Bionic intervertebral disc with endplate-anulus fibrosus self-locking fixation structure
By introducing transverse and longitudinal limiting structures and a self-locking fixation method using U-shaped fiber cables into the bionic intervertebral disc, the problem of loose connection between the endplate and the annulus fibrosus is solved, improving connection stability and lifespan, maintaining the mechanical properties of the annulus fibrosus, and adapting to different working conditions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JILIN UNIVERSITY
- Filing Date
- 2026-05-13
- Publication Date
- 2026-07-21
AI Technical Summary
In existing bionic intervertebral discs, the connection between the endplate and the annulus fibrosus has problems such as insufficient connection stability, easy loosening, displacement, or even failure during long-term service, which affects the overall stability and service life.
A self-locking fixing system for the end plate and fiber ring is constructed by adopting a transverse end plate-fiber ring limiting structure and a longitudinal end plate-fiber ring limiting structure, combined with the tension of the U-shaped fiber cable and the unidirectional limiting of the locking tube. The movement of the end plate and fiber ring is restricted by the transverse and longitudinal limiting structures, and the tension is transmitted between the upper and lower end plates by the fiber cable.
It significantly improves the stability and reliability of the connection, extends the in vivo service life of the bionic intervertebral disc, maintains the mechanical integrity of the annulus fibrosus, reduces local stress concentration, and adapts to different working conditions and individual differences.
Smart Images
Figure CN122208348B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of bionic intervertebral disc technology, specifically to a bionic intervertebral disc with a self-locking fixation structure of endplate-annulus fibrosus. Background Technology
[0002] Intervertebral discs are important cartilaginous tissues connecting adjacent vertebrae, playing a vital biomechanical role in maintaining spinal stability, bearing axial loads, and cushioning impacts. With age and long-term stress, the intervertebral discs of the human spine, especially the lumbar intervertebral discs, are highly susceptible to degenerative changes, mainly manifested as dehydration of the nucleus pulposus, destruction of the annulus fibrosus structure, and reduced intervertebral disc height, leading to clinical symptoms such as low back and leg pain, which seriously affects patients' learning, work, and daily life. For intervertebral disc degeneration, various effective treatment methods have been developed clinically, including fusion surgery and artificial disc replacement. Among them, artificial disc replacement has the significant advantage of relieving low back and leg pain symptoms while preserving segmental mobility, and has therefore gradually gained widespread attention and application worldwide.
[0003] With the rapid development of artificial intervertebral disc technology, some common problems of artificial intervertebral disc devices have gradually emerged. For example, their single-material isotropic design is fundamentally different from the heterogeneous gradient structure of natural intervertebral discs, which leads to significant differences in their structural mechanical properties and three-dimensional anisotropic motion function compared to natural intervertebral discs. To solve these problems, their structural form has gradually shifted from the early mechanical design based on rigid materials and joint structures to a biomimetic intervertebral disc design that simulates the structure and function of natural intervertebral discs.
[0004] Compared to traditional mechanical joint structures, bionic intervertebral discs typically employ multi-material composite structures, setting up functional zones similar to the nucleus pulposus and annulus fibrosus to achieve three-dimensional motion and mechanical response characteristics that more closely resemble those of natural intervertebral discs.
[0005] In biomimetic intervertebral disc structures, the connection method between the endplate and the annulus fibrosus has a significant impact on the overall stability and mechanical properties of the structure. Existing biomimetic intervertebral discs mainly use adhesive bonding, integral molding, mechanical bonding, and fiber-braided or wrapped structures for the connection between the endplate and the annulus fibrosus. Specifically, adhesive bonding uses specific adhesive materials to fix the two together; integral molding forms a continuous structure through integral manufacturing; mechanical bonding usually uses threads, snaps, or interlocking structures for fixation; and fiber-braided or wrapped structures achieve structural coupling through fiber paths.
[0006] However, in practical applications, the above-mentioned connection methods still have certain limitations in long-term service environments. For example, adhesive connections may be affected by factors such as temperature and humidity in the internal environment, and are prone to aging, degradation, or interface peeling, thus affecting their connection stability. In integral molding structures, the end plate usually needs to have high rigidity to bear axial loads, while the fiber ring needs to have good flexibility and anisotropic mechanical properties. There are significant differences between the two in terms of material properties and structural functions. Forced integral design often leads to limited material performance matching, making it difficult to simultaneously meet the requirements of rigidity and flexibility, thus affecting the overall functional effect. Mechanical connection methods may destroy the continuous structure of the fiber ring and generate local stress concentration in the connection area. Traditional fiber braiding or winding structures have the problem of uncontrollable tension, and the fibers are prone to loosening. The tension acts directly on the internal structure of the fiber ring, which can easily introduce shear or local stress concentration, thus affecting its long-term mechanical stability.
[0007] Under the combined effects of long-term complex loads and the internal environment, the above-mentioned problems may further lead to failure modes such as loosening of the connection between the endplate and the annulus fibrosus, structural displacement, or even endplate subsidence, resulting in a decrease in the overall stability and shortened service life of the bionic intervertebral disc. In severe cases, a second surgical intervention may be required.
[0008] Therefore, under the premise of ensuring the structural integrity and mechanical function of the annulus fibrosus, how to construct a connection structure between the endplate and the annulus fibrosus that can achieve stable self-locking fixation to avoid adverse effects on the internal structure of the annulus fibrosus, so as to improve the overall stability and long-term service performance of the biomimetic intervertebral disc, remains a technical problem to be solved in this field. Summary of the Invention
[0009] The purpose of this invention is to provide a bionic intervertebral disc with a self-locking fixation structure of endplate-annulus fibrosus, in order to solve the problems of insufficient connection stability, easy loosening, displacement or even failure of the connection method between the endplate and annulus fibrosus in the prior art during long-term service, especially the difficulty in achieving stable and reliable fixation while ensuring the structural integrity and mechanical function of the annulus fibrosus, thereby improving the overall stability and service life of the bionic intervertebral disc.
[0010] A biomimetic intervertebral disc with an endplate-annulus fibrosus self-locking fixation structure includes an upper endplate, a lower endplate, annulus fibrosus, a nucleus pulposus, and an endplate-annulus fibrosus self-locking fixation structure. The upper endplate and lower endplate are symmetrical in structure, the nucleus pulposus is located in the annulus fibrosus, and the annulus fibrosus is sandwiched between the upper endplate and the lower endplate. The endplate-fiber ring self-locking fixing structure includes a transverse endplate-fiber ring limiting structure and a longitudinal endplate-fiber ring limiting structure. The transverse endplate-fiber ring limiting structure includes a first arc-shaped protrusion on the upper surface of the fiber ring and a first circular protrusion in the middle, a first arc-shaped groove on the lower surface of the upper endplate and a first circular groove in the middle, a second arc-shaped protrusion on the lower surface of the fiber ring and a second circular protrusion in the middle, and a second arc-shaped groove on the upper surface of the lower endplate and a second circular groove in the middle. The first arc-shaped protrusion on the fiber ring is engaged in the first arc-shaped groove on the lower surface of the upper end plate, and the first circular protrusion on the upper surface of the fiber ring is engaged in the first circular groove on the lower surface of the upper end plate. In this way, the lateral movement between the upper end plate and the fiber ring is restricted. The second arc-shaped protrusion on the lower surface of the fiber ring is engaged in the second arc-shaped groove on the upper surface of the lower end plate, and the second circular protrusion on the lower surface of the fiber ring is engaged in the second circular groove on the upper surface of the lower end plate, thus restricting the lateral movement between the lower end plate and the fiber ring.
[0011] The longitudinal endplate-fiber ring limiting structure includes a plurality of fiber cables, which are circumferentially distributed at equal intervals. Each fiber cable passes through a through hole in the fiber ring. The lower end of the fiber cable is fixed to the upper surface of the lower endplate, and the upper end of the fiber cable is fixed to the lower surface of the upper endplate. In this way, the fiber cables restrict the longitudinal movement between the upper endplate and the fiber ring, as well as between the lower endplate and the fiber ring.
[0012] The fiber cables consist of eight U-shaped cables. Four of the U-shaped fiber cables have their U-shaped openings facing upwards, while the other four have their U-shaped openings facing downwards. The U-shaped fiber cables with their U-shaped openings facing upwards and downwards are spaced apart. The fiber rings have double-hole through-holes through which the U-shaped fiber cables pass. The installation structure of the U-shaped fiber cable with the U-shaped opening facing downward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the first locking block on the first outer ring plate of the upper end plate, and the open end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the second blind hole on the second outer ring plate of the lower end plate and is fixed with the second bolt. The other fiber cable passes through the second locking tube on the second inner ring plate of the lower end plate, and is fixed with the first bolt after being tightened. In this way, the U-shaped fiber cable with the U-shaped opening facing downward restricts the longitudinal movement between the upper end plate and the fiber ring and between the lower end plate and the fiber ring.
[0013] The installation structure of the U-shaped fiber cable with the U-shaped opening facing upward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing upward passes through the second locking block on the second outer ring plate of the lower end plate, and the open end of the U-shaped fiber cable with the U-shaped opening facing upward passes through the first blind hole on the first outer ring plate of the upper end plate and is fixed with the second bolt. The other fiber cable passes through the first locking tube on the first inner ring plate of the upper end plate, is tightened and fixed with the first bolt. In this way, the U-shaped fiber cable with the U-shaped opening facing upward restricts the longitudinal movement between the upper end plate and the fiber ring and between the lower end plate and the fiber ring.
[0014] The transverse endplate-fiber ring limiting structure further includes a first locking block, a second locking block, and a slot on the fiber ring. The slot is located on the through hole, and the positions of the first locking block and the second locking block correspond to the slot. The first locking block and the second locking block are both locked in the slot, which restricts the transverse movement between the upper endplate and the fiber ring, and between the lower endplate and the fiber ring.
[0015] The upper end plate has a central cover plate, which is fixedly connected to the first outer ring plate through a through hole on its outer edge and bolts, and is fixedly connected to the first inner ring plate through a through hole in its center and bolts. The lower end plate also has a central cover plate, which is fixedly connected to the second outer ring plate through a through hole on its outer edge and bolts, and is fixedly connected to the second inner ring plate through a through hole in its center and bolts. The upper surface of the upper end plate and the lower surface of the lower end plate are both provided with end plate fixing teeth.
[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. High connection stability and significantly extended in vivo service life: This invention uses a self-locking fixation structure for the endplate-annulus fibrosus, consisting of a transverse endplate-annulus fibrosus limiting structure and a longitudinal endplate-annulus fibrosus limiting structure. Combined with the tension generated by the U-shaped fiber cable routing and the unidirectional limiting of the locking tube, a self-locking fixation system is constructed between the endplate and the annulus fibrosus. This makes the connection structure less prone to loosening or failure under complex loads and the internal environment, thereby significantly improving connection reliability and extending the in vivo service life of the bionic intervertebral disc.
[0017] 2. Controllable tension path, maintaining the integrity of the fiber ring and its mechanical function: The fiber cable passes directly through the fiber ring, so that the connection tension mainly acts between the upper and lower end plates, avoiding the tension acting directly on the inside of the fiber ring, thereby reducing the risk of shear damage; at the same time, the tension acts on the end face of the fiber ring in the form of axial compression, which, combined with its large force-bearing area, helps to reduce local stress concentration, and maintains the load-bearing and buffering function of the fiber ring while achieving a stable connection.
[0018] 3. Reasonable structural design, good adaptability and engineering feasibility: The present invention has a simple structure and easy assembly process. The tension of the U-shaped fiber cable closed loop routing structure is adjustable, which can adapt to different working conditions and individual differences. The components work together through interlocking and mechanical fixing, which helps to improve the overall structural consistency and practical application performance. Attached Figure Description
[0019] Figure 1 This is a three-dimensional schematic diagram of the fiber ring transparency of the present invention; Figure 2 This is a three-dimensional schematic diagram of the fiber ring transparency of the present invention from a bottom view angle; Figure 3 This is a three-dimensional schematic diagram of the present invention, showing the upper endplate and fiber ring as transparent. Figure 4 This is a partial three-dimensional schematic diagram showing the first card block and the first card locking tube of the present invention; Figure 5 This is a partial perspective view of the second card block and the second card locking tube of the present invention; Figure 6 This is a three-dimensional schematic diagram showing the structure of the upper surface of the fiber ring according to the present invention: Figure 7 This is a three-dimensional schematic diagram showing the structure of the lower surface of the fiber ring according to the present invention: Figure 8 This is a three-dimensional schematic diagram of the surface structure of the first outer ring plate and the second outer ring plate of the present invention; Figure 9 This is a three-dimensional schematic diagram of the surface structure of the first inner ring plate and the second inner ring plate of the present invention; Figure 10 This is another three-dimensional schematic diagram showing the structure of the upper surface of the fiber ring according to the present invention: Figure 11 This is another three-dimensional schematic diagram showing the structure of the lower surface of the fiber ring according to the present invention: Figure 12 This is a three-dimensional schematic diagram of the present invention: Figure 13 This is a three-dimensional view of the present invention with the central cover plate removed: Figure 14 This is a bottom-view perspective view of the present invention with the fiber rings concealed: Figure 15 This is a top-view perspective view of the invention with the fiber rings concealed: Figure 16 Another perspective view of the present invention with the fiber rings concealed from view; Figure 17 The data graph for Experiment 1; Figure 18 This is a data graph from Experiment 2.
[0020] In the diagram: 1—Upper endplate; 11—First arc-shaped groove; 12—First circular groove; 13—First outer ring plate; 14—First blind hole; 15—First inner ring plate; 16—First locking tube; 17—Central cover plate; 2—Lower endplate; 21—Second arc-shaped groove; 22—Second circular groove; 23—Second outer ring plate; 24—Second blind hole; 25—Second inner ring plate; 26—Second locking tube; 3—Fiber ring; 31—First arc-shaped protrusion; 32—First circular protrusion; 33—Second arc-shaped protrusion; 34—Second circular protrusion; 35—Through hole; 36—Slot; 4—Nucleus pulposus; 5—Fiber cable; 6—First locking block; 7—Second locking block; 8—First bolt; 9—Second bolt; 10—Endplate fixing tooth. Detailed Implementation
[0021] Please see Figures 1 to 16 The image shown is an embodiment of the present invention.
[0022] A biomimetic intervertebral disc with an endplate-annulus fibrosus self-locking fixation structure includes an upper endplate 1, a lower endplate 2, annulus fibrosus 3, a nucleus pulposus 4, and an endplate-annulus fibrosus self-locking fixation structure. The upper endplate 1 and the lower endplate 2 are symmetrical in structure. The nucleus pulposus 4 is disposed in the annulus fibrosus 3, and the annulus fibrosus 3 is sandwiched between the upper endplate 1 and the lower endplate 2. The endplate-fiber ring self-locking fixing structure includes a transverse endplate-fiber ring limiting structure and a longitudinal endplate-fiber ring limiting structure. The transverse endplate-fiber ring limiting structure includes a first arc-shaped protrusion 31 and a first circular protrusion 32 on the upper surface of the fiber ring 3, a first arc-shaped groove 11 and a first circular groove 12 on the lower surface of the upper endplate 1, a second arc-shaped protrusion 33 and a second circular protrusion 34 on the lower surface of the fiber ring 3, and a second arc-shaped groove 21 and a second circular groove 22 on the upper surface of the lower endplate 2. The first arc-shaped protrusion 31 on the fiber ring 3 is engaged in the first arc-shaped groove 11 on the lower surface of the upper end plate 1, and the first circular protrusion 32 on the upper surface of the fiber ring 3 is engaged in the first circular groove 12 on the lower surface of the upper end plate 1. In this way, the lateral movement between the upper end plate 1 and the fiber ring 3 is restricted. The second arc-shaped protrusion 33 on the lower surface of the fiber ring 3 is engaged in the second arc-shaped groove 21 on the upper surface of the lower end plate 2, and the second circular protrusion 34 on the lower surface of the fiber ring 3 is engaged in the second circular groove 22 on the upper surface of the lower end plate 2. In this way, the lateral movement between the lower end plate 2 and the fiber ring 3 is restricted.
[0023] The longitudinal endplate-fiber ring limiting structure includes a plurality of fiber cables 5, which are circumferentially distributed at equal intervals. Each fiber cable 5 passes through the through hole 35 of the fiber ring 3. The lower end of the fiber cable 5 is fixed to the upper surface of the lower endplate 2, and the upper end of the fiber cable 5 is fixed to the lower surface of the upper endplate 1. In this way, the fiber cables 5 restrict the longitudinal movement between the upper endplate 1 and the fiber ring 3, as well as between the lower endplate 2 and the fiber ring 3.
[0024] The fiber cables 5 consist of eight U-shaped fibers. Four of the U-shaped fibers have their U-shaped openings facing upwards, while the other four have their U-shaped openings facing downwards. The U-shaped fibers with their U-shaped openings facing upwards and downwards are spaced apart. The through hole 35 of the fiber ring 3 is a double-hole type through hole, through which the U-shaped fibers pass. The installation structure of the U-shaped fiber cable with the U-shaped opening facing downward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the first locking block 6 on the first outer ring plate 13 of the upper end plate 1. The open end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the second blind hole 24 on the second outer ring plate 23 of the lower end plate 2 and is fixed with the second bolt 9. The other fiber cable passes through the second locking tube 26 on the second inner ring plate 25 of the lower end plate 2 and is fixed with the first bolt 8 after being tightened. In this way, the U-shaped fiber cable with the U-shaped opening facing downward restricts the longitudinal movement between the upper end plate 1 and the fiber ring 3 and between the lower end plate 2 and the fiber ring 3.
[0025] The installation structure of the U-shaped fiber cable with the U-shaped opening facing upward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing upward passes through the second locking block 7 on the second outer ring plate 23 of the lower end plate 2. At the opening end of the U-shaped fiber cable with the U-shaped opening facing upward, one fiber cable passes through the first blind hole 14 on the first outer ring plate 13 of the upper end plate 1 and is fixed with the second bolt 9. The other fiber cable passes through the first locking tube 16 on the first inner ring plate 15 of the upper end plate 1 and is fixed with the first bolt 8 after being tightened. In this way, the U-shaped fiber cable with the U-shaped opening facing upward restricts the longitudinal movement between the upper end plate 1 and the fiber ring 3 and between the lower end plate 2 and the fiber ring 3.
[0026] The lateral endplate-fiber ring limiting structure also includes a first locking block 6, a second locking block 7, and a slot 36 on the fiber ring 3. The slot 36 is located on the through hole 35. The positions of the first locking block 6 and the second locking block 7 correspond to the slot 36. The first locking block 6 and the second locking block 7 are both locked in the slot 36, which restricts the lateral movement between the upper endplate 1 and the fiber ring 3, and between the lower endplate 2 and the fiber ring 3.
[0027] The upper end plate 1 has a central cover plate 17, which is fixedly connected to the first outer ring plate 13 through a through hole on its outer edge and bolts. The central cover plate 17 is also fixedly connected to the first inner ring plate 15 through a through hole in its center and bolts. The lower end plate 2 also has a central cover plate 17, which is fixedly connected to the second outer ring plate 23 through a through hole on its outer edge and bolts. The central cover plate 17 is also fixedly connected to the second inner ring plate 25 through a through hole in its center and bolts. End plate fixing teeth 10 are provided on the upper surface of the upper end plate 1 and the lower surface of the lower end plate 2.
[0028] Experiment 1: Experimental objective: To verify that the connection method of fiber cable 5 can still ensure structural stability under repeated loads, without affecting the fiber ring, and thus guarantee the lifespan of the fiber ring.
[0029] Experimental procedure: 1. Measure and record the pore size of the five sets of fiber rings using an image measuring instrument; 2. Assemble the five sets of bionic intervertebral discs, then fix the upper endplate 1 and lower endplate 2 onto the fatigue testing machine and clamp them together. Set the test frequency to a uniform sinusoidal waveform of 4Hz to simulate the frequency of normal human walking activities; set the peak load pressure to 1000N. 3. Set the number of cycles for the five groups to 100, 200, 300, 400, 500, and 600 respectively, and conduct repeated load experiments; 4. Carefully and slowly disassemble all the intervertebral discs, measure them again using an imaging measuring instrument, and collect data. The eight through holes 35 of the annulus fibrosus 3 are double-hole through holes. Among the 16 holes measured in each group, the hole with the largest change in hole diameter is taken as the characteristic value of the group. Then, calculate the percentage change in hole diameter for each group, and obtain the final fitting curve by integrating the five groups of data.
[0030] Experimental results: like Figure 17 As shown, due to the inherent material properties of the fiber ring 3, the deformation increases slightly with the increase of repeated loads, but the overall trend is a linear function. This proves that within the five groups, the fiber cable 5 has almost no effect on the aperture of the through hole 35 of the fiber ring 3, which shows that the present invention is reasonable and stable.
[0031] Experiment 2: Experimental objective: To verify the connection method of fiber cable 5, to ensure that fiber cable 5 can maintain its initial performance and state under repeated loads, and to verify that fiber cable 5 can ensure that there will be no significant performance degradation during the service life of the bionic intervertebral disc, and can fully achieve the expected results.
[0032] Experimental procedure: 1. Stretch each fiber using a micro tensile testing machine, read the stretching length in real time using the encoder of the micro tensile testing machine, and make the elongation change reach 5% of the original length of the fiber cable. Read the tensile reading of the testing machine and record it, and take the average value as the original characteristic value. 2. Assemble the five sets of bionic intervertebral discs, then fix the upper endplate 1 and lower endplate 2 onto the fatigue testing machine and clamp them. Set a uniform sine wave pattern and a test frequency of 4Hz to simulate the frequency of normal human walking activities; set the peak load pressure to 1000N. 3. Set the number of cycles for the five groups to 500, 1000, 1500, 2000, 2500, and 3000 respectively; 4. Carefully and slowly disassemble all the intervertebral discs, remove all the fiber cables 5 in each group, stretch each fiber cable 5 using a micro tensile testing machine, read the stretching length in real time using the encoder of the micro tensile testing machine, make the elongation change reach 5% of the original length of the fiber cable 5, read the tensile force reading of the testing machine and record it, and take the average value of each group. 5. Statistical analysis: Use the average of the five groups as the feature value of each group, and then integrate the five groups of data to obtain the final fitted curve.
[0033] Experimental results: like Figure 18 As shown, under repeated loads, the fiber cable 5 can still maintain its initial performance and state, proving that the fiber cable 5 can ensure that there will be no significant performance degradation during the service life of the bionic intervertebral disc, and can fully achieve the expected effect.
Claims
1. A biomimetic intervertebral disc with an endplate-annulus fibrosus self-locking fixation structure, comprising an upper endplate (1), a lower endplate (2), annulus fibrosus (3), and a nucleus pulposus (4), wherein the upper endplate (1) and the lower endplate (2) are structurally symmetrical, the nucleus pulposus (4) is disposed in the annulus fibrosus (3), the annulus fibrosus (3) is sandwiched between the upper endplate (1) and the lower endplate (2), and further comprising an endplate-annulus fibrosus self-locking fixation structure; wherein the endplate-annulus fibrosus self-locking fixation structure comprises a transverse endplate-annulus fibrosus limiting structure and a longitudinal endplate-annulus fibrosus limiting structure; The transverse endplate-fiber ring limiting structure includes a first arc-shaped protrusion (31) on the upper surface of the fiber ring (3) and a first circular protrusion (32) in the middle, a first arc-shaped groove (11) on the lower surface of the upper endplate (1) and a first circular groove (12) in the middle, a second arc-shaped protrusion (33) on the lower surface of the fiber ring (3) and a second circular protrusion (34) in the middle, and a second arc-shaped groove (21) on the upper surface of the lower endplate (2) and a second circular groove (22) in the middle. The first arc-shaped protrusion (31) on the fiber ring (3) is stuck in the first arc-shaped groove (11) on the lower surface of the upper end plate (1), and the first circular protrusion (32) on the upper surface of the fiber ring (3) is stuck in the first circular groove (12) on the lower surface of the upper end plate (1). The second arc-shaped protrusion (33) on the lower surface of the fiber ring (3) is engaged in the second arc-shaped groove (21) on the upper surface of the lower end plate (2), and the second circular protrusion (34) on the lower surface of the fiber ring (3) is engaged in the second circular groove (22) on the upper surface of the lower end plate (2); The longitudinal end plate-fiber ring limiting structure includes several fiber cables (5), which are circumferentially distributed at equal intervals. Each fiber cable (5) passes through a through hole (35) of the fiber ring (3). The lower end of each fiber cable (5) is fixed to the upper surface of the lower end plate (2), and the upper end of each fiber cable (5) is fixed to the lower surface of the upper end plate (1). There are eight fiber cables (5), each U-shaped. Four U-shaped fiber cables have their U-shaped openings facing upwards, and the other four have their U-shaped openings facing downwards. The U-shaped fiber cables with their U-shaped openings facing upwards and downwards are spaced apart. The through hole (35) of the fiber ring (3) is a double-hole type, through which the U-shaped fiber cables pass. The structure is characterized by: The installation structure of the U-shaped fiber cable with the U-shaped opening facing downward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the first locking block (6) on the first outer ring plate (13) of the upper end plate (1), and the opening end of the U-shaped fiber cable with the U-shaped opening facing downward passes through the second blind hole (24) on the second outer ring plate (23) of the lower end plate (2) and is fixed with the second bolt (9), and the other fiber cable passes through the second locking tube (26) on the second inner ring plate (25) of the lower end plate (2), and is fixed with the first bolt (8) after being tightened; The installation structure of the U-shaped fiber cable with the U-shaped opening facing upward is as follows: the arc end of the U-shaped fiber cable with the U-shaped opening facing upward passes through the second locking block (7) on the second outer ring plate (23) of the lower end plate (2), and the opening end of the U-shaped fiber cable with the U-shaped opening facing upward, one of the fiber cables passes through the first blind hole (14) on the first outer ring plate (13) of the upper end plate (1) and is fixed with the second bolt (9), and the other fiber cable passes through the first locking tube (16) of the first inner ring plate (15) of the upper end plate (1), and is fixed with the first bolt (8) after being tightened.
2. The biomimetic intervertebral disc with an endplate-annulus fibrosus self-locking fixation structure according to claim 1, characterized in that: The transverse end plate-fiber ring limiting structure also includes a first locking block (6), a second locking block (7), and a slot (36) on the fiber ring (3). The slot (36) is located on the through hole (35). The positions of the first locking block (6) and the second locking block (7) correspond to the slot (36). The first locking block (6) and the second locking block (7) are both locked in the slot (36).