Spinal anterior and posterior three-column integrated internal fixation device

Abstract

The utility model discloses a kind of anterior and posterior three-column integrated internal fixation devices of spine, including main nail, nail head nut, dead bolt, nail tail connecting system, nail head connecting system, main nail includes main nail body, nail head and nail tail being arranged at both ends of main nail body, and the outer periphery of main nail body is provided with self-tapping thread;Nail head nut is screwed in the nail head one end of main nail, and nail head nut is equipped with along the radial extension's rod through hole and rod slot, and the inner periphery wall of rod slot is provided with internal thread, and the top edge of nail head nut is symmetrically provided with two breakable blades;Dead bolt is inclined and screwed on the nail head nut, and dead bolt is in contact with main nail.By the three-column integrated internal fixation of vertebral body, pedicle, lamina accessory of spine, the strength of internal fixation of spine is improved, and the operation efficiency and curative effect are improved;And the setting of dead bolt forms oblique compacting force, improves the connection stability of main nail and nail head nut, and the setting of breakable blade facilitates the operation of nail head nut.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically a three-column internal fixation device for anterior and posterior spinal approaches. Background Technology

[0002] Spinal internal fixation materials include cervical internal fixation devices, currently mainly divided into anterior, posterior, and lateral internal fixation devices. There is no single integrated anterior-posterior three-column internal fixation device. Existing anterior fixation systems cannot fix the posterior column, resulting in weak anti-rotation / lateral bending capabilities; posterior fixation systems cannot effectively support the anterior column, leading to easy subsidence or screw breakage; posterior combined fixation systems result in greater surgical trauma, double the surgical time, and more complications. In terms of reliability, neither anterior nor posterior internal fixation, nor even combined anterior-posterior fixation, can completely achieve the ideal, thoroughly reliable three-column internal fixation of the spine. Utility Model Content

[0003] To address the shortcomings of existing technologies, this invention provides a three-column internal fixation device for anterior and posterior spinal approaches. By simultaneously and integrally fixing the vertebral body, pedicle, and lamina appendages of the spine, it improves the strength of spinal internal fixation, simplifies the surgical procedure, increases surgical efficiency, reduces surgical trauma, saves surgical time, reduces surgical bleeding, and improves surgical efficacy. Furthermore, this invention employs a locking bolt obliquely screwed into the screw head nut, abutting against the main screw to form an oblique clamping force, improving the connection stability between the main screw and the screw head nut, enhancing the screw head nut's resistance to torsion and pull-out, and preventing loosening of the screw head nut after prolonged use. The design of a breakable blade facilitates the operation of the screw head nut; after operation, the breakable blade can be quickly broken off, avoiding subsequent interference with the instruments.

[0004] This utility model provides a three-column internal fixation device for anterior and posterior spinal approaches, comprising:

[0005] The main nail includes a main nail body, a nail head and a nail tail disposed at both ends of the main nail body, and the outer periphery of the main nail body is provided with self-tapping threads;

[0006] A nail head nut is screwed onto one end of the nail head of the main nail. The nail head nut has a radially extending through hole for placing a rod and a groove for placing a rod. The inner circumferential wall of the groove for placing a rod is provided with an internal thread. Two breakable blades are symmetrically arranged on the top edge of the nail head nut.

[0007] A locking bolt is obliquely screwed onto the nail head nut, and the locking bolt abuts against the main nail.

[0008] The anterior and posterior spinal three-column internal fixation device of this utility model also includes a screw tail connection system for connecting the tails of multiple main screws and a screw head connection system for connecting the heads of multiple main screws.

[0009] The two breakable blades are located on both sides of the extension direction of the rod slot, and the root of the breakable blade is provided with a preset fracture groove.

[0010] The locking bolt forms an angle of 30° to 60° with the axis of the nail head nut.

[0011] The locking bolts are provided in two sets, and the two sets of locking bolts are symmetrically arranged on the nail head nut.

[0012] The head of the main nail is provided with an internal threaded hole, which extends to the main nail body, and the length of the internal threaded section is 8mm to 30mm.

[0013] The main nail's tail includes a tail body, and a "U-shaped" groove is provided at one end of the tail body away from the main nail body. The inner sidewall of the "U-shaped" groove is provided with internal threads.

[0014] A ball head is provided at one end of the main nail body near the nail tail, and a ball hole adapted to the ball head is provided on the nail tail body.

[0015] The nail tail connection system is a pressure locking plate, which is provided with multiple adjustment holes, including multiple sub-holes that are interconnected and extend in different directions.

[0016] The diameter of the main nail body is 3mm to 7.5mm, and the length is 30mm to 80mm;

[0017] The diameter of the nail head nut is 8mm larger than the diameter of the main nail body;

[0018] The diameter of the through hole for placing the rod and the distance between the two side walls of the groove for placing the rod are 3mm to 7mm.

[0019] The locking bolt has a diameter of 2.5 mm and a length of 5 mm;

[0020] The length of the breakable blade is 5-15mm.

[0021] Compared with the prior art, the advantages of this utility model are as follows:

[0022] 1. The three-column internal fixation device for anterior and posterior spinal approaches provided by this utility model improves the internal fixation strength of the spine by simultaneously and integrally fixing the vertebral body, pedicle, and lamina attachments of the spine. It also simplifies the surgical procedure, increases surgical efficiency, reduces surgical trauma, saves surgical time, reduces surgical bleeding, and improves surgical efficacy. Furthermore, this utility model uses a locking bolt that is obliquely screwed into the screw head nut and abuts against the main screw, forming an oblique clamping force. This improves the connection stability between the main screw and the screw head nut, enhances the screw head nut's resistance to torsion and pull-out, and prevents loosening of the screw head nut after prolonged use. The design of the breakable blade facilitates the operation of the screw head nut; after the operation is completed, the breakable blade can be quickly broken off, avoiding subsequent interference with the instruments.

[0023] 2. The main nail of this utility model has an internal threaded hole at one end of the nail head, which can add a spinal internal fixation method that is connected to the anterior or posterior approach by screws or steel plates, thereby improving practicality. The length of the internal threaded hole is 8mm to 30mm, which makes most of the main nail body maintain a solid structure and ensures the overall strength of the main nail. Attached Figure Description

[0024] Appendix Figure 1 This is a schematic diagram of the structure of this utility model.

[0025] Appendix Figure 2 This is a schematic diagram of the structure of the nail head nut of this utility model.

[0026] Appendix Figure 3 This is a schematic diagram of the pressure locking plate of this utility model.

[0027] Appendix Figure 4 This is a cross-sectional structural diagram of the present invention.

[0028] Appendix Figure 5 This is one of the cross-sectional structural diagrams of the nail tail and the second nail rod of this utility model.

[0029] Appendix Figure 6 This is the second cross-sectional view of the structure of the nail tail and the second nail rod of this utility model.

[0030] The following labels are shown in the attached diagram: 1. Main nail; 11. Main nail body; 12. Nail head; 13. Nail tail; 131. Nail tail body; 132. "U" groove; 133. Ball hole; 14. Internal threaded hole; 15. Ball head; 2. Nail head nut; 21. Rod placement through hole; 22. Rod placement groove; 23. Breakable leaf; 24. Pre-set fracture groove; 3. Locking bolt; 4. Nail tail connection system; 41. Pressure locking plate; 42. Adjustment hole; 421. First dividing hole; 422. Second dividing hole; 43. Second nail rod; 44. Second nut; 5. Nail head connection system; 51. First nail rod; 52. First nut; 6. First screw; 7. First steel plate. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the described embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0032] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar words used in this utility model specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] like Figure 1-6 As shown, this utility model provides a three-column internal fixation device for anterior and posterior spinal surgery, including a main nail 1, a nail head nut 2, and a locking bolt 3. The main nail 1 includes a main nail body 11, a nail head 12 and a nail tail 13 disposed at both ends of the main nail body 11. The outer periphery of the main nail body 11 is provided with self-tapping threads to construct a self-tapping nail body. The nail head nut 2 is screwed to one end of the nail head 12 of the main nail 1. The nail head nut 2 is provided with a radially extending rod placement through hole 21 and a rod placement slot 22. The inner peripheral wall of the rod placement slot 22 is provided with internal threads. A first nail rod 51 (such as a titanium rod) can be placed in both the rod placement through hole 21 and the rod placement slot 22 to provide two rod insertion methods for connecting one end of the nail head 12 of multiple main nails 1. After the first nail rod 51 is inserted into the rod placement slot 22, the first nut 52 is screwed into the rod placement slot 22 to fix the first nail rod 51. Two breakable blades 23 are symmetrically arranged on the edge of the nail head nut 2. The locking bolt 3 is obliquely screwed onto the nail head nut 2, and the locking bolt 3 abuts against the main nail 1 to achieve a tight fixation between the nail head nut 2 and the main nail 1.

[0034] The anterior and posterior spinal three-column internal fixation device of this utility model also includes a nail tail connection system 4 for connecting multiple main nails 1 nail tails 13, and a nail head connection system 5 for connecting multiple main nails 1 nail heads 12.

[0035] This utility model employs a locking bolt 3 that is obliquely screwed into the nail head nut 2 and abuts against the main nail 1 to form an oblique clamping force, thereby improving the connection stability between the main nail 1 and the nail head nut 2, enhancing the nail head nut 2's resistance to torsion and pull-out, and preventing the nail head nut 2 from loosening after prolonged use. The design of the breakable blade 23 facilitates the operation of the nail head nut 2, and after the operation is completed, the breakable blade 23 can be quickly broken off to avoid subsequent interference with the instrument.

[0036] The three-column internal fixation device for anterior and posterior spinal approaches provided by this utility model can be implanted first via the anterior approach: implanted from the front of the vertebral body, passing through the vertebral body and pedicle, and exiting through the posterior lamina appendage, with one end of the main screw 12 leaving an appropriate length (e.g., 6mm for cervical spine, 8mm for thoracic spine, and 10mm for lumbar spine); after completing the anterior approach operation, the screw head nut 2 is used for posterior internal fixation, which can be performed percutaneously or openly in one or two stages to form an integrated anterior, middle, and posterior three-column fixation. The screw tail connection system 4 can be a steel plate, zero-notch, titanium mesh, artificial vertebral body, or other devices to fix the screw, with an adjustable screw track; a 3D guide plate can also be used to fix the screw track; the screw head connection system 5 uses a connectable and adjustable universal bolt to connect the first screw rod 51 (e.g., a titanium rod) to form a fixation, satisfying the percutaneous placement of the nut and rod. This utility model device travels retrogradely through the vertebral body, past the pedicle, and then to the posterior lamina. It requires that the needle entry point, direction, and depth of the vertebral body be determined during the operation. Based on the preoperative measurements, the specific specifications of each screw in the device system are initially selected for clinical use.

[0037] This utility model device is also applicable to posterior-path implanted spinal internal fixation, that is, the original posterior pedicle screw system, combined with the improved design of the screw head nut 2 of this utility model, forms a posterior-anterior spinal internal fixation device.

[0038] This utility model presents an integrated anterior and posterior spinal internal fixation device. By simultaneously and integrally fixing the vertebral body, pedicle, and lamina of the spine, it improves the strength of spinal internal fixation, simplifies the surgical procedure, increases surgical efficiency, reduces surgical trauma, saves surgical time, reduces surgical bleeding, and improves surgical efficacy.

[0039] In one embodiment, the two breakable blades 23 are located on both sides of the extension direction of the rod slot 22 to avoid affecting the rod insertion operation in the rod slot 22. The root of the breakable blade 23 is provided with a preset fracture groove 24 to facilitate the breaking operation of the breakable blade 23.

[0040] In one embodiment, the locking bolt 3 forms an angle of 30°-60° with the axis of the nail head nut 2 to ensure the connection stability between the main nail 1 and the nail head nut 2.

[0041] In one embodiment, two sets of locking bolts 3 are provided, and the two sets of locking bolts 3 are symmetrically arranged on the nail head nut 2 along the central axis of the nail head nut 2, further ensuring the connection stability between the main nail 1 and the nail head nut 2.

[0042] In one embodiment, the head 12 of the main nail 1 is provided with an internally threaded hole 14 at one end, the internally threaded hole 14 extending to the main nail body 11, and the length of the internally threaded hole 14 is 8mm to 30mm. For example, when used for cervical spine internal fixation, the length of the internally threaded hole 14 is: 8mm, 10mm, 12mm, 14mm, 16mm; when used for thoracic spine internal fixation, the length of the internally threaded hole 14 is: 14mm, 16mm, 18mm, 20mm, 22mm; when used for lumbar spine internal fixation, the length of the internally threaded hole 14 is: 20mm, 22mm, 24mm, 26mm, 28mm, 30mm.

[0043] In this embodiment, the head 12 of the main nail 1 is provided with an internally threaded hole 14 at one end to increase the connection method with the anterior or posterior screws; the length of the internally threaded hole 14 is 8mm to 30mm, so that most of the main nail body 11 remains a solid structure, ensuring the overall strength of the main nail 1. During the surgical procedure: one end of the head 12 of the main nail 1 is brought to the anterior or posterior bone surface, protruding no more than 2mm from the bone surface to prevent damage to other tissues on the bone surface, especially the anterior spinal tissues; then, in the first or second stage, using an anterior or posterior approach, a first screw 6 of appropriate length is screwed into the internally threaded hole 14 at one end of the head 12 of the retained main nail 1, and the first screws 6 are connected by a first steel plate 7, so that the anterior and posterior fixation is completely integrated. The advantages of this design are: if a simple posterior or anterior approach cannot fully confirm the effectiveness of the treatment, and posterior or anterior fixation is required first, leaving the screw heads exposed, the condition can be observed. If, after observation, a second surgery is still needed, then anterior or posterior internal fixation can be performed to connect with the previous internal fixation to form a unified internal fixation system. Another scenario is when, after several years of internal fixation, the site develops lesions again, or internal fixation fails, requiring revision. In this case, a new surgical approach can be used to avoid the significant surgical difficulty and nerve damage risks associated with a second surgery via the same approach, while still achieving a secure unified internal fixation system with the original internal fixation.

[0044] In one embodiment, the nail tail connection system 4 includes a pressure locking plate 41, on which a plurality of adjustment holes 42 are provided. Each adjustment hole 42 includes a plurality of branch holes extending in different directions and communicating with each other. For example, the adjustment holes 42 include a first branch hole 421 extending in a first direction and a plurality of second branch holes 422 extending in a second direction, wherein the first direction is perpendicular to or inclined to the second direction. In this case, the nail tail 13 of the main nail 1 can be a studded round-head nail tail 131, and the pressure locking plate 41 is used to fix the nail tails of the plurality of main nails 1.

[0045] In this embodiment, a pressure locking plate 41 with adjustable pin channels is designed. The setting of adjustment holes 42 greatly increases the position of the pin channels to adapt to various needs. Based on the standard specifications of anterior cervical, thoracic, and lumbar spine plates, it is adjustable and can be set in various styles and specifications as needed. The multi-hole plate can adapt to various needs. Alternatively, a pin placement template can be made according to the preoperative imaging system, and the plate system can be customized according to the pin placement position.

[0046] In one embodiment, the tail 13 of the main nail 1 includes a tail body 131. A U-shaped groove 132 is provided at the end of the tail body 131 facing away from the main nail body 11, and the inner wall of the U-shaped groove 132 is provided with internal threads. In this embodiment, the tail connection system 4 includes a second nail bar 43. The U-shaped groove 132 is used to insert the second nail bar 43 and lock it in place by a second nut 44. The diameter of the second nail bar 43 is 3mm to 7mm. For example, the diameter of the second nail bar 51 is: 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, or 7mm.

[0047] In one embodiment, a ball head 15 is provided at one end of the main nail body 11 near the nail tail 13, and a ball hole 133 adapted to the ball head 15 is provided on the nail tail body 131 to realize flexible adjustment of the nail tail 13 within a certain angle range to meet the needs of different spinal internal fixation.

[0048] In one embodiment, the diameter of the main nail body 11 is 3mm to 7.5mm, and the length is 30mm to 80mm; the diameter of the nail head nut 2 is 8mm larger than the diameter of the main nail body 11; the diameter of the rod-holding through hole 21 and the distance between the two side walls of the rod-holding groove 22 are 3mm to 7mm, adapted to the connection of the second nail rod 51 with a diameter of 3mm to 7mm. For example, the diameter of the second nail rod 51 is: 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm; the diameter of the locking bolt 3 is 2.5mm, and the length is 5mm; the length of the breakable blade 23 on the nail head nut 2 is 5-15mm; and the height of the threaded section of the nail head nut 2 is 8-12mm.

[0049] For example, when used for anterior-posterior or posterior-anterior three-column internal fixation of the cervical spine, the diameter of the main nail body 11 can be 3mm, 3.5mm, 4mm, or 4.5mm, and the length of the main nail body 11 can be 30mm, 35mm, 40mm, 45mm, or 50mm; the thread height of the nail head nut 2 is 8mm.

[0050] When used for anterior-posterior or posteroanterior three-column internal fixation of the thoracic spine, the diameter of the main nail 1 can be 4mm, 4.5mm, 5mm, or 5.5mm, the length of the main nail 1 can be 40mm, 45mm, 50mm, 55mm, or 65mm, and the thread height of the nail head nut 2 is 10mm.

[0051] When used for anterior-posterior or posterior-anterior three-column internal fixation of the lumbar spine, the diameter of the main nail 1 can be 5.5mm, 6mm, 6.5mm, 7mm, or 7.5mm, the length of the main nail 1 can be 50mm, 55mm, 60mm, 65mm, 75mm, or 80mm, and the thread height of the nail head nut 2 is 12mm.

[0052] Those skilled in the art should understand that the specific embodiments described above are merely examples and not limitations. Various modifications, combinations, partial combinations, and substitutions can be made to the embodiments of this utility model according to design requirements and other factors, as long as they are within the scope of the appended claims or their equivalents, and thus fall within the scope of the rights to be protected by this utility model.

Claims

1. A three-column internal fixation device for anterior and posterior spinal approaches, characterized in that, include: The main nail includes a main nail body, a nail head and a nail tail disposed at both ends of the main nail body, and the outer periphery of the main nail body is provided with self-tapping threads; A nail head nut is screwed onto one end of the nail head of the main nail. The nail head nut has a radially extending through hole for placing a rod and a groove for placing a rod. The inner circumferential wall of the groove for placing a rod is provided with an internal thread. Two breakable blades are symmetrically arranged on the top edge of the nail head nut. A locking bolt is obliquely screwed onto the nail head nut, and the locking bolt abuts against the main nail.

2. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, It also includes a nail tail connection system for connecting multiple main nail tails and a nail head connection system for connecting multiple main nail heads.

3. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The two breakable blades are located on both sides of the extension direction of the rod slot, and the root of the breakable blade is provided with a preset fracture groove.

4. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The locking bolt forms an angle of 30° to 60° with the axis of the nail head nut.

5. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The locking bolts are provided in two sets, and the two sets of locking bolts are symmetrically arranged on the nail head nut.

6. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The head of the main nail is provided with an internal threaded hole, which extends to the main nail body, and the length of the internal threaded section is 8mm to 30mm.

7. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The main nail's tail includes a tail body, and a "U-shaped" groove is provided at one end of the tail body away from the main nail body. The inner sidewall of the "U-shaped" groove is provided with internal threads.

8. The spinal anterior and posterior three-column internal fixation device according to claim 7, characterized in that, A ball head is provided at one end of the main nail body near the nail tail, and a ball hole adapted to the ball head is provided on the nail tail body.

9. A three-column internal fixation device for anterior and posterior spinal approaches according to claim 2, characterized in that, The nail tail connection system includes a pressure locking plate, which is provided with multiple adjustment holes, each adjustment hole including multiple sub-holes that are interconnected and extend in different directions.

10. The spinal anterior and posterior three-column internal fixation device according to claim 1, characterized in that, The diameter of the main nail body is 3mm to 7.5mm, and the length is 30mm to 80mm; The diameter of the nail head nut is 8mm larger than the diameter of the main nail body; The diameter of the through hole for placing the rod and the distance between the two side walls of the groove for placing the rod are 3mm to 7mm. The locking bolt has a diameter of 2.5 mm and a length of 5 mm; The length of the breakable blade is 5-15mm.

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