CN115381606B - An intervertebral fusion cage capable of being expanded at an angle and a spinal implant system thereof - Google Patents

Abstract

The present invention discloses an angle-expandable intervertebral fusion device and a spinal implant system, the fusion device comprises: a main body; an upper support plate, arranged at the upper part of the main body and rotatably connected to the main body; a lower support plate, arranged at the lower part of the main body and rotatably connected to the main body; an expansion push block, located between the upper support plate and the lower support plate, and the expansion push block is located in the main body; a screw, one end of the screw is threadedly connected to the expansion push block, and the other end is located at the distal end of the main body; a screw locking piece, arranged at the distal end of the main body, the material of the screw locking piece is an elastic material, and the cross-section of the part where the screw and the screw locking piece cooperate is a polygon, which is used to limit the self-rotation of the screw; an external tool rotates the screw, so that the expansion push block moves toward the distal end or toward the proximal end in the main body, so as to increase or decrease the angle of the upper support plate and the lower support plate. The fusion device of the present invention is provided with a screw locking piece to ensure that when no external force acts on the screw, the screw does not rotate by itself, and the expansion angle of the fusion device remains unchanged.

Description

Angle-expandable interbody fusion cage and spine implantation system thereof

Technical Field

The invention belongs to the field of spinal implants, and particularly relates to an intervertebral fusion device with an angle capable of being opened.

Background

Spinal fusion is a basic technique for treating spinal diseases, for establishing and maintaining spinal stability, interbody fusion is an ideal surgical form of spinal biomechanics in spinal fusion, and fusion cage is a common instrument for interbody fusion.

With the development of minimally invasive surgery technology, the conventional interbody fusion cage cannot meet the requirements of minimally invasive surgery, a working channel is established through a minimally invasive access, and under the condition that the damage to tissue around the surgery is reduced as much as possible, the fusion rate which is not lower than that of open surgery is a precondition of minimally invasive interbody fusion. In order to solve the problem that the traditional fusion device is oversized and can not be used for lumbar interbody fusion through a minimally invasive channel, the novel interbody fusion device is small in size during implantation and is in a contracted state, and the angle of an intervertebral space can be restored after being expanded, so that the physiological curve of the spinal column is restored.

However, after the fusion cage is implanted between lumbar vertebrae, after the patient resumes normal movement, the implant will experience forces and strains that will cause the screw to withdraw, resulting in a smaller fusion cage contraction and distraction angle.

Disclosure of Invention

According to the invention, the screw locking piece is integrated with the intervertebral fusion device, and the screw locking piece is further arranged under the condition that the screw thread has self-locking capability, so that the screw cannot automatically rotate when no external force acts on the screw, and the expansion angle of the fusion device is unchanged.

In order to achieve the above purpose, the technical scheme of the invention is as follows:

an angularly distractable interbody fusion cage, comprising:

The main body comprises a proximal end and a distal end, wherein the proximal end of the main body is one end close to an operator, and the distal end is one end far away from the operator;

an upper support plate provided at an upper portion of the main body and rotatably coupled to the main body;

The lower support plate is arranged at the lower part of the main body and is rotatably connected with the main body;

The expanding pushing block is positioned between the upper supporting plate and the lower supporting plate, is positioned in the main body and can move in the main body;

one end of the screw is in threaded connection with the supporting pushing block, and the other end of the screw is positioned at the far end of the main body;

the screw locking piece is arranged at the far end of the main body, the screw locking piece is matched and assembled with the screw, the cross section of the part where the screw is matched with the screw locking piece is polygonal, the part where the screw locking piece is matched with the screw is elastically deformed and used for limiting the screw to self-rotate, and only the force applied to the screw by a surgeon during implantation is increased enough to rotate the screw;

the external tool rotates the screw rod, so that the expanding pushing block moves towards the far end or the near end in the main body, the angle of the upper supporting plate and the angle of the lower supporting plate are increased or decreased, and the expanding pushing block expands away from the main body or folds towards the main body.

The bottom of the contact part of the screw locking piece and the screw is a limiting arc surface used for supporting the screw.

The screw locking piece with the both sides of screw rod contact position, keep away from the side of screw rod sets up first recess respectively, when the screw rod rotated, first recess provided the space that the screw rod locking piece was sprung.

The screw locking piece is provided with a second groove at two ends of the limiting arc surface, and when the screw rotates, two sides of the screw locking piece are more easily sprung.

The distal end of the main body is provided with a clamping groove, and the screw locking piece is inserted into the clamping groove.

The upper part of the contact part of the screw locking piece and the screw extends away from the screw, a first step is arranged at the end part of the extension, a second step is arranged in the clamping groove correspondingly, and the first step is clamped on the second step to prevent the screw locking piece from falling off from the clamping groove.

The stretching pushing block comprises a pushing block body, and inclined planes stretching the upper supporting plate and the lower supporting plate are arranged on the upper surface and the lower surface of the pushing block body.

Because the upper support plate and the lower support plate are rotatably connected with the main body, the upper support plate and the lower support plate are easy to rotate relative to the main body, a wedge surface for preventing the upper support plate and the lower support plate from rotating is arranged on the push block body, the two sides of the push block body extend towards the proximal end of the main body, a wedge surface is arranged at the end part of the extension, correspondingly, a flange is arranged at the matched part of the upper support plate and the lower support plate and the wedge surface, and the wedge surface is matched with the flange to prevent the upper support plate and the lower support plate from rotating relative to the main body.

The upper support plate and the lower support plate are rotatably connected with the main body through pin shafts.

One end of the pin shaft is provided with a riveting edge, and after the pin shaft is installed, the riveting edge is turned outwards to prevent the pin shaft from falling off.

The upper support plate and the lower support plate are respectively provided with an arc surface matched with the inclined surface, so that the upper support plate and the lower support plate can conveniently move along the inclined surface of the push block body.

The distal ends of the upper and lower support plates are wedge-shaped, with the distal ends of the upper and lower support plates being initially inserted into the disc space, and the ends being designed to be wedge-shaped so that the cage is more easily inserted into the disc space of a patient with disc disease while minimizing damage to surrounding anatomy.

The bone contact surfaces of the upper support plate and the lower support plate are provided with anti-motion grooves which can be in tooth shapes and prevent the fusion cage from sliding after being implanted into the intervertebral space.

The upper support plate, the lower support plate and the main body contact surface are provided with reinforcing ribs, so that the compressive strength of the support plate is enhanced.

The distal end of the body is bullet-shaped and is also first inserted into the disc space, and the end is designed to be bullet-shaped so that the cage is easier to insert into the disc space of a patient with disc disease while minimizing damage to surrounding anatomy.

The proximal end of the body is provided with a clamping groove for clamping an external instrument.

The upper and lower surfaces of the proximal end of the main body are respectively provided with a supporting surface which is contacted with the adjacent vertebral bodies and is also used for supporting the upper supporting plate and the lower supporting plate, and the supporting surfaces are preferably inclined surfaces which form 5-10 degrees with the horizontal surfaces.

The spreadable angle of the fusion device is 0-20 degrees, and the fusion device is spread to 20 degrees of oblique anterior convexity or anterior convexity according to clinical requirements of patients.

The invention also provides an angle-expandable intervertebral fusion device suitable for the TLIF operation mode, which comprises the angle-expandable intervertebral fusion device, and because the upper support plate and the lower support plate are rotationally connected with the main body around the pin shaft, the central line of the pin shaft is kept parallel to the coronal plane of the vertebral body, the upper support plate and the lower support plate are ensured to be adhered to the adjacent vertebral body, the proximal end face of the fusion device is inclined with the pin shaft, the push block body and the main body, and the proximal end face of the fusion device is parallel to the axis of the pin shaft.

The angle formed by the proximal end face of the fusion device and the proximal side face is 50-60 degrees.

By adopting the technical scheme, the invention has the following advantages and positive effects compared with the prior art:

The intervertebral fusion device is provided with the screw rod and the screw rod locking piece, the screw rod is in threaded connection with the supporting pushing block, the screw rod locking piece is matched with the screw rod at the far end of the main body under the condition that the screw thread has self-locking capability, and the cross section of the matched position of the screw rod is polygonal, so that the screw rod can be rotated only when the force applied to the screw rod by a surgeon is increased enough to overcome the edges of the polygonal surface in the implantation process, the upper supporting plate and the lower supporting plate of the fusion device can be contracted or expanded, and the screw rod can not be rotated when no external force acts. Therefore, the screw locking piece ensures that the screw cannot rotate by itself when no external force acts on the screw, so that the normal movement of a patient can not cause the invariable opening angle after the fusion device is implanted into the patient, and the service life of the fusion device in the patient is prolonged.

The fusion cage can be gradually expanded to 20 degrees of oblique anterior convexity or anterior convexity angle according to the needs of patients, a surgeon does not need to test a mould to repeatedly insert into an intervertebral space, damage of surrounding anatomical structures is reduced, operation time is shortened, the distance between adjacent vertebral bodies is not required to be expanded, and the problems of postoperative lumbar muscle pain, dysfunction and the like caused by excessive traction of muscles, nerves and dura mater sacs in operation when the traditional fusion cage is implanted are solved.

Drawings

Fig. 1 is a schematic perspective view of a fusion device according to embodiment 1 of the present invention;

FIG. 2 is a top view of the cage of example 1 of the present invention;

FIG. 3 is a front view of the cage of embodiment 1 of the present invention;

FIG. 4 is an exploded view of the cage of example 1 of the present invention;

fig. 5a is a first structural view of the main body of the cage of embodiment 1 of the present invention;

fig. 5b is a second structural view of the main body of the cage of embodiment 1 of the present invention;

FIG. 6a is a first block diagram of the upper support plate of the cage of embodiment 1 of the present invention;

FIG. 6b is a second block diagram of the upper support plate of the cage of embodiment 1 of the present invention;

Fig. 7 is a structural diagram of an expanding push block of the fusion cage of embodiment 1 of the present invention;

FIG. 8 is a block diagram of the screw of the cage of example 1 of the present invention;

FIG. 9 is a block diagram of the screw lock of the cage of example 1 of the present invention;

fig. 10 is a structural view of a pin shaft of the cage of embodiment 1 of the present invention;

FIG. 11 is a block diagram showing the cooperation of the cage body and the spreader pushing block according to embodiment 1 of the present invention;

FIG. 12 is a block diagram of section A-A of FIG. 2;

FIG. 13 is a block diagram of section B-B of FIG. 3;

fig. 14 is a schematic perspective view of a fusion device according to embodiment 2 of the present invention;

FIG. 15 is a schematic view of the main structure of the fusion device according to embodiment 2 of the present invention;

fig. 16 is a schematic structural view of an expanding push block of the fusion device according to embodiment 2 of the present invention;

fig. 17 is a schematic structural diagram of the main body of the cage adapted to TLIF and the push block according to the embodiment of the present invention.

The reference numerals illustrate 1-body, 101-bearing surface, 102-screw hole, 103-clamping groove, 1031-second step, 104-third step, 105-tool clamping groove, 106-insert tool hole, 107-horizontal plane or near horizontal plane, 108-near end surface, 109-near end side, 1010-circular arc shape, 1011-bullet-shaped, 2-upper support plate, 201-bone contact surface, 202-body contact surface, 203-anti-moving groove, 204-insert tool groove, 205-circular arc surface, 206-flange, 207-reinforcing rib, 208-wedge shape, 3-lower support plate, 4-expanding push block, 401-push block body, 402-inclined plane, 403-wedge surface, 404-threaded hole, 5-screw, 501-threaded, 502-socket, 503-polygonal shape, 6-screw locking piece, 601-limiting arc surface, 602-first groove, 603-second groove, 604-first step, 7-pin shaft, 701-fourth step, 702-flange, 8-pin hole, 801-fifth step, and 9-hollowed-out middle part.

Detailed Description

The invention provides an angle-expandable interbody fusion cage which is further described in detail below with reference to the accompanying drawings and specific examples. The advantages and features of the present invention will become more apparent from the following description.

The term "proximal" is the end closer to the operator and "distal" is the end farther from the operator.

Example 1

Referring to fig. 1-13, the angle-expandable interbody fusion cage comprises a main body 1, an upper supporting plate 2, a lower supporting plate 3, an expanding pushing block 4, a screw 5 and a screw locking piece 6, wherein the expanding pushing block 4 is positioned between the upper supporting plate 2 and the lower supporting plate 3 and positioned in the main body 1, the upper supporting plate 2 and the lower supporting plate 3 are respectively and rotatably connected with the main body 1, the expanding pushing block 4 can move in the main body 1, and the proximal end of the screw 5 is in threaded connection with the expanding pushing block 4. The external tool acts on the proximal end of the screw rod 5, the screw rod 5 rotates, so that the expanding pushing block 4 moves towards the distal end or towards the proximal end in the main body 1, the angle of the upper supporting plate 2 and the lower supporting plate 3 is increased or decreased, and the upper supporting plate 2 and the lower supporting plate 3 are expanded away from the main body 1 or folded towards the main body 1. The fusion cage is implanted in the lumbar intervertebral space in the closed state, and an external tool acts on the screw 5 to push the upper support plate 2 and the lower support plate 3 until the intervertebral space is at a proper angle, so that the fusion cage can be implanted without firstly expanding the adjacent vertebral bodies by an excessive space and without repeatedly testing the mould to insert the intervertebral space. The cage is implanted into the intervertebral space, adjusted to a desired intervertebral space angle, and the distal height of the cage is greater than the proximal height of the cage, thereby restoring the more natural lordotic curvature of the particular segment of the lumbar spine.

As shown in fig. 5a and 5b, the main body 1 is designed with a hollow-out portion 9, and is used for placing the expanding pushing block 4, the screw 5 and the like, and is also used for implanting bone filler and fusion of a vertebral body, wherein the bone filler can be a common bone filler material such as autologous bone, allogeneic bone, artificial bone and the like. The hollow 9 in the middle of the main body 1 can be rectangular or square, and the main body 1 can be other shapes besides rectangular or square. The upper and lower surfaces of the proximal end of the main body 1 are provided with supporting surfaces 101 contacting the adjacent vertebral bodies, the supporting surfaces 101 support the proximal ends of the upper and lower supporting plates 2 and 3, and the supporting surfaces 101 are preferably inclined surfaces having an angle of 5-10 degrees from the horizontal surface and inclined from the proximal direction.

The distal end of the body 1 is designed in a bullet shape 1011 to facilitate insertion of the cage into the collapsed disc space of a patient suffering from degenerative disc disease while minimizing damage to surrounding anatomy. The distal end of the main body 1 is provided with a clamping groove 103, and the screw locking member 6 is embedded in the clamping groove 103 to be matched with the screw 5, so that the main body 1 is provided with a screw hole 102, and the end part of the screw 5 passes through the screw hole 102 to be matched with the screw locking member 6. The upper and lower surfaces of the proximal end of the main body 1 are respectively provided with a supporting surface 101, the upper and lower surfaces close to the distal end of the main body 1 are horizontal surfaces or nearly horizontal surfaces 107, the horizontal surfaces or nearly horizontal surfaces 107 are connected with the supporting surface 101 through a third step 104, and when the fusion device is in a folded state, the upper supporting plate 2 and the lower supporting plate 3 of the fusion device are arranged in parallel. External tool instrument holding grooves 105 are formed on both sides of the proximal end of the main body 1, and external tools are held in the instrument holding grooves 105 to implant the fusion cage into the collapsed intervertebral disc space of the patient. An insertion tool hole 106 is provided in the center of the proximal end surface of the body 1, and an insertion tool is passed through the insertion tool hole 106 to be applied to the screw 5, which hole is also used for injection of bone filler.

Referring to fig. 6a and 6b, the fusion device further comprises an upper support plate 2 and a lower support plate 3, wherein the upper support cross plate and the lower support plate 3 are arranged in a mirror image manner (the upper support plate and the lower support plate have the same structure, and the description of the upper support plate and the lower support plate is given by way of example above the support plate), and are respectively and rotatably connected with the main body 1, and can be rotatably connected with the main body 1 through a pin shaft 7. The pin shaft 7 passes through pin holes 8 formed in the upper support plate 2, the lower support plate 3 and the main body 1, so that the upper support plate 2 and the lower support plate 3 are rotatably connected to the main body 1, the upper support plate 2 and the lower support plate 3 can rotate relative to the main body 1 by pushing the push block 4, the pin holes 8 are positioned near the proximal end of the fusion cage, and after the upper support plate 2 and the lower support plate 3 rotate in a direction away from the main body 1, the vertical distance between the upper support plate 3 and the lower support plate 3 at the distal end of the fusion cage is increased, thereby restoring the more natural lordosis curvature of a specific section of lumbar vertebra. The upper support plate 2 and the lower support plate 3 are also designed with hollow parts 9 in the middle for implanting bone filler to be fused with adjacent vertebral bodies as soon as possible. The distal ends of the upper buttress plate 2 and the lower buttress plate 3 are each designed to have a wedge-like shape 208 to facilitate insertion of the cage into the collapsed disc space of a patient with degenerative disc disease while minimizing damage to surrounding anatomy. The upper buttress plate 2 and the lower buttress plate 3 have bone contacting surfaces 201, the bone contacting surfaces 201 contacting the vertebral bodies adjacent the disc space in which the cage is inserted. The bone contacting surface 201 has an anti-motion groove 203 thereon, the anti-motion groove 203 preventing the cage from sliding after implantation in the patient's intervertebral space. The anti-static grooves 203 may be in the form of teeth as shown, or may be otherwise treated (e.g., by a sand blasting process, etc.) to create a roughened or uneven surface on the bone contacting surface 201 to promote bone growth.

The upper support plate 2 and the lower support plate 3 are provided with main body contact surfaces 202, and the main body contact surfaces 202 are provided with reinforcing ribs 207, so that after the fusion cage is implanted into the intervertebral disc space, the compressive strength of adjacent vertebral bodies to the upper support plate 2 and the lower support plate 3 is enhanced. The proximal end surfaces of the upper support plate 2 and the lower support plate 3 are respectively provided with an embedding tool groove 204.

Referring to fig. 7, the fusion device further comprises a supporting pushing block 4 arranged between the upper supporting plate 2 and the lower supporting plate 3 and hollow in the middle of the main body 1, the screw 5 penetrates through the supporting pushing block 4 and is in threaded connection with the supporting pushing block 4, when the screw 5 rotates, the supporting pushing block 4 moves towards the proximal end of the main body 1 or moves towards the distal end of the main body 1, the supporting pushing block 4 comprises a pushing block body 401, inclined planes 402 supporting the upper supporting plate 2 and the lower supporting plate 3 are arranged on the upper surface and the lower surface of the pushing block body 401, the supporting pushing block 4 moves, and the inclined planes 402 on the moving pushing block body 401 support the upper supporting plate 2 and the lower supporting plate 3 or shrink the upper supporting plate 2 and the lower supporting plate 3, so that the supporting angle between the upper supporting plate 2 and the lower supporting plate 3 is increased or decreased. In order to reduce friction resistance at the position where the upper support plate 2 and the lower support plate 3 are matched with the inclined surface 402 when the push block body 401 moves, the position where the upper support plate 2 and the lower support plate 3 are matched with the inclined surface 402 is designed to be an arc surface 205.

Since the upper support plate 2 and the lower support plate 3 are rotatably connected with the main body 1, the upper support plate 2 and the lower support plate 3 may rotate themselves, so that the push block body 401 is provided with a wedge surface 403 for preventing the upper support plate 3 and the lower support plate 3 from rotating, two sides of the push block body 401 extend towards the proximal end of the main body 1, the extended end is provided with the wedge surface 403, correspondingly, the parts of the upper support plate 2 and the lower support plate 3, which are matched with the wedge surface 403, are provided with flanges 206, and the wedge surface 403 is matched with the flanges 206 to prevent the upper support plate 2 and the lower support plate 3 from rotating relative to the main body 1.

Referring to fig. 8, the fusion device further comprises a screw 5, and the screw 5 is driven to rotate so as to enable the expanding pushing block 4 to move. The screw 5 is threaded 501 on the outer surface of the part near the proximal end, the screw 5 passes through the expanding push block 4, the threaded part of the screw is connected with the threads 501 of the expanding push block 4, therefore, the threaded hole 404 matched with the threaded part on the screw is arranged on the push block body 401, the distal end of the screw 5 passes through the threaded hole 404 of the push block body 401 and abuts against the screw hole 102 of the main body 1, the proximal end of the screw 5 is provided with a socket 502 or other mechanism (such as a slotted or cross screwdriver bit structure or a plum blossom screwdriver hole) which can be connected to an embedding tool, and the embedding tool drives the screw 5 to rotate.

After the fusion cage is implanted between lumbar vertebrae, the patient resumes normal movement, and the implant will experience a force and strain that will withdraw the screw 5, resulting in a smaller fusion cage contraction and distraction angle. Therefore, in order to prevent the rotation of the screw 5 from causing the opening angle of the fusion device to be reduced, the screw 5 adopts a thread 501 with a self-locking function, but in order to further prevent the rotation of the screw 5, referring to fig. 9 and 11-13, the fusion device further comprises a screw locking piece 6, the screw locking piece 6 is clamped in a clamping groove 103 at the far end of the body, the cross section of the part matched with the thread 501 of the screw 5 and the far end of the screw 5 is a polygon 503, the part matched with the screw 5 and the screw locking piece 6 is used for limiting the self-rotation of the screw 5, the part contacted with the screw 5 is provided with a certain elastic deformation, when the screw 5 rotates, the screw locking piece 6 meets the edge of the polygon 503, the edge can spring the screw locking piece 6, then the screw locking piece returns to the original shape, and when the screw rotates to the polygon surface meets the screw locking piece, the screw locking piece is sprung off and then returns to the original shape, and the screw 5 can rotate only when the force applied to the polygon 503 of the screw 5 by a surgeon in the implantation process is increased enough to overcome the edge of the polygon 503 of the screw 5, so that the self-locking function of the screw locking piece is realized.

Referring to fig. 9, 11-13, the bottom of the contact part of the screw locking piece 6 and the screw 5 is a limiting arc-shaped surface 601, the limiting arc-shaped surface 601 also has the function of supporting the screw 5, the two sides of the contact part of the screw locking piece 6 and the screw 5 are respectively provided with a first groove 602, the sides far away from the screw 5 are respectively provided with a first groove 602, and when the screw 5 rotates, the first grooves 602 provide a space for the screw locking piece 6 to spring open. On the screw locking piece 6, and the two ends of the limiting arc-shaped surface 601 are provided with second grooves 603, when the screw 5 rotates, the two sides of the screw locking piece 6 can be sprung out more easily. Because the screw locking piece 6 is clamped in the clamping groove 103, in order to prevent the screw locking piece 6 from falling off from the clamping groove 103, the upper part of the contact part of the screw locking piece 6 and the screw 5 extends in the direction away from the screw 5, and the extending end part is provided with the first step 604, correspondingly, the clamping groove 103 is provided with the second step 1031, and the first step 604 is clamped on the second step 1031 to prevent the screw locking piece 6 from falling off from the clamping groove 103.

Referring to fig. 10, the upper support plate 2 and the lower support plate 3 are rotatably connected with the main body 1 through a pin shaft 7, a fourth step 701 is provided at one end of the pin shaft 7, and correspondingly, a fifth step 801 is also provided at the end of the pin hole 8, and the fourth step 701 is embedded in the fifth step 801 to prevent the pin shaft 7 from falling off from the pin hole 8. In order to further prevent the pin shaft 7 from falling off, a riveting edge 702 is arranged at the other end of the pin shaft 7, and after the pin shaft 7 is installed, the riveting edge 702 is extruded by a conical punch, so that the riveting edge 702 is turned outwards, and the self-locking effect is achieved.

The angle of the invention can be expanded from 0 to 20 degrees, and the angle can be gradually expanded to 20 degrees of oblique anterior convexity or anterior convexity according to clinical requirements of patients, thus being applicable to lumbar fusion operation.

As shown in fig. 1-13, the fusion device of the present embodiment may be used in a surgical manner such as PLIF, TLIF, etc., and may be used as an open surgery or a minimally invasive surgery, PLIF is a posterior interbody fusion, and TLIF is a trans-vertebral approach interbody fusion.

Example 2

This embodiment provides another configuration of the cage, which is primarily suitable for use in interbody fusion procedures (TLIF). The construction of the cage according to fig. 14-17 is similar to that of the cage according to embodiment 1, because TLIF is an interbody fusion procedure via the foramen, the rotation axis of the upper support plate 2 and the lower support plate 3, i.e. the axis of the pin shaft 7, is designed to be parallel to the axis of the coronal plane of the vertebral body, while in order to ensure that the upper support plate 2 and the lower support plate 3 are attached to the adjacent vertebral body, the pins 7 of the main body 1 and the pusher body 401 are both designed to be inclined, as shown in fig. 15, the center line of the pin shaft 7 is parallel to the proximal end surface 108 of the main body, and the proximal end surface of the cage, i.e. the proximal end surface 108 of the main body 1 and the proximal side surface 109, have an included angle of 50-60 degrees, and the distal end of the main body 1 is designed to be circular arc 1010, which is matched with the annulus fibrosus of the vertebral body, thereby increasing the contact area. As shown in fig. 16, the spreader 4 is inclined with respect to the spreader 4 of embodiment 1, and since the whole fusion device is inclined, the spreader 4 has a wedge surface 403 on only one side to engage with the upper support plate 2 and the lower support plate 3, thereby preventing the rotation of the upper support plate 2 and the lower support plate 3. The supporting principle of the upper supporting plate 2 and the lower supporting plate 3 is the same as PLIF.

The interbody fusion cage can enable a surgeon to prop open gradually to 20 degrees of oblique anterior convexity or anterior convexity angle according to clinical requirements of patients, so that the surgeon can determine the fusion cage with proper height without expanding the adjacent vertebral bodies by too high distance before repeating the operation of inserting the test mould into the intervertebral space. Therefore, the intervertebral fusion device reduces the problems of postoperative lumbar muscle pain, dysfunction and the like caused by excessive traction of muscles, nerves and dura mater sacs in operation when the traditional fusion device is implanted, reduces the damage of surrounding planing structures, and shortens the operation time. Particularly, the invention also integrates a self-locking function, the screw 5 self-locking piece prevents the screw 5 from rotating, the opening angle of the fusion device is prevented from changing after the fusion device is implanted into the intervertebral space of a patient, the wedge-shaped surface 403 of the opening pushing block 4 is matched with the flanges 206 of the upper support plate 2 and the lower support plate 3 to prevent the upper support plate 2 and the lower support plate 3 from rotating around the pin shaft 7, and the riveting edge of the pin shaft 7 is arranged, so that the self-locking function of the pin shaft 7 is achieved, and the reliability of the pin shaft 7 is improved.

Example 3

A spinal implant system comprising the angularly distractable interbody fusion cage of embodiment 1 or embodiment 2.

The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is within the scope of the appended claims and their equivalents to fall within the scope of the invention.

Claims (17)

1. An angularly distractable interbody fusion cage, comprising:

a main body;

An upper support plate provided at an upper portion of the main body, a proximal end of the upper support plate being rotatably connected to a proximal end of the main body;

The lower support plate is arranged at the lower part of the main body, and the proximal end of the lower support plate is rotatably connected with the proximal end of the main body;

the expanding push block is positioned between the upper supporting plate and the lower supporting plate, is positioned in the main body and can move in the main body, and comprises a push block body, and inclined planes for expanding the upper supporting plate and the lower supporting plate are arranged on the upper surface and the lower surface of the push block body;

one end of the screw is in threaded connection with the supporting pushing block, and the other end of the screw is positioned at the far end of the main body;

the screw locking piece is arranged at the far end of the main body, the screw locking piece is matched and assembled with the screw, the cross section of the part of the screw matched with the screw locking piece is polygonal, and the part of the screw locking piece matched with the screw is elastically deformed;

The external tool rotates the screw rod to enable the expanding pushing block to move towards the distal end or move towards the proximal end in the main body, so that the angle of the distal ends of the upper supporting plate and the lower supporting plate is increased or decreased;

The screw locking piece is characterized in that the bottom of the contact part of the screw locking piece and the screw is a limiting arc surface, first grooves are respectively formed in the two sides of the contact part of the screw locking piece and the screw, the sides of the contact part of the screw, which are far away from the screw, are provided with space for the screw locking piece to spring open when the screw rotates, and second grooves are formed in the two end parts of the limiting arc surface on the screw locking piece.

2. The angularly distractable interbody fusion cage of claim 1, wherein the distal end of the body is provided with a slot into which the screw lock is inserted.

3. The angle distractable interbody fusion cage according to claim 2, wherein an upper portion of a contact portion of the screw locking member with the screw extends in a direction away from the screw, and the extended end portion is provided with a first step, and correspondingly, the clamping groove is provided with a second step, and the first step is clamped on the second step to prevent the screw locking member from falling off from the clamping groove.

4. The distractable intervertebral fusion of claim 1 wherein the pusher body extends proximally from the body at both sides thereof and a wedge surface is provided at the end of the extension and, correspondingly, the upper and lower support plates are provided with flanges at the location where the wedge surfaces mate, the wedge surface mates with the flanges to prevent self-rotation of the upper and lower support plates relative to the body.

5. The angle distractable interbody fusion cage of claim 1, wherein the upper and lower support plates are rotatably connected to the body by pins.

6. The angle distractable interbody fusion cage of claim 5, wherein one end of the pin is provided with a riveted edge, and the pin is mounted with the riveted edge turned outward to prevent the pin from falling off.

7. The angle distractable intervertebral fusion device of claim 1 wherein the upper support plate and the lower support plate are each provided with an arcuate surface that mates with the beveled surface.

8. The angularly distractable interbody fusion cage of claim 1 or 7, wherein the distal ends of the upper and lower support plates are each wedge-shaped.

9. The angularly distractable intervertebral fusion of claims 1 or 7 wherein bone contacting surfaces of the upper and lower plates are each provided with an anti-motion slot preventing sliding of the fusion after implantation in the intervertebral space.

10. The angle distractable intervertebral fusion of claim 1 or 7, wherein the upper and lower support plates are provided with ribs on the contact surface with the body.

11. The angle distractable intervertebral fusion of claim 1 wherein the proximal end of the body is provided with a clamping groove for external instrument clamping.

12. The distractable intervertebral fusion of claim 1 wherein upper and lower surfaces of the proximal end of the body are each provided with a bearing surface for contacting a vertebral body.

13. The distractable intervertebral fusion of claim 12 wherein the bearing surface is an inclined surface at an angle of 5 ° -10 ° to the horizontal.

14. The angularly distractable intervertebral fusion of claim 1 wherein the distractable cage is at an angle of 0 ° -20 °.

15. An angularly distractable intervertebral fusion device comprising the angularly distractable intervertebral fusion device of any one of claims 1-14;

The proximal end face of the fusion device and the pin shaft are inclined, and the proximal end face of the fusion device is parallel to the axis of the pin shaft.

16. The angle distractable intervertebral fusion of claim 15 wherein the fusion proximal end face and the proximal side face form an angle of 50 ° to 60 °.

17. A spinal implant system comprising an angularly distractable intervertebral fusion of any one of claims 1-15 or an angularly distractable intervertebral fusion of any one of claims 15-16.