Expandable vertebral fusion device

Abstract

The application discloses an extended vertebral body fusion device, which comprises an implanting mechanism, a pushing mechanism and a supporting mechanism. The implanting mechanism is a structure capable of being inserted into an intervertebral space between two adjacent vertebral bodies of a patient with a spinal column and capable of maintaining or expanding the intervertebral space after being inserted. The implanting mechanism is provided with an implanting cavity capable of being communicated to the intervertebral space. The pushing mechanism is a structure capable of being inserted into the implanting cavity and capable of moving back and forth along the implanting cavity after being inserted. The pushing mechanism is used for pushing and controlling the supporting mechanism to be implanted into the intervertebral space through the implanting cavity. The supporting mechanism is a structure capable of being in a contracted state inside the implanting cavity and capable of being in an expanded state outside the implanting cavity. The supporting mechanism is passively deformed and expanded into an intervertebral space supporting body after being implanted into the intervertebral space, so that the fusion with the two adjacent vertebral bodies is realized. The device can effectively overcome the problem that a flexible bag is implanted by a complex method to expand the intervertebral space in the prior art, simplifies operation steps, reduces the operation difficulty and improves the operation efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to medical devices for spinal surgery, in particular to an expandable vertebral fusion device. BACKGROUND

[0002] One of the main means of treatment for patients with spinal degenerative diseases or spinal structure damage is to perform vertebral fusion surgery, that is, to implant an intervertebral fusion cage between two adjacent vertebral bodies of the patient. The working principle of the intervertebral fusion cage is to use the expansion force of the intervertebral fusion cage to keep the muscle, annulus fibrosus and anterior and posterior longitudinal ligaments of the fusion segment in a state of continuous tension after the intervertebral fusion cage is implanted, so as to achieve three-dimensional hyperstatic fixation of the fusion segment and the intervertebral fusion cage. The intervertebral fusion cage restores the intervertebral space of the patient to the normal sequence or height, so as to restore and reconstruct the stress and stability of the anterior and middle columns of the spine, and then restore and maintain the inherent physiological lordosis of the spine, expand the intervertebral foramen, relieve the compression of the dural sac and nerve root, and eliminate the symptoms such as waist and leg pain and numbness of the patient. The hollow structure of the intervertebral fusion cage also provides a good mechanical environment for the fusion of cancellous bone inside, so as to achieve the effect of permanent interface fusion.

[0003] At present, there are many types of intervertebral fusion cages that have been applied in spinal surgery. The Chinese patent application for invention with publication number CN106983586A proposes an intervertebral fusion system through a minimally invasive approach, which aims to solve the problem that the contact area of the existing intervertebral fusion cage with the upper and lower vertebral bodies cannot be controlled, and the bone graft space is too small, which affects the fusion effect of the upper and lower vertebral bodies. The intervertebral fusion system has a bag that can be folded or telescoped. After the bag is implanted into the intervertebral disc of the patient, the bag is filled by injecting support material into the bag, and a H-shaped or rectangular support body is formed, so as to achieve the effect of steplessly adapting to the height of the intervertebral space of the patient, and the contact area with the upper and lower vertebral bodies is easy to control.

[0004] However, the above-mentioned intervertebral fusion system adjusts the height of the intervertebral space by implanting the bag first and then filling the bag, which makes the implantation of the bag more difficult due to the inherent flexibility of the bag, and the operation steps become complex, the operation time tends to be prolonged, and the operation difficulty increases accordingly. In order to solve the above-mentioned problems, medical researchers have been trying to improve and improve the existing intervertebral fusion system in order to improve the efficiency of fusion surgery, delay the progression of spinal diseases, relieve the symptoms of pain in patients, and improve the quality of life of patients, but so far no satisfactory progress has been made. SUMMARY

[0005] The purpose of the present application is to provide an expandable vertebral fusion device which is simple and stable in structure, easy to implant, can simplify the operation, mechanically expand the intervertebral space, and has safe and reliable therapeutic effect.

[0006] In order to achieve the above-mentioned purpose, the extension type vertebral fusion device is mainly composed of an implanting mechanism, a pushing mechanism and a supporting mechanism, and has the following special features:

[0007] The implanting mechanism is capable of being inserted into the intervertebral space between two adjacent vertebrae of a patient and maintaining or expanding the intervertebral space after being inserted.

[0008] The pushing mechanism is capable of being inserted into the implanting cavity and moving back and forth along the implanting cavity after being inserted.

[0009] The supporting mechanism is capable of being in a contracted state inside the implanting cavity and in an expanded state outside the implanting cavity, and is passively deformed to become an intervertebral space support after being implanted into the intervertebral space, thereby realizing fusion with the two adjacent vertebrae.

[0010] As a preferred solution:

[0011] The implanting mechanism has an implanting tube with one end capable of being inserted into the intervertebral space, an axial inner cavity of the implanting tube forming the implanting cavity, and the other end of the implanting tube being provided with a holding handle.

[0012] The pushing mechanism has an operating rod with one end capable of being inserted into the implanting cavity, and the other end of the operating rod being provided with an operating handle.

[0013] The supporting mechanism has a first connecting rod, a second connecting rod, a third connecting rod and a fourth connecting rod, the first connecting rod, the second connecting rod, the third connecting rod and the fourth connecting rod being sequentially and end-to-end hinged to form a four-connecting-rod mechanism capable of being contracted and expanded.

[0014] The hinged part of the first connecting rod and the second connecting rod is provided with a retreat gap, the hinged part of the third connecting rod and the fourth connecting rod is provided with a rod end joint, and one end of the operating rod is detachably connected to the rod end joint through the retreat gap.

[0015] More specifically described:

[0016] The first connecting rod and the second connecting rod are connected by a pair of coaxially arranged first pin shafts, and the gap between the pair of first pin shafts forms the retreat gap.

[0017] The second connecting rod and the third connecting rod are connected by a second pin shaft.

[0018] The third connecting rod and the fourth connecting rod are connected by a third pin shaft, and a threaded sleeve is arranged in the middle of the third pin shaft and arranged perpendicularly to the third pin shaft, and the threaded sleeve constitutes the rod end joint;

[0019] The fourth connecting rod and the first connecting rod are connected by a fourth pin shaft;

[0020] The threaded head is arranged at one end of the operating rod inserted into the implantation cavity, and the threaded head is detachably connected to the threaded sleeve through the retreat gap.

[0021] As another preferred solution:

[0022] A first pull rope channel is arranged in the middle of the rod body of the first connecting rod, one end of the first pull rope channel extends to the retreat gap, and the other end of the first pull rope channel is directed to the hinge of the fourth connecting rod;

[0023] The fourth connecting rod has a fourth inner connecting rod for lifting and a fourth outer connecting rod for hinge function, the fourth inner connecting rod is movably embedded in the fourth outer connecting rod, a first inclined wedge block is arranged between the fourth inner connecting rod and the fourth outer connecting rod, one end of the first inclined wedge block is connected to the first pull rope, and the other end of the first pull rope is sequentially led out along the implantation cavity through a through hole arranged on the fourth outer connecting rod, the first pull rope channel and the retreat gap;

[0024] A second pull rope channel is arranged in the middle of the rod body of the second connecting rod, one end of the second pull rope channel extends to the retreat gap, and the other end of the second pull rope channel is directed to the hinge of the third connecting rod;

[0025] The third connecting rod has a third inner connecting rod for lifting and a third outer connecting rod for hinge function, the third inner connecting rod is movably embedded in the third outer connecting rod, a second inclined wedge block is arranged between the third inner connecting rod and the third outer connecting rod, one end of the second inclined wedge block is connected to the second pull rope, and the other end of the second pull rope is sequentially led out along the implantation cavity through a through hole arranged on the third outer connecting rod, the second pull rope channel and the retreat gap.

[0026] Further, the other end of the first pull rope is led out along the implantation cavity and enters the holding handle, and is connected to a pull rope operating mechanism arranged in the holding handle; the other end of the second pull rope is led out along the implantation cavity and enters the holding handle, and is also connected to the pull rope operating mechanism arranged in the holding handle. In this way, the first inclined wedge block and the second inclined wedge block can be moved by simultaneously pulling the pull rope operating mechanism, so as to control the fourth inner connecting rod and the third inner connecting rod to be synchronously lifted to a set height.

[0027] Further, the first inclined wedge slider has a cross section in the shape of a cross, and first slider flanges are arranged at the upper and lower ends of the first inclined wedge slider and embeddedly fitted with the sliding grooves in the fourth inner connecting rod and the fourth outer connecting rod; the second inclined wedge slider has a cross section in the shape of a cross, and second slider flanges are arranged at the upper and lower ends of the second inclined wedge slider and embeddedly fitted with the sliding grooves in the third inner connecting rod and the third outer connecting rod. In this way, the structure is simple and reliable, the embedded fitting is precise, the inner and outer connecting rods can be effectively prevented from shaking, and the lifting action of the inner connecting rod is stable.

[0028] Further, a first installation through hole is formed in the center of the first inclined wedge slider, and one end of the first pull rope is fixedly connected with the first installation through hole by penetrating the first installation through hole; a second installation through hole is formed in the center of the second inclined wedge slider, and one end of the second pull rope is fixedly connected with the second installation through hole by penetrating the second installation through hole. Since the volume of the inclined wedge slider in the actual finished product is small and exquisite, the installation through hole formed in the center can increase the contact area with the corresponding pull rope, and ensure that the two are firmly and stably connected.

[0029] Further, one end of the first pull rope is provided with a first connecting cap, and the first connecting cap is riveted or welded with the first installation through hole; one end of the second pull rope is provided with a second connecting cap, and the second connecting cap is riveted or welded with the second installation through hole. In this way, the connection is stable and reliable, and the assembly is convenient and fast.

[0030] The implant tube in the above-mentioned vertebral fusion device mainly has two structural forms, the first structure is that the cross section of the implant tube is one of a square or a circle, so that the implant tube can always maintain a consistent vertical height in the intervertebral space, and ensure that the intervertebral space is always stable and unchanged. The second structure is that the cross section of the implant tube is one of a rectangle, a polygon with more than four sides, or an ellipse, so that the implant tube can change the vertical height by rotating in the intervertebral space, and force the intervertebral space to further expand, leaving enough implementation space for subsequent treatment.

[0031] The working principle of the present application is as follows: the designed expanded vertebral fusion device is specially used for the intervertebral space between two adjacent vertebral bodies of a patient with spinal column disease. During the operation, after part of the transverse process, lamina and annulus fibrosus of a vertebral body are removed, the device is inserted into the intervertebral disc in the intervertebral space. The implant mechanism can mechanically force the two adjacent vertebral bodies to separate in the direction of the spinal column axis, so that the intervertebral space can be maintained or expanded. At the same time, the implant mechanism provides an implant cavity connected to the intervertebral disc as a passage, so that the pushing mechanism can conveniently push the supporting mechanism through the passage into the intervertebral disc after the nucleus pulposus of the intervertebral disc is emptied. Furthermore, the supporting mechanism can be passively expanded under the control of the pushing mechanism, becoming an intervertebral space support body with the upper end face and the lower end face reliably abutting against the two adjacent vertebral bodies, so that the intervertebral space can be maintained at a vertical height with a therapeutic or pain-relieving effect after the implant mechanism is withdrawn.

[0032] The advantage of the present application is that the designed expansion type vertebral fusion device can conveniently operate the rigid implant mechanism to be inserted into the intervertebral space of the patient with pathological changes, and mechanically maintain or expand the intervertebral space by using the rigidity of the implant mechanism; at the same time, the pushing mechanism can quickly push the contracted support mechanism through the implant cavity into the intervertebral disc, and operate the support mechanism to mechanically expand and deform into a stable intervertebral space support body in the intervertebral disc. In this way, the technical problem of expanding the intervertebral space by implanting a flexible bag in the background art is effectively overcome, the operation steps are simplified, the surgical difficulty is reduced, and the surgical efficiency is improved. Moreover, the expansion type vertebral fusion device is composed of pure mechanical components, which has simple and exquisite structure, can be implanted into the intervertebral space with the smallest gap, avoids destructive elevation of the intervertebral space, and causes little damage to the patient's tissue; at the same time, the mechanical expansion deformation area is large and stable in support, the effect after implanting the intervertebral space is good, the recovery after surgery is fast, the progress of spinal disease can be effectively delayed, the pain symptoms of the patient can be relieved, and the life quality of the patient can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0034] Figure 2 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient. Figure 1 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0035] Figure 3 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient. Figure 1 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0036] Figure 4 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient. Figure 3 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0037] Figure 5 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient. Figure 3 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0038] Figure 6 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient. Figure 3 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0039] Figure 7 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0040] Figure 8 The figure is a schematic view of the orientation structure of the expansion type vertebral fusion device of the present application when implanted into the intervertebral space of the patient.

[0041] Figure 9 Fig. 2 is a perspective view of the height-adjustable support mechanism shown in Fig. 1 ; Figure 8 Fig. 3 is a perspective view of the height-adjustable support mechanism shown in Fig. 1 ;

[0042] Figure 10 Fig. 4 is a perspective view of the first connecting rod shown in Fig. 1 ; Figure 9 Fig. 5 is a perspective view of the first connecting rod shown in Fig. 1 ;

[0043] Figure 11 Fig. 6 is a longitudinal sectional view of the first connecting rod shown in Fig. 1 ; Figure 10 Fig. 7 is a longitudinal sectional view of the first connecting rod shown in Fig. 1 ;

[0044] Figure 12 Fig. 8 is a perspective view of the fourth outer connecting rod shown in Fig. 1 ; Figure 9 Fig. 9 is a perspective view of the fourth outer connecting rod shown in Fig. 1 ;

[0045] Figure 13 Fig. 10 is a longitudinal sectional view of the fourth outer connecting rod shown in Fig. 1 ; Figure 12 Fig. 11 is a longitudinal sectional view of the fourth outer connecting rod shown in Fig. 1 ;

[0046] Figure 14 Fig. 12 is a perspective view of the first pull rope and the first wedge block shown in Fig. 1 ; Figure 9 Fig. 13 is a perspective view of the first wedge block shown in Fig. 1 ;

[0047] Figure 15 Fig. 14 is a longitudinal sectional view of the first wedge block shown in Fig. 1 ; Figure 14 Fig. 15 is a longitudinal sectional view of the first wedge block shown in Fig. 1 ;

[0048] Figure 16 Fig. 16 is a perspective view of the second pull rope and the second wedge block shown in Fig. 1 ; Figure 9 Fig. 17 is a perspective view of the second wedge block shown in Fig. 1 ;

[0049] Figure 17 Fig. 18 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Figure 16 Fig. 19 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0050] Fig. 20 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Fig. 21 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0051] Fig. 22 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Fig. 23 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0052] Fig. 24 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Fig. 25 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0053] Fig. 26 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Fig. 27 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0054] Fig. 28 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ; Fig. 29 is a longitudinal sectional view of the second wedge block shown in Fig. 1 ;

[0055] Second pull rope passage 321, second pull rope 334, second inclined wedge block 333, second mounting through hole 335, second block flange 336, second connecting cap 337;

[0056] First pair of pin shafts 411, 412, second pin shaft 420, third pin shaft 430, fourth pin shaft 440;

[0057] Internal thread sleeve 500, intervertebral space 600, retreat gap 700. DETAILED DESCRIPTION

[0058] The application will be further described below in conjunction with the drawings and specific embodiments, but the embodiments should not be understood as limiting the application.

[0059] As Figure 1 shown:

[0060] The application describes an extended vertebral fusion device, which comprises an implanting mechanism 100, a pushing mechanism 200 and a supporting mechanism 300. The implanting mechanism 100 can intervene in the intervertebral space 600 between two adjacent vertebral bodies and maintain or expand the space, and the implanting mechanism 100 is internally provided with an implanting cavity 110 that communicates with the intervertebral space 600. The pushing mechanism 200 can be inserted into the implanting cavity 110 and move back and forth therein, for pushing and controlling the supporting mechanism 300 to implant into the intervertebral space 600 through the implanting cavity 110. The supporting mechanism 300 can be in a contracted state inside the implanting cavity 110 and in an expanded state outside the implanting cavity 110. When performing surgery on a patient, after part of the transverse process, lamina and annulus fibrosus of a vertebral body is removed, the implanting mechanism 100 is first intervened into the intervertebral space 600, for mechanically separating the two adjacent vertebral bodies in the vertical direction, so that the intervertebral space 600 can be expanded; then the supporting mechanism 300 is controlled by the pushing mechanism 200 to enter the intervertebral space 600 through the implanting cavity 110, and the supporting mechanism 300 is forced to expand into an intervertebral space support body with the upper end face and the lower end face tightly abutting against the two vertebral bodies, so that after the implanting mechanism 100 is withdrawn, the vertical height of the intervertebral space 600 at the lesion of the patient can be effectively maintained, the stress condition of the patient's spine is improved, and the compression between the two adjacent lesion vertebral bodies is reduced, thereby playing a role of treating or alleviating the patient's pain.

[0061] As Figures 2-6 shown:

[0062] The implanting mechanism 100 has an implanting tube 120 at one end that can extend into the intervertebral space 600, the axial inner cavity of the implanting tube 120 forms the implanting cavity 110, the implanting tube 120 can pass through the implanting cavity 110 to externally communicate to the position originally filled with nucleus pulposus in the intervertebral space 600 in any rotating state, and the other end of the implanting tube 120 is provided with a holding handle 130.

[0063] In a conventional selection, the cross section of the implant tube 120 can be one of a square or a circle. The circular cross section can ensure that the implant tube 120 maintains a consistent spinal vertical height when rotated at any angle within the intervertebral space 600, and the square cross section can at least ensure that the implant tube 120 maintains the same vertical height when rotated by 90° within the intervertebral space 600. These two structures are relatively simple to operate, and can ignore the rotational deviation of the implant tube 120, which is suitable for conditions where the intervertebral space 600 of the patient's lesion is relatively stable or does not change much.

[0064] In a preferred selection, the cross section of the implant tube 120 can be a rectangle or a polygon with more than four sides. The rectangular or polygonal cross section can enable the implant tube 120 to maintain a larger size position or a smaller size position in the spinal vertical direction according to the rotation state, so that the implant tube 120 can change the vertical height by rotation. Among them, the smaller size should be less than or equal to the maximum gap diameter at the intervertebral space 600 of the patient's lesion, and the larger size should be greater than the maximum gap diameter but should not exceed the limit state of the tissue expansion such as the limiting ring.

[0065] In this way, when performing vertebral fusion surgery at the intervertebral space 600 of the patient's lesion, the implant tube 120 is initially maintained in a smaller size in the spinal vertical direction, so that the implant tube 120 can be smoothly implemented into the intervertebral space 600; after the implant tube 120 is implemented into the intervertebral space 600, the implant tube 120 is rotated by 90°, so that the implant tube 120 changes from the smaller size to the larger size in the spinal vertical direction, and then the implant tube 120 can mechanically force the intervertebral space 600 to expand and eventually maintain a vertical height equal to the larger size, so that subsequent treatment can be implemented with sufficient space.

[0066] More preferably, the cross section of the implant tube 120 can be an ellipse. In addition to the above advantages, the implant tube 120 with an elliptical cross section can ensure that the intervertebral space 600 is expanded more smoothly, reducing the damage and pain caused by surgery to the patient's body.

[0067] The above pushing mechanism 200 has an operating rod 220 which can be inserted into the implant cavity 110, and the end of the operating rod 220 inserted into the implant cavity 110 is provided with a threaded head 210, and the other end of the operating rod 220 is provided with an operating handle 230.

[0068] The above support mechanism 300 adopts a four-bar linkage mechanism formed by sequentially and end-to-end hinged first, second, third and fourth connecting rods 310, 320, 330 and 340. A retreat gap is provided at the hinged portion of the first connecting rod 310 and the second connecting rod 320, and a rod end connector connected with the threaded head 210 is provided at the hinged portion of the third connecting rod 330 and the fourth connecting rod 340, and the end of the operating rod 220 threaded head 210 is detachably connected with the rod end connector through the retreat gap.

[0069] More specifically, the above-mentioned support mechanism 300 has two embodiments:

[0070] Embodiment 1

[0071] As shown in Figure 7 is a highly fixed support mechanism 300. In which: the first connecting rod 310 and the second connecting rod 320 are connected by a pair of coaxially arranged first pin shafts 411, 412, and the gap between the pair of first pin shafts 411, 412 forms the above-mentioned retreat gap 700. The second connecting rod 320 and the third connecting rod 330 are connected by a second pin shaft 420. The third connecting rod 330 and the fourth connecting rod 340 are connected by a third pin shaft 430, and the middle of the third pin shaft 430 is nested with a threaded sleeve 500 arranged vertically, which constitutes the above-mentioned rod end joint; the fourth connecting rod 340 and the first connecting rod 310 are connected by a fourth pin shaft 440.

[0072] When performing vertebral fusion surgery, the threaded head 210 at one end of the operating rod 220 is threaded into the threaded sleeve 500 through the retreat gap 700, and the support mechanism 300 is in a straight shrinkage state in the implant cavity 110, that is, all connecting rods are kept parallel to each other; after the support mechanism 300 passes through the implant cavity 110 and enters the intervertebral space 600, pulling the operating rod 220 outward will make all connecting rods rotate around the pin shaft and separate from each other to form a rhombus state, which serves as a support body abutting against the intervertebral disc in the intervertebral space 600. After the support mechanism 300 is expanded into a rhombus state, reverse rotation is performed to remove the threaded connection between the threaded head 210 and the threaded sleeve 500, so that the operating rod 220 can be withdrawn from the implant cavity 110 and the intervertebral space 600.

[0073] Embodiment 2

[0074] As shown in Figures 8-17 is another height-adjustable support mechanism 300. In which: the middle of the rod body of the first connecting rod 310 is provided with a first pull rope passage 311 extending to the retreat gap 700 at one end and to the hinge of the fourth connecting rod 340 at the other end. The fourth connecting rod 340 has a fourth inner connecting rod 341 for lifting and a fourth outer connecting rod 342 for hinge function, and the fourth inner connecting rod 341 is movably embedded in the fourth outer connecting rod 342. A first inclined wedge block 343 is arranged between the fourth inner connecting rod 341 and the fourth outer connecting rod 342, and one end of a first pull rope 344 is fixedly connected to the first inclined wedge block 343. The other end of the first pull rope 344 passes through the through hole of the fourth outer connecting rod 342, the first pull rope passage 311, the retreat gap 700, and then leads out along the implant cavity 110 (see Figures 8-13 ).

[0075] More specifically, the cross section of the first inclined sliding block 343 is in the shape of a cross, and the upper and lower ends thereof are respectively provided with first sliding block flanges 346 which are embeddedly fitted with the sliding grooves in the fourth inner connecting rod 341 and the fourth outer connecting rod 342, so as to ensure that the first inclined sliding block 343 is precisely and stably fitted with the fourth inner connecting rod 341 and the fourth outer connecting rod 342. A first mounting through hole 345 is formed in the center of the first inclined sliding block 343, and one end of the first pull rope 344 is fixedly connected with the first mounting through hole 345, so as to effectively increase the contact friction area of the two, and ensure firm connection. In the present embodiment, a first connecting cap 347 is fixed at one end of the first pull rope 344, and the first connecting cap 347 is arranged in the end sunk head of the first mounting through hole 345, and is riveted or welded therewith, which is simple and easy to operate (see Figures 14-15 ) In actual operation, the other end of the first pull rope 344 is led out along the implantation cavity 110, enters the holding handle 130, and is connected with a pull rope operating mechanism arranged in the holding handle 130 (not shown in the figure). Of course, the first pull rope 344 can also be manually or by other existing mechanical means.

[0076] Similarly, a second pull rope passage 321 is formed in the middle of the rod body of the second connecting rod 320, and one end of the second pull rope passage 321 extends to the retreat gap 700, and the other end of the second pull rope passage 321 is directed towards the hinge of the third connecting rod 330. The third connecting rod 330 has a third inner connecting rod 331 which functions to lift up and a third outer connecting rod 332 which functions to hinge, and the third inner connecting rod 331 is embeddedly arranged in the third outer connecting rod 332 in a movable manner. A second inclined sliding block 333 is arranged between the third inner connecting rod 331 and the third outer connecting rod 332, and one end of a second pull rope 334 is connected with the second inclined sliding block 333, and the other end of the second pull rope 334 is led out along the implantation cavity 110 after sequentially passing through a through hole formed in the third outer connecting rod 332, the second pull rope passage 321 and the retreat gap 700 (see Figures 8-9 ).

[0077] More specifically, the cross section of the second inclined sliding block 333 is in the shape of a cross, and the upper and lower ends thereof are respectively provided with second sliding block flanges 336 which are embeddedly fitted with the sliding grooves in the third inner connecting rod 331 and the third outer connecting rod 332, so as to ensure that the second inclined sliding block 333 is precisely and stably fitted with the third inner connecting rod 331 and the third outer connecting rod 332. A second mounting through hole 335 is formed in the center of the second inclined sliding block 333, and one end of the second pull rope 334 is fixedly connected with the second mounting through hole 335, so as to effectively increase the contact friction area of the two, and ensure firm connection. In the present embodiment, a second connecting cap 337 is arranged at one end of the second pull rope 334, and the second connecting cap 337 is arranged in the end sunk head of the second mounting through hole 335, and is riveted or welded therewith, which is simple and easy to operate (seeFigures 16-17 In actual operation, the other end of the second pull rope 334 is led out along the implantation cavity 110 and enters the handle 130, and is connected with a pull rope operating mechanism arranged in the handle 130 (not shown in the figure). Of course, the second pull rope 334 can also be manually or mechanically operated in other ways.

[0078] In the vertebral fusion operation, the operation process is basically the same as that of the first embodiment. The difference is that after the support mechanism 300 is expanded into a rhombus state by operating the lever 220, the first inclined wedge sliding block 343 can be controlled to slide along the inclined surface between the fourth inner connecting rod 341 and the fourth outer connecting rod 342 by operating the first pull rope 344, so as to realize the lifting action of the fourth inner connecting rod 341; at the same time, the second inclined wedge sliding block 333 can be controlled to slide along the inclined surface between the third inner connecting rod 331 and the third outer connecting rod 332 by operating the second pull rope 334, so as to realize the lifting action of the third inner connecting rod 331. In this way, the height in the vertical direction of the spine can be adjusted by lifting the support mechanism 300 in situ in the intervertebral space 600 to adapt to the differences in individual anatomical structures of patients, so as to ensure that the support mechanism 300 forms a closely fitted and stable intervertebral space support in the implanted intervertebral space 600, thereby realizing fusion between the adjacent two vertebral bodies.

[0079] In summary, by means of the technical solutions of the present application, the technical problems in the background art that the flexible bag needs to be implanted by complex means to expand the intervertebral space can be effectively overcome, the operation steps are simplified, the difficulty of the operation is reduced, and the efficiency of the operation is improved. At the same time, the present application has a simple and reliable structure, the mechanical expansion of the support mechanism is stable, and a stable intervertebral space support can be formed in the intervertebral disc, so as to ensure good therapeutic effect after implantation in the intervertebral space, delay the progression of spinal disease in patients, alleviate the pain symptoms of patients, and improve the quality of life of patients.

[0080] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An expandable vertebral fusion device, comprising an implant mechanism (100), a pushing mechanism (200) and a support mechanism (300), characterized in that: the implant mechanism (100) is configured to be inserted into an intervertebral space (600) between two adjacent vertebral bodies of a patient with a spinal disorder and to maintain or expand the intervertebral space (600) after the insertion, the implant mechanism (100) further comprises an implant cavity (110) which is in communication with the intervertebral space (600); the pushing mechanism (200) is configured to be inserted into the implant cavity (110) and to move back and forth along the implant cavity (110) after the insertion, the pushing mechanism (200) is used to push and control the support mechanism (300) to be implanted into the intervertebral space (600) through the implant cavity (110); the support mechanism (300) is configured to be in a contracted state inside the implant cavity (110) and to be in an expanded state outside the implant cavity (110), the support mechanism (300) is passively deformed to expand into an intervertebral support body after being implanted into the intervertebral space (600), thereby achieving fusion with the two adjacent vertebral bodies; the implant mechanism (100) has an implant tube (120) which can be inserted into the intervertebral space (600), an axial inner cavity of the implant tube (120) forms the implant cavity (110), and the implant tube (120) is provided with a holding handle (130) at the other end; the pushing mechanism (200) has an operating rod (220) which can be inserted into the implant cavity (110), and the operating rod (220) is provided with an operating handle (230) at the other end; the support mechanism (300) has a first connecting rod (310), a second connecting rod (320), a third connecting rod (330) and a fourth connecting rod (340), the first connecting rod (310), the second connecting rod (320), the third connecting rod (330) and the fourth connecting rod (340) are sequentially and end-to-end hinged to form a four-connecting-rod mechanism which can be contracted and expanded; the hinged part of the first connecting rod (310) and the second connecting rod (320) is provided with a retreat gap, the hinged part of the third connecting rod (330) and the fourth connecting rod (340) is provided with a rod end joint, and one end of the operating rod (220) is detachably connected to the rod end joint through the retreat gap; the first connecting rod (310) and the second connecting rod (320) are hingedly connected through a pair of coaxially arranged first pin shafts (411, 412), and the gap between the pair of first pin shafts (411, 412) forms the retreat gap (700); the second connecting rod (320) and the third connecting rod (330) are hingedly connected through a second pin shaft (420); the third connecting rod (330) and the fourth connecting rod (340) are hingedly connected through a third pin shaft (430), and a middle part of the third pin shaft (430) is provided with an internally threaded sleeve (500) which is arranged perpendicularly to the third pin shaft (430), the internally threaded sleeve (500) constitutes the rod end joint. The fourth connecting rod (340) is connected with the first connecting rod (310) through a fourth pin (440); The operation rod (220) is provided with a threaded head (210) at one end inserted into the implant cavity (110); the threaded head (210) is detachably connected with the internally threaded sleeve (500) through the retreat gap (700); A first pull rope channel (311) is formed in the middle of the first connecting rod (310); one end of the first pull rope channel (311) extends to the retreat gap (700), and the other end of the first pull rope channel (311) is directed to the hinge of the fourth connecting rod (340); The fourth connecting rod (340) has a fourth inner connecting rod (341) for lifting and a fourth outer connecting rod (342) for hinge connection; the fourth inner connecting rod (341) is movably embedded in the fourth outer connecting rod (342); a first inclined wedge block (343) is arranged between the fourth inner connecting rod (341) and the fourth outer connecting rod (342); one end of the first inclined wedge block (343) is connected with the first pull rope (344) provided with a first connecting cap (347); the other end of the first pull rope (344) is sequentially led out of the implant cavity (110) through a through hole formed in the fourth outer connecting rod (342), the first pull rope channel (311), and the retreat gap (700); A second pull rope channel (321) is formed in the middle of the second connecting rod (320); one end of the second pull rope channel (321) extends to the retreat gap (700), and the other end of the second pull rope channel (321) is directed to the hinge of the third connecting rod (330); The third connecting rod (330) has a third inner connecting rod (331) for lifting and a third outer connecting rod (332) for hinge connection; the third inner connecting rod (331) is movably embedded in the third outer connecting rod (332); a second inclined wedge block (333) is arranged between the third inner connecting rod (331) and the third outer connecting rod (332); one end of the second inclined wedge block (333) is connected with the second pull rope (334); the other end of the second pull rope (334) is sequentially led out of the implant cavity (110) through a through hole formed in the third outer connecting rod (332), the second pull rope channel (321), and the retreat gap (700); The other end of the first pull rope (344) is led into the holding handle (130) after being led out of the implant cavity (110) and connected with a pull rope operation mechanism arranged in the holding handle (130); The other end of the second pull rope (334) is led into the holding handle (130) after being led out of the implant cavity (110) and also connected with the pull rope operation mechanism arranged in the holding handle (130).

2. The expandable intervertebral fusion device of claim 1, wherein: The cross section of the first inclined wedge slider (343) is a cross structure, and the upper and lower ends are respectively provided with a first slider flange (346) embedded with a sliding groove in the fourth inner connecting rod (341) and the fourth outer connecting rod (342); The cross section of the second inclined wedge slider (333) is a cross structure, and the upper and lower ends are respectively provided with a second slider flange (336) embedded with a sliding groove in the third inner connecting rod (331) and the third outer connecting rod (332).

3. The expansible vertebral fusion device according to claim 2, wherein: The center of the first inclined wedge slider (343) is provided with a first installation through hole (345), and one end of the first pull rope (344) is fixedly connected with the first installation through hole (345) through the first installation through hole (345); The center of the second inclined wedge slider (333) is provided with a second installation through hole (335), and one end of the second pull rope (334) is fixedly connected with the second installation through hole (335) through the second installation through hole (335).

4. The expansible vertebral fusion device according to claim 3, wherein: The first connecting cap (347) is riveted or welded with the first installation through hole (345); One end of the second pull rope (334) is provided with a second connecting cap (337), and the second connecting cap (337) is riveted or welded with the second installation through hole (335).

5. The expansible vertebral fusion device according to any one of claims 1-4, wherein: The cross section of the implant tube (120) is one of a square or a circle, so that the implant tube (120) can always maintain a consistent vertical height in the intervertebral space (600).

6. The expansible vertebral fusion device according to any one of claims 1-4, wherein: The cross section of the implant tube (120) is one of a rectangle, a polygon with more than four sides, or an ellipse, so that the implant tube (120) can change the vertical height by rotating in the intervertebral space (600).

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