Distraction fusion cage capable of being independently adjusted in multiple directions

Abstract

The utility model discloses a multidirectional independently adjustable strutting fusion cage, which comprises a main body, an upper supporting plate, a lower supporting plate, a left supporting plate, a right supporting plate, a first gear shaft and a second gear shaft, the upper supporting plate, the lower supporting plate, the left supporting plate and the right supporting plate are respectively positioned on the upper surface, the lower surface, the left surface and the right surface of the main body, and the first gear shaft and the second gear shaft are arranged inside the main body. The upper supporting plate, the lower supporting plate, the left supporting plate and the right supporting plate are respectively connected with the gear shaft through racks; the upper supporting plate, the lower supporting plate, the left supporting plate and the right supporting plate can be opened independently, adjustment in the horizontal direction and the vertical direction is achieved, opening of the upper supporting plate and the lower supporting plate can play a role in adjusting and supporting the upper lumbar vertebra and the lower lumbar vertebra, opening of the left supporting plate and the right supporting plate can play a role in squeezing crushed bones placed in a target intervertebral space in advance, and then the crushed bones are pressurized. The effect of supporting the upper and lower lumbar vertebrae is achieved to a certain extent, and intervertebral fusion is facilitated.

Description

Technical Field

[0001] The utility model relates to a fusion device, in particular to a multi-directionally independently adjustable expandable fusion device. Background Art

[0002] Lumbar interbody fusion cages were first used after spinal fusion in 1988. They have become one of the basic procedures for treating lumbar degenerative diseases and spondylolisthesis because of their advantages in reconstructing the immediate stability of the spine and improving the bone graft fusion rate. Various interbody fusion techniques with different approaches are widely used in the surgical treatment of lumbar diseases. With the development of minimally invasive spinal surgery and material technology, the advent of expandable fusion cages has overcome the defects of traditional static fusion cages. They have the characteristics of small implant size and large expansion size, which not only meets the biomechanical function, but also caters to the needs of minimally invasive surgery.

[0003] Currently, various expandable fusion devices have been developed and applied. Their main principles and functions are similar, but they all have the following problems: First, the currently available expandable fusion devices can only be expanded in a single horizontal direction or vertical direction, and cannot take both into account; second, the currently available expandable fusion devices cannot adjust the expansion range in multiple directions according to the actual situation of the patient to increase the contact area of ​​the fusion device and restore the physiological lordosis of the lumbar spine; finally, after the expandable fusion device is expanded, although the height is restored, it cannot pressurize the surrounding bone fragments that have been placed, so it is not conducive to fusion. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the utility model provides a multi-directional independently adjustable expandable fusion device, which can be expanded independently in the horizontal direction and the vertical direction. In addition to providing support, it can also pressurize the broken bones, which is beneficial to improve the fusion effect.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a multi-directional independently adjustable expandable fusion device, comprising a main body, and also comprising an upper support plate, a lower support plate, a left support plate, a right support plate, a first gear shaft and a second gear shaft; the main body is hollow inside, and the front and rear sides of the main body are respectively provided with a first sleeve and a second sleeve, and the first sleeve and the second sleeve are connected to the front and rear sides of the main body. Holes with the same cross-sectional shape as the sleeves are provided, and the first sleeve and the second sleeve are coaxial; a first gear is provided at the rear of the first gear shaft, a first plug hole is provided in the first gear shaft, and a first spline groove is provided in the middle of the first plug hole; a second gear is provided at the front of the second gear shaft, a second plug hole is provided in the second gear shaft, and a second spline groove is provided in the middle of the second plug hole; the front of the first gear shaft is inserted in the first sleeve, and the rear of the second gear shaft is inserted in the second sleeve, and the length of the first gear shaft and the second gear shaft The sum is equal to the length between the front side and the rear side of the main body; a limit slot is respectively provided inside the upper and lower side surfaces of the main body, and the extension lines of the upper and lower limit slots are tangent to the first gear and the upper and lower limit slots are rotationally symmetrical structures; a limit slot is also respectively provided inside the left and right side surfaces of the main body, and the extension lines of the left and right limit slots are tangent to the second gear and the left and right limit slots are rotationally symmetrical structures; racks are provided on the inner sides of the upper support plate, the lower support plate, the left support plate and the right support plate, and the upper support plate, the lower support plate, the left support plate and the right support plate are respectively located on the outside of the upper side surface, the lower side surface, the left side surface and the right side surface of the main body, and the racks on the inner sides of the upper support plate and the lower support plate respectively pass through the limit slots inside the upper side surface and the lower side surface of the main body and then mesh with the first gear, and the racks on the inner sides of the left support plate and the right support plate respectively pass through the limit slots inside the left side surface and the right side surface of the main body and then mesh with the second gear.

[0006] Furthermore, the corners of the main body are configured to be in an arc shape.

[0007] Furthermore, the shapes of the upper support plate, the lower support plate, the left support plate and the right support plate are completely the same as the upper, lower, left and right sides of the main body.

[0008] Furthermore, the inner wall surfaces of the first sleeve and the second sleeve are frosted surfaces.

[0009] Furthermore, the surfaces of the front portion of the first gear shaft and the rear portion of the second gear shaft are both frosted surfaces.

[0010] Compared with the prior art, the upper and lower support plates and the left and right support plates of the utility model can be expanded separately to achieve adjustment in both horizontal and vertical directions. The expansion of the upper and lower support plates can play a role in adjusting and supporting the upper and lower lumbar vertebrae, and the expansion of the left and right support plates can squeeze the previously inserted bone fragments in the target intervertebral space, that is, to achieve the effect of pressurizing the bone fragments, and also play a role in supporting the upper and lower lumbar vertebrae to a certain extent, which is beneficial to intervertebral fusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0012] Figure 2 This is a schematic diagram of the internal structure of the main body of the utility model;

[0013] Figure 3 This is a schematic diagram of the structure of the first gear shaft of the utility model;

[0014] Figure 4 This is a schematic diagram of the structure of the second gear shaft of the utility model;

[0015] Figure 5 This is a schematic diagram of the meshing structure of the upper support plate, the lower support plate and the first gear of the utility model;

[0016] Figure 6 This is a schematic diagram of the initial state structure of the utility model;

[0017] Figure 7 This is a front view of the utility model in the expanded state;

[0018] Figure 8 This is a schematic diagram of the initial state structure of the utility model in the target intervertebral space;

[0019] Fig. 9 This is a schematic diagram of the structure of the utility model in the expanded state in the target intervertebral space;

[0020] In the figure: 1. main body; 11. first sleeve; 12. second sleeve; 2. upper support plate; 3. lower support plate; 4. left support plate; 5. right support plate; 6. first gear shaft; 61. first gear; 62. first plug hole; 63. first spline groove; 7. second gear shaft; 71. second plug hole; 73. second spline groove; 8. rack; 9. limit slot. DETAILED DESCRIPTION

[0021] The utility model will be further described below in conjunction with the accompanying drawings.

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] like Figures 1 to 4 As shown, the utility model provides a technical solution: including a main body 1, an upper support plate 2, a lower support plate 3, a left support plate 4, a right support plate 5, a first gear shaft 6 and a second gear shaft 7.

[0024] like Figure 2As shown, the main body 1 is hollow inside, and the first sleeve 11 and the second sleeve 12 are respectively provided inside the front and rear sides of the main body 1. Holes with the same shape as the cross-section of the sleeves are opened at the connection between the first sleeve 11, the second sleeve 12 and the front and rear sides of the main body 1, and the first sleeve 11 is coaxial with the second sleeve 12; the first sleeve 11 and the second sleeve 12 are used to support the first gear shaft 6 and the second gear shaft 7.

[0025] like Figure 3 As shown, a first gear 61 is provided at the rear of the first gear shaft 6, a first insertion hole 62 is provided in the first gear shaft 6, and a first spline groove 63 is provided in the middle of the first insertion hole 62; Figure 4 As shown, the front part of the second gear shaft 7 is provided with a second gear 71, a second insertion hole 72 is provided in the second gear shaft 7, a second spline groove 73 is provided in the middle of the second insertion hole 72, and the first spline groove 63 and the second spline groove 73 have the same groove shape; Figure 5 As shown, the front part of the first gear shaft 6 is inserted into the first sleeve 11, and similarly, the rear part of the second gear shaft 7 is inserted into the second sleeve 12, and the sum of the lengths of the first gear shaft 6 and the second gear shaft 7 is equal to the length between the front side and the rear side of the main body 1; after the first gear shaft 6 and the second gear shaft 7 are set, the first insertion hole 62 and the second insertion hole 72 are also coaxial, and the insertion holes are for the adjusting rod to pass through, and the front end of the adjusting rod is provided with a spline, and the spline shape is the same as the groove shape of the first spline groove 63 and the second spline groove 73. When the spline of the front end of the adjusting rod is inserted into the first spline groove 63, the first gear shaft 6 and the first gear 61 can be driven to rotate by rotating the adjusting rod. Similarly, when the spline of the front end of the adjusting rod is inserted into the second spline groove 73, the second gear shaft 7 and the second gear 71 can be driven to rotate by rotating the adjusting rod.

[0026] like Figure 2 As shown, a limit slot 9 is respectively provided inside the upper and lower sides of the main body 1, and the extension lines of the upper and lower limit slots 9 are tangent to the first gear 61, and the upper and lower limit slots 9 are rotationally symmetrical structures; a limit slot 9 is also respectively provided inside the left and right sides of the main body 1, and the extension lines of the left and right limit slots 9 are tangent to the second gear 71, and the left and right limit slots 9 are rotationally symmetrical structures. The inner sides of the upper support plate 2, the lower support plate 3, the left support plate 4 and the right support plate 5 are all provided with a rack 8, and the upper support plate 2, the lower support plate 3, the left support plate 4 and the right support plate 5 are respectively located on the outer sides of the upper side, the lower side, the left side and the right side of the main body 1, as shown Figure 5As shown, the rack 8 on the inner side of the upper support plate 2 and the lower support plate 3 respectively passes through the limiting slots 9 inside the upper side and lower side of the main body 1 and then meshes with the first gear 61. Similarly, the rack 8 on the inner side of the left support plate 4 and the right support plate 5 respectively passes through the limiting slots 9 inside the left side and right side of the main body 1 and then meshes with the second gear 71; the rotation of the first gear 61 will drive the rack 8 to move up and down, that is, drive the upper support plate 2 and the lower support plate 3 to move up and down. Similarly, the rotation of the second gear 71 will drive the rack 8 to move left and right, that is, drive the left support plate 4 and the right support plate 5 to move left and right. Figure 7 The figure shows the fully expanded state of the utility model. Since the left support plate 4 and the right support plate 5 will also contact the upper and lower lumbar vertebrae, the left support plate 4 and the right support plate 5 are set to a certain thickness, which increases the contact area between the upper and lower sides of the left support plate 4 and the right support plate 5 and the lumbar vertebrae, reduces the chance of stress end plate collapse, and also improves the fusion effect to a certain extent.

[0027] like Figure 6 As shown, in a normal state, the utility model is in a contracted state, and the upper support plate 2, the lower support plate 3, the left support plate 4, and the right support plate 5 are all completely in contact with the side of the main body 1, and the volume is the smallest at this time; when in use, the utility model in the contracted state is implanted into the target intervertebral space of the patient. In this embodiment, the intervertebral space between L4 and L5 is the target intervertebral space, and the volume is the smallest in the contracted state, so it can be implanted into the target intervertebral space with the smallest possible wound surface. After implantation, the state is as shown Figure 8As shown; taking the first plug hole 62 facing the surgeon as an example, after the implant is in place, the adjusting rod is inserted into the first spline groove 63 in the first plug hole 62, and the first gear 61 is rotated to drive the first gear 61 to rotate. The rotation of the first gear 61 drives the upper support plate 2 to move upward while driving the lower support plate 3 to move downward, thereby realizing a separately adjustable support in the longitudinal direction; after the support in the longitudinal direction is adjusted, the adjusting rod continues to be inserted deeper, that is, the adjusting rod passes through the first plug hole 62 and then continues to be inserted into the second spline groove 73 in the second plug hole 72. When the adjusting rod is inserted into the second spline groove 73, the adjusting rod is rotated to drive the second gear 71 to rotate. The rotation of the second gear 71 drives the left support plate 4 to move to the left while driving the right support plate 5 to move to the right, thereby realizing a separately adjustable support in the transverse direction. The left support plate 4 and the right support plate 5 are The movement in the outward direction can squeeze the pre-inserted bone fragments on the left and right sides of the main body 1 in the target intervertebral space, that is, realize the bone fragment pressurization. The bone fragment pressurization can promote the fusion of the intervertebral space and improve the fusion effect. Since the axial center positions of the first spline groove 63 and the second spline groove 73 are both through, the adjustment rod can pass through. Therefore, in order to improve the pressurization effect on the bone fragments, the adjustment rod can pass through the first spline groove 63 and the second spline groove 73 in succession, and then implant the bone fragments from the inside of the adjustment rod into the target intervertebral space. At this time, the newly implanted bone fragments will fully squeeze the pre-implanted bone fragments on the front side of the main body 1, so as to achieve the purpose of pressurizing the bone fragments in the front direction of the main body 1 and further improve the fusion effect. After the adjustment is completed, the adjustment rod can be withdrawn from the second insertion hole 72 and the first insertion hole 62 in turn. The use state of the four support plates after being expanded is as shown in FIG. Fig. 9 Based on the bone data of the Chinese people, the expandable range in the width direction is 45-50 mm, that is, the distance between the left support plate 4 and the right support plate 5; the upper support plate 2 and the lower support plate 3 are made of porous titanium alloy material, which is conducive to bone growth and can further accelerate intervertebral fusion.

[0028] In order to reduce unnecessary damage to the patient during surgery, the utility model is preferably designed with a relatively smooth shape structure, such as setting the corners of the main body 1 to an arc shape; the shapes of the upper support plate 2, the lower support plate 3, the left support plate 4, and the right support plate 5 are exactly the same as the upper, lower, left, and right sides of the main body 1, and the volume can be reduced as much as possible when retracted. The inner wall surfaces of the first sleeve 11 and the second sleeve 12 are frosted surfaces, and the surfaces of the front of the first gear shaft 6 and the rear of the second gear shaft 7 are frosted surfaces. The surfaces of the gear shafts in contact with the sleeves are frosted surfaces, which greatly increases the resistance and can effectively maintain the state when expanded.

[0029] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0030] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any minor modifications, equivalent substitutions and improvements made to the above embodiments based on the technical essence of the present invention should be included in the protection scope of the technical solution of the present invention.

Claims

1. A multi-directional independently adjustable expandable fusion device, comprising a main body (1), characterized in that: It also includes an upper support plate (2), a lower support plate (3), a left support plate (4), a right support plate (5), a first gear shaft (6) and a second gear shaft (7); The main body (1) is hollow inside, and a first sleeve (11) and a second sleeve (12) are respectively provided inside the front and rear sides of the main body (1). A hole having the same shape as the sleeve cross section is provided at the connection between the first sleeve (11) and the second sleeve (12) and the front and rear sides of the main body (1), and the first sleeve (11) and the second sleeve (12) are coaxial. A first gear (61) is provided at the rear of the first gear shaft (6), a first insertion hole (62) is provided in the first gear shaft (6), and a first spline groove (63) is provided in the middle of the first insertion hole (62); a second gear (71) is provided at the front of the second gear shaft (7), a second insertion hole (72) is provided in the second gear shaft (7), and a second spline groove (73) is provided in the middle of the second insertion hole (72); The front part of the first gear shaft (6) is inserted into the first sleeve (11), and the rear part of the second gear shaft (7) is inserted into the second sleeve (12), and the sum of the lengths of the first gear shaft (6) and the second gear shaft (7) is equal to the length between the front side surface and the rear side surface of the main body (1); a limiting slot (9) is respectively provided inside the upper and lower side surfaces of the main body (1), and the extension lines of the upper and lower limiting slots (9) are tangent to the first gear (61), and the upper and lower limiting slots (9) are rotationally symmetrical structures; a limiting slot (9) is also respectively provided inside the left and right side surfaces of the main body (1), and the extension lines of the left and right limiting slots (9) are tangent to the second gear (71), and the left and right limiting slots (9) are rotationally symmetrical structures; The inner sides of the upper support plate (2), the lower support plate (3), the left support plate (4) and the right support plate (5) are all provided with racks (8). The upper support plate (2), the lower support plate (3), the left support plate (4) and the right support plate (5) are respectively located on the outer sides of the upper side, the lower side, the left side and the right side of the main body (1). The racks (8) on the inner sides of the upper support plate (2) and the lower support plate (3) respectively pass through the limiting slots (9) inside the upper side and the lower side of the main body (1) and then mesh with the first gear (61). The racks (8) on the inner sides of the left support plate (4) and the right support plate (5) respectively pass through the limiting slots (9) inside the left side and the right side of the main body (1) and then mesh with the second gear (71).

2. The multi-directional independently adjustable expandable fusion device according to claim 1, characterized in that: The corners of the main body (1) are designed to be in an arc shape.

3. The multi-directional independently adjustable expandable fusion device according to claim 1, characterized in that: The shapes of the upper support plate (2), the lower support plate (3), the left support plate (4), and the right support plate (5) are completely identical to the upper, lower, left, and right sides of the main body (1).

4. The multi-directional independently adjustable expandable fusion device according to claim 1, characterized in that: The inner wall surfaces of the first sleeve (11) and the second sleeve (12) are frosted surfaces.

5. The multi-directional independently adjustable expandable fusion device according to claim 1, characterized in that: The surfaces of the front portion of the first gear shaft (6) and the rear portion of the second gear shaft (7) are both frosted surfaces.

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