Internal fixing device for spine

Abstract

The utility model belongs to the technical field of medical instruments, and discloses a spine internal fixing device. The internal fixing device for the spine comprises a connecting rod, a compression nut and at least two pedicle screws, the connecting rod is made of flexible materials so that the bending degree of the connecting rod can be adjusted, positioning grooves are formed in the pedicle screws, the connecting rod is arranged in the positioning grooves in a penetrating mode, the compression nut is arranged in the positioning grooves in a threaded fit mode, and the connecting rod is made of flexible materials. And the connecting rod is pressed in the positioning groove in an abutting manner. The connecting rod is made of a flexible material, can provide mechanical properties better matched with human bones, and has lower rigidity, so that the risk of complications is reduced; the flexibility of the flexible connecting rod can be adjusted as required, so that the use requirements of different patients and different scenes can be better met, and medical image evaluation cannot be influenced; the positioning grooves can play a role in positioning the connecting rods, so that the connecting effect and the stability are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of medical instruments, in particular to a spinal internal fixation device. Background Art

[0002] Posterior spinal fixation is a common method for treating spinal diseases or injuries. Spinal fixation devices are used in posterior spinal fixation surgery to restore the physiological curvature of the vertebrae that have slipped, displaced, lordotic, kyphotic or scoliotic to achieve correction, stabilize the spine and promote healing.

[0003] At present, the connecting rods used in posterior spinal fixation systems are usually made of metal materials, such as titanium alloy. These metal connecting rods have high rigidity and strength and can provide good stability and support. However, due to their high rigidity and the large difference in rigidity with the human skeleton, the metal connecting rods do not match the surrounding bones, causing implant-related complications such as osteoporosis, loose fixation, and pain. Secondly, metal connecting rods may cause imaging artifacts, making postoperative imaging evaluation difficult. In addition, the use of metal connecting rods also has certain surgical difficulties and complexities, and additional surgical steps are required to ensure the correct installation and adjustment of the connecting rods. Utility Model Content

[0004] The utility model aims to provide a spinal internal fixation device, which is used to solve the problems that the existing metal connecting rods are prone to cause complications, affect postoperative imaging evaluation and increase the difficulty of surgery.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] The spinal internal fixation device comprises a connecting rod, a clamping nut and at least two pedicle screws, wherein the connecting rod is made of a flexible material so that the curvature of the connecting rod is adjustable, the pedicle screw is provided with a positioning groove, the connecting rod is inserted into the positioning groove, the clamping nut is threadedly engaged in the positioning groove, and presses the connecting rod into the positioning groove.

[0007] As an optional solution of the above-mentioned spinal internal fixation device, the pedicle screw includes a head and a rod, the head includes two limiting arms arranged opposite to each other, the positioning groove is formed between the two limiting arms, and the connecting rod is located between the two limiting arms.

[0008] As an optional solution of the above spinal internal fixation device, the connecting rod is made of polycarbonate polyurethane.

[0009] As an optional solution of the above spinal internal fixation device, the cross-sectional areas of the connecting rods are equal along the length direction.

[0010] As an optional solution of the above spinal internal fixation device, the cross-section of the connecting rod perpendicular to its length direction is circular, elliptical, oval or polygonal;

[0011] Alternatively, a cross section of the connecting rod perpendicular to its length direction includes a semicircular portion and a rectangular portion, and a diameter of the semicircular portion is equal to and coincides with a side length of the rectangular portion.

[0012] As an optional solution of the above-mentioned spinal internal fixation device, the connecting rod includes a first rod segment and a second rod segment, the first rod segment includes a first cross-section perpendicular to its length direction, the second rod segment includes a second cross-section perpendicular to its length direction, and the area of ​​the first cross-section is greater than the area of ​​the second cross-section.

[0013] As an optional solution of the above-mentioned spinal internal fixation device, the first rod segment and the second rod segment are both equipped with the pedicle screws, and the depth of the positioning groove in the pedicle screw located in the first rod segment is greater than the depth of the positioning groove in the pedicle screw located in the second rod segment.

[0014] As an optional solution of the above spinal internal fixation device, the shape of the second cross section is circular, and the area of ​​the first cross section is oval.

[0015] As an optional solution of the above-mentioned spinal internal fixation device, the first cross-section includes a first semicircular portion and a first rectangular portion, the diameter of the first semicircular portion is equal to and coincides with a side length of the first rectangular portion, the second cross-section includes a second semicircular portion and a second rectangular portion, the diameter of the second semicircular portion is equal to and coincides with a side length of the second rectangular portion, and a side of the first rectangular portion facing away from the first semicircular portion coincides with a side of the second rectangular portion facing away from the second semicircular portion.

[0016] As an optional solution of the above spinal internal fixation device, the orthographic projection of the first section covers the orthographic projection of the second section.

[0017] Beneficial effects of the utility model:

[0018] In the spinal internal fixation device provided by the utility model, the connecting rod is made of a flexible material, which can provide mechanical properties that are more compatible with human bones and have lower rigidity to reduce the risk of complications. In addition, the flexible connecting rod can adjust its curvature as needed to better meet the use requirements of different patients and different scenarios, allowing adjacent segments to be connected with greater flexibility when fusion is required, achieving dynamic stability, better adapting to specific disease patterns, and protecting adjacent vertebrae and intervertebral discs from excessive wear.

[0019] The pedicle screw is provided with a positioning groove, which is used to cooperate with the connecting rod to position the connecting rod, thereby improving the stability and reliability of the spinal internal fixation device. Afterwards, the pedicle screw and the connecting rod are fixedly connected by a compression nut, and the connection is firm and easy to operate.

[0020] In this embodiment, the clamping nut is completely located in the positioning groove, which can prevent the clamping nut from interfering with bones or other structures after protruding, thereby affecting the fixing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a front view of the spinal internal fixation device provided by the utility model;

[0022] Figure 2 It is a top view of the spinal internal fixation device provided by the utility model;

[0023] Figure 3 This is a front view of the pedicle screw provided by the utility model;

[0024] Figure 4 This is a front view of the first connecting rod provided by the utility model;

[0025] Figure 5 This is a front view of the second connecting rod provided by the utility model;

[0026] Figure 6 This is the first cross-sectional shape of the connecting rod provided by the utility model;

[0027] Figure 7 This is the second cross-sectional shape of the connecting rod provided by the utility model;

[0028] Figure 8 It is a schematic structural diagram of the connecting rod and the pedicle screw after being assembled with the first cross-sectional shape provided by the utility model;

[0029] Fig. 9 It is a schematic structural diagram of the connecting rod and the pedicle screw after being assembled with the second cross-sectional shape provided by the utility model;

[0030] Fig.10 This is a front view of a third connecting rod provided by the utility model;

[0031] Fig.11 This is a front view of a fourth connecting rod provided by the utility model;

[0032] Fig.12 This is the third cross-sectional shape of the connecting rod provided by the utility model;

[0033] Fig.13 This is the fourth cross-sectional shape of the connecting rod provided by the utility model;

[0034] Fig.14 This is a schematic diagram of the structure of the connecting rod and the pedicle screw after being assembled with the third cross-sectional shape provided by the utility model;

[0035] Fig.15 It is a schematic structural diagram of the assembly of a connecting rod and a pedicle screw of the fourth cross-sectional shape provided by the utility model.

[0036] In the figure:

[0037] 10. Pedicle screw; 11. Rod; 12. Head; 121. Limiting arm; 122. Positioning groove; 20. Connecting rod; 21. First rod segment; 211. First cross section; 22. Second rod segment; 221. Second cross section; 30. Compression nut. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0039] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0041] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0042] This embodiment provides a spinal internal fixation device, such as Figure 1 and Figure 2 As shown, the spinal internal fixation device includes a connecting rod 20, a clamping nut 30 and at least two pedicle screws 10. The connecting rod 20 is made of a flexible material so that the curvature of the connecting rod 20 is adjustable, and a positioning groove 122 is provided on the pedicle screw 10. The connecting rod 20 is inserted into the positioning groove 122, and the clamping nut 30 cooperates with the positioning groove 122. The clamping nut 30 is located above the connecting rod 20. After the clamping nut 30 cooperates with the positioning groove 122, the connecting rod 20 can be pressed into the positioning groove 122 of the pedicle screw 10. Optionally, the clamping nut 30 has an external thread, and the positioning groove 122 is provided with an internal thread, so that the clamping nut 30 can be threadedly matched with the positioning groove 122 to be fixed.

[0043] The connecting rod 20 is made of a flexible material. The flexible connecting rod 20 can provide mechanical properties that are more compatible with human bones and has lower rigidity to reduce the risk of complications. In addition, the flexible connecting rod 20 can adjust its curvature as needed to better meet the use requirements of different patients and different scenarios, allowing adjacent segments to be connected with greater flexibility when fusion is required, achieving dynamic stability, better adapting to specific disease patterns, and protecting adjacent vertebrae and intervertebral discs from excessive wear.

[0044] In this embodiment, the connecting rod 20 is made of polycarbonate polyurethane, which not only makes the connecting rod 20 flexible, but also does not affect the feasibility of medical imaging examinations such as magnetic resonance imaging. No additional surgical steps are required to ensure the correct installation and adjustment of the connecting rod 20, which helps to reduce the difficulty of the operation.

[0045] The connecting rod 20 made of polycarbonate polyurethane can have a variety of flexibility, such as high flexibility, medium flexibility and low flexibility, and can be flexibly selected according to the needs of different patients and scenarios during clinical use. Using a connecting rod 20 with corresponding flexibility can shorten the later recovery period and improve the treatment effect.

[0046] In addition, polycarbonate polyurethane has a certain plasticity, and the connecting rod 20 can be pre-bent to simulate the spinal curvature, which can save the surgical step of bending the connecting rod 20 during surgery, thereby improving surgical efficiency and reducing surgical time.

[0047] In other embodiments, the connecting rod 20 may also be made of other polymer materials with mechanical properties closer to those of the human spine to improve the effect of internal fixation.

[0048] In this embodiment, a positioning groove 122 is provided on the pedicle screw 10, and the positioning groove 122 is used to cooperate with the connecting rod 20 to position the connecting rod 20, thereby improving the stability and reliability of the spinal internal fixation device. Afterwards, the pedicle screw 10 and the connecting rod 20 are fixed by the compression nut 30, and the connection is firm and easy to operate.

[0049] In this embodiment, the clamping nut 30 is completely located in the positioning groove 122, which can prevent the clamping nut 30 from interfering with bones or other structures after protruding, thereby affecting the fixing effect.

[0050] like Figure 3 As shown, the pedicle screw 10 includes a head 12 and a rod 11, the head 12 includes two limiting arms 121 arranged opposite to each other, a positioning groove 122 is formed between the two limiting arms 121, and the connecting rod 20 is located between the two limiting arms 121. By forming the limiting groove between the two limiting arms 121, it is convenient for the connecting rod 20 to pass through the positioning groove 122, and the position of the pedicle screw 10 on the connecting rod 20 can be adjusted flexibly according to the use requirements.

[0051] In this embodiment, two pedicle screws 10 are provided on the connecting rod 20. In other embodiments, the number of pedicle screws 10 on the connecting rod 20 can be adjusted according to actual conditions, and can be three, four or more.

[0052] Optionally, the spinal internal fixation device may include two connecting rods 20, each of which is provided with a pedicle screw 10, and the two connecting rods 20 are respectively located on both sides of the spine, and the two connecting rods 20 may be connected by a cross bar.

[0053] like Figure 4 and Figure 5 As shown, the connecting rod 20 can be a straight rod or a curved rod with a certain curvature to better meet the needs of different scenarios and patients.

[0054] Combination Figure 4-Figure 6 As shown, the cross-sectional area of ​​the cross section perpendicular to the length direction of the connecting rod 20 can be equal along the length direction. That is, the connecting rod 20 is of equal thickness along the length direction. This arrangement makes the flexibility of the connecting rod 20 the same at all locations.

[0055] Optionally, the cross-section of the connecting rod 20 perpendicular to its length direction is circular, elliptical, oval or polygonal; Figure 7As shown, the cross section of the connecting rod 20 perpendicular to its length direction may include a semicircular portion and a rectangular portion, and the diameter of the semicircular portion is equal to and coincides with the length of one side of the rectangular portion.

[0056] like Figure 8 and Fig. 9 As shown, after the connecting rod 20 is placed in the positioning groove 122 , the connecting rod 20 abuts against the bottom surface of the positioning groove 122 to improve the fixing effect of the connecting rod 20 and the pedicle screw 10 .

[0057] The cross-sectional shape of the connecting rod 20 perpendicular to the length direction can be set according to actual needs, and different cross-sectional shapes have different effects on the flexibility of the connecting rod 20.

[0058] like Fig.10 and Fig.11 As shown, the connecting rod 20 may also be a stepped structure. Specifically, the connecting rod 20 includes a first rod segment 21 and a second rod segment 22, the first rod segment 21 includes a first cross section 211 perpendicular to its length direction, the second rod segment 22 includes a second cross section 221 perpendicular to its length direction, and the area of ​​the first cross section 211 is greater than the area of ​​the second cross section 221. By dividing the connecting rod 20 into the first rod segment 21 and the second rod segment 22 of different thicknesses, the flexibility of the connecting rod 20 can be made different along its length direction to accommodate the use requirements of more patients or scenarios.

[0059] Preferably, the orthographic projection of the first section 211 covers the orthographic projection of the second section 221. This arrangement allows at least part of the surface of the connecting rod 20 to extend smoothly along its length direction, facilitating the use and positioning of the connecting rod 20. The orthographic projection of the first section 211 is a projection along a direction perpendicular to the first section 211.

[0060] like Fig.12 As shown, the shape of the second section 221 can be circular, and the area of ​​the first section 211 is oval. The oval is a spliced ​​pattern of a rectangle and two semicircles, and the opposite sides of the rectangle are connected to semicircles, and the corresponding side lengths of the rectangle are equal to and coincide with the diameter of the semicircle. Among them, the diameter of the second section 221 can be equal to the semicircular diameter of the oval, and the centers of the two can coincide. This arrangement makes the partial semi-cylindrical surface of the first rod segment 21 flush with the partial cylindrical surface of the second rod segment 22 and connected, so that at least part of the surface of the connecting rod 20 extends smoothly along the length direction, and the partial surface has no protrusions or depressions.

[0061] In some embodiments, Fig.13As shown, the first cross section 211 includes a first semicircular portion and a first rectangular portion, the diameter of the first semicircular portion is equal to and coincides with the length of one side of the first rectangular portion, the second cross section 221 includes a second semicircular portion and a second rectangular portion, the diameter of the second semicircular portion is equal to and coincides with the length of one side of the second rectangular portion, and the side of the first rectangular portion away from the first semicircular portion coincides with the side of the second rectangular portion away from the second semicircular portion. In this arrangement, the three side planes of the first rod segment 21 and the second rod segment 22 partially overlap, which facilitates the matching of the connecting rod 20 with the pedicle screw 10 and the positioning of the connecting rod 20.

[0062] The first rod segment 21 and the second rod segment 22 are both matched with the pedicle screw 10. Since the cross-sectional areas of the first rod segment 21 and the second rod segment 22 are different, in order to ensure the fixing effect of each of the first rod segment 21 and the second rod segment 22 with the pedicle screw 10 thereon, the depth of the positioning groove 122 in the pedicle screw 10 located in the first rod segment 21 is greater than the depth of the positioning groove 122 in the pedicle screw 10 located in the second rod segment 22. That is, the size of the head 12 of the pedicle screw 10 is adapted to the cross-sectional area of ​​the connecting rod 20 matched therewith, so as to ensure the positioning effect of the positioning groove 122 on the connecting rod 20. The depth (the dimension in the length direction of the pedicle screw 10) of the positioning groove 122 in the pedicle screw 10 matched with the second rod segment 22 with a smaller cross-sectional area is less than the depth of the positioning groove 122 in the pedicle screw 10 matched with the first rod segment 21 with a larger cross-sectional area.

[0063] The spinal internal fixation device provided by the utility model uses polycarbonate polyurethane as the material of the connecting rod 20, which can provide better flexibility and mechanical properties, so that the connecting rod 20 is closer to the human body; the connecting rod 20 has three types of flexibility: high, medium and low; the connecting rod 20 is designed to have different flexibility options to meet the spinal needs of different patients; the shape, structure and other aspects of the connecting rod 20 are optimized to further improve the effect of internal fixation.

[0064] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A spinal internal fixation device, characterized in that: The invention comprises a connecting rod (20), a clamping nut (30) and at least two pedicle screws (10); the connecting rod (20) is made of a flexible material so that the curvature of the connecting rod (20) is adjustable; a positioning groove (122) is provided on the pedicle screw (10); the connecting rod (20) is inserted into the positioning groove (122); the clamping nut (30) is threadedly engaged in the positioning groove (122) and presses the connecting rod (20) into the positioning groove (122).

2. The spinal internal fixation device according to claim 1, characterized in that: The pedicle screw (10) comprises a head (12) and a rod (11); the head (12) comprises two limiting arms (121) arranged opposite to each other; the positioning groove (122) is formed between the two limiting arms (121); and the connecting rod (20) is located between the two limiting arms (121).

3. The spinal internal fixation device according to claim 1, characterized in that: The connecting rod (20) is made of polycarbonate polyurethane.

4. The spinal internal fixation device according to any one of claims 1 to 3, characterized in that: The cross-sectional area of ​​the connecting rod (20) is equal along the length direction.

5. The spinal internal fixation device according to claim 4, characterized in that: The cross-section of the connecting rod (20) perpendicular to its length direction is circular, elliptical, oval or polygonal; Alternatively, the cross section of the connecting rod (20) perpendicular to its length direction comprises a semicircular portion and a rectangular portion, and the diameter of the semicircular portion is equal to and coincides with the length of one side of the rectangular portion.

6. The spinal internal fixation device according to any one of claims 1 to 3, characterized in that: The connecting rod (20) comprises a first rod segment (21) and a second rod segment (22); the first rod segment (21) comprises a first cross section (211) perpendicular to its length direction; the second rod segment (22) comprises a second cross section (221) perpendicular to its length direction; the area of ​​the first cross section (211) is greater than the area of ​​the second cross section (221).

7. The spinal internal fixation device according to claim 6, characterized in that: The first rod segment (21) and the second rod segment (22) are both matched with the pedicle screw (10), and the depth of the positioning groove (122) in the pedicle screw (10) located in the first rod segment (21) is greater than the depth of the positioning groove (122) in the pedicle screw (10) located in the second rod segment (22).

8. The spinal internal fixation device according to claim 6, characterized in that: The shape of the second cross section (221) is circular, and the area of ​​the first cross section (211) is oval.

9. The spinal internal fixation device according to claim 6, characterized in that: The first cross section (211) includes a first semicircular portion and a first rectangular portion, the diameter of the first semicircular portion is equal to and coincides with a side length of the first rectangular portion, the second cross section (221) includes a second semicircular portion and a second rectangular portion, the diameter of the second semicircular portion is equal to and coincides with a side length of the second rectangular portion, and a side of the first rectangular portion facing away from the first semicircular portion coincides with a side of the second rectangular portion facing away from the second semicircular portion.

10. The spinal internal fixation device according to claim 6, characterized in that: The orthographic projection of the first section (211) covers the orthographic projection of the second section (221).

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