This work was supported by Beijing Natural Science Foundation(7202183), National Natural Science Foundation of China(81972107), and Beijing Municipal Science and Technology Commission(D171100003217001).

This study was approved by the ethics committee of the China-Japan Friendship Hospital (approval number: 2021-12-K04). All of the following steps were performed according to standardized procedures to avoid injury to the patients and the surgeons. Informed patient consent was obtained for this study. The surgeon must be skilled in conventional core decompression procedures to ensure that the surgery can be performed in a traditional way in case of inaccurate navigation or other unexpected situations.
1. Preoperative diagnosis and grading of ONFH
<ol>
	<li>Identify patients with clinical symptoms of ONFH; typical symptoms such as persistent or intermittent pain in the groin region with ipsilateral hip or knee radiating pain. Physical examination showed deep tenderness in the groin region, Patrick&#39;s sign, a limited hip motion of internal rotation and abduction, or necrosis changes of the femoral head measured using X-ray, CT, and MRI.</li>
	<li>According to the association research circulation osseous (ARCO) staging, review patients&#39; X-ray, CT, and MRI of the hip and determine the staging of ONFH. Two doctors conduct this work independently. If disagreements arise, ask a third expert to make the final decision.</li>
	<li>Record the preoperative visual analogue scale (VAS) and Harris hip score using a questionnaire.</li>
	<li>Include patients using the following criteria: 1) patients with ONFH; 2) stage I, IIA, and IIB of ONFH confirmed by imaging examination (X-ray, CT, and MRI); 3) the femoral head core decompression surgery is planned. Exclude patients when: 1) patients reject the CD surgery; 2) preoperative routine examination indicates surgical contradictions, such as infection or poor basic condition; 3) patients refuse to be enrolled in the group.</li>
</ol>
2. System registration and accuracy testing
<ol>
	<li>Run the AR-assisted orthopedic surgery system (due to commercialization issues software details cannot be provided) and click on Orthographic Video to activate the depth camera. An image of the surgical area will be displayed on the screen after activation (Figure 5A). Position the optical tracking device so that its tracking area can completely cover the surgical area (Figure 5B).</li>
	<li>Click on NDI Setting to select the device access port, COM4. Click the Virtual Needle Length Setting (generally a Kirschner needle is 180 mm long) and a virtual Kirschner needle image will be automatically generated in the surgical area in the video.</li>
	<li>Divide the planned surgical frontal area into upper and lower levels with each level 30 cm x 30 cm in size, and with a height difference of 15 cm between the levels. The system automatically inputs this spatial information of the surgical area in the software.</li>
	<li>Evenly allocate every level with 10 matching points; for every 30 cm x 30 cm area, divide it into three equal parts, with two parts having three points each, and one part (left part) having four points. Ask the assistant to place the non-invasive body surface marking frame (Figure 2C) according to the points. Once done, click on Match. The system&#39;s own special image for registration will be automatically superimposed on the marking frame (Figure 5C). Consider the registration of this point successful when the image and the marking frame coincide completely.</li>
	<li>Move the frame to the next registration point and repeat step 2.4. until all registration points are completed. As the shape of the marking frame equipped with the puncture device (Figure 3A2) is exactly the same as the non-invasive body surface marking frame, once the registration is completed, the former can also be tracked by the optical tracking device in the surgical area.</li>
	<li>Move the puncture device randomly in the surgical area to detect the matching degree of virtual needle and tracking delay (Figure 6). As the red-blue virtual Kirschner needle body automatically fits with the actual needle in the surgical area, the augmented reality display of the Kirschner needle is successful (Figure 5D). 
	NOTE: During the registration process, the position of the optical tracking device and depth camera should not be changed at will. If so, the spatial position relationship of virtual surgery will change, causing inaccurate matching between the virtual Kirschner needle and the physical one, and registration has to be re-conducted.</li>
</ol>
3. Patient and system preparation before puncture
<ol>
	<li>After entering the operating room, ask the patient to lie down in supine position and fix the lower limb of the affected side (Figure 7). Administer general anesthesia to all patients.</li>
	<li>Prepare the surgical site with iodine and 75% alcohol, and place the non-invasive body surface positioning device (sterilized using standard procedures) on the patient&#39;s affected hip.</li>
	<li>Move the C-ARM fluoroscope to the side of the operating table and position the source above the hip joint. Align the source with the depth camera and record the position of the surgical table as position 1.</li>
	<li>After the first fluoroscopy, export the BMP format radiograph to the system workstation, open it in Photo Editing, and adjust its gray scale by clicking on the Light Scale Option. Rotate clockwise and flip horizontally once by clicking the corresponding buttons to convert to BMP. Then, open it by clicking Painting 3D and save as the JPG format, which contained non-invasive body surface marking frame, and name it image 1 (Figure 8A). 
	NOTE: This conversion process is to promote the success of the system identification. Because of the special requirements of image conversion, it is necessary to adjust the gray scale of the X-ray image for rotation and inversion.</li>
	<li>Slide the operating table directly below the depth camera to the operating area marked as position 2. Position 1 (in step 3.3) and position 2 are two points on the same horizontal plane, 30 cm apart.</li>
	<li>In the AR-assisted orthopedic surgery system, click File &#62; Front X-ray image, and select image 1. the system automatically identifies the non-invasive body surface marking frame on the skin surface of the patient, and then superimposes this image to the hip joint in the surgical video (Figure 8B).</li>
	<li>Using the augmented reality display of the X-ray image and real-time video generated above, the surgeon plans the puncture path based on this.</li>
</ol>
4. Puncture assisted by surgical system
<ol>
	<li>The surgeon stands on the affected side and performs the following steps. Hold the puncture device and determine the best insertion angle. Mark the insertion point on the skin surface, guided by the virtual Kirschner wire and the X-ray image of the hip joint in the surgical video.</li>
	<li>Select a Kirschner wire with a diameter of 2.5 mm and pierce it from the insertion point. Observe the insertion depth and angle in the video and adjust it timely.</li>
	<li>When the virtual needle has reached the target area of necrosis, stop the puncture process and retain the screen shot as image 2 (Figure 9A) for subsequent puncture accuracy evaluation.</li>
	<li>Indwell the needle. Move the operating table to position 1 for the second fluoroscopy to verify the actual puncture condition of the Kirschner wire. Record the image file as image 3 (Figure 9B).</li>
	<li>Puncture is successful when the location of the Kirschner wire meets all of the surgeon&#39;s requirements. Then, use the lancet to cut the skin around the needle, and separate every level of soft tissue till exposing sub-trochanter bone, roughly to a depth of 3 cm. Drill into the necrotic area along the Kirschner wire with a 5 mm trephine to complete the subsequent operations (artificial bone or autologous bone implantation).</li>
	<li>After finishing all the procedures, close the skin with 3-0 silk thread and cover with sterile dressing (Figure 10). After returning to the ward, provide the patients accepted common orthopedic postoperative medication, like infection prevention, analgesia, and fluid infusion. If no complication occurs, discharge the patients 3 days after surgery.</li>
</ol>
5. Operation evaluation
<ol>
	<li>Import image 2 and image 3 into an image processing software and adjust the opacity to 52%.</li>
	<li>Click the Masking button to overlap the two images, then click the Rulers button to measure the distance (Lvirtual) between the virtual tip and the puncture point of the femoral cortex, and the distance (Lture) between the tip of the Kirschner needle and the puncture point of the femoral cortex. Calculate the difference between Lvirtual and Lture to assess puncture accuracy.</li>
	<li>During the puncture, measure the positioning time as follows: the positioning time starts from the time when the Kirschner wire pierces the skin, and stops when the X-ray confirms that the Kirschner wire has successfully reached the target area of the femoral head.</li>
	<li>Three months after surgery, take the hip X-ray (Figure 11) and record the visual analogue scale and Harris hip score.</li>
</ol>

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The authors declare that they have no competing interests.

Although THA has developed rapidly in recent years and become an effective ultimate method for ONFH, hip preservation therapy still plays an important role in treating early-stage ONFH18,19. CD is a basic and effective hip preservation surgery, which can release hip pain and delay the development of femoral head collapse20. The puncture positioning of the focal necrosis is the crucial procedure of CD, as it determines the success or failur...

Osteonecrosis of the femoral head (ONFH) is a common disabling disease occurring in young adults1. Clinically, it is necessary to determine the staging of ONFH based on X-ray, CT, and MRI to decide the treatment strategy (Figure 1). For early-stage ONFH, hip preservation therapy is usually adopted2. Core decompression (CD) surgery is one of the most frequently used hip preservation methods for ONFH. Certain curative effects of core decompression with or without bone grafting in treating early-stage ONFH have been reported, which can avoid or delay subsequent total hip arthroplasty (THA) for a long time3,4,5. However, the success rate of CD with or without bone grafting was reported differently among previous studies, from 64% to 95%6,7,8,9. The surgical technique, especially the accuracy of drilling position, is important for the success of hip preservation10. Due to the blindness of the puncture and positioning procedure, the traditional techniques of CD have several problems, such as more fluoroscopy time, repeated puncture using Kirschner wire, and injury of normal bone tissue11,12.
In recent years, the augmented reality (AR)-assisted method has been introduced in orthopedic surgery13. The AR technique can visually show the anatomy of the surgical field, guide the surgeons in planning the operating procedure, and consequently reduce the difficulty of the operation. The applications of the AR technique in pedicle screw implantation and joint arthroplasty surgery have been reported earlier14,15,16,17. In this study, we aim to apply the AR technique to the CD procedure and verify its safety, accuracy, and feasibility in clinical practice.
System hardware components 
The main components of the AR-based navigation surgical system include the following: (1) A depth camera (Figure 2A) installed directly above the surgical area; the video is shot from this and sent back to the workstation for registration and cooperation with the imaging data. (2) A puncture device (Figure 2B) and a non-invasive body surface marking frame (Figure 2C), both with passive infrared reflectors. A special reflective coating of marking balls (Figure 3) can be captured by infrared equipment to achieve accurate tracking of surgical equipment in the surgical area. (3) An infrared positioning device (Figure 2D) is responsible for tracking markers in the surgical area, matching the body surface marking frame and puncture device with high accuracy (Figure 4). (4) The host system (Figure 2E) is a 64-bit workstation, installed with the independently developed AR-assisted orthopedic surgery system. Augmented reality display of hip joint and femoral head puncture operation can be completed with its assistance.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AR-assisted Orthopedic Surgery System</td>
			<td>Self development</td>
			<td>None</td>
			<td>An operating software that implements AR for orthopedic surgery</td>
		</tr>
		<tr>
			<td>Depth camera</td>
			<td>Stereolabs</td>
			<td>ZED depth camera(ZED mini)</td>
			<td>shoot video and sent back to the workstation.</td>
		</tr>
		<tr>
			<td>Image processing software</td>
			<td>Adobe Systems Incorporated</td>
			<td>Adobe Photoshop CS6</td>
			<td>Image processing software</td>
		</tr>
		<tr>
			<td>Infrared positioning device</td>
			<td>Northern Digital Inc.</td>
			<td>NDI Polaris Spectra optical tracking device</td>
			<td>Tracking markers in the surgical area.</td>
		</tr>
		<tr>
			<td>Puncture device</td>
			<td>Stryker</td>
			<td>Stryker System 7 Cordless driver and Sabo</td>
			<td>Insert kirschner wire into the necrotic area.</td>
		</tr>
	</tbody>
</table>

augmented reality navigation-guided core decompression for osteonecrosis of femoral head

Osteonecrosis of the femoral head (ONFH) is a common joint disease in young and middle-aged patients, which seriously burdens their lives and work. For early-stage ONFH, core decompression surgery is a classical and effective hip preservation therapy. In traditional procedures of core decompression with Kirschner wire, there are still many problems such as X-ray exposure, repeated puncture verification, and damage to normal bone tissue. The blindness of the puncture process and the inability to provide real-time visualization are crucial reasons for these problems.
To optimize this procedure, our team developed an intraoperative navigation system on the basis of augmented reality (AR) technology. This surgical system can intuitively display the anatomy of the surgical areas and render preoperative images and virtual needles to intraoperative video in real-time. With the guide of the navigation system, surgeons can accurately insert Kirschner wires into the targeted lesion area and minimize the collateral damage. We conducted 10 cases of core decompression surgery with this system. The efficiency of positioning and fluoroscopy is greatly improved compared to the traditional procedures, and the accuracy of puncture is also guaranteed.

Operation characteristics 
The surgical navigation system was applied in continuative 10 hips of nine patients. The average total positioning time of the surgery was 10.1 min (median 9.5 min, range 8.0-14.0 min). The mean C-ARM fluoroscopies was 5.5 times (median 5.5 times, range 4-8 times). The mean error of puncture accuracy was 1.61 mm (median 1.2 mm, range -5.76-19.73 mm; Table 1). The results show that the positioning time and fluoroscopy times are obviously shortened compared ...

Watch this Scientific Journal Video about Augmented Reality Navigation-Guided Core Decompression for Osteonecrosis of Femoral Head at JoVE.com

Augmented Reality Navigation-Guided Core Decompression for Osteonecrosis of Femoral Head

Augmented reality technology was applied to core decompression for osteonecrosis of the femoral head to realize real-time visualization of this surgical procedure. This method can effectively improve the safety and precision of core decompression.

Osteonecrosis of the femoral head (ONFH) is a common joint disease in young and middle-aged patients, which seriously burdens their lives and work. For ...

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3.5K Views.  Peking University. Augmented reality technology was applied to core decompression for osteonecrosis of the femoral head to realize real-time visualization of this surgical procedure. This method can effectively improve the safety and precision of core decompression.

Video: Augmented Reality Navigation-Guided Core Decompression for Osteonecrosis of Femoral Head

Integrating Augmented Reality Tools in Breast Cancer Related Lymphedema Prognostication and Diagnosis

Breast cancer related lymphedema (BCRL) is a detrimental condition characterized by fluid accumulation in the upper limb in breast cancer patients subjected to axillary surgery and/or radiations. Its etiology is multifactorial and include also tumor-specific pathological features, such as lymphovascular invasion (LVI) and extranodal extension (ENE). To date, no widely employed guidelines for the early diagnosis of BCRL are available. Here, we illustrate a protocol for a digitally assisted BCRL assessment using a 3D laser scanner (3DLS) and a tablet computer. It has been specifically optimized in a discovery cohort of high-risk breast cancer patients. This study provides a proof-of-principle that augmented reality tools, such as 3DLS, can be incorporated into the clinical workup of BCRL to allow for a precise, reproducible, reliable, and cheap diagnosis.

Breast cancer related lymphedema is frequent in breast cancer survivors, but there are not widely employed guidelines for its diagnosis and quantification. Here, we introduce a reliable and cost-effective protocol to define, quantify, and compare upper limb volume in breast cancer patients.

Breast cancer related lymphedema (BCRL) is a detrimental condition characterized by fluid accumulation in the upper limb in breast cancer patients ...

Combining Augmented Reality and 3D Printing to Display Patient Models on a Smartphone

Augmented reality (AR) has great potential in education, training, and surgical guidance in the medical field. Its combination with three-dimensional (3D) printing (3DP) opens new possibilities in clinical applications. Although these technologies have grown exponentially in recent years, their adoption by physicians is still limited, since they require extensive knowledge of engineering and software development. Therefore, the purpose of this protocol is to describe a step-by-step methodology enabling inexperienced users to create a smartphone app, which combines AR and 3DP for the visualization of anatomical 3D models of patients with a 3D-printed reference marker. The protocol describes how to create 3D virtual models of a patient&rsquo;s anatomy derived from 3D medical images. It then explains how to perform positioning of the 3D models with respect to marker references. Also provided are instructions for how to 3D print the required tools and models. Finally, steps to deploy the app are provided. The protocol is based on free and multi-platform software and can be applied to any medical imaging modality or patient. An alternative approach is described to provide automatic registration between a 3D-printed model created from a patient&rsquo;s anatomy and the projected holograms. As an example, a clinical case of a patient suffering from distal leg sarcoma is provided to illustrate the methodology. It is expected that this protocol will accelerate the adoption of AR and 3DP technologies by medical professionals.

Presented here is a method to design an augmented reality smartphone application for the visualization of anatomical three-dimensional models of patients using a 3D-printed reference marker.

Augmented reality (AR) has great potential in education, training, and surgical guidance in the medical field. Its combination with three-dimensional (3D) ...

Orthopedic Robot-Assisted Femoral Neck System in the Treatment of Femoral Neck Fracture

Cannulated screw fixation is the main therapy for femoral neck fractures, especially in young patients. The traditional surgical procedure uses C-arm fluoroscopy to place the screw freehand and requires several guide wire adjustments, which increases the operation time and radiation exposure. Repeated drilling can also cause damage to the blood supply and bone quality of the femoral neck, which can be followed by complications such as screw loosening, nonunion, and femoral head necrosis. In order to make fixation more precise and reduce the incidence of complications, our team applied robot-assisted orthopedic surgery for screw placement using the femoral neck system to modify the traditional procedure. This protocol introduces how to import a patient's X-ray information into the system, how to perform screw path planning in software, and how the robotic arm assists in screw placement. Using this method, the surgeons can place the screw successfully the first time, improve the accuracy of the procedure, and avoid radiation exposure. The whole protocol includes the diagnosis of femoral neck fracture; the collection of intraoperative X-ray images; screw path planning in the software; precise placement of the screw under the assistance of the robotic arm by the surgeon; and verification of the implant placement.

This article introduces a method of robot-assisted orthopedic surgery for screw placement during the treatment of femoral neck fracture using the femoral neck system, which allows for more accurate screw placement, improved surgical efficiency, and fewer complications.

Cannulated screw fixation is the main therapy for femoral neck fractures, especially in young patients. The traditional surgical procedure uses C-arm ...

Advanced CAD Imaging for Surgical Margin Analysis in Cancer Care

Enhanced Communication of Tumor Margins Using 3D Scanning and Mapping

After oncologic resection of malignant tumors, specimens are sent to pathology for processing to determine the surgical margin status. These results are communicated in the form of a written pathology report. The current standard-of-care pathology report provides a written description of the specimen and the sites of margin sampling without any visual representation of the resected tissue. The specimen itself is typically destroyed during sectioning and analysis. This often leads to challenging communication between pathologists and surgeons when the final pathology report is confirmed. Furthermore, surgeons and pathologists are the only members of the multidisciplinary cancer care team to visualize the resected cancer specimen. We have developed a 3D scanning and specimen mapping protocol to address this unmet need. Computer-aided design (CAD) software is used to annotate the virtual specimen clearly showing sites of inking and margin sampling. This map can be utilized by various members of the multidisciplinary cancer care team.

Author Spotlight: 3D Scanning and Augmented Reality for Enhanced Cancer Surgery Communication

A novel method for 3D scanning and virtual mapping of cancer resections is proposed with the goal of improving communication among the multidisciplinary cancer care team.

After oncologic resection of malignant tumors, specimens are sent to pathology for processing to determine the surgical margin status. These results are ...

Treating Lumbar Spinal Stenosis with a Minimally Invasive Spine Surgery

Percutaneous Endoscopic Unilateral-Approach Bilateral Decompression for Lumbar Spinal Stenosis

Lumbar spinal stenosis (LSS) involves the narrowing of the spinal canal due to degenerative changes in the vertebral joints, intervertebral discs, and ligaments. LSS encompasses central canal stenosis (CCS), lateral recess stenosis (LRS), and intervertebral foramen stenosis (IFS). The utilization of lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) has gained popularity in the treatment of CCS and LRS. This popularity is attributed to the rapid development of endoscopic instruments and the progress of endoscopic philosophy.
In this technical report, a detailed introduction to the steps and key points of LE-ULBD is provided. Simultaneously, a retrospective review of 132 consecutive patients who underwent LE-ULBD for central canal and/or lateral recess stenosis was conducted. The outcomes after more than two years of follow-up were assessed using the visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, and the modified MacNab criteria to evaluate surgical efficacy. All 132 patients underwent LE-ULBD successfully. Among them, 119 patients were rated as "excellent," while 13 patients were rated as "good" based on the modified MacNab criteria during the last follow-up. Incidental dural tears occurred in four cases, but there were no post-operative epidural hematomas or infections. The experience demonstrates that LE-ULBD is a less invasive, effective, and safe approach. It can be considered as an alternative option for treating patients with lumbar central canal stenosis and/or lateral recess stenosis.

Author Spotlight: Scope of LE-ULBD as a Safe, Effective, and Minimally Invasive Approach to Treat Lumbar Spinal Stenosis

The present protocol describes the steps and key points of lumbar endoscopic unilateral laminotomy for bilateral decompression for the treatment of degenerative lumbar spinal stenosis.

Lumbar spinal stenosis (LSS) involves the narrowing of the spinal canal due to degenerative changes in the vertebral joints, intervertebral discs, and ...

Pedicle Screw Placement Using an Augmented Reality Head-Mounted Display in a Porcine Model

This protocol helps assess the accuracy and workflow of an augmented reality (AR) hybrid navigation system using the Magic Leap head-mounted display (HMD) for minimally invasive pedicle screw placement. The cadaveric porcine specimens were placed on a surgical table and draped with sterile covers. The levels of interest were identified using fluoroscopy, and a dynamic reference frame was attached to the spinous process of a vertebra in the region of interest. Cone beam computerized tomography (CBCT) was performed, and a 3D rendering was automatically generated, which was used for the subsequent planning of the pedicle screw placements. Each surgeon was fitted with an HMD that was individually eye-calibrated and connected to the spinal navigation system.
Navigated instruments, tracked by the navigation system and displayed in 2D and 3D in the HMD, were used for 33 pedicle cannulations, each with a diameter of 4.5 mm. Postprocedural CBCT scans were assessed by an independent reviewer to measure the technical (deviation from the planned path) and clinical (Gertzbein grade) accuracy of each cannulation. The navigation time for each cannulation was measured. The technical accuracy was 1.0 mm &#177; 0.5 mm at the entry point and 0.8 mm &#177; 0.1 mm at the target. The angular deviation was 1.5&#176; &#177; 0.6&#176;, and the mean insertion time per cannulation was 141 s &#177; 71 s. The clinical accuracy was 100% according to the Gertzbein grading scale (32 grade 0; 1 grade 1). When used for minimally invasive pedicle cannulations in a porcine model, submillimeter technical accuracy and 100% clinical accuracy could be achieved with this protocol.

The augmented reality head-mounted display, Magic Leap, was used in combination with a conventional navigation system to place pedicle screws in a porcine model by adhering to a novel workflow. With a median insertion time of &lt;2.5 min, submillimeter technical accuracy and 100% clinical accuracy were achieved according to Gertzbein.

This protocol helps assess the accuracy and workflow of an augmented reality (AR) hybrid navigation system using the Magic Leap head-mounted display (HMD) ...

Optimized 3D Reconstruction and Motion Mapping for Remote AR-Assisted Surgery

Automatic Surgery in Transcatheter Aortic Valve Replacement Using Augmented Reality

Augmented Reality (AR) is in high demand in medical applications. The aim of the paper is to provide automatic surgery using AR for the Transcatheter Aortic Valve Replacement (TAVR). TAVR is the alternate medical procedure for open-heart surgery. TAVR replaces the injured valve with the new one using a catheter. In the existing model, remote guidance is given, while the surgery is not automated based on AR. In this article, we deployed a spatially aligned camera that is connected to a motor for the automation of image capture in the surgical environment. The camera tracks the 2D high-resolution image of the patient's heart along with the catheter testbed. These captured images are uploaded using the mobile app to a remote surgeon who is a cardiology expert. This image is utilized for the 3D reconstruction from 2D image tracking. This is viewed in a HoloLens like an emulator in a laptop. The surgeon can remotely inspect the 3D reconstructed images with additional transformation features such as rotation and scaling. These transformation features are enabled through hand gestures. The surgeon's guidance is transmitted to the surgical environment to automate the process in real-time scenarios. The catheter testbed in the surgical field is controlled by the hand gesture guidance of the remote surgeon. The developed prototype model demonstrates the effectiveness of remote surgical guidance through AR.

Author Spotlight: Revolutionizing Remote Surgery with Augmented Reality and Robotics for Enhanced Precision and Accessibility

This article presents the design and implementation of an automatic surgery module based on augmented reality (AR)- based 3D reconstruction. The system enables remote surgery by allowing surgeons to inspect reconstructed features and replicate surgical hand movements as if they were performing the surgery in close proximity.

Augmented Reality (AR) is in high demand in medical applications. The aim of the paper is to provide automatic surgery using AR for the Transcatheter ...

Relieving Occipital Neuralgia: Nerve and Muscle-Preserving Decompression

Minimally Invasive Surgical Decompression of Occipital Nerves

Occipital neuralgia (ON) stands out as one of the most distressing forms of headache disorders, distinguished by persistent pain at the base of the skull, recurring occipital headaches, and scalp dysesthesia or allodynia. ON is notorious for its unrelenting agony, severely impacting the lives of those afflicted. The incessant pain, often radiating upward from the base of the skull to the scalp, can be profoundly debilitating. Patients frequently endure excruciating occipital headaches, making even routine daily activities a formidable challenge. The added burden of scalp dysesthesia or allodynia, where seemingly innocuous stimuli elicit severe pain, compounds the suffering. This neuralgia primarily arises from the mechanical compression exerted on the occipital nerves along the nuchal line. In this paper, we present a minimally invasive nerve and muscle-preserving technique aimed at relieving this compression on the occipital nerves. Accurate diagnosis and effective treatment are paramount in providing relief for individuals battling this condition. Nerve blocks with local anesthesia have become a cornerstone of diagnosis, serving as both a confirmation of occipital neuralgia and a potential therapeutic intervention. These procedures offer crucial insights into the source of the pain while offering transient respite. However, the true breakthrough lies in the innovative technique we propose - a procedure that addresses the mechanical compression at the nuchal line, which is a prominent contributing factor to occipital neuralgia. By carefully decompressing the affected occipital nerves while preserving their integrity and surrounding muscle tissue, this minimally invasive approach offers patients a potential path to sustained relief. Remarkably, the procedure can be performed under local anesthesia, reducing the invasiveness of traditional surgeries and minimizing patient downtime.

Author Spotlight: Minimally Invasive Relief for Occipital Neuralgia at the Nuchal Line

The manuscript presents a minimally invasive nerve and muscle-sparing surgical protocol to decompress occipital nerves aiming to improve occipital neuralgia.

Occipital neuralgia (ON) stands out as one of the most distressing forms of headache disorders, distinguished by persistent pain at the base of the skull, ...

Elastic Tape Rat Model of Steroid-Induced Femoral Head Osteonecrosis Enhancement

Tension-Free Weight-Bearing Model of Steroid-Induced Osteonecrosis of Femoral Head in Rats

Unlike humans, rats are animals that walk on all fours, while humans are bipedal animals that stand, and the hips are subjected to tremendous pressure when walking and standing. In rat steroid-induced femoral head necrosis models, the biomechanical characteristics of the human hip under higher pressure often need to be simulated. Some scholars try to emulate the state of human hip pressure by making rats bear a certain weight, but fixing the weight-bearing object on the rat is tough. Rats can easily break free of immobilization, and sticking the weight on the rats with adhesive tape will cause the rats to suffocate or die from intestinal obstruction. Our research group used elastic therapeutic tape to perform tension-free immobilization of weight-bearing objects in rats so that the rats could breathe freely and not break away from the immobilization under weight-bearing conditions. Compared to the usual steroid-induced femoral head necrosis rat model, we found that this weight-bearing intervention can aggravate the progression of femoral head necrosis in rats.

Author Spotlight: Developing a Rat Model for Weight-Bearing Intervention to Investigate Osteonecrosis of the Femoral Head

The protocol shows building a simple and cost-effective rat weight-bearing training model for steroid-induced osteonecrosis of the femoral head using elastic therapeutic tape.

Unlike humans, rats are animals that walk on all fours, while humans are bipedal animals that stand, and the hips are subjected to tremendous pressure ...