CN210301310U

CN210301310U - Dynamic locking spinal fusion cage

Info

Publication number: CN210301310U
Application number: CN201920705841.0U
Authority: CN
Inventors: 曹佳振; 徐文利
Original assignee: Chuanghui Medical Equipment Jiangsu Co ltd
Current assignee: Chuanghui Medical Equipment Jiangsu Co ltd
Priority date: 2019-05-15
Filing date: 2019-05-15
Publication date: 2020-04-14
Anticipated expiration: 2029-05-15

Abstract

The utility model relates to the field of medical equipment, concretely relates to developments locking backbone fuses ware. A dynamic locking spinal fusion cage comprises a fusion cage main body, wherein a screw hole for mounting a screw is formed in the fusion cage main body, the screw comprises a screw cap and a screw rod, and when the screw is mounted in the screw hole, the outer diameter of the screw rod in the screw hole is smaller than the aperture of the screw hole in which the screw rod is located; and an elastic locking piece for locking the screw is further arranged at the inlet of the screw hole. By setting the outer diameter of the screw rod to be smaller than the aperture of the screw hole, the screw can move in the screw hole within a certain angle range, and the dynamic installation of the screw is realized; and an elastic locking piece is further arranged at the inlet of the screw hole, so that the screw can be tightly pressed in the screw hole, and the screw is prevented from being separated. The technical problem that the fusion cage in the prior art is fixedly locked and is not beneficial to vertebral rehabilitation is solved.

Description

Dynamic locking spinal fusion cage

Technical Field

The utility model relates to the field of medical equipment, concretely relates to developments locking backbone fuses ware.

Background

Degenerative spinal diseases and structural damage are important causes of pain in the neck, shoulders, waist and legs, and impaired or even lost sensory and motor functions. In the last 50 s, Cloward first proposed posterior lumbar fusion (PLIF), a technique developed as one of the basic surgical procedures for spinal surgery today. Badgy and Kuslich designed an interbody fusion Cage (Cage) suitable for use in humans in 1986, namely the BAK (Bagby and Kuslich) system. Since then, the interbody bone-grafting fusion technology has been greatly developed, and becomes a basic operation mode for treating spinal degenerative diseases and structural injuries. The design principle of the interbody fusion Cage (Cage) is based on the distraction-compression-stabilization (distraction stabilization) effect proposed by Bagby. The principle is that after the intervertebral fusion cage is implanted, the muscle, the fibrous ring and the anterior and posterior longitudinal ligaments of the fusion segment can be in a continuous tension state by the distraction force, so that the fusion segment and the fusion cage can be fixed in a three-dimensional super-static manner. Second, the interbody Cage (Cage) has good anatomical support function. On one hand, the stress and the stability of the front and middle columns of the spine are recovered by recovering the height of the intervertebral space, the inherent physiological bulge of the spine is recovered, maintained and stabilized, the intervertebral foramen is enlarged, and the compression of the dural sac and the nerve root is relieved. The recovery of intervertebral space height can indirectly refore because the losing of intervertebral space height and the fibrous ring that leads to folding ligamentum flavum and compressed to make the stenosis of central vertebral canal obtain improving obviously, increase the anterior-posterior footpath of vertebral canal, occupy-place in the original vertebral canal is alleviateed. On the other hand, fixation of Cage assisted by pedicle screws or steel plate screws can also provide immediate and early fusion stability for the spine. The shear and rotation resisting effect can be obtained by expanding the acting force and the reacting force generated by compression. The hollow structure of the Cage provides a good mechanical environment for the fusion of the cancellous bone therein, thereby achieving the purpose of interface permanent fusion.

Since the intervertebral fusion technology is clinically applied, the intervertebral fusion devices clinically used can be classified into ① metal fusion devices, most of which are titanium alloy fusion devices, such as TFC, Harms, BAK intervertebral fusion devices, and the like, ② nonmetal fusion devices, such as Brantigan carbon fiber fusion device, high polymer polyether ether ketone (PEEK), absorbable poly D, L-lactide (PDLLA) fusion device, and the like, the metal intervertebral fusion devices currently used for manufacturing the intervertebral fusion devices are mainly made of titanium alloy, represented by BAK and Ray TFC, and the indications of the metal intervertebral fusion devices are enlarged to lumbar isthmus parts, such as collapse and instability, lumbar vertebra, and the like, and the nonmetal intervertebral fusion devices currently used clinically are non-absorbable type intervertebral fusion devices, and are mainly made of carbon fiber (carbon fiber) and polyether ether ketone (PEEK) materials.

For example, the application with the application number of 201520735767.9 discloses a cervical vertebra single item intervertebral fusion fixing device, and specifically discloses: the device comprises a screw fixing part at the front end and an intervertebral fusion part at the rear end; the left side and the right side of the screw fixing part are respectively provided with symmetrically distributed screw holes which are inclined so that the screws can fix the intervertebral fusion part on an end plate of a lower segment vertebral body of the dislocation facet joint through the screw holes; a locking device is arranged between the screw holes and is used for locking the screw inserted into the screw hole so as to prevent the screw from falling out, so that the intervertebral fusion part is suitable to be placed between two vertebral bodies after the dislocation and reduction of the facet joints at both sides of the cervical vertebra and is used for replacing the intervertebral disc removed in the cervical vertebra operation. In the fusion fixing device in the above application, the screw is fixed and locked, and dynamic locking cannot be realized, so that the vertebral body rehabilitation is not facilitated.

SUMMERY OF THE UTILITY MODEL

The fusion cage that exists is fixed locking in order to solve among the prior art, is unfavorable for the recovered technical problem of centrum, the utility model provides a developments locking backbone fusion cage has solved above-mentioned technical problem. The technical scheme of the utility model as follows:

a dynamic locking spinal fusion cage comprises a fusion cage main body, wherein a screw hole for mounting a screw is formed in the fusion cage main body, the screw comprises a screw cap and a screw rod, and when the screw is mounted in the screw hole, the outer diameter of the screw rod in the screw hole is smaller than the aperture of the screw hole in which the screw rod is located; and an elastic locking piece for locking the screw is further arranged at the inlet of the screw hole.

Furthermore, the side surface of the screw cap is a spherical surface, and the screw rod in the screw hole is in a smooth rod shape.

Furthermore, the screw hole comprises a front section hole and a rear section hole which are communicated, the screw cap is accommodated in the front section hole, the screw rod is accommodated and partially extends out of the rear section hole, and the screw rod extending out of the rear section hole is provided with locking threads.

Further, the axes of the screw holes are disposed obliquely with respect to the vertebra engaging surface of the cage body.

Further, the number of the screw holes is at least two, the axis of at least one screw hole is obliquely arranged upwards, and the axis of at least one screw hole is obliquely arranged downwards.

Further, the elastic locking piece is an elastic ring, and the elastic ring presses on the screw cap of the screw.

Further, the number of the screw holes is at least two, and the elastic locking piece is positioned between inlets of two adjacent screw holes and compresses the screws in the two adjacent screw holes.

Further, a groove is formed between every two adjacent screw holes, the elastic locking piece is arranged in the groove through a clamping ring, and the elastic locking piece extends into the two adjacent screw holes respectively.

Further, the vertebra joint surface of the fusion cage body is provided with an anti-slip structure, and the fusion cage body is provided with a bone grafting window.

Furthermore, a developing piece is embedded on the fusion device main body.

Based on the technical scheme, the utility model discloses the technological effect that can realize does:

1. the utility model discloses a dynamic locking spinal fusion cage, through setting the external diameter of the screw rod to be smaller than the aperture of the screw hole, the screw can move in the screw hole within a certain angle range, thus realizing the dynamic installation of the screw; an elastic locking piece is further arranged at an inlet of the screw hole, the screw can be tightly pressed in the screw hole, and the screw is prevented from falling off;

2. the dynamic locking spinal fusion cage of the utility model is provided with the spherical nail cap, so that the dynamic locking spinal fusion cage can rotate in the screw hole to realize dynamic locking; the screw rod in the screw hole is arranged to be in a smooth rod shape, so that the screw can move in the screw hole conveniently, the processing difficulty is reduced, and the dynamic installation of the screw is facilitated; the screw rod extending out of the screw hole is provided with locking threads, so that the screw and the vertebral body can be conveniently and fixedly connected;

3. the utility model discloses a dynamic locking spinal fusion cage, the screw hole is obliquely arranged relative to the vertebra joint surface of the fusion cage main body, so that the part of the screw extends out of the vertebra joint surface and is connected with the vertebral body after being installed on the screw hole; at least two screw holes are further arranged, at least one screw hole is inclined upwards, and at least one screw hole is inclined downwards, so that at least one screw can be obliquely upwards fixedly connected with the vertebral body above the fusion cage body, and at least one screw can be obliquely downwards fixedly connected with the vertebral body below the fusion cage body, and the fusion cage body is fixedly connected with the upper vertebral body and the lower vertebral body;

4. the utility model discloses a dynamic locking spinal fusion cage, which is provided with an elastic locking piece, wherein the elastic locking piece is an elastic ring arranged between two screw holes through a clamping ring, and the elastic locking piece respectively extends into the openings of two adjacent screw holes so as to compress screws and prevent the screws from being separated from the screw holes; an elastic locking piece compresses tightly two screws simultaneously, reduces the quantity of spare part, the cost is reduced. Alpha

Drawings

FIG. 1 is a schematic structural view of the dynamic locking spinal fusion cage of the present invention;

FIG. 2 is an exploded view of a dynamic locking spinal fusion cage;

FIG. 3 is a schematic structural view of the fusion cage body;

FIG. 4 is a state view of the screw in the cage body;

FIG. 5 is an enlarged view of portion A of FIG. 4;

FIG. 6 is a view of the screw prior to insertion into the screw hole;

FIG. 7 is a view of the screw after it has been inserted into the screw hole;

in the figure: 1-a cage body; 11-a vertebral engaging surface; 111-anti-skid structure; 12-bone grafting window; 13-screw holes; 131-a front section hole; 132-posterior segment orifice; 14-a developing member; 15-a groove; 2-a screw; 21-nail cap; 22-nail rod; 3-a resilient locking member; 4-buckling.

Detailed Description

The invention will be further described with reference to the accompanying drawings. In the description of the present invention, it is to be understood that the terms "radial", "axial", "upper", "lower", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience in describing the present invention and for simplification of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

As shown in fig. 1 to 7, the present embodiment provides a dynamic locking spinal fusion cage, which comprises a cage body 1 and a screw 2, wherein the cage body 1 is provided with a screw hole 13, and the screw 2 is mounted in the screw hole 13 to lock the cage body 1 in a vertebral body of a human body.

The cage body 1 is approximately rectangular in shape, the cage body 1 having upper and lower vertebral engaging surfaces 11, the upper vertebral engaging surface 11 interfacing with an upper vertebral body and the lower vertebral engaging surface 11 interfacing with a lower vertebral body. Preferably, the two vertebra engaging surfaces 11 are both provided with anti-slip structures 17, preferably, the anti-slip structures 17 are anti-slip teeth, the two vertebra engaging surfaces 11 of the fusion cage body 1 are distributed with anti-slip teeth, the contact area between the fusion cage and the vertebral body is increased by arranging the anti-slip teeth, the friction force between the fusion cage and the vertebral body is increased, the fusion cage is fixed and stable, the fusion cage is prevented from slipping out of the vertebral body, and the purpose of fusion is achieved. Be provided with in the integration ware main part 1 and plant bone window 12 for hold autologous bone, xenogeneic bone or artificial bone, the number of planting bone window 12 in this embodiment is two.

The fusion cage main body 1 is also provided with a developing part 14, and the developing part 14 is used for developing in the operation, so that the position of the fusion cage is convenient to determine. Specifically, the fusion cage body 1 is provided with a mounting hole in which the developing member 14 is accommodated. Preferably, the fuser body 1 is opened with a plurality of mounting holes, and the number of the developing members 14 corresponds to the number of the mounting holes. Further preferably, mounting holes are provided in the middle of the fuser body 1 and the inner end of the fuser body 1, and the developing member 14 is a developing rod which can be easily inserted into the mounting holes. The number of the developing devices 14 is set to 3 in this embodiment.

The fusion cage body 1 is also provided with a screw hole 13, the screw hole 13 is arranged at the outer end of the fusion cage body 1, the screw hole 13 is oriented to implant the screw 2, and the screw hole 13 partially penetrates through the fusion cage body 1. Specifically, a screw hole 13 extends from the outer end face of the cage body 1 to communicate with the bone grafting window 12, and the axis of the screw hole 13 is disposed obliquely with respect to the vertebra engaging surface 11 of the cage body 1. Preferably, there are at least two screw holes 13, at least one of the screw holes 13 having an axis disposed obliquely upward relative to the axis of the superior vertebra engaging surface 11, such that the screw 2 received in said screw hole 13 extends at least partially out of the superior vertebra engaging surface 11 into the superior vertebral body; the axis of at least one screw hole 13 is disposed obliquely downward relative to the axis of the lower vertebrae engaging surface 11 so that a screw 2 mounted in said screw hole 13 can extend at least partially out of the lower vertebrae engaging surface 11 into the lower vertebrae.

The screw 2 is accommodated and extends out of the screw hole 13, specifically, the screw 2 comprises a screw cap 21 and a screw rod 22, the screw hole 13 comprises a front section hole 131 and a rear section hole 132 which are communicated, and the rear section hole 132 is communicated with the bone grafting window 12. The nut 21 is received in the forward section aperture 131 and the shank 22 is received and partially extends out of the rearward section aperture 132. More specifically, the side surface of the nut 21 is spherical, and the inner wall of the front section hole 131 is correspondingly spherical, so that the nut 21 can rotate relative to the front section hole 131; the portion of the shank 22 within the rear section bore 132 is a smooth rod and the portion of the shank 22 extending out of the rear section bore 132 is provided with locking threads. Preferably, the outer diameter D of the smooth rod-shaped portion of the nail body 22 located in the rear-stage hole 132 is smaller than the bore diameter D of the rear-stage hole 132, so that the screw 2 can deflect within the screw hole 13 by the angle a, thereby achieving dynamic locking.

To achieve locking of the screw 2 in the screw hole 13, a resilient locking member 3 for locking the screw 2 is also provided on the outer end of the cage body 1. Specifically, the inlets of two adjacent screw holes 13 are provided with a groove 15, the groove 15 is communicated with the two adjacent screw holes 13 in the radial direction, the elastic locking piece 3 is arranged in the groove 15, at least part of the elastic locking piece 3 can extend into the two adjacent screw holes 13 respectively and is positioned on the outer side of the screw cap 21 of the screw 2, and the screw 2 is prevented from being pulled out of the screw holes 13. Specifically, the elastic locking member 3 is an elastic ring, and the elastic ring is pressed in the groove 15 by the snap ring 4. Further specifically, the elastic ring is annular, the snap ring 4 penetrates through the elastic ring, the outer end of the snap ring 4 is provided with a protruding outer edge, the protruding outer edge of the snap ring 4 compresses the elastic ring in the groove 15, and the other end of the snap ring 4 penetrates through the fusion cage body 1 to be reversely riveted in the bone grafting window 12, so that the elastic ring cannot fall off. The protruding outer edge of the snap ring 4 does not extend into the screw hole 13 and does not obstruct the mounting of the screw 2. The elastic locking piece 3 is made of an elastic material, so that the elastic locking piece 3 can be extruded in the implantation process of the screw 2 and enters the front section hole 131; when the screw 2 swings after being implanted, the elastic locking piece 3 can deform to adapt to the swing of the screw 2.

Preferably, the snap ring 4 is hollow, and a snap ring hole is formed in the middle of the snap ring, and the developing member 14 can be installed in the snap ring hole.

As shown in fig. 6-7, after the fusion cage body 1 is implanted into a vertebral body, the screw 2 is screwed into the screw hole 13, the spherical side surface of the screw cap 21 presses the elastic locking member 3 to deform the elastic locking member 3 until the screw cap 21 is pressed into the elastic locking member 3 and then contacts with the wall of the front section hole 131 of the screw hole 13, at this time, the elastic locking member 3 returns to a free state, and the elastic locking member 3 locks the screw 2 in the screw hole 13 so that the screw cannot be removed. The screw hole 13 is in a spherical structure and is in contact with the nut 21 of the screw 2, the aperture D of the rear section hole 131 of the screw hole 13 is larger than the outer diameter D of the smooth rod-shaped part of the screw 2, and the design can ensure that the screw 2 can swing within a certain range after being implanted.

The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.

Claims

1. A dynamic locking spinal fusion cage comprises a fusion cage main body (1), wherein a screw hole (13) for installing a screw (2) is formed in the fusion cage main body (1), and the dynamic locking spinal fusion cage is characterized in that the screw (2) comprises a screw cap (21) and a screw rod (22), and when the screw (2) is installed in the screw hole (13), the outer diameter of the screw rod (22) positioned in the screw hole (13) is smaller than the aperture of the screw hole (13) where the screw rod is positioned; and an elastic locking piece (3) for locking the screw (2) is arranged at the inlet of the screw hole (13).

2. A dynamic locking spinal fusion cage as claimed in claim 1 wherein the side surface of the nut (21) is spherical and the stem (22) within the screw hole (13) is smooth rod-like.

3. A dynamic locking spinal fusion cage as claimed in claim 2 wherein the screw hole (13) includes a leading section hole (131) and a trailing section hole (132) in communication, the nut (21) is received in the leading section hole (131), the stem (22) is received in and partially extends out of the trailing section hole (132), and locking threads are provided on the stem (22) extending out of the trailing section hole (132).

4. A dynamic locking spinal fusion cage according to claim 1 in which the axes of the screw holes (13) are obliquely disposed relative to the vertebral engaging surface (11) of the cage body (1).

5. A dynamic locking spinal fusion cage according to claim 4 wherein there are at least two screw holes (13), at least one screw hole (13) having its axis obliquely upwardly disposed and at least one screw hole (13) having its axis obliquely downwardly disposed.

6. A dynamic locking spinal fusion cage according to claim 1 characterized in that the elastic locking element (3) is an elastic ring which presses on the nut (21) of the screw (2).

7. A dynamic locking spinal fusion cage according to claim 6 in which there are at least two screw holes (13) and the flexible locking element (3) is located between the entrances of two adjacent screw holes (13) to compress the screws (2) in two adjacent screw holes (13).

8. A dynamic locking spinal fusion cage according to claim 7 wherein a recess (15) is provided between two adjacent screw holes (13), the flexible locking element (3) being disposed within the recess (15) by a snap ring (4), the flexible locking element (3) extending into each of the two adjacent screw holes (13).

9. A dynamically locking spinal fusion cage according to claim 1 in which the cage body (1) is provided with a non-slip feature (111) on the vertebra engaging surface (11) and a bone graft window (12) on the cage body (1).

10. A dynamic locking spinal fusion cage according to claim 1 in which a visualization member (14) is embedded on the cage body (1).