CN115399925A - Adjustable center of rotation intervertebral disc prosthesis - Google Patents

Abstract

The invention relates to the technical field of intelligent medical instruments, and discloses an intervertebral disc prosthesis with an adjustable center of rotation. The present invention includes an upper endplate, a lower endplate and a nucleus pulposus prosthesis arranged between the upper endplate and the lower endplate, the nucleus pulposus prosthesis includes a first prosthesis and a second prosthesis arranged up and down, the first The prosthesis is provided with a ball head, and the second prosthesis is provided with a spherical groove suitable for the ball head. The first prosthesis and the second prosthesis are interlocked and can rotate relative to each other to meet the flexibility of movement after being implanted in the human body. property; between the upper end plate and the lower end plate, there is a matching space for the whole nucleus pulposus prosthesis to move in the vertical direction and the horizontal direction. The present invention adjusts the position of the nucleus pulposus prosthesis through the driving mechanism, so that the Work in harmony with the anatomy of the cervical motion functional unit, thereby reducing the non-physiological stress and strain in the bone and soft tissue structure, and can maximize the reconstruction of the physiological rotation center of the motion segment, improve the efficacy of CDR surgery, and reduce the occurrence of adverse events.

Description

Adjustable center of rotation intervertebral disc prosthesis

technical field

The invention relates to the technical field of intelligent medical instruments, in particular to an intervertebral disc prosthesis with an adjustable center of rotation.

Background technique

At present, cervical disc replacement (CDR) has been proven to be an effective surgical procedure for the treatment of cervical spondylotic radiculopathy and cervical spondylotic myelopathy. The purpose of CDR is to restore the normal biomechanical function of cervical spondylosis. Compared with the classic anterior cervical decompression and fusion (ACDF), the advantages of CDR are that it can preserve the motor function of the operated segment and delay the occurrence of adjacent segment degeneration. The design concept of CDR is not only to preserve the quantity of segmental motion, but also to be able to simulate the natural nature of motion and ensure the quality of motion. At present, the range of motion of the intervertebral disc (ROM) is usually used clinically to evaluate the mobility of the artificial intervertebral disc, which reflects the change of the amount of motion, and the center of rotation (COR) can reflect the change of the kinematic properties. In the study of spinal kinematics, COR is usually used to describe the motion of the upper vertebral body relative to the lower vertebral body, that is, the motion of the spinal functional unit (FSU).

The rotation center of the existing intervertebral disc prosthesis cannot be adjusted, so it cannot fully match the rotation center of the functional segment of the spine under physiological conditions, resulting in non-physiological effects on the hook vertebral joints, facet joints and soft tissues after the intervertebral disc prosthesis is implanted. The collision, load, etc., accelerate degeneration; and this mismatch may cause relative movement of the implant-bone interface during daily activities, resulting in adverse events such as prosthesis subsidence and displacement, osteolysis, and even prosthesis prolapse. In addition, the center of rotation of the cervical spine of different patients and different surgical segments of the same patient are different, and the center of rotation of the existing prosthesis design cannot adapt to patients with different cervical spine characteristics and the center of rotation of different segments.

Contents of the invention

The technical problem solved by the present invention is to provide an intervertebral disc prosthesis with adjustable rotation center, which can adjust the position of the rotation center.

The technical solution adopted by the present invention to solve the technical problem is: the intervertebral disc prosthesis with adjustable center of rotation, including the upper endplate, the lower endplate and the nucleus pulposus prosthesis arranged between the upper endplate and the lower endplate, the nucleus pulposus The prosthesis includes a first prosthesis and a second prosthesis arranged up and down, the first prosthesis is provided with a spherical head, the second prosthesis is provided with a spherical groove adapted to the ball head, the first prosthesis and the The second prosthesis is interlocked and can rotate relative to each other; a fitting space for the nucleus pulposus prosthesis to move vertically and horizontally as a whole is provided between the upper endplate and the lower endplate, and a drive The driving mechanism for the overall movement of the nucleus pulposus prosthesis.

Further, the side of the upper endplate close to the nucleus pulposus prosthesis and the side of the lower endplate close to the prosthesis are both provided with installation grooves; the driving mechanism includes a horizontal movement mechanism, and the horizontal movement mechanism includes a horizontal movement mechanism arranged in the first horizontal direction The first slide bar and the second slide bar arranged in the second horizontal direction, the first horizontal direction and the second horizontal direction are perpendicular to each other, the first slide bar and the second slide bar are fixed in the installation groove On the inner wall, the first slider and the second slider are slidably connected with a first slider; the nucleus prosthesis is slidably connected with a connecting rod, and one end of the connecting rod is fixedly connected with the first slider through a connecting piece , the connecting rod includes a first connecting rod parallel to the first sliding rod, and a second connecting rod parallel to the second sliding rod; the driving mechanism further includes a first driving device for driving the first sliding block to slide.

Preferably, the drive mechanism includes a lifting mechanism, the lifting mechanism includes a third slide bar vertically arranged on the first slide block, one end of the third slide bar is fixedly arranged on the first slide block, and the third slide bar A second slider is slidably connected to the rod, and both the first connecting rod and the second connecting rod are fixedly connected to the second slider, and the drive mechanism further includes a second driving device for driving the second slider to slide.

More preferably, a first distance sensor is provided on the nucleus pulposus prosthesis, and a second distance sensor is provided on both the first slider and the second slider.

More preferably, the first slide bar, the second slide bar and the third slide bar are all screw rods, and the first slide block and the second slide block are provided with corresponding threaded through holes.

Further: the connecting end of the third sliding rod is provided with a snap ring, and the first slider is provided with a snap slot matching the snap ring, and the snap ring is snap-fitted in the snap slot; the The end of the third slide bar is provided with a shaft hole along its axial direction, and the side of the first slide block close to the third slide bar is provided with a rotating shaft adapted to the shaft hole.

Further, there are two first sliding rods and two second sliding rods, and the two first sliding rods and the two second sliding rods are arranged in a rectangular shape.

Further, the nucleus pulposus prosthesis is provided with permanent magnets near the side of the installation groove of the upper endplate and the side of the installation groove of the lower endplate, and several magnets for magnetically driving the nucleus pulposus are arranged in the installation groove. Inductive coil for horizontal and vertical movement of the prosthesis.

Further, the driving mechanism includes a first driving mechanism and a second driving mechanism, the first driving mechanism is used to drive the lower part of the nucleus pulposus prosthesis to move; the second driving mechanism is used to drive the upper part of the nucleus pulposus prosthesis to move.

The beneficial effects of the present invention are:

1. In the present invention, the first prosthesis and the second prosthesis are interlocked with each other and can be rotated relative to each other to meet the flexibility of movement after being implanted in the human body. The overall position of the nucleus pulposus prosthesis is adjusted by the driving mechanism to make it rotate The center can be adjusted to the adaptive position under the corresponding physiological state, so that the anatomical coordination between the prosthesis and the cervical motion functional unit can reduce the non-physiological stress and strain in the bone and soft tissue structure, and can maximize the physiological reconstruction of the motion segment Rotation center to improve the curative effect of CDR surgery and reduce the occurrence of adverse events;

2. The moving rail system of the nucleus pulposus prosthesis is established through mechanisms such as slide rods and sliders, and the nucleus pulposus prosthesis can be moved under the action of the driving mechanism; Next, the adjustment of the position can be realized by manual twisting, which is convenient for adjustment; another driving method of the present invention uses magnetic force to drive the movement of the nucleus pulposus prosthesis, and controls the pulposus prosthesis by magnetic attraction or repulsion by controlling the current of the inductance coil at different positions. The movement of nuclear prosthesis is suitable for small precision devices such as intervertebral disc prosthesis, and it is more convenient to adjust the center of rotation by cooperating with automatic control components.

Description of drawings

Fig. 1 is a structural representation of the present invention;

2 is a schematic diagram of the drive structure in the lower endplate;

Figure 3 is a schematic structural view of the lower endplate;

Fig. 4 is a schematic diagram of the connection structure between the third slide bar and the first slide block;

Fig. 5 is a schematic diagram of the arrangement of the inductance coil in the installation slot;

Marked in the figure: upper endplate 1, lower endplate 2, first prosthesis 3, second prosthesis 4, first slider 5, second slider 6, first slider 7, third slider 8 , the second slider 9.

Detailed ways

In the description of the present invention, it should be noted that the terminology of the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the product of the invention is used, or is Orientation or positional relationship commonly understood by those skilled in the art, such terms are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation , and therefore cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance. Herein, "parallel", "perpendicular" and the like are not strictly restricted in the sense of mathematics and/or geometry, but also include errors understandable by those skilled in the art and allowed in manufacturing or use.

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the adjustable center of rotation intervertebral disc prosthesis of the present invention comprises an upper endplate 1, a lower endplate 2 and a nucleus pulposus prosthesis arranged between the upper endplate 1 and the lower endplate 2, the pulp The nuclear prosthesis includes a first prosthesis 3 and a second prosthesis 4 arranged up and down, the first prosthesis 3 is provided with a ball head, and the second prosthesis 4 is provided with a spherical groove adapted to the ball head, The first prosthesis 3 and the second prosthesis 4 are interlocked and can rotate relative to each other, imitating the physiological actions of the intervertebral disc, such as forward flexion, backward extension, left and right lateral flexion, rotation and their coupled movements, etc., ensuring implantation Flexibility of rear human body movement; specifically, the second prosthesis 4 is set one and is set in the lower end plate 2, the first prosthesis 3 is set above the second prosthesis 4 and is set in the upper end plate 1, both of them pass through the ball head part and the spherical groove and rotate fit; the second prosthesis 4 can also be provided with two and respectively arranged in the upper endplate 1 and the lower endplate 2, and the upper and lower parts of the first prosthesis 4 are provided with ball heads The first prosthesis 4 is rotatably connected between the upper and lower second prosthesis 4 . In order to make the rotation center of the nucleus pulposus prosthesis adapt to patients with different cervical vertebra characteristics and the rotation center of different segments, a driving mechanism that can adjust the position of the nucleus pulposus prosthesis is also provided. In the groove, a matching space is formed between the two installation grooves of the lower endplate 2 and the upper endplate 1. The driving mechanism includes a first driving mechanism and a second driving mechanism. The first driving mechanism is arranged near the lower endplate of the nucleus pulposus. In the installation groove on one side of the end plate 2, it is used to drive the lower part of the nucleus pulposus prosthesis to move; the second driving mechanism is arranged in the installation groove on the side of the nucleus pulposus prosthesis close to the upper end plate 1, and is used to drive the nucleus pulposus prosthesis The upper body moves. The first driving mechanism and the second driving mechanism simultaneously drive the lower part and the upper part of the nucleus pulposus prosthesis, and the overall movement of the nucleus pulposus prosthesis is performed synchronously.

Further, the driving mechanism includes a lifting mechanism and a horizontal moving mechanism, and the horizontal moving mechanism includes a first slide bar 5 arranged in a first horizontal direction and a second slide bar 6 arranged in a second horizontal direction, and the first horizontal direction and the second horizontal direction are perpendicular to each other, the first sliding bar 5 and the second sliding bar 6 are slidably connected with the first sliding block 7, so that the position adjustment of the nucleus pulposus prosthesis can be realized in the same horizontal plane, and the first driving The first slide bar 5 and the second slide bar 6 of the mechanism are fixedly arranged in the lower endplate 2, and the first slide bar 5 and the second slide bar 6 of the second drive mechanism are fixedly arranged in the upper endplate 1, The driving device used to drive the sliding of the first slider 7 can adopt a miniature linear motor, a stepper motor, etc., and of course it can also be directly adjusted manually; the nucleus pulposus prosthesis is slidably connected to the connecting rod, and one end of the connecting rod is connected to The part is fixedly connected with the first slider 7, and the connecting rods include a first connecting rod parallel to the first sliding rod 5 and a second connecting rod parallel to the second sliding rod 6. When the nucleus pulposus prosthesis is adjusted in position, The connecting rod plays a supporting role.

Further, in order to improve the stability of the nucleus pulposus prosthesis during movement, the first sliding rod 5 and the second sliding rod 6 are provided with two, the two first sliding rods 5 and the two second sliding rods The second slide bar 6 is surrounded by a rectangle and is then connected with the second slide block 9 on the third slide bar 8 by two connecting bars forming a "ten" shape. It should be understood that the two connecting rods are arranged horizontally, and the relative positions of the connecting rods on the prosthesis are set so that one is above and the other is below, so as to avoid movement interference.

Furthermore, in this embodiment, the elevating mechanism is set in linkage with the horizontal moving mechanism, and the elevating mechanism includes a third sliding rod 8 vertically arranged on the first slider 7, and one end of the third sliding rod 8 is fixedly arranged on the On the first slider 7 , a second slider 9 is slidably connected to the third slider 8 , and both the first connecting rod and the second connecting rod are fixedly connected to the second slider 9 . The third slide bar 8 is used as a connecting piece to connect the vertically moving second slide block 9 with the horizontally move first slide block 7 .

When it is necessary to adjust the center of rotation of the nucleus pulposus prosthesis, the first slide bar 5 or the second slide bar 6 at the bottom and top of the nucleus pulposus prosthesis is rotated clockwise or counterclockwise at the same time, and the first slide block 7 is on the corresponding slide Sliding on the bar in the forward direction or in the opposite direction, the first slider 7 drives the whole nucleus pulposus prosthesis to adjust its position on the horizontal plane; at the same time, the plurality of third sliders 8 and the second slider 9 are rotated in the same direction. To realize the rising or falling action, the whole nucleus pulposus prosthesis is adjusted in the vertical direction between the two installation grooves.

Furthermore, in order to realize the control of adjusting the distance, a first distance sensor is provided on the nucleus pulposus prosthesis, and a second distance sensor is provided on both the first slider and the second slider. The first distance sensor is used to test the relative position between the nucleus pulposus prosthesis and the inner wall of the installation groove, so as to monitor the distance it moves, and the second distance sensor is used to test the distance between the slider and the inner wall of the upper end plate 1 or between the slider and the lower The distance in the sliding direction between the inner walls of the end plates 2 further monitors and controls the movement of the nucleus pulposus prosthesis and improves the control accuracy of the rotation center position.

Furthermore, in order to control the start and stop of the slide block conveniently, as shown in Figure 2 and Figure 3, the first slide bar 5, the second slide bar 6 and the third slide bar 8 are all screw rods, the first slide block 7, Corresponding threaded through holes are provided in the second slider 9, and the movement of the slider is controlled by the rotation of the screw mandrel; the first slider 5 and the second slider 6 are rotatably connected to the inner wall of the upper endplate 1 and the lower endplate 2 inner walls. When the position of the nucleus pulposus prosthesis needs to be adjusted, the position adjustment of the first slide block 7 and the second slide block 9 can be realized by rotating the corresponding slide bar. The driving device used to drive the rotation of the first slide bar 5 and the second slide bar 6 can adopt a micro-drive motor, a stepper motor, etc., and of course it can also be directly adjusted manually. Preferably, as shown in Figure 4, a snap ring is provided at the connecting end of the third slide bar 8, and a snap slot matching the snap ring is arranged in the first slider 7, and the snap ring is snap-fitted on the snap ring. In the connecting groove; the end of the third sliding rod 8 is provided with a shaft hole along its axial direction, and the first sliding block 7 is provided with a rotating shaft adapted to the shaft hole on the side close to the third sliding rod 8 . The third sliding bar 8 is fixed through the above-mentioned limiting structure, and at the same time, the rotation of the third sliding bar 8 is not affected to move the second sliding block 9 up and down.

The driving device in the present invention is not limited to be driven by the above-mentioned mechanical power device, as long as it can achieve the purpose of driving the nucleus pulposus prosthesis to adjust its position between the upper endplate and the lower endplate, in the present invention The driving device can also be driven by magnetic force, and it works according to the principle that the same sex attracts and the opposite sex repels each other. The top and bottom of the nucleus prosthesis are fixed with permanent magnets, and several inductance coils are arranged in the installation groove, as shown in Figure 5. The circle in the figure shows the axial section of the inductance coil, and the magnetic poles of the permanent magnet correspond to the inductance coil When the magnetic poles are set when energized, the axial direction of the inductance coil is set in the horizontal direction or the vertical direction.

Specifically, inductance coils are respectively arranged on the first horizontal direction and the second horizontal direction of the inner wall of the installation groove, the axial direction of the inductance coil is in the same direction as the first horizontal direction and the second horizontal direction, and the inductance coils in the same horizontal direction When the inductance coil is energized, the magnetic poles at the end of the inductance coil on opposite sides are different or the same magnetic pole, and an inductance coil is also arranged on the bottom surface of the installation groove along the vertical direction. The axial direction of the inductance coil is located in the vertical direction, and the horizontal Or the permanent magnet poles in the vertical direction are opposite to the induction coil poles in this direction. It should be understood that the magnetic pole at the end can be changed by adjusting the current direction of the inductance coil at different positions, and the attraction or repulsion force can also be controlled by adjusting the current on-off or current magnitude of the inductance coil at different positions. Preferably, a current control device and a control system can also be provided. The current control device and the distance sensor are both electrically connected to the control system, and the position adjustment of the nucleus pulposus prosthesis can be operated more conveniently through the control system.

Use magnetic force to drive the movement of the nucleus pulposus prosthesis. When the horizontal position needs to be adjusted, the inductance coils in the first horizontal direction and the second horizontal direction are energized, and the bottom of the nucleus pulposus prosthesis and The top acts at the same time to make the whole move in the horizontal direction and adjust the position on the horizontal plane; when the position in the vertical direction needs to be adjusted, the inductance coil in the vertical direction is energized, and the inductance coil in the vertical direction is used to adjust the position. The magnetic poles act on the bottom and top of the nucleus pulposus prosthesis at the same time, so that the whole can be lifted in the vertical direction.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (9)

1. The intervertebral disc prosthesis with the adjustable rotation center comprises an upper end plate (1), a lower end plate (2) and a nucleus pulposus prosthesis arranged between the upper end plate (1) and the lower end plate (2), and is characterized in that: the nucleus pulposus prosthesis comprises a first prosthesis (3) and a second prosthesis (4) which are arranged up and down, wherein the first prosthesis (3) is provided with a bulb part, the second prosthesis (4) is provided with a spherical groove which is adaptive to the bulb part, and the first prosthesis (3) and the second prosthesis (4) are mutually buckled and can relatively rotate; a matching space for the whole nucleus pulposus prosthesis to move in the vertical direction and the horizontal direction is arranged between the upper end plate (1) and the lower end plate (2), and the device also comprises a driving mechanism for driving the whole nucleus pulposus prosthesis to move.

2. The center-of-rotation adjustable intervertebral disc prosthesis of claim 1, wherein: mounting grooves are formed in one side, close to the nucleus pulposus prosthesis, of the upper end plate (1) and one side, close to the nucleus pulposus prosthesis, of the lower end plate (2); the driving mechanism comprises a horizontal moving mechanism, the horizontal moving mechanism comprises a first sliding rod (5) arranged in a first horizontal direction and a second sliding rod (6) arranged in a second horizontal direction, the first horizontal direction is perpendicular to the second horizontal direction, the first sliding rod (5) and the second sliding rod (6) are fixedly arranged on the inner wall of the mounting groove, and a first sliding block (7) is connected to the first sliding rod (5) and the second sliding rod (6) in a sliding manner; the nucleus pulposus prosthesis is connected with a connecting rod in a sliding manner, one end of the connecting rod is fixedly connected with a first sliding block (7) through a connecting piece, and the connecting rod comprises a first connecting rod parallel to the first sliding rod (5) and a second connecting rod parallel to the second sliding rod (6); the driving mechanism also comprises a first driving device for driving the first sliding block (7) to slide.

3. The adjustable center of rotation intervertebral disc prosthesis of claim 2, wherein: actuating mechanism includes elevating system, and elevating system includes vertical third slide bar (8) of setting on first slider (7), and a third slide bar (8) tip is fixed to be set up on first slider (7), sliding connection has second slider (9) on third slide bar (8), head rod, second connecting rod all with second slider (9) fixed connection, actuating mechanism is still including being used for driving the gliding second drive arrangement of second slider (9).

4. The adjustable center of rotation intervertebral disc prosthesis of claim 3, wherein: a first distance sensor is disposed on the nucleus prosthesis.

5. The adjustable center of rotation intervertebral disc prosthesis of claim 3, wherein: the first sliding rod (5), the second sliding rod (6) and the third sliding rod (8) are screw rods, and corresponding threaded through holes are formed in the first sliding block (7) and the second sliding block (9).

6. The center of rotation adjustable intervertebral disc prosthesis of claim 5, wherein: a clamping ring is arranged at the connecting end of the third sliding rod (8), a clamping groove matched with the clamping ring is arranged in the first sliding block (7), and the clamping ring is clamped in the clamping groove; the end part of the third slide bar (8) is provided with a shaft hole along the axial direction, and one side of the first slide block (7) close to the third slide bar (8) is provided with a rotating shaft matched with the shaft hole.

7. The adjustable center of rotation intervertebral disc prosthesis of claim 2, wherein: the first sliding rod (5) and the second sliding rod (6) are both provided with two sliding rods, and the first sliding rod (5) and the second sliding rod (6) are arranged in a rectangular shape in an enclosing mode.

8. Intervertebral disc prosthesis with adjustable centre of rotation according to claim 2, 3 or 4, characterised in that: permanent magnets are arranged on one side, close to the mounting groove of the upper end plate (1), of the nucleus pulposus prosthesis and on one side, close to the mounting groove of the lower end plate (2), of the nucleus pulposus prosthesis, and a plurality of inductance coils used for magnetically driving the horizontal movement and the lifting movement of the nucleus pulposus prosthesis are arranged in the mounting grooves.

9. The adjustable center of rotation intervertebral disc prosthesis of claim 1, wherein: the driving mechanism comprises a first driving mechanism and a second driving mechanism, and the first driving mechanism is used for driving the lower part of the nucleus pulposus prosthesis to move; the second drive mechanism is used to drive the movement of the upper portion of the nucleus prosthesis.

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