Cervical vertebra hollow lag screw for operative treatment

Abstract

The invention discloses a cervical vertebra hollow lag screw for operative treatment, and belongs to the field of medical instruments, the cervical vertebra hollow lag screw comprises a screw seat, a screw seat and a lag screw, the upper end of the screw seat is provided with a U-shaped groove for accommodating a fixing rod, and a spherical notch for preventing the screw head from being separated from the lower end of the screw seat is arranged between the screw head and the screw seat; a hexagonal hole is formed in the screw head in the axial direction, a first through hole penetrating through the lag screw is formed in the lag screw in the axial direction, and the hexagonal hole is larger than the first through hole in size. Wide threads are arranged at the end, away from the screw head, of the surface of the screw body, narrow threads are arranged at the end, close to the screw head, of the screw head, and the thread pitch of the wide threads is two times that of the narrow threads. And no thread is arranged between the wide thread and the narrow thread. Two ends of a fracture can be lifted and pressurized, the U-shaped nut is arranged on the rear portion, the thread is arranged close to the nut, and after the U-shaped nut and the connecting rod are fixed together, an injured vertebral body and an adjacent vertebral body can be fixed together, and the effects of pressurizing the fracture end and fixing the fracture end and the adjacent vertebral body are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, and in particular to a hollow traction screw for cervical vertebrae used for surgical treatment. Background Art

[0002] The posterior cervical screws currently used in clinical practice are full-thread solid screws. In clinical practice, we found that the use of full-thread solid screws to fix longitudinal fractures of the cervical pedicle or vertebral body in the coronal plane often increases the separation of the fracture ends. Since traditional lag screws only have the function of pulling and pressurizing, the screw seat does not have a U-shaped groove for accommodating the fixation rod, and cannot be fixed by connecting the rod to achieve the function of fixing the injured vertebra and the adjacent vertebra together, it cannot be used to fix the cervical spine. Summary of the invention

[0003] In order to solve the technical problems in the prior art that partial cervical fractures need to be fixed with pressure and that the current tension screws cannot fix the injured vertebra and adjacent vertebrae, the present invention provides a hollow cervical tension screw for surgical treatment.

[0004] To achieve the above technical solution, the present invention provides a hollow tension screw for surgical treatment of the cervical vertebra, comprising a screw seat, a tension screw is sleeved on the lower end of the screw seat, a U-shaped groove is provided at the upper end of the screw seat for accommodating a fixing rod, the tension screw comprises a screw head located at the lower end of the screw seat and a nail body fixedly connected to the lower end of the screw head, a spherical incision is provided between the screw head and the screw seat for limiting the screw head from escaping from the lower end of the screw seat, an internal thread is provided on the inner wall surface of the screw seat, a reset hole is provided on the side of the screw seat surface close to the screw head; a hexagonal hole is provided in the axial direction of the screw head, a first through hole is provided in the axial direction of the tension screw, and the size of the hexagonal hole is larger than the first through hole; a wide thread is provided at one end of the nail body surface away from the screw head, and a narrow thread is provided at one end of the screw head close to the screw head, and the pitch of the wide thread is twice that of the narrow thread; no thread is provided between the wide thread and the narrow thread.

[0005] Furthermore, a fixing groove corresponding to the U-shaped groove is provided on the screw head.

[0006] Furthermore, the size of the first through hole is 1.2 mm to 1.4 mm.

[0007] Furthermore, a nail placing and rod pressing device comprises a nail placing device and a rod pressing device, wherein a second through hole penetrating the nail placing device is provided in the axial direction of the nail placing device, a buckle protrusion is provided at one end of the nail placing device, a hexagonal protrusion matching with the hexagonal hole is provided on the surface of the buckle protrusion, and a first grip is provided at the other end of the nail placing device; an outer shell is provided on the surface of the nail placing device, a third through hole matching with the nail placing device is provided in the axial direction of the outer shell, an external thread is provided at one end of the outer shell, and a second grip is provided at the other end of the outer shell; the rod pressing device is a screw plug, a fixing hole is provided in the axial direction of the bolt, and an external thread matching with the internal thread is provided on the surface of the screw plug.

[0008] Furthermore, the guide needle extends out from the end of the nail body after passing through the first through hole, the second through hole and the third through hole respectively.

[0009] In summary, the present invention has the following beneficial effects compared with the prior art:

[0010] Traditional tension screws only have the function of lifting and pressurizing. The hollow tension screw for cervical spine used for surgical treatment provided by the present invention can not only lift and pressurize the two ends of the fracture, but also has a U-shaped nut at the rear and a thread near the nut. After being fixed together with the connecting rod, the injured vertebra and the adjacent vertebral body can be fixed together.

[0011] In the process of drilling the cervical hollow tension screw for surgical treatment provided by the present invention into the cervical vertebra, when the wide thread at the distal end drills into the bone of the fracture end and the narrow thread at the proximal nut has not yet drilled into the bone of the fracture end, when the wide thread in front of the tension screw passes through the distal end of the fracture, the middle part without thread and the proximal fracture end do not have any effect, that is, even if the distal nail head has not drilled in for a while, the part without thread is spinning in place, and the fracture end will not be stretched open because of the thread. When the wide thread at the distal end and the narrow thread at the proximal nut are drilled into the bone of the distal fracture end, the width of the thread is different, which affects the advancement speed of the distal and proximal ends, so that the drilling speed of the wide thread at the distal end is fast, while the drilling speed of the narrow thread at the proximal end is slow, so that the fracture end forms a pressurization effect. In other words, the hollow tension screw for surgical treatment of the cervical vertebra provided by the present invention can achieve the effect of pressurizing the fracture end and fixing it with the adjacent vertebra. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0013] Figure 1 A schematic diagram of the overall structure of a hollow traction screw for cervical vertebrae surgical treatment provided by the present invention;

[0014] Figure 2A side view of a hollow lag screw for cervical vertebrae surgical treatment provided by the present invention;

[0015] Figure 3 It is the cross-sectional view of section AA;

[0016] Figure 4 It is a schematic diagram of the overall structure of a cervical hollow lag screw used for surgical treatment when a screw placement device is used;

[0017] Figure 5 A side view of a cervical hollow lag screw used for surgical treatment when a screw placement device is used;

[0018] Figure 6 It is a cross-sectional view of section BB;

[0019] Figure 7 It is a schematic diagram of the overall structure of a cervical hollow lag screw used for surgical treatment when a pressure rod device is used;

[0020] Figure 8 A side view of a cervical hollow lag screw used for surgical treatment when a pressure rod device is used;

[0021] Fig. 9 It is a cross-sectional view of the CC section.

[0022] The above drawings include the following reference numerals:

[0023] 1. Screw seat; 11. U-shaped groove; 12. Spherical incision; 13. Internal thread; 14. Reset hole; 2. Lag screw; 21. Screw head; 211. Hexagonal hole; 212. Fixing groove; 22. Nail body; 221. Wide thread; 222. Narrow thread; 23. First through hole; 3. Fixing rod; 4. Nail placement device; 41. Second through hole; 42. Buckle protrusion; 43. Hexagonal protrusion; 44. First grip; 5. Shell; 51. Third through hole; 52. External thread; 53. Second grip; 6. Guide pin; 7. Screw plug; 71. Fixing hole. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] See also Figures 1 to 3 As shown, the present invention provides a hollow lag screw for surgical treatment of the cervical vertebra. Similar to the prior art, the hollow lag screw for surgical treatment of the cervical vertebra includes a screw seat 1, a lag screw 2 is sleeved on the lower end of the screw seat 1, a U-shaped groove 11 for accommodating a fixing rod 3 is provided at the upper end of the screw seat 1, the lag screw 2 includes a screw head 21 located at the lower end of the screw seat 1 and a nail body 22 fixedly connected to the lower end of the screw head 21, a spherical incision 12 is provided between the screw head 21 and the screw seat 1 for limiting the screw head 21 from escaping from the lower end of the screw seat 1, an internal thread 13 is provided on the inner wall surface of the screw seat 1, and a reset hole 14 is provided on the side of the surface of the screw seat 1 close to the screw head 21. Different from the prior art, a hexagonal hole 211 is provided in the axial direction of the screw head 21, and a first through hole 23 penetrating the tension screw 2 is provided in the axial direction of the tension screw 2, and the size of the hexagonal hole 211 is larger than the first through hole 23; a wide thread 221 is provided at the end of the surface of the nail body 22 away from the screw head 21, and a narrow thread 222 is provided at the end of the screw head 21 close to the screw head 21, and the pitch of the wide thread 221 is twice that of the narrow thread 222; no thread is provided between the wide thread 221 and the narrow thread 222.

[0027] When in use, the patient's injured vertebra is located through the C-arm, and the orthopedic robot is used to collect data and carry out surgical design and planning; after the robot arm places the working channel, a Kirschner wire guide needle 6 with a diameter of 1.2 mm is drilled into the depth to a distance of about 5 mm from the front edge of the injured vertebra, and the hollow nail is guided by the guide needle 6 to drill into the expanded bone tunnel along the guide needle, and then the hollow nail is replaced with the cervical hollow traction screw for surgical treatment provided by the present invention, and the traction screw 2 is screwed into the affected area to achieve the purpose of pressurizing and fixing the fracture end; finally, the guide needle is removed, and the fixing rod 3 is installed to fix it together with the adjacent vertebra, and fixed by the screw plug 7 to complete the bone grafting fusion operation.

[0028] In addition, during use, after the tension screw 2 is guided to the affected area by the guide needle, the nail placement device 4 is also guided to the corresponding position by the guide needle, and after the outer shell 5 is threadedly connected with the internal thread 13, the hexagonal protrusion 43 on the nail placement device 4 is placed into the hexagonal hole 211 on the screw head 21 and rotated to fix the tension screw 2.

[0029] During the drilling process of the tension screw 2, when the wide thread 221 at the far end has drilled into the bone of the fracture end and the narrow thread 222 near the nut has not yet drilled into the bone of the fracture end, when the wide thread 221 in front of the tension screw 2 passes through the far end of the fracture, the middle part without threads and the near end fracture end do not produce any effect, that is to say, even if the far end nail head has not drilled in for a while, the part without threads is also spinning in place, and the fracture end will not be propped open because of the threads. After the wide thread 221 at the far end and the narrow thread 222 near the nut have both drilled into the bone of the far end fracture end, because the threads at both ends have different pitches (the pitch of the wide thread 221 at the front end is twice that of the narrow thread 222 at the rear end). When the screw is screwed in, because the front and rear ends have different forward speeds (the drilling speed of the wide thread 221 at the far end is fast, and the drilling speed of the narrow thread 222 at the near end is slow), the two fractures can be brought closer to produce a pressurization effect.

[0030] As a preferred embodiment, in order to facilitate the fixing rod 3 to fix the tension screw 2 , a fixing groove 212 corresponding to the U-shaped groove 11 is provided on the screw head 21 .

[0031] As a preference, the guide needle 6 used during the operation is a 1.2 mm Kirschner wire, so the size of the first through hole 23 of the present invention should be between 1.2 mm and 1.4 mm.

[0032] As a preferred embodiment, Figures 4 to 9 As shown, a nail placing and rod pressing device comprises a nail placing device 4 and a rod pressing device, wherein a second through hole 41 penetrating the nail placing device 4 is axially provided on the nail placing device 4, a buckle protrusion 42 is provided at one end of the nail placing device 4, a hexagonal protrusion 43 cooperating with the hexagonal hole 211 is provided on the surface of the buckle protrusion 42, and a first grip 44 is provided at the other end of the nail placing device 4; a shell 5 is provided on the surface of the nail placing device 4, a third through hole 51 cooperating with the nail placing device 4 is axially provided on the shell 5, an external thread 52 is provided at one end of the shell 5, and a second grip 53 is provided at the other end of the shell 5; the rod pressing device is a screw plug 7, a fixing hole 71 is provided axially on the bolt, and an external thread 52 cooperating with the internal thread 13 is provided on the surface of the screw plug 7.

[0033] When in use, the hexagonal protrusion 43 is first inserted into the hexagonal hole 211, the buckle protrusion 42 is locked on the U-shaped groove 11, and then the housing 5 is rotated to make the housing 5 and the screw seat 1 threaded together. At this time, the guide needle 6 can be used to pass through the first through hole 23, the second through hole 41 and the third through hole 51 respectively, and then extend from the end of the nail body 22 to perform cervical spine surgery.

[0034] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0035] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0036] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hollow lag screw for surgical treatment of cervical vertebrae, comprising a screw seat (1), a lag screw (2) being sleeved at the lower end of the screw seat (1), a U-shaped groove (11) being provided at the upper end of the screw seat (1) for accommodating a fixing rod (3), the lag screw (2) comprising a screw head (21) located at the lower end of the screw seat (1) and a nail body (22) fixedly connected to the lower end of the screw head (21), a spherical cutout (12) being provided between the screw head (21) and the screw seat (1) for limiting the screw head (21) from coming out of the lower end of the screw seat (1), an internal thread (13) being provided on the inner wall surface of the screw seat (1), a reset hole (14) being provided on the surface of the screw seat (1) on the side close to the screw head (21), and characterized in that: A hexagonal hole (211) is provided in the axial direction of the screw head (21), and a first through hole (23) penetrating the tension screw (2) is provided in the axial direction of the tension screw (2), and the size of the hexagonal hole (211) is larger than the first through hole (23); a wide thread (221) is provided at one end of the surface of the nail body (22) away from the screw head (21), and a narrow thread (222) is provided at one end of the screw head (21) close to the screw head (21), and the pitch of the wide thread (221) is twice that of the narrow thread (222); no thread is provided between the wide thread (221) and the narrow thread (222).

2. The hollow traction screw for cervical vertebrae for surgical treatment according to claim 1, characterized in that: The screw head (21) is provided with a fixing groove (212) corresponding to the U-shaped groove (11).

3. The hollow traction screw for cervical vertebrae for surgical treatment according to claim 1, characterized in that: The size of the first through hole (23) is 1.2 mm to 1.4 mm.

4. A screw placement and rod pressing device, comprising the hollow lag screw for surgical treatment of cervical vertebrae according to any one of claims 1 to 3, characterized in that: The invention comprises a nail placing device (4) and a screw plug (7), wherein the nail placing device (4) is provided with a second through hole (41) penetrating the nail placing device (4) in the axial direction, and a buckle protrusion (42) is provided at one end of the nail placing device (4), and a hexagonal protrusion (43) matching with the hexagonal hole (211) is provided on the surface of the buckle protrusion (42), and a first grip (44) is provided at the other end of the nail placing device (4); a shell (5) is provided on the surface of the nail placing device (4), and a third through hole (51) matching with the nail placing device (4) is provided in the axial direction of the shell (5), and an external thread (52) is provided at one end of the shell (5), and a second grip (53) is provided at the other end of the shell (5); a fixing hole (71) is provided in the axial direction of the screw plug (7), and an external thread (52) matching with the internal thread (13) is provided on the surface of the screw plug (7).

5. The nail placement and rod pressing device according to claim 4, characterized in that: The guide pin (6) passes through the first through hole (23), the second through hole (41) and the third through hole (51) respectively, and then extends out from the end of the nail body (22).

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