Vertebral pedicle osteotomy extension screw

Abstract

The utility model relates to the technical field of medical instruments, and discloses a pedicle osteotomy extension screw which comprises an outer sleeve screw and an inner fixing screw, the outer sleeve screw is provided with internal and external threads, the threads in the outer sleeve screw are designed to be of a double-thread structure, the inner fixing screw is provided with a double-external-thread structure, and the double-external-thread structure is designed to be of a double-external-thread structure. The double-external-thread structure is in threaded connection with the internal double threads of the outer sleeve nail, the length of the outer sleeve nail is 20 mm, the bottom diameter of the external threads is 10 mm, and the front end of the outer sleeve nail is 5 mm without threads. According to the vertebral pedicle osteotomy extension screw, the front vertebral body and the rear accessory of the lumbar vertebra which are disconnected from the vertebral pedicle and close to each other can be rapidly expanded in opposite directions by screwing in the outer sleeve screw in the operation, the expanding height can be conveniently adjusted, so that the oppression of the oppressed nerve is relieved, and the backward moving direction of the accessory is not limited in the expanding process of the outer sleeve screw; the inner sleeve nail can be screwed into the vertebral body through the outer sleeve nail after the outer sleeve nail is matched with the zygopophysis of the adjacent section, the front-back structure of the lumbar vertebra is locked, and vertebral pedicle reconstruction is completed.

Description

Technical Field

[0001] The utility model relates to the technical field of medical instruments, in particular to a pedicle osteotomy extension screw. Background Art

[0002] Diseases such as lumbar disc herniation, spinal stenosis, lumbar spondylolisthesis, and degenerative lumbar scoliosis are often accompanied by extreme narrowing of the intervertebral space on one or both sides. During the treatment process, the narrow spinal canal needs to be enlarged and the intervertebral foramen needs to be expanded to relieve the compression of the dura mater and nerve roots and cure the disease.

[0003] At present, the traditional method of pedicle distraction is often to use screw distraction, which is achieved by implanting screws into the pedicle body to distract the pedicle;

[0004] Among them, it was found through searching that the patent with application number CN200910174975.5 discloses a pedicle lengthening device, including a front nail, a core rod, a rear nail and a fixator, wherein the core rod is a hollow structure, a communicating through hole is provided in the middle thereof, a front end of the core rod is threadedly connected with the front nail, a rear end of the core rod is sleeved with the rear nail, and the core rod is slidably connected with the rear nail; the fixator is fixedly connected to the rear end of the rear nail, and the core rod and the rear nail are relatively fixed;

[0005] The pedicle extension device in the above patent document can separate the vertebral body and pedicle through the front screw, core rod, rear screw and fixator, extend the distance between the two, and finally achieve the purpose of expanding the spinal canal and intervertebral foramen and decompressing. It can be used for surgical treatment of lumbar spinal stenosis and has good application prospects. However, the length and direction of the screw are fixed, and the height and direction of the pedicle expansion cannot be adjusted after implantation. Therefore, a pedicle osteotomy extension screw is urgently needed to solve the above problem. Utility Model Content

[0006] 1. Technical issues to be solved

[0007] In view of the deficiencies in the prior art, the utility model provides a pedicle osteotomy extension screw, which has the advantages of easy adjustment of the distraction height and direction, and solves the problem that the length and direction of the traditional screw are fixed and the pedicle distraction height and direction cannot be adjusted after implantation.

[0008] (II) Technical solution

[0009] The utility model solves the above-mentioned technical problem with the following technical solution: a pedicle osteotomy extension screw, comprising an outer sleeve nail and an inner fixing nail, the outer sleeve nail is provided with inner and outer threads, the inner threads of the outer sleeve nail are designed as a double thread structure, the inner fixing nail is provided with a double outer thread structure, and the double outer thread structure is threadedly connected to the inner double threads of the outer sleeve nail, and the inner fixing nail is placed inside the outer sleeve nail when in use.

[0010] The beneficial effects of the utility model are:

[0011] The pedicle osteotomy extension screw can quickly distract the anterior vertebral body and posterior attachments of the lumbar spine that have been disconnected from the pedicle and moved close to each other in opposite directions by screwing in the outer sheath screw during the operation, so as to facilitate adjustment of the distraction height and relieve compression of the compressed nerves and alleviate the patient's symptoms. During the distraction process of the outer sheath screw, the posterior movement direction of the attachment is not restricted and can adapt to the articular processes of the adjacent segments. Then, the internal fixation screw is screwed into the vertebral body through the outer sheath screw to lock the anterior and posterior structures of the lumbar spine and complete the pedicle reconstruction.

[0012] On the basis of the above technical solution, the present invention can also be improved as follows.

[0013] Furthermore, the outer sleeve nail is 20 mm long, the outer thread bottom diameter is 10 mm, the front end 5 mm is unthreaded, and the tail adopts a hexagonal structure design.

[0014] Furthermore, the length of the internal fixing nail is 30 mm, and the tail portion adopts an internal hexagonal structure design, and its outer diameter is larger than the diameter of the external thread structure of the internal fixing nail. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the utility model;

[0016] Figure 2 This is a cross-sectional view of the structure of the utility model;

[0017] In the figure: 1. Internal fixation nail; 2. Outer nail. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] In the embodiment, Figure 1 , 2 is given, a pedicle osteotomy extension screw, the utility model comprises an outer sleeve nail 2 and an inner fixation nail 1, the outer sleeve nail 2 is an inner and outer double thread structure, the length is 20mm, the outer thread bottom diameter is 10mm, the front end 5mm is unthreaded, and the tail adopts an inner hexagonal structure design.

[0020] The inner thread of the outer sleeve nail 2 is designed as a double thread structure, and the inner fixing nail 1 is a double outer thread structure, and the double outer thread structure is threadedly connected to the inner double thread of the outer sleeve nail 2. When in use, the inner fixing nail 1 is placed inside the outer sleeve nail 2. The inner fixing nail 1 is 30 mm long, and the tail also adopts an inner hexagonal structure design, and its outer diameter is slightly larger than the diameter of the outer thread structure of the inner fixing nail 1.

[0021] The internal fixation nail 1 is hollow in design and can be implanted percutaneously into the outer sleeve nail 2 under the guidance of a guide wire. Multiple side openings are arranged on the side of the nail head. After implantation, bone cement can be implanted into the vertebral body in conjunction with a bone cement push rod to enhance the holding force of the internal fixation nail 1 on the vertebral cancellous bone. The internal fixation nail 1 is placed inside the outer sleeve nail 2 when in use.

[0022] It should be noted that both the outer sleeve nail 2 and the internal fixation nail 1 use the cancellous bone thread of a conventional pedicle screw. The outer thread of the outer sleeve nail 2 can also use the cortical bone thread. During the operation, the outer sleeve nail 2 is connected to the external screw implantation instrument through the hexagonal structure at the tail, so as to realize the implantation of the outer sleeve nail 2 into the pedicle of the osteotomy.

[0023] The design of the 5mm non-threaded structure at the front end of the outer sheath nail 2 facilitates the implantation of the screw and reduces the damage to the vertebrae and nerve roots by the front end of the screw. During the operation, the internal fixation nail 1 is also implanted into the outer sheath nail 2 through the internal hexagonal structure at the tail and the external instrument structure, and the internal fixation nail 1 is implanted into the vertebral body below the outer sheath nail 2 through the cooperation of the internal and external double thread structures.

[0024] When the height of the upper and lower pedicles needs to be adjusted during the operation, the outer sleeve screw 2 is rotated to move toward the vertebral body, pushing the vertebral body and the rear attachment to move in the opposite direction, thereby extending the pedicles and expanding the spinal canal, thereby decompressing the compressed nerves, alleviating the patient's pain, facilitating the operator's further operation, and improving the treatment effect and efficiency.

[0025] By providing this type of extension screw and using it in conjunction with the pedicle extension device, the pedicle extension device becomes the main fulcrum after insertion, and after the extension screw is inserted, it serves as a secondary fulcrum to carry out targeted expansion of the compression point, so that the compression point of the nerve can be adjusted more accurately. At the same time, compared with the complete insertion of multiple pedicle extension devices, the cost is reduced.

[0026] Working principle:

[0027] During the operation, the outer sheath nail 2 cooperates with the front end of the internal fixation nail 1 through the hexagonal structure at the tail end, and is connected to the tail end of the instrument through an external screw implantation device, so that the outer sheath nail 2 can be implanted into the pedicle of the osteotomy. The internal fixation nail 1 is implanted into the outer sheath nail 2 and implanted into the vertebral body below the outer sheath nail 2 through the cooperation of the internal and external double thread structures. When the length of the pedicle needs to be adjusted during the operation, the outer sheath nail 2 is rotated forward to achieve relative movement of the vertebral body and the rear accessories in opposite directions, thereby extending the pedicle, thereby decompressing the compressed nerves and alleviating the patient's pain. During the process of expanding the outer sheath nail 2, the posterior movement direction of the accessories is not restricted, and after adapting to the articular process of the adjacent segment, the internal fixation nail 1 is screwed into the vertebral body through the outer sheath nail 2 to lock the anterior and posterior structures of the lumbar vertebra and complete the pedicle reconstruction.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pedicle osteotomy extension screw, comprising an outer screw (2) and an inner fixation screw (1), characterized in that: The outer sleeve nail (2) is provided with internal and external threads, the internal threads of the outer sleeve nail (2) are designed as a double thread structure, the inner fixing nail (1) is provided with a double external thread structure, and the double external thread structure is threadedly connected with the internal double threads of the outer sleeve nail (2), and the inner fixing nail (1) is placed inside the outer sleeve nail (2) when in use.

2. The pedicle osteotomy and extension screw according to claim 1, characterized in that: The outer sleeve nail (2) has a length of 15-35 mm, an outer thread bottom diameter of 8-14 mm, a front end of 5-10 mm without thread, and a hexagonal structure design at the tail.

3. The pedicle osteotomy and lengthening screw according to claim 1, characterized in that: The inner fixing nail (1) is 30-70 mm long, and the tail portion is designed with an inner hexagonal structure, the outer diameter of which is larger than the diameter of the outer thread structure of the inner fixing nail (1).

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