Adjustable spinal implant and method of securing

Abstract

The application relates to the field of medical devices, in particular to an adjustable internal spinal column fixer and a fixing method thereof, which comprises a main body, a lifting groove vertically penetrating through the main body, the lifting groove being in sliding cooperation with a T-shaped distance adjusting block and a U-shaped distance adjusting block, a rack one and a rack two being arranged in the T-shaped distance adjusting block and the U-shaped distance adjusting block respectively, and a distance adjusting rotating shaft being rotatably arranged in the lifting groove. In the application, a matched instrument is inserted into a hexagonal groove in the distance adjusting rotating shaft and is matched with the hexagonal groove, then the matched instrument is rotated, the distance adjusting rotating shaft is meshed with the rack one and the rack two on the T-shaped distance adjusting block and the U-shaped distance adjusting block, the rotation of the distance adjusting rotating shaft can drive the T-shaped distance adjusting block and the U-shaped distance adjusting block to move relatively, the T-shaped distance adjusting block and the U-shaped distance adjusting block can support the vertebral body of the affected part, the support mode of injecting bone cement into the vertebral body is replaced, and complications caused by bone cement leakage can be effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to an adjustable spinal internal fixation device and its fixation method. Background Technology

[0002] Currently, the main methods used to treat vertebral compression fractures include PVP (percutaneous vertebroplasty), PKP (kyphoplasty), and vertebroplasty screw fixation. These methods mainly involve using a metal spreader to open up the vertebral body along its long axis and then injecting bone cement to fill and fix it, in order to restore the collapsed vertebral body.

[0003] However, due to the properties of bone cement, leakage is prone to occur during the implantation process. Bone cement leakage is the most common complication in PVP and PKP procedures, which may lead to serious consequences such as lower limb numbness, spinal cord injury, and pulmonary embolism.

[0004] Therefore, given the high risks associated with injecting bone cement into the vertebral body in the existing technologies, developing an adjustable spinal internal fixation device to replace bone cement for vertebral support and fixation is an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing an adjustable spinal internal fixation device and its fixation method, so as to reduce the difficulty of surgery and avoid complications caused by the use of bone cement.

[0006] The objective of this invention can be achieved through the following technical solutions: An adjustable spinal internal fixation device includes a main body, which is a hollow structure. A lifting groove is vertically opened through the main body. The lifting groove slides with a T-shaped adjusting block and a U-shaped adjusting block. A rack and a rack are respectively installed in the T-shaped adjusting block and the U-shaped adjusting block. A cap is rotatably installed at the tail of the main body. A blade retraction groove is opened at the tail of the main body. A C-shaped ring is installed in the blade retraction groove. A connecting piece is provided at the opening of the C-shaped ring. The connecting piece is connected to one end of a spring, and the other end of the spring is connected to the cap. An adjustable shaft is rotatably installed in the lifting groove. Rack 1 and rack 2 respectively mesh with the adjustable shaft. One end of the adjustable shaft is provided with a hexagonal groove. The tail end of the main body is provided with ratchet teeth. The ratchet teeth cooperate with the adjustable shaft. The inside of the screw cap is provided with a toothed groove. The ratchet teeth are located in the toothed groove. The cap has a rotating groove, and a synchronizing ring is rotatably installed in the rotating groove. The synchronizing ring has connecting teeth that mesh with the adjusting shaft. The synchronizing ring has a scale ring, and the cap has an observation groove that passes through one end of the rotating groove.

[0007] As a further optimization or improvement of this solution, one end of the adjustable shaft is coaxially connected to a rotating head, and a second tool relief groove is provided between the adjustable shaft and the rotating head. A retaining ring is installed in the second tool relief groove, and the rotating head is rotatably connected within the main body.

[0008] As a further optimization or improvement of this solution, the tail end of the main body is provided with an irregular groove, and the ratchet is provided with an irregular groove through which a pin and a torsion spring are installed.

[0009] As a further optimization or improvement of this solution, a hexagonal hole is provided through the screw cap, and the area of ​​the hexagonal hole is larger than the area of ​​the hexagonal groove.

[0010] As a further optimization or improvement of this solution, the main body is provided with mating surfaces, which contact the inner walls of the T-shaped adjusting block and the U-shaped adjusting block respectively.

[0011] As a further optimization or improvement to this solution, the top of the main body is designed as a bullet head.

[0012] As a further optimization or improvement of this solution, the sides of the ratchet away from the pitch adjustment shaft are designed with rounded corners and right angles, and the sidewalls of the tooth groove are also designed with rounded corners and right angles, wherein the rounded corners on the ratchet match the rounded corners on the tooth groove.

[0013] A method for fixing an adjustable spinal internal fixator, the method being applied to the adjustable spinal internal fixator as described above, the method comprising the following steps: Step S1: First, make an incision in the patient's back to expose the spinal area that needs to be fixed; Step S2: Using special tools, the entire main body is implanted between the vertebrae that need to be fixed; Step S3: Use the matching instrument to insert it into the hexagonal groove inside the adjusting shaft through the screw cap at the tail end of the main body, so that the matching instrument can cooperate with the adjusting shaft. Step S4: Rotate the matching device to drive the adjusting shaft to rotate. Through the meshing of the adjusting shaft with rack one and rack two, the rotation of the adjusting shaft can drive the T-shaped adjusting block and the U-shaped adjusting block to move relative to each other, thereby causing the T-shaped adjusting block and the U-shaped adjusting block to spread open the vertebral body. At the same time, during the rotation of the adjusting shaft, the teeth on the adjusting shaft will move the ratchet. When the adjusting shaft stops rotating, the ratchet can return to its original position through the mechanical properties of its internal torsion spring, so that the ratchet can limit the adjusting shaft. Step S5: Observe the rotation angle of the adjusting shaft and the distance moved by the T-shaped adjusting block and the U-shaped adjusting block through the scale ring on the synchronization ring.

[0014] The beneficial effects of this invention are: (1) In this invention, by inserting a matching device into the hexagonal groove of the adjusting shaft and engaging with it, and then rotating the matching device, the adjusting shaft can drive the T-shaped adjusting block and the U-shaped adjusting block to move relative to each other due to the meshing of the adjusting shaft with the racks 1 and 2 on the T-shaped adjusting block and the U-shaped adjusting block. This allows the T-shaped adjusting block and the U-shaped adjusting block to support the vertebral body at the affected area, thereby replacing the support method of injecting bone cement into the vertebral body and effectively avoiding complications caused by bone cement leakage. When the T-shaped adjusting block and the U-shaped adjusting block support the vertebral body at the affected area to a normal state, the ratchet, through its internal torsion spring mechanical properties, can return the ratchet to its original position and limit the adjusting shaft. At this time, by limiting the adjusting shaft through the ratchet, the reverse rotation of the adjusting shaft can be restricted, thus effectively avoiding the phenomenon of fixation failure.

[0015] (2) In this invention, by rotating the adjusting shaft by one tooth, the T-shaped adjusting block and the U-shaped adjusting block can move up and down by one tooth distance respectively. The distance moved by the T-shaped adjusting block and the U-shaped adjusting block is set as a unit distance and engraved on the scale ring. When the adjusting shaft rotates, the adjusting shaft will rotate with the synchronization ring at the same time. At this time, the moving distance of the T-shaped adjusting block and the U-shaped adjusting block can be observed from the observation slot, which facilitates the measurement of the vertebral body opening distance during surgery and reduces the requirements of surgery and doctor's experience.

[0016] (3) In this invention, when the T-shaped and U-shaped adjusting blocks are retracted into the main body, the T-shaped adjusting block can be completely inserted into the U-shaped adjusting block and cooperate with it, reducing the space occupied by the T-shaped and U-shaped adjusting blocks, thus reducing the overall volume of the main body and facilitating its implantation. The surfaces of the T-shaped and U-shaped adjusting blocks that contact the vertebral body are coated with a titanium coating, so that after the T-shaped and U-shaped adjusting blocks are implanted into the human body, the porous structure of the titanium coating can fuse with the bone. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 This is a diagram showing the connection between the adjustable pivot and the main body.

[0020] Figure 3 This is a diagram showing the connection between the C-ring and the spring.

[0021] Figure 4 This is an exploded view of the overall structure.

[0022] Figure 5 This is a schematic diagram of the ratchet groove and the ratchet tooth.

[0023] Figure 6 This is a connection diagram of the synchronization ring and the adjustable shaft.

[0024] Figure 7 This is a diagram showing the fit between the screw cap and the synchronizing ring.

[0025] Figure 8 This is a diagram showing the fit between the scale ring and the observation groove.

[0026] The following are marked in the diagram: 1. Main body; 2. T-shaped adjusting block; 3. U-shaped adjusting block; 4. Screw cap; 5. Lifting groove; 6. Mating surface; 7. C-shaped ring; 8. Spring; 9. Retraction groove one; 10. Adjusting shaft; 11. Ratchet; 12. Torsion spring; 13. Pin; 14. Retraction groove two; 15. Rotating head; 16. Hexagonal groove; 17. Hexagonal hole; 18. Observation groove; 19. Snap ring; 20. Tooth groove; 21. Rotating groove; 22. Synchronizing ring; 23. Connecting tooth; 24. Irregular groove; 25. Scale ring; 26. Connecting piece; 27. Rack two; 28. Rack one. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] See Figures 1-8 An adjustable spinal internal fixation device includes a main body 1, which is a hollow structure. A lifting groove 5 is vertically opened through the main body 1. The lifting groove 5 is slidably engaged with a T-shaped adjusting block 2 and a U-shaped adjusting block 3. A rack 28 and a rack 27 are respectively provided in the T-shaped adjusting block 2 and the U-shaped adjusting block 3. A cap 4 is rotatably installed at the tail of the main body 1. A blade retraction groove 9 is opened at the tail of the main body 1. A C-shaped ring 7 is installed in the blade retraction groove 9. A connecting piece 26 is provided at the opening of the C-shaped ring 7. The connecting piece 26 is connected to one end of a spring 8. The other end of the spring 8 is connected to the cap 4. An adjustable shaft 10 is rotatably installed in the lifting groove 5. Rack 1 28 and rack 2 27 respectively mesh with the adjustable shaft 10. One end of the adjustable shaft 10 is provided with a hexagonal groove 16. The tail end of the main body 1 is provided with a ratchet 11. The ratchet 11 cooperates with the adjustable shaft 10. The inside of the screw cap 4 is provided with a tooth groove 20. The ratchet 11 is located in the tooth groove 20. The screw cap 4 has a rotating groove 21, and the synchronizing ring 22 is rotatably installed in the rotating groove 21. The synchronizing ring 22 is provided with connecting teeth 23, which mesh with the adjusting shaft 10. The synchronizing ring 22 is provided with a scale ring 25, and the screw cap 4 has an observation groove 18 that passes through one end of the rotating groove 21.

[0029] It should be noted that rack 1 28 and rack 2 27 are installed in opposing positions inside U-shaped adjusting block 3 and T-shaped adjusting block 2. When T-shaped adjusting block 2 and U-shaped adjusting block 3 are inside the main body 1, T-shaped adjusting block 2 can be inserted into U-shaped adjusting block 3 and cooperate with U-shaped adjusting block 3, reducing the space occupied by T-shaped adjusting block 2 and U-shaped adjusting block 3. At the same time, the surfaces of T-shaped adjusting block 2 and U-shaped adjusting block 3 that contact the vertebral body are coated with titanium coating, so that after T-shaped adjusting block 2 and U-shaped adjusting block 3 are implanted into the human body, the porous structure of the titanium coating can fuse with the bone, which is suitable for younger patients and allows for adjustment of the intervertebral distance according to the development. The last tooth of rack 27 and rack 28 is higher than the other teeth. The purpose of this is to limit the movement distance of T-shaped adjusting block 2 and U-shaped adjusting block 3, and to prevent T-shaped adjusting block 2 and U-shaped adjusting block 3 from extending too far, which would cause T-shaped adjusting block 2 and U-shaped adjusting block 3 to detach from the main body 1 or adjusting shaft 10, resulting in the inability to retract T-shaped adjusting block 2 and U-shaped adjusting block 3.

[0030] It should be noted that during the operation, when the rotating adjustment shaft 10 drives the T-shaped adjustment block 2 and the U-shaped adjustment block 3 to support the vertebral body, it is not possible to directly observe the movement distance of the T-shaped adjustment block 2 and the U-shaped adjustment block 3. Therefore, the doctor needs to subjectively estimate the adjustment distance of the T-shaped adjustment block 2 and the U-shaped adjustment block 3 by visual inspection, which requires a high level of surgical experience from the doctor and makes the operation more difficult.

[0031] Therefore, to solve the above problem, the T-shaped adjusting block 2 and the U-shaped adjusting block 3 can move up and down by one tooth distance with each rotation of the adjusting shaft 10. The distance moved by the T-shaped adjusting block 2 and the U-shaped adjusting block 3 is the unit distance. This unit distance is marked on the scale ring 25. When the adjusting shaft 10 rotates, the adjusting shaft 10 will also rotate with the synchronization ring 22. At this time, the movement distance of the T-shaped adjusting block 2 and the U-shaped adjusting block 3 can be observed from the observation slot 18, which facilitates the measurement of the vertebral body opening distance during surgery and reduces the requirements of surgery.

[0032] See Figure 4One end of the adjusting shaft 10 is coaxially connected to a rotating head 15. A tool relief groove 14 is provided between the adjusting shaft 10 and the rotating head 15. A retaining ring 19 is installed in the tool relief groove 14. The rotating head 15 is rotatably connected within the main body 1. It should be noted that the retaining ring 19 has a cylindrical overall structure. The outer diameter of the retaining ring 19 is slightly larger than the hollow hole of the main body 1. The through hole of the retaining ring 19 is smaller than the outer diameter of the rotating head 15, but must be larger than the outer diameter of the tool relief groove 14. When assembling the rotating head 15, the retaining ring 19 is first pressed into the tool relief groove 14, and then the rotating head 15 together with the retaining ring 19 is assembled into the main body 1. When the retaining ring 19 is inserted into the main body, it is squeezed and undergoes elastic deformation. At this time, the size of the retaining ring 19 is smaller than its original state, thus completing the assembly of the adjusting shaft 10.

[0033] See Figure 4 The tail end of the main body 1 is provided with a shaped groove 24, and the ratchet 11 is provided with a through shaped groove 24. A pin 13 and a torsion spring 12 are installed in the shaped groove 24. It should be noted that the tail end of the main body 1 and the ratchet 11 are provided with the same shaped groove 24 to facilitate the assembly of the ratchet 11.

[0034] See Figure 2 The cap 4 has a hexagonal hole 17 through it, and the area of ​​the hexagonal hole 17 is larger than the area of ​​the hexagonal groove 16. It should be noted that the rotation of the adjusting shaft 10 requires the insertion of a corresponding instrument into the hexagonal groove 16. The rotation of the adjusting shaft 10 is controlled by rotating the matching instrument. The cap 4 is used to control the reverse rotation of the adjusting shaft 10. In order to prevent the rotation of the adjusting shaft 10 from causing the cap 4 to rotate, the area of ​​the hexagonal hole 17 must be larger than the area of ​​the hexagonal groove 16, so as to ensure that the rotation of the adjusting shaft 10 will not interfere with the movement of the cap 4.

[0035] See Figure 2 The main body 1 has mating surfaces 6, which contact the inner walls of the T-shaped adjusting block 2 and the U-shaped adjusting block 3. It should be noted that when the T-shaped adjusting block 2 and the U-shaped adjusting block 3 are completely retracted into the main body 1, they abut against the mating surfaces 6. At this time, the T-shaped adjusting block 2 and the U-shaped adjusting block 3 located inside the main body 1 can fully engage, reducing their space occupancy and thus decreasing the volume of the main body 1, thereby improving the product's precision.

[0036] See Figures 1-4The top of the main body 1 is designed like a bullet. It should be noted that all components of this invention are machined from titanium alloy (TC4), a material known for its stable properties and non-chemical reactions that could damage human nerves and tissues. The overall shape of the main body 1 is a bullet-like structure. This design facilitates easy implantation into the vertebral body, improves the product's lightweight nature, and simplifies the implantation process, reducing surgical steps and significantly shortening the operation time and minimizing the need for experienced surgeons.

[0037] See Figure 5 The ratchet 11 has rounded and right-angled designs on its side away from the adjustment shaft 10. The sidewall of the tooth groove 20 also has rounded and right-angled designs, with the rounded corners on the ratchet 11 matching the rounded corners on the tooth groove 20.

[0038] It should be noted that when it is necessary to rotate the adjusting shaft 10 in the reverse direction to move the T-shaped adjusting block 2 and the U-shaped adjusting block 3 into the lifting groove 5, rotate the cover 4 so that the rounded corner of the inner wall of the tooth groove 20 contacts the rounded corner on the ratchet 11. Then continue to rotate the cover 4 so that the rounded corner on the inner wall of the tooth groove 20 drives the ratchet 11 to rotate and disengage the ratchet 11 from the adjusting shaft 10. At this time, rotate the adjusting shaft 10 in the reverse direction to retract the T-shaped adjusting block 2 and the U-shaped adjusting block 3 into the main body 1. Release the cover 4, and the spring 8 will rebound and drive the cover 4 back to its original position. At this time, the rounded corner on the tooth groove 20 disengages from the ratchet 11, and the ratchet 11 returns to the state of abutting the adjusting shaft 10 under the mechanical characteristics of the torsion spring 12.

[0039] See Figures 1-8 As shown, the present invention provides a fixation method for an adjustable spinal internal fixator. The method is applied to the adjustable spinal internal fixator described in the above embodiment and includes the following steps: Step S1: First, make an incision in the patient's back to expose the spinal area that needs to be fixed; Step S2: Using special tools, the main body 1 is implanted as a whole between the vertebrae that need to be fixed; Step S3: Use the matching instrument to insert the screw cap 4 at the tail end of the main body 1 into the hexagonal groove 16 inside the adjusting shaft 10, so that the matching instrument can cooperate with the adjusting shaft 10. Step S4: Rotate the matching device to drive the adjusting shaft 10 to rotate. Through the meshing of the adjusting shaft 10 with rack 28 and rack 27, the rotation of the adjusting shaft 10 can drive the T-shaped adjusting block 2 and U-shaped adjusting block 3 to move relative to each other, thereby opening the T-shaped adjusting block 2 and U-shaped adjusting block 3 to the vertebral body. At the same time, during the rotation of the adjusting shaft 10, the teeth on the adjusting shaft 10 will move the ratchet 11. When the adjusting shaft 10 stops rotating, the ratchet 11 can return to its original position through the mechanical properties of its internal torsion spring 12, so that the ratchet 11 can limit the adjusting shaft 10. Step S5: Observe the rotation angle of the adjusting shaft 10 and the distance moved by the T-shaped adjusting block 2 and the U-shaped adjusting block 3 through the scale ring 25 on the synchronization ring 22.

[0040] The principle of this invention is as follows: During surgery, the main body 1 is first inserted into the vertebrae that need to be opened by means of the bullet-shaped design at the top of the main body 1. Then, a matching instrument is inserted into the hexagonal groove 16 in the adjusting shaft 10 through the hexagonal hole 17, so that the matching instrument can cooperate with the adjusting shaft 10. At this time, rotating the matching instrument will drive the adjusting shaft 10 to rotate. When the adjusting shaft 10 is engaged with the rack 28 and rack 27, the rotation of the adjusting shaft 10 can drive the T-shaped adjusting block 2 and the U-shaped adjusting block 3 to move relative to each other, thereby opening the vertebrae with the T-shaped adjusting block 2 and the U-shaped adjusting block 3. Simultaneously, during the rotation of the pitch adjustment shaft 10, the teeth on the pitch adjustment shaft 10 will engage the ratchet 11. When the pitch adjustment shaft 10 stops rotating, the ratchet 11, through the mechanical properties of its internal torsion spring 12, can return to its original position, thereby allowing the ratchet 11 to be inserted between the teeth on the pitch adjustment shaft 10 and limit the pitch adjustment shaft 10. At this time, by limiting the pitch adjustment shaft 10 through the ratchet 11, the reverse rotation of the pitch adjustment shaft 10 can be restricted, thereby preventing the T-shaped pitch adjustment block 2 and the U-shaped pitch adjustment block 3 from being compressed by the cone body and causing the pitch adjustment shaft 10 to rotate, which would lead to the failure of the fixing function of the present invention.

[0041] During the rotation of the adjusting shaft 10, each rotation of the adjusting shaft 10 causes the T-shaped adjusting block 2 and the U-shaped adjusting block 3 to move up and down by one tooth distance. The distance moved by the T-shaped adjusting block 2 and the U-shaped adjusting block 3 is the unit distance, which is marked on the scale ring 25. When the adjusting shaft 10 rotates, the adjusting shaft 10 will also rotate with the synchronization ring 22. At this time, the movement distance of the T-shaped adjusting block 2 and the U-shaped adjusting block 3 can be observed from the observation groove 18, which facilitates the measurement of the vertebral body opening distance during surgery.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An adjustable spinal internal fixation device, characterized in that, It includes a main body (1), which is a hollow structure. A lifting groove (5) is vertically opened on the main body (1). The lifting groove (5) is slidably engaged with a T-shaped adjusting block (2) and a U-shaped adjusting block (3). A rack (28) and a rack (27) are respectively provided in the T-shaped adjusting block (2) and the U-shaped adjusting block (3). A screw cap (4) is rotatably installed at the tail of the main body (1). A knife relief groove (9) is opened at the tail of the main body (1). A C-shaped ring (7) is installed in the knife relief groove (9). A connecting piece (26) is provided at the opening of the C-shaped ring (7). The connecting piece (26) is connected to one end of a spring (8), and the other end of the spring (8) is connected to the screw cap (4). An adjustable shaft (10) is rotatably installed in the lifting groove (5). Rack 1 (28) and rack 2 (27) mesh with the adjustable shaft (10) respectively. A hexagonal groove (16) is opened at one end of the adjustable shaft (10). A ratchet (11) is installed at the tail end of the main body (1). The ratchet (11) cooperates with the adjustable shaft (10). A toothed groove (20) is opened inside the screw cap (4). The ratchet (11) is located in the toothed groove (20). The screw cap (4) has a rotating groove (21) inside, and the synchronizing ring (22) is rotatably installed inside the rotating groove (21). The synchronizing ring (22) has a connecting tooth (23) that meshes with the adjusting shaft (10). The synchronizing ring (22) has a scale ring (25), and the screw cap (4) has an observation groove (18) that passes through one end of the rotating groove (21). The tail end of the main body (1) is provided with a groove (24), and the groove (24) is provided through the ratchet (11). A pin (13) and a torsion spring (12) are installed in the groove (24). The ratchet (11) has a rounded corner design and a right angle design on the side away from the adjustment shaft (10), and the side wall of the tooth groove (20) also has a rounded corner and a right angle design, wherein the rounded corner on the ratchet (11) matches the rounded corner on the tooth groove (20).

2. The adjustable spinal internal fixation device according to claim 1, characterized in that: One end of the adjustable shaft (10) is coaxially connected to a rotating head (15). A tool relief groove (14) is provided between the adjustable shaft (10) and the rotating head (15). A retaining ring (19) is installed in the tool relief groove (14). The rotating head (15) is rotatably connected within the main body (1).

3. The adjustable spinal internal fixation device according to claim 1, characterized in that, The cap (4) has a through-hole (17) with an area larger than that of the hexagonal groove (16).

4. An adjustable spinal internal fixation device according to claim 1, characterized in that, The main body (1) has a mating surface (6) which contacts the inner walls of the T-shaped adjusting block (2) and the U-shaped adjusting block (3).

5. An adjustable spinal internal fixation device according to claim 1, characterized in that, The top of the main body (1) is designed like a bullet.

Images