Personalized customized soft tissue protection device for lumbar surgery under microscope
By designing a personalized lumbar spine surgery protection device, and employing sliding rail and groove technology and expansion fixation components, the problems of existing devices blocking X-rays and inconvenient adjustment have been solved. This allows for flexible adjustment and personalized adaptation, improving surgical efficiency and safety.
Patent Information
- Application Number
- CN202511545395.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-28
- Publication Date
- 2025-12-12
AI Technical Summary
Existing lumbar spine surgery distraction devices are made of metal, which blocks X-rays, require a robotic arm for fixation, are cumbersome to adjust, cannot be customized, and cannot be precisely matched to the patient's soft tissue.
A personalized soft tissue protection device for lumbar spine surgery under a microscope was designed, including a main access body, a tightening closure component, and a spreading and fixing component. It is made of 3D printed photosensitive resin material and expands and contracts through a sliding rail and groove mechanism. It supports manual fine adjustment and can be customized according to the specific condition of the patient. The spreading and fixing component is used to adjust the field of view.
It eliminates the need for robotic arm fixation, allows for flexible position adjustment, reduces complications, improves surgical efficiency, lowers infection risk, adapts to the individualized needs of different patients, and reduces costs.
Smart Images
Figure CN121101769A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical device technology, specifically to a personalized soft tissue protection device for lumbar spine surgery under a microscope. Background Technology
[0002] In recent years, the number of patients with lower back and leg pain has been increasing year by year, seriously affecting people's health. Lumbar disc herniation, lumbar spinal stenosis, lumbar spondylolisthesis, and other degenerative lumbar spine diseases are common causes of lower back and leg pain. Although most cases of lower back and leg pain can be relieved in the early stages with conservative treatments such as medication, physical therapy, and rest, surgical treatment is often necessary if the patient's condition progresses and symptoms such as decreased lower limb muscle strength, cauda equina syndrome, or severe impact on work and daily life occur.
[0003] Lumbar fusion is a commonly used surgical treatment for degenerative lumbar spine diseases. During lumbar spine surgery, the surgeon will separate and expose the soft tissues of the lumbar region along the surgical incision, and then use retractors or retractors to separate the tissues on both sides of the spine to obtain a satisfactory surgical field, making it easier for the surgeon to perform the operation.
[0004] The current lumbar spine surgery distraction device has the following defects: (1) It is made of metal, which can easily block X-rays during the operation; (2) It needs to be connected to a robotic arm for fixation, which is cumbersome and inconvenient; (3) It is inconvenient to adjust after fixation, and it cannot be flexibly swung to adjust the position according to the real-time needs of the operation; (4) It cannot be customized, and it cannot be precisely matched with each patient's soft tissue thickness, lamina width and the range of nerve decompression required. Summary of the Invention
[0005] To address the above problems, this invention provides a personalized soft tissue protection device for lumbar spine surgery under a microscope. It features a simple structure, convenient operation, and eliminates the need for a robotic arm, allowing for flexible position adjustment. The main body of the access tube can contract or expand; when contracted, its inner diameter decreases, facilitating insertion into the patient's body. Expanding the sleeve of the access tube using a stretching fixation device expands the surgical field of view. Different sizes of stretching fixation devices can be selected based on the surgical situation and required field of view, allowing the sleeve to be stretched to the ideal size, facilitating the surgeon's work. This invention can also be personalized to each patient's individual needs, achieving a high degree of adaptation to the patient's physical condition, improving surgical efficiency, and reducing complications and discomfort.
[0006] The present invention is specifically achieved through the following technical solution: a personalized soft tissue protection device for lumbar spine surgery under a microscope, which includes a main channel body, a tightening closure component, and a spreading and fixing component; The main body of the passage includes a sleeve, and the side wall of the sleeve is provided with an opening extending along its axial direction, so that the cross-section of the sleeve is C-shaped. The bottom of the sleeve and the wall on the side opposite to the opening extend along the bottom of the sleeve to form a peak-shaped protrusion. Slide rails extending along the axial direction of the sleeve are symmetrically arranged on the outside of the two side walls of the opening. The tightening closure includes a top cover and a tightening component connected to the lower part of the top cover. The circumferential direction of the tightening component is curved, and its curvature is adapted to the curvature of the sleeve wall. Two sliding grooves I extending axially along the inner side of the tightening component are symmetrically arranged, and the sliding grooves I are adapted to the slide rails on the sleeve. The aforementioned expansion and fixing component includes an outer arc-shaped piece, an inner arc-shaped piece, and an expansion portion connecting the outer and inner arc-shaped pieces. The circumferential curvature of the outer arc-shaped piece, the inner arc-shaped piece, and the expansion portion is adapted to the circumferential curvature of the sleeve. The radial center line of the cross-section of the expansion portion coincides with the radial center line of the outer arc-shaped piece and the radial center line of the inner arc-shaped piece. Moreover, the circumferential width of the expansion portion is smaller than the circumferential width of the outer and inner arc-shaped pieces, so that each side of the expansion and fixing component forms a sliding groove II. The width of the sliding groove II is adapted to the wall thickness on both sides of the sleeve opening. The sliding groove II can be fitted onto the wall surface on both sides of the sleeve opening and slide axially along the sleeve opening.
[0007] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope also has a handle on the outer wall of the sleeve. The handle is positioned opposite the opening, and the angle between the axial extension direction of the handle and the axial extension direction of the opening is greater than 90°.
[0008] Furthermore, the handle is 10-20 cm long and 1-3 cm wide, with the distance between the handle and the top of the sleeve being 0-8 mm.
[0009] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope also has a fixing hole at the upper end of the outer wall of the sleeve. The fixing holes are symmetrically arranged on the left and right sides of the opening, and the inner diameter of the fixing hole is 8-20 mm.
[0010] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope features a rounded transition at the connection between the bottom of the sleeve and the opening, and at the connection between the bottom of the sleeve and the peak-shaped protrusion. The bottom of the peak-shaped protrusion is rounded, and the height h of the peak-shaped protrusion is 3-8 mm.
[0011] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope has a slide rail with an axial length equal to or slightly less than the axial length of the opening, and a circumferential width of the slide rail from the edge of the opening of 3-6 mm.
[0012] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope has a reinforcing rib extending axially along the tightening component between the two slide grooves I. The width of the reinforcing rib is not greater than the distance between the two slide rails after the opening of the sleeve is fully closed. The axial length of the tightening component is greater than the axial length from the top of the opening to the bottom of the opening but less than the axial length from the top of the sleeve to the bottom of the peak-shaped protrusion.
[0013] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope has a radial thickness of 2-5 mm and a circumferential width of 1-12 mm for the spreading part; the spreading and fixing components include multiple components, and the spreading part of each spreading and fixing component has a different circumferential width.
[0014] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope has an axial length of 6-16 cm from the top of the sleeve to the bottom of the peak-shaped protrusion, an inner diameter of 18-25 mm after the sleeve opening is completely closed, and an inner diameter of 19-37 mm after the sleeve is opened by the expansion fixation device.
[0015] The aforementioned personalized soft tissue protection device for lumbar spine surgery under a microscope is made using 3D printing and photosensitive resin.
[0016] Compared with existing technologies, this invention has significant advantages and beneficial effects. Through the above technical solution, this invention achieves considerable technological advancement and practicality, and has broad application value, possessing at least the following advantages: This invention relates to a personalized soft tissue protection device for lumbar spine surgery under a microscope. The device is simple in structure, easy to operate, requires no robotic arm connection, and allows for flexible position adjustment. The sleeve of the access body can be contracted and expanded; when contracted, the inner diameter of the sleeve decreases, facilitating insertion into the patient's body. The access body can be adjusted to the optimal field of view using an operating handle. The sleeve of the access body can be expanded using a sliding rail and groove mechanism, which is convenient, efficient, and accurate, minimizing damage to the patient's soft tissue. Different sizes of the expansion and fixation components can be selected according to the surgical situation and required field of view, allowing the sleeve to be expanded to the ideal size range, facilitating the surgeon's work, effectively protecting the soft tissue at the surgical site, and reducing bleeding. After expansion, the sleeve is fixed using the elasticity of the soft tissue and the interaction force between the sleeve and the soft tissue. It also has a 2-5mm manual operation swing space, providing flexibility during surgery and allowing for manual fine-tuning as needed, resulting in good operability.
[0017] This invention provides a personalized soft tissue protection device for lumbar spine surgery under a microscope. It can be customized to each patient's individual needs, precisely matching the size and location of the herniated disc, as well as the specific condition of the soft tissue and vertebral laminae, based on the patient's MRI and CT scan results. This facilitates the surgeon's work, improves surgical efficiency, and reduces complications and discomfort. Manufactured using 3D printing, each lumbar spine surgery soft tissue protection device takes approximately 1-2 hours to produce, offering convenience and speed without affecting the patient's surgical time. Made with photosensitive resin, it is low-cost, a disposable product, and personalized for each patient, ensuring hygiene and safety and reducing the risk of intraoperative infection. Attached Figure Description
[0018] Figure 1 This is a three-dimensional schematic diagram of the main body of the pathway.
[0019] Figure 2 This is a front view of the main body of the pathway.
[0020] Figure 3 It is a three-dimensional schematic diagram of a tight-fitting closure viewed from below.
[0021] Figure 4 This is a schematic diagram showing the fit between the compression closure and the main body of the passage.
[0022] Figure 5 yes Figure 4 Side view.
[0023] Figure 6 yes Figure 5 A bottom view.
[0024] Figure 7 This is a three-dimensional schematic diagram of the support fixture.
[0025] Figure 8 This is a schematic diagram of the cross-section of the support fixture.
[0026] In the figure, 1-sleeve, 2-opening, 3-handle, 4-fixing hole, 5-peak-shaped protrusion, 6-slide rail, 7-top cover, 8-tightening component, 9-slide groove I, 10-reinforcing rib, 11-outer arc-shaped piece, 12-inner arc-shaped piece, 13-spreading part, 14-slide groove II. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. 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.
[0028] The present invention provides a personalized soft tissue protection device for lumbar spine surgery under a microscope, comprising a main body of the access channel, a tightening closure component, and a spreading and fixing component.
[0029] like Figures 1-2 As shown, the main body of the passage includes a sleeve 1, and the side wall of the sleeve is provided with an opening 2 extending along its axial direction, so that the cross-section of the sleeve is C-shaped. Through this opening, the sleeve can shrink inward under the action of external force to make the inner diameter smaller, or it can expand outward under the action of external force to make the inner diameter larger.
[0030] A handle 3 is provided on the outer wall of the sleeve. The handle is located on the side opposite to the opening, and the angle α between the axial extension direction of the handle and the axial extension direction of the opening is greater than 90°. In one embodiment, the angle α between the axial extension direction of the handle and the axial extension direction of the opening is 90°-150°.
[0031] In one embodiment, the handle is 10-20 cm long and 1-3 cm wide, with the distance between the handle and the sleeve connection point and the top of the sleeve being 0-8 mm. However, this description is not intended to limit the invention, and the dimensions can be adjusted according to actual needs.
[0032] At least two fixing holes 4 are provided at the upper end of the outer wall of the sleeve. The fixing holes are symmetrically arranged on the left and right sides of the opening, and are located between the handle and the opening. The specific shape of the fixing holes is not limited; they can be circular, elliptical, square, rhomboid, pentagonal, hexagonal, octagonal, etc., with an inner diameter of 8-20 mm, a minimum of 8 mm and a maximum of 20 mm. The fixing holes are used in conjunction with existing expanders to facilitate the retraction or expansion of the sleeve.
[0033] The connection between the bottom of the sleeve and the opening is a rounded transition. On the side of the sleeve wall opposite the opening, the bottom extends downwards to form a peak-shaped protrusion 5. The connection between the peak-shaped protrusion and the bottom of the sleeve is a rounded transition, and the bottom of the peak-shaped protrusion is rounded. The height h of the peak-shaped protrusion is 3-8 mm. (See...) Figure 2 As shown, the height h of the peak-shaped protrusion refers to the distance from the bottom of the peak-shaped protrusion to the flat area at the bottom of the sleeve. During surgery, this peak-shaped protrusion is positioned around the lumbar facet joint for fixation.
[0034] In one implementation, the axial length of the sleeve is 6-16 cm, which refers to the distance from the top of the sleeve to the bottom of the peak-shaped protrusion. The axial length of the sleeve varies depending on the distance from the skin to the soft tissue of the lumbar spine at the surgical site, and is therefore individualized. The sleeve used for each patient during surgery needs to be customized.
[0035] Symmetrically arranged on the outer sides of the sleeve opening are slide rails 6 extending axially along the sleeve. The circumferential width of the slide rail from the edge of the opening is 3-6 mm. In one embodiment, the slide rail has an L-shaped cross-section. The axial length of the slide rail is equal to or slightly less than the axial length of the opening.
[0036] like Figure 3 As shown, the tightening closure includes a top cover 7 and a tightening component 8 connected to the lower part of the top cover. The circumferential surface of the tightening component is curved, and its curvature matches the curvature of the sleeve after it is fully closed. Two symmetrically arranged sliding grooves I 9 extending axially along the inner side of the tightening component are provided, and the sliding grooves I match the slide rails on the sleeve. A reinforcing rib 10 extending axially along the tightening component is provided between the two sliding grooves I, and the circumferential width of the reinforcing rib is not greater than the circumferential distance between the two slide rails after the sleeve opening is fully closed.
[0037] When using it, the upper end of the sleeve needs to be manually tightened until the two sides of the sleeve opening fit together. Then, the slide rail is inserted into the slide groove I of the tightening closure component. The L-shaped slide rail and the slide groove I are locked together, so that the sleeve cannot be opened. Then, press the top cover downward along the axis of the tightening closure component, so that the tightening component slides downward along the slide rail axis. During the sliding process, the tightening component gradually closes the opening of the sleeve, so that the inner diameter of the sleeve becomes smaller.
[0038] Preferably, the axial length of the compression member is slightly greater than the axial length from the top of the opening to the bottom of the opening, but less than the axial length from the top of the sleeve to the bottom of the peak protrusion.
[0039] The aforementioned expansion and fixing component includes an outer arc-shaped piece 11, an inner arc-shaped piece 12, and an expansion portion 13 connecting the outer and inner arc-shaped pieces. The circumferential curvature of the outer arc-shaped piece, the inner arc-shaped piece, and the expansion portion is adapted to the circumferential curvature of the sleeve. The radial thickness of the expansion portion is 2-5 mm, and its circumferential width is 1-12 mm. The radial centerline of the cross-section of the expansion portion coincides with the radial centerline of the outer arc-shaped piece and the radial centerline of the inner arc-shaped piece, and the circumferential width of the expansion portion is less than the circumferential width of the outer and inner arc-shaped pieces, so that each side of the expansion and fixing component forms a sliding groove structure, defined as sliding groove II 14. The width of sliding groove II (i.e., the radial thickness of the expansion portion) is not less than the wall thickness of the two side walls at the opening of the sleeve.
[0040] The expansion fasteners include multiple components, each with a different circumferential width, resulting in different inner diameters after the sleeve is expanded.
[0041] Furthermore, the circumferential width of the expansion portion is not limited to 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, or 12 mm, and the above description is not considered a limitation of the present invention. The circumferential width dimension of the expansion portion is marked on each expansion fastener for easy identification and use.
[0042] Preferably, the initial inner diameter of the sleeve after the opening is completely closed is 18-25 mm, and the initial inner diameter of the sleeve is determined according to the size of the intervertebral disc herniation and the range of decompression required for different patients. The inner diameter of the sleeve after being opened using different sized expansion and fixation members is 19-37 mm. The above description is not to be regarded as a limitation of the present invention.
[0043] The method of using the personalized soft tissue protection device for lumbar spine surgery under a microscope as described in this invention includes: (1) Place a soft tissue protection device for lumbar spine surgery at the skin incision site. First, manually tighten the upper end of the sleeve of the main body of the passage until the two sides of the sleeve opening fit together. Then, put the lower end of the groove of the tightening closure part on the upper end of the two slide rails of the sleeve. Press the top cover down along the axial direction of the tightening closure part so that the tightening part slides down along the axial direction of the sleeve slide rail until the bottom of the top cover fits with the top of the sleeve, so that the two sides of the sleeve opening are completely contracted and fitted together. After the sleeve contracts, the inner diameter becomes smaller.
[0044] (2) Slowly insert the retracted sleeve into the patient’s body through the surgical incision until the peak-shaped protrusion at the bottom of the sleeve is stuck around the intervertebral joint (lumbar facet joint) to be operated on, so that the intervertebral joint is located in the sleeve passage. With the assistance of a medical microscope for spinal surgery, slowly adjust the sleeve to the optimal surgical position so that the intervertebral joint is visible in the sleeve passage. Then slowly slide the tightening closure out of the patient’s body and remove it.
[0045] (3) Using a conventional surgical retractor, the two hooks of the retractor are hooked into the fixing holes on both sides of the sleeve opening. The retractor is pulled in opposite directions to widen the sleeve opening. While widening the sleeve opening, the retractor part with a suitable circumferential width is inserted into the opening from the top. The sleeve walls on both sides of the opening are fitted into the sliding grooves II on both sides of the retractor. The sleeve walls on both sides of the opening act like slide rails. Using surgical forceps, surgical scissors, or other surgical tools, the retractor is pushed downward along the sleeve opening axis to slide downward. When the retractor slides to the middle or lower-middle part of the opening axis, the sleeve opening is fully opened. At this time, the inner diameter of the sleeve increases, and the intervertebral joint at the bottom of the sleeve passage is clearly visible. Subsequently, the doctor performs the corresponding surgical work. During the operation, assistant doctors or nurses can help fix the handle to further ensure the stability of the sleeve position during the operation.
[0046] (4) After the surgery is completed, the main body of the access passage is slowly removed.
[0047] All the above operations were performed in a sterile environment. The soft tissue protection device for lumbar spine surgery was sterilized before use. This is a routine medical operation for those skilled in the art and will not be described in detail here.
[0048] This invention relates to a personalized soft tissue protection device for lumbar spine surgery under a microscope. The device is a customized product, with the axial length of the sleeve, the inner diameter of the sleeve opening after complete closure (initial inner diameter), and the required surgical passage inner diameter (i.e., the inner diameter of the sleeve opening after it is expanded) determined based on each patient's physical condition. The distance between the two grooves I on the tightening closure needs to match the distance and size of the two slide rails on the sleeve, and the axial length of the tightening closure is adaptively adjusted according to the axial length of the sleeve. The main passage and tightening closure need to be customized for each patient. If the wall thickness on both sides of the sleeve opening remains constant, the expansion and fixing component can be made into a standardized, off-the-shelf part so that it can be used with the customized passage body for each patient.
[0049] The personalized soft tissue protection device for lumbar spine surgery under a microscope of the present invention can be manufactured by 3D printing. It takes about 1-2 hours to manufacture a set of this lumbar spine surgery soft tissue protection device by 3D printing, which will not delay the patient's surgery. Each personalized customization only requires simple adjustment of the axial length of the sleeve, the inner diameter of the sleeve after the opening is fully closed (initial inner diameter), and the distance between the two sliding grooves I on the tightening closure part (in some cases, the circumferential width of the reinforcing rib may need to be adjusted).
[0050] When using 3D printing to fabricate the soft tissue protection device for lumbar spine surgery, the material used is photosensitive resin, such as the BFOR001 photosensitive resin produced by a medical technology company in Shanghai. It is mainly composed of alicyclic epoxy resin, epoxy diluent, photoinitiator, photostarter, etc.
[0051] It should be noted that the personalized soft tissue protection device for lumbar spine surgery under a microscope of the present invention is a single-use product and cannot be reused after each patient's use. The main body of the access channel, the tightening closure component, and the opening and fixing component are all single-use products.
[0052] The above description is merely an embodiment of the present invention and is not intended to limit the present invention in any way. The present invention can also have other embodiments based on the above structure and function, which will not be listed hereafter. Therefore, any simple modifications, equivalent changes, and alterations made by those skilled in the art to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A personalized soft tissue protection device for lumbar spine surgery under a microscope, characterized in that... Includes the main body of the passage, the tightening closure, and the expanding and fixing components; The main body of the passage includes a sleeve (1), and the side wall of the sleeve is provided with an opening (2) extending along its axial direction, so that the cross-section of the sleeve is C-shaped. The bottom of the sleeve and the wall on the opposite side of the opening extend along the bottom of the sleeve to form a peak-shaped protrusion (5). The outer sides of the two walls of the opening are symmetrically provided with slide rails (6) extending along the axial direction of the sleeve. The tightening closure includes a top cover (7) and a tightening component (8) connected to the lower part of the top cover. The circumferential direction of the tightening component is curved, and its curvature is adapted to the curvature of the sleeve wall. Two sliding grooves I (9) extending axially along the tightening component are symmetrically arranged on the inner side of the tightening component. The sliding grooves I are adapted to the sliding rails (6) on the sleeve. The aforementioned expansion and fixing member includes an outer arc-shaped piece (11), an inner arc-shaped piece (12), and an expansion part (13) connecting the outer arc-shaped piece and the inner arc-shaped piece. The circumferential curvature of the outer arc-shaped piece, the inner arc-shaped piece, and the expansion part is adapted to the circumferential curvature of the sleeve. The two sides of the expansion and fixing member are provided with sliding grooves II (14) extending axially along the expansion and fixing member. The sliding grooves II can be fitted onto the wall surfaces on both sides of the sleeve opening and slide axially along the sleeve opening.
2. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... A handle (3) is also provided on the outer wall of the sleeve. The handle is positioned opposite to the opening, and the angle between the axial extension direction of the handle and the axial extension direction of the opening is greater than 90°.
3. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 2, characterized in that... The handle is 10-20 cm long and 1-3 cm wide, with the distance between the handle and the top of the sleeve being 0-8 mm.
4. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1 or 2, characterized in that... A fixing hole (4) is also provided at the upper end of the outer wall of the sleeve. The fixing holes are symmetrically arranged on the left and right sides of the opening.
5. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... The connection between the bottom of the sleeve and the opening, and the connection between the bottom of the sleeve and the peak-shaped protrusion, are all rounded. The bottom of the peak-shaped protrusion is rounded.
6. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... The axial length of the slide rail is equal to or slightly less than the axial length of the opening, and the circumferential width of the slide rail from the edge of the opening is 3-6 mm.
7. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... A reinforcing rib (10) extending axially along the tightening component is provided between the two sliding grooves I. The axial length of the tightening component is greater than the axial length from the top of the opening to the bottom of the opening and less than the axial length from the top of the sleeve to the bottom of the peak protrusion.
8. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... The radial thickness of the expansion part is 2-5 mm, and its circumferential width is 1-12 mm; the expansion fasteners include multiple parts, and the expansion part of each expansion fastener has a different circumferential width.
9. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1 or 8, characterized in that... The axial length from the top of the sleeve to the bottom of the peak-shaped protrusion is 6-16 cm, the inner diameter of the sleeve after the opening is completely closed is 18-25 mm, and the inner diameter of the sleeve after it is opened by the expansion fastener is 19-37 mm.
10. The personalized soft tissue protection device for lumbar spine surgery under a microscope as described in claim 1, characterized in that... It is made using 3D printing, and the material used is photosensitive resin.