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 ...

augmented-reality-navigation-guided-core-decompression-for

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

3.6K 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

A Simple Critical-sized Femoral Defect Model in Mice

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all limb bone fractures fail to heal completely due to the extent of the trauma, disease, or age of the patient. Our ability to improve bone regenerative strategies is critically dependent on the ability to mimic serious bone trauma in test animals, but the generation and stabilization of large bone lesions is technically challenging. In most cases, serious long bone trauma is mimicked experimentally by establishing a defect that will not naturally heal. This is achieved by complete removal of a bone segment that is larger than 1.5 times the diameter of the bone cross-section. The bone is then stabilized with a metal implant to maintain proper orientation of the fracture edges and allow for mobility. 
Due to their small size and the fragility of their long bones, establishment of such lesions in mice are beyond the capabilities of most research groups. As such, long bone defect models are confined to rats and larger animals. Nevertheless, mice afford significant research advantages in that they can be genetically modified and bred as immune-compromised strains that do not reject human cells and tissue.
Herein, we demonstrate a technique that facilitates the generation of a segmental defect in mouse femora using standard laboratory and veterinary equipment. With practice, fabrication of the fixation device and surgical implantation is feasible for the majority of trained veterinarians and animal research personnel. Using example data, we also provide methodologies for the quantitative analysis of bone healing for the model.

Animal models are frequently employed to mimic serious bone injury in biomedical research. Due to their small size, establishment of stabilized bone lesions in mice are beyond the capabilities of most research groups. Herein, we describe a simple method for establishing and analyzing experimental femoral defects in mice.

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all ...

A Repetitive Concussive Head Injury Model in Mice

Despite the concussion/ mild traumatic brain injury (mTBI) being the most frequent occurrence of traumatic brain injury, there is still a lack of knowledge on the injury and its effects. To develop a better understanding of concussions, animals are often used because they provide a controlled, rigorous, and efficient model. Studies have adapted traditional animal models to perform mTBI to stimulate mild injury severity by changing the injury parameters. These models have been used because they can produce morphologically similar brain injuries to the clinical condition and provide a spectrum of injury severities. However, they are limited in their ability to present the identical features of injuries in patients. Using a traditional impact system, a repetitive concussive injury (rCHI) model can induce mild to moderate human-like concussion. The injury degree can be determined by measuring the period of loss of consciousness (LOC) with a sign of a transient termination of breathing. The rCHI model is beneficial to use for its accuracy and simplicity in determining mTBI effects and potential treatments.

Concussion presents the most common type of traumatic brain injury. Therefore, a repetitive concussive animal model, which replicates the important features of an injury in patients, may provide a means to study concussion in a rigorous, controlled, and efficient manner.

Despite the concussion/ mild traumatic brain injury (mTBI) being the most frequent occurrence of traumatic brain injury, there is still a lack of ...

Ultrasonic-augmented Primary Adult Fibroblast Isolation

Primary adult fibroblasts have become an important tool to study fibrosis, fibroblast interactions and inflammation in all body tissues. Since primary fibroblasts cannot divide indefinitely due to myofibroblast differentiation or senescence induction, new cultures must be established regularly. However, there are several obstacles to overcome during the processes of developing a reliable isolation protocol and primary fibroblast isolation itself: the method&#8217;s degree of difficulty (especially for beginners), the risk of bacterial contamination, the required time until primary fibroblasts can be used for experiments, and subsequent cell quality and viability. In this study, a fast, reliable and easy-to-learn protocol to isolate and culture primary adult fibroblasts from mouse heart, lung, liver and kidney combining enzymatic digestion and ultrasonic agitation is provided.

We present a protocol to isolate primary adult fibroblasts in an easy, fast and reliable way, performable by beginners (e.g., students). The procedure combines enzymatic tissue digestion and mechanical agitation with ultrasonic waves to obtain primary fibroblasts. The protocol can easily be adapted to specific experimental requirements (e.g., human tissue).

Primary adult fibroblasts have become an important tool to study fibrosis, fibroblast interactions and inflammation in all body tissues. Since primary ...

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 ...

Immunofluorescence Labelling of Human and Murine Neutrophil Extracellular Traps in Paraffin-Embedded Tissue

Neutrophil granulocytes, also called polymorphonuclear leukocytes (PMN) due to their lobulated nucleus, are the most abundant type of leukocytes. They mature in the bone marrow and are released into the peripheral blood, where they circulate for about 6&#8722;8 h; however, in tissue, they can survive for days. By diapedesis through the endothelium, they leave the blood stream, enter tissues, and migrate towards the site of an infection following chemotactic gradients.&#160;Neutrophils can combat invading microorganisms by phagocytosis,&#160;degranulation, and generation of neutrophil extracellular traps (NETs). This protocol will help to detect NETs in paraffin-embedded tissue. NETs are the result of a process called NETosis, which leads to the release of nuclear, granular, and cytoplasmic components either from living (vital NETosis) or dying (suicidal NETosis) neutrophils. In vitro, NETs form cloud-like structures, which occupy a space several times larger than that of the cells from which they descended. The backbone of NETs is chromatin, to which a selection of proteins and peptides originating from granules and cytoplasm are bound. Thereby, a high local concentration of toxic compounds is maintained so that NETs can capture and inactivate a variety of pathogens including bacteria, fungi, viruses, and parasites, while diffusion of the highly active NET components leading to damage in neighboring tissue is limited. Nevertheless, in recent years it has become apparent that NETs, if generated in abundance or cleared insufficiently, do have pathological potential ranging from autoimmune diseases to cancer. Thus, detection of NETs in tissue samples may have diagnostic significance, and the detection of NETs in diseased tissue can influence the treatment of patients. Since paraffin-embedded tissue samples are the standard specimen used for pathological analysis, it was sought to establish a protocol for fluorescent staining of NET components in paraffin-embedded tissue using commercially available antibodies.

Neutrophil extracellular traps (NETs) are three-dimensional structures generated by stimulated neutrophil granulocytes. It has become clear in recent years that NETs are involved in a wide variety of diseases. Detection of NETs in tissue may have diagnostic relevance, so standardized protocols for labelling NET components are required.

Neutrophil granulocytes, also called polymorphonuclear leukocytes (PMN) due to their lobulated nucleus, are the most abundant type of leukocytes. They ...

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) ...

A Heterotopic Mouse Model for Studying Laryngeal Transplantation

Laryngeal heterotopic transplantation, although a technically challenging procedure, offers more scientific analysis and cost benefits compared to other animal models. Although first described by Shipchandler et al. in 2009, this technique is not widely used, possibly due to the difficulties in learning the microsurgical technique and time required to master it. This paper describes the surgical steps in detail, as well as potential pitfalls to avoid, in order to encourage effective use of this technique.
In this model, the bilateral carotid arteries of the donor larynx are anastomosed to the recipient carotid artery and external jugular vein, allowing for blood flow through the graft. Blood flow can be confirmed intraoperatively by the visualization of blood filling in the graft bilateral carotid arteries, reddening of the thyroid glands of the graft, and bleeding from micro vessels in the graft. The crucial elements for success include delicate preservation of the graft vessels, making the correct size arteriotomy and venotomy, and using the appropriate number of sutures on the arterial-arterial and arterial-venous anastomoses to secure vessels without leakage and prevent occlusion. 
Anyone can become proficient in this model with sufficient training and perform the procedure in approximately 3 h. If performed successfully, this model allows for immunologic studies to be performed with ease and at low cost.

The aim of this manuscript is to describe the microsurgical steps required to perform a heterotopic laryngeal transplant in mice. The advantages of this mouse model compared to other animal models of laryngeal transplantation are its cost-effectiveness and the availability of immunologic assays and data.

Laryngeal heterotopic transplantation, although a technically challenging procedure, offers more scientific analysis and cost benefits compared to other ...

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 ...

Robot-Assisted Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma

Congenital cholesteatoma accounts for 25% of cholesteatoma cases in children. Transcanal Endoscopic Ear Surgery (TEES) is ideal for these patients because it offers a wide endoscopic view of the middle ear and a minimally invasive approach. The two main limitations are the loss of one operative hand and a narrow external auditory canal in younger children. Here, we present the case of a 3-year-old patient with a Potsic stage III congenital cholesteatoma adherent to the incus and branches of the stapes. A robotic-assisted TEES procedure was performed, during which a robotic arm with 6 degrees of freedom held a 0&#176;, 2.9 mm wide endoscope, enabling the surgeon to work in a narrow environment with both hands. The procedure's duration was 2 h and 9 min, including 16 min for the installation and draping of the robotic arm. After a trans-canal approach, the cholesteatoma was dissected from the ossicles using both a needle (or sickle knife) and suction to stabilize the ossicles and limit the risk of hearing trauma. The cholesteatoma was debulked to reduce its size, allowing it to be pushed under the malleus anteriorly and then separated from other adherences before removal. A tragal cartilage graft was used to reinforce the tympanic membrane.

This protocol describes the removal of congenital cholesteatoma using minimally invasive transcanal endoscopic ear surgery with a two-handed approach and a robotic endoscope holder.

Congenital cholesteatoma accounts for 25% of cholesteatoma cases in children. Transcanal Endoscopic Ear Surgery (TEES) is ideal for these patients because ...

Novel PLL-AF Suture Technique for Annulus Fibrosus Repair in Lumbar Endoscopy

A Suture Technique for Ruptured Annulus Fibrosus Following Decompression Under Percutaneous Transforaminal Endoscopic Discectomy

The suture technique for a ruptured annulus fibrosus (AF) under full-endoscopy remains challenging. Direct suturing of a ruptured annular tear after full decompression has been shown to decrease the recurrence rate of lumbar disc herniation during endoscopic surgery. Traditional suture operations under endoscopy involve only simple suturing of the ruptured AF. Due to the weak and poor quality of the AF tissue around the tear portal, using this area as needle insertion points during suturing may lead to insufficient tension and a low success rate of AF closure. Currently, there is no detailed technical illustration based on video for AF tear suturing under lumbar full-endoscopy. We innovatively propose a method of covering and suturing the AF tear by pulling up the posterior longitudinal ligament (PLL) under lumbar endoscopy and using three stitches (PLL-AF suture technique). The patient who received the novel suture technique achieved satisfactory results. Six months after the operation, lumbar MRI showed no evidence of recurrence in the outpatient clinic.

Author Spotlight: Development and Application of a Novel Suture Technique for Annular Fibrosus Repair in Percutaneous Transforaminal Endoscopic Discectomy

This protocol describes an innovative suture technique for ruptured annular fibrosus during percutaneous transforaminal endoscopic discectomy.

The suture technique for a ruptured annulus fibrosus (AF) under full-endoscopy remains challenging. Direct suturing of a ruptured annular tear after full ...