Pedicle cement screw

Abstract

The present application discloses a pedicle cement screw, which comprises a screw body and a connecting arm in axial communication, the connecting arm is used for connecting with a surgical instrument, the screw body comprises a threaded connecting part and a head, at least one overflow hole is arranged on the front end side wall of the threaded connecting part, and the connecting arm and the head are connected in a detachable mode. The pedicle cement screw of the present application is inserted into the interior of a vertebral body, and the front end is connected with a bone cement mass injected in a Kummell cavity, the head is abutted against the rear edge of a pedicle, and plays a limiting role, so as to ensure that the bone cement mass and the pedicle cement screw cannot be displaced, and further ensure the stability. Meanwhile, the connecting arm and the head are connected in a detachable mode, after the operation is completed, the connecting arm is integrally detached, and will not cause stimulation to the surrounding soft tissues, and avoids symptoms such as pain and foreign body sensation caused to the patient.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a pedicle cement screw. BACKGROUND

[0002] With China entering an aging society, osteoporotic vertebral compression fractures, a common disease among the elderly, are gradually increasing. Kummell's disease, or post-traumatic vertebral ischemic necrosis, is a serious complication and end-stage change of osteoporotic vertebral compression fractures.

[0003] For the treatment of Kummell's disease, the traditional surgical method is percutaneous vertebroplasty or percutaneous kyphoplasty, which injects bone cement into the cavity left by Kummell's disease vertebral necrosis. However, because the bone cement is mostly filled in the vertebral fissure, the capsule has been formed in the fissure, and the surrounding vertebral trabeculae are not tightly combined, so the bone cement cannot be firmly anchored to the bone tissue, and it is easy to cause loosening of the bone cement during movement. In severe cases, it can cause displacement and fracture, resulting in further collapse of the vertebral height, and even paraplegia.

[0004] Therefore, it is necessary to design a fixing device that can be used to treat Kummell's disease and ensure the stability of the bone cement mass to prevent it from loosening and shifting, which is still a technical problem to be solved by those skilled in the art. SUMMARY

[0005] The purpose of the present application is to provide a pedicle cement screw that can be used to treat Kummell's disease and ensure the stability of the bone cement mass to prevent it from loosening and shifting.

[0006] To solve the above technical problems, the present application provides a pedicle cement screw, which comprises a nail body and a connecting arm connected in an axial direction, the connecting arm is used to connect with a surgical instrument, the nail body comprises a threaded connection part and a head part, at least one overflow hole is arranged on the front end side wall of the threaded connection part, and the connecting arm and the head part are connected in a detachable manner.

[0007] The procedure for surgical treatment of Kummell's disease using the pedicle cement screw of this invention is as follows: The patient lies prone on the operating table, with a positioning cushion to suspend the injured vertebra and the spine in hyperextension. Fracture reduction is achieved using positioning and manual manipulation. The affected vertebra is located using C-arm fluoroscopy and marked with a line marker. The surgical area is routinely disinfected and draped with sterile sheets. Local anesthesia is administered with 1% lidocaine. The bilateral pedicles of the affected vertebra are located using C-arm fluoroscopy. A longitudinal incision of approximately 0.5 cm is made at each location. A telescoped vertebra is percutaneously inserted through the bilateral pedicles into the vertebral body, approximately 2 mm past the posterior margin of the vertebral body. After confirming good positioning of the vertebrae using C-arm fluoroscopy, the puncture position is adjusted according to the "Kummell cavity" to ensure the vertebral tip is within the "cleft." The vertebral tip is withdrawn, and a syringe is used to aspirate the fluid from the cavity. A guide drill is then inserted sequentially to approximately 3-5 mm from the anterior margin of the vertebral body and withdrawn. If a balloon is used, it can partially open the diseased tissue within the vertebral body. Select one pedicle and place a pedicle cement screw. Insert the screw along the guide pin, ensuring the screw reaches the anterior 1 / 3 of the middle vertebral body, avoiding penetration through the anterior cortex. After attaching the cement inserter, remove the guide pin and set it aside. On the other pedicle, push the cement into the PVP / PKP working sleeve. Under C-arm fluoroscopic monitoring, slowly and in stages inject the cement through the PVP / PKP working sleeve on one pedicle, stopping when the cement fills the vertebral body and approaches the posterior margin. Inject cement along the side of the pedicle screw using the cement inserter, fusing the cement flowing from the screw's tip and side overflow holes with the pre-injected cement to form a single cement mass. After the cement mass solidifies, remove the cement inserter, break the connecting arm, and suture and bandage the incision.

[0008] After surgery, the connecting arm of the pedicle cement screw of this invention is completely detached, while the screw body remains in the patient's body. Specifically, the threaded connecting part is inserted into the vertebral body, and at least from the overflow hole at the rear end to the front end is submerged in the bone cement mass, fixing it to the bone cement mass. The head abuts against the posterior edge of the pedicle, acting as a limit to ensure that the bone cement mass and the pedicle cement screw do not shift, thus ensuring its stability. On the other hand, since the connecting arm is completely detached, it will not irritate the surrounding soft tissues, alleviating the pain, foreign body sensation, and other symptoms caused by existing pedicle cement screws.

[0009] Optionally, the connecting arm and the head are an integral structure, and the sidewall of the connecting arm or the head is provided with a circumferentially extending groove for separating the connecting arm and the head.

[0010] Optionally, the pitch at the rear end of the threaded connection is smaller than the pitch at the front end of the threaded connection.

[0011] Optionally, the rear end of the threaded connection is a double-threaded section, and the front end is a single-threaded section.

[0012] Optionally, there may be multiple overflow holes, which are evenly distributed along the axial direction of the threaded connection.

[0013] Optionally, the overflow hole is an elongated hole with dimensions of 1.5mm × 2mm.

[0014] Optionally, the connecting arm includes a first connecting arm and a second connecting arm disposed opposite to each other, the first connecting arm and the second connecting arm forming a shape that matches the surgical instrument.

[0015] Optionally, the inner walls of the first connecting arm and the second connecting arm are respectively provided with threads for connection with the surgical instrument inserter. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a specific embodiment of the pedicle screw of the present invention;

[0017] Figure 2 for Figure 1 A schematic diagram of the pedicle screw procedure during surgery;

[0018] Figure 3 for Figure 1 A diagram showing the position of the pedicle screw after pedicle bone cement screw surgery;

[0019] in, Figures 1 to 3 The annotations in the attached figures are explained as follows:

[0020] 01-Pedicle; 011-Kummell's disease cavity; 02-Bone cement mass;

[0021] 1-Nail body; 11-Threaded connection part; 11a-Overflow hole; 12-Head; 2-Connecting arm; 21-First connecting arm; 22-Second connecting arm; 2a-Thread; A-Broken groove. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] The terms "first" and "second" used in this article are used only for the convenience of describing two or more structures or components that are identical or similar in structure and / or function, and do not indicate any special limitation on order and / or importance.

[0024] In this article, the end of the threaded connection 11 away from the head 12 is the front end, and the end connected to the head 12 is the rear end.

[0025] Please refer toFigures 1 to 3 , Figure 1 is a structural schematic diagram of a specific embodiment of the pedicle cement screw of the present application; Figure 2 is Figure 1 is a schematic diagram of the pedicle cement screw during the operation; Figure 3 is Figure 1 is a schematic diagram of the position of the pedicle cement screw after the operation is completed.

[0026] The present application provides a pedicle cement screw, which comprises a screw body 1 and a connecting arm 2 in axial communication, the connecting arm 2 is used for connecting with a surgical instrument, the screw body 1 comprises a threaded connection part 11 and a head 12, at least one overflow hole 11a is arranged on the front end side wall of the threaded connection part 11, and the connecting arm 2 and the head 12 are connected in a detachable manner.

[0027] The process of using the pedicle cement screw of the present application to treat Kummell disease is as follows:

[0028] The patient lies prone on the operating table, and the injured vertebra is suspended by a body position cushion, the spine is in hyperextension, and the fracture is reduced by body position and manual method. The lesion vertebra is located by C-arm X-ray machine, and marked with a line pen. The surgical area is routinely disinfected, a sterile towel is laid, and local anesthesia is performed with 1% lidocaine. The lesion vertebra is located by C-arm X-ray machine, and the bilateral pedicles of the lesion vertebra are located. A longitudinal incision about 0.5 cm long is made at the location, a sharp needle with a sleeve is inserted through the bilateral pedicles 01 into the vertebral body, and the needle is inserted about 2 mm beyond the posterior margin of the vertebral body. After the positions of the sharp needles are good under the C-arm X-ray machine, the puncture position is adjusted according to the cavity 011 of Kummell disease during the operation, and the sharp needle is ensured to be located in the “fissure”. The sharp needle is withdrawn, the syringe is connected to withdraw the effusion in the cavity, and the drill is inserted in turn to a distance of about 3-5 mm from the anterior margin of the vertebral body. The drill is pulled out, and if a balloon is used, the balloon can expand the part of the lesion tissue in the vertebral body. A pedicle cement screw is placed in one side of the pedicle 01, and the screw is implanted along the guide needle. The length of the screw reaches the anterior 1 / 3 of the middle part of the vertebral body, and the screw does not penetrate out of the cortex in front of the vertebral body. After the bone cement injector is connected, the guide needle is pulled out and reserved. The bone cement is pushed into the other side of the pedicle 01 through the PVP / PKP working sleeve, and the bone cement is slowly and gradually injected through the PVP / PKP working sleeve of one side of the pedicle under the monitoring of the C-arm X-ray machine. When the bone cement fills the interior of the vertebral body and approaches the posterior margin of the vertebral body, the injection is stopped. The bone cement is injected through the bone cement injector on the side of the pedicle cement screw, and the bone cement flowing out of the front end and side overflow holes 11a of the pedicle screw is fused with the pre-injected bone cement to become a whole bone cement mass 02. After the bone cement mass 02 is solidified, the bone cement injector is removed, the connecting arm is broken, and the incision is sutured and bandaged.

[0029] After the operation of the pedicle bone cement screw of the present application is completed, the connecting arm 2 is removed as a whole, the nail body 1 remains in the patient's body, specifically, the threaded connection part 11 is inserted into the interior of the vertebral body, and at least from the last end overflow hole 11a to the front end part, this part is immersed in the bone cement mass 02, and is fixedly connected with the bone cement mass 02, the head part 12 abuts against the rear edge of the pedicle 01, and plays a limiting role, ensuring that the bone cement mass 02 and the pedicle bone cement screw cannot be displaced, thereby ensuring the stability thereof; on the other hand, since the connecting arm 2 is removed as a whole, it will not cause irritation to the surrounding soft tissues, avoiding symptoms such as pain and foreign body sensation caused to the patient.

[0030] Please continue to refer to Figure 1 In the embodiment, the connecting arm 2 and the head part 12 are a one-piece structure, and the side wall of the connecting arm 2 or the head part 12 is provided with a circumferentially extending break groove A, after the operation is completed, the doctor can break the one-piece structure through the break groove A to remove the connecting arm 2 and leave the head part 12 in the patient's body, preventing the overlong connecting arm 2 from remaining in the body to stimulate the patient's soft tissues and cause corresponding symptoms.

[0031] Of course, in actual application, it is also feasible that the connecting arm 2 and the head part 12 are provided as a split structure and are connected through a detachable manner.

[0032] Further, in the pedicle bone cement screw of the present application, the pitch of the rear end of the threaded connection part 11 is smaller than the pitch of the front end of the threaded connection part 11.

[0033] This arrangement is conducive to enhancing the holding force of the pedicle bone cement screw, and further ensures the positional stability of the bone cement mass 02 and the pedicle bone cement screw, preventing displacement thereof.

[0034] Specifically, in the embodiment, the rear end of the threaded connection part 11 is a double-threaded segment, and the front end is a single-threaded segment.

[0035] Please continue to refer to Figure 1 Figure 1 In the embodiment, the front end side wall of the threaded connection part 11 is provided with three overflow holes 11a, the three overflow holes 11a are uniformly distributed along the axial direction of the threaded connection part 11, the bone cement injected into the pedicle bone cement screw is desirably overflowed through the three overflow holes 11a, and is integrated with the bone cement injected on the opposite side, thereby ensuring the stability of the pedicle bone cement screw.

[0036] Of course, the above-mentioned arrangement of three overflow holes 11a is only exemplary, the number of overflow holes 11a provided on the front end side wall of the threaded connection part 11 can be multiple, as long as it can ensure that the bone cement injected into the pedicle bone cement screw can be desirably overflowed, and integrated with the bone cement injected on the opposite side.

[0037] In addition, the relative positions of the plurality of overflow holes 11a are not limited to being distributed in the axial direction, and can also be distributed in the circumferential direction.

[0038] In this embodiment, the overflow holes 11a are in the shape of long strips, and the size of the overflow holes is 1.5 mm x 2 mm.

[0039] The size of the overflow holes is 1.5 mm x 2 mm, which can ensure that the pedicle screw flows out enough bone cement to fuse with the pre-injected bone cement, and ensure the stability of the bone cement mass; of course, this size is only exemplary, and the size of the overflow holes can be adaptively adjusted on the basis of ensuring the structural strength of the pedicle bone cement screw.

[0040] Further, in this embodiment, the connecting arm 2 includes oppositely arranged first and second connecting arms 21 and 22, and the first and second connecting arms 21 and 22 enclose a shape that matches the surgical instrument.

[0041] This arrangement, while serving the function of connecting the bone cement driver, also makes the connecting arm 2 more easily broken.

[0042] In addition, the inner walls of the first and second connecting arms 21 and 22 are also provided with threads 2a corresponding to the threads, which are used to connect with surgical instruments, such as bone cement drivers, etc.

[0043] The above describes in detail a pedicle bone cement screw provided by the present application, and the principles and implementation modes of the present application are described using specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea. It should be noted that, for those skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A pedicle cement screw, characterized in that, The application relates to a surgical nail, which comprises a nail body (1) and a connecting arm (2) in axial communication, the connecting arm (2) being used for connecting with a surgical instrument, the nail body (1) comprising a threaded connecting portion (11) and a head (12), at least one overflow hole (11a) being arranged on the front end side wall of the threaded connecting portion (11), and the connecting arm (2) and the head (12) being detachably connected. The connecting arm (2) and the head (12) are in an integrated structure, and the side wall of the connecting arm (2) or the head (12) is provided with a circumferentially extending breaking groove (A) for detaching the connecting arm (2) and the head (12); and the head (12) abuts against the rear edge of a pedicle (01).

2. The pedicle bone cement screw of claim 1, wherein, The pitch of the rear end of the threaded connecting portion (11) is smaller than the pitch of the front end of the threaded connecting portion (11).

3. The pedicle bone cement screw of claim 2, wherein, The rear end of the threaded connecting portion (11) is a double-threaded segment, and the front end is a single-threaded segment.

4. Pedicle cement screw according to any of claims 1-3, characterized in that The overflow holes (11a) are long strip holes with a size of 1.5 mm*2 mm.

5. The pedicle bone cement screw according to any one of claims 1-3, characterized in that The connecting arm (2) comprises oppositely arranged first and second connecting arms (21, 22), and the first and second connecting arms (21, 22) enclose a shape matched with the surgical instrument.

6. The pedicle bone cement screw according to any one of claims 1-3, characterized in that Threaded holes (2a) are arranged on the inner side walls of the first and second connecting arms (21, 22) correspondingly, and are used for connecting with the surgical instrument.

7. The pedicle bone cement screw of claim 6, wherein, ​

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