CN114271998A

CN114271998A - Distractable intervertebral fusion device

Info

Publication number: CN114271998A
Application number: CN202111520400.1A
Authority: CN
Inventors: 杨强; 许书富; 马信龙; 程磊; 董骧; 甄超; 张勋
Original assignee: TIANJIN HOSPITAL
Current assignee: TIANJIN HOSPITAL
Priority date: 2021-12-13
Filing date: 2021-12-13
Publication date: 2022-04-05

Abstract

The invention discloses a distractable interbody fusion cage, which belongs to the technical field of orthopedic implants and comprises a fusion cage main body frame, wherein distraction bodies are arranged above and/or below the fusion cage main body frame, porous structures or convex teeth are arranged on the distraction bodies, two sets of distraction structures are arranged in parallel on the left and right in the fusion cage main body frame, one set of the two sets of distraction structures is in driving connection with the left side of the distraction body, the other set of the distraction structures is in driving connection with the right side of the distraction body, so that the distraction height of the left side or the right side of the distraction body is respectively adjusted through the two sets of distraction structures, at least one set of distraction structure comprises a driving shaft and a push block sleeved on the driving shaft, a connecting rod is arranged between the push block and the distraction body, and two ends of the connecting rod are respectively hinged with the push block and the distraction body. The distractable intervertebral fusion cage can treat scoliosis, relieve compression, recover the height and tension of vertebral segments, recover the physiological curvature of the spine and ensure the stability of the spine.

Description

Distractable intervertebral fusion device

Technical Field

The invention relates to the technical field of orthopedic implants, in particular to an intervertebral cage capable of being expanded.

Background

The lumbar intervertebral fusion can effectively treat the characteristics of lumbar degeneration, instability and the like, can fuse the upper vertebral body and the lower vertebral body, maintain the intervertebral space height, relieve the pressure of nerve roots and maintain the stability of the vertebral column. The clinical effect is satisfactory, the operation wound is small, and the operation is convenient.

With the popularization of clinical application and the progress of theoretical research in recent years, the conventional fusion cage is gradually found to have certain defects, such as poor self-stability of the intervertebral implant, unsatisfactory lumbar lordosis recovery after vertebral body fusion and the like.

In order to solve the problems, the existing intervertebral fusion cage which can be expanded is adopted at present, although the existing intervertebral fusion cage which can be expanded on the market can effectively ensure the height of intervertebral space and relieve the symptoms of compression caused by vertebral bodies, the intervertebral fusion cage is basically expanded from the front side to the back side, and has defects in the treatment of symptoms such as scoliosis and the like.

Disclosure of Invention

The invention aims to solve the technical problem of providing a distractable intervertebral fusion device capable of treating scoliosis.

In order to solve the technical problems, the invention provides the following technical scheme:

the utility model provides a can strut interbody fusion cage, includes fusion cage main part frame, the top and/or the below of fusion cage main part frame are equipped with the distraction body, be equipped with porous structure or dogtooth on the distraction body, wherein:

fuse and be provided with two sets of structures of strutting side by side about in the ware main part frame, two sets of structures of strutting one of them one set with the left side drive of the body of strutting is connected, another set with the right side drive of the body of strutting is connected to strut the structure through two sets and adjust respectively strut body left side or right side and strut the height, strut in the structure at least one set and strut the structure and include the drive shaft and overlap and establish in the drive shaft by drive shaft drive connects and can follow the ejector pad that the length direction of fusing ware main part frame removed, the ejector pad with it is provided with the connecting rod to strut between the body, the both ends of connecting rod respectively with the ejector pad with strut the body articulated.

Furthermore, at least one of the propping body and the connecting rod and the pushing block and the connecting rod is a multi-degree-of-freedom hinge structure, and the multi-degree-of-freedom hinge structure enables the connecting rod to swing back and forth in the vertical direction relative to the fusion cage main body frame and the propping body to swing left and right in the vertical direction relative to the pushing block.

Furthermore, a multi-degree-of-freedom hinge structure is arranged between the spreading body and the connecting rod, and the multi-degree-of-freedom hinge structure enables the connecting rod to swing back and forth in the vertical direction relative to the spreading body and enables the spreading body to swing left and right in the vertical direction relative to the connecting rod;

or a multi-degree-of-freedom hinge structure is arranged between the push block and the connecting rod, and the multi-degree-of-freedom hinge structure enables the connecting rod to swing back and forth relative to the push block in the vertical direction and enables the connecting rod to swing left and right relative to the push block in the vertical direction.

Furthermore, a rotating shaft extending along the length direction of the opening body is fixedly arranged on the side face of the opening body, a hinge block is rotatably assembled on the rotating shaft, and the upper end of the connecting rod is hinged with the hinge block, so that the multiple-degree-of-freedom hinge structure is formed between the opening body and the connecting rod;

or the side surface of the spreading body is rotatably provided with a rotating shaft extending along the length direction of the spreading body, a hinge block is fixedly arranged on the rotating shaft, and the upper end of the connecting rod is hinged with the hinge block, so that the multi-degree-of-freedom hinge structure is formed between the spreading body and the connecting rod;

or the upper end of the connecting rod is in ball hinge joint with the side surface of the opening body.

Furthermore, the side of the strutting body is provided with a groove, and the hinging block is positioned at the groove.

Furthermore, the distraction body comprises an upper distraction body positioned above the fusion cage main body frame, one set of distraction structure comprises a first driving shaft and a first push block which is sleeved on the first driving shaft and can move along the length direction of the first driving shaft by being driven and connected by the first driving shaft, the other set of distraction structure comprises a second driving shaft and a second push block which is sleeved on the second driving shaft and can move along the length direction of the second driving shaft by being driven and connected by the second driving shaft, and the connecting rod comprises a first upper connecting rod which is hinged between the first push block and one side of the upper distraction body and a second upper connecting rod which is hinged between the second push block and the other side of the upper distraction body;

and/or, prop up the body including being located prop up the body down below the fuse ware main part frame, wherein one set props up the structure and includes that third drive shaft and cover establish in the third drive shaft by third drive shaft drive connection can be followed the third ejector pad that the length direction of third drive shaft removed, another set prop up the structure and include that fourth drive shaft and cover establish in the fourth drive shaft by fourth drive shaft drive connection can be followed the fourth ejector pad that the length direction of fourth drive shaft removed, the connecting rod is in including articulated setting third ejector pad and the lower first lower connecting rod that props up between body one side and articulated setting are in second lower connecting rod between fourth ejector pad and the lower body opposite side of propping up.

Furthermore, the first driving shaft and the third driving shaft are the same driving shaft, the first pushing block and the third pushing block are the same pushing block, the second driving shaft and the fourth driving shaft are the same driving shaft, and the second pushing block and the fourth pushing block are the same pushing block.

Furthermore, the rear part of the fusion cage main body frame is provided with a pair of rear driving shaft mounting holes which are used for being in threaded connection with the rear ends of the first driving shaft and the second driving shaft respectively in parallel, the front part of the fusion cage main body frame is provided with a pair of front driving shaft mounting holes which are used for being in sliding connection with the front ends of the first driving shaft and the second driving shaft respectively in parallel, each driving shaft is fixedly provided with a push block ladder, and the push block on each driving shaft is positioned in front of or behind the push block ladder.

Furthermore, the number of the push blocks on the first driving shaft and the number of the push block steps are two and are respectively positioned at the front part and the rear part of the first driving shaft;

the number of the push blocks on the second driving shaft and the number of the push block steps are two and are respectively positioned at the front part and the rear part of the second driving shaft.

Further, when the expandable intervertebral fusion device is not expanded, the front end point of the expanding body is positioned at 1/2-1/3 of the total length of the expandable intervertebral fusion device;

and/or the outer surface of the distraction body is provided with an inclined plane which gradually decreases from the front end to the rear end of the fusion device main body frame, and the inclination angle of the inclined plane is 1-7 degrees;

further, the distractor includes a solid outer frame region and a porous structure region within the solid outer frame region.

The invention has the following beneficial effects:

according to the distractable intervertebral fusion cage, the two sets of distraction structures for respectively adjusting the distraction heights of the left side or the right side of the distraction body are arranged in parallel on the left and the right sides in the fusion cage main body frame, so that the distraction bodies can be distracted in parallel, the left and the right sides of the distraction bodies can be distracted respectively, scoliosis can be treated, compression is relieved, the height and the tension of a vertebral segment are restored, the physiological curvature of a spine is restored, the stability of the spine is guaranteed, the fixation performance of the fusion cage is good, the fusion performance is good, and the clinical requirements are met.

Drawings

Fig. 1 is a schematic structural view of the distractable intervertebral cage of the present invention in a closed state, wherein (a) is a side view and (b) is a side sectional view;

FIG. 2 is a schematic structural view of the distracting intervertebral cage of the present invention in an expanded state;

fig. 3 is a schematic structural view of the distractible intervertebral cage in a left-side distracted and right-side distracted state, wherein (a) is a rear view and (b) is a rear sectional view;

fig. 4 is a schematic structural view of the right side of the distractible intervertebral cage in an distracted and left side in an unfolded state, wherein (a) is a rear view and (b) is a rear sectional view;

FIG. 5 is a schematic structural view of the distractible intervertebral cage of the present invention in a parallel distracted state from the left and right sides;

FIG. 6 is a schematic view of the internal structure of the distracting intervertebral cage of the present invention;

FIG. 7 is a schematic structural view of a cage body of the distractor intervertebral cage of the present invention;

FIG. 8 is a schematic structural view of a distractor of the distractible intervertebral cage of the present invention;

FIG. 9 is a schematic view of the drive shaft of the distractible intervertebral cage of the present invention;

FIG. 10 is a schematic structural view of a push block of the distractible intervertebral cage of the present invention;

FIG. 11 is a schematic view of a linkage of the distractible intersomatic cage of the present invention;

FIG. 12 is a schematic structural view of a fixing block of the distracting intervertebral cage of the present invention;

fig. 13 is a schematic structural view of a rotating rod in the distractible intervertebral cage of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

The invention provides a distractable intervertebral fusion cage, as shown in fig. 1-13, which comprises a fusion cage main body frame 1, distracting bodies 2 and 2 ' arranged above and/or below the fusion cage main body frame 1, wherein the distracting bodies 2 and 2 ' are provided with porous structures or convex teeth (which can increase the bone fusion effect and prevent the fusion cage from sliding and falling off), and for facilitating bone grafting, the middle parts of the distracting bodies 2 and 2 ' can be provided with bone grafting windows 25, wherein:

two sets of distraction structures are arranged in parallel at the left and the right in the fusion device main body frame 1, one set of the distraction structures is in driving connection with the left sides of the distraction bodies 2 and 2 ', the other set of the distraction structures is in driving connection with the right sides of the distraction bodies 2 and 2 ', so as to respectively adjust the distraction heights of the left sides or the right sides of the distraction bodies 2 and 2 ' through the two sets of distraction structures, at least one set of distraction structures in the distraction structures comprises driving shafts 3 and 3 ' and pushing blocks 4 and 4 ' which are sleeved on the driving shafts 3 and 3 ' and can move along the length direction of the fusion device main body frame 1 through the driving connection of the driving shafts 3 and 3 ', and connecting

rods

5, 5 ', 6 and 6 ' are arranged between the pushing blocks 4 and 4 ' and the distraction bodies 2 and 2 ', and the two ends of the connecting

rods

5, 5 ', 6 and 6 ' are respectively hinged with the pushing blocks 4 and 4 ' and the distraction bodies 2 and 2 ' (as can be understood that the hinged shafts at the upper ends and the lower ends of the connecting

rods

5, 5 ', 6 and 6 ' are respectively along the directions of the distraction bodies 2, 2 ', in which the size of the hinge hole in which the hinge shaft is located is preferably larger than the size of the hinge shaft to form a multi-degree-of-freedom hinge structure, which will be described later, so as to realize the left and right one-sided expansion of the distracting bodies 2, 2').

When the distracting intervertebral fusion cage is used, the distracting intervertebral fusion cage (simply called as the "fusion cage") is firstly in the closed state shown in fig. 1, then the holding device is used for holding and taking the fusion cage into an intervertebral space, the position of the fusion cage in the intervertebral disc is observed through imaging equipment, the driving shaft of the left side distraction structure is driven through a matched wrench, a push block on the driving shaft can move along the length direction of a main body frame of the fusion cage (namely the length direction of the driving shaft), and the push block drives a connecting rod to distract the left side of the distraction body so as to adjust the left side distraction height of the distraction body, which is referred to fig. 3; the driving shaft of the right side opening structure is driven by a matched wrench, so that the pushing block on the driving shaft can move along the length direction of the main body frame of the fusion cage, the pushing block drives the connecting rod to open the right side of the opening body so as to adjust the opening height of the right side of the opening body, and the reference is made to fig. 4; the supporting body can be parallelly propped open at the left side and the right side by simultaneously driving the two sets of driving shafts of the propping structures through a matched wrench, and refer to fig. 5. The doctor can freely adjust the strutting height and the inclination angle of the strutting intervertebral fusion cage by controlling the two sets of strutting structures, and takes out the holding device and the matched wrench in sequence after confirming that the position meets the requirement. The distractable intervertebral fusion device can be distracted left and right and in parallel, after the fusion device is implanted into an intervertebral disc and adjusted to the optimal position, a doctor can adjust the height and the angle of the fusion device according to the condition in the intervertebral disc, and can perfectly recover the height and the tension of a vertebral segment by utilizing the distraction force of an intervertebral implant to perform intervertebral correction.

In the above structure, the pushing block on the driving shaft moves along the length direction of the fusion cage main body frame (i.e. the length direction of the driving shaft), which may be implemented in such a way that the driving shaft does not move axially, and the pushing block moves axially along the driving shaft through a related matching structure with the driving shaft, such as a spiral connecting structure, so as to implement axial movement of the pushing block along the fusion cage main body frame; the driving shaft and the pushing block are axially fixed and are assembled in a circumferential rotation mode, and the driving shaft and the main body frame are matched through a related matching structure, so that the driving shaft can axially move relative to the fusion device main body frame, and the pushing block is driven to axially move relative to the fusion device main body frame.

According to the distractable intervertebral fusion cage, the two sets of distraction structures for respectively adjusting the distraction heights of the left side or the right side of the distraction body are arranged in parallel on the left and the right sides in the fusion cage main body frame, so that the distraction bodies can be distracted in parallel, the left and the right sides of the distraction bodies can be distracted respectively, scoliosis can be treated, compression is relieved, the height and the tension of a vertebral segment are restored, the physiological curvature of a spine is restored, the stability of the spine is guaranteed, the fixation performance of the fusion cage is good, the fusion performance is good, and the clinical requirements are met. The invention is suitable for the posterior spinal fusion fixation operation, in particular to the lumbar fusion fixation operation.

In the application, at least one of the strutting bodies 2 and 2 'and the connecting

rods

5 and 5', 6 and 6 ', and the pushing blocks 4 and 4' and the connecting

rods

5 and 5 ', 6 and 6' is a multi-degree-of-freedom hinge structure, the multi-degree-of-freedom hinge structure enables the connecting

rods

5 and 5 ', 6 and 6' to swing back and forth in the vertical direction relative to the fusion device main body frame 1, and the strutting bodies 2 and 2 'to swing left and right in the vertical direction relative to the pushing blocks 4 and 4'. The specific situation is as follows:

as shown in fig. 3 and 5, the multiple-degree-of-freedom hinge structure can be designed between the distractors 2, 2 ' and the connecting rods 5, 5 ', 6 ', and the multiple-degree-of-freedom hinge structure enables the connecting rods 5, 5 ', 6 ' to swing back and forth in the vertical direction relative to the distractors 2, 2 ', and enables the distractors 2, 2 ' to swing left and right in the vertical direction relative to the connecting rods 5, 5 ', 6 ' (i.e., the rotation direction M in fig. 3 (b)), so as to avoid the interference of the relative movement of the distractors and the jamming of the mechanism, and further facilitate the distracter intervertebral fusion cage to perform left and right unilateral distraction.

The multi-degree-of-freedom hinge structure can be designed between the push block and the connecting rod, the multi-degree-of-freedom hinge structure enables the connecting rod to swing back and forth relative to the push block in the vertical direction and enables the connecting rod to swing left and right relative to the push block in the vertical direction, the mechanism is prevented from being locked due to interference generated by relative movement of the connecting rod and the push block, and the intervertebral fusion device can be more conveniently unfolded to perform left and right unilateral unfolding.

In order to form a multi-degree-of-freedom hinge structure between the distraction body and the connecting rod, the invention can have the following structural forms:

the structure form I: as shown in fig. 1-2 and 5, the side of the spreading body 2, 2 'may be fixedly provided with a rotating shaft 8, 8' extending along the length direction thereof, the rotating shaft 8, 8 'may be rotatably provided with a hinge block 7, 7', the upper end of the connecting rod 5, 5 ', 6' is hinged with the hinge block 7, 7 'so as to form a multi-degree-of-freedom hinge structure between the spreading body 2, 2' and the connecting rod 5, 5 ', 6', such that the connecting rod 5, 5 ', 6' is not directly connected with the spreading body 2, 2 'through the connecting rod 5, 5', 6 ', but is indirectly connected with the spreading body 2, 2' through the hinge block 7, 7 ', when one side of the spreading body 2, 2' is spread (i.e. moves along the arrow N direction of (b) in fig. 3), the left and right sides of the spreading body 2, 2 'may be obliquely rotated around the hinge block 7, 7' (as shown by the arrow M of (b) in fig. 3), avoid the relative motion of the two to produce interference and lead to the mechanism card to die, more convenient can strut intervertebral fusion ware and strut about the unilateral.

Structural form two (not shown): the side surface of the spreading body is rotatably provided with a rotating shaft extending along the length direction of the spreading body, a hinge block is fixedly arranged on the rotating shaft, and the upper end of the connecting rod is hinged with the hinge block so as to form a multi-degree-of-freedom hinge structure between the spreading body and the connecting rod;

structural form three (not shown): the upper end of the connecting rod is hinged with the side surface of the opening body through a ball.

The multi-degree-of-freedom hinge between the pushing block and the connecting rod can refer to the multi-degree-of-freedom hinge between the spreading body and the connecting rod, and the details are not repeated here.

In the embodiments shown in the first and second forms of construction, as shown in fig. 5 and 8, the side of the spreading bodies 2, 2 'may be provided with recesses 21, 21' where the hinge blocks 7, 7 'are located, in order to facilitate the accommodation of the hinge blocks 7, 7'. In the embodiment shown in the figures, the opening bodies 2 and 2 'are provided with a rotating shaft channel 24 extending along the length direction of the opening bodies 2 and 2' and communicating with the grooves 21 and 21 ', and the rotating shafts 8 and 8' are inserted into the rotating shaft channel 24.

As shown in fig. 1 and 8, the grooves 21, 21 'are preferably slots penetrating in the width direction of the distractor 2, 2'. The top surfaces of the grooves 21 and 21 ' and the top surfaces of the hinged blocks 7 and 7 ' are preferably planes, a preset distance L is reserved between the top surfaces, when the single sides of the distraction bodies 2 and 2 ' are distracted to a certain degree, the top surfaces of the grooves 21 and 21 ' and the top surfaces of the hinged blocks 7 and 7 ' are contacted to limit the single sides of the distraction bodies 2 and 2 ' to be distracted continuously, and the maximum distraction angle of the single sides of the distraction bodies 2 and 2 ' can be changed by setting different preset distances L.

In the embodiment shown in fig. 1-6, the distractors include an upper distractor 2 located above the cage body frame 1 and a lower distractor 2' located below the cage body frame 1, wherein:

corresponding to the upper spreader 2, one of the two sets of the parallel-arranged spreading structures may include a first driving shaft 3 and a first pushing block 4 sleeved on the first driving shaft 3 and driven by the first driving shaft 3 to be connected and capable of moving along the length direction of the first driving shaft 3, the other set of the spreading structures includes a second driving shaft 3 ' and a second pushing block 4 ' sleeved on the second driving shaft 3 ' and driven by the second driving shaft 3 ' to be connected and capable of moving along the length direction of the second driving shaft 3 ', the connecting rod includes a hinge-joint arranged on the first pushing block 4 and one side of the upper spreader 2 (it can be understood that when the upper spreader 2 has a hinge-joint block 7, one side of the upper spreader 2 is referred to as the hinge-joint block 7, the first upper connecting rod 5 and the second upper connecting rod 6 are hinged to the hinge-joint block, when the upper spreader 2 has no hinge-joint block, one side of the upper spreader 2 is referred to as the side of the upper spreader 2, the first upper connecting rod 5 and the second upper connecting rod 6 are hinged on the side surface of the upper distraction body 2; similar descriptions below are meant and are not described in detail) and a second upper link 6 hingedly disposed between the second push block 4' and the other side of the upper distractor 2;

corresponding to the lower spreader 2 ', one of the two sets of parallel spreading structures comprises a third driving shaft and a third push block sleeved on the third driving shaft and driven by the third driving shaft to be connected and capable of moving along the length direction of the third driving shaft, the other set of parallel spreading structure comprises a fourth driving shaft and a fourth push block sleeved on the fourth driving shaft and driven by the fourth driving shaft to be connected and capable of moving along the length direction of the fourth driving shaft, and the connecting rod comprises a first lower connecting rod 5 ' hinged between the third push block and one side of the lower spreader 2 ' and a second lower connecting rod 6 ' hinged between the fourth push block and the other side of the lower spreader 2 '.

When the device is used, the first driving shaft 3 is driven by a matched wrench, the first push block 4 can move along the length direction of the first driving shaft 3, and the first push block 4 drives the first upper connecting rod 5 to open the left side of the upper opening body 2; the second driving shaft 3 'is driven by a matched wrench, so that the second pushing block 4' can move along the length direction of the second driving shaft 3 ', and the second pushing block 4' drives the second upper connecting rod 6 to prop open the right side of the upper propping body 2; the third driving shaft is driven by a matched wrench, so that the third pushing block can move along the length direction of the third driving shaft, and the third pushing block drives the first lower connecting rod 5 'to open the left side of the lower opening body 2'; the fourth driving shaft is driven by a matched wrench, so that the fourth pushing block can move along the length direction of the fourth driving shaft, and the fourth pushing block drives the second lower connecting rod 6 'to open the right side of the lower opening body 2'.

It can be conceived that if the fusion cage only needs to be propped open on the upper and lower single sides, only the upper propping body 2 or only the lower propping body 2 ' may be provided, if the upper propping body 2 ' is propped open, only the first driving shaft 3, the second driving shaft 3 ', the first pushing block 4 and the second pushing block 4 ' need to be correspondingly provided, and if the lower propping body 2 ' is propped open, only the third driving shaft, the fourth driving shaft, the third pushing block and the fourth pushing block need to be correspondingly provided.

It is also conceivable that when the upper and lower distractors 2, 2' are provided simultaneously as in the embodiment shown in fig. 1-6, the same drive shaft and the same push block can be shared by the ipsilateral distractor structure in order to reduce the volume of the entire cage, i.e.: the first driving shaft 3 and the third driving shaft are the same driving shaft, the first pushing block 4 and the third pushing block are the same pushing block, the second driving shaft 3 'and the fourth driving shaft are the same driving shaft, and the second pushing block 4' and the fourth pushing block are the same pushing block.

When the device is used, the first driving shaft 3 is driven by a matched wrench, the first pushing block 4 can move along the length direction of the first driving shaft 3, and the first pushing block 4 simultaneously drives the first upper connecting rod 5 and the first lower connecting rod 5 'to respectively open the left sides of the upper spreading body 2 and the lower spreading body 2', as shown in fig. 3; the second driving shaft 3 'is driven by a matched wrench, so that the second pushing block 4' can move along the length direction of the second driving shaft 3 ', and the second pushing block 4' simultaneously drives the second upper connecting rod 6 and the second lower connecting rod 6 'to respectively open the right sides of the upper spreading body 2 and the lower spreading body 2', as shown in fig. 4; the upper and lower distractors 2 and 2 'can be distracted in parallel by simultaneously driving the first and second drive shafts 3 and 3' with a mating wrench, as shown in fig. 5.

In the embodiment shown in the figures, various structures which can be easily conceived by those skilled in the art can be adopted to facilitate the driving of the push block to move back and forth by the driving shaft. However, in order to accurately adjust the forward and backward movement distance of the push block, the following structural form is preferably adopted in the invention:

as shown in fig. 6-7 and 9, the rear portion of the fusion cage body frame 1 is provided with a pair of driving shaft rear mounting holes 11, 11 '(i.e., threaded holes) for respectively and threadedly connecting the rear ends of the first driving shaft 3 and the second driving shaft 3', the front portion of the fusion cage body frame 1 is provided with a pair of driving shaft front mounting holes 12, 12 '(i.e., smooth holes) for respectively and slidably connecting the front ends of the first driving shaft 3 and the second driving shaft 3', each driving shaft (i.e., the first driving shaft 3 and the second driving shaft 3 ') is fixedly provided with a push block step 31, 31', and the push block 4, 4 'on each driving shaft is positioned in front of or behind the push block step 31, 31'. In the embodiment shown in the figures, the push blocks 4, 4 ' are located in front of the push block steps 31, 31 ', and the rear ends of the driving shafts 3, 3 ' are provided with driving portions, which may be hexagonal holes 32. At this time, a matched wrench is inserted into the hexagonal hole 32 at the rear end of the driving shaft 3, 3 'to drive the driving shaft 3, 3' to rotate, the driving shaft 3, 3 'moves forward in the driving shaft rear mounting hole 11, 11' and the driving shaft front mounting hole 12, 12 ', the push block ladder 31, 31' on the driving shaft 3, 3 'pushes the push block 4, 4' to move forward, and further the distraction body 2, 2 'is distracted, and the distraction height and the inclination angle of the distractable intervertebral fusion device can be accurately adjusted by controlling the movement of the driving shaft 3, 3'.

In order to stably strut the upper and lower struts 2, 2', the number of the push blocks 4 and the number of the push block steps 31 on the first drive shaft 3 are preferably two and are respectively located at the front and the rear of the first drive shaft 3; the number of pushers 4 'and the number of pusher steps 31' on the second drive shaft 3 'are also preferably two and located respectively in front of and behind the second drive shaft 3'.

The hinge joint of the two ends of the connecting rod can be designed according to the conventional technology in the art, for example, referring to the embodiment shown in fig. 10-12, the side of the pushing block 4, 4 ' is provided with a connecting rod hinge shaft 41, the pushing block 4, 4 ' is provided with a driving shaft connecting hole 42 for the driving shaft 3, 3 ' to pass through, one end of the connecting rod 5, 5 ', 6 ' is provided with a pushing block hinge hole 51 matched with the connecting rod hinge shaft 41, the hinge block 7, 7 ' is provided with a pin shaft hinge hole 71 and a rotating hole 72 for the rotating shaft 8, 8 ' to pass through, and the other end of the connecting rod 5, 5 ', 6 ' is provided with a hinge block hinge shaft 52 matched with the pin shaft hinge hole 71.

As shown in fig. 7, the head of the cage body 1 is preferably bullet-shaped in order to facilitate the implantation of the distractible intervertebral cage. In order to facilitate the holder to hold the fusion cage, a pair of holder grooves 13 may be formed at both sides of the rear portion of the fusion cage main body frame 1.

As shown in fig. 1-2, the outer surface of the distractor 2, 2' may be provided with a slope 23 gradually decreasing from the front end to the rear end of the fusion device body frame 1, and the slope 23 may be inclined at an angle of 1-7 degrees; when the distractable intervertebral fusion device is not distracted, the front end points of the distracting bodies 2 and 2 'are preferably positioned at 1/2-1/3 of the total length of the distractable intervertebral fusion device, so that the physiological angle of the intervertebral is better met, the physiological lordosis can be ideally recovered after the distracting bodies 2 and 2' are distracted, and the physiological curvature of the spine is recovered.

In the invention, the porous structures or the convex teeth arranged on the distraction bodies 2 and 2 ' can form uneven structures on the surfaces of the distraction bodies, the pores of the porous structures and the gaps between the convex teeth can provide bone growth spaces to facilitate bone fusion, and the structures improve the roughness of the surfaces of the distraction bodies 2 and 2 ', thereby improving the friction force between the distraction bodies 2 and 2 ' and vertebrae, and preventing the fusion device from shaking and slipping.

When the porous structure is provided on the struts 2 and 2', the porosity of the porous structure is preferably 40 to 90%. The pore diameter of the porous structure is preferably 300-600 μm, which is the best effect and improves the bone fusion rate of the implant. To ensure the overall strength of the stent body 2, 2 ', the stent body 2, 2' preferably comprises a solid outer frame region and a porous structure region located within the solid outer frame region. The struts 2 and 2' are preferably manufactured by 3D printing or formed by acid washing and other processes, so that a porous structure is formed on the surfaces of the struts, and the struts are convenient to fuse with bones. The material of the struts 2, 2' is preferably titanium alloy, tantalum, niobium-zirconium alloy, or other various materials.

When the distraction body is provided with the convex teeth, the convex teeth are shown in fig. 8, in order to increase the firmness of the distracter, the outer surfaces of the distraction body 2 and the distraction body 2' can be provided with transverse anti-back teeth 22, and the transverse anti-back teeth 22 can also incline towards the rear end direction of the main body frame 1 of the fusion device, so that the fusion device can be implanted. In addition, the structure of the convex teeth can also be discontinuous single bulges which are arranged at intervals.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The utility model provides a can strut interbody fusion cage which characterized in that, includes fusion cage main part frame, the top and/or the below of fusion cage main part frame are equipped with the distraction body, be equipped with porous structure or dogtooth on the distraction body, wherein:

2. A distractible intervertebral fusion device according to claim 1 wherein at least one of the distracting body and the connecting rod, and the pushing block and the connecting rod is a multi-degree-of-freedom hinge structure, the multi-degree-of-freedom hinge structure allowing the connecting rod to swing back and forth in a vertical direction with respect to the fusion device body frame and the distracting body to swing left and right in a vertical direction with respect to the pushing block.

3. A distractible intervertebral fusion device according to claim 2, wherein a multiple degree of freedom hinge structure is provided between the distractor and the connecting rod, the multiple degree of freedom hinge structure allowing the connecting rod to swing back and forth in a vertical direction relative to the distractor and allowing the distractor to swing left and right in a vertical direction relative to the connecting rod;

4. The distractible intervertebral fusion device of claim 3, wherein a rotating shaft extending along a length direction of the distracting body is fixedly arranged on a side surface of the distracting body, a hinge block is rotatably assembled on the rotating shaft, and an upper end of the connecting rod is hinged with the hinge block, so that the multiple-degree-of-freedom hinge structure is formed between the distracting body and the connecting rod;

5. A distractible intervertebral fusion device according to claim 4 wherein the sides of the distracting body are provided with recesses at which the hinge blocks are located.

6. The distractible intervertebral fusion device of any one of claims 1-5, wherein the distracting body comprises an upper distracting body located above the main body frame of the fusion device, wherein one set of distracting structures comprises a first driving shaft and a first pushing block sleeved on the first driving shaft and driven by the first driving shaft to be connected with the first pushing block and capable of moving along the length direction of the first driving shaft, the other set of distracting structures comprises a second driving shaft and a second pushing block sleeved on the second driving shaft and driven by the second driving shaft to be connected with the second pushing block and capable of moving along the length direction of the second driving shaft, and the connecting rod comprises a first upper connecting rod hinged between the first pushing block and one side of the upper distracting body and a second upper connecting rod hinged between the second pushing block and the other side of the upper distracting body;

7. An expandable intervertebral fusion device according to claim 6 wherein the first and third drive shafts are the same drive shaft, the first and third push blocks are the same push block, the second and fourth drive shafts are the same drive shaft, and the second and fourth push blocks are the same push block.

8. The distractible intervertebral fusion device of claim 7, wherein the rear portion of the fusion device body frame is provided with a pair of rear driving shaft mounting holes in parallel for respectively connecting the rear ends of the first driving shaft and the second driving shaft in a threaded manner, the front portion of the fusion device body frame is provided with a pair of front driving shaft mounting holes in parallel for respectively connecting the front ends of the first driving shaft and the second driving shaft in a sliding manner, each driving shaft is fixedly provided with a push block step, and the push block on each driving shaft is positioned in front of or behind the push block step.

9. A distractible intervertebral fusion device according to claim 8 wherein the number of push blocks and push block steps on the first drive shaft are two and located respectively at the front and rear of the first drive shaft;

10. The distractible intersomatic cage of claim 9, wherein the anterior point of the distractor is located 1/2-1/3 of the overall length of the distractible intersomatic cage when the distractible intersomatic cage is not distracted;

and/or the outer surface of the distraction body is provided with an inclined plane which gradually decreases from the front end to the rear end of the fusion cage main body frame, and the inclination angle of the inclined plane is 1-7 degrees.

11. The distractible intervertebral fusion device of claim 10 wherein the distractor comprises a solid outer frame region and a porous structural region within the solid outer frame region.