Artificial intervertebral disc with springback function

Abstract

The utility model relates to the technical field of artificial intervertebral discs, in particular to an artificial intervertebral disc with a springback function, which comprises an artificial intervertebral disc body, and the artificial intervertebral disc body is of an integrally formed structure or a split structure. The artificial intervertebral disc body comprises an upper fixing plate, a lower fixing plate and an elastic body arranged between the upper fixing plate and the lower fixing plate; the outer surfaces of the upper fixing plate and the lower fixing plate are respectively provided with micropores and biological coatings for bone ingrowth induced by hydroxyapatite, and the upper fixing plate and the lower fixing plate are respectively provided with a plurality of round holes and fixing teeth. The intervertebral plate is reasonable in structural design, can perform multiple fixation on the vertebral body, can perform good axial compression and rebounding in the longitudinal axis direction of the vertebral column of the human body, can perform flexion and extension, lateral bending, rotation and other motions, can reconstruct dynamic stability of an intervertebral long segment after the intervertebral plate and the vertebral body are cut off, and is high in physiological activity matching degree with the normal vertebral column of the human body; implantation is convenient, fixation is stable, rebound resilience is high, and elasticity is lasting.

Description

Technical Field

[0001] This utility model relates to the technical field of medical devices, and in particular to an artificial intervertebral disc with a rebound function. Background Technology

[0002] Cervical and lumbar degenerative diseases are common in spinal surgery. Fusion surgery, as the ultimate treatment, can fix the affected segment, correct spinal deformities, and restore spinal stability, achieving good clinical results. However, over time, many clinical and basic studies have found that rigid internal fixation combined with bone grafting fusion can lead to accelerated degeneration of adjacent segments. Against this backdrop, the concept of "dynamic fixation" has been proposed. This involves restoring spinal stability while preserving beneficial intersegmental movement and load transfer, without vertebral segmental fusion. This dynamic stabilization model can, to some extent, preserve the range of motion of the surgical segment and reduce the risk of accelerated degeneration of adjacent segments. Although there is currently no quantitative standard to assess the limitation of dynamic fixation on the range of motion of unstable lumbar segments, the concept and methods of dynamic fixation have been accepted by most spinal surgeons, and corresponding products are increasingly used clinically, such as artificial intervertebral discs, artificial nuclei, elastic pedicle systems, facet joint replacement systems, and interspinous dynamic fixation systems. Among these, artificial intervertebral disc replacement has the highest biomechanical compatibility with the human spine and has therefore been the subject of relatively more research.

[0003] The earliest recorded lumbar disc replacement surgery involved placing a metal ball as the lumbar disc prosthesis into the diseased intervertebral space, which ultimately failed due to prosthesis subsidence. With technological advancements, prosthesis design has evolved from initial inelastic and elastic prostheses to current articular inelastic prostheses. Current artificial disc products mostly allow for horizontal movement and rotation, but struggle to provide adequate elastic cushioning along the longitudinal axis of the spine. The inability to achieve sufficient axial compression and good rebound along the longitudinal axis of the spine is currently a bottleneck in existing artificial disc designs. Other issues, such as insufficient fixation and rapid wear, can also lead to a series of complications. Currently, an integrated elastic artificial intervertebral disc has been designed and a series of patents have been obtained. It can simulate the normal human intervertebral disc to a certain extent to adapt to the axial compression and rebound along the longitudinal axis of the spine. However, due to structural limitations, the existing artificial intervertebral discs with rebound function cannot achieve sufficient axial elastic compression and rebound along the longitudinal axis of the spine. The connection between the disc and the vertebral body is also not stable. After long-term use, it is easy to produce obvious elasticity decay and / or loosening of the prosthesis, which will affect the long-term use effect of the prosthesis.

[0004] In recent years, polyurethane artificial intervertebral discs have been designed, which possess good elasticity. However, like other polyurethane materials, medical-grade polyurethane ages over time due to environmental factors and repeated mechanical stress. This aging process can lead to a decline in material properties, such as reduced strength, decreased elasticity, and cracking. Furthermore, when one or more vertebrae are removed from the spine, the adjacent superior and inferior intervertebral discs are also removed, resulting in segmental intervertebral defects. Currently, for such long segmental intervertebral defects, interbody fusion is often performed clinically. However, there are currently no suitable artificial intervertebral disc products with good elasticity worldwide to reconstruct the dynamic stability of long segmental intervertebral defects in the spine.

[0005] Therefore, this application requires the design of an artificial intervertebral disc with good rebound function to solve the above-mentioned technical problems. Utility Model Content

[0006] To overcome the shortcomings of the existing technology, the technical problem to be solved by this utility model is to provide an artificial intervertebral disc with a rebound function. Its structure is reasonably designed, it can be fixed in multiple ways on the vertebral body, it can perform good axial compression and rebound in the longitudinal axis of the human spine, it can perform flexion, extension, lateral bending and rotation, and it can also reconstruct the dynamic stability of the long segment of the intervertebral disc after the removal of the intervertebral disc and vertebral body. It has a high degree of matching with the physiological activities of the normal human spine, is easy to implant, is firmly fixed, has strong rebound and long-lasting elasticity.

[0007] To achieve the above objectives, this utility model provides an artificial intervertebral disc with a rebound function, comprising an artificial intervertebral disc body, which is either an integrally molded structure or a split structure; the artificial intervertebral disc body includes an upper fixation plate, a lower fixation plate, and an elastomer disposed between the upper and lower fixation plates; the outer surfaces of the upper and lower fixation plates are respectively provided with micropores and a hydroxyapatite-induced bone ingrowth bio-coating, and the upper and lower fixation plates are respectively provided with multiple round holes and fixation teeth; the distance between one end port of the upper and lower fixation plates is greater than the distance between the other end ports; the elastomer is composed of one or more sets of elastic monomers.

[0008] Preferably, the upper or lower fixation plate is circular or non-circular in structure, and may or may not have an extension plate. The corner of the upper or lower fixation plate connecting to the vertebral body is planar or convex. One end of the upper or lower fixation plate at the large-spacing port may or may not have an extension plate. The extension plate has a circular screw hole with a locking thread for inserting a locking screw. One side of the circular screw hole has an anti-retraction screw to prevent the locking screw from retracting. Alternatively, the extension plate at the end of the upper or lower fixation plate has a pin hole for using a pin for auxiliary fixation during surgery. The pin has a base larger than the pin hole, and the pin hole has a stepped design to prevent the pin base from dislodging towards the vertebral body. The pin has anti-retraction teeth to prevent the pin from retracting away from the vertebral body.

[0009] Preferably, the elastomer is composed of one or two sets of elastic monomers; the upper and lower fixing plates in the gap between the two sets of elastic monomers are fixedly connected with pins or have pin holes and are equipped with movable pins; when the elastomer is composed of a set of monomers, the upper or lower fixing plates in front of and / or on the side of the elastomer are fixedly connected with pins or have pin holes and are equipped with movable pins.

[0010] Preferably, the movable pin is initially fitted into the pin holes on the upper and lower fixing plates, with the tip of the pin slightly protruding from the surface of the upper or lower fixing plate. The pin has an expansion joint in the middle, anti-retraction teeth on both sides, and a base at the bottom to prevent it from dislodging towards the vertebral body. When the pin moves from the pin hole on the upper or lower fixing plate into the vertebral body, the anti-retraction teeth on both sides can engage with the surface of the upper or lower fixing plate, preventing it from dislodging away from the vertebral body. Furthermore, the base at the bottom of the pin is larger than the pin hole, thus preventing the pin from dislodging into the vertebral body through the fixing plate.

[0011] Preferably, the set of elastic units consists of a partially open circular part connected to a connecting plate and then integrated with an upper fixed plate, with a circular base plate connected to the lower connecting plate; the set of elastic units consists of a partially open circular part connected to a connecting plate, with the upper connecting plate integrated with the upper fixed plate, and the lower connecting plate connected to the circular base plate and then in contact with the lower fixed plate through the circular base plate (split type), or the elastic unit is integrated with the upper fixed plate and the lower fixed plate through the connecting plate (integrated type).

[0012] Preferably, the set of elastic units consists of two opposing open circles connected to a connecting plate and then integrated with an upper fixing plate before contacting a lower fixing plate (split type), or a set of elastic units consists of two opposing open circles connected to a connecting plate and then integrated with an upper fixing plate and a lower fixing plate respectively (integrated type).

[0013] Preferably, the set of elastic monomers consists of three sets of opposing open circles connected to the connecting plate and then respectively connected to the upper fixing plate and the lower fixing plate to form an integral whole.

[0014] Preferably, the set of elastic units consists of a set of opposing open circles and two circles with partial openings in the same direction connected to a connecting plate, and then connected to the upper fixing plate and the lower fixing plate respectively; the set of elastic units consists of a set of opposing open circles and two circles with openings in different directions connected to a connecting plate, and then connected to the upper fixing plate and the lower fixing plate respectively; the set of elastic units consists of four partially open circles connected to each other, and then connected to the upper fixing plate and the lower fixing plate respectively; the set of elastic units consists of three circles with openings in the same direction connected to the upper fixing plate and the lower fixing plate respectively via a connecting plate; the set of elastic units consists of a set of partially open circles connected to each other via a connecting plate, plus a set of partially open circles directly connected, and then connected to the upper fixing plate and the lower fixing plate respectively.

[0015] Preferably, the outer surface of the upper or lower fixation plate is treated with pores and coated with a biological coating such as hydroxyapatite; multiple fixation teeth are evenly distributed on the upper or lower fixation plate, and the round holes on the upper or lower fixation plate facilitate bone embedding or ingrowth.

[0016] Preferably, the upper fixing plate and the lower fixing plate are integrated with the elastic body via a connecting plate, or the upper fixing plate is integrated with the elastic body via a connecting plate and the bottom of the connecting plate below the elastic body is connected to a circular base plate, which is called the upper structure. The upper surface of the lower fixing plate has a groove structure with a concave center and convex edges to accommodate the base plate of the upper structure and allow the base plate to rotate and translate 1-3 mm within the concave shape of the lower fixing plate; or the lower fixing plate is fixed with a polyethylene liner through its concave part, and the upper surface of the polyethylene liner is concave to accommodate the base plate and allow the base plate to rotate and translate 1-3 mm within the concave shape of the polyethylene; the connecting plate is a solid plate structure or a hollow plate structure.

[0017] By adopting the above technical solution, the artificial intervertebral disc with rebound function is either integrally molded or a split structure. It is made of medical biomaterials such as titanium alloy. When integrated, it can be used for patients with low activity levels. During operation, it generates no wear particles, solving the problems of loosening and detachment of components and the inflammatory reactions caused by wear particles that can lead to patient discomfort in modular artificial intervertebral discs. Whether integral or split, the artificial intervertebral disc exhibits excellent axial elastic compression and rebound function during operation. It can achieve good compression and rebound of the surgical segment of the spine along the longitudinal axis of the body, and also achieve elastic stability in flexion and extension in the sagittal plane, lateral bending in the left and right directions, rotation in the coronal plane, and circumduction formed by combined movements in multiple directions. It has advantages such as simple structure, convenient implantation, stable fixation, strong axial elastic buffering force, good rebound, and long-lasting elasticity, meeting the needs of long-term physiological activities of the human spine. Furthermore, when some cases require vertebral body resection during surgery, this invention can also be used for cases with long-segment intervertebral defects after vertebral body resection and intervertebral disc resection.

[0018] Compared with existing technologies, the beneficial effects and advantages of this novel artificial intervertebral disc with a rebound function are as follows:

[0019] 1. This utility model uses a unique partially open circular shape as the main body of the elastic structure. The opening of the circle is connected to a connecting plate. The longitudinal pressure from the spine is reduced by the connecting plate, which can buffer the axial pressure of the spine. As the opening of the circle becomes smaller, the rebound force of the circle gradually increases as the gap between the openings decreases, thus having a good rebound function.

[0020] 2. In this utility model, the upper fixing plate and the lower fixing plate are fixedly connected to the middle of the pin or are movably connected to the pin. The pin can be inserted into the middle of the vertebral body for more stable fixation. The extension plate of the fixing plate is also provided with screw holes for screw assistance or pin holes for pin assistance, so as to further enhance the fixation effect.

[0021] 3. The outer surface of the fixation plate of this utility model has been treated with porosity and sprayed with a biological coating such as hydroxyapatite to facilitate bone ingrowth after implantation. The fixation plate is also provided with large round holes to facilitate bone embedding or ingrowth, thereby further enhancing the long-term stability after prosthesis placement.

[0022] 4. When this utility model is designed as an integrated unit, it can be used for patients with low activity levels. No wear particles are generated during its operation, which solves the problems of easy loosening and detachment of components and the inflammatory reaction caused by wear particles in combined artificial intervertebral discs, which can easily lead to patient discomfort.

[0023] 5. When this utility model is designed as an integral or separate unit, it has good axial elastic compression and rebound function during operation. It can achieve good compression and rebound of the surgical segment of the spine in the longitudinal direction of the human body, and can also achieve elastic stability of flexion and extension in the sagittal position, lateral bending in the left and right directions, rotation in the coronal position, and circumduction formed by comprehensive movements in multiple directions.

[0024] 6. This utility model has the advantages of simple structure, convenient implantation, stable fixation, strong axial elastic buffering force, good resilience, and long-lasting elasticity, meeting the needs of long-term physiological activities of the human spine. In some cases where vertebral resection is required during surgery, this utility model can also be used for cases of long-segment intervertebral defects after vertebral resection and intervertebral disc resection. Attached Figure Description

[0025] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the artificial intervertebral disc with rebound function of this utility model.

[0027] Figure 2 This is a schematic diagram of the structure of this utility model without a pin;

[0028] Figure 3 This is a schematic diagram of the structure of the elastic monomer in this utility model, which consists of two circular openings facing each other, connected to a connecting plate and then to upper and lower fixing plates.

[0029] Figure 4 This is a schematic diagram of the structure of the present invention, in which the elastic single unit is a partially open circle connected to the connecting plate and then to the upper fixing plate to form a whole, and the lower connecting plate is connected to a circular base plate.

[0030] Figure 5 This is a schematic diagram of the structure in this utility model in which locking screws are installed on the extension plate;

[0031] Figure 6 This is a schematic diagram showing that the elastic single unit in this utility model consists of three sets of opposing open circles connected to the connecting plate and then integrated with the upper and lower fixing plates, and fixed by pins and screws.

[0032] Figure 7 This is a schematic diagram showing that the elastic monomer in this utility model consists of a set of opposing open circles and two circles with different opening directions, which are connected to the connecting plate and then integrated with the upper and lower fixing plates.

[0033] Figure 8 This is a schematic diagram of the pin structure in this utility model;

[0034] Figure 9 This is a schematic diagram of the lower fixing plate in this utility model. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] See below. Figures 1 to 9 This invention provides a detailed description of the artificial intervertebral disc with a rebound function.

[0037] The present invention relates to an artificial intervertebral disc with a rebound function, comprising an artificial intervertebral disc body, which is either an integrally molded structure or a split structure; the artificial intervertebral disc body includes an upper fixation plate 1, a lower fixation plate 2, and an elastic body 3 disposed between the upper fixation plate 1 and the lower fixation plate 2; the outer surfaces of the upper fixation plate 1 and the lower fixation plate 2 are respectively provided with micropores and a hydroxyapatite-induced bone ingrowth bio-coating, and the upper fixation plate 1 and the lower fixation plate 2 are respectively provided with multiple round holes 4 and fixing teeth 5; the distance between one end port of the upper fixation plate 1 and the lower fixation plate 2 is greater than the distance between the other end port; the elastic body 3 is composed of one or more sets of elastic monomers.

[0038] Multiple fixing teeth 5 are evenly distributed on the upper fixing plate 1 or the lower fixing plate 2, and the tips of the fixing teeth 5 are sharp. The purpose of setting the fixing teeth 5 in this way is to enable each fixing tooth to engage with the end face of the vertebra at multiple points, thereby fixing the artificial intervertebral disc between the vertebrae.

[0039] Specifically, the upper fixation plate 1 or the lower fixation plate 2 is either circular or non-circular. In practical applications, the outer surface of the upper fixation plate 1 or the lower fixation plate 2 is either arc-shaped or flat. When the surface of the upper fixation plate 1 or the lower fixation plate 2 is arc-shaped, its curvature corresponds to the curvature of the vertebral end face. When the surface of the upper fixation plate 1 or the lower fixation plate 2 is flat, its plane corresponds to the abraded vertebral end face. The purpose of this arrangement is to ensure that the upper and lower surfaces of the upper fixation plate or the lower fixation plate are in close contact with the upper and lower end faces of the vertebra, thereby increasing the stress-bearing area.

[0040] Specifically, the upper fixation plate 1 or the lower fixation plate 2 may or may not have an extension plate 6. The corner surface of the upper fixation plate 1 or the lower fixation plate 2 connected to the vertebral body is flat or convex. One end of the upper fixation plate 1 or the lower fixation plate 2 located at the large-spacing port may or may not have an extension plate 6. The extension plate 6 is provided with a circular screw hole 7. The circular screw hole 7 is provided with a locking thread for inserting a locking screw 8. One side of the circular screw hole 7 is provided with an anti-retraction screw 9 to prevent the locking screw 8 from retracting. Alternatively, the extension plate 6 at the end of the upper fixation plate 1 or the lower fixation plate 2 is provided with a pin hole 10 for use with a pin 11 for auxiliary fixation during surgery. The pin 11 is provided with a pin base 11-1 larger than the pin hole 10. The pin hole 10 is designed in a stepped shape to prevent the pin base 11-1 from dislodging towards the vertebral body. The pin 11 is provided with an anti-retraction tooth 11-2 to prevent the pin from retracting away from the vertebral body.

[0041] The pin can be inserted into the vertebral body bone through the upper or lower fixation plate to achieve a more stable fixation. The extension plate of the upper or lower fixation plate is provided with screw holes or pin holes. The screw holes are provided with locking threads. The locking screw can be fixed to the vertebral body through the screw holes, or the pin can be fixed to the vertebral body through the pin holes to further enhance the fixation effect of the fixation plate on the vertebral body.

[0042] Among them, the distance between one end of the upper fixation plate 1 and the lower fixation plate 2 is greater than the distance between the other end to adapt to the physiological lordosis of the normal human spine; and because the range and frequency of the human body's head-down and waist-bending movements are much greater than the range and frequency of the human body's backward, rotation and lateral bending movements; therefore, when this artificial intervertebral disc is assembled, the large-distance port of the fixation plate is located in the anterior part of the intervertebral space.

[0043] The upper fixation plate 1 or lower fixation plate 2 located at the large-spacing port has an extension plate 6 at one end. The purpose of setting the extension plate 6 at one end of the upper fixation plate 1 or lower fixation plate 2 at the large-spacing port is to ensure that when the artificial intervertebral disc is inserted into the vertebrae from the front during surgery, the connecting plate can correspond to the anterior surface of the vertebra. This avoids the problem of the extension plate obstructing the insertion of the artificial intervertebral disc, and also allows the artificial intervertebral disc to be fixedly connected to the vertebra from front to back through the extension plate and screws or pins, so as to enhance the fixation effect and maintain the physiological lordosis of the spine in the surgical segment after the prosthesis is implanted. When used for the human lumbar spine, another design is that the extension plate on the upper fixation plate or lower fixation plate is set on the side, so that some doctors are accustomed to performing artificial intervertebral disc implantation from the side.

[0044] Specifically, the elastic body 3 is composed of one or two sets of elastic monomers; the upper fixing plate 1 and the lower fixing plate 2 at the gap between the two sets of elastic monomers are fixedly connected with pins or have pin holes and are equipped with movable pins 11; when the elastic body 3 is composed of a set of monomers, the upper fixing plate 1 or the lower fixing plate 2 at the front and / or side of the elastic body are fixedly connected with pins or have pin holes and are equipped with movable pins 11.

[0045] Specifically, the movable pin 11 is initially fitted into the pin hole on the upper fixing plate 1 or the lower fixing plate 2, with its tip slightly protruding from the surface of the upper fixing plate 1 or the lower fixing plate 2. The pin 11 has an expansion joint 11-3 in the middle, anti-retraction teeth 11-2 on both sides, and a pin base 11-1 at the bottom to prevent the pin from dislodging towards the vertebral body. When the pin 11 moves into the vertebral body from the pin hole on the upper fixing plate 1 or the lower fixing plate 2, the anti-retraction teeth 11-2 on both sides of the pin 11 can be engaged with the surface of the upper fixing plate 1 or the lower fixing plate 2, thus preventing it from dislodging away from the vertebral body. Furthermore, the pin base at the bottom of the pin 11 is larger than the pin hole, so the pin cannot dislodge through the fixing plate into the vertebral body.

[0046] As a variation of this utility model, the set of elastic units consists of a partially open circular 3-1 connected to a connecting plate 3-2 and then integrated with an upper fixing plate 1, with a circular base plate 3-3 connected to the lower connecting plate 3-2.

[0047] As another variation of this utility model, the set of elastic units is connected to a connecting plate 3-2 via a partially open circular 3-1. The upper connecting plate 3-2 is integrated with the upper fixing plate 1, and the lower connecting plate 3-2 is connected to a circular base 3-3, which in turn contacts the lower fixing plate 2 (split type). Alternatively, the elastic unit can be integrated with the upper fixing plate 1 and the lower fixing plate 2 via the connecting plate 3-2 (integrated type). This configuration can better increase the range of motion after prosthesis implantation, especially the range of motion of the spine in the anterior-posterior direction, because the range of motion of the spine flexion is significantly greater than that of extension, and much greater than that of lateral bending and rotation. This is suitable for cases with a large range of motion of the spine flexion and extension.

[0048] As another variation of this utility model, the set of elastic monomers consists of two opposing open circular sections 3-1 connected to a connecting plate 3-2, which is then integrated with the upper fixing plate 1 and contacts the lower fixing plate 2 (separate type); or the set of elastic monomers consists of two opposing open circular sections 3-1 connected to a connecting plate 3-2, which is then integrated with both the upper fixing plate 1 and the lower fixing plate 2 (integrated type). This configuration can better increase the mobility and stability of the prosthesis after implantation, and is suitable for cases with limited mobility.

[0049] As another variation of this utility model, the set of elastic monomers consists of three sets of opposing open circular joints 3-1 connected to a connecting plate 3-2, which are then connected to the upper fixing plate 1 and the lower fixing plate 2 respectively to form a whole. This can be used for cases with moderate mobility and vertebral body and intervertebral disc resection.

[0050] As another variation of this utility model, the set of elastic units consists of a set of oppositely opening circular 3-1s and two circular 3-1s partially opening in the same direction connected to the connecting plate 3-2, and then connected to the upper fixing plate 1 and the lower fixing plate 2 respectively to form a whole.

[0051] As another variation of this utility model, the set of elastic monomers consists of a set of circular 3-1s with openings facing each other and two circular 3-1s with opening directions in different directions connected to the connecting plate 3-2, and then connected to the upper fixing plate and the lower fixing plate respectively to form a whole; thus, it can be used for cases with large range of motion in extension and flexion.

[0052] As another variation of this utility model, the set of elastic units consists of four circular parts 3-1 with openings connected together and then connected to the upper fixing plate 1 and the lower fixing plate 2 respectively to form a whole; it has good elastic buffering and rebound function in the longitudinal axis of the spine.

[0053] As another variation of this utility model, the set of elastic units consists of three circular openings 3-1 in the same direction connected to the upper fixing plate 1 and the lower fixing plate 2 respectively through connecting plates 3-2.

[0054] As another variation of this utility model, the set of elastic monomers consists of a set of partially open circular segments 3-1 connected by a connecting plate 3-2, plus another set of partially open circular segments 3-1 directly connected, which are then integrated with the upper fixing plate 1 and the lower fixing plate 2 respectively. This is used for cases with relatively large mobility and vertebral body and intervertebral disc resection.

[0055] The upper fixing plate 1 and the lower fixing plate 2 are connected to the elastic body 3 by the connecting plate 3-2, or the upper fixing plate 1 is connected to the elastic body 3 by the connecting plate 3-2 and the bottom of the connecting plate 3-2 below the elastic body 3 is connected to a circular base plate 3-3, which is called the upper structure. The upper surface of the lower fixing plate 2 has a groove structure 2-1 with a concave center and convex edges to accommodate the circular base plate 3-3 of the upper structure and allow the circular base plate 3-3 to rotate and translate 1-3 mm within the concave shape on the lower fixing plate 2; or the lower fixing plate 2 is fixed to a polyethylene liner through its concave part, and the upper surface of the polyethylene liner is concave to accommodate the base plate and allow the base plate to rotate and translate 1-3 mm within the concave shape of the polyethylene liner; the connecting plate 3-2 is a solid plate structure or a hollow plate structure.

[0056] In this embodiment, when the present invention is an integrated structure, it can be used for patients with low activity levels. During operation, no wear particles are generated, solving the problems of loosening and detachment of components and the inflammatory reaction caused by wear particles in combined artificial intervertebral discs, which can lead to patient discomfort. When it is a split design, it not only has good axial elastic compression and rebound functions during operation, but also fully realizes flexion and extension in the sagittal plane, lateral bending in the left and right directions, translation in the front, back, left, and right directions, rotation in the coronal plane, and comprehensive movements in multiple directions. Its base and lower fixation plate have a large contact area, resulting in a wider stress distribution during movement and thus strong wear resistance. Furthermore, when used for patients with high activity levels, a highly cross-linked polyethylene liner can be fixed to the lower fixation plate to further increase wear resistance.

[0057] When the resilient artificial intervertebral disc is an integral structure, during its implantation into a patient with spinal disorders, the upper and lower vertebral endplates are first prepared. Then, the artificial intervertebral disc is gently hammered into the intervertebral space from the front or side. Next, the matching awl is used to awl the lateral pin into the vertebral body. Finally, as needed, the pin can be awled into the vertebral body through the insertion hole on the extension plate to strengthen fixation, or it can be fixed to the vertebral body with a locking screw through the screw hole on the extension plate. The anti-removal screw next to the screw hole is then turned so that the tail cap of the anti-removal screw presses against the tail cap of the locking screw to prevent the locking screw from loosening or coming out later.

[0058] In summary, this invention utilizes an elastomer to achieve axial compression and rebound of the spinal surgical segment along the longitudinal axis of the spine, flexion and extension in the sagittal plane, lateral bending in the left and right directions, rotation in the coronal plane, and circumferential elastic movement formed by combined movements in multiple directions. It features short operation time, convenient implantation, and stable fixation. It exhibits excellent axial buffering and rebound performance along the longitudinal axis of the human spine, and strong resistance to elastic decay, adapting to the physiological activity patterns of the human spine. When vertebral resection during surgery results in a long segmental intervertebral defect, this invention can also be used in cases of long-segmental intervertebral defects following vertebral resection and discectomy to reconstruct long-distance dynamic stability between the vertebral bodies.

[0059] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any transformations or substitutions that can be understood by those skilled in the art within the technical scope disclosed in this utility model should be included within the scope of this utility model.

Claims

1. An artificial intervertebral disc with a rebound function, comprising an artificial intervertebral disc body, characterized in that, The artificial intervertebral disc body is a one-piece molded structure or a split structure; the artificial intervertebral disc body includes an upper fixation plate, a lower fixation plate, and an elastomer disposed between the upper fixation plate and the lower fixation plate; the outer surfaces of the upper fixation plate and the lower fixation plate are respectively covered with micropores and a hydroxyapatite-induced bone ingrowth bio-coating; the upper fixation plate and the lower fixation plate are respectively provided with multiple round holes and fixation teeth; the distance between one end port of the upper fixation plate and the lower fixation plate is greater than the distance between the other end ports; the elastomer is composed of one or more sets of elastic monomers.

2. The artificial intervertebral disc with rebound function according to claim 1, characterized in that, The upper or lower fixation plate is either circular or non-circular in structure. The upper or lower fixation plate may or may not have an extension plate. The angle at which the upper or lower fixation plate connects to the vertebral body is either flat or convex. One end of the upper or lower fixation plate at the large-spacing port may or may not have an extension plate. The extension plate has a circular screw hole with a locking thread for inserting a locking screw. One side of the circular screw hole has an anti-retraction screw to prevent the locking screw from retracting. Alternatively, the extension plate at the end of the upper or lower fixation plate may have a pin hole for intraoperative pin-assisted fixation. The pin has a pin base larger than the pin hole, and the pin hole has a stepped design to prevent the pin base from dislodging towards the vertebral body. The pin has anti-retraction teeth to prevent the pin from retracting away from the vertebral body.

3. The artificial intervertebral disc with rebound function according to claim 2, characterized in that, The elastomer is composed of one or two sets of elastic monomers; the upper and lower fixing plates in the gap between the two sets of elastic monomers are fixedly connected with pins or have pin holes and are equipped with movable pins; when the elastomer is composed of a set of monomers, the upper or lower fixing plates in front of and / or on the side of the elastomer are fixedly connected with pins or have pin holes and are equipped with movable pins.

4. The artificial intervertebral disc with rebound function according to claim 3, characterized in that, The movable pin is initially fitted into the pin holes on the upper and lower fixing plates. The tip of the pin protrudes slightly from the surface of the upper or lower fixing plate. The pin has an expansion joint in the middle, anti-retraction teeth on both sides, and a pin base at the bottom to prevent the pin from dislodging towards the vertebral body. When the pin moves into the vertebral body from the pin hole on the upper or lower fixing plate, the anti-retraction teeth on both sides can be locked onto the surface of the upper or lower fixing plate, thus preventing it from dislodging away from the vertebral body.

5. The artificial intervertebral disc with rebound function according to claim 3, characterized in that, The set of elastic units consists of a partially open circular part connected to a connecting plate and then to an upper fixed plate, with a circular base plate connected to the lower connecting plate. The set of elastic units is connected to a connecting plate by a partially open circular part. The upper connecting plate is integrated with the upper fixed plate, and the lower connecting plate is connected to the circular base and then contacts the lower fixed plate through the circular base. Alternatively, the elastic unit is integrated with the upper and lower fixed plates through the connecting plate.

6. The artificial intervertebral disc with rebound function according to claim 3, characterized in that, The set of elastic units consists of two opposing circular openings connected to a connecting plate, which is then integrated with the upper fixing plate and finally in contact with the lower fixing plate. Alternatively, a set of elastic units consists of two opposing circular openings connected to a connecting plate, which is then integrated with the upper fixing plate and the lower fixing plate respectively.

7. The artificial intervertebral disc with rebound function according to claim 3, characterized in that, The aforementioned set of elastic monomers consists of three sets of opposing open circles connected to the connecting plate, and then respectively connected to the upper fixing plate and the lower fixing plate to form a whole.

8. The artificial intervertebral disc with rebound function according to claim 3, characterized in that, The set of elastic monomers consists of a set of oppositely opening circles and two circles with partial openings in the same direction, which are connected to the connecting plate and then connected to the upper fixing plate and the lower fixing plate respectively to form a whole. The set of elastic monomers consists of a set of circles with openings facing each other and two circles with opening directions in different directions, which are connected to the connecting plate and then connected to the upper fixing plate and the lower fixing plate respectively to form a whole. The aforementioned set of elastic monomers consists of four circular openings connected together, which are then connected to the upper fixing plate and the lower fixing plate to form a whole. The set of elastic monomers consists of three circular openings in the same direction, which are connected to the upper fixing plate and the lower fixing plate respectively through connecting plates. The set of elastic monomers consists of a set of partially open circles connected by a connecting plate, plus another set of partially open circles directly connected, which are then connected to the upper fixing plate and the lower fixing plate to form a whole.

9. The artificial intervertebral disc with rebound function according to claim 1, characterized in that, The multiple fixing teeth are evenly distributed on the upper fixing plate and the lower fixing plate.

10. The artificial intervertebral disc with rebound function according to claim 1, characterized in that, The upper and lower fixing plates are integrated with the elastic body via a connecting plate, or the upper fixing plate is integrated with the elastic body via a connecting plate and the bottom of the connecting plate below the elastic body is connected to a circular base plate, which is called the upper structure. The upper surface of the lower fixing plate has a groove structure with a concave center and convex edges to accommodate the base plate of the upper structure and allow the base plate to rotate and translate 1-3 mm within the concave shape of the lower fixing plate; or the lower fixing plate is fixed with a polyethylene liner through its concave part, and the upper surface of the polyethylene liner is concave to accommodate the base plate and allow the base plate to rotate and translate 1-3 mm within the concave shape of the polyethylene. The connecting plate is a solid plate structure or a hollow plate structure.

Images