A variable stiffness fixation rod for spinal surgery

Abstract

The present invention provides a variable stiffness fixation rod for spinal surgery, which belongs to the technical field of spinal surgical medical devices. It includes a first fixation rod connected to a second fixation rod, and a stiffness adjustment component and a supplementary component are installed on the second fixation rod. Before the stiffness adjustment component is dissolved, the supplementary component is pressed between the second fixation rod and the stiffness adjustment component, and the stiffness adjustment component increases the stiffness of the fixation rod; after the stiffness adjustment component is dissolved, the stiffness of the fixation rod is relatively reduced, and the stiffness adjustment component realizes stiffness adjustment. The supplementary component is pressed between the second fixation rod and the pedicle steel screw and the locking screw plug, offsetting the gap generated after the stiffness adjustment component is dissolved, and the supplementary component enables the pedicle steel screw and the locking screw plug to lock the second fixation rod; it is used to adjust the stiffness of the second fixation rod during use. It improves the joint mobility of the auxiliary fixation segment of the patient's spine, reduces the force of the internal fixation system, and reduces the risk of adjacent segment degeneration and internal fixation system failure.

Description

Technical Field

[0001] The invention relates to the technical field of spinal surgery medical instruments, and in particular to a variable stiffness fixation rod for spinal surgery. Background Art

[0002] Thoracolumbar compression fractures generally refer to compression of the front half of the vertebral body (anterior column) caused by flexion force, while the vertebral arch (posterior column) at the back of the spine is normal. A few cases have traction injuries. The vertebral body usually becomes wedge-shaped, which is a common type of injury in spinal fractures. When thoracolumbar compression fractures are severe, spinal fixation surgery is required as a treatment method. This is a surgery that maintains the stability of the spine through internal fixation. It uses a nail rod system to fix the unstable spine.

[0003] In the prior art, when a nail-rod system is used to fix an unstable spine, the fixation nails are driven into the spine, and then the adjacent fixation nails are connected using a fixation rod. The fixation rod is a relatively common cylindrical rod or rectangular rod, which is embedded in the top of the fixation nail and then tightened with bolts to achieve the installation of the fixation rod. However, since the spinal fixation segment is fixed with a nail-rod system, the joint mobility of the fixed segment is much smaller than the normal value, and the reduction in joint mobility will lead to increased stress in adjacent segments, and will also increase the force of the internal fixation system, resulting in an increased risk of adjacent segment degeneration and failure of the internal fixation system. Therefore, the present application provides a variable stiffness fixation rod for spinal surgery to meet the needs. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a variable stiffness fixation rod for spinal surgery to solve the problem that the use of a nail-rod system in existing spinal fixation surgery causes the joint mobility of the fixed joint to be far lower than the normal value, resulting in increased stress in adjacent segments and increased force in the internal fixation system, leading to an increased risk of adjacent segment degeneration and failure of the internal fixation system.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A variable stiffness fixation rod for spinal surgery, comprising:

[0007] A first fixing rod and a second fixing rod, one end of the second fixing rod is connected to the first fixing rod, two fixing grooves arranged opposite to each other are provided on the outer wall of the other end of the second fixing rod, a protruding mounting portion is provided on the outer side of the circumference of the second fixing rod, mounting protrusions are provided at both ends of the mounting portion, two groups of limiting grooves are formed on the outer side of the mounting portion, and a matching groove is provided on the mounting portion;

[0008] A stiffness adjustment component, wherein the stiffness adjustment component is sleeved on the second fixing rod and the stiffness adjustment component adjusts the stiffness of the second fixing rod during use;

[0009] A supplementary component is installed in the fixing groove of the second fixing rod, and the supplementary component is pressed against the stiffness adjustment component. After the stiffness adjustment component is dissolved, the supplementary component supplements the gap between the stiffness adjustment component and the pedicle screw, and the gap between the stiffness adjustment component and the locking screw plug. The supplementary component is connected to the second fixing rod.

[0010] Optionally, the stiffness adjustment component includes an adjustment sleeve, the adjustment sleeve includes a circular ring portion and a fixed portion, a positioning groove is provided on the end of the circular ring portion close to the fixed portion, and two groups of fixing blocks are provided on the fixed portion, the shapes of the two groups of fixing blocks are adapted to the shapes of the two groups of limiting grooves on the mounting portion, and the adjustment sleeve and the fixing blocks are both made of medical magnesium alloy.

[0011] Optionally, the supplementary component includes a pair of first elastic plates fixedly connected to the bottom of the fixing groove of a second fixing rod, the outer walls of the pair of first elastic plates are fixedly connected to the same first abutment plate, a pair of second elastic plates and a pair of third elastic plates are fixedly connected in the fixing groove of another second fixing rod, the top of each second elastic plate and each third elastic plate is fixedly connected to the same second abutment plate, the opposite sides of a pair of second abutment plates are fixedly connected to the same connecting plate, a pair of second elastic plates and a pair of third elastic plates are symmetrically arranged on both sides of the connecting plate, the second elastic plate is located on the side away from the connecting plate, the third elastic plate is located on the side close to the connecting plate, and the first elastic plate has a V-shaped structure.

[0012] Optionally, the mounting protrusion is in a semicircular structure, and a transition plate is fixedly connected to a connection between the mounting protrusion and the first fixing rod.

[0013] Optionally, the arrangement density of the limiting grooves increases from low to high from the two ends of the mounting portion to the middle position, and the size of the limiting grooves increases from high to low from the two ends of the mounting portion to the middle position.

[0014] Optionally, the matching groove includes a plurality of arc grooves, two adjacent arc grooves are connected by a rectangular groove, and the sizes of the plurality of arc grooves are arranged from small to large from the two ends of the installation to the middle position.

[0015] Optionally, the stiffness adjustment component further includes a connecting block, which is installed in the matching groove and is made of medical magnesium alloy.

[0016] Optionally, the second elastic plate and the third elastic plate are both V-shaped structures, the connecting plate is V-shaped structure, the bending part of the V-shaped structure is an arc structure, and the thickness of the connecting plate is smaller than the thickness of the second abutting plate.

[0017] Optionally, the second abutment plate includes a first limit plate and a second limit plate connected to each other, a weakening groove is provided at the connection between the first limit plate and the second limit plate, one end of the first limit plate is fixedly connected to the first arc plate and the second arc plate connected to each other, and one end of the second limit plate is fixedly connected to the third arc plate.

[0018] Optionally, the arc directions of the first arc plate and the second arc plate are opposite, and the arc directions of the first arc plate and the third arc plate are the same, both of which are convex towards a direction away from the outer wall of the second abutting plate.

[0019] Compared with the prior art, the embodiments of the present invention have at least the following beneficial effects:

[0020] In the above scheme, by setting up the stiffness adjustment component, during the patient's postoperative recovery process, as time goes by, the stiffness adjustment component is gradually absorbed, and the stiffness of the fixation rod of the auxiliary fixation segment gradually decreases, so that the stiffness of the fixation rod can be adjusted, thereby improving the joint mobility of the patient's spinal auxiliary fixation segment, reducing the force of the internal fixation system, and reducing the risk of adjacent segment degeneration and internal fixation system failure.

[0021] By setting up the supplementary component, when the stiffness adjustment component is completely absorbed by the patient's body, the supplementary component can supplement the gap between the second fixing rod and the vertebral arch steel screw, and the gap between the second fixing rod and the locking screw plug, thereby improving the stability of the second fixing rod in subsequent use.

[0022] The adjusting sleeve, fixing block and connecting block in the stiffness adjusting assembly are respectively matched with the mounting groove, limiting groove and matching groove on the second fixing rod. During the use of the second fixing rod, the adjusting sleeve, fixing block and connecting block can be absorbed by the patient's body, and cooperate with the shape structure of the limiting groove and matching groove, so that the stiffness of both ends of the second fixing rod gradually weakens toward the middle, thereby improving the range of motion of the auxiliary fixation segment joint of the spine and improving the stability of the connection between the end of the second fixing rod close to the first fixing piece and the pedicle screw.

[0023] The second abutment plate and the first abutment plate provided in the supplementary component respectively cooperate with the second elastic plate, the third elastic plate and the first elastic plate, and cooperate with the adjustment sleeve provided in the stiffness adjustment component. When the adjustment sleeve is absorbed by the patient's body, under the action of the elastic force of the second elastic plate, the third elastic plate and the first elastic plate, the second abutment plate and the first abutment plate respectively abut against the bottom and threaded surface of the locking screw plug and the bottom of the inner wall of the steel nail groove of the pedicle steel nail, thereby ensuring that the second fixing rod will not move during the activity process to cause the internal fixation system to fail, thereby further improving the stability of the internal fixation system.

[0024] After the connecting block is absorbed by the patient's body, the matching groove on the second fixing rod is exposed, and the matching groove fits with the patient's spinal surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, further serve to explain the principles of the invention and to enable those skilled in the relevant art to make and use the invention.

[0026] Figure 1 A schematic diagram of the three-dimensional structure of a variable stiffness fixation rod for spinal surgery from a first-person perspective;

[0027] Figure 2 A schematic diagram of the third dimension structure of a variable stiffness fixation rod for spinal surgery from a second perspective;

[0028] Figure 3 A partially cutaway three-dimensional structure diagram of a variable stiffness fixation rod for spinal surgery;

[0029] Figure 4 A schematic diagram of a partial side view of the second fixing rod and the supplementary assembly assembly;

[0030] Figure 5 A schematic diagram of a three-dimensional structure for assembling a second fixing rod and a supplementary component;

[0031] Figure 6 It is a schematic diagram of the three-dimensional structure of the adjustment sleeve and the connection block;

[0032] Figure 7 A schematic diagram of the three-dimensional structure of a variable stiffness fixation rod and a pedicle screw for spinal surgery;

[0033] Figure 8 Schematic diagram of the matching position of the locking screw plug and the supplementary component.

[0034] [reference numerals]

[0035] 1. First fixing rod; 2. Second fixing rod; 3. Mounting protrusion; 4. Limiting groove; 5. Fixing groove; 6. Matching groove; 7. Adjusting sleeve; 71. Fixing part; 72. Circular ring part; 73. Mounting groove; 8. Positioning groove; 9. Fixing block; 10. Connecting block; 11. Transition plate; 12. Arc groove; 13. Rectangular groove; 14. First elastic plate; 15. First abutting plate; 16. Second elastic plate; 17. Third elastic plate plate; 18, second abutment plate; 19, connecting plate; 20, first limiting plate; 21, mounting portion; 22, weakened groove; 23, first arc plate; 24, second arc plate; 25, third arc plate; 26, vertebral arch steel nail; 261, steel nail groove; 27, locking screw plug; 271, threaded surface; 272, bottom of locking screw plug; 28, auxiliary fixing segment; 29, main fixing segment; 30, second limiting plate.

[0036] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0037] The following is a detailed description of a variable stiffness fixation rod for spinal surgery provided by the present invention in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternative methods to implement some known technologies; and the accompanying drawings are only for a more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0038] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0039] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0040] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” not only means “directly on” something, but also includes the meaning of being “on” something with intervening features or layers therebetween, and “on” or “over” not only means “on” or “above” something, but also includes the meaning of being “on” or “above” something with no intervening features or layers therebetween.

[0041] Additionally, spatially relative terms such as "under," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as shown in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein may be similarly interpreted accordingly.

[0042] like Figures 1 to 8 As shown, an embodiment of the present invention provides a variable stiffness fixation rod for spinal surgery, comprising a first fixation rod 1, a second fixation rod 2 is fixedly connected to one side of the first fixation rod 1, a protruding mounting portion 21 is arranged on the circumferential outer side of the second fixation rod 2, two groups of limiting grooves 4 are formed on the outer side of the mounting portion 21, mounting protrusions 3 are arranged at both ends of the mounting portion 21, one of the mounting protrusions 3 is close to the first fixation rod 1, and the other mounting protrusion 3 is close to the end of the mounting portion 21, a plurality of limiting grooves 4 are provided, and the arrangement density of the limiting grooves 4 changes from low to high from the two ends of the mounting portion 21 to the middle position, and the limiting grooves 4 are arranged in a plurality of positions. The size of the position slot 4 is arranged from high to low from the two ends of the mounting portion 21 to the middle position. The mounting protrusion 3 is a semicircular structure. The mounting protrusion 3 close to the first fixing rod 1 is connected to the transition plate 11. The first fixing rod 1 and the second fixing rod 2 are connected through the mounting protrusion 3 close to the first fixing rod 1 and the transition plate 11. A matching groove 6 is opened on the mounting portion 21. The matching groove 6 includes a plurality of arc grooves 12. Two adjacent arc grooves 12 are connected by a rectangular groove 13. The sizes of the plurality of arc grooves 12 on the mounting portion 21 are arranged from small to large from the two ends of the mounting portion 21 to the middle position.

[0043] like Figure 3 and Figure 4 As shown, Figure 3 The adjusting sleeve 7 is cut open to expose the position of the supplementary component and the second fixing rod 2 at the position of the supplementary component. The outer wall of one end of the second fixing rod 2 is provided with two fixing grooves 5 arranged opposite to each other.

[0044] like Figure 5 As shown, the stiffness adjustment assembly includes an adjustment sleeve 7 and a connecting block 10. The adjustment sleeve 7 includes a circular ring portion 72 and a fixed portion 71. A positioning groove 8 is provided on the end of the circular ring portion 72 close to the fixed portion 71. Two groups of fixing blocks 9 are provided on the fixed portion 71. The shapes of the two groups of fixing blocks 9 are adapted to the shapes of the two groups of limiting grooves 4 on the mounting portion 21. The shape of the connecting block 10 is adapted to the shape of the matching groove 6, so that the connecting block 10 can be installed in the matching groove 6.

[0045] like Figure 2 and Figure 5As shown, the second fixing rod 2 is inserted into the adjusting sleeve 7, and the mounting portion 21 is buckled on the second fixing rod 2. The mounting portion 21 cooperates with the fixing portion 72 of the adjusting sleeve 7, so that the fixing block 9 of the adjusting sleeve 7 is inserted into the limiting groove 4 of the mounting portion 21, and the mounting protrusion of the mounting portion 21 enters and exits the mounting groove 73 of the adjusting sleeve 7. The connecting block 10 is embedded in the matching groove 6 of the mounting portion 21. The materials of the connecting block 10, the adjusting sleeve 7 and the fixing block 9 are all made of medical magnesium alloy. Before the connecting block 10 is absorbed by the patient's body, the connecting block 10 increases the rigidity of the second fixing rod 2. After the connecting block 10 is absorbed by the patient's body, the matching groove 6 on the second fixing rod 2 is exposed, and the matching groove 6 fits the patient's spinal surface.

[0046] A stiffness adjustment component, which is used to adjust the stiffness of the second fixing rod 2 during use. The stiffness adjustment component and the sleeve are arranged on the mounting portion 21 of the second fixing rod 2; a supplementary component, which is used to supplement the gap between the adjustment sleeve 7 and the vertebral arch steel screw 26, and the gap between the adjustment sleeve 7 and the locking screw plug 27 to ensure the stability of the second fixing rod 2 during use. The supplementary component is installed on the second fixing rod 2.

[0047] By setting the stiffness adjustment component, when a spinal fixation operation is needed for a patient, the cone steel screw is first driven into a suitable position of the patient's spine, and the variable stiffness fixation rod designed by the present invention is clamped into the steel screw groove 261 of the vertebral arch steel screw 26, so that the first fixation rod 1 is set in the main spinal fixation segment 29, the second fixation rod 2, the stiffness adjustment component and the supplementary component are all set in the auxiliary fixation segment 28, and the fixing rod and the vertebral arch steel screw 26 are fixed by the locking screw plug 27. The fixation rod used in the spinal auxiliary fixation segment 28 just after the operation is completed has the highest strength, and the subsequent patients During the recovery process, the stiffness adjustment component can adjust the stiffness of the fixing rod of the auxiliary fixation segment 28 over time, thereby improving the joint mobility of the patient's spinal auxiliary fixation segment 28 and reducing the force of the internal fixation system. At the same time, when the stiffness adjustment component on the second fixing rod 2 is completely absorbed by the patient's body, the supplementary component can supplement the gap between the second fixing rod 2 and the vertebral arch steel screw 26 and the locking screw plug 27, thereby improving the stability of the second fixing rod 2 in subsequent use and effectively reducing the risk of adjacent segment degeneration and internal fixation system failure.

[0048] The adjusting sleeve 7, fixing block 9 and connecting block 10 are respectively matched with the matching groove 6 on the second fixing rod 2 and the mounting protrusion 3, the limiting groove 4 and the matching groove 6 on the mounting portion 21, wherein the mounting protrusion 3 is a semicircular structure, and the transition plate 11 smoothly fixed at the connection between one end of the mounting protrusion 3 and the first fixing rod 1 improves the stability of the connection between the second fixing rod 2 and the first fixing rod 1. The adjusting sleeve 7, fixing block 9 and connecting block 10 are all made of medical magnesium alloy and can be absorbed by the patient's body. During the patient's postoperative and recovery process, the adjusting sleeve 7, fixing block 9 and connecting block 10 have not been absorbed by the patient's body just after the operation. At this time, the rigidity of the entire fixing rod is the highest. During the recovery process, The mounting portion 21, the adjustment sleeve 7, and the fixing block 9 will gradually be absorbed by the patient's body, thereby completely exposing the second fixing rod 2 of the auxiliary fixing segment 28. The corresponding position of the mounting protrusion 3 on the second fixing rod 2 makes the thickness of the second fixing rod 2 away from the patient's spinal surface thinner, thereby reducing the rigidity, thereby improving the range of motion of adjacent joints. The matching groove 6 of the second fixing rod 2 is aligned with the patient's spinal surface, and the matching groove 6 of the second fixing rod 2 fits with the patient's spinal surface. After the second fixing rod 2 is provided with the matching groove 6, the rigidity of the second fixing rod 2 is second only to that of the first fixing rod 1. During the recovery process of the patient, the spine of the auxiliary fixing segment 28 has good mobility, and will not be injured during activity due to excessive reduction in rigidity. At the same time, the arrangement density of the limiting grooves 4 changes from low to high from the two ends of the mounting portion 21 to the middle position, and the size of the limiting grooves 4 changes from high to low from the two ends of the mounting portion 21 to the middle position, and then cooperates with the matching grooves 6. The matching grooves 6 include a plurality of connected arc grooves 12 and rectangular grooves 13. The sizes of the plurality of arc grooves 12 are arranged from small to large from the two ends of the second fixing rod 2 to the middle position. This arrangement and combination method cooperates with the mounting protrusion 3 to make the stiffness of the second fixing rod 2 change from strong to weak from its two ends to the middle. The stiffness of the second fixing rod 2 gradually weakens from the two ends to the middle. The stiffness of the second fixing rod 2 connected to the end of the first fixing rod 1 is relatively strong. A pedicle steel screw 26 is installed on the second fixing rod 2 near the first fixing rod 1. While improving the joint activity of the spinal auxiliary fixation segment 28, the stability of the connection between the end of the second fixing rod 2 near the first fixing rod 1 and the pedicle steel screw 26 is effectively improved.

[0049] like Figure 6 As shown, the supplementary assembly includes a pair of first elastic plates 14, a pair of second elastic plates 16 and a pair of third elastic plates 17. A pair of first elastic plates 14 is installed in one fixing groove 5, and a pair of second elastic plates 16 and a pair of third elastic plates 17 are installed in another fixing groove 5. Specifically, one end of the first elastic plate 14 is fixedly connected to the bottom of the inner wall of the fixing groove 5, and the other end is fixedly connected to the first abutting plate 15, so that the first elastic plate 14 is connected to the same first abutting plate 15. Specifically, the first elastic plate 14 is in a V-shaped structure.

[0050] For example Figure 6 As shown, one end of the second elastic plate 16 and the third elastic plate 17 are both fixedly connected to the bottom of the inner wall of the fixing groove 5, and the other end is fixedly connected to the second abutting plate 18, so that the second elastic plate 16 and the third elastic plate 17 are connected to the same second abutting plate 18. Specifically, the second abutting plate 18 includes a first limiting plate 20 and a second limiting plate 30 connected, a weakening groove 22 is provided at the connection between the first limiting plate 20 and the second limiting plate 30, one end of the first limiting plate 20 is provided with a first curved plate 23 and a second curved plate 24 connected, and one end of the second limiting plate 30 is provided with a third curved plate 25, the arcs of the first curved plate 23 and the second curved plate 24 are in opposite directions, the arcs of the first curved plate 23 and the third curved plate 25 are in the same direction, and both are protruding in the direction away from the outer wall of the second abutting plate 18, and a pair of second abutting plates 18 are connected by a connecting plate 19. Specifically, the second elastic plate 16 and the third elastic plate 17 are both V-shaped structures, the connecting plate 19 is a V-shaped structure, the bending part of the V-shaped structure of the connecting plate 9 is an arc-shaped structure, the thickness of the connecting plate 19 is smaller than the thickness of the second abutment plate 18, the first elastic plate 14, the second elastic plate 16 and the third elastic plate 17 are all fixedly connected to the inner wall of the fixing groove 5, a pair of second elastic plates 16 and a pair of third elastic plates 17 are symmetrically arranged on both sides of the connecting plate 19, the second elastic plate 16 is located on the side away from the connecting plate 19, and the third elastic plate 17 is located on the side close to the connecting plate 19.

[0051] When the second fixed rod 2, the supplementary component and the adjustment sleeve 7 are installed, the supplementary component is installed in the fixed groove 5 of the second fixed rod 2, the adjustment sleeve 7 is sleeved on the second fixed rod 2, and the annular portion 72 of the adjustment sleeve 7 is sleeved on the fixed groove 5 and the supplementary component, so that the inner wall of the annular portion 72 of the adjustment sleeve 7 presses the supplementary component.

[0052] Specifically, the supplementary component is arranged on the inner wall of the fixing groove 5 opened on the second fixing rod 2, the annular portion 72 of the adjusting sleeve 7 is sleeved on the fixing groove of the second fixing rod 2 and the supplementary component, the first elastic plate 14, the second elastic plate 16 and the third elastic plate 17 are all elastic V-shaped structures, and the first elastic plate 14, the second elastic plate 16 and the third elastic plate 17 are all in a compressed state, so that the entire supplementary component is arranged in the adjusting sleeve 7.

[0053] The variable stiffness fixation rod for spinal surgery of the present invention is used, and the vertebral arch steel screw 26, the second fixation rod 2, the supplementary component and the adjustment sleeve 7 are combined to form an auxiliary fixation segment 28, and the first fixation rod 1 forms a main fixation segment 29. When the fixation rod is used, a vertebral arch steel screw 2 is installed near the end of the auxiliary fixation segment 28, a vertebral arch steel screw 26 is installed at the connection between the auxiliary fixation segment 28 and the main fixation segment 29, and a vertebral arch steel screw 26 is installed near the end of the main fixation segment 29. Specifically, a vertebral arch steel screw 26 is installed at the installation protrusion 3 on the second fixation rod 2, and a vertebral arch steel screw 26 is installed near the end of the first fixation rod 1. When a vertebral arch steel screw 26 is installed near the end of the auxiliary fixing segment 28, the auxiliary fixing segment 28 is installed in the steel screw installation groove 261 of the vertebral arch steel screw 26, the positioning groove 8 on the adjustment sleeve 7 is aligned with the end of the steel screw installation groove 261, and the auxiliary fixing segment 28 is locked in the steel screw installation groove 261 by using the locking screw plug 27, so that the vertebral arch steel screw 26 locks the auxiliary fixing segment 28, and the adjustment sleeve 7 plays the role of alignment and installation. When the fixing segment 29 is installed with the vertebral arch steel screw 26, the fixing segment 29 is installed in the steel screw installation groove 261 of the vertebral arch steel screw 26, and the fixing segment 29 is locked in the steel screw installation groove 261 by using the locking screw plug 27, so that the vertebral arch steel screw 26 locks the auxiliary fixing segment 29.

[0054] Specifically, when the auxiliary fixation segment 28 is installed on the pedicle screw 26, the position of the supplementary component is respectively aligned with the pedicle screw 26 and the locking screw plug 27. More specifically, the position of the first abutment plate 15 is aligned with the pedicle screw 26, and at this time, the position of the second abutment plate 18 is aligned with the locking screw plug 27. During the postoperative recovery process, after the adjustment sleeve 7 is absorbed by the patient's body, the adjustment sleeve 7 can no longer exert pressure on the first elastic plate 14, the second elastic plate 16 and the third elastic plate 17, exposing part of the structure and supplementary components of the second fixing rod 2. At this time, a certain gap is formed between the second fixing rod 2 and the locking screw 27, and between the second fixing rod 2 and the inner wall of the vertebral arch steel screw 26. Under the action of the elastic force of the first elastic plate 14, the first abutment plate 15 abuts against the bottom of the inner wall of the vertebral arch steel screw 26 to achieve compensation between the bottom of the second fixing rod 2 and the bottom of the inner wall of the vertebral arch steel screw 26. Under the elastic force of the second elastic plate 16 and the third elastic plate 17, the second abutment plate 18 can be driven to bend so that a pair of second abutment plates The relatively close end of 18 is pressed against the bottom of the locking screw plug 27 under the action of the elastic force of the third elastic plate 17. At this time, the connecting plate 19 is stretched. The thickness of the connecting plate 19 is less than that of the second abutting plate 18, which is convenient for stretching when the second abutting plate 18 is bent and improves the stability of the connection between the pair of second abutting plates 18. The relatively far ends of the pair of second abutting plates 18 are pressed against the outer wall of the locking screw plug 27 under the action of the elastic force of the second elastic plate 16. The second abutting plate 18 cooperates with the first abutting plate 15. When the adjustment sleeve 7 is absorbed, the patient's spinal joint mobility is improved, and the second fixing rod 2 will not move during the activity to cause failure of the internal fixation system, thereby further improving the stability of the internal fixation system.

[0055] Specifically, Figures 6 to 8 When a vertebral arch steel screw 26 is installed near the end of the auxiliary fixing segment 28, the supplementary component of the auxiliary fixing segment 28 is installed in the steel screw installation groove 261 of the vertebral arch steel screw 26, the positioning groove 8 on the adjustment sleeve 7 is aligned with the end of the steel screw installation groove 261, and then a locking screw plug 27 is used to lock the auxiliary fixing segment 28 in the steel screw installation groove 261, the bottom 272 of the locking screw plug abuts against the two first limiting plates 20, the two second limiting plates 30 and the two third arc plates 25, and the threaded surface 271 of the locking screw plug 27 abuts between the two first arc plates 23 and between the two second arc plates 24. At the same time, the two second arc plates 24 clamp the threaded surface 271 of the locking screw plug 27. Figure 8 As shown, Figure 8 The middle locking screw plug 27 is arranged above the supplementary component. Figure 8 It is only used to show the position of the locking screw plug 27. Figure 8The locking screw plug 27 in the supplementary component does not achieve abutment with the supplementary component. Through the first curved plate 23, the second curved plate 24 and the third curved plate 25, the second abutting plate 18 includes a first limiting plate 20 and a second limiting plate 30 connected to each other, and a weakening groove 22 is provided at the connection between the first limiting plate 20 and the second limiting plate 30. When the second elastic plate 16 and the third elastic plate 17 restore their elasticity, the weakening groove 22 is provided to facilitate the deformation of the second abutting plate 18. When the first limiting plate 20 is pressed against the bottom 272 of the locking screw plug under the action of the elastic force of the second elastic plate 16, the first curved plate 23 provided at one end of the first limiting plate 20 abuts against the threaded surface 271 of the locking screw plug 27. The arcs of the first curved plate 23 and the second curved plate 24 are in opposite directions, so that the second curved plate 23 and the second curved plate 24 are in opposite directions. The plate 24 is clamped with the threaded surface 271 of the locking screw plug 27. The first arc plate 23 has an arc-shaped structure and the arc protrudes toward the outer wall of the second abutment plate 18, and has a clamping tendency with the threaded surface 271 of the locking screw plug 27, thereby improving the abutment effect with the threaded surface 271 of the locking screw plug 27. The second limiting plate 30 drives the third arc plate 25 provided at one end of the third elastic plate 17 to abut against the bottom 272 of the locking screw plug under the elastic force of the third elastic plate 17. The third arc plate 25 has an arc-shaped structure and abuts against the bottom 272 of the locking screw plug more stably. When the second fixing rod 2 moves, the third arc plate 25 is always abutted against the bottom 272 of the locking screw plug, thereby further improving the stability of the second fixing rod 2 when in use.

[0056] In summary, the second abutment plate 18 and the first abutment plate 15 are respectively matched with the second elastic plate 16, the third elastic plate 17 and the first elastic plate 14, and matched with the adjustment sleeve 7 arranged in the stiffness adjustment assembly. When the adjustment sleeve 7 is absorbed by the patient's body, under the action of the elastic force of the second elastic plate 16, the third elastic plate 17 and the first elastic plate 14, the second abutment plate 18 and the first abutment plate 15 are respectively pressed against the bottom 272 and the threaded surface 271 of the locking screw plug and the bottom of the inner wall of the pedicle screw 26, ensuring that the second fixing rod 2 will not move during the activity, causing failure of the internal fixation system, thereby further improving the stability of the internal fixation system.

[0057] The working process of the technical solution provided by the present invention is as follows:

[0058] When performing spinal fixation surgery on a patient, the cone steel screw is first driven into a suitable position of the patient's spine, and the variable stiffness fixing rod designed by the present invention is clamped into the steel screw installation groove 261 of the vertebral arch steel screw 26, and the locking screw plug 27 is used to fix the main fixing segment 29 and the vertebral arch steel screw 26, and the auxiliary fixing segment 28 and the vertebral arch steel screw 26 respectively. The adjustment sleeve 7, the fixing block 9 and the connecting block 10 are all made of medical magnesium alloy and can be absorbed by the patient's body. During the postoperative and recovery process of the patient, the adjustment sleeve 7, the fixing block 9 and the connecting block 10 have not been absorbed by the patient's body just after the operation. At this time, the stiffness of the entire fixing rod is the highest. During the recovery process, the adjustment sleeve 7, the fixing block 9 and the connecting block 10 will gradually be absorbed by the patient's body, so that the second fixing rod 2 of the auxiliary fixing segment 28 is completely exposed, and the matching groove 6 provided on the second fixing rod 2 is aligned with the patient's spinal surface. The side of the second fixing rod 2 provided with the matching groove 6 is in contact with the patient's spinal surface, thereby improving the joint activity of the spinal auxiliary fixing segment 28.

[0059] During the postoperative recovery process, after the adjustment sleeve 7 is absorbed by the patient's body, the adjustment sleeve 7 can no longer continue to exert pressure on the first elastic plate 14, the second elastic plate 16 and the third elastic plate 17, exposing the second fixing rod 2 and the supplementary assembly. At this time, there is a certain gap between the contact positions of the top of the second fixing rod 2 and the bottom 272 of the locking screw plug, and the bottom of the second fixing rod 2 and the inner wall of the steel nail installation groove 261 of the vertebral arch steel nail 26. Under the action of the elastic force of the first elastic plate 14, the first abutment plate 15 abuts against the bottom of the inner wall of the steel nail installation groove 261 of the vertebral arch steel nail 26 to achieve compensation between the bottom of the second fixing rod 2 and the bottom of the inner wall of the vertebral arch steel nail 26. Under the elastic force of the second elastic plate 16 and the third elastic plate 17, the second abutment plate 18 can be driven to bend so that the relatively close ends of a pair of second abutment plates 18 are tightly pressed against the bottom of the locking screw plug 27 under the action of the elastic force of the third elastic plate 17.

[0060] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the above preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A variable stiffness fixation rod for spinal surgery, characterized in that: include: A first fixing rod, one end of the second fixing rod is connected to the first fixing rod, two fixing grooves arranged opposite to each other are provided on the outer wall of the other end of the second fixing rod, a protruding mounting portion is provided on the outer side of the circumference of the second fixing rod, mounting protrusions are provided at both ends of the mounting portion, two groups of limiting grooves are formed on the outer side of the mounting portion, and a matching groove is provided on the mounting portion; A stiffness adjustment component, wherein the stiffness adjustment component is sleeved on the second fixing rod and the stiffness adjustment component adjusts the stiffness of the second fixing rod during use; A supplementary component, the supplementary component is installed in the fixing groove of the second fixing rod, and the supplementary component is pressed against the stiffness adjustment component. After the stiffness adjustment component is dissolved, the supplementary component supplements the gap between the stiffness adjustment component and the pedicle screw, and the gap between the stiffness adjustment component and the locking screw plug, and the supplementary component is connected to the second fixing rod; The stiffness adjustment assembly includes an adjustment sleeve, the adjustment sleeve includes a circular ring portion and a fixed portion, a positioning groove is provided on the circular ring portion near the end of the fixed portion, two groups of fixing blocks are provided on the fixed portion, the shapes of the two groups of fixing blocks are adapted to the shapes of the two groups of limiting grooves on the mounting portion, and the adjustment sleeve and the fixing blocks are both made of medical magnesium alloy; The supplementary component comprises a pair of first elastic plates fixedly connected to the bottom of a fixing groove of one second fixing rod, the outer walls of the pair of first elastic plates are fixedly connected to the same first abutting plate, a pair of second elastic plates and a pair of third elastic plates are fixedly connected in the fixing groove of another second fixing rod, the top of each second elastic plate and each third elastic plate is fixedly connected to the same second abutting plate, the opposite sides of a pair of second abutting plates are fixedly connected to the same connecting plate, the pair of second elastic plates and the pair of third elastic plates are symmetrically arranged on both sides of the connecting plate, the second elastic plate is located on the side away from the connecting plate, the third elastic plate is located on the side close to the connecting plate, and the first elastic plate is in a V-shaped structure; The stiffness adjustment component also includes a connecting block, which is installed in the matching groove and is made of medical magnesium alloy.

2. The variable stiffness fixation rod for spinal surgery according to claim 1, characterized in that: The mounting protrusion is in a semicircular structure, and a transition plate is fixedly connected to a connection point between the mounting protrusion and the first fixing rod.

3. The variable stiffness fixation rod for spinal surgery according to claim 1, characterized in that: The arrangement density of the limiting grooves increases from low to high from the two ends of the mounting portion to the middle position, and the size of the limiting grooves decreases from high to low from the two ends of the mounting portion to the middle position.

4. The variable stiffness fixation rod for spinal surgery according to claim 1, characterized in that: The matching groove includes a plurality of arc grooves, two adjacent arc grooves are connected by a rectangular groove, and the sizes of the plurality of arc grooves are arranged from small to large from the two ends of the installation to the middle position.

5. The variable stiffness fixation rod for spinal surgery according to claim 1, characterized in that: The second elastic plate and the third elastic plate are both in a V-shaped structure, the connecting plate is in a V-shaped structure, the bending part of the V-shaped structure is in an arc-shaped structure, and the thickness of the connecting plate is smaller than the thickness of the second abutting plate.

6. The variable stiffness fixation rod for spinal surgery according to claim 1, characterized in that: The second abutment plate includes a first limit plate and a second limit plate connected to each other, a weakening groove is provided at the connection between the first limit plate and the second limit plate, one end of the first limit plate is fixedly connected to the first arc plate and the second arc plate connected to each other, and one end of the second limit plate is fixedly connected to the third arc plate.

7. The variable stiffness fixation rod for spinal surgery according to claim 6, characterized in that: The arc directions of the first arc plate and the second arc plate are opposite, and the arc directions of the first arc plate and the third arc plate are the same, and both are convex in a direction away from the outer wall of the second abutting plate.

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