Pedicle screw connector and spinal stabilization device

Abstract

This invention discloses a rod-end pedicle screw connector and a spinal stabilization device. The connector includes: a first retaining member having a cylindrical cavity, a main receiving groove, and a compression cavity; a second retaining member disposed in the cylindrical cavity and fixed to the rod-shaped member; a main pressure cap screwed into the upper wall of the cylindrical cavity; a first auxiliary pressure cap for applying pressure to the second retaining member; a covering member disposed in the compression cavity for clamping the ball head of the screw; a force transmission member disposed between the covering member and the main pressure cap for transmitting the pressure applied by the main pressure cap to the covering member; an elastic member disposed in the cylindrical cavity having a first connecting end and a second connecting end, which allows the two connecting ends to move closer or further apart and allows the first connecting end to swing relative to the second connecting end in any direction through elastic deformation; the first connecting end is fixedly connected to the second retaining member, and the second connecting end is fixedly connected to the first retaining member or the force transmission member.

Description

Technical Field

[0001] This invention relates to a device for correcting and stabilizing the spine, and more particularly to a rod-end pedicle screw connector and a spinal stabilization device. Background Technology

[0002] Spinal stabilization devices (systems) are used to correct deformities of the entire spine or parts of the spine caused by bone diseases or injuries (such as spinal curvature caused by osteoarthritis or ankylosing spondylitis, or fractures of several vertebrae in the spine caused by trauma) to stabilize them in a normal shape and physiological curve.

[0003] A spinal stabilization device (system) typically includes: a rod-shaped component, a pedicle screw for screwing into the posterior side of the vertebra, and a connector for connecting the pedicle screw to the rod-shaped component; the connector acts as a connecting medium component so that the pedicle screw screw, screwed into the posterior side of the vertebra, is connected to the rod-shaped component, thereby the rod-shaped component provides support for the spine.

[0004] In traditional spinal stabilization devices (systems), the connector is fixedly attached to a rod-like component. Specifically, the connector includes a retaining component and a pressure cap. The tail of the pedicle screw is formed at the bottom of the retaining component, which has a radially penetrating receiving groove extending downwards from the top. The rod-like component is received by the receiving groove, and the pressure cap is screwed into the retaining component to press the rod-like component, thereby fixing the connector to the rod-like component. Because the rod-like component is usually a rigid rod and the connection between the connector and the rod-like component is a fixed connection, this type of spinal stabilization device (system) provides essentially rigid support to the spine. This type of spinal stabilization device (system) can be called a rigid spinal stabilization device (system). By fixing the rod-like component to the connector, the rigid spinal stabilization device (system) can completely inhibit vertebral mobility. Therefore, the rigid spinal stabilization device (system) has significant advantages in correcting the posture of problematic vertebrae and reconstructing the physiological curve of the spinal segment where the problematic vertebra is located.

[0005] However, when correcting a problem vertebra, this rigid spinal stabilization device (system) can have the following adverse effects on the normal vertebrae adjacent to the problem vertebra at the distal end: On the one hand, if the normal vertebra adjacent to the problem vertebra at the distal end is also supported by the rod-like component, the mobility of the adjacent normal vertebra may be completely suppressed for a long time, resulting in a loss of some mobility. This means that the mobility of the vertebra may take a long time to recover after the stabilization device (system) is removed. On the other hand, since the mobility of all vertebrae supported by the stabilization device (system) is completely suppressed, the lost mobility of all supported vertebrae is mainly compensated by the intervertebral discs of the vertebrae adjacent to the supported distal vertebrae. This may lead to damage or failure of the intervertebral discs corresponding to the adjacent vertebrae, especially when there are a large number of vertebrae that are completely suppressed, the possibility of damage or failure of the intervertebral discs corresponding to the vertebrae adjacent to the distal vertebrae is even greater.

[0006] To overcome the aforementioned shortcomings of spinal stabilization devices (systems) in correcting the spine, the prior art provides a dynamic spinal stabilization device (system) that allows a certain degree of mobility in a segment of the vertebra (e.g., a normal vertebra adjacent to the terminal problem vertebra) while being supported by a rod-like component. To this end, the prior art improves upon the conventional coupling by adding an upper and lower mating component within the retaining component. The upper and lower mating components slide against each other via a cylindrical or spherical surface. A pressure cap is used to press the rod-like component against the upper mating component. The sliding engagement between the upper and lower mating components allows the coupling to pivot relative to the rod-like component in the sagittal plane, thereby providing a certain degree of mobility for the vertebra.

[0007] However, the aforementioned stabilizing device (system) still has the following problems:

[0008] 1. After the spinal stabilization system is implanted, the driving ability of the muscles near the spine decreases, which makes it difficult for the muscles to reposition the vertebrae after flexion and extension in the sagittal plane. The aforementioned coupling, which uses cylindrical or spherical surfaces, only allows the vertebrae to rotate and does not contribute to the repositioning of the vertebrae after flexion and extension. In fact, the friction between the two coupling components inhibits the repositioning of the vertebrae, which can easily lead to muscle damage.

[0009] 2. In some couplings that allow for spatial angle adjustment of pedicle screws, locking of the pedicle screw after adjustment relies on the pressure applied by two mating parts to the sleeve covering the ball head of the screw. This results in: if locking the screw is required, the pressure between the two mating parts increases, leading to increased friction between them, which in turn significantly increases the damping that inhibits vertebral movement, or even completely inhibits the range of motion. If the pressure is reduced to decrease the damping that inhibits vertebral movement, the screw may not be able to be locked stably.

[0010] To address the problems of the aforementioned dynamic spinal devices, the applicant's prior patent application (patent publication number: CN117717404A) provides a bone screw connector and a spinal stabilization system. The connector includes a first retaining component and a second retaining component. The second retaining component is disposed within the first retaining component and has a main body and a connecting portion located below the main body. A rod-shaped component is received by a second receiving groove on the main body and fixed to the main body by a second pressure cap. A first pressure cap is screwed onto the cylindrical cavity of the first retaining component above the second pressure cap. An elastic portion is provided between the main body and the connecting portion. The sex component consists of two elastic curved plates symmetrically arranged about a vertical plane (coronal plane) orthogonal to the sagittal plane. The middle of the two elastic curved plates has an inwardly curved convex region. When the first pressure cap is screwed against the second pressure cap, causing the rod-shaped component to abut against the bottom of the first receiving groove of the first retaining component, the rod-shaped component is fixed and the elastic curved plates are elastically compressed. When the first pressure cap is screwed in the opposite direction, the elastic curved plates return to their original position and the rod-shaped component moves upward, thereby allowing the rod-shaped component to pivot under the elastic damping provided by the elastic curved plates. This allows the corresponding vertebra to pitch (pivot) under elastic damping, and after pitching, active reduction is achieved by the elastic reduction of the elastic curved plates. In addition, a partition member with a push plate is provided below the joint of the second retaining member. The push plate is screwed into the first retaining member. By screwing the push plate, pressure can be applied to the covering member used to hold the ball head of the bone screw, thereby avoiding the bone screw being locked by applying pressure to the covering member through the joint of the second retaining member. Therefore, when the rod member is in the released state that allows pivoting, the bone screw will not be unable to be stably locked because the rod member is in the released state.

[0011] However, the aforementioned bone screw fasteners and spinal stabilization systems have the following problems when in use:

[0012] 1. The elastic part composed of two symmetrically arranged elastic curved plates can only meet the requirements of vertebral pivoting in the sagittal plane, but it is difficult to meet the requirements of vertebral pivoting in the coronal and transverse planes.

[0013] 2. The internal stress generated by the deformation of the elastic plate caused by vertebral movement is concentrated in a small area of ​​inward convexity, which can easily lead to elastic deformation failure and elastic repositioning failure in this area.

[0014] 3. When it is necessary to adjust the angle of the bone screw relative to the connector, the second retaining component and the rod-shaped component in the first retaining component must be removed before the angle of the bone screw can be adjusted by rotating the loosening push plate. Therefore, the operation of adjusting the angle of the bone screw is complicated and affects the original correction shape. Summary of the Invention

[0015] To address the aforementioned technical problems in the prior art, the present invention provides a rod-end pedicle screw connector and a spinal stabilization device.

[0016] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0017] A rod-end pedicle screw connector, comprising:

[0018] The first retaining member has a cylindrical cavity and a main receiving groove, and a compression cavity located below the cylindrical cavity, the main receiving groove being for receiving the rod-shaped member and having a width greater than the diameter of the rod-shaped member;

[0019] The second retaining component is disposed in the columnar cavity and fixed to the rod-shaped component;

[0020] The main pressure cap screws into the upper cavity wall of the cylindrical cavity;

[0021] The first pressure cap is used to apply pressure to the second retaining member;

[0022] A covering component, disposed within the compression chamber and defining a spherical cavity for covering the ball head of a pedicle screw, wherein pressure is applied to the covering component, causing the compression chamber to force the spherical cavity to clamp the ball head; wherein:

[0023] A force transmission component is disposed between the covering component and the main pressure cap, the force transmission component being used to transmit the pressure applied by the main pressure cap to the covering component;

[0024] The cylindrical cavity is provided with an elastic component, which is configured to have a first connecting end and a second connecting end in the axial direction. Through elastic deformation, the first connecting end is allowed to move closer or further away from each other and the first connecting end is allowed to swing relative to the second connecting end in any direction.

[0025] The first connecting end is fixedly connected to the second retaining component, and the second connecting end is fixedly connected to the first retaining component or the force transmitting component.

[0026] Preferably, the elastic component includes an outer cylinder section and an inner cylinder section formed by bending an elastic wall radially outward or radially inward, and integrally connected at the bottom by a bent section. The upper end of the inner cylinder section serves as the first connecting end, and the upper end of the outer cylinder section serves as the second connecting end.

[0027] Preferably, the lower middle part of the inner cylinder section, the lower middle part of the outer cylinder section, and the bending section are formed into elastic deformation sections by reducing their thickness.

[0028] Preferably, circumferentially arranged gaps are provided in the area where the elastic deformation segment is located.

[0029] Preferably, the force transmission component includes a base and two opposing driven arms formed on the base, the rod-shaped component passing through a notch between the two driven arms; the driven arms extend axially upward within the columnar cavity, passing through the annular gap between the outer peripheral surface of the first retaining component and the cavity wall of the columnar cavity, and extending to the bottom of the main pressure cap.

[0030] Preferably, the main pressure cap has a through threaded hole in the middle region, and the first auxiliary pressure cap is screwed into the threaded hole. The second retaining member is pressed against the first auxiliary pressure cap by screwing on the first auxiliary pressure cap.

[0031] Preferably, the first connecting end of the elastic component is fixedly connected to the bottom of the second retaining component, and the second connecting end of the elastic component is connected to the force transmitting component.

[0032] Preferably, the bottom of the second retaining component is configured as a cylindrical joint, the first joint end is sleeved on the cylindrical joint, a circumferentially extending positioning groove is provided on the lower side wall of the driven arm, a stepped surface is formed above the positioning groove, a flange plate is formed on the second joint end, the flange plate slides into the positioning groove from one side of the notch, and a fastener is screwed into the stepped surface and passes through the flange plate to fix the flange plate.

[0033] Preferably, a secondary receiving groove is provided at the top of the second retaining member, the secondary receiving groove being circumferentially opposite to the main receiving groove, the secondary receiving groove having a cylindrical groove bottom that mates with the outer circumferential surface of the rod-shaped member, the secondary receiving groove being used to receive the rod-shaped member, and a second secondary pressure cap is screwed onto the top of the second retaining member for pressing against the rod-shaped member, the first secondary pressure cap being used to press against the second secondary pressure cap.

[0034] Preferably, the first sub-cap is equipped with circumferentially arranged support columns that can elastically extend and elastically retract to the bottom of the first sub-cap.

[0035] The present invention also discloses a spinal stabilization system, comprising: a rod-shaped component and a pedicle screw, wherein the spinal stabilization system further comprises the aforementioned rod-end pedicle screw connector, the rod-end pedicle screw connector being coupled to the rod-shaped component, and the pedicle screw being coupled to the bottom of the rod-end pedicle screw connector.

[0036] Compared with the prior art, the beneficial effects of the rod-end pedicle screw connector and spinal stabilization device disclosed in this invention are:

[0037] 1. The connector provided by the present invention allows the normal vertebrae adjacent to the terminal problem vertebrae to have a certain degree of mobility in the sagittal, coronal and transverse planes under elastic damping by configuring elastic components with elastic extension and elastic swing characteristics, thereby enabling the spinal stabilization device to form specific and excellent dynamic support for the normal vertebrae adjacent to the terminal problem vertebrae.

[0038] 2. The elastic component provided by the present invention has excellent resistance to stress concentration and elastic fatigue because it has an inner cylinder section, an outer cylinder section, a curved section and two joint ends located on the same side, which are formed by the bending structure of the elastic wall. Therefore, the spinal stabilization system provided by the present invention still has a better dynamic support effect on the vertebrae after long-term and frequent activities of the terminal vertebrae.

[0039] 3. The connector provided by the present invention can lock the bone screw without disassembling the rod-shaped component and other related components by adding a force transmission component and a first auxiliary pressure cap screwed into the main pressure cap, and can switch the fixed / release state of the rod-shaped component while ensuring that the bone screw is always in the locked state.

[0040] 4. Other advantages of the present invention are described directly or implicitly in the specific embodiments of the specification.

[0041] The overview of various implementations or examples of the technology described in this invention is not a complete disclosure of the full scope or all features of the disclosed technology. Attached Figure Description

[0042] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with or without letter suffixes may indicate different instances of similar parts. The drawings generally illustrate various embodiments by way of example rather than limitation and, together with the description and claims, serve to explain embodiments of the invention. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0043] Figure 1 This is a three-dimensional structural diagram of the spinal stabilization device provided in an embodiment of the present invention.

[0044] Figure 2 An exploded perspective view of the connector provided for an embodiment of the present invention.

[0045] Figure 3 A perspective sectional view of the connector provided for an embodiment of the present invention.

[0046] Figure 4This is a view showing the assembly relationship between the second retaining component, the force transmitting component, and the elastic component.

[0047] Figure 5 This is a view showing the assembly relationship between the force transmission component and the elastic component.

[0048] Figure 6 This is a schematic diagram of the three-dimensional structure of the elastic component.

[0049] Figure 7 This is a front sectional view of the elastic component.

[0050] Figure 8 A state view of the spinal stabilization device provided in an embodiment of the present invention during spinal calibration.

[0051] Figure label:

[0052] 10-First retaining component; 11-Columnar cavity; 12-Main receiving groove; 121-V-shaped groove bottom; 13-Extrusion cavity; 14-Positioning groove; 20-Second retaining component; 21-Secondary receiving groove; 30-Covering component; 31-Elastic arm; 32-Spherical cavity; 41-Main pressure cap; 411-Driven operating groove; 412-Threaded hole; 42-First secondary pressure cap; 421-Driven operating groove; 422-Support column; 43-Second secondary pressure cap; 431-Driven operating groove; 50-Force transmission component; 51-Base ; 511-Embedding groove; 512-Stepped surface; 52-Driven arm; 53-Positioning protrusion; 54-Notch; 55-Operating hole; 60-Elastic component; 61-First connecting end; 62-Second connecting end; 621-Flange plate; 63-Elastic wall; 64-Bending section; 65-Gap; 66-Elastic deformation section; 67-Inner cylinder section; 68-Outer cylinder section; 100-Connector; 200-Bone nail; 201-Ball head; 202-Driven operating groove; 300-Rod-shaped component; 400-Normal vertebra. Detailed Implementation

[0053] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0054] To keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of known functions and known components are omitted.

[0055] like Figure 1 and combined Figure 8 As shown, embodiments of the present invention disclose a connector 100 and a spinal stabilization device including the connector 100. The spinal stabilization device further includes a pedicle screw (hereinafter referred to as a bone screw 200) for screwing into the posterior side of the vertebra of the spine and a rod-shaped component 300 for supporting, correcting and stabilizing.

[0056] In the spinal stabilization device disclosed in this invention, at least at the end of its rod-shaped component 300, a connector 100 provided by this invention is arranged. This connector 100 is used to connect bone screws 200, screwed into normal vertebrae 400 (one or more normal vertebrae 400) adjacent to the problem vertebra at the end, to the rod-shaped component 300. This allows the rod-shaped component 300 to provide a certain degree of support to the normal vertebrae 400 while also allowing for a certain degree of mobility. The connector 100 provided by this invention is particularly suitable for placement at positions corresponding to vertebrae in the cervical spine segment (C1-C7 segment), thereby providing sufficient in-plane mobility for the vertebrae in that segment. The connector 100 provided by this invention can also be placed in other sections of the rod-shaped component 300 corresponding to the problem vertebra, whereby the connector 100 is adjusted to be fixed to the rod-shaped component 300, thereby providing rigid support to the problem vertebra.

[0057] like Figures 2 to 7 As shown, the connector 100 provided by the present invention includes: a first retaining member 10, a second retaining member 20, a covering member 30, an elastic member 60, a force transmitting member 50, a main pressure cap 41, a first auxiliary pressure cap 42, and a second auxiliary pressure cap 43.

[0058] like Figure 2 and Figure 3 and combined Figure 1As shown, an axially extending cylindrical cavity 11 is formed from the top of the first retaining member 10, and a compression cavity 13 penetrating the bottom of the first retaining member 10 is formed from the bottom of the cylindrical cavity 11. A retaining wall (or cylindrical cavity 11 surrounded by the retaining wall) is defined between the cavity wall of the cylindrical cavity 11 and the outer peripheral surface of the first retaining member 10. An axially extending main receiving groove 12 is formed from the top of the first retaining member 10, and the main receiving groove 12 radially penetrates the retaining wall of the first retaining member 10. Thus, the main receiving groove 12 is formed on the solid retaining wall and has two opposing grooves in the circumferential direction. The bottom of the main receiving groove 12 is machined into a V-shaped groove bottom 121 surrounded by two inclined surfaces. In spinal correction surgery, The rod-shaped member 300 simultaneously enters both main receiving slots 12 from the top of the first retaining member 10 and is received by both main receiving slots 12. By applying pressure to the rod-shaped member 300 within the section between the two main receiving slots 12, the cylindrical surface of the rod-shaped member 300 simultaneously abuts against the V-shaped groove bottoms 121 of the two main receiving slots 12, thus fixing the rod-shaped member 300 to the first retaining member 10. By removing and reducing the pressure on the rod-shaped member 300, the rod-shaped member 300 is moved away from the V-shaped groove bottoms 121, allowing the rod-shaped member 300 to be released. This allows the first retaining member 10 (relative to the rod-shaped member 300) to move at least within the plane containing the two main receiving slots 12, i.e., within the sagittal plane. In this invention, the width of the main receiving slots 12 is greater than the diameter of the rod-shaped member 300, thereby allowing the first retaining member 10 to move within any plane, including the sagittal plane, coronal plane, and cross-sectional plane, after the rod-shaped member 300 is released.

[0059] like Figure 3 and Figure 4 and combined Figure 2As shown, the outer peripheral surface of the second retaining member 20 is cylindrical, and the second retaining member 20 is located in the cylindrical cavity 11 of the first retaining member 10. A secondary receiving groove 21 is formed from the top of the second retaining member 20, which radially penetrates the second retaining member 20. Furthermore, the secondary receiving groove 21 is circumferentially opposite to the two main receiving grooves 12, so that the rod-shaped member 300 enters the secondary receiving groove 21 at the same time as entering the main receiving groove 12, and is thus also received by the secondary receiving groove 21. The bottom of the second receiving groove is configured as a cylindrical surface with the same diameter as the rod-shaped member 300. The upper outer peripheral surface of the second retaining member 20 is machined with external threads, and the edge of the second auxiliary cover 43 has a sidewall with internal threads. The second auxiliary cover 43 is screwed onto the top of the second retaining member 20 through the engagement of the internal and external threads. Furthermore, the bottom center of the second auxiliary cover 43 has a boss. When the second auxiliary cover 43 is screwed down relative to the second retaining member 20, the boss presses against the top of the rod-shaped member 300, causing the lower part of the rod-shaped member 300 to abut against the bottom of the secondary receiving groove 21, thereby fixing the rod-shaped member 300 to the second retaining member 20. The regular hexagonal (octagonal) structure machined on the edge of the second auxiliary cover 43 for screwing by a force-applying tool can also be as follows: Figure 4 The hexagonal driven operating groove 431 shown is machined in the central region of the upper surface of the second sub-cap 43. In this invention, a certain annular gap is provided between the cylindrical surface enclosed by the second retaining member 20 (including the radial dimension occupied by the second sub-cap 43) and the cylindrical cavity 11 of the first retaining member 10, so as to allow sufficient movement of the first retaining member 10 relative to the rod-shaped member 300 and the second retaining member 20.

[0060] like Figure 3 and Figure 4 As shown, the covering component 30 is placed in the compression chamber 13 below the cylindrical cavity 11 of the first retaining component 10. The covering component 30 has a flat cylindrical main body at the top and a covering portion integrally formed at the bottom of the main body. The covering portion includes a plurality of circumferentially arranged elastic arms 31, which form a spherical cavity 32 with an inlet at the bottom. The ball head 201 of the tail of the bone screw 200 enters the spherical cavity 32 through the inlet. The lower part of the compression chamber 13 is formed with a conical surface. Thus, when pressure is applied to the main body of the covering component 30 and the covering component 30 moves downward, the conical surface of the compression chamber 13 applies pressure to all the elastic arms 31, causing the elastic arms 31 to clamp the ball head 201, thereby increasing the damping of the angle adjustment of the bone screw 200 and completely locking the bone screw 200.

[0061] like Figure 2 and Figure 3As shown, an internal thread is machined on the upper cavity wall of the cylindrical cavity 11 of the first retaining member 10, and an external thread is machined on the outer peripheral surface of the main pressure cap 41. Thus, the main pressure cap 41 can be screwed into the upper part of the cylindrical cavity 11 from the top of the first retaining member 10. A driven operating groove 411 is disposed in the middle region of the upper part of the main pressure cap 41 for a force-applying tool to screw the main pressure cap 41. The force-applying tool screws the main pressure cap 41 by acting on the driven operating groove 411.

[0062] like Figure 2 and Figure 3As shown, a force transmission member 50 is provided between the main pressure cap 41 and the main body of the covering member 30 in the axial section. The force transmission member 50 is used to transmit the power applied by the main pressure cap 41 to the covering member 30 so that the covering member 30 moves downward, thereby increasing the damping of the bone screw 200 and locking the bone screw 200. Specifically, the force transmission component 50 includes a base 51 for engaging with the main body of the covering component 30 and driven arms 52 extending axially upward from the base 51 to the bottom of the main pressure cap 41. The driven arms 52 include two arms, and two opposing notches 54 are defined between the two driven arms 52. The notches 54 are opposite to the main receiving groove 12, so that the rod-shaped component 300 can pass through the force transmission component 50 without interfering with the movement of the force transmission component 50. The width of the notch 54 should be greater than the diameter of the rod-shaped component 300. For example, the width of the notch 54 is equal to or greater than the width of the main receiving groove 12 to avoid the notch 54 affecting the pivoting or movement of the rod-shaped component 300 in the coronal plane and cross-section. The two driven arms 52 pass through the annular gap between the second retaining member 20 and the cylindrical cavity 11. Therefore, the axial movement of the driven arms 52 is not interfered with by the passing member. Furthermore, by properly configuring the annular gap so that the first retaining member 10 has sufficient movement relative to the second retaining member 20, the driven arms 52 will not interfere with the second retaining member 20. When the main pressure cap 41 is screwed down, the main pressure cap 41 drives the driven arms 52 down, causing the base 51 to press against the covering member 30 and down, thereby increasing the damping and locking damping of the bone screw 200. Preferably, a positioning groove 14 is provided on the cavity wall of the cylindrical cavity 11, and a positioning protrusion 53 is provided on the outer surface of the driven arm 52. When the second retaining member 20 is inserted into the cylindrical cavity 11 from the top of the first retaining member 10, the positioning protrusion 53 on the driven arm 52 slides into the positioning groove 14, thus restricting the rotation of the force transmission member 50 relative to the first retaining member 10, thereby restricting the rotation of the first retaining member 10 relative to the bone screw 200 when the bone screw 200 is locked. Operating holes 55 are provided on all components between the spherical cavity 32 of the covering member 30 and the top of the first retaining member 10, allowing the force-applying tool to reach the ball head 201 of the bone screw 200 from the top of the first retaining member 10. Thus, before engaging the rod-shaped member 300, the force-applying tool acts on the driven operating groove 202 of the ball head 201 of the bone screw 200 through the operating holes 55 for screwing the bone screw 200.

[0063] like Figure 2 and Figure 3As shown, the bottom of the driven operating groove 411 of the main pressure cover 41 is provided with a threaded hole 412, which passes through the bottom of the main pressure cover 41. The first auxiliary pressure cover 42 is screwed into the threaded hole 412. The upper part of the first auxiliary pressure cover 42 is provided with a driven operating groove 421 for a force-applying tool to screw the first auxiliary pressure cover 42. By screwing the first auxiliary pressure cover 42 down, the lower part of the first auxiliary pressure cover 42 presses against the second auxiliary pressure cover 43, so that the second retaining member 20 drives the rod-shaped member 300 down and abuts the rod-shaped member 300 against the V-shaped groove bottom 121 of the main receiving groove 12, thereby fixing the rod-shaped member 300 to the first retaining member 10. Since the bone screw 200 can be completely locked by screwing on the main pressure cap 41, and the rod-shaped component 300 is fixed to the first retaining component 10 by screwing on the first auxiliary pressure cap 42, the rod-shaped component 300 can provide rigid support to the corresponding vertebra through the connector 100 provided by the present invention. By screwing on the first auxiliary pressure cap 42 in the opposite direction, the rod-shaped component 300 is released, thereby allowing the connector 100 to move relative to the rod-shaped component 300, thereby allowing the vertebra to move relative to the rod-shaped component 300, and thus allowing the vertebra to have a certain degree of mobility. Furthermore, since the width of the main receiving groove 12 is greater than the width of the rod-shaped component 300, the vertebra is allowed to move in any plane, including the sagittal plane, the coronal plane, and the transverse plane. Preferably, the force-applying tool is configured with an outer sleeve and an inner sleeve having a driven operating groove 411 for acting on the main cap 41 and a driven operating groove 421 for acting on the first auxiliary cap 42, respectively. The outer sleeve and the inner sleeve are driven independently of each other, so that the main cap 41 and the first auxiliary cap 42 can be screwed from the top of the connector 100.

[0064] like Figure 6 and Figure 7 and combined Figure 3As shown, the key to this invention is that it provides an elastic component 60 whose structure and deformation characteristics differ from those of an elastic part formed by two symmetrically arranged elastic bent plates. Specifically, the elastic component 60 includes an inner cylinder section 67, an outer cylinder section 68, and a bent section 64 integrally connected between the outer cylinder section 68 and the inner cylinder section 67 in terms of its external structure. The inner cylinder section 67, the outer cylinder section 68, and the bent section 64 of the elastic component 60 are formed by a wall made of elastic material (which may be called an elastic wall 63) bent in the reverse direction in the radial direction inward (in this case, the part formed after the reverse direction inward bending is the inner cylinder section 67) or bent in the reverse direction outward in the radial direction (in this case, the part formed after the reverse direction outward bending is the outer cylinder section 68). The ends of the inner cylinder section 67 and the outer cylinder section 68 are both upward. The end of the inner cylinder section 67 may be called the first connecting end 61, and the end of the outer cylinder section 68 may be called the second connecting end 62. Preferably, the lower middle part of the inner cylinder section 67, the lower middle part of the outer cylinder section 68, and the curved section 64 are formed into an elastic deformation section 66 by reducing the thickness, and a plurality of circumferentially arranged slits 65 are provided in the area where the elastic deformation section 66 is located. Preferably, the first joint end 61 is higher than the second joint end 62.

[0065] The elastic component 60 with the above-mentioned structural features has the following deformation characteristics:

[0066] 1. When pressure is applied to the first joint end 61 while the second joint end 62 is fixed, the first joint end 61 moves downward, which is equivalent to the elastic member 60 being elastically compressed. However, the internal stress characteristics of the elastic member 60 during elastic compression deformation are different from those of the elastic portion formed by the elastic bending plate. During the compression process of the elastic member 60 formed by the elastic bending plate, the internal stress is always mainly concentrated in the area where the inner convex portion of the elastic bending plate is located. However, during the compression process of the elastic member 60 of the present invention, the bottom bending section 64 changes and is not fixed (inherent) from a fixed section. The elastic wall 63 is responsible for bending. Specifically, as the elastic member 60 is compressed, the previously unbent elastic wall 63 forming the inner cylinder section 67 begins to bend with the degree of compression. Therefore, different degrees of compression are handled by different sections of the elastic wall 63, so the internal stress caused by bending during compression will not occur in the fixed section. Similarly, when a tensile force is applied to the first joint end 61, this is equivalent to the elastic member 60 being elastically stretched. Different degrees of stretching are handled by different sections of the elastic wall 63, so the internal stress caused by bending during stretching will not only occur in the fixed section. Therefore, during the elastic expansion and contraction of the elastic member 60 provided by the present invention, the stress caused by deformation will not concentrate and will always occur in a certain fixed section, so that the internal stress is dispersed by the longer section of the elastic wall 63, thereby delaying the elastic deformation failure of the elastic member 60.

[0067] 2. When the second joint end 62 is fixed, the inner cylinder section 67 can swing in any direction in a manner that provides elastic damping and can automatically elastically reset. Furthermore, during the swing, the internal stress can be dispersed to a certain extent by the elastic wall 63, thereby delaying the elastic deformation failure of the elastic component 60.

[0068] 3. By reducing the thickness of the lower middle part of the inner cylinder section 67, the lower middle part of the outer cylinder section 68, and the bending section 64, the elastic deformation only occurs in the section with reduced thickness, which is beneficial to predefine the deformation section of the elastic component 60 in the design stage.

[0069] 4. By opening numerous circumferentially arranged slits 65 in the area where the elastic deformation section 66 is located, the inner cylinder section 67 is allowed to elastically twist and automatically reset when the second joint end 62 is fixed.

[0070] As can be seen from the above, the elastic component 60 not only allows the first connecting end 61 to elastically extend and retract, elastically swing in any direction, and elastically torsion, but also ensures that the internal stress will not concentrate in a small area during elastic extension and retraction and elastic swing, thus having the ability to disperse internal stress.

[0071] like Figure 4 and Figure 5 and combined Figure 3 As shown, the aforementioned elastic component 60 is installed below the second retaining component 20, and the first connecting end 61 is fixedly connected to the second retaining component 20, while the second connecting end 62 is fixedly connected to the force transmission component 50. Specifically, a cylindrical connecting portion is machined at the bottom of the second retaining component 20, and the first connecting end 61 is fitted onto the cylindrical connecting portion. Multiple screws arranged circumferentially, radially penetrating the cylindrical wall of the first connecting end 61 and screwed into the cylindrical connecting portion, are used to fix the first connecting end 61 to the bottom of the second retaining component 20. A circumferentially extending embedding groove 511 is formed on the inner sidewall of the lower part of each driven arm 52, extending to the notch 54. A stepped surface 512 is formed above the embedding groove 511, and two flanges are configured on the second connecting end 62. When installing the elastic member 60, the flange plate 621 is first aligned with the notch 54, so that the flange plate 621 can be moved from the top of the notch 54 to the bottom of the notch 54 and flush with the groove 511. Then, the elastic member 60 is rotated so that the flange plate 621 slides into the groove 511 from one side. Then, a plurality of fasteners arranged circumferentially are screwed into the stepped surface 512 and the screws pass through the flange plate 621 to fix the flange plate 621, thereby fixing the second connecting end 62 to the force transmission member 50.

[0072] The advantages of using the elastic component 60 with the above structure in a spinal stabilization device are described below.

[0073] Regarding the rigid support of the problematic vertebra: the connector 100 can be used to provide rigid support for the problematic vertebra. Specifically, the connector 100 can be arranged on the section of the rod-shaped member 300 corresponding to the problematic vertebra. By screwing down the first auxiliary pressure cap 42, it presses against the second retaining member 20 and moves it down. The first engagement end 61 of the elastic member 60 moves down in accordance with the second retaining member 20, and the elastic member 60 is elastically compressed. The rod-shaped member 300 abuts against the V-shaped groove bottom 121 of the two main receiving grooves 12 as the second retaining member 20 moves down. The rod-shaped member 300 is fixed to the first retaining member 10, thereby restricting the movement of the first retaining member 10 (i.e., the connector 100) relative to the rod-shaped member 300, thereby further restricting the movement of the problematic vertebra relative to the rod-shaped member 300, and realizing the rigid support of the rod-shaped member 300 for the problematic vertebra.

[0074] Regarding dynamic support of a normal vertebra 400 adjacent to the terminal problem vertebra: the connector 100 is particularly suitable for providing dynamic support to a normal vertebra 400 adjacent to the terminal problem vertebra. Specifically, the connector 100 is arranged on the end section of the rod-shaped member 300 corresponding to the normal vertebra 400. At this time, by reversing the rotation of the first auxiliary pressure cap 42 upwards, the pressure on the second retaining member 20 is released. The elastic member 60 switches from an elastic compression state to an elastic reset state due to the release of pressure. The second retaining member 20 moves upwards, causing the rod-shaped member 300 to move away from the bottom of the main receiving groove 12. This ensures that the first auxiliary pressure cap 42 remains at a certain distance from the second retaining member 20 even after the second retaining member 20 moves upward. Since the width of the main receiving groove 12 is greater than the width of the rod-shaped member 300, and the rod-shaped member 300 is at a certain distance from the bottom of the main receiving groove 12 and the first auxiliary pressure cap 42, the first retaining member 10 and the rod-shaped member 300 form a movable connection, thereby allowing the first retaining member 10 to move relative to the rod-shaped member 300. In this way, the rod-shaped member 300 provides dynamic support to the vertebra through the elastic member 60, thereby allowing the vertebra to move under the elastic damping provided by the elastic member 60.

[0075] It should be noted that in this invention, the so-called dynamic support does not mean that the movement of the vertebrae is completely unrestricted, but rather that the vertebrae are allowed to move under the elastic damping provided by the elastic component 60. Therefore, the movement of the vertebrae is inhibited by the elastic damping, which helps to prevent the lost mobility of the problematic vertebrae from being compensated mainly by the adjacent normal vertebrae 400, thereby protecting the adjacent vertebrae.

[0076] In terms of dynamic support, the second retaining member 20 is restricted in its movement due to its fixation to the rod-shaped member 300. Therefore, the vertebra is allowed to move with the first retaining member 10. Based on the elastic deformation characteristics of the elastic member 60 provided by the present invention, the coupling 100 provided by the present invention, by providing the aforementioned elastic member 60, not only allows the first retaining member 10 to move axially under elastic damping and automatically elastically reset, but also allows the first retaining member 10 to swing radially and twist under elastic damping and automatically reset. Figure 8 As shown, because the first retaining member 10 is allowed to move along its axial direction under elastic damping and to swing in any direction in a plane perpendicular to the axial direction of the first retaining member 10, the vertebra is allowed to pitch in the sagittal plane (since the spinal stabilizing device is located in the sagittal plane and on the posterior side of the vertebra, the first retaining member 10 needs a certain amount of axial movement to accommodate the pitch of the vertebra); because the first retaining member 10 is allowed to swing in any direction in a plane perpendicular to the axial direction of the first retaining member 10 under elastic damping, the vertebra is allowed to twist in the transverse plane; because the first retaining member 10 is allowed to twist in a plane perpendicular to the axial direction of the first retaining member 10 under elastic damping, the vertebra is allowed to swing in the coronal plane.

[0077] In some preferred configurations, a support column 422 is mounted on the first sub-cap 42, which is circumferentially arranged and can elastically extend and retract at the bottom of the first sub-cap 42. When the first sub-cap 42 is screwed down to abut against the second sub-cap 43 at the top of the second retaining member 20, the support column 422 retracts into the first sub-cap 42. When the first sub-cap 42 is screwed up in the opposite direction to release the second retaining member 20, the support column 422 extends out of the bottom of the first sub-cap 42 and abuts against the second sub-cap 43, thereby keeping the second retaining member 20 at a certain distance from the first sub-cap 42. Thus, by providing pre-tightening pressure to the second retaining member 20, it is beneficial to prevent interference between the rod-shaped member 300 and the first sub-cap 42 when the first retaining member 10 moves relative to the rod-shaped member 300.

[0078] Furthermore, although exemplary embodiments have been described in this invention, their scope includes any and all embodiments based on the invention that have equivalent elements, modifications, omissions, combinations (e.g., schemes involving intersections of various embodiments), adaptations, or alterations. Elements in the claims will be interpreted broadly based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of this application, and such examples will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered illustrative only, and the true scope and spirit are indicated by the full scope of the following claims and their equivalents.

[0079] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. Other embodiments may be used by those skilled in the art upon reading the above description. Furthermore, in the above detailed description, various features may be grouped together to simplify the invention. This should not be construed as an intention that a disclosed feature, which is not claimed, is necessary for any claim. Rather, the subject matter of the invention may be less than all the features of the particular disclosed embodiment. Thus, the following claims are incorporated herein by reference as examples or embodiments, wherein each claim is independently considered as a separate embodiment, and these embodiments are contemplated as being possible in various combinations or arrangements. The scope of the invention should be determined by reference to the appended claims and the full scope of their equivalents.

[0080] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A rod-end pedicle screw connector, characterized in that, include: The first retaining member has a cylindrical cavity and a main receiving groove, and a compression cavity located below the cylindrical cavity, the main receiving groove being for receiving the rod-shaped member and having a width greater than the diameter of the rod-shaped member; The second retaining component is disposed in the columnar cavity and fixed to the rod-shaped component; The main pressure cap screws into the upper cavity wall of the cylindrical cavity; The first pressure cap is used to apply pressure to the second retaining member; A covering component, disposed within the compression chamber and defining a spherical cavity for covering the ball head of the pedicle screw, wherein pressure is applied to the covering component, causing the compression chamber to force the spherical cavity to clamp the ball head; wherein: A force transmission component is disposed between the covering component and the main pressure cap, the force transmission component being used to transmit the pressure applied by the main pressure cap to the covering component; The cylindrical cavity is provided with an elastic component, which is configured to have a first connecting end and a second connecting end in the axial direction. Through elastic deformation, the first connecting end is allowed to move closer or further away from each other and the first connecting end is allowed to swing relative to the second connecting end in any direction. The first connecting end is fixedly connected to the second retaining component, and the second connecting end is fixedly connected to the first retaining component or the force transmitting component; The elastic component includes an outer cylinder section and an inner cylinder section formed by bending an elastic wall radially outward or radially inward, and integrally connected at the bottom by a bent section. The upper end of the inner cylinder section serves as the first connecting end, and the upper end of the outer cylinder section serves as the second connecting end. The lower middle part of the inner cylinder section, the lower middle part of the outer cylinder section, and the bending section are formed into elastic deformation sections by reducing their thickness; The area where the elastic deformation section is located has circumferentially arranged gaps. The force transmission component includes a base and two opposing driven arms formed on the base. The rod-shaped component passes through a notch between the two driven arms. The driven arms extend axially upward within the columnar cavity, passing through the annular gap between the outer peripheral surface of the first retaining component and the cavity wall of the columnar cavity, and extend to the bottom of the main pressure cap.

2. The rod-end pedicle screw connector according to claim 1, characterized in that, The main pressure cap has a through threaded hole in the middle area, and the first auxiliary pressure cap is screwed into the threaded hole. The first auxiliary pressure cap is screwed on to press against the second retaining component.

3. The rod-end pedicle screw connector according to claim 1, characterized in that, The first connecting end of the elastic component is fixedly connected to the bottom of the second retaining component, and the second connecting end of the elastic component is connected to the force transmitting component.

4. The rod-end pedicle screw connector according to claim 3, characterized in that, The bottom of the second retaining component is configured as a cylindrical joint, and the first joint end is sleeved on the cylindrical joint. A circumferentially extending positioning groove is provided on the lower side wall of the driven arm. A stepped surface is formed above the positioning groove. A flange plate is formed on the second joint end. The flange plate slides into the positioning groove from one side of the notch. Fasteners are screwed into the stepped surface and pass through the flange plate to fix the flange plate.

5. The rod-end pedicle screw connector according to claim 1, characterized in that, A secondary receiving groove is provided at the top of the second retaining member. The secondary receiving groove is circumferentially opposite to the main receiving groove. The secondary receiving groove has a cylindrical groove bottom that mates with the outer circumferential surface of the rod-shaped member. The secondary receiving groove is used to receive the rod-shaped member. A second secondary pressure cap is screwed onto the top of the second retaining member for pressing against the rod-shaped member. The first secondary pressure cap is used to press against the second secondary pressure cap.

6. The rod-end pedicle screw connector according to claim 1, characterized in that, The first sub-cap is equipped with circumferentially arranged support columns that can elastically extend and elastically retract to the bottom of the first sub-cap.

7. A spinal stabilization system, comprising: The rod-shaped component and the pedicle screw are characterized in that the spinal stabilization system further includes a rod-end pedicle screw connector as described in any one of claims 1 to 6, the rod-end pedicle screw connector being attached to the rod-shaped component, and the pedicle screw being attached to the bottom of the rod-end pedicle screw connector.

Images