CN112220545B

CN112220545B - Spinal screw

Info

Publication number: CN112220545B
Application number: CN202011172761.7A
Authority: CN
Inventors: 郑淞元; 廖翚; 赵国军; 周鹏飞; 杨大诚
Original assignee: Tianjin Walkman Biomaterial Co ltd
Current assignee: Tianjin Walkman Biomaterial Co ltd
Priority date: 2020-10-28
Filing date: 2020-10-28
Publication date: 2023-12-26
Anticipated expiration: 2040-10-28
Also published as: CN112220545A

Abstract

The invention relates to a spinal screw comprising: the screw cap, the screw rod and the distance stopping module; the two sides of the screw cap are symmetrically provided with U-shaped openings, a distance stopping module is arranged below the U-shaped openings, the distance stopping module comprises a distance stopping block base, a spring and a distance stopping block, the distance stopping block is attached to a groove of a connecting rod clamped into the U-shaped openings, and the connecting rod is clamped; the outside of the screw rod is provided with a variable-pitch special-shaped thread, the screw rod is divided into a first part, a second part and a third part, the variable-pitch special-shaped thread of the first part is provided with a plurality of inverted teeth, the large diameter part of the variable-pitch special-shaped thread of the second part is provided with a waist-shaped through groove, a radial through hole is arranged in the waist-shaped through groove and communicated with a central hole of the screw rod, the small diameter part of the variable-pitch special-shaped thread of the second part is provided with a plurality of concave cone grooves, the head end of the third part is provided with a plurality of saw teeth, the center of the third part is provided with a cone counter bore, and two sides of the third part are provided with symmetrical notches. The invention has reasonable structure, convenient assembly, hidden bone cement injection channel and the inverted tooth for preventing nail withdrawal, and can reduce the occurrence of postoperative related complications.

Description

Spinal screw

Technical Field

The invention relates to the field of orthopedic medical instruments, in particular to a spinal screw.

Background

In modern orthopaedics operation, percutaneous internal fixation is a common internal fixation of the spine, and the application of the pedicle screw technology in spinal surgery is the most common, and has been widely applied to the treatment of lumbar vertebra slippage, spine fracture, chronic low back pain, spinal tumor and other diseases. Along with the popularization of the treatment means, a plurality of clinical bad symptoms, such as loosening of implanted screws, change of distance between connecting rods, screw withdrawal and the like, are easy to occur after operation. Thus increasing the pain and expense of the patient for the re-operation and increasing the trauma on the mind of the patient again, which requires higher requirements on the stability of the pedicle screw.

Disclosure of Invention

In order to solve the problems existing in the prior art, the invention aims to provide a spinal screw, a connecting rod is used, two sides of the connecting rod are provided with U-shaped openings, the screw cap is provided with a distance stopping module, the distance stopping module comprises a distance stopping block base, a spring and a distance stopping block, the top end of the distance stopping block is higher than the bottom of the U-shaped opening and is attached to a groove of the connecting rod, the connecting rod is prevented from moving after the connecting rod is implanted into a patient, the screw rod is provided with a variable-pitch abnormal-shaped thread outside the screw rod, the screw rod is divided into three parts, the variable-pitch abnormal-shaped thread of the first part is provided with a plurality of inverted teeth for increasing the stability of the screw, the variable-pitch abnormal-shaped thread of the second part is provided with a plurality of kidney-shaped through grooves with radial through holes, the radial through holes are communicated with the central holes of the screw rod for injecting bone cement, the third part is in a round table structure, two sides of the connecting rod are provided with gaps, and 12 irregularly-shaped saw teeth are distributed on the head parts, so that the connecting rod can be fully contacted with bone, the connecting rod is convenient to assemble, the spinal screw with a reasonable structure, the screw with a hidden bone cement injection channel and the reverse-shaped reverse tooth preventing the reverse tooth, and the occurrence of the relative pain can be better caused after the clinical compression effect can be prevented, and the clinical cone is achieved.

In order to achieve the above object, the present invention provides a spinal screw comprising:

the screw cap is of an internal thread structure, and U-shaped openings are symmetrically formed in two sides of the screw cap; the U-shaped opening is used for being clamped with an external connecting rod; the connecting rod is provided with two grooves;

the distance stopping modules are respectively positioned at the inner sides below the two U-shaped openings and comprise distance stopping block bases, springs and distance stopping blocks which are sequentially connected; the top end of the distance stopping block is higher than the bottom of the U-shaped opening and is used for being clamped with the groove of the connecting rod;

the screw rod is externally provided with a variable-pitch special-shaped thread, and the variable-pitch special-shaped thread comprises a first variable-pitch thread and a second variable-pitch thread which are adjacent; the screw shank further comprises:

a first portion connected to the nut, the first torque threads on the exterior of the first portion having a plurality of back teeth thereon;

the second part is connected with the first part, a plurality of waist-shaped through grooves are uniformly distributed at the large diameter of the variable-pitch special-shaped thread outside the second part, and a radial through hole is formed in the middle of each waist-shaped through groove; a plurality of concave cone grooves are distributed on the minor diameter of the variable-pitch special-shaped thread outside the second part;

the third part is in a truncated cone structure, the bottom end of the third part is connected with the second part, a plurality of saw teeth are distributed at the head end of the third part, a conical counter bore is formed in the center of the third part, and symmetrical notches are formed in two sides of the conical counter bore;

and the center hole is positioned at the center of the screw rod and penetrates through the first part and the second part, and the center hole is communicated with the radial through holes on the kidney-shaped through grooves.

Preferably, the crest width of the first variable pitch thread is 0.25mm, and the height difference between the crest of the first variable pitch thread and the crest of the second variable pitch thread is 0.34mm.

Preferably, the adjacent surfaces of the second pitch-variable thread and the first pitch-variable thread are first side surfaces, and the included angle between the first side surfaces and the crests of the first pitch-variable thread is 88 degrees.

Preferably, the number of the inverted teeth on the first variable pitch thread outside the first part is 99, and the interval between every two inverted teeth is 1mm.

Preferably, the minimum pitch of the variable pitch profiled thread is 1.5mm, and the maximum pitch of the variable pitch profiled thread is 3.5mm.

Preferably, the radial included angle between two adjacent concave conical grooves in the same radial plane is 10 degrees;

the internal angle of the concave conical groove ranges from 1 degree to 1.5 degrees.

Preferably, the number of the saw teeth at the head end of the third part is 12, and the tooth angle of the saw teeth ranges from 120 degrees to 121 degrees.

Preferably, the angle of the conical counter bore of the third part is 2 degrees, and the depth is 3.7mm.

Preferably, the height of the spring is 3mm, the diameter of the steel wire of the spring is 0.2mm, the pitch of the spring is 0.5mm, the curvature coefficient of the spring is 4, the height-to-diameter ratio of the spring is 3.8, the helix angle of the spring is 12.1 degrees, and the elasticity coefficient of the spring is 1.4.

The embodiment of the invention provides a spinal screw, which uses a connecting rod with U-shaped openings at two sides and with internal threads, wherein a distance stopping module is arranged in the screw cap, the distance stopping module comprises a distance stopping block base, a spring and a distance stopping block, the top end of the distance stopping block is higher than the bottom of the U-shaped opening and is attached to a groove of the connecting rod, the connecting rod is prevented from moving after being implanted into a patient, a variable-pitch abnormal-shaped thread is arranged outside a screw rod, the screw rod is divided into three parts, a plurality of inverted teeth are arranged on the variable-pitch abnormal-shaped thread of a first part and used for increasing the stability of the screw, a plurality of waist-shaped through grooves with radial through holes are arranged on the variable-pitch abnormal-shaped thread of a second part and are communicated with the central hole of the screw rod and are used for injecting bone cement, a third part is in a truncated cone structure, 12 irregularly-shaped saw teeth are distributed at the two sides, the head can be fully contacted with bone, the spinal column is reasonable in structure, the assembly is convenient, the performance is reliable, the hidden bone cement injection channel and the inverted teeth of the reverse screw are prevented from being deformed, and the related pain caused by the occurrence of the back cone is reduced, and the clinical pain can be prevented from happening after the compression is better.

Drawings

FIG. 1 is an elevation view of a spinal screw according to one embodiment of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a cross-sectional view of a dead-end module according to an embodiment of the present invention;

FIG. 4 is an enlarged view of a portion of FIG. 2 at B;

FIG. 5 is a left side view of a spinal screw according to one embodiment of the present invention;

FIG. 6 is an enlarged view of a portion of FIG. 5 at C;

FIG. 7 is a partial enlarged view at D of FIG. 5;

FIG. 8 is an enlarged view of a portion of FIG. 5 at E;

FIG. 9 is a schematic illustration of an assembly of a spinal screw and a connecting rod according to an embodiment of the present invention;

FIG. 10 is a schematic view of a connecting rod for use with spinal screws according to an embodiment of the present invention.

Detailed Description

The technical scheme of the invention is further described in detail through the drawings and the embodiments.

Fig. 1 is a front view of a spinal screw according to an embodiment of the present invention, fig. 2 is a cross-sectional view taken along line A-A in fig. 1, fig. 3 is a cross-sectional view of a distance stop module according to an embodiment of the present invention, and fig. 4 is an enlarged view of a portion of fig. 2 at B, as shown in fig. 1-4, the spinal screw comprising: a screw cap 1, a screw rod 2 and a distance stopping module 3.

The screw cap 1 has an internal thread structure, two sides of which are symmetrically provided with U-shaped openings 11, and the inner side of the screw cap 1 below each U-shaped opening is provided with a distance stopping module 3, wherein the distance stopping module 3 comprises: a stop base 31, a spring 32 and a stop 33. The spacing block base 31 is positioned at the lowest part, the spring 32 is positioned on the spacing block base 31, the spacing block 33 is positioned on the spring 32, and the top end of the spacing block 33 is higher than the bottom of the notch of the U-shaped opening 11. The main parameters of the spring 32 are: the height of the spring 32 is 3mm, the diameter of the steel wire of the spring 32 is 0.2mm, the pitch of the spring 32 is 0.5mm, the curvature coefficient of the spring 32 is 4, the aspect ratio of the spring 32 is 3.8, the helix angle of the spring 32 is 12.1 degrees, and the elasticity coefficient of the spring 32 is 1.4.

The screw rod 2 comprises a first part 22, a second part 23 and a third part 24 which are sequentially connected, the first part 22 is connected with the screw cap 1, the outer part of the screw rod 2 is provided with a variable-pitch special-shaped thread 21, and the variable-pitch special-shaped thread 21 comprises a first variable-pitch thread 211 and a second variable-pitch thread 212 which are adjacent. The pitch of the variable pitch profiled thread 21 increases gradually from the outside of the first portion 22 through the outside of the second portion 23 to the outside of the third portion 24, the minimum pitch of the variable pitch profiled thread 21 being 1.5mm and the maximum pitch being 3.5mm.

Wherein the width of the crests of the first-gauge thread 211 is 0.25mm, and the difference in height between the crests of the first-gauge thread and the crests of the second-gauge thread 212 is 0.34mm; the adjacent flanks of the first and second pitch-varying threads 211, 212 are first flanks that are angled at 88 ° from the crests of the first pitch-varying thread 211.

The screw shaft 2 has a central hole 25 in the center, the central hole 25 penetrating the centers of the first and second parts 22, 23 for placing bone cement.

Fig. 5 is a left side view of a spinal screw according to an embodiment of the present invention, fig. 6 is a partial enlarged view of a portion C of fig. 5, fig. 7 is a partial enlarged view of a portion D of fig. 5, and fig. 8 is a partial enlarged view of a portion E of fig. 5, as shown in fig. 5 to 8, 99 inverted teeth 221 are distributed on a surface of a first variable pitch thread 211 outside a first portion 22 of a screw rod 2, a space between every two inverted teeth 211 is 1mm, and stability of the spinal screw is further increased by using the inverted teeth 211, so as to prevent the occurrence of screw withdrawal after the spinal screw is implanted into a human body.

A plurality of kidney-shaped through grooves 231 are uniformly distributed at the large diameter of the variable pitch special-shaped thread 21 outside the second part 23 of the screw rod 2, and a radial through hole 232 is arranged in the middle of each kidney-shaped through groove 231 and is communicated with the central hole 25, so that bone cement is injected into the central hole 25.

A plurality of concave conical grooves 233 are distributed at the minor diameter of the variable pitch profiled thread 21 outside the second portion 23 of the screw shaft 2, the radial included angle between two adjacent concave conical grooves 233 in the same radial plane being 10 °, the internal angle of the concave conical grooves 233 being in the range of 1 ° to 1.5 °.

The third part 24 of the screw rod 2 is of a truncated cone structure, the bottom end is connected with the second part 23, 12 irregularly-shaped saw teeth 241 are distributed at the head end and can fully contact with bone, the range of tooth angles of the saw teeth 241 is 120-121 degrees, a conical counter bore 242 is arranged in the center of the third part 24, two notches 243 are symmetrically arranged on two sides of the conical counter bore 242, the counter bore angle of the conical counter bore 242 is 2 degrees, and the depth of the conical counter bore 242 is 3.7mm.

Fig. 9 is a schematic diagram of a use of a spinal screw according to an embodiment of the present invention, and fig. 10 is a schematic diagram of a connecting rod for use with a spinal screw according to an embodiment of the present invention, where, as shown in fig. 9 and 10, a connecting rod 4 for use with a spinal screw is provided with two grooves 41, and when in use, the connecting rod 4 is placed into two U-shaped openings 11 of a screw cap 1, so that the two grooves 41 of the connecting rod 4 are respectively clamped on the stopping blocks 33 of two stopping modules 3, and the two stopping blocks 33 are respectively clamped into the two grooves 41 of the connecting rod 4 to fix the connecting rod 4, thereby preventing the connecting rod 4 from laterally moving in the U-shaped openings 11 of the screw cap 1.

The embodiment of the invention provides a spine screw, a connecting rod with U-shaped openings at two sides is used, a screw cap with internal threads is clamped with the outer part, a distance stopping module is arranged in the screw cap, the distance stopping module comprises a distance stopping block base, a spring and distance stopping blocks, the distance stopping blocks are protruded out of the U-shaped opening gaps and are attached to grooves of the connecting rod, the connecting rod is prevented from moving after being implanted into a patient, a variable-pitch abnormal-shaped thread is arranged outside a screw rod, the screw rod is divided into three parts, a plurality of inverted teeth are arranged on the variable-pitch abnormal-shaped thread of a first part and used for increasing the stability of the screw, a plurality of waist-shaped through grooves with radial through holes are arranged on the variable-pitch abnormal-shaped thread of a second part and are communicated with the central holes of the screw rod and used for injecting bone cement, the third part is in a round table structure, gaps are arranged at two sides, 12 irregularly-shaped saw teeth are distributed on the head, the spine screw can be fully contacted with bone, the spine screw is reasonable in structure, the assembly is convenient, the performance is reliable, the hidden bone cement injection channel and the inverted teeth of the screw can be prevented from backing the screw, the related abnormal deformation and the occurrence of the back and the pain can be prevented from happening more clinically.

In the present invention, the term "plurality" means two or more, unless explicitly defined otherwise. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present invention, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "rear", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or units referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention.

In the description herein, the terms "one particular embodiment," "some embodiments," "one embodiment," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the scope of the invention, but to limit the invention to the particular embodiments, and any modifications, equivalents, improvements, etc. that fall within the spirit and principles of the invention are intended to be included within the scope of the invention.

Claims

1. A spinal screw, the spinal screw comprising:

2. The spinal screw of claim 1, wherein the crest width of the first gage thread is 0.25mm and the difference in height between the crests of the first gage thread and the crests of the second gage thread is 0.34mm.

3. The spinal screw of claim 1, wherein the adjacent face of the second pitch-varying thread to the first pitch-varying thread is a first flank, and wherein the angle of the first flank to the crest of the first pitch-varying thread is 88 °.

4. The spinal screw of claim 1, wherein the number of the barbs on the first torque conversion thread on the exterior of the first portion is 99 and the spacing between each two barbs is 1mm.

5. A spinal screw as recited in claim 1, wherein the minimum pitch of the pitch-varying profiled thread is 1.5mm and the maximum pitch of the pitch-varying profiled thread is 3.5mm.

6. A spinal screw as recited in claim 1, wherein the angle of the radial included angle between two adjacent ones of said concave taper grooves in the same radial plane is 10 °;

7. A spinal screw as recited in claim 1, wherein the number of serrations of the head end of the third portion is 12, and wherein the serration has a tooth angle in the range of 120 ° to 121 °.

8. The spinal screw of claim 1, wherein the tapered counterbore of the third section is at an angle of 2 ° and a depth of 3.7mm.

9. A spinal screw as recited in claim 1, wherein the height of the spring is 3mm, the diameter of the wire of the spring is 0.2mm, the pitch of the spring is 0.5mm, the curvature coefficient of the spring is 4, the aspect ratio of the spring is 3.8, the helix angle of the spring is 12.1 °, and the spring modulus is 1.4.