Artificial intervertebral disc prosthesis

Abstract

The utility model relates to the field of surgical implants, in particular to an artificial intervertebral disc prosthesis which comprises an upper end plate, a nucleus pulposus and a lower end plate, the lower surface of the upper end plate is attached to the upper surface of the nucleus pulposus, the lower surface of the nucleus pulposus is attached to the upper surface of the lower end plate, a movable groove is formed in the lower surface of the nucleus pulposus, and a movable convex part is arranged on the upper surface of the lower end plate. The movable convex part is embedded in the movable groove, a gap is formed between the side wall of the movable convex part and the inner side wall of the movable groove, and the nucleus pulposus can move in the radial direction and rotate around the center shaft relative to the lower end plate through cooperation of the movable convex part and the movable concave part. In addition, the movable convex part is matched with the movable concave part to limit excessive movement and rotation of the nucleus pulposus, and the nucleus pulposus is prevented from being separated from the lower end plate under overlarge pressure.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of surgical implants, in particular to an artificial intervertebral disc prosthesis. BACKGROUND

[0002] Artificial intervertebral disc replacement surgery is an effective method for treating degenerative intervertebral disc disease, and it is increasingly replacing the currently commonly used spinal fusion surgery. Artificial intervertebral disc replacement attempts to stabilize the spine through a non-fusion method to eliminate discogenic pain while not sacrificing the function of the spinal motion segment. It uses an artificial intervertebral disc that meets certain biomechanical properties as an implant to replace the original natural lumbar intervertebral disc function.

[0003] CN103315830B discloses a person-shaped bidirectional anti-retreat inverted tooth omega type artificial cervical intervertebral disc implant prosthesis, which replaces the traditional spherical, saddle bearing structure with an omega-shaped non-contact elastic structure integrated with the upper and lower end plates, and the outer surface of the upper and lower end plates is provided with a person-shaped bidirectional anti-retreat inverted tooth for anchoring the upper and lower vertebrae. The surface stress state of the prosthesis and the vertebral body is improved to prolong the service life and resist fatigue. The prosthesis relies on the load-bearing capacity and impact energy absorption capacity of the omega-shaped non-contact elastic structure integrated with the upper and lower end plates to restore and maintain the height of the intervertebral space, maintain segment stability, and retain the flexion, extension movement and compression shock absorption function of the intervertebral disc. The disadvantage is that the prosthesis is an integrated structure, cannot rely on its own structure to achieve axial rotation, and cannot achieve normal human spinal movement.

[0004] CN204839838U discloses an artificial cervical intervertebral disc prosthesis, which includes an upper end plate, a lower end plate, and a wear-resistant nucleus pulposus arranged between the upper and lower end plates. It has a three-dimensional six-degree-of-freedom spatial activity range of rotation, flexion, extension and translation, and can meet the normal cervical motion function of the human body, solving the problems in the prior art. The disadvantage is that the nucleus pulposus is fixedly installed on the lower end plate, and the rotation center is fixed. The position of the nucleus pulposus of the cervical intervertebral disc is constantly changing during the relative movement of the cervical segment, i.e. it can provide a transiently variable rotation center. Therefore, the fixed rotation center does not conform to the actual state of the transiently variable rotation center of the human nucleus pulposus. UTILITY MODEL CONTENTS

[0005] In view of the shortcomings of the prior art, the utility model provides an artificial intervertebral disc prosthesis, which aims to solve the problem of fixed installation of the nucleus pulposus on the lower end plate and fixed rotation center.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0007] An artificial intervertebral disc prosthesis, comprising an upper endplate, a nucleus pulposus and a lower endplate, a lower surface of the upper endplate and an upper surface of the nucleus pulposus are fitted, a lower surface of the nucleus pulposus and an upper surface of the lower endplate are fitted, the lower surface of the nucleus pulposus is provided with a movable recess, the upper surface of the lower endplate is provided with a movable protrusion, the movable protrusion is embedded in the movable recess, and the side wall of the movable protrusion and the inner side wall of the movable recess have a gap, the cooperation of the movable protrusion and the movable recess enables the nucleus pulposus to move radially and rotate around the central axis relative to the lower endplate.

[0008] In some optional embodiments, the movable protrusion is located at the center of the upper surface of the lower endplate, the movable protrusion comprises a transverse protrusion and a longitudinal protrusion, the center of the transverse protrusion intersects with the center of the longitudinal protrusion to form a cross-shaped movable protrusion; the movable recess is located at the center of the lower surface of the nucleus pulposus, the movable recess comprises a transverse recess and a longitudinal recess, the center of the transverse recess intersects with the center of the longitudinal recess to form a cross-shaped movable recess; the transverse protrusion is embedded in the transverse recess, and the longitudinal protrusion is embedded in the longitudinal recess.

[0009] In some optional embodiments, the movable protrusion is located at the center of the upper surface of the lower endplate, the movable protrusion is a single-bar-shaped, the movable recess is located at the center of the lower surface of the nucleus pulposus, and the movable recess is a single-bar-shaped.

[0010] In some optional embodiments, the movable protrusion is located at the center of the upper surface of the lower endplate, the movable protrusion is an elliptic cylinder, the movable recess is located at the center of the lower surface of the nucleus pulposus, and the movable recess is an elliptic cylinder.

[0011] In some optional embodiments, the lower surface of the upper endplate and the upper surface of the nucleus pulposus form a ball-and-socket joint.

[0012] In some optional embodiments, the lower surface of the upper endplate is concavely provided with a spherical recess, the upper surface of the nucleus pulposus is convexly provided with a spherical dome, the ball-and-socket joint is formed by the spherical recess and the spherical dome, and the ball-and-socket joint enables the upper endplate to freely move in six directions of flexion / extension, left / right bending and left / right rotation relative to the nucleus pulposus.

[0013] In some optional embodiments, the upper surface of the upper endplate is provided with an arc-shaped protrusion, and the upper surface of the upper endplate is provided with a plurality of upper inverted teeth symmetrically or asymmetrically distributed around the arc-shaped protrusion.

[0014] In some optional embodiments, the lateral wall of the upper endplate is provided with a plurality of upper clamping recesses.

[0015] In some alternative embodiments, the lower surface of the lower endplate is provided with an oval protrusion, and the lower surface of the lower endplate is provided with a plurality of lower inverted teeth symmetrically or asymmetrically distributed around the oval protrusion.

[0016] In some alternative embodiments, the outer sidewall of the lower endplate is provided with a plurality of lower clamping grooves.

[0017] The artificial intervertebral disc prosthesis described in the utility model has the advantages of:

[0018] By providing the movable groove on the lower surface of the nucleus pulposus and the movable protrusion on the upper surface of the lower endplate, the movable protrusion is embedded in the movable groove, the sidewall of the movable protrusion has a gap with the inner sidewall of the movable groove, the rotation center of the nucleus pulposus can move, the movable protrusion and the movable groove cooperate to enable the nucleus pulposus to move in the radial direction and rotate around the central axis relative to the lower endplate, and in addition, the cooperation of the movable protrusion and the movable groove limits the excessive movement and rotation of the nucleus pulposus, preventing the nucleus pulposus from being detached from the lower endplate under excessive pressure. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is the overall structure schematic diagram of the artificial intervertebral disc prosthesis from one perspective of the utility model embodiment;

[0020] Figure 2 is the overall structure schematic diagram of the artificial intervertebral disc prosthesis from another perspective of the utility model embodiment;

[0021] Figure 3 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from one perspective of the utility model embodiment 1;

[0022] Figure 4 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from another perspective of the utility model embodiment 1;

[0023] Figure 5 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from one perspective of the utility model embodiment 2;

[0024] Figure 6 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from another perspective of the utility model embodiment 2;

[0025] Figure 7 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from one perspective of the utility model embodiment 3;

[0026] Figure 8 is the structure disassembly schematic diagram of the artificial intervertebral disc prosthesis from another perspective of the utility model embodiment 3.

[0027] MARKS DESCRIPTION:

[0028] 1, upper end plate; 11, spherical recess; 12, arc-shaped protrusion; 13, upper inverted tooth; 14, upper clamping groove; 2, nucleus; 21, movable recess; 211, transverse recess; 212, longitudinal recess; 22, spherical dome; 3, lower end plate; 31, movable protrusion; 311, transverse protrusion; 312, longitudinal protrusion; 32, oval protrusion; 33, lower inverted tooth; 34, lower clamping groove. DETAILED DESCRIPTION

[0029] The utility model will be further described below in combination with the drawings and specific embodiments.

[0030] As Figures 1 to 8 shown, an artificial intervertebral disc prosthesis comprises an upper end plate 1, a nucleus 2 and a lower end plate 3, the lower surface of the upper end plate 1 and the upper surface of the nucleus 2 are attached, the lower surface of the nucleus 2 and the upper surface of the lower end plate 3 are attached, the lower surface of the nucleus 2 is provided with a movable recess 21, the upper surface of the lower end plate 3 is provided with a movable protrusion 31, the movable protrusion 31 is embedded in the movable recess 21, and the side wall of the movable protrusion 31 and the inner side wall of the movable recess 21 have a gap, and the cooperation of the movable protrusion 31 and the movable recess enables the nucleus 2 to move in the radial direction and rotate around the central axis relative to the lower end plate 3.

[0031] By providing the movable recess 21 on the lower surface of the nucleus 2 and the movable protrusion 31 on the upper surface of the lower end plate 3, since the movable protrusion 31 is embedded in the movable recess 21, and the side wall of the movable protrusion 31 and the inner side wall of the movable recess 21 have a gap, the rotation center of the nucleus 2 can move, so the cooperation of the movable protrusion 31 and the movable recess enables the nucleus 2 to move in the radial direction and rotate around the central axis relative to the lower end plate 3, and in addition, the cooperation of the movable protrusion 31 and the movable recess limits the excessive movement and rotation of the nucleus 2, preventing the nucleus 2 from being detached from the lower end plate 3 under excessive pressure.

[0032] As Figures 3 to 8 shown, in some optional embodiments, the lower surface of the upper end plate 1 and the upper surface of the nucleus 2 form a ball-and-socket joint.

[0033] Further, the lower surface of the upper end plate 1 is concavely provided with a spherical recess 11, the upper surface of the nucleus 2 is convexly provided with a spherical dome 22, and the ball-and-socket joint is composed of the spherical recess 11 and the spherical dome 22, so that the upper end plate 1 can move freely in six directions of flexion / extension, left / right bending and left / right rotation relative to the nucleus 2.

[0034] If the lower surface of the upper endplate 1 and the upper surface of the nucleus pulposus 2 are both planar, the upper endplate 1 can only move in the radial direction and rotate around the central axis relative to the nucleus pulposus 2, so that the upper endplate 1 cannot freely move relative to the nucleus pulposus 2. Therefore, a ball-and-socket joint is formed between the lower surface of the upper endplate 1 and the upper surface of the nucleus pulposus 2. Since the ball-and-socket joint is formed by the spherical groove 11 and the spherical dome 22, the upper endplate 1 can freely move in six directions, i.e., flexion / extension, left / right bending, and left / right rotation, relative to the nucleus pulposus 2.

[0035] As shown in FIG. 1, Figure 1 and FIG. 2, Figure 2 in some optional embodiments, the upper surface of the upper endplate 1 is provided with an arc-shaped protrusion 12, and the upper surface of the upper endplate 1 is provided with a plurality of upper inverted teeth 13 symmetrically or asymmetrically distributed around the arc-shaped protrusion 12.

[0036] The shape of the upper inverted teeth 13 includes but is not limited to wedge-shaped, conical, triangular pyramid-shaped, etc. The upper inverted teeth 13 are connected and fixed with the vertebrae, and at the same time, the arc-shaped protrusion 12 can better cooperate with the concave anatomical surface of the vertebral body, achieving good stability effect.

[0037] As shown in FIG. 1, Figure 1 and FIG. 2,

[0038] By providing a plurality of upper clamping grooves 14 on the outer side wall of the upper endplate 1, the corresponding clamping tool can be matched, and the surgical installation of the upper endplate 1 is facilitated.

[0039] As shown in FIG. 1, Figure 2 , Figure 4 , Figure 6 , Figure 8 in some optional embodiments, the lower surface of the lower endplate 3 is provided with an elliptical protrusion 32, and the lower surface of the lower endplate 3 is provided with a plurality of lower inverted teeth 33 symmetrically or asymmetrically distributed around the elliptical protrusion 32.

[0040] The shape of the lower inverted teeth 33 includes but is not limited to wedge-shaped, conical, triangular pyramid-shaped, etc. The lower inverted teeth 33 are connected and fixed with the vertebrae, and at the same time, the elliptical protrusion 32 can better cooperate with the concave anatomical surface of the vertebral body, achieving good stability effect.

[0041] As shown in FIG. 1, Figure 1 in some optional embodiments, the outer side wall of the lower endplate 3 is provided with a plurality of lower clamping grooves 34.

[0042] By providing a plurality of lower clamping grooves 34 on the outer side wall of the lower endplate 3, the corresponding clamping tool can be matched, and the surgical installation of the lower endplate 3 is facilitated.

[0043] As Figure 3 With Figure 4 As shown in Embodiment 1, the movable convex part 31 is located at the center of the upper surface of the lower endplate 3, the movable convex part 31 includes a transverse convex part 311 and a longitudinal convex part 312, the center of the transverse convex part 311 intersects with the center of the longitudinal convex part 312 to form a cross-shaped movable convex part 31; the movable concave groove 21 is located at the center of the lower surface of the nucleus pulposus 2, the movable concave groove 21 includes a transverse concave groove 211 and a longitudinal concave groove 212, the center of the transverse concave groove 211 intersects with the center of the longitudinal concave groove 212 to form a cross-shaped movable concave groove 21; the transverse convex part 311 is embedded in the transverse concave groove 211, and the longitudinal convex part 312 is embedded in the longitudinal concave groove 212.

[0044] The transverse convex part 311 of the movable convex part 31 can move along the transverse direction in the transverse concave groove 211, and the longitudinal convex part 312 of the movable convex part 31 can move along the longitudinal direction in the longitudinal concave groove 212; at the same time, when the transverse convex part 311 moves along the transverse direction, the longitudinal convex part 312 can also move along the transverse direction, and when the longitudinal convex part 312 moves along the longitudinal direction, the transverse convex part 311 can also move along the longitudinal direction. In addition, the transverse convex part 311 and the longitudinal convex part 312 can rotate around the center axis with the center intersection position as the axis.

[0045] As Figure 5 With Figure 6 As shown in Embodiment 2, the movable convex part 31 is located at the center of the upper surface of the lower endplate 3, the movable convex part 31 is in the shape of a straight line, and the movable concave groove 21 is located at the center of the lower surface of the nucleus pulposus 2, the movable concave groove 21 is in the shape of a straight line.

[0046] The movable convex part 31 in the shape of a straight line can move in the radial direction and rotate around the center axis in the movable concave groove 21 in the shape of a straight line. The angle range of the rotation around the center axis is related to the width of the movable concave groove 21, the wider the width of the movable concave groove 21, the greater the angle of the rotation of the movable convex part 31 around the center axis, and the specific angle can be set according to the actual needs of the customer.

[0047] As Figure 7 With Figure 8 As shown in Embodiment 3, the movable convex part 31 is located at the center of the upper surface of the lower endplate 3, the movable convex part 31 is in the shape of an elliptical cylinder, and the movable concave groove 21 is located at the center of the lower surface of the nucleus pulposus 2, the movable concave groove 21 is in the shape of an elliptical cylinder.

[0048] The movable convex part 31 in the shape of a cylinder can move in the radial direction and rotate around the center axis in the movable concave groove 21 in the shape of a cylinder. The angle range of the rotation around the center axis is related to the width of the movable concave groove 21, the wider the width of the movable concave groove 21, the greater the angle of the rotation of the movable convex part 31 around the center axis, and the specific angle can be set according to the actual needs of the customer.

[0049] The above is only the preferred embodiment of the present application, and does not limit the technical scope of the present application in any way. Therefore, any slight modification, equivalent change and modification of the above embodiment according to the technical essence of the present application still belongs to the scope of the technical solution of the present application.

Claims

1. An artificial intervertebral disc prosthesis comprising an upper endplate, a nucleus and a lower endplate, characterized in that, The lower surface of the upper end plate and the upper surface of the nucleus pulposus are fitted, the lower surface of the nucleus pulposus is fitted with the upper surface of the lower end plate, the lower surface of the nucleus pulposus is provided with a movable groove, the upper surface of the lower end plate is provided with a movable convex part, the movable convex part is embedded in the movable groove, and the side wall of the movable convex part has a gap with the inner side wall of the movable groove. The cooperation of the movable convex part and the movable groove enables the radial movement and rotation of the nucleus pulposus relative to the lower end plate.

2. The artificial disc prosthesis of claim 1, wherein, The movable convex part is located at the center of the upper surface of the lower end plate, and the movable convex part includes a transverse convex part and a longitudinal convex part. The center of the transverse convex part intersects with the center of the longitudinal convex part to form a cross-shaped movable convex part. The movable groove is located at the center of the lower surface of the nucleus pulposus, and the movable groove includes a transverse groove and a longitudinal groove. The center of the transverse groove intersects with the center of the longitudinal groove to form a cross-shaped movable groove. The transverse convex part is embedded in the transverse groove, and the longitudinal convex part is embedded in the longitudinal groove.

3. The artificial disc prosthesis of claim 1 wherein, The movable convex part is located at the center of the upper surface of the lower end plate, and the movable convex part is a single-shaped convex part. The movable groove is located at the center of the lower surface of the nucleus pulposus, and the movable groove is a single-shaped groove.

4. The artificial disc prosthesis of claim 1 wherein, The movable convex part is located at the center of the upper surface of the lower end plate, and the movable convex part is an elliptical cylindrical convex part. The movable groove is located at the center of the lower surface of the nucleus pulposus, and the movable groove is an elliptical cylindrical groove.

5. The artificial disc prosthesis of claim 1 wherein, The lower surface of the upper end plate and the upper surface of the nucleus pulposus form a ball-and-socket joint.

6. The artificial disc prosthesis of claim 5, wherein, The lower surface of the upper end plate is concave and provided with a spherical concave groove, and the upper surface of the nucleus pulposus is convex and provided with a spherical dome. The ball-and-socket joint is formed by the spherical concave groove and the spherical dome. The ball-and-socket joint enables the upper end plate to move freely in six directions, i.e., forward flexion / rear extension, left / right lateral bending, and left / right rotation, relative to the nucleus pulposus.

7. The artificial disc prosthesis of claim 1 wherein, The upper surface of the upper end plate is provided with an arc-shaped protrusion, and the upper surface of the upper end plate is provided with a plurality of upper inverted teeth symmetrically or asymmetrically distributed around the arc-shaped protrusion.

8. The artificial disc prosthesis of claim 1 wherein, The outer side wall of the upper end plate is provided with a plurality of upper clamping grooves.

9. The artificial disc prosthesis of claim 1 wherein, The lower surface of the lower end plate is provided with an elliptical convex part, and the lower surface of the lower end plate is provided with a plurality of lower inverted teeth symmetrically or asymmetrically distributed around the elliptical convex part.

10. The artificial disc prosthesis of claim 1 wherein, The outer side wall of the lower end plate is provided with a plurality of lower clamping grooves.

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