which is used as the filling space, thereby realizing the molding planability and controllability of the injectable bone substitute, avoiding the leakage risk of the injectable bone substitute, further integrally realizing the multi-step operations such as puncture, expansion, injection of the bone substitute, molding, solidification and the like in the vertebroplasty, optimizing the operation flow, shortening the operation time and reducing the operation difficulty.

Example 2:

The basic idea of solving the problems is as follows:

the basic principles of a tunnel shield machine/a tunneling machine and a flexible shaft drill are combined, a spiral tunnel is continuously tunneled in a vertebral body, then a drill bit is withdrawn from the flexible shaft tube, meanwhile, the degradable part of the flexible shaft tube is reserved in the tunnel, and finally bone cement is injected into the degradable flexible shaft tube, so that the bone cement shield of the spiral tunnel is completed.

Specifically, the implementation process is as follows:

1) Flexible shield system guided by memory alloy guide pins (also known as guide wires):

a. the system consists of a head drill 20 (see fig. 16), a central flexible shaft tube, and a tail drive (not shown).

B. The flexible shaft tube is divided into four layers, namely a degradable tube 21 as an outer layer, a wear-resistant tube 22 as a middle layer, a flexible rotating shaft 23 for driving the drill bit to rotate as an inner layer, and a hollow shaft center layer 24 (see fig. 17-18) inside the rotating shaft.

C. The space between the outer and middle layers of the flexible shaft tube may form an annular tube 25 that provides an output channel for bone chips drilled by the drill (see fig. 18, 19).

D. The guide wire (i.e., the memory alloy guide pin 5 described above) serves to guide the drill bit to follow a predetermined path, such as a spiral up or down, or any other desired path.

2) The shield implementation process comprises the following steps:

a. Flexible shield system:

i. The drill bit 20 is integrally connected with the flexible rotating shaft 23, is exposed out of the degradable tube 21 and is used for drilling and tunneling in vertebral bone. The flexible shaft tube is formed by wrapping the four-layer tubular structure layer by layer.

And ii, the outer layer tube is a degradable polymer tube, and is reserved in the vertebral body after the bone tunneling is completed, and then bone cement is injected into the outer layer tube.

Iii. middle layer tube: the outer diameter of the wear-resistant pipe is equal to the inner diameter of the outer pipe, and the wear-resistant pipe is tightly adhered to the outer pipe. And the abrasion of the rotating shaft to the outer layer degradable tube in the drilling process is prevented. After the bone tunnel tunneling is completed, the bone tunnel tunneling device is pulled out together with the inner layer driving shaft, the guide wire and the puncture needle.

The inner layer tube is a flexible rotating shaft 23 for driving the drill bit to rotate, and the diameter of the flexible rotating shaft is about half of that of the middle layer tube, and a hollow annular pipeline 25 is formed between the flexible rotating shaft and the middle layer tube for discharging bone fragments. After the bone tunnel tunneling is completed, the bone tunnel tunneling is pulled out together with the inner layer driving flexible rotating shaft, the guide wire and the puncture sleeve.

V. the axial layer is a hollow structure inside the flexible driving shaft, and the size of the axial layer can be used for the free passing of the puncture needle or the guide wire.

B. With the aid of X-ray, the puncture sleeve 6 and the puncture needle 6A therein were percutaneously advanced to the injection starting point by the method in example 1 (see fig. 20).

C. After the needle is withdrawn from the sleeve, the guide wire is threaded, and the flexible shield system is threaded through its hollow tube in the axial layer, into the sleeve, and to the injection site of the pedicle (see fig. 21).

The driving motor (not shown in the figure) of the flexible rotating shaft is started, the flexible shaft tube synchronously performs bone tunneling under the guidance of the guide wire 5 (see figure 22), and the bone fragments shielded by the shield are discharged through the annular pipeline between the middle layer and the inner layer.

The situation after the bone tunneling is completed is shown in fig. 23.

D. After tunneling, the outer layer (degradable tube) of the flexible shaft tube is reserved in the vertebral body, and simultaneously the guide wire, the drill bit and the rotating shaft connected with the drill bit and the middle layer wear-resistant tube in the flexible shaft tube are sequentially pulled out.

E. After unloading the drive (motor) at the end of the flexible shaft tube, an injectable bone substitute injection gun is mounted at the end of the outer degradable tube, wherein the injectable bone substitute comprises but is not limited to bone cement, PMMA (polymethyl methacrylate ).

F. The injectable bone substitute 8 is injected into the degradable tube until the injectable bone substitute fills the entire degradable tube 21, and the bone tunnel is completely filled with the injectable bone substitute (such as bone cement, etc.) (see fig. 24).

G. The bone cement shield (bone tunneling) structure (bone cement filling) of the vertebral body is completed. When the injectable bone substitute is cured, the remaining structure in the vertebral body is the outer layer (degradable tube) and its internal bone substitute.

As indicated above. In the technical scheme of the invention, the following two realization devices are provided:

1) The bone tunnel is not required to be drilled after the vertebral body cancellous bone is distracted when the osteoporosis or the bone loss damage to the vertebral body cancellous bone is serious and the mechanical bearing requirement is high.

The cement reinforced helical tube dual injection system given in example 1 may be used at this time. According to the scheme, through the large bone cement consumption, the outer tube made of the peek material is reinforced, and the stronger cone reinforcing and bearing effect can be formed.

2) When osteoporosis or bone loss and destruction of the cancellous bone of the vertebral body are enough and the mechanical bearing requirements are enough, the technical scheme needs to drill a bone tunnel for the target vertebral body after two adjacent vertebral bodies are spread.

The flexible bone cement shield system under the guidance of the guide wire in example 2 may be used at this time. According to the scheme, tunneling of the bone tunnel and injection of bone cement are integrally completed through convenient operation.

The technical scheme of the invention has the beneficial effects that:

1) Percutaneous minimally invasive injection/push:

The spiral tube double injection system for reinforcing the bone cement or the flexible bone cement shield system guided by the guide wire can be completed by a percutaneous minimally invasive injection mode.

2) The molding can be planned:

The two modes can be realized according to imaging, the structure, the shape and the size of an injection area can be customized before operation, and the injection area can be perfectly molded according to the preset space shape in operation and is consistent with an external scheme.

3) The molding is controllable:

a) The implantation position is controllable, the damaged area is estimated according to the compression damage degree of the vertebral body, and the area (the relative complete area of the upper cortical bone and the lower cortical bone) needing to be distracted is accurately positioned without affecting the rest area

B) The injection volume is controllable, and implantation is limited to a specific area. The injection quantity of the required bone cement can be accurately calculated, and various complications caused by bone cement leakage can be perfectly solved, and the mechanical supporting effect is uncontrollable.

C) The expanding (forming) effect is controllable, a reset scheme is formulated before operation according to the damage condition of the adjacent segment intervertebral disc and the end plate, and the expected expanding/reset effect can be accurately achieved through the selection of the optimal peek screw body model.

D) The mechanical support is controllable, the injected Peek screw body is of a closed structure, the usage amount and dispersion path of the bone cement can be strictly limited through a gap reserved for the bone cement in the injection Peek screw body, and the mechanical strength of the injection Peek screw body and the external simulation of the injection Peek screw body can be completely consistent.

4) The implementation is flexible and selectable:

a) The bone cement reinforced helical tube dual injection system may be used in vertebroplasty procedures where stronger mechanical support is required.

B) The flexible bone cement shield system guided by the guide wire can be used for vertebroplasty which requires more convenient and integrated operation.

According to the technical scheme, a degradable hollow tube serving as a 'needle core' is pushed/injected to a designated part in a vertebral body by a memory alloy guide needle to form a boundary of a bone cement filling space or serve as a boundary fence of the filling space, and the designated part in the vertebral body can be injected with bone substitutes to fill the biocompatible polymer hollow tube and the filling space surrounded by the biocompatible polymer hollow tube. The bone cement injection area has the planning property, and the multi-step operations of puncturing, expanding, injecting the endophyte, bone cement, forming and the like in the vertebroplasty are integrally realized.

The invention can be widely used in the field of design and manufacture of orthopedic implant injection devices.

Claims

1. An integrated injection device for injectable bone substitute in vertebral body shaping, characterized by:

The integrated injection device at least comprises a push drive device, a biocompatible polymer hollow tube and a linear memory alloy guide needle;

The push drive device has a straight tubular puncture sleeve, under the action of the puncture sleeve, the biocompatible polymer hollow tube and the linear memory alloy guide needle are forced to be pushed into the vertebral body in a straight structural form synchronously;

A memory alloy guide needle is arranged in the biocompatible polymer hollow tube, and the memory alloy guide needle constitutes the "needle core" of the biocompatible polymer hollow tube, so that the two become an integrated structure;

The front end of the biocompatible polymer hollow tube is closed;

Wherein, the push drive device is used to push the biocompatible polymer hollow tube and the memory alloy guide needle to the designated position inside the vertebral body;

The memory alloy guide needle is used to guide the biocompatible polymer hollow tube to bend and shape, discharge most of the air in the hollow tube, and prevent the injection channel from being squeezed when the biocompatible polymer hollow tube is bent, thereby maintaining a good injection channel for injectable bone substitutes;

The biocompatible polymer hollow tube constitutes an injection channel for the injectable bone substitute and a boundary or boundary fence of the injectable bone substitute filling space;

The integrated injection device inserts a linear memory alloy guide needle into the biocompatible polymer hollow tube for thermal preforming, and pushes the two into the vertebral body in an integrated manner. Under the guidance of the memory alloy guide needle, the biocompatible polymer hollow tube quickly rebounds to the original curvature due to internal stress, thereby forming the boundary of the space filled with the injectable bone substitute or serving as a boundary fence of the filling space; then the injectable bone substitute is injected into the designated position through the hollow tube; and then at the designated position in the vertebral body, the injectable bone substitute fills the biocompatible polymer hollow tube and the filling space surrounded by it; the injection area of the injectable bone substitute is plannable, and the puncture, distraction, injection of implants and bone cement, and molding in vertebroplasty are integrated; all steps are performed simultaneously, the operation process is optimized, the operation time is shortened, and the operation difficulty is reduced.

2. The integrated injection device for injectable bone substitute in vertebral body shaping according to claim 1, characterized in that the biocompatible polymer hollow tube and memory alloy guide needle which have been preformed by heat are placed in the push drive device after being preformed;

Insert the puncture sleeve of the push drive device to the required designated position inside the vertebral body;

The push drive device, with the aid of the puncture sleeve, continuously and synchronously delivers the prefabricated biocompatible polymer hollow tube and the memory alloy guide needle in an integrated manner;

Under the forced restraint and guidance of the straight tubular puncture sleeve, the prefabricated biocompatible polymer hollow tube and memory alloy guide needle are sent to the designated position inside the vertebral body in a straight line;

After leaving the straight tubular puncture sleeve, the biocompatible polymer hollow tube quickly rebounds to its original curvature under the guidance of the memory alloy guide needle due to internal stress, and recovers or remains consistent with the shape after thermal presetting;

The integrated injection device continuously and synchronously pushes the biocompatible polymer hollow tube and the memory alloy guide needle in an integrated manner, thereby forming an injectable bone substitute filling space inside the vertebral body, which has the same or similar shape as the biocompatible polymer hollow tube after thermal preforming.

3. The integrated injection device for injectable bone substitute in vertebral body shaping according to claim 1, characterized in that a plurality of side holes are provided on one side of the biocompatible polymer hollow tube;

When the biocompatible polymer hollow tube is thermally preformed, the side hole faces the interior of the filling space surrounded by the biocompatible polymer hollow tube;

The injectable bone substitute fills the inner space of the biocompatible polymer hollow tube by pushing or injecting;

Alternatively, the injectable bone substitute passes through the biocompatible polymer hollow tube with a plurality of side hole structures by pushing or injecting, and fills the biocompatible polymer hollow tube and the three-dimensional filling space surrounded by it.