CN107049565B

CN107049565B - Centrum fusion mechanism for entering way through minimally invasive access

Info

Publication number: CN107049565B
Application number: CN201710298566.0A
Authority: CN
Inventors: 吕世文; 邓双; 毛克亚; 汪宇; 张鹏云
Original assignee: NINGBO HICREN BIOTECHNOLOGY CO LTD
Current assignee: NINGBO HICREN BIOTECHNOLOGY CO LTD
Priority date: 2017-04-28
Filing date: 2017-04-28
Publication date: 2020-04-21
Anticipated expiration: 2037-04-28
Also published as: CN107049565A

Abstract

The invention relates to a vertebral body fusion mechanism accessed through a minimally invasive access, which comprises a bag and a supporting material, wherein the bag can be folded or contracted, an injection port is arranged at one end of the bag, the supporting material is injected into the bag through the injection port, the bag is of a cylindrical structure in an inflated state, the surfaces of the bag, which are contacted with upper and lower vertebral bodies, are vertebral body contact surfaces, a contractible limiting mechanism is arranged in the circumferential direction of the bag, the diameter of the contractible limiting mechanism is smaller than or equal to the diameter of the bag in a natural inflated state, and when the bag is implanted into an intervertebral disc and the injection of the supporting material is completed, the section of the bag, which is vertical to the vertebral body contact surface, is of an I shape or a; the problem that the fusion effect of the upper vertebral body and the lower vertebral body is influenced due to the fact that the bone grafting space is too small because the contact area of the fusion cage and the upper vertebral body and the lower vertebral body cannot be controlled is solved; can realize stepless adaptation to the height of the intervertebral space and the controllable contact area with the upper and lower vertebral bodies.

Description

Centrum fusion mechanism for entering way through minimally invasive access

Technical Field

The invention relates to the field of spinal interbody fusion, in particular to a vertebral body fusion mechanism accessed through a minimally invasive access.

Background

Degenerative spinal diseases and structural damage are important causes of pain in the neck, shoulders, waist and legs, and impaired or even lost sensory and motor functions. In the last 50 s, Cloward first proposed posterior lumbar fusion (PLIF), a technique developed as one of the basic surgical procedures for spinal surgery today. Badgy and Kuslich designed an interbody fusion Cage (Cage) suitable for use in humans in 1986, the BAK system. Since then, the interbody bone-grafting fusion technology has been greatly developed, and becomes a basic operation mode for treating spinal degenerative diseases and structural injuries.

The principle of the interbody fusion cage is that after the interbody fusion cage is implanted, the muscle, the fibrous ring and the anterior and posterior longitudinal ligaments of the fusion segment are in a continuous tension state by the distraction force, so that the fusion segment and the fusion cage achieve three-dimensional super-static fixation. And secondly, the intervertebral fusion cage recovers the stress and the stability of the front and middle columns of the spine, recovers and maintains the inherent physiological bulge of the spine, enlarges intervertebral foramen and relieves the pressure of the dural sac and nerve roots by recovering the height of the intervertebral space. The hollow structure of the intervertebral fusion cage provides a good mechanical environment for the fusion of the cancellous bone therein, thereby achieving the purpose of interface permanent fusion.

The existing conventional fusion cage is generally of a box-type structure with a fixed shape, adapts to different vertebral body gaps by depending on a series of models with different heights and cannot be completely matched with the vertebral body gaps of patients; but also can not change the shape, has larger wound when being implanted, has larger damage to patients and slow postoperative recovery.

Some designs of fusion cage that can be expanded have emerged in response to the deficiencies of the product construction described above. For example, chinese patent CN 105380735 a discloses an intervertebral filling fusion device for filling between any two adjacent vertebral endplates of a human lumbar vertebra, which comprises a receiving member and a mesh body disposed at the periphery of the receiving member, and when in use, a first filler with self-solidifying property is filled between the receiving member and the mesh body. However, no limiting structure is arranged on the periphery of the mesh body, and when the self-solidifying first filler is filled, the expanded shape of the mesh body is uncontrollable, so that the contact area with the upper vertebral body and the lower vertebral body cannot be controlled, and the bone grafting space is too small to influence the fusion effect of the upper vertebral body and the lower vertebral body.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention provides a vertebral body fusion mechanism capable of achieving stepless adaptation to the intervertebral height and accessing through a minimally invasive approach with controllable contact area with the upper and lower vertebral bodies.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a vertebral body fusion mechanism entering a way through a minimally invasive access comprises a bag and a supporting material, wherein the bag can be folded or contracted, an injection port is formed in one end of the bag, the supporting material is injected into the bag through the injection port, the bag is of a cylindrical structure in a filling state, the surfaces of the bag, which are in contact with an upper vertebral body and a lower vertebral body, are vertebral body contact surfaces, a contractible limiting mechanism is arranged in the circumferential direction of the bag, the diameter of the contractible limiting mechanism is smaller than or equal to the diameter of the bag in a natural filling state, and when the bag is implanted into an intervertebral disc and the injection of the supporting material is completed, the section, perpendicular to the vertebral body contact surface, of the bag is I-shaped or rectangular.

The purpose of the invention can be further realized by the following technical scheme:

preferably, the retractable restraining mechanism is a circumferential support.

Preferably, the annular support is a plurality of parallel rings or a lattice structure.

Preferably, the pocket is provided with a through hole in a direction perpendicular to the vertebral body contacting surface.

Preferably, the space defined by the through hole is a bone graft compartment, which is isolated from the inner space of the pouch.

Preferably, there are a plurality of the through-holes, and a communication passage is provided between the plurality of the through-holes.

Preferably, an anti-slip structure is provided on the vertebral body contact surface.

Preferably, the anti-slip structure is a mesh-shaped sheet, and the support material protrudes from the lattices of the mesh-shaped sheet under a force to form anti-slip projections.

Preferably, the anti-slip structure is a compressible sheet, and barbs or protrusions are arranged on the surface of the compressible sheet, which is in contact with the vertebral body.

Preferably, the anti-slip structure is a barb or a protrusion fixed to a surface of the pouch.

Preferably, a check valve is provided on the injection port.

Preferably, the support material is a self-setting bone filler material.

Compared with the prior art, the invention has the following advantages and progresses:

1. the vertebral body fusion mechanism entering the way through the minimally invasive access forms a fusion cage in a mode of injecting supporting materials into the foldable or contractible bag capsule, and can realize stepless rise so as to adapt to different intervertebral spaces.

2. The retractable limiting mechanism is arranged in the circumferential direction of the vertebral body fusion mechanism accessed through the minimally invasive access, and the section of the retractable limiting mechanism perpendicular to the vertebral body contact surface is limited to be I-shaped or rectangular, so that on one hand, the size of the contact surface of the vertebral body fusion mechanism and the vertebral body is controlled, and on the other hand, the bone grafting space as large as possible is reserved under the condition that the size of the vertebral body contact surface is the same.

3. The vertebral body fusion mechanism accessed through the minimally invasive access comprises the foldable or contractible bag and the contractible limiting mechanism, is compressible as a whole, can enter the intervertebral space through the minimally invasive channel, and then expands and opens in the intervertebral space, so that the wound of a patient is smaller during the operation, and the recovery after the operation is facilitated.

4. According to the vertebral body fusion mechanism accessed through the minimally invasive access, 1 or more through holes are formed in the bag in the direction perpendicular to the contact surface of the vertebral body, the space defined by the through holes is a bone grafting bin, and the plurality of bone grafting bins are beneficial to injection of subsequent bone active substances.

5. According to the vertebral body fusion mechanism entering the way through the minimally invasive access, the anti-skidding structure is arranged on the vertebral body contact surface, so that the vertebral body fusion mechanism can be effectively prevented from moving after being implanted into a body.

6. The injection tube of the vertebral body fusion mechanism which enters the way through the minimally invasive access comprises an inner tube and an outer tube, wherein the far end of the outer tube is provided with an elastic bayonet which is connected with a connector of an injection port in a buckling mode, so that the phenomenon that the operation is influenced due to separation caused by mistaken rotation caused by threaded connection can be avoided, and the wall of a filler conveying tube is thinner by replacing threads through the design of the elastic bayonet.

7. The injection port of the vertebral body fusion mechanism accessed through the minimally invasive access is provided with the check valve, so that the supporting material filled in the bag can be prevented from leaking.

Drawings

FIG. 1a is a schematic view of a vertebral body fusion mechanism accessed through a minimally invasive approach in an "I" shape in cross-section perpendicular to the vertebral body contact surface;

FIG. 1b is a schematic view of a vertebral body fusion mechanism accessed via a minimally invasive approach having a rectangular cross-section perpendicular to the vertebral body contact surface;

FIG. 2a is a schematic structural view of a first retractable restraining mechanism;

FIG. 2b is a schematic structural view of a second retractable restraining mechanism;

FIG. 2c is a cross-sectional elevation view of a third retractable restraint mechanism;

FIG. 3a is a schematic structural view of a first type of through-hole;

FIG. 3b is a schematic structural view of a second type of through-hole;

FIG. 4a is a schematic illustration of a first bone active substance delivery modality of the vertebral body fusion mechanism;

FIG. 4b is a schematic illustration of a second bone active substance delivery modality of the vertebral body fusion mechanism;

FIG. 5a is a schematic view of the syringe of the vertebral body fusion mechanism;

FIG. 5b is an enlarged partial view of the distal end of the outer tube of the syringe of the vertebral body fusion mechanism;

FIG. 6a is a schematic structural view of a sheet material with a grid-shaped anti-slip structure;

FIG. 6b is a schematic view of a non-slip structure that is a compressible sheet;

wherein, 1 is a bag, 2 is a retractable limiting mechanism, 3 is an injection tube, 11 is a supporting material, 12 is an injection port, 13 is an anti-skid structure, 14 is a connecting head, 15 is a bone grafting bin, 16 is a first through hole, 17 is a second through hole, 21 is a grid structure, 22 is a ring, 23 is a non-extensible flexible wire or wire, 31 is an inner tube, 32 is an outer tube, and 321 is an elastic bayonet.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail below with reference to the accompanying drawings and examples.

As shown in fig. 1a and 1b, a vertebral body fusion mechanism accessed through a minimally invasive access comprises a bag 1 and a supporting material, wherein the bag 1 can be folded or contracted, an injection port 12 is arranged at one end of the bag 1, the supporting material 11 is injected into the bag 1 through the injection port 12, the bag 1 is in a cylindrical structure in an inflated state, the surfaces of the bag 1, which are contacted with upper and lower vertebral bodies, are vertebral body contact surfaces, and a contractible limiting mechanism 2 is arranged in the circumferential direction of the bag 1, as shown in fig. 1a, when the diameter of the contractible limiting mechanism 2 is smaller than that in a natural inflated state of the bag 1, the section of the bag 1, which is perpendicular to the vertebral body contact surface, is in an "i" shape after the bag 1 is implanted into an intervertebral disc and the injection of the supporting material 11 is completed. When the diameter of the collapsible restraining means 2 is equal to the diameter of the bag 1 in its natural filling state, as shown in figure 1b, the cross-section of the bag 1 perpendicular to the vertebral body contacting surface is rectangular after implantation of the bag 1 in the intervertebral disc and completion of the injection of the supporting material 11.

The pouch 1 may be woven from implantable filaments, such as a woven body of PET wires; it may also be a membrane balloon made of an implantable material, such as sintered PTFE. By injecting a support material into the pouch 1, the vertebral body fusion device can be made to accommodate different vertebral body spaces without any step.

As shown in fig. 2c, the support material 11 is a self-setting bone filler material, such as bone cement. The support material 11 is in a fluid state during injection, and the support material 11 is injected into the bladder 1 such that the support material 1 self-solidifies within a short period of time after the desired cylindrical configuration is achieved, thereby providing stable support between the upper and lower vertebral bodies.

The contractible limiting mechanism 2 on the circumferential surface of the bag 1 ensures that the bag 1 is limited in the outer diameter direction when being expanded, and simultaneously the upper and lower vertebral bodies limit the expansion of the bag in the height direction, so when the diameter of the contractible limiting mechanism 2 is smaller than that of the bag 1 in the natural filling state, after the bag 1 is implanted into an intervertebral disc and the injection of the supporting material 11 is completed, the section of the bag 1, which is vertical to the contact surface of the vertebral bodies, is in an I shape as shown in figure 1 a. Therefore, the shape and the size of the contact surface of the implant and the vertebral body are effectively controlled, and under the condition of the same vertebral body contact surface, more bone grafting volume can be obtained because the side surface of the I-shaped structure is inwards sunken.

In one embodiment, as shown in fig. 2a, the retractable positioning mechanism 2 is a grid structure 21 made of hollow elastic tube or woven elastic wire, the grid structure 21 is a circular ring with upper and lower openings and is fixed on the circumferential surface of the bag 1 by means of bonding or sewing, and this connection can avoid complex mechanical fastening, so that the overall size of the vertebral body fusion mechanism is small after compression. When the retractable limiting mechanism 2 is a structure which is retracted along the diameter direction, the vertebral body fusion mechanism directly injects a supporting material after being implanted into the intervertebral space, and the supporting material is expanded and then stands between the upper vertebral body and the lower vertebral body; when the retractable limiting mechanism 2 is a structure which is retracted along the axis, the vertebral body fusion mechanism needs to be turned up after being implanted into the intervertebral space, and then the supporting material is injected to support between the upper vertebral body and the lower vertebral body.

As shown in fig. 2b, the collapsible stop structure 2 may also be a plurality of parallel loops 22 arranged on the circumferential surface of the bag 1 to limit the inflated shape of the bag.

In another embodiment, as shown in fig. 2c, the retractable position-limiting mechanism 2 is a plurality of non-malleable flexible wires or filaments 23, which are radially connected to the circumferential surface of the bag 1 to limit the outer diameter of the bag 1, and the cross section of the bag 1 perpendicular to the vertebral body contact surface is I-shaped or rectangular after the upper and lower vertebral body position limitation, so that the shape and size of the vertebral body contact surface can be effectively controlled.

Bag 1 is along the perpendicular to still be provided with the through hole in the direction of vertebra body contact surface, when bag 1 is in the natural filling state the through hole extends to upper and lower centrum contact surface, the space that the through hole was injectd is bone grafting storehouse 15, its with the inside filling space mutual isolation of bag can be to the interior injection bone active material of bone grafting storehouse 15 messenger upper and lower centrum fusion. As shown in fig. 3a, the through-hole may be circular or may have another shape, such as a square shape. As shown in fig. 3b, there may be a plurality of through holes, and a communication passage is provided between the plurality of through holes. The plurality of bone grafting bins are beneficial to the injection of the subsequent bone active substances.

As shown in figure 4a, a second through hole 17 communicated with the bone grafting bin 15 is arranged on the peripheral surface of the bag 1, the injection port 12 is arranged beside the second through hole 17, after the supporting material 11 is injected into the bag 1 through the injection tube 3, a filling tube filled with bone active substances can be inserted into the second through hole 17, and the implantation of the whole vertebral body fusion mechanism is completed.

As shown in figure 4b, the first through hole 16 communicated with the bone grafting bin 15 is arranged on the peripheral surface of the bag 1, the injection port 12 is arranged on the peripheral surface of the through hole forming the bone grafting bin and is coaxial with the first through hole 16, so that the injection tube 3 for injecting the supporting material 11 and the filling tube for filling the bone active substance can be sleeved together when being preassembled, and when in use, after the supporting material 11 is injected, the injection tube 3 can be pulled out to fill the bone active substance, and the operation is simple and continuous.

In one embodiment, a check valve is provided on the injection port 12 to prevent the support material filled in the bladder from leaking. The check valve is a one-way valve.

As shown in fig. 5a and 5b, a connector 14 is disposed at the injection port 12, and the connector 14 is detachably connected with the injection tube 3. The detachable connection may be a threaded connection or a snap-in connection. As shown in fig. 5a, the injection tube 3 includes an inner tube 31 and an outer tube 32, the outer tube 32 is sleeved on the inner tube 31 and moves axially relative to the inner tube 31, an elastic bayonet 321 is disposed at a distal end of the outer tube 32, and the distal end of the inner tube 31 is connected with the connector 14 in a snap-fit manner through the elastic bayonet 321. When the inner tube 31 extends out of the elastic bayonet 321, the elastic bayonet 321 is expanded by force to adaptively match the connector 14 to realize fixed connection. As shown in FIG. 5b, when the inner tube 31 is retracted away from the elastic latch 321, the elastic latch 321 is not forced to return to close, and automatically disengages from the connector 14, so that the syringe 3 can be removed entirely. The elastic bayonet 321 arranged at the distal end of the outer tube 32 is snap-connected with the connector 14 of the injection port 12, so that not only can the operation be prevented from being influenced by the separation caused by the false rotation caused by the threaded connection, but also the overall wall of the injection tube 3 can be thinner by replacing the threads with the elastic bayonet.

In order to prevent the vertebral body fusion mechanism from moving after being implanted into the body, an anti-slip structure 13 is arranged on the vertebral body contact surface of the bag 1, as shown in fig. 6a and 6b, the anti-slip structure 13 is an agnail or a bulge fixed on the surface of the bag, and is embedded with the upper vertebral body surface and the lower vertebral body surface to prevent the vertebral body fusion system from moving; as shown in FIG. 6a, the non-slip structure 13 may also be a mesh sheet, the support material 11 being forced to protrude from the cells of the mesh sheet to form non-slip protrusions when the bag 1 is inflated; as shown in fig. 6b, the anti-slip structure 13 is a compressible sheet provided outside the bag 1, and barbs or protrusions are provided on the surface of the compressible sheet contacting the vertebral body.

Finally, it should be understood that the above-mentioned embodiments are merely preferred embodiments of the present invention, and not intended to limit the present invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A vertebral body fusion mechanism accessed through a minimally invasive access is characterized in that: the anti-skid bag comprises a bag (1) and a supporting material (11), wherein the bag (1) can be folded or contracted, an injection port (12) is arranged at one end of the bag (1), the supporting material (11) is injected into the bag (1) through the injection port (12) so as to provide stable support between upper and lower vertebral bodies, the bag (1) is of a cylindrical structure in a filling state, the surfaces of the bag (1) contacting with the upper and lower vertebral bodies are vertebral body contact surfaces, an anti-skid structure (13) is arranged on the vertebral body contact surface, the anti-skid structure (13) is a grid-shaped sheet or a compressible sheet, a contractible limiting mechanism (2) is arranged in the circumferential direction of the bag (1), the contractible limiting mechanism (2) is a ring-shaped stent, and the diameter of the contractible limiting mechanism (2) is smaller than or equal to the diameter of the bag (1) in a natural filling state, when the bag (1) is implanted into an intervertebral disc and the injection of the supporting material (11) is completed, the bag (1) can realize stepless lifting and the contact area with the upper vertebral body and the lower vertebral body is controllable, and the section of the bag (1) vertical to the contact surface of the vertebral bodies is I-shaped or rectangular.

2. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: the annular support is a plurality of parallel rings (22).

3. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: the annular support is a lattice structure (21).

4. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: the bag (1) is provided with a through hole along the direction vertical to the contact surface of the vertebral body.

5. The minimally invasive access vertebral body fusion mechanism of claim 4, wherein: the space defined by the through hole is a bone grafting bin (15), and the bone grafting bin (15) is isolated from the inner space of the bag (1).

6. The minimally invasive access vertebral body fusion mechanism of claim 4, wherein: the through holes are provided with a plurality of through holes, and communication channels are arranged among the through holes.

7. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: the supporting material (11) is stressed to protrude from the lattices of the grid-shaped sheet to form anti-skid projections.

8. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: barbs are arranged on the contact surface of the compressible sheet and the vertebral body.

9. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: and arranging a bulge on the surface of the compressible sheet, which is in contact with the vertebral body.

10. The minimally invasive access vertebral body fusion mechanism of claim 1, wherein: a check valve is arranged on the injection port (12).

11. The minimally invasive access vertebral body fusion mechanism according to any one of claims 1-10 wherein: the support material (11) is a self-setting bone filler material.