Double-layer tooth ring saw for intervertebral foramen mirror operation

Abstract

The application provides a double-layer tooth ring saw for intervertebral foramen mirror surgery, which comprises an inner layer ring saw module and an outer layer ring saw module, the inner layer ring saw module and the outer layer ring saw module are connected through a clamping component, an elastic reset component, an adjusting component and a connecting component; the inner layer ring saw module comprises an inner layer ring saw and an inner layer ring saw operating handle, the inner layer ring saw operating handle is arranged at the rear end of the inner layer ring saw; the outer layer ring saw module comprises an outer layer ring saw and an outer layer ring saw operating handle, the outer layer ring saw operating handle is arranged at the rear end of the outer layer ring saw, the application mainly utilizes the double-layer tooth ring saw structure, so that the ring cutting efficiency is improved under the premise of ensuring stability, the risk of sliding saw is reduced, and the surgical safety and the surgical efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a double-toothed ring saw for percutaneous endoscopic discectomy. Background Technology

[0002] Lumbar disc herniation is one of the more common degenerative diseases of the spine in clinical practice. Initial episodes of lumbar disc herniation can often be cured with conservative treatment, but patients with recurrent episodes, concurrent lumbar spinal stenosis, or neurological symptoms often require surgical intervention.

[0003] With the development of percutaneous endoscopic lumbar discectomy (PELD), it has gradually become the preferred treatment for lumbar disc herniation. This surgery offers the following advantages: it is performed under local anesthesia, resulting in minimal trauma and preservation of normal lumbar disc function; it requires no muscle dissection or excessive bone removal, minimizing impact on spinal stability; and it allows for rapid recovery and a short hospital stay. One of the key steps in this surgery is the use of a trephine saw to remove the osteophytes distal to the facet joint and part of the superior articular process. The purpose is to widen the intervertebral foramen to provide space for the percutaneous endoscopic procedure, enabling the complete removal of the herniated disc, hypertrophic ligaments, and other nerve-compressing tissues.

[0004] In current percutaneous endoscopic discectomy (PED) procedures, single-layer circumferential saws are often used to remove bone around the intervertebral foramen to enlarge it. However, since the bone around the intervertebral foramen is not a single plane, especially in patients with osteosclerosis, the circumferential saw is prone to slipping off at the bottom of the foramen during circumferential resection (slippage), increasing the risk of nerve injury. Fine-toothed circumferential saws are stable but inefficient, while coarse-toothed circumferential saws are efficient but prone to slippage during operation. Therefore, the currently used single-layer circumferential saw foramen shaping has the problems of unstable circumferential resection and sudden slippage, increasing the risk of nerve injury and making it difficult to meet the requirements of accurate targeted positioning and high circumferential resection efficiency.

[0005] Utility model patent CN211749852U discloses a visual protective ring saw, consisting of two layers fixedly connected together. The outer protective sleeve has an arc-shaped trajectory notch and saw teeth covering the sleeve from the bottom end upwards. During operation, the inner ring saw can rotate while the outer protective sleeve remains fixed, and the saw teeth covering the sleeve protect the proximal nerve tissue. However, in actual spinal endoscopic surgery, a single-layer ring saw design is difficult to balance targeted positioning with circumferential cutting efficiency. When the inner ring saw uses coarse cutting teeth, slippage is likely to occur; when the inner ring saw uses fine cutting teeth, the circumferential cutting efficiency is low during the circumferential cutting process.

[0006] Utility model patent CN212140527U discloses an improved percutaneous endoscopic circumferential saw with depth-limited pressure. It uses a gear and rack to control the depth of the saw's feed, and a limiting groove and spring prevent accidental movement of the adjusting rod, which could damage nerve tissue. This invention offers advantages such as saving surgical time and precise feed, but its complex structure and high manufacturing cost, coupled with the need for constant lubrication due to frequent use of the gear and rack, make it inconvenient for repeated use. Summary of the Invention

[0007] In response to the aforementioned technical problems in conventional percutaneous endoscopic lumbar discectomy (PELD) surgery, such as the risk of slippage when encountering sclerotic bone and the inability to simultaneously achieve good circumferential cutting stability and high efficiency, this invention provides a double-toothed circumferential ...

[0008] The technical means employed in this invention are as follows: A double-toothed trephine saw for percutaneous endoscopic discectomy (PED) is characterized by comprising: an inner trephine saw module and an outer trephine saw module, wherein the inner trephine saw module and the outer trephine saw module are connected by a locking component, an elastic reset component, an adjustment component, and a connecting component; the inner trephine saw module includes an inner trephine saw and an inner trephine saw operating handle, wherein the inner trephine saw operating handle is disposed at the rear end of the inner trephine saw; the outer trephine saw module includes an outer trephine saw and an outer trephine saw operating handle, wherein the outer trephine saw operating handle is disposed at the rear end of the outer trephine saw.

[0009] Furthermore, the inner ring saw operating handle has an inner ring saw groove and an inner ring saw through hole at its center, a circular groove at the connection between the inner ring saw operating handle and the inner ring saw, an inner ring saw countersunk hole at the handle end of the inner ring saw operating handle, and fine cutting teeth at the front end of the inner ring saw; the outer ring saw operating handle has an outer ring saw groove and an outer ring saw through hole at its center, an outer ring saw countersunk hole at the handle end of the outer ring saw operating handle, and coarse cutting teeth at the front end of the outer ring saw.

[0010] Furthermore, the positioning assembly is divided into an upper positioning component and a lower positioning component. The upper positioning component and the lower positioning component have the same structure. The upper positioning component includes an installation end and an adjustment end. The installation end has a positioning component through hole at its center. The positioning component buckle is provided around the through hole to match the inner ring saw groove and the outer ring saw groove. The adjustment section has a positioning component countersunk hole at its center.

[0011] Furthermore, the elastic reset assembly includes an upper retaining member, a reset spring, and a lower retaining member. The upper retaining member is disposed in the circular groove and is a cylindrical boss. The narrow end face of the upper retaining member is provided with an upper retaining member buckle, and the upper end face of the upper retaining member matches the circular groove. The lower retaining member is cylindrical and has a countersunk hole at its center. The side wall of the lower retaining member is provided with a sliding groove that matches the upper retaining member buckle. The lower end of the lower retaining member is provided with a buckle that matches the outer ring saw groove. The reset spring is disposed between the upper retaining member and the lower retaining member.

[0012] Furthermore, the adjustment assembly includes a guide stud, an adjustment bolt, and an adjustment nut; the connecting assembly is a connecting screw; the guide stud has threaded holes at both ends; the guide stud is installed between the inner ring saw countersunk hole and the outer ring saw countersunk hole via the connecting screw; the adjustment nut is disposed between the countersunk holes of the upper and lower locking components via the adjustment bolt.

[0013] Furthermore, the outer side of the adjusting nut is provided with anti-slip texture.

[0014] Compared with the prior art, the present invention has the following advantages: 1. This invention provides a double-toothed ring saw for percutaneous endoscopic discectomy (PED). The double-toothed ring saw design features an inner layer of fine-toothed ring saw and an outer layer of coarse-toothed ring saw. Rotating the adjusting nut allows the inner fine-toothed ring saw to extend a certain distance relative to the outer coarse-toothed ring saw. Under endoscopic guidance, the operator first rotates the inner ring saw a certain distance into the bone layer to ensure stability and prevent slippage. Then, the outer ring saw is rotated to quickly remove bone spurs and articular protrusions, expanding the bone passage. To prevent injury to nerves surrounding the bone tissue, the adjusting nut can be rotated at any time to retract the inner ring saw, eliminating the need to switch between ring saws of different diameters. After the enlargement operation is completed, the double-toothed ring saw can be disassembled by rotating the connector, facilitating subsequent cleaning and disinfection. 2. The present invention provides a double-toothed ring saw for percutaneous endoscopic discectomy, which solves the problems of existing ring saws being prone to ring sawing risks when encountering hardened bone and being unable to balance good ring cutting stability and high efficiency. By designing the inner and outer layers with coarse and fine teeth respectively, it avoids the slippage phenomenon that is prone to occur during the use of traditional single-layer coarse-toothed ring saws, thus improving surgical safety; it also retains the high ring cutting efficiency of coarse-toothed ring saws, thus improving surgical efficiency; at the same time, the double-layered ring saw is detachable, making it convenient for operators to carry and reuse.

[0015] Based on the above reasons, this invention can be widely promoted in fields such as medical device technology. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0018] Figure 2 This is an exploded view of the structure of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0019] Figure 3 This is a schematic diagram of the inner ring saw of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0020] Figure 4 This is a schematic diagram of the outer ring saw of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0021] Figure 5 This is a schematic diagram of the upper locking component structure of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0022] Figure 6 This is a schematic diagram of the upper end clamping structure of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0023] Figure 7 This is a schematic diagram of the lower end clamping structure of a double-toothed ring saw for percutaneous endoscopic discectomy according to the present invention.

[0024] In the diagram: 1. Inner ring saw; 11. Inner ring saw through hole; 12. Inner ring saw groove; 13. Inner ring saw countersunk hole; 14. Circular groove; 15. Fine cutting teeth; 2. Outer ring saw; 21. Outer ring saw through hole; 22. Outer ring saw groove; 23. Outer ring saw countersunk hole; 24. Coarse cutting teeth; 3. Locking assembly; 31. Upper locking component; 311. Locking component through hole; 312. Locking component buckle; 313. Locking component countersunk hole; 32. Lower locking component; 4. Elastic reset assembly; 41. Upper locking component; 411. Upper locking component buckle; 42. Reset spring; 43. Lower locking component; 431. Lower locking component countersunk hole; 432. Slide groove; 5. Adjustment assembly; 51. Guide stud; 52. Adjusting bolt; 53. Adjusting nut; 6. Connecting assembly; 61. Connecting screw. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0028] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0029] In the description of this invention, it should be understood that directional terms such as "front," "back," "up," "down," "left," "right," "lateral," "vertical," "horizontal," and "top," "bottom," etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner or outer contours relative to the outline of each component itself. For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., may be used here to describe the spatial positional relationship between one device or feature and other devices or features as shown in the figures. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if a device in the accompanying drawings is inverted, a device described as "above" or "on top of" other devices or structures will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0030] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0031] like Figure 1 As shown in Figure 7, this invention provides a double-toothed trephine saw for percutaneous endoscopic discectomy, comprising: an inner trephine saw module and an outer trephine saw module. The inner trephine saw module and the outer trephine saw module are connected by a locking component 3, an elastic reset component 4, an adjustment component 5, and a connecting component 6. The inner trephine saw module includes an inner trephine saw 1 and an inner trephine saw operating handle, with the operating handle located at the rear end of the inner trephine saw 1. The outer trephine saw module includes an outer trephine saw 2 and an outer trephine saw operating handle, with the operating handle located at the rear end of the outer trephine saw 2. The inner trephine saw operating handle has an inner trephine saw slot 12 and an inner trephine saw through hole 11 at its center. The inner trephine saw operating handle is connected to the inner trephine saw. The connection of the inner ring saw 1 is provided with a circular groove 14. The handle end of the inner ring saw operating handle is provided with an inner ring saw countersunk hole 13. The front end of the inner ring saw 1 is provided with fine cutting teeth 15. The center of the outer ring saw operating handle is provided with an outer ring saw slot 22 and an outer ring saw through hole 21. The handle end of the outer ring saw operating handle is provided with an outer ring saw countersunk hole 23. The front end of the outer ring saw 2 is provided with coarse cutting teeth 24. The locking component 3 is divided into an upper locking component 31 and a lower locking component 32. The upper locking component 31 and the lower locking component 32 have the same structure. The upper locking component 31 includes an installation end and an adjustment end. The center of the installation end is provided with a locking component through hole 311. The periphery of the locking component through hole 311 is provided with the same as the inner ring saw 15. The inner ring saw groove 12 and the outer ring saw groove 22 are matched by a locking member buckle 312; the center of the adjustment section is provided with a locking member countersunk hole 313; the elastic reset assembly 4 includes an upper locking member 41, a reset spring 42 and a lower locking member 43. The upper locking member 41 is disposed in the circular groove 14. The upper locking member 41 is a cylindrical boss. The narrow end face of the upper locking member 41 is provided with an upper locking member buckle 411. The upper end face of the upper locking member 41 matches the circular groove 14; the lower locking member 43 is cylindrical. The center of the lower locking member 43 is provided with a lower locking member countersunk hole 431. The side wall of the lower locking member 43 is provided with a sliding groove 4 that matches the upper locking member buckle 411. 32. The lower end of the lower end clamp 43 is provided with a buckle that matches the outer ring saw groove 22. The reset spring 42 is disposed between the upper end clamp 41 and the lower end clamp 43. The adjusting component 5 includes a guide stud 51, an adjusting bolt 52 and an adjusting nut 53. The connecting component 6 is a connecting screw 61. The guide stud 51 is provided with threaded holes at both ends. The guide stud 51 is installed between the inner ring saw countersunk hole 13 and the outer ring saw countersunk hole 23 by the connecting screw 61. The adjusting nut 53 is disposed between the upper clamping component 31 and the lower clamping component 32 countersunk hole 313 by the adjusting bolt 52. The outer side of the adjusting nut 53 is provided with anti-slip texture.

[0032] Example 1 like Figure 1 As shown in Figure 7, the present invention discloses a double-toothed ring saw for percutaneous endoscopic discectomy, comprising an inner ring saw 1, an outer ring saw 2, a locking assembly 3, an elastic repositioning assembly 4, an adjusting assembly 5, and a connecting assembly 6. The locking assembly includes an upper locking member 31 and a lower locking member 32. The elastic repositioning assembly includes an upper locking member 41, a repositioning spring 42, and a lower locking member 43. The adjusting assembly includes three guide studs 51, two adjusting bolts 52, and an adjusting nut 53. The connecting assembly includes several connecting screws 61. The present invention allows the inner ring saw to extend a certain distance by rotating the adjusting nut 53, enabling the operator to manipulate and engage the circumferentially cut bone tissue under endoscopic guidance for targeted positioning. When the inner ring saw penetrates a certain distance into the lamina, the outer ring saw contacts the lamina bone tissue, at which point the perforation and circumferential cutting begin. To prevent accidental injury to the central nervous system during the circumferential cutting process, the height adjusting nut is rotated to retract the inner ring saw a certain distance without affecting the operation of the outer ring saw.

[0033] like Figure 3 As shown, one end of the inner ring saw 1 is an operating handle, and a through hole 11 is opened in the center. Several inner ring saw slots 12 are opened around the through hole 11. Each blade of the operating handle is provided with an inner ring saw countersunk hole 13. A circular groove 14 is opened on the lower surface of the center of the inner ring saw 1, and fine cutting teeth 15 are provided around the other end of the inner ring saw 1.

[0034] like Figure 4 As shown, one end of the outer ring saw 2 is an operating handle, and an outer ring saw through hole 21 is opened in the center. Several outer ring saw slots 22 are opened around the outer ring saw through hole 21. Each blade of the operating handle is provided with an outer ring saw countersunk hole 23. Coarse cutting teeth 24 are provided around the lower end of the outer ring saw 2.

[0035] like Figure 1 , 3 As shown in Figure 5, a through hole 311 is formed at the center of one end of the upper locking member 31. Several locking member buckles 312, adapted to the inner ring saw groove 12, are arranged around the bottom of the upper locking member 31 along the through hole 311. The locking member buckles 312 are engaged in the inner ring saw groove 12. A countersunk hole 313 is provided at the other end of the upper locking member 31 for installing the adjusting bolt 52. The lower locking member 32 has the same structure as the upper locking member 31.

[0036] like Figure 2 , 3As shown in Figure 6, the upper end clip 41 is shaped as a cylindrical boss, and a plurality of upper end clip buckles 411 are provided along the circumference of the narrow end face of the upper end clip 41. The size of the upper end face of the upper end clip 41 is adapted to the size of the circular groove 14, and the upper end clip 41 is inserted into the circular groove 14.

[0037] like Figure 2 , 7 As shown, the lower end clamp 43 is cylindrical, with a countersunk hole 431 in the center. Several sliding grooves 432 that are adapted to the upper end clamp buckles 411 are provided around the circumference of the lower end clamp 43. The return spring 42 is placed inside the lower end clamp cylinder, with the bottom end of the spring pressing against the end face of the countersunk hole 431. The upper end clamp 41 is clamped in the sliding grooves 432 by the upper end clamp buckles 411 and pressed against the return spring 42. Several buckles adapted to the outer ring saw grooves 22 are provided around the circumference of the lower end face of the lower end clamp 43, and the buckles are clamped in the outer ring saw grooves 22.

[0038] like Figure 1 , 2 As shown in Figure 5, the guide stud 51 is cylindrical in shape, with threaded holes at both ends. It is threadedly connected to the connecting screw 61 and used to guide the inner ring saw 1. The adjusting bolt 52 is fitted into the countersunk holes of the upper and lower locking members 31 and 32, and is placed within these countersunk holes. The adjusting nut 53 has a threaded through hole between its upper and lower end faces. The adjusting nut 53 is threadedly connected to the adjusting bolt 52, and has anti-slip grooves on its circumference.

[0039] Because bone tissue has a certain rigidity, in order to ensure that the components do not deform during long-term operation, all components except the return spring 42 are made of medical-grade stainless steel.

[0040] Before use, first press the lower end face of the lower end clamp 43 onto the upper end face of the outer ring saw. Then, place the return spring 42 inside the lower end clamp 43. Next, insert the upper end clamp 41 and insert the upper end clamp buckle 411 into the sliding groove 432 of the lower end clamp 43, pressing it onto the return spring 42. Then, insert the inner ring saw 1 and use the guide stud 51 and connecting screw 61 to fix the inner ring saw 1 and the outer ring saw 2. Finally, pass the lower clamping piece 32 through the outer wall of the outer ring saw 2, insert the lower clamping piece buckle 321 into the outer ring saw groove 22, insert the upper clamping piece buckle 311 into the inner ring saw groove 12, and install the adjusting nut 53 and adjusting bolt 52 between the upper clamping piece 31 and the lower clamping piece 32.

[0041] In use, rotate the adjusting nut 53 to extend the inner ring saw 1 a certain distance beyond the outer ring saw 2. Then, under the endoscopic view, the operator performs a circumferential cut on the lamina, engaging the bone tissue for targeted positioning. When the inner ring saw 1 penetrates a certain distance into the lamina, the outer ring saw 2 contacts the lamina bone tissue, initiating a circumferential cut to widen the opening. To prevent accidental injury to the central nervous system during the circumferential cut, rotate the adjusting nut 53 to retract the inner ring saw 1 a certain distance. This does not affect the operation of the outer ring saw 2. After the surgical procedure, remove the ring saw from the cannula. Use other instruments to remove the tissue left after the circumferential cut. The double-layer ring saw can be disassembled by reversing the ring saw installation process, followed by cleaning and disinfection.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A double-toothed ring saw for percutaneous endoscopic discectomy, characterized in that, include: The system comprises an inner ring saw module and an outer ring saw module, connected by a locking component, an elastic reset component, an adjustment component, and a connecting component. The inner ring saw module includes an inner ring saw and an inner ring saw operating handle, with the operating handle positioned at the rear end of the inner ring saw. The outer ring saw module also includes an outer ring saw and an outer ring saw operating handle, with the operating handle positioned at the rear end of the outer ring saw. The inner ring saw has fine cutting teeth at its front end, and the outer ring saw has coarse cutting teeth at its front end. The inner ring saw operating handle has an inner ring saw slot and an inner ring saw through hole at its center, and a circular groove at the connection between the operating handle and the inner ring saw. The handle end of the inner ring saw operating handle has an inner ring saw countersunk hole. The outer ring saw operating handle has an outer ring saw slot and an outer ring saw through hole at its center, and the handle end of the outer ring saw operating handle has an outer ring saw countersunk hole. The locking assembly is divided into an upper locking component and a lower locking component. The upper locking component and the lower locking component have the same structure. The upper locking component includes an installation end and an adjustment end. The installation end has a locking component through hole at its center. The locking component buckle around the through hole matches the inner ring saw groove and the outer ring saw groove. The adjustment end has a locking component countersunk hole at its center. The elastic reset assembly includes an upper retaining member, a reset spring, and a lower retaining member. The upper retaining member is disposed in the circular groove and is a cylindrical boss. The narrow end face of the upper retaining member has an upper retaining member buckle, and the upper end face of the upper retaining member matches the circular groove. The lower retaining member is cylindrical and has a countersunk hole at its center. The side wall of the lower retaining member has a sliding groove that matches the upper retaining member buckle, and the lower end of the lower retaining member has a buckle that matches the outer ring saw groove. The reset spring is disposed between the upper and lower retaining members. The adjustment assembly includes a guide stud, an adjustment bolt, and an adjustment nut. The connecting assembly is a connecting screw. The guide stud has threaded holes at both ends. The guide stud is installed between the inner ring saw countersunk hole and the outer ring saw countersunk hole via the connecting screw. The adjustment nut is set between the countersunk holes of the upper and lower locking parts via the adjustment bolt.

2. The double-toothed ring saw for percutaneous endoscopic discectomy according to claim 1, characterized in that, The adjusting nut has anti-slip texture on its outer side.

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