Growth rod and orthopedic fixation system

Abstract

The invention relates to a growth rod and an orthopedic fixing system.The growth rod comprises a first rod, a second rod and a one-way valve, a containing cavity is formed in the first end of the first rod, the containing cavity is provided with a first cavity and a second cavity, a sliding base is arranged at the first end of the second rod, and the sliding base is arranged in the containing cavity in a sliding mode in the axial direction of the first rod; the first cavity and the second cavity are formed in the two axial sides of the sliding base respectively, the second cavity is closer to the second end of the first rod than the first cavity, and the one-way valve is arranged on the sliding base. The one-way valve can allow a medium in the first cavity to flow towards the interior of the second cavity. The growth rod can correspondingly extend along with the growth of the spine of a patient, the risk of complications and the like caused by repeated open operations can be reduced, and the spine orthopedic effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a growth rod and an orthopedic fixation system. Background Art

[0002] Growing rod technology is used for non-fusion correction surgery for early-onset scoliosis in children or idiopathic scoliosis in adolescents. It is generally used for growing and developing minors. It maintains the balance of the coronal and sagittal planes of the spine while retaining the growth potential of the spine, allowing the thorax to continue to grow, and improving the thoracic volume and cardiopulmonary function. In related technologies, growing rods usually require repeated open surgeries to ensure the normal growth of the spine, that is, patients need to undergo a growing rod lengthening surgery at regular intervals, but the above surgical plan greatly increases the risk of complications. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention provides a growth rod that can be extended accordingly with the growth of the patient's spine, which is beneficial for reducing the risks of complications caused by repeated open surgeries and has a better spinal correction effect.

[0005] The embodiment of the present invention further provides an orthopedic fixation system.

[0006] The growing rod of an embodiment of the present invention comprises: a first rod, a first end of which is provided with a accommodating cavity, the accommodating cavity having a first chamber and a second chamber; a second rod, a first end of which is provided with a sliding seat, the sliding seat is arranged in the accommodating cavity along the axial direction of the first rod, the first chamber and the second chamber are respectively arranged on both sides of the axial direction of the sliding seat, and the second chamber is closer to the second end of the first rod than the first chamber; a one-way valve, the one-way valve is provided on the sliding seat, and when one of the first rod and the second rod is subjected to a traction force away from the other that is greater than a preset traction force, the one-way valve can allow the medium in the first chamber to flow toward the second chamber.

[0007] According to the growing rod of the embodiment of the present invention, when the growing rod is implanted on the spine of the patient and accompanies the growth of the spine or is pulled externally, one of the first rod and the second rod will be subjected to a traction force away from the other, and when the traction force is greater than a preset traction force, the one-way valve can allow the medium in the first chamber to flow toward the second chamber, so that the space of the second chamber increases and the space of the first chamber decreases synchronously, thereby making the first rod and the second rod move away from each other, so that the growing rod can be synchronously extended as the spine grows. Since the one-way valve has the characteristic of one-way conduction, the medium in the second chamber will not flow back into the first chamber, thereby improving the stability of the support after the growth rod is extended.

[0008] Therefore, the growth rod of the embodiment of the present invention can be stretched accordingly with the growth of the patient's spine, which is beneficial to reduce the risk of complications caused by repeated open surgery, and the spinal correction effect is better.

[0009] In some embodiments, a first channel is provided in the sliding seat, and both ends of the first channel are respectively connected to the first chamber and the second chamber, and the one-way valve includes an elastic member and a valve core, and the valve core is provided in the first channel and connected to the elastic member, and the elastic member has an elastic force for driving the valve core to close the first channel, and the elastic force is equal to the preset traction force. When the traction force is greater than the preset traction force, the valve core makes the first channel conductive.

[0010] In some embodiments, the first port of the first channel is communicated with the first chamber, the second port of the first channel is communicated with the second chamber, the valve core has a first sealing surface, when the traction force is greater than the preset traction force, the first sealing surface is spaced apart from the first port, when the traction force is less than or equal to the preset traction force, the first sealing surface abuts against the first port.

[0011] In some embodiments, the first sealing surface is a conical surface, and the conical surface is gradually tapered in the direction from the second port to the first port; and / or the valve core includes a core body and a first sealing ring, the first sealing ring is sleeved on the core body, and the first sealing surface is molded on the first sealing ring.

[0012] In some embodiments, the one-way valve further includes a limit member, which is disposed in the first channel and arranged adjacent to the second port, one end of the elastic member is connected to the valve core, and the other end of the elastic member is connected to the limit member.

[0013] In some embodiments, the outer wall surface of the limit member is threadedly matched with the inner wall surface of the first channel; and / or, the limit member is provided with a mounting groove at one end adjacent to the valve core, and the other end of the elastic member abuts against the mounting groove.

[0014] In some embodiments, a first hole and a second hole are provided in the second rod, the first hole extends radially along the second rod, the second hole extends axially along the second rod, the radial outer end of the first hole is connected to the first chamber, the radial inner end of the first hole is connected to the second hole, and the second hole is connected to the first channel.

[0015] In some embodiments, the one-way valve also includes a second sealing ring, which is sleeved on the outer peripheral wall of the sliding seat, and the outer peripheral wall of the second sealing ring abuts against the inner peripheral wall of the accommodating cavity; and / or, the first chamber and the second chamber are both filled with a medium; and / or, in a cross-section orthogonal to the first rod, the cross-sectional profiles of the accommodating cavity and the sliding seat are both polygonal, and the sliding seat is non-rotatably matched with the accommodating cavity.

[0016] In some embodiments, the first rod includes a first rod body, a fixing seat and a sealing cover, the fixing seat is arranged at the end of the first rod body, the sealing cover is detachably mounted on an end of the fixing seat away from the first rod body, and the sealing cover and the fixing seat together form the accommodating cavity; and / or, the first rod includes a fixing seat and a sealing cover, the sealing cover and the fixing seat together form the accommodating cavity, the growing rod also includes a third sealing ring, the third sealing ring is arranged in the accommodating cavity, the third sealing ring is clamped between the sealing cover and the fixing seat, and the third sealing ring is against the inner circumferential wall of the second rod.

[0017] An orthopedic fixation system according to another embodiment of the present invention comprises: a growing rod, which is any one of the growing rods described in the embodiments of the present invention; and at least two pedicle screws, wherein at least one of the pedicle screws is connected to each of the first rod and the second rod.

[0018] According to the orthopedic fixation system of an embodiment of the present invention, when the growth rod is implanted on the patient's spine and accompanies the growth of the spine or is pulled externally, one of the first rod and the second rod will be subjected to a traction force away from the other, and when the traction force is greater than a preset traction force, the one-way valve can allow the medium in the first chamber to flow toward the second chamber, so that the space of the second chamber increases and the space of the first chamber decreases synchronously, thereby allowing the first rod and the second rod to move away from each other, so that the growth rod can be synchronously extended as the spine grows. Since the one-way valve has a one-way conduction characteristic, the medium in the second chamber will not flow back into the first chamber, thereby improving the stability of the support after the growth rod is extended.

[0019] Therefore, the orthopedic fixation system of the embodiment of the present invention can be stretched accordingly with the growth of the patient's spine, which is beneficial to reduce the risks of complications caused by repeated open surgeries, and the spinal correction effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of a growing rod extending according to an embodiment of the present invention.

[0021] Figure 2 is a partial cross-sectional view of a growing rod (unstretched) according to an embodiment of the present invention.

[0022] Figure 3 is a partial cross-sectional view of a growing rod (during the extension process) according to an embodiment of the present invention.

[0023] Figure 4 It is a partial cross-sectional view of the growing rod and the installation tool according to the embodiment of the present invention when they are matched.

[0024] Figure 5 FIG. 4 is a partial cross-sectional view of a second rod of a growing rod according to an embodiment of the present invention.

[0025] Figure 6 FIG. 4 is a partial cross-sectional view of a first rod of a growing rod according to an embodiment of the present invention.

[0026] Figure 7 4 is a cross-sectional view of a valve core of a growing rod according to an embodiment of the present invention.

[0027] Figure 8 It is a partial installation cross-sectional view of the sealing cover and the third sealing ring of the growing rod according to the embodiment of the present invention.

[0028] Fig. 9 4 is a cross-sectional view of a stopper of a growing rod according to an embodiment of the present invention.

[0029] Reference numerals: 1. first rod; 11. accommodating chamber; 111. first chamber; 112. second chamber; 12. first rod body; 13. fixing seat; 14. sealing cover; 15. third sealing ring; 2. second rod; 21. sliding seat; 211. first channel; 2111. first port; 2112. second port; 212. second slot; 22. second rod body; 221. first hole; 222. second hole; 23. second sealing ring; 3. One-way valve; 31. Elastic member; 32. Valve core; 321. Core body; 3211. First clamping groove; 322. First sealing ring; 3221. First sealing surface; 33. Limiting member; 331. Through hole; 332. Mounting groove; 4. Pedicle screws; 51. Airbag head; 52. Hose; 53. Air source. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0031] Please refer to the following Figures 1 to 9 A growing rod and an orthopedic fixation system according to embodiments of the present invention are described.

[0032] like Figures 1 to 4 As shown, the growing rod of the embodiment of the present invention comprises: a first rod 1, a second rod 2 and a one-way valve 3. A receiving chamber 11 is provided at the first end of the first rod 1, and the receiving chamber 11 has a first chamber 111 and a second chamber 112. A sliding seat 21 is provided at the first end of the second rod 2. The sliding seat 21 is arranged in the receiving chamber 11 along the axial direction of the first rod 1, and the first chamber 111 and the second chamber 112 are arranged on both sides of the axial direction of the sliding seat 21, respectively. The second chamber 112 is closer to the second end of the first rod 1 than the first chamber 111. The one-way valve 3 is arranged on the sliding seat 21. When one of the first rod 1 and the second rod 2 is subjected to a traction force greater than a preset traction force away from the other, the one-way valve 3 can allow the medium in the first chamber 111 to flow toward the second chamber 112.

[0033] It should be noted that the traction force can come from the normal growth of the patient's spine or from external traction on the patient.

[0034] Among them, the one-way valve 3 can allow the medium in the first chamber 111 to flow toward the second chamber 112 only when the traction force reaches the set threshold (that is, the traction force is greater than the preset traction force). In other words, when the traction force is greater than the set threshold, the one-way valve 3 is opened, and when the traction force is less than or equal to the set threshold (that is, the traction force is less than or equal to the preset traction force), the one-way valve 3 is in a closed state. The set threshold can be selected according to the traction force generated by the normal growth of the human spine, and the present invention does not limit this.

[0035] For example, the first rod 1 is connected to the vertebral body at the lower side of the one-way valve, and the second rod 2 is connected to the vertebral body at the upper side of the one-way valve. For another example, the first rod 1 is connected to the vertebral body at the upper side of the one-way valve, and the second rod 2 is connected to the vertebral body at the lower side of the one-way valve.

[0036] It is understandable that the first rod 1 and the second rod 2 are respectively connected to the vertebral bodies on different upper and lower sides of the one-way valve. Therefore, when the spine grows normally or is pulled externally, the first rod 1 and the second rod 2 can move away from each other to stretch synchronously with the spine.

[0037] According to the growing rod of the embodiment of the present invention, when the growing rod is implanted on the patient's spine and accompanies the growth of the spine or is pulled externally, one of the first rod 1 and the second rod 2 will be subjected to a traction force away from the other, and when the traction force is greater than the preset traction force, the one-way valve 3 can allow the medium in the first chamber 111 to flow toward the second chamber 112, so that the space of the second chamber 112 increases and the space of the first chamber 111 decreases synchronously, thereby allowing the first rod 1 and the second rod 2 to move away from each other, so that the growing rod can be synchronously extended with the growth of the spine. Since the one-way valve 3 has the characteristic of unidirectional conduction, the medium in the second chamber 112 will not flow back into the first chamber 111, thereby improving the stability of the support after the growth rod is extended.

[0038] It can be understood that the sliding seat 21 can act as a "sliding piston" in the accommodating chamber 11. When the first rod 1 and the second rod 2 move away from each other under the traction force of the spine, the pressure in the first chamber 111 will increase, and the pressure in the second chamber 112 will decrease. At this time, the one-way valve 3 can be opened under the pressure difference, that is, the one-way valve 3 can allow the medium in the first chamber 111 to flow toward the second chamber 112 to balance the pressure difference between the first chamber 111 and the second chamber 112.

[0039] When the growth rod is extended a certain distance, the traction force on the first rod 1 and the second rod 2 will decrease until it is less than the preset traction force. At this time, the pressure difference between the first chamber 111 and the second chamber 112 is roughly balanced, and the one-way valve 3 is closed, thereby limiting the exchange of media in the first chamber 111 and the second chamber 112 to avoid the problem of retraction of the growth rod.

[0040] The growing rod of the embodiment of the present invention can be stretched accordingly with the growth of the patient's spine, and the supporting force of the growing rod after stretching can be guaranteed, thereby achieving the purpose of opening and correction, and retaining the growth ability of the spine and thorax, reducing the number of open surgeries. After a single operation of opening and correction using the growing rod of the embodiment of the present invention, the growing rod can be extended "grown" infinitely within the maximum extension range, reducing the number of open surgeries, avoiding complications such as infection, soft tissue defects, and spontaneous fusion of the spine, and achieving a good correction effect.

[0041] Alternatively, if Figure 2 and Figure 5 As shown, a first channel 211 is provided in the sliding seat 21, and both ends of the first channel 211 are respectively connected to the first chamber 111 and the second chamber 112. The one-way valve 3 includes an elastic member 31 and a valve core 32. The valve core 32 is provided in the first channel 211 and connected to the elastic member 31. The elastic member 31 has an elastic force for driving the valve core 32 to close the first channel 211, and the elastic force is equal to the preset traction force.

[0042] When the traction force is greater than the preset traction force (elastic force), the valve core 32 opens the first channel 211. Correspondingly, when the traction force is less than or equal to the preset traction force (elastic force), the valve core 32 can close the first channel 211 under the action of the elastic force, thereby realizing the opening and closing of the one-way valve 3.

[0043] It is understandable that if Figure 3 As shown, when the traction force is greater than the preset traction force (elastic force), the sliding seat 21 moves upward, and the pressure of the first chamber 111 is greater than the pressure of the second chamber 112, so that the one-way valve 3 is opened, and the first chamber 111 is connected to the second chamber 112 through the first channel 211. Figure 2 As shown, when the pressure of the first chamber 111 is substantially equal to the pressure of the second chamber 112, that is, the pressure difference decreases or disappears, the traction force is less than or equal to the preset traction force (elastic force), and the valve core 32 can close the first channel 211 under the action of the elastic force.

[0044] The growth rod of the embodiment of the present invention is designed with the one-way valve 3 as the above structure, so that the extension of the growth rod can only be carried out when the traction force is greater than the elastic force. Therefore, the problem of the growth rod also extending synchronously when the patient's spine is bent or pulled in daily life can be avoided, which is conducive to improving the reliability of the growth rod after implantation. In addition, the one-way valve 3 is designed with the structure of "elastic member 31 + valve core 32", which can reduce the number of parts required for the one-way valve 3, and the structural design is simple and reliable.

[0045] like Figure 3 and Figure 5As shown, the first port 2111 of the first channel 211 is in communication with the first chamber 111, the second port 2112 of the first channel 211 is in communication with the second chamber 112, the valve core 32 has a first sealing surface 3221, when the traction force is greater than the preset traction force (elastic force), the first sealing surface 3221 is spaced apart from the first port 2111, when the traction force is less than or equal to the preset traction force (elastic force), the first sealing surface 3221 is in contact with the first port 2111. Figure 2 and Figure 3 As shown, the first port 2111 is arranged adjacent to the first chamber 111, and the second port 2112 is arranged adjacent to the second chamber 112. The valve core 32 can move under the interaction of the pressure difference force of the accommodating chamber 11 and the elastic force of the elastic member 31 to close and open the first port 2111. When the traction force is less than or equal to the elastic force, the elastic member 31 can press the valve core 32 upward so that the first sealing surface 3221 contacts the first port 2111, thereby improving the sealing effect when the one-way valve 3 is closed, so that the support of the growth rod is more stable.

[0046] Alternatively, if Figure 3 and Figure 7 As shown, the first sealing surface 3221 is a conical surface, and the conical surface is gradually narrowed in the direction from the second port 2112 to the first port 2111. When the traction force is less than or equal to the elastic force, the cone structure on the upper side of the valve core 32 can block the first port 2111. When the traction force is greater than the elastic force, the cone structure on the upper side of the valve core 32 can be spaced apart from the first port 2111 to form a gap for medium circulation.

[0047] The growth rod of the embodiment of the present invention adopts the above-mentioned structural design for the first sealing surface 3221 (conical surface), which can, on the one hand, axially limit the position of the valve core 32 to prevent the valve core 32 from upwardly slipping out of the first port 2111 under the action of the elastic member 31; on the other hand, the sealing structure in the form of a conical surface can increase the contact area between the valve core 32 and the first port 2111 to ensure the sealing effect. In addition, the inclined flow channel gap formed when the valve core 32 is spaced apart from the first port 2111 can allow the medium to be introduced into the first channel 211 more smoothly.

[0048] like Figure 7 As shown, in order to further improve the sealing effect between the valve core 32 and the first port 2111, the valve core 32 includes a core body 321 and a first sealing ring 322, the first sealing ring 322 is sleeved on the core body 321, and the first sealing surface 3221 is formed on the first sealing ring 322. It can be understood that the core body 321 and the first sealing ring 322 are made of different materials. The first sealing ring 322 can be made of medical grade silicone rubber, thereby ensuring the sealing effect between the valve core 32 and the first port 2111 and improving the safety of the growth rod after implantation into the human body.

[0049] In one example, the first sealing ring 322 and the core body 321 are snap-fitted. Figure 7 As shown, a first card groove 3211 is provided on the core body 321, and the first card groove 3211 is arranged around the outer peripheral wall of the core body 321. The first sealing ring 322 is sleeved and clamped on the core body 321, thereby ensuring the firmness of the connection between the first sealing ring 322 and the core body 321 and facilitating assembly.

[0050] Alternatively, if Figures 2 to 4 and Fig. 9 As shown, the one-way valve 3 also includes a limit member 33, which is arranged in the first channel 211 and adjacent to the second port 2112. One end of the elastic member 31 is connected to the valve core 32, and the other end of the elastic member 31 is connected to the limit member 33. The growth rod of the embodiment of the present invention can limit the installation of the elastic member 31 by setting the limit member 33, so as to facilitate the assembly of the one-way valve 3.

[0051] like Figure 2 , Figure 3 and Fig. 9 As shown, a through hole 331 is provided in the stopper 33, and the through hole 331 penetrates the stopper 33 along the axial direction of the sliding seat 21. Thus, the through hole 331 in the stopper 33 can make the pressure difference between the first channel 211 and the second chamber 112 equal, and will not interfere with the flow of the medium from the first channel 211 to the second chamber 112.

[0052] In one example, the outer wall surface of the stopper 33 is threadedly engaged with the inner wall surface of the first channel 211. Fig. 9 As shown, the limiter 33 is a hollow screw plug structure, and the limiter 33 can be screwed into the first channel 211 from bottom to top, thereby facilitating the assembly of the one-way valve 3, and the structure design is simple and the stability is good.

[0053] like Figure 2 , Figure 7 and Fig. 9 As shown, a mounting groove 332 is provided at one end of the limiter 33 adjacent to the valve core 32, and the other end of the elastic member 31 abuts against the mounting groove 332. It can be understood that the mounting groove 332 can limit the lower end of the elastic member 31 radially and axially, and the valve core 32 can limit the upper end of the elastic member 31 axially and radially. When the elastic member 31 is compressed, the deformation of the elastic member 31 can be made more stable, the speed balance when the growth rod is extended is improved, and the adjustment effect is better.

[0054] Exemplarily, the elastic member 31 may be a cylindrical helical spring, a disc spring or a leaf spring. In the example of the present application, the elastic member 31 is a cylindrical helical spring, which is a hollow helical structure. In addition, compared with the solution of "disc spring or leaf spring", the cylindrical helical spring is more stable when deformed by force, which can make the growth rod stretch at a balanced speed and have a better adjustment effect.

[0055] Alternatively, if Figure 2 and Figure 5 As shown, a first hole 221 and a second hole 222 are provided in the second rod 2, the first hole 221 extends in the radial direction of the second rod 2, the second hole 222 extends in the axial direction of the second rod 2, the radial outer end of the first hole 221 is connected to the first chamber 111, the radial inner end of the first hole 221 is connected to the second hole 222, and the second hole 222 is connected to the first channel 211. The growing rod of the embodiment of the present invention can introduce the medium in the first chamber 111 into the second hole 222 in the horizontal direction through the first hole 221 by providing the first hole 221 and the second hole 222. Since the second hole 222 extends in the axial direction, the force applied by the medium when vertically squeezing the valve core 32 can be made more uniform, thereby reducing the problem of tilting and deflection of the valve core 32 when the first hole 221 is directly connected to the valve core 32, and improving the uniformity of the force applied to the valve core 32.

[0056] In one example, there are multiple first holes 221, and the multiple first holes 221 are arranged at intervals along the circumference of the second rod 2, that is, the multiple first holes 221 can simultaneously flow the medium, thereby improving the efficiency of pressure difference regulation between the first chamber 111 and the second chamber 112, and making the valve core 32 evenly stressed vertically, thereby improving the length adjustment effect of the growth rod.

[0057] like Figure 5 As shown, the second rod 2 includes a second rod body 22 and a sliding seat 21, the sliding seat 21 is arranged at the first end of the second rod body 22, and the first hole 221 and the second hole 222 are arranged between the second rod body 22 and the sliding seat 21. The second hole 222 is coaxially arranged with the first channel 211, and the inner diameter of the second hole 222 is substantially the same as the inner diameter of the first port 2111. There are a plurality of first holes 221, and the plurality of first holes 221 are radially arranged, and the radial inner ends of the plurality of first holes 221 are all connected with the second holes 222.

[0058] Alternatively, if Figure 2 and Figure 5As shown, the one-way valve 3 further includes a second sealing ring 23, which is sleeved on the outer peripheral wall of the sliding seat 21, and the outer peripheral wall of the second sealing ring 23 abuts against the inner peripheral wall of the accommodating chamber 11. It can be understood that the sliding seat 21 and the accommodating chamber 11 are sealed and connected through the second sealing ring 23, thereby preventing the medium from flowing through the gap between the sliding seat 21 and the accommodating chamber 11, improving the sealing effect of the accommodating chamber 11, and making the supporting effect of the growth rod better.

[0059] like Figure 5 As shown, the outer wall of the sliding seat 21 is provided with a second groove 212, and the second sealing ring 23 is sleeved and clamped in the second groove 212. The outer wall of the second sealing ring 23 and the outer wall of the sliding seat 21 are both in contact with the inner wall of the accommodating chamber 11, thereby further improving the sealing effect between the sliding seat 21 and the inner wall of the accommodating chamber 11.

[0060] For example, Figure 5 As shown, there are multiple second sealing rings 23, and the multiple second sealing rings 23 are arranged at intervals along the axial direction of the sliding seat 21. Figure 5 As shown, there are two second slots 212 , which are spaced apart along the axial direction of the sliding seat 21 , and there are two second sealing rings 23 , which are installed in the two second slots 212 in a one-to-one correspondence.

[0061] Optionally, the first chamber 111 and the second chamber 112 are both filled with a medium. The medium may be a lubricating liquid, and the lubricating liquid may be medical-grade liquid silicone oil, paraffin oil, glycerin or other safer lubricating liquids. Since the medium is a lubricating liquid, the volume of the lubricating liquid remains substantially unchanged under pressure, which makes the sealing of the lubricating liquid relatively easy to control, thereby facilitating the reduction of the probability of leakage of the medium in the growth rod, and the lubricating liquid can lubricate the movement of the sliding seat 21, thereby avoiding the problem of the sliding seat 21 getting stuck in the accommodating chamber 11.

[0062] Optionally, in a cross section orthogonal to the first rod 1, the cross-sectional profiles of the accommodating cavity 11 and the sliding seat 21 are both polygonal, and the sliding seat 21 is non-rotatably matched with the accommodating cavity 11. This can limit the relative rotation of the first rod 1 and the second rod 2, and improve the stability of the growing rod after implantation.

[0063] For example, the cross-sectional profiles of the accommodating cavity 11 and the sliding seat 21 are both regular hexagons.

[0064] Alternatively, if Figure 2 and Figure 3As shown, the first rod 1 includes a first rod body 12, a fixing seat 13 and a sealing cover 14. The fixing seat 13 is arranged at the end of the first rod body 12. The sealing cover 14 is detachably mounted on the end of the fixing seat 13 away from the first rod body 12. The sealing cover 14 and the fixing seat 13 enclose a receiving cavity 11. Since the sealing cover 14 is detachably connected to the fixing seat 13, before assembling the growing rod, the sealing cover 14 can be opened first, so that the operator can load the sliding seat 21, the one-way valve 3 and the lubricating liquid into the fixing seat 13, and then close the sealing cover 14, thereby improving the convenience of assembling the growing rod.

[0065] In one example, if Figure 2 and Figure 3 As shown, the sealing cover 14 is connected to the fixing seat 13 by threaded engagement, thereby making it easy to install the fixing seat 13 and the sealing cover 14, and having a simple structure.

[0066] In order to further improve the sealing effect of the accommodating cavity 11, the growth rod also includes a third sealing ring 15, which is arranged in the accommodating cavity 11, and the third sealing ring 15 is clamped between the sealing cover 14 and the fixed seat 13, and the third sealing ring 15 is against the inner circumferential wall of the second rod 2, thereby reducing the probability of leakage of the lubricating fluid from the gap between the fixed seat 13 and the sealing cover 14, and the gap between the second rod body 22 and the sealing cover 14, so that the sealing effect of the growth rod is better.

[0067] It is understandable that, during the assembly of the growth rod, since the installation gap between the sliding seat 21 and the accommodating chamber 11 is small and the one-way valve 3 has a one-way conduction characteristic, the air in the second chamber 112 is not easy to be discharged as the sliding seat 21 descends. Therefore, it is necessary to use an installation tool to put the sliding seat 21 into the bottom of the accommodating chamber 11.

[0068] Specifically, Figure 4 As shown, the installation tool includes an airbag head 51 and a hose 52, one end of the hose 52 is connected to the airbag head 51, and the other end of the hose 52 is connected to the air source 53. The airbag head 51 is located between the second rod body 22 and the valve core 32. The air source 53 inflates the airbag head 51 through the hose 52. The valve core 32 moves downward under the pressure of the airbag head 51 to open the first channel 211, so that the pressure of the first chamber 111 and the second chamber 112 are balanced, and it is convenient to put the sliding seat 21 into the bottom of the accommodating chamber 11. After the sliding seat 21 is put into the bottom of the accommodating chamber 11, the medium is injected into the accommodating chamber 11 so that the medium can fill the first chamber 111 and the second chamber 112, and then the air source 53 is controlled to deflate the airbag head 51, and the airbag head 51 and the hose 52 are removed from the accommodating chamber 11, and the sealing cover 14 is installed, thereby completing the assembly of the growth rod.

[0069] like Figure 2 and Figure 3 As shown, when the spine is subjected to growth force or external pulling force, the second rod 2 is forced to move upward relative to the first rod 1. In the accommodating chamber 11, the upper end surface of the sliding seat 21 is compressed by the space to generate positive pressure, and the lower end surface of the sliding seat 21 is negative pressure. When the pressure difference of the valve core 32 of the one-way valve 3 reaches the preset traction force, the valve core 32 opens, and the lubricating fluid in the first chamber 111 flows through the first hole 221, the second hole 222, and the first channel 211 and enters the second chamber 112. As the growth force of the spine weakens or the external pulling force stops, the pressure on the upper end surface and the pressure on the lower end surface of the sliding seat 21 also reach equilibrium. The one-way valve 3 is closed under the elastic force of the elastic member 31, and the second rod 2 is extended upward.

[0070] The second rod 2 can be extended and "grown" infinitely within the maximum extension range, and the maximum extension "growth" range can be designed and manufactured according to actual needs. After the growth rod completes the extension "growth", it can also effectively support the force from the upper vertebra to the lower vertebra of the spine. When the second rod 2 is subjected to downward force and moves downward relative to the first rod 1, positive pressure is generated on the lower end face of the sliding seat 21 due to space compression, and negative pressure is generated on the upper end face of the sliding seat 21. The valve core 32 of the one-way valve 3 cannot be opened due to this pressure difference, thereby achieving effective support after the growth rod is extended and "grown".

[0071] like Figure 1 As shown, an orthopedic fixation system of another embodiment of the present invention includes a growing rod and at least two pedicle screws 4. The growing rod is the growing rod of the present invention. At least one pedicle screw 4 is connected to the first rod 1 and the second rod 2. The pedicle screw 4 can be connected to the human spine.

[0072] According to the orthopedic fixation system of the embodiment of the present invention, when the growth rod is implanted on the patient's spine, and with the growth of the spine or being pulled in vitro, one of the first rod 1 and the second rod 2 will be subjected to a traction force away from the other, and when the traction force is greater than the preset traction force, the one-way valve 3 can allow the medium in the first chamber 111 to flow toward the second chamber 112, so that the space of the second chamber 112 increases, and the space of the first chamber 111 decreases synchronously, thereby allowing the first rod 1 and the second rod 2 to move away from each other, so that the growth rod can be synchronously extended with the growth of the spine. Since the one-way valve 3 has the characteristic of unidirectional conduction, the medium in the second chamber 112 will not flow back into the first chamber 111, thereby improving the stability of the support after the growth rod is extended. Therefore, the orthopedic fixation system of the embodiment of the present invention can be extended accordingly with the growth of the patient's spine, which is conducive to reducing the risks of complications caused by repeated open surgery, and the spinal correction effect is better.

[0073] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0074] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0075] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0076] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0077] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0078] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A growing rod, characterized in that: include: A first rod, wherein a first end of the first rod is provided with a receiving cavity, and the receiving cavity has a first chamber and a second chamber; a second rod, wherein a sliding seat is provided at a first end of the second rod, and the sliding seat is arranged in the accommodating cavity for sliding along the axial direction of the first rod, the first chamber and the second chamber are arranged on both sides of the axial direction of the sliding seat respectively, and the second chamber is closer to the second end of the first rod than the first chamber; A one-way valve is arranged on the sliding seat, and when a traction force acting on one of the first rod and the second rod away from the other is greater than a preset traction force, the one-way valve can allow the medium in the first chamber to flow toward the second chamber.

2. The growing rod according to claim 1, characterized in that A first channel is provided in the sliding seat, and two ends of the first channel are respectively connected to the first chamber and the second chamber. The one-way valve includes an elastic member and a valve core. The valve core is provided in the first channel and connected to the elastic member. The elastic member has an elastic force for driving the valve core to close the first channel. The elastic force is equal to the preset traction force. When the traction force is greater than the preset traction force, the valve core makes the first channel conductive.

3. The growing rod according to claim 2, characterized in that The first port of the first channel is communicated with the first chamber, the second port of the first channel is communicated with the second chamber, the valve core has a first sealing surface, when the traction force is greater than the preset traction force, the first sealing surface is spaced apart from the first port, when the traction force is less than or equal to the preset traction force, the first sealing surface abuts against the first port.

4. The growing rod according to claim 3, characterized in that The first sealing surface is a conical surface, and the conical surface is arranged to gradually narrow along the direction from the second port to the first port; And / or, the valve core includes a core body and a first sealing ring, the first sealing ring is sleeved on the core body, and the first sealing surface is formed on the first sealing ring.

5. The growing rod according to claim 3, characterized in that The one-way valve further includes a limiter, which is disposed in the first channel and adjacent to the second port. One end of the elastic member is connected to the valve core, and the other end of the elastic member is connected to the limiter.

6. The growing rod according to claim 5, characterized in that The outer wall surface of the limiting member is threadably matched with the inner wall surface of the first channel; And / or, a mounting groove is provided at one end of the limiting member adjacent to the valve core, and the other end of the elastic member abuts against the mounting groove.

7. The growing rod according to claim 2, characterized in that A first hole and a second hole are provided in the second rod, the first hole extends radially along the second rod, the second hole extends axially along the second rod, the radial outer end of the first hole is communicated with the first chamber, the radial inner end of the first hole is communicated with the second hole, and the second hole is communicated with the first channel.

8. The growing rod according to claim 1, characterized in that The one-way valve further comprises a second sealing ring, the second sealing ring is sleeved on the outer peripheral wall of the sliding seat, and the outer peripheral wall of the second sealing ring abuts against the inner peripheral wall of the accommodating cavity; And / or, the first chamber and the second chamber are both filled with a medium; And / or, in a cross section orthogonal to the first rod, the cross-sectional profiles of the accommodating cavity and the sliding seat are both polygonal, and the sliding seat is non-rotatably matched with the accommodating cavity.

9. The growing rod according to claim 1, wherein: The first rod comprises a first rod body, a fixing seat and a sealing cover, wherein the fixing seat is arranged at the end of the first rod body, the sealing cover is detachably mounted at an end of the fixing seat away from the first rod body, and the sealing cover and the fixing seat enclose the accommodating cavity; And / or, the first rod includes a fixing seat and a sealing cover, the sealing cover and the fixing seat together form the accommodating cavity, the growing rod also includes a third sealing ring, the third sealing ring is arranged in the accommodating cavity, the third sealing ring is clamped between the sealing cover and the fixing seat, and the third sealing ring is against the inner circumferential wall of the second rod.

10. An orthopedic fixation system, characterized in that: include: A growing rod, wherein the growing rod is the growing rod according to any one of claims 1 to 9; At least two pedicle screws, each of the first rod and the second rod is connected with at least one pedicle screw.

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