Minimally invasive ultrasonic guided percutaneous rabbit intervertebral disc degeneration modeling mode

Abstract

The invention discloses a minimally invasive ultrasonic guided percutaneous rabbit intervertebral disc degeneration modeling mode, and relates to the technical field of ultrasonic modeling, and the method comprises the following steps: fixing an experimental rabbit on an operation table in a prostrate manner in an anesthetic state, and raising the abdomen to maintain lumbar lordosis; an ultrasonic probe is used for scanning along the longitudinal axis of the spine, and the L5 transverse process is recognized upwards from the highest point of the crista iliaca; positioning an L5 / 6 intervertebral disc gap in the cross section ultrasonic image by taking the identified L5 transverse process as an anatomical reference; a stable high-echo target spot formed by fascia is confirmed in the intersection area of the L5 transverse process head side and the superior articular process ventral side; marking a puncture needle insertion position on the skin surface according to the high-echo target spot; percutaneous puncture is conducted under ultrasonic real-time guidance along the marked position, the needle tip slides into the L5 / 6 intervertebral disc along the superior zygopophysis bone surface, and it is confirmed that the needle tip is located in the nucleus pulposus through viscous resistance and the unlocking hand feeling; the needle tip is controlled to stay in the intervertebral disc for 10 seconds, the puncture depth is kept at 5 mm, and mechanical disturbance is completed to induce the intervertebral disc to retreat.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic modeling technology, and in particular to a minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method. Background Technology

[0002] Ultrasonic modeling technology refers to a set of animal model construction methods that use high-frequency ultrasound imaging as the only intraoperative guidance method to achieve precise and safe entry of percutaneous needles into the rabbit lumbar intervertebral disc by identifying specific ultrasound anatomical landmarks (such as the L5 transverse process and fascial hyperechoic target points) without the need for X-ray or CT assistance, and induce intervertebral disc degeneration through controlled mechanical disturbance.

[0003] Current percutaneous puncture modeling methods generally use C-arm X-ray machines for intraoperative guidance, requiring repeated fluoroscopy to confirm the puncture needle position. This process not only exposes the experimental animals to unnecessary radiation but also poses cumulative radiation hazards to the operators, potentially increasing long-term health risks such as cancer and reproductive damage. Furthermore, X-rays can only display bony outlines and cannot distinguish key soft tissues such as the spinal canal, nerve roots, dural sac, and surrounding blood vessels. During the puncture process, positioning errors can easily lead to the needle tip accidentally entering the spinal canal or damaging nerve roots, causing serious complications such as hind limb paralysis and motor dysfunction in experimental rabbits, directly affecting the effectiveness of the model and animal welfare. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides a minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration model, addressing the shortcomings of existing percutaneous puncture models that commonly rely on C-arm X-ray guidance and require repeated fluoroscopy to confirm needle placement. This process not only exposes the animals to unnecessary radiation but also poses cumulative radiation hazards to operators, potentially increasing long-term health risks such as cancer and reproductive damage. Furthermore, X-rays only reveal bony outlines and cannot distinguish crucial soft tissues like the spinal canal, nerve roots, dural sac, and surrounding blood vessels. During puncture, positioning errors can easily lead to needle tip entry into the spinal canal or nerve root damage, causing serious complications such as hind limb paralysis and motor dysfunction in the rabbits, directly impacting the model's effectiveness and animal welfare.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method, comprising: The experimental rabbits were placed in a prone position on the operating table under anesthesia, with their abdomens elevated to maintain lumbar lordosis. Using an ultrasound probe, scan along the longitudinal axis of the spine to identify the L5 transverse process from the highest point of the iliac crest upwards; Using the identified L5 transverse process as an anatomical reference, the L5 / 6 intervertebral disc space was located in the transverse ultrasound image; Confirm a stable, hyperechoic target point formed by fascia in the area where the head side of the L5 transverse process and the ventral side of the superior articular process meet. Mark the puncture and needle insertion points on the skin surface based on the hyperechoic target points; Under real-time ultrasound guidance, the needle tip was punctured along the marked location and slid into the L5 / 6 intervertebral disc along the superior articular process bone surface. The needle tip was confirmed to be in the nucleus pulposus by viscous resistance and unlocking-like tactile sensation. The needle tip is held within the intervertebral disc for 10 seconds while maintaining a puncture depth of 5 mm to induce mechanical disturbance and induce disc retraction.

[0007] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the specific steps of fixing the experimental rabbit in a prone position on the operating table under anesthesia with the abdomen elevated to maintain lumbar lordosis are as follows: The experimental rabbits were given general anesthesia; After the experimental rabbits entered a stable state of anesthesia, they were placed on the operating table in a prone position. Secure the limbs to the four corners of the operating table; Place a support pad under the abdomen to allow the lumbar spine area to stretch naturally and be fully exposed.

[0008] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the specific steps of using an ultrasound probe to scan along the longitudinal axis of the spine and identifying the L5 transverse process upwards from the highest point of the iliac crest are as follows: Start the ultrasound equipment and connect the convex array probe; The convex array probe was placed on the skin surface of the lumbosacral region on the tail side of the experimental rabbit; Slowly move the probe along the midline of the spine toward the head to perform a longitudinal section scan; To observe changes in bony echogenic structures, first identify the transverse process corresponding to the highest point of the iliac crest; Continuing the scan towards the head, the clearly defined and isolated superior transverse process was identified as the L5 transverse process.

[0009] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the specific steps for locating the L5 / 6 intervertebral disc space in the transverse ultrasound image, using the identified L5 transverse process as the anatomical reference, are as follows: Keep the probe position stable in the L5 transverse process area; Rotate the probe 90 degrees to change the longitudinal section to the transverse section; Adjust the probe angle to make the L5 transverse protrusion appear as a transverse high-echo strip structure; Observe the adjacent area on the inner side of the L5 transverse process to identify a well-defined, elliptical hypoechoic area; The hypoechoic area is the location of the L5 / 6 intervertebral disc space.

[0010] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the specific steps for confirming the stable hyperechoic target point formed by the fascia in the intersection area of ​​the L5 transverse process head side and the superior articular process ventral side are as follows: In the cross-sectional image, locate the region above and outside the head of the L5 transverse process; Identify a point-like structure within the area with sharp boundaries and an echo intensity higher than the surrounding soft tissue; Among them, the hyperechoic structure is located at the junction of the ventral side of the superior articular process and the transverse process; The hyperechoic structure was confirmed to be stable in position and consistent in shape during multiple scans, and was used as the ultrasound-guided target for the puncture path.

[0011] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the specific steps of marking the puncture needle insertion position on the skin surface based on the hyperechoic target point are as follows: Keep the probe position unchanged to ensure that the high-echo target is clearly displayed in the center of the screen; Draw a straight line on the skin surface along the long axis of the probe with a marker; Move a certain distance outward along this straight line and mark a point on the body surface as the needle insertion point; After marking, remove the probe, leaving the surface markings for subsequent puncture procedures.

[0012] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the following steps are taken: Percutaneous puncture is performed along the marked location under real-time ultrasound guidance, allowing the needle tip to slide along the superior articular process surface into the L5 / 6 intervertebral disc. The location of the needle tip in the nucleus pulposus is confirmed by viscous resistance and a "locking"-like tactile sensation. Place the puncture needle at the marked insertion point; Reposition the ultrasound probe so that the puncture path coincides with the sound beam plane; The puncture needle was slowly advanced under real-time ultrasound monitoring. When the needle tip touches the bone of the superior articular process, a strong echoic bright spot with acoustic shadowing is observed; Fine-tune the puncture angle so that the needle tip slides along the bone surface toward the intervertebral disc; When the needle tip passes through the annulus fibrosus and enters the nucleus pulposus, the operator feels a significant change in resistance and a slight unlocking sensation; Meanwhile, ultrasound images showed that the needle tip had entered the hypoechoic intervertebral disc region.

[0013] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the control needle tip remains in the intervertebral disc for 10 seconds while maintaining a puncture depth of 5 mm to complete mechanical disturbance and induce intervertebral disc degeneration. The specific steps are as follows: Once the needle tip is confirmed to be inside the intervertebral disc, continue needle insertion. Maintain the needle position stable and do not perform rotation or aspiration actions; Start the timer and keep the needle tip still inside the intervertebral disc; During the resting period, continuously observe the ultrasound images to ensure that the needle tip has not shifted; After the preset time has elapsed, slowly withdraw the puncture needle.

[0014] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the following steps are taken after the modeling is completed: anteroposterior and lateral X-ray images of the lumbar spine are taken on the experimental rabbits to verify that the puncture needle tract did not enter the spinal canal and did not cause vertebral fracture or facet joint damage. The success of the model is then comprehensively determined by combining the results of magnetic resonance imaging and histological staining at different postoperative time points. The specific steps are as follows: After the puncture procedure, the experimental rabbit was transferred to the X-ray examination platform; Take anteroposterior and lateral X-ray films of the lumbar spine; Two or more people independently reviewed the images to confirm that there was no pedicle destruction, no foreign body in the spinal canal, and no facet fracture. Magnetic resonance scanning was performed on the experimental rabbits at multiple time points after the operation. After the scan was completed, the animal was euthanized and L5 / 6 intervertebral disc tissue was taken. The tissue samples were then fixed, dehydrated, embedded, and sectioned in sequence. Immunohistochemical staining for type II collagen, Masson's trichrome staining, and Safranin O staining were performed respectively. The integrity of the annulus fibrosus structure, the density of nucleus pulposus cells, and the changes in proteoglycan content were observed under a microscope.

[0015] As a preferred embodiment of the minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method described in this invention, the entire operation process does not require X-ray fluoroscopy assistance, and relies entirely on real-time ultrasound imaging to visualize the puncture path, effectively avoiding the potential harm of ionizing radiation to experimental personnel and animals. At the same time, through the ability of ultrasound to distinguish between soft tissue and bony interfaces, it avoids the puncture needle from accidentally entering the spinal canal or damaging nerve roots, thereby preventing serious complications such as lower limb paralysis in experimental rabbits and ensuring the reproducibility and biological effectiveness of the degeneration model.

[0016] The beneficial effects of this invention are as follows: By establishing an ultrasound anatomical positioning system centered on the L5 transverse process and the hyperechoic target point of the fascia, precise puncture without X-ray radiation is achieved throughout the entire process, effectively avoiding the potential harm of ionizing radiation to experimental personnel and animals. Real-time ultrasound imaging clearly distinguishes the interface between bony structures and soft tissues, ensuring the safety and controllability of the puncture path, effectively reducing the risk of nerve root, dural sac, or retroperitoneal organ damage. Combining tactile feedback and imaging feedback to verify the needle tip position improves the accuracy and repeatability of model preparation. Postoperatively, multimodal evaluation methods are used to systematically verify the degeneration effect, ensuring the biological reliability of the model. This provides a safe, stable, and radiation-free standardized animal model construction method for the study of intervertebral disc degeneration mechanisms and the development of treatment strategies. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating a minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration model. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0022] Reference Figure 1 As one embodiment of the present invention, this embodiment provides a minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method, comprising: S1. The experimental rabbit was placed in a prone position on the operating table under anesthesia, with its abdomen elevated to maintain lumbar lordosis.

[0023] Furthermore, the experimental rabbits were given general anesthesia; after the rabbits entered a stable state of anesthesia, they were placed on the operating table in a prone position; their limbs were fixed to the four corners of the operating table; and a support pad was placed under their abdomen to allow the lumbar spine area to be naturally extended and fully exposed.

[0024] It should be noted that the experimental rabbits must be kept in a stable prone position and their limbs must be effectively fixed after anesthesia to prevent movement during the operation from interfering with ultrasound imaging and puncture. Elevating the abdomen not only helps maintain the physiological lordosis of the lumbar spine, but also reduces the obstruction of the puncture path by abdominal organs, providing the necessary anatomical conditions for subsequent ultrasound to clearly display the transverse processes and intervertebral disc structures of the lumbar vertebrae.

[0025] S2. Use an ultrasound probe to scan along the longitudinal axis of the spine, identifying the L5 transverse process upwards from the highest point of the iliac crest.

[0026] Furthermore, the ultrasound equipment was activated and a convex array probe was connected; the convex array probe was placed on the skin surface of the lumbosacral region on the tail side of the experimental rabbit; the probe was slowly moved along the midline of the spine towards the head to perform a longitudinal section scan; changes in bony echogenic structures were observed, and the transverse process corresponding to the highest point of the iliac crest was first identified; the scan continued towards the head to locate the clearly shaped and isolated upper-level transverse process, which was confirmed as the L5 transverse process.

[0027] It should be noted that the method of identifying transverse processes step by step from the highest point of the iliac crest can avoid segmental misjudgment caused by anatomical variations in the rabbit lumbar spine; the L5 transverse process, due to its isolated shape and typical echo characteristics, has become a reliable ultrasound positioning landmark, laying the foundation for subsequent precise switching of transverse sections and identification of intervertebral disc spaces.

[0028] S3. Using the identified L5 transverse process as the anatomical reference, locate the L5 / 6 intervertebral disc space in the transverse ultrasound image.

[0029] Furthermore, keep the probe position stable in the L5 transverse process area; rotate the probe 90 degrees, from longitudinal section to transverse section; adjust the probe angle so that the L5 transverse process presents a transverse high-echo strip structure; observe the adjacent area on the inner side of the L5 transverse process and identify the well-defined, elliptical low-echo area; the low-echo area is the location of the L5 / 6 intervertebral disc space.

[0030] It should be noted that changing the probe from a longitudinal section to a transverse section is a key step in achieving visualization of the intervertebral disc. In the transverse section, the L5 / 6 intervertebral disc appears as a hypoechoic oval area on the medial side of the L5 transverse process, with clear boundaries and a sharp contrast with the surrounding hyperechoic bone. This feature makes it a target area that can be clearly identified under ultrasound.

[0031] S4. Confirm the stable hyperechoic target point formed by the fascia in the area where the transverse process head side and the superior articular process ventral side of L5 meet.

[0032] Furthermore, in the transverse image, locate the region above and outside the head of the L5 transverse process; identify a point-like structure with sharp boundaries and higher echo intensity than the surrounding soft tissue within the region; the hyperechoic structure is located at the junction of the ventral side of the superior articular process and the transverse process; confirm that the hyperechoic structure is stable in position and consistent in shape in multiple scans, and use this structure as the ultrasound-guided target point for the puncture path.

[0033] It should be noted that the hyperechoic target is not a random soft tissue echo, but a stable anatomical structure formed by the convergence of the erector spinae fascia at the junction of the superior articular process and the transverse process. This structure has a constant position and higher echo intensity than the surrounding tissue in multiple scans, and can serve as a reliable guiding landmark for the safe entry of the puncture needle into the external opening of the intervertebral foramen, avoiding blind puncture that may cause nerve or blood vessel damage.

[0034] S5. Mark the puncture and needle insertion points on the skin surface based on the hyperechoic target points.

[0035] Furthermore, keep the probe position unchanged and ensure that the hyperechoic target is clearly displayed in the center of the screen; use a marker to draw a straight line on the skin surface along the long axis of the probe; move a distance outward along the line and mark a point on the skin surface as the needle insertion point; after marking, remove the probe and retain the skin surface mark for subsequent puncture operations.

[0036] It should be noted that the surface markings must be completed under real-time ultrasound guidance to ensure that the needle insertion point strictly corresponds to the deep hyperechoic target point; drawing a line along the long axis of the probe and moving the markings outward can ensure that the puncture path avoids the midline spinous process and the spinal canal, while ensuring that the needle tract and the target intervertebral disc are at a reasonable angle, creating geometric conditions for smooth insertion into the intervertebral disc.

[0037] S6. Under real-time ultrasound guidance, perform percutaneous puncture along the marked location, allowing the needle tip to slide along the superior articular process bone surface into the L5 / 6 intervertebral disc. Confirm the needle tip is located in the nucleus pulposus by viscous resistance and a locking-like feel.

[0038] Furthermore, the puncture needle is placed at the marked entry point; the ultrasound probe is repositioned so that the puncture path coincides with the sound beam plane; the puncture needle is slowly advanced under real-time ultrasound monitoring; when the needle tip contacts the superior articular process bone, a strong echoic bright spot with acoustic shadow is observed; the puncture angle is finely adjusted so that the needle tip slides along the bone surface toward the intervertebral disc; when the needle tip passes through the annulus fibrosus and enters the nucleus pulposus, the operator feels a significant change in resistance and a slight unlocking sensation; at the same time, the ultrasound image shows that the needle tip has entered the hypoechoic intervertebral disc region.

[0039] It should be noted that during the puncture process, dual verification is carried out simultaneously using ultrasound imaging and tactile sensation: ultrasound can display the relative position of the needle tip to the bone surface and intervertebral disc in real time, while "viscous resistance" and "unlocking-like" sensation reflect the biomechanical changes as the needle tip breaks through the annulus fibrosus and enters the nucleus pulposus; the combination of the two effectively improves the accuracy of the puncture and avoids punctures that are too deep or deviated.

[0040] S7. Control the needle tip to remain in the intervertebral disc for 10 seconds and maintain the puncture depth at 5 mm to complete the mechanical disturbance to induce disc retraction.

[0041] Furthermore, after confirming that the needle tip is inside the intervertebral disc, stop further needle insertion; maintain the needle body in a stable position without rotating or aspirating; start the timer and keep the needle tip stationary inside the intervertebral disc; continuously observe the ultrasound image during the stationary period to ensure that the needle tip has not shifted; after the preset time has been reached, slowly withdraw the puncture needle.

[0042] After the model was established, anteroposterior and lateral X-ray images of the lumbar spine were taken on the experimental rabbits to verify that the puncture needle tract did not enter the spinal canal and did not cause vertebral fracture or facet joint damage. The success of the model was determined by combining the results of magnetic resonance imaging and histological staining at different time points after the operation.

[0043] After the puncture procedure, the experimental rabbits were transferred to an X-ray examination platform; anteroposterior and lateral X-ray films of the lumbar spine were taken; two or more personnel independently reviewed the films to confirm the absence of pedicle destruction, foreign bodies in the spinal canal, and facet joint fractures; magnetic resonance imaging (MRI) scans were performed on the experimental rabbits at multiple time points postoperatively; after the scans, the animals were euthanized and L5 / 6 intervertebral disc tissue was harvested, and the tissue samples were sequentially fixed, dehydrated, embedded, and sectioned; type II collagen immunohistochemical staining, Masson's trichrome staining, and Safranin O staining were performed; the integrity of the annulus fibrosus structure, changes in nucleus pulposus cell density, and proteoglycan content were observed under a microscope.

[0044] The entire procedure does not require X-ray fluoroscopy and relies entirely on real-time ultrasound imaging to visualize the puncture path, effectively avoiding the potential harm of ionizing radiation to experimental personnel and animals. At the same time, the ability of ultrasound to distinguish between soft tissue and bone interfaces prevents the puncture needle from accidentally entering the spinal canal or damaging nerve roots, thereby preventing serious complications such as lower limb paralysis in experimental rabbits and ensuring the reproducibility and biological effectiveness of the degeneration model.

[0045] It should be noted that the needle tip is left stationary within the intervertebral disc without rotation or aspiration, in order to disrupt the nucleus pulposus matrix structure through limited mechanical disturbance, simulating the pathological process of early degeneration; full-process ultrasound monitoring ensures the stability of the needle tip position and prevents needle displacement due to animal respiration or muscle contraction, thereby ensuring the controllability and consistency of degeneration induction.

[0046] In summary, this invention establishes an ultrasound anatomical positioning system centered on the L5 transverse process and the hyperechoic target point of the fascia, achieving precise puncture without X-ray radiation throughout the entire process. This effectively avoids the potential harm of ionizing radiation to experimental personnel and animals. Real-time ultrasound imaging clearly distinguishes the bony structures and soft tissue interfaces, ensuring a safe and controllable puncture path and effectively reducing the risk of nerve root, dural sac, or retroperitoneal organ damage. Combining tactile feedback and imaging feedback to verify the needle tip position improves the accuracy and repeatability of model preparation. Postoperative multimodal evaluation systematically verifies the degeneration effect, ensuring the biological reliability of the model. This invention provides a safe, stable, and radiation-free standardized animal model construction method for the study of intervertebral disc degeneration mechanisms and the development of treatment strategies.

[0047] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method, characterized in that: include: The experimental rabbits were placed in a prone position on the operating table under anesthesia, with their abdomens elevated to maintain lumbar lordosis. Using an ultrasound probe, scan along the longitudinal axis of the spine to identify the L5 transverse process from the highest point of the iliac crest upwards; Using the identified L5 transverse process as an anatomical reference, the L5 / 6 intervertebral disc space was located in the transverse ultrasound image; Confirm a stable, hyperechoic target point formed by fascia in the area where the head side of the L5 transverse process and the ventral side of the superior articular process meet. Mark the puncture and needle insertion points on the skin surface based on the hyperechoic target points; Under real-time ultrasound guidance, the needle tip was punctured along the marked location and slid into the L5 / 6 intervertebral disc along the superior articular process bone surface. The needle tip was confirmed to be in the nucleus pulposus by viscous resistance and unlocking-like tactile sensation. The needle tip is held within the intervertebral disc for 10 seconds while maintaining a puncture depth of 5 mm to induce mechanical disturbance and induce disc retraction.

2. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 1, characterized in that: The experimental rabbits were anesthetized and fixed prone on the operating table with their abdomen elevated to maintain lumbar lordosis. The specific steps were as follows: The experimental rabbits were given general anesthesia; After the experimental rabbits entered a stable state of anesthesia, they were placed on the operating table in a prone position. Secure the limbs to the four corners of the operating table; Place a support pad under the abdomen to allow the lumbar spine area to stretch naturally and be fully exposed.

3. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 2, characterized in that: The steps for using an ultrasound probe to scan along the longitudinal axis of the spine and identify the L5 transverse process from the highest point of the iliac crest upwards are as follows: Start the ultrasound equipment and connect the convex array probe; The convex array probe was placed on the skin surface of the lumbosacral region on the tail side of the experimental rabbit; Slowly move the probe along the midline of the spine toward the head to perform a longitudinal section scan; To observe changes in bony echogenic structures, first identify the transverse process corresponding to the highest point of the iliac crest; Continuing the scan towards the head, the clearly defined and isolated superior transverse process was identified as the L5 transverse process.

4. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 3, characterized in that: The specific steps for locating the L5 / 6 intervertebral disc space in transverse ultrasound images, using the identified L5 transverse process as the anatomical reference, are as follows: Keep the probe position stable in the L5 transverse process area; Rotate the probe 90 degrees to change the longitudinal section to the transverse section; Adjust the probe angle to make the L5 transverse protrusion appear as a transverse high-echo strip structure; Observe the adjacent area on the inner side of the L5 transverse process to identify a well-defined, elliptical hypoechoic area; The hypoechoic area is the location of the L5 / 6 intervertebral disc space.

5. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 4, characterized in that: The specific steps for identifying a stable hyperechoic target point formed by the fascia in the area where the transverse process head side and the superior articular process ventral side of L5 meet are as follows: In the cross-sectional image, locate the region above and outside the head of the L5 transverse process; Identify a point-like structure within the area with sharp boundaries and an echo intensity higher than the surrounding soft tissue; Among them, the hyperechoic structure is located at the junction of the ventral side of the superior articular process and the transverse process; The hyperechoic structure was confirmed to be stable in position and consistent in shape during multiple scans, and was used as the ultrasound-guided target for the puncture path.

6. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 5, characterized in that: The specific steps for marking the puncture and needle insertion positions on the skin surface based on the hyperechoic target are as follows: Keep the probe position unchanged to ensure that the high-echo target is clearly displayed in the center of the screen; Draw a straight line on the skin surface along the long axis of the probe with a marker; Move a certain distance outward along this straight line and mark a point on the body surface as the needle insertion point; After marking, remove the probe, leaving the surface markings for subsequent puncture procedures.

7. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 6, characterized in that: The procedure involves percutaneous puncture under real-time ultrasound guidance along the marked location, allowing the needle tip to slide along the superior articular process surface into the L5 / 6 intervertebral disc. The needle tip's location within the nucleus pulposus is confirmed by viscous resistance and a "locking" tactile sensation. The specific steps are as follows: Place the puncture needle at the marked insertion point; Reposition the ultrasound probe so that the puncture path coincides with the sound beam plane; The puncture needle was slowly advanced under real-time ultrasound monitoring. When the needle tip touches the bone of the superior articular process, a strong echoic bright spot with acoustic shadowing is observed; Fine-tune the puncture angle so that the needle tip slides along the bone surface toward the intervertebral disc; When the needle tip passes through the annulus fibrosus and enters the nucleus pulposus, the operator feels a significant change in resistance and a slight unlocking sensation; Meanwhile, ultrasound images showed that the needle tip had entered the hypoechoic intervertebral disc region.

8. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 7, characterized in that: The control needle tip remains within the intervertebral disc for 10 seconds while maintaining a puncture depth of 5 mm to induce intervertebral disc degeneration through mechanical disturbance. The specific steps are as follows: Once the needle tip is confirmed to be inside the intervertebral disc, continue needle insertion. Maintain the needle position stable and do not perform rotation or aspiration actions; Start the timer and keep the needle tip still inside the intervertebral disc; During the resting period, continuously observe the ultrasound images to ensure that the needle tip has not shifted; After the preset time has elapsed, slowly withdraw the puncture needle.

9. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 8, characterized in that: After the modeling process is completed, anteroposterior and lateral X-ray images of the lumbar spine are taken in the experimental rabbits to verify that the puncture needle tract did not enter the spinal canal and did not cause vertebral fracture or facet joint damage. The success of the model is determined by combining the results of magnetic resonance imaging and histological staining at different time points after the operation. The specific steps are as follows: After the puncture procedure, the experimental rabbit was transferred to the X-ray examination platform; Take anteroposterior and lateral X-ray films of the lumbar spine; Two or more people independently reviewed the images to confirm that there was no pedicle destruction, no foreign body in the spinal canal, and no facet fracture. Magnetic resonance scanning was performed on the experimental rabbits at multiple time points after the operation. After the scan was completed, the animal was euthanized and L5 / 6 intervertebral disc tissue was taken. The tissue samples were then fixed, dehydrated, embedded, and sectioned in sequence. Immunohistochemical staining for type II collagen, Masson's trichrome staining, and Safranin O staining were performed respectively. The integrity of the annulus fibrosus structure, the density of nucleus pulposus cells, and the changes in proteoglycan content were observed under a microscope.

10. The minimally invasive ultrasound-guided percutaneous rabbit intervertebral disc degeneration modeling method as described in claim 9, characterized in that: The entire procedure does not require X-ray fluoroscopy and relies entirely on real-time ultrasound imaging to visualize the puncture path, effectively avoiding the potential harm of ionizing radiation to experimental personnel and animals. At the same time, the ability of ultrasound to distinguish between soft tissue and bone interfaces prevents the puncture needle from accidentally entering the spinal canal or damaging nerve roots, thereby preventing serious complications such as lower limb paralysis in experimental rabbits and ensuring the reproducibility and biological validity of the degeneration model.

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