CN215306576U

CN215306576U - Fastening piece

Info

Publication number: CN215306576U
Application number: CN202120372573.2U
Authority: CN
Inventors: 姚得志; 刘斌; 刘爽; 李健
Original assignee: Beijing Libeier Bio Engineering Institute Co Ltd
Current assignee: Beijing Libeier Bio Engineering Institute Co Ltd
Priority date: 2021-02-10
Filing date: 2021-02-10
Publication date: 2021-12-28
Anticipated expiration: 2031-02-10

Abstract

The present invention provides a fastener comprising: the rod body comprises a first rod section, a second rod section and an operation section which are sequentially connected; a first threaded section disposed on the first rod section; a second threaded section disposed on the second rod section, wherein a thread pitch of the first threaded section is greater than a thread pitch of the second threaded section. The technical scheme of this application has solved the pedicle of vertebral arch screw of single thread screw among the correlation technique effectively and has relatively poor to the fixed effect of outside hard cortex bone, perhaps the pedicle of vertebral arch screw of double thread screw is to the relatively poor problem of fixed effect of inside cancellous bone.

Description

Fastening piece

Technical Field

The utility model relates to the field of medical instruments, in particular to a fastener.

Background

The pedicle is a portion of the vertebral arch that originates in the posterior superior portion of the vertebral body, and is short and thick. The vertebral pedicle is vertically arranged with the vertebral body and protrudes to the back. As shown in figure 1, the pedicle 1 is curved in shape, and the pedicle 1 is fused with a vertebral body 2, an articular process 3 and a vertebral plate 4. The pedicle 1 is an integral part of the intervertebral foramen 5. The vertebral pedicle is also the strongest bony structure between the connecting vertebral body and the vertebral plate, and the screw fixation through the vertebral pedicle can provide reliable mechanical basis for reconstructing the stability of the vertebral column. Currently, the internal fixation of the spine is mainly fixed by implanting pedicle screws into the pedicles of the spine.

At present, the thread forms of the common pedicle screws are generally two, wherein one thread is a single thread and the other thread is a double thread. The outer part of the pedicle is cortical bone, the inner part is cancellous bone, and the cortical bone is harder, while the cancellous bone is softer. If the vertebral pedicle has osteoporosis, the spongy bone is softer.

In the related art, if the single-thread pedicle screw is used for a fixation operation of implanting into a pedicle, the single-thread pedicle screw can better grip the inner cancellous bone when being screwed in due to the larger thread pitch of the single-thread pedicle screw, but has a poor fixation effect with the outer hard cortical bone, and is easy to break. If the fixed operation in the pedicle of vertebral arch screw implantation pedicle of adoption double-thread screw, because the pitch of double-thread screw is less, when the screw in, it can be fixed mutually with outside cortex bone betterly, nevertheless can't grab inside cancellous bone well, leads to the pedicle of vertebral arch screw to become flexible easily, and stability is relatively poor.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide a fastener to solve the problems that in the related art, a single-thread pedicle screw has poor fixing effect on external hard cortical bone, or a double-thread pedicle screw has poor fixing effect on internal cancellous bone.

In order to achieve the above object, the present invention provides a fastener comprising: the rod body comprises a first rod section, a second rod section and an operation section which are sequentially connected; a first threaded section disposed on the first rod section; a second threaded section disposed on the second rod section, wherein a thread pitch of the first threaded section is greater than a thread pitch of the second threaded section.

Further, the major diameter dimension of the first thread segments is equal to the major diameter dimension of the second thread segments.

Further, the minor dimension of the first thread segments is equal to the minor dimension of the second thread segments.

Further, the first thread section is a first thread section, and the second thread section is a double-thread.

Further, the height of the thread ridges of the first thread segments and/or the second thread segments is in the range of 0.5mm to 1.15 mm.

Furthermore, one end of the first rod section, which is far away from the second rod section, is an implantation section, and the diameter of the implantation section is gradually reduced from the second rod section to the first rod section.

Further, the length of the first pole segment is smaller than the length of the second pole segment, wherein the length of the second pole segment is in the range of 20mm to 30 mm.

Further, the distance between the tips of two adjacent threads of the first thread segments is in the range of 3mm to 6 mm.

Further, the distance between the tips of two adjacent threads of the second thread segments is in the range of 1.5mm to 3 mm.

Further, the operation section is in a U shape.

By applying the technical scheme of the utility model, the fastener comprises: the bolt comprises a rod body, a first thread section and a second thread section. The body of rod is including the first pole section, second pole section and the operation section that connect gradually. The first thread segment is disposed on the first rod segment. The second threaded section is disposed on the second rod section, wherein the thread pitch of the first threaded section is greater than the thread pitch of the second threaded section. Therefore, in the fixing operation of implanting the fastener into the vertebral pedicle, the first thread section can better grip the inner cancellous bone when being screwed into the vertebral body due to the larger thread pitch of the first thread section so as to fix the inner cancellous bone. Because the screw pitch of the second thread section is smaller, when the second thread section is screwed into the pedicle of a vertebral arch, the second thread section can be better positioned in the pedicle of a vertebral arch so as to fix the external cortical bone with higher bone density. Like this, the fastener of this application can compromise the characteristics of two kinds of screw threads to make the whole of fastener can fix in the pedicle of vertebral arch better, synthesize the resistance to plucking out of improvement screw thread. And the design of the first thread section can improve the screwing-in torque of the fastener, and can still ensure that the fastener has effective holding force under the condition of osteoporosis of an elderly patient. The design of the second thread section can improve the screwing-in speed of the fastener, shorten the operation time and reduce the risk of postoperative infection of a patient. Therefore, the technical scheme of this application has solved effectively that single thread's pedicle of vertebral arch screw is relatively poor to the fixed effect of outside hard cortex bone among the correlation technique, or the pedicle of vertebral arch screw of double thread is relatively poor to the fixed effect of inside cancellous bone problem.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

FIG. 1 shows a perspective schematic view of a fastener implanted within a pedicle, according to an embodiment of the fastener of the present invention;

FIG. 2 shows a perspective view of the fastener of FIG. 1; and

fig. 3 shows a front view of the fastener of fig. 1.

Wherein the figures include the following reference numerals:

1. a pedicle of a vertebral arch; 2. a vertebral body; 3. articular process; 4. a vertebral plate; 5. an intervertebral foramen; 10. a rod body; 11. a first pole segment; 12. a second pole segment; 13. an operation section; 20. a first thread segment; 30. a second thread segment.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the utility model, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

As shown in fig. 1 and 2, the fastener of the present embodiment includes: a shank 10, a first threaded section 20 and a second threaded section 30. The rod body 10 includes a first rod section 11, a second rod section 12 and an operation section 13 connected in sequence. The first thread segment 20 is provided on the first rod segment 11. A second thread section 30 is provided on the second rod section 12, wherein the thread pitch of the first thread section 20 is greater than the thread pitch of the second thread section 30.

With the solution of the present embodiment, the pitch of the first thread segments 20 is greater than the pitch of the second thread segments 30. Thus, in the fixing operation of the fastener implanted into the pedicle of vertebral arch, the first thread section 20 can better grasp the inner cancellous bone to fix the inner cancellous bone when being screwed into the vertebral body due to the larger thread pitch of the first thread section 20. Due to the fact that the thread pitch of the second thread section is small, when the second thread section 30 is screwed into the pedicle of a vertebral arch, the second thread section 30 can be well located in the pedicle of the vertebral arch so as to fix external cortical bone with high bone density. Like this, the fastener of this embodiment can compromise the characteristics of two kinds of screw threads to make the whole of fastener can fix in the pedicle of vertebral arch better, synthesize the resistance to plucking out of improvement screw thread. And the design of the first thread segments 20 can improve the screwing-in torque of the fastener, and can still ensure that the fastener has effective holding force under the condition of osteoporosis of old patients. The design of the second thread segments 30 can increase the speed of screwing in the fastener, shorten the operation time, and reduce the risk of postoperative infection of the patient. Therefore, the technical scheme of this embodiment has solved effectively that single thread pedicle screw is relatively poor to the fixed effect of outside hard cortex bone among the relevant art, or the pedicle screw of double thread is relatively poor to the fixed effect of inside cancellous bone.

As shown in fig. 2 and 3, the major diameter dimension of the first thread segments 20 is equal to the major diameter dimension of the second thread segments 30 for ease of manufacturing and forming. The "major diameter of the first thread segments 20" referred to above means the outer diameter of the first thread segments 20. The "major diameter of the second thread segments 30" referred to above refers to the outer diameter of the second thread segments 30. The major diameters of the first thread segments 20 and the major diameters of the second thread segments 30 are indicated by D1.

As shown in fig. 2 and 3, the minor dimension of the first thread segments 20 is equal to the minor dimension of the second thread segments 30 for ease of manufacturing and forming. The "minor diameter of the first thread segments 20" referred to above means the inner diameter of the first thread segments 20. The "minor diameter of the second thread segments 30" referred to above means the inner diameter of the second thread segments 30. The minor diameter of the first thread segments 20 and the minor diameter of the second thread segments 30 are each designated D2.

As shown in fig. 2 and 3, for the convenience of processing and the reduction of processing cost, the first thread segments 20 are first thread segments, and the second thread segments 30 are double threads.

As shown in fig. 2 and 3, in order to provide the first thread segments 20 and the second thread segments 30 with the pull-out resistance, the heights H of the thread teeth of the first thread segments 20 and the second thread segments 30 are each in the range of 0.5mm to 1.15 mm. Preferably, the height H of the thread ridges of the first thread segments 20 and the second thread segments 30 is 0.8mm or 1 mm.

Of course, in embodiments not shown in the figures, the height H of the thread ridges of the first thread segments or the second thread segments may be in the range of 0.5mm to 1.15 mm.

As shown in fig. 2 and 3, the end of the first rod segment 11 away from the second rod segment is an implantation segment, and the diameter of the implantation segment gradually decreases from the second rod segment 12 to the first rod segment 11. Therefore, the implantation section has better guidance, and can be conveniently screwed without specially arranging a self-tapping groove. And the end of the implantation section is a rounded head, so that the design of the rounded head allows a doctor to adopt a double-skin fixed approach to the nail. The diameter of the implant section decreases gradually from the second section 12 to the first section 11 to form a taper V, preferably 9 °.

As shown in fig. 2 and 3, the length of the first pole segment 11 is smaller than the length of the second pole segment 12. Wherein the length L1 of the second pole segment 12 is in the range of 20mm to 30 mm. Therefore, the fastener can effectively take into account the characteristics of two threads, so that the whole fastener can be better fixed in the pedicle of vertebral arch, and the anti-withdrawal force of the threads is comprehensively improved. The length L1 of the second pole segment 12 is preferably 25 mm. Preferably, the sum L2 of the length of the first pole segment 11 and the length of the second pole segment 12 is 40 mm.

As shown in fig. 2 and 3, the distance P1 between the tips of two adjacent threads of the first thread segment 20 is in the range of 3mm to 6 mm. The "distance P1" is the pitch of the first thread segments 20, and the "distance P1" is preferably 4 mm. A thread pitch in the range of 3mm to 6mm enables the first thread segments 20 to increase the screwing torque of the fastener, and in the case of osteoporosis in elderly patients, still ensures an effective holding force of the fastener.

As shown in fig. 2 and 3, the distance P2 between the tips of two adjacent threads of the second thread segments 30 is in the range of 1.5mm to 3 mm. The "distance P2" is the pitch of the second thread segments 30, and the "distance P2" is preferably 2 mm. The thread pitch in the range of 1.5mm to 3mm can enable the second thread section 30 to improve the screwing speed of the fastener, shorten the operation time and reduce the risk of postoperative infection of a patient.

As shown in fig. 2 and 3, the operating section 13 is U-shaped for ease of operation of the fastener. The U-shaped operating section 13 facilitates engagement with an operating tool to facilitate implantation of the fastener. The operating tool may be a nailing screwdriver.

As shown in fig. 3, in this embodiment, the thread angles of the first thread segments 20 and the second thread segments 30 are both 30 °, wherein the thread angle of 30 ° is equal to the sum of the dimension R1 and the dimension R2, the dimension R1 is 5 °, and the dimension R2 is 25 °. The root angles R3 of one side of the threads of the first thread segments 20 and the second thread segments 30 are both 0.6 deg., and the root angles R4 of the other side of the threads of the first thread segments 20 and the second thread segments 30 are both 0.4 deg..

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fastener, characterized by comprising:

the rod body (10) comprises a first rod section (11), a second rod section (12) and an operation section (13) which are connected in sequence;

a first threaded section (20) provided on the first rod section (11);

a second thread section (30) provided on the second rod section (12), wherein the thread pitch of the first thread section (20) is larger than the thread pitch of the second thread section (30).

2. A fastener according to claim 1, characterized in that the major diameter dimension of the first thread segment (20) is equal to the major diameter dimension of the second thread segment (30).

3. A fastener according to claim 1, characterized in that the minor dimension of the first thread segment (20) is equal to the minor dimension of the second thread segment (30).

4. A fastener according to claim 1, wherein the first thread section (20) is a first thread section and the second thread section (30) is a double thread.

5. A fastener according to claim 1, characterized in that the height (H) of the thread ridges of the first thread section (20) and/or the second thread section (30) is in the range of 0.5mm to 1.15 mm.

6. A fastener according to claim 1, characterized in that the end of the first segment (11) remote from the second segment is an implanted segment, the diameter of which decreases from the second segment (12) to the first segment (11).

7. Fastener according to claim 1, characterized in that the length of the first segment (11) is smaller than the length of the second segment (12), wherein the length (L1) of the second segment (12) is in the range of 20mm to 30 mm.

8. A fastener according to claim 1, characterized in that the distance (P1) between the tips of two adjacent thread teeth of the first thread section (20) is in the range of 3mm to 6 mm.

9. A fastener according to claim 1, characterized in that the distance (P2) between the tips of two adjacent thread teeth of the second thread segment (30) is in the range of 1.5mm to 3 mm.

10. Fastener according to claim 1, characterized in that said operating section (13) is U-shaped.