The study was funded by Beijing Natural Science Foundation-Haidian Original Innovation Joint Fund (L232054) and Capital Health Development Research Special Fund (NO.2024-2-2024).

The present study was approved by the Ethics Committee of Beijing Friendship Hospital Capital Medical University. This method will be introduced via a retrospective case study, utilizing only the preoperative prone-position computed tomography (CT) imaging data of the patient. The &#34;Nine-grid Area Division Method&#34; in assisted percutaneous vertebroplasty (PVP) offers a simpler and more effective approach compared to traditional methods, resulting in reduced surgical and radiation exposure times. This technique may benefit young residents by facilitating easier identification of puncture points and potentially shortening the learning curve for PVP procedures, warranting further investigation. The individual described here is a female of 68 years of age.
1. Diagnosing osteoporotic vertebral compression fracture (OVCF) using X-ray fluoroscopy, magnetic resonance image (MRI), bone scintigraphy, and symptoms
<ol>
	<li>Identify the patient who has OVCF among older patients with symptoms such as back pain, tenderness in the spinous process, and paraspinal muscles at the back. Utilize posteroanterior X-ray fluoroscopy to assess for the presence of a vertebral compression fracture at the L1 level (Figure 2A). Employ MRI imaging to confirm the diagnosis of a newly occurring lumbar vertebral compression fracture and identify the specific vertebra affected, which is determined to be L1 (Figure 2B).</li>
</ol>
2. The preoperative acquisition of CT imaging of the patient in a prone position
<ol>
	<li>Place the patient in a prone position to perform prone CT on the patient. Confirm the target area by x-ray fluoroscopy and a physical examination of the patient&#39;s back while pressing the most painful part.</li>
	<li>Make the patient lie in a prone position on the operation table, place a gradienter on the patient&#39;s back before the prone CT scan, record the patient&#39;s body position, and then remove the gradienter (Figure 3).</li>
	<li>Save the CT images (1 mm scanning layer thickness, 1 mm layer spacing, and either 90 slices (conventional scanning) or 400 slices (thin slice scanning) in DICOM format.</li>
</ol>
3. Establish the 3-D model and simulate the operation in medical imaging processing software
<ol>
	<li>Export the CT images in DICOM format into medical imaging processing software by clicking New Project. Select the desired slices for reconstructing the compressed vertebra.</li>
	<li>Utilize the Threshold Segmentation tool to adjust the threshold range for the target vertebra, specifically within the range of 125-3071 H to create a mask. Employ the Duplicate Mask function to generate two separate masks, Mask A and Mask B.</li>
	<li>Utilize the Mask Edit feature to erase the target vertebra from Mask A. Subsequently, utilize the Boolean Operations tool to subtract Mask A from Mask B, resulting in the formation of a new mask, Mask C. Finally, activate the Calculate 3-D function to reconstruct the target vertebra using the Mask C; name this 3-D model L1 (Figure 4A).</li>
	<li>Right-click on New in the Objects interface, choose Draw, and subsequently select Cylinder. Ensure that the cylinder has the same dimensions as the puncture needle, with a length of 12.5 mm and a radius of 1.25 mm.</li>
	<li>Adjust the positioning of the cylinder using the Move and Rotate function to achieve the ideal position (Figure 4B). Throughout the simulation, take care to maintain needle trajectories consistent with established principles: the puncture needle must be able to traverse the pedicle, preferably in its superior half, and the optimal positioning of the tips is within the anterior one-third of the vertebral body on the lateral view.</li>
	<li>Right-click on L1 in the Objects interface, choose Export STL, and subsequently export the file in STL format.</li>
</ol>
4. Polish the 3-D model in 3-D reverse engineering production software
<ol>
	<li>Import the exported vertebral body solid file into the 3-D reverse engineering production software by clicking Import. Consequently, employ the Mesh Doctor feature to eliminate distortions and spikes from the model.</li>
	<li>As the Grid Doctor function may mistakenly identify normal anatomical structures as distortions or spikes, take care to thoroughly examine the rough model to identify any internal voids, and follow step 4.1 to fill them appropriately (Figure 5A).</li>
	<li>Employ the Precise Surface function to transform the solid model into a triangular mesh surface, opting for the Organic Geometry Material (Figure 5B). Await the completion of the automated surface construction process and subsequently export the file in STP format.</li>
</ol>
5. Reconstruct the vertebral engineering model and confirm the safe entry regions of pedicle projection in 3-D modeling design software
<ol>
	<li>Import the STP format of the precise surface document into 3-D modeling design software to reconstruct the vertebral engineering model by clicking Open. Employ the Section View feature to examine the pedicle&#39;s morphology in horizontal, sagittal, and coronal orientations, providing an initial observation of the pedicle&#39;s morphology and structure (Figure 6A).</li>
	<li>In the Section View panel, adjust the angle of the section for optimal visualization. By utilizing Transparency Section Bodies, observe the narrowest point of the pedicles (Figure 6B) and record the angle parameters at Section 1 in the left panel.</li>
	<li>To adjust the angle of the vertebral model, click on the Insert-Features-Move/Copy function and select the Translate/Rotate button located at the bottom of the left panel. Revisit the Section View panel and adjust the view angle parameter in Section 1 to 0.</li>
	<li>Fine-tune the displacement parameters in the Section 1 panel to attain a satisfactory pedicle section view. Reorient for an improved perspective to observe the pedicle section. Document the confirmed displacement parameters in the panel (Figure 7).</li>
	<li>Utilize the aforementioned Move/Copy function to manipulate the position of the vertebral model. Specify the displacement parameter in the left panel. Employ the Corner Rectangle tool to encompass the entirety of the vertebral body.</li>
	<li>To begin, navigate to the Features-Reference Geometry-Plane option and designate the section view as the First Reference. Modify the offset distance parameter accordingly to relocate the newly created plane to the anterior third of the vertebral body.</li>
	<li>Proceed to generate a Sketch on the aforementioned plane and draw a Point at the midpoint of the vertebral body, signifying the termination point of the puncture.</li>
	<li>Use the Extruded Cut function to perform the cutting of the model. Designate the rectangular sketch generated as the Selected Contours.</li>
	<li>Make adjustments to both the direction and depth to divide the vertebral body model into two halves, namely the vertebral body half and the lamina half (Figure 8A). Save the engineering files in SLDPRT format, specifically as part of the process.</li>
	<li>Open the file containing the vertebral body part, followed by the creation of a sketch based on the section plane. Use the Convert Entities function to convert the left pedicle projection into a curve sketch.</li>
	<li>Repeat the above procedure for the right pedicle projection, resulting in the acquisition of another curve sketch. Employ the Filled Surface function to transform the curve sketches into surfaces, with the left and right pedicle projection curve sketches serving as the boundary (Figure 8B).</li>
	<li>Display the resulting surface after the vertebra has been concealed. Select the Lofted Boss/Base function on the Features panel.</li>
	<li>The superior positioning of the left pedicle surface, with the designation of the puncture endpoint as Profiles, will yield a conical structure delineating the paths for pedicle puncture. Use the left side as a reference for illustrative purposes, with the same process to be replicated on the right side.</li>
	<li>Use the Scale function to magnify the bilateral conical structure, with the centroid serving as the scaling center point and a scale factor of 2. Employ the Move/Copy Body function to individually relocate the conical structures.</li>
	<li>Within the Mate Setting panel interface, select the apex of the structure and the puncture end point, with the matching mode set as Coincident. Eliminate the vertebral body subsequently using the Delete/Keep Body function (Figure 9A).</li>
	<li>The biconical structure is a compilation of bilateral pedicle puncture paths, saved in SLDPRT format. Employ the Insert Part function to reassemble the lamina part and the vertebral body part using the pedicle puncture set. Simply press the OK button to automatically align the insert position of the part with the origin (Figure 9B).</li>
	<li>Employ the Combine Body function for executing Boolean operations on various components. Through the process of subtracting the puncture set from one half of the laminae while retaining all laminae components, the subsequent analysis indicates that the ideal bone puncture region includes regions 1, 4, and 7 on the left side (Figure 9C).</li>
</ol>

Enhancing Pedicle Puncture Precision with 3D Modeling and a Nine-Grid Method

<ol>
	<li>Wenhao, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+percutaneous+kyphoplasty+with+high-viscosity+and+low-viscosity+bone+cement+for+treatment+of+osteoporotic+vertebral+compression+fractures:+a+retrospective+study.">A comparison of percutaneous kyphoplasty with high-viscosity and low-viscosity bone cement for treatment of osteoporotic vertebral compression fractures: a retrospective study.</a> Geriatr Orthop Surg Rehabil. 13, 21514593221119625 (2022).</li><li>Xuebiao, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CT+features+and+risk+factors+of+pulmonary+cement+embolism+after+vertebroplasty+or+kyphoplasty+in+patients+with+vertebral+compression+fracture:+a+retrospective+cohort+study.">CT features and risk factors of pulmonary cement embolism after vertebroplasty or kyphoplasty in patients with vertebral compression fracture: a retrospective cohort study.</a> Quant Imaging Med Surg. 13 (4), 2397-2407 (2023).</li><li>Liehua, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+study+on+the+puncture+method+of+extrapedicular+infiltration+anesthesia+applied+during+lumbar+percutaneous+vertebroplasty+or+percutaneous+kyphoplasty.">A study on the puncture method of extrapedicular infiltration anesthesia applied during lumbar percutaneous vertebroplasty or percutaneous kyphoplasty.</a> Medicine (Baltimore). 98 (33), e16792 (2019).</li><li>Lo Bianco, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interventional+pain+procedures:+a+narrative+review+focusing+on+safety+and+complications.+PART+2+Interventional+procedures+for+back+pain.">Interventional pain procedures: a narrative review focusing on safety and complications. PART 2 Interventional procedures for back pain.</a> J Pain Res. 16, 761-772 (2023).</li><li>Jie, W., Qiang, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beware+of+Brucella+spondylitis+following+vertebroplasty:+an+unusual+case+of+osteoporotic+vertebral+compression+fracture.">Beware of Brucella spondylitis following vertebroplasty: an unusual case of osteoporotic vertebral compression fracture.</a> Infect Drug Resist. 15, 2565-2572 (2022).</li><li>Xinqiang, H., Yongzhen, Z., Zhu, W., Mengpeng, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Case+report:+Cement+entrapped+in+the+inferior+vena+cava+filter+after+pedicle+screw+augmentation.">Case report: Cement entrapped in the inferior vena cava filter after pedicle screw augmentation.</a> Front Cardiovasc Med. 9, 892025 (2022).</li><li>Saracen, A., Kotwica, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complications+of+percutaneous+vertebroplasty:+An+analysis+of+1100+procedures+performed+in+616+patients.">Complications of percutaneous vertebroplasty: An analysis of 1100 procedures performed in 616 patients.</a> Medicine (Baltimore). 95 (24), e3850 (2016).</li><li>Peilun, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+&amp;#34;three-dimensional-printed+individual+guide+template-assisted+percutaneous+vertebroplasty&amp;#34;+for+osteoporotic+vertebral+compression+fracture:+a+prospective,+controlled+study.">A novel &amp;#34;three-dimensional-printed individual guide template-assisted percutaneous vertebroplasty&amp;#34; for osteoporotic vertebral compression fracture: a prospective, controlled study.</a> J Orthop Surg Res. 16 (1), 326 (2021).</li><li>Jiashen, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+sarcopenia+and+sagittal+parameters+on+the+residual+back+pain+after+percutaneous+vertebroplasty+in+patients+with+osteoporotic+vertebral+compression+fracture.">Impact of sarcopenia and sagittal parameters on the residual back pain after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fracture.</a> J Orthop Surg Res. 17 (1), 111 (2022).</li><li>Songfeng, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+of+percutaneous+vertebroplasty+for+the+relief+of+osteoblastic+spinal+metastasis+pain.">Efficacy of percutaneous vertebroplasty for the relief of osteoblastic spinal metastasis pain.</a> Exp Ther Med. 22 (1), 727 (2021).</li><li>Ruszat, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photoselective+vaporization+of+the+prostate:+subgroup+analysis+of+men+with+refractory+urinary+retention.">Photoselective vaporization of the prostate: subgroup analysis of men with refractory urinary retention.</a> Eur Urol. 50 (5), 1040-1049 (2006).</li><li>Junchuan, X., Jisheng, L., Jian, L., Yong, Y., Qi, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=&amp;#34;Targeted+percutaneous+vertebroplasty&amp;#34;+versus+traditional+percutaneous+vertebroplasty+for+osteoporotic+vertebral+compression+fracture.">&amp;#34;Targeted percutaneous vertebroplasty&amp;#34; versus traditional percutaneous vertebroplasty for osteoporotic vertebral compression fracture.</a> Surg Innov. 26 (5), 551-559 (2019).</li></ol>

The authors have no conflict of interest regarding any drugs, materials, or devices described in this study.

Percutaneous vertebroplasty (PVP) has demonstrated favorable clinical efficacy in managing painful osteoporotic vertebral compression fractures (OVCF)9. The utilization of precise percutaneous pedicle puncture technology by surgeons plays a crucial role in determining the optimal insertion point, direction, and depth of the puncture needle, thereby significantly reducing the occurrence of complications10. Currently, C-arm X-ray machines are widely employed in the domestic a...

Osteoporotic vertebral compression fracture (OVCF) is the most prevalent type of fracture among osteoporotic fractures and poses a significant clinical concern in contemporary healthcare1. According to current guidelines, percutaneous vertebroplasty is recognized as one of the most efficacious minimally invasive treatment modalities for OVCF2. The predominant method for performing percutaneous vertebroplasty (PVP) involves the pedicle puncture approach, which encompasses three key parameters: the identification of the bone puncture entry point, puncture angle, and puncture depth. Of these parameters, the selection of the bone puncture entry point is considered the most crucial.
Currently, C-arm X-ray machines are widely employed in the domestic and international practice of traditional PVP surgery to facilitate the adjustment of the surgical path of the puncture needle. The crucial aspect lies in identifying the &#34;ideal bone puncture point,&#34; which is conventionally situated at the projection &#34;left 10 points, right 2 points&#34; of the pedicle in the lumbar spine (Figure 1A)3. Despite their experience, even seasoned surgeons may make mistakes when determining appropriate puncture points based solely on personal experience. This can lead to puncture-related complications such as cement leakage into surrounding tissues, nerve root injury, and intra-spinal hematoma4,5,6. Additionally, nearly half of patients experience local complications from traditional PVP, with 95% of these complications attributed to cement leakage into surrounding tissue or embolization of paravertebral veins7. Our preliminary research found that the actual PVP bone puncture points in the lumbar spine are not always located at the ideal pedicle projection &#34;left 10 points and right 2 points&#34;8. Some actual puncture points can also achieve satisfactory puncture results near the &#34;ideal bone puncture point,&#34; which does not affect surgical safety and accuracy.
Based on the above assumptions, we propose, for the first time, the concept of the &#34;ideal bone puncture region&#34; for PVP in the lumbar spine and divide the projection of the pedicle into a &#34;Nine-grid Area&#34;. The concept of the ideal bone puncture region pertains to specific anatomical regions where the puncture entry point can successfully and securely reach the puncture ideal endpoint through the pedicle.The term &#34;Nine-grid Area Division Method&#34; refers to a technique in the X-ray anteroposterior image whereby the longest and shortest diameters of the pedicle projection are divided into three equal parts, resulting in the division of the area into nine regions (Figure 1B). These regions are sequentially numbered from 1 to 9, progressing from the outermost to the innermost and from top to bottom. Using the X-ray projection of the lumbar pedicle as an anatomical marker, we establish the &#34;ideal bone puncture region&#34; for PVP through the &#34;Nine-grid Area Division Method&#34; instead of being confined to a single point. We use computer simulation to explore a safe puncture path during the puncture process.
Hence, we suggest the implementation of the &#34;Nine-grid Area Division Method&#34; as a potential method for enhancing the convenience, efficiency, and safety of auxiliary puncture techniques in PVP surgery, with the aim of enhancing procedural accuracy and minimizing puncture-related complications. It is important to note that this study presents a theoretical approach that requires validation through extensive research to ascertain its efficacy and safety.

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			<td>Computer tomography&#160;</td>
			<td>Company GE</td>
			<td></td>
			<td>machine</td>
		</tr>
		<tr>
			<td>Geomagic Wrap (3-D reverse engineering production software)</td>
			<td>Oqton software</td>
			<td></td>
			<td>software</td>
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			<td>Magnetic resonance image machine</td>
			<td>Company GE</td>
			<td></td>
			<td>machine</td>
		</tr>
		<tr>
			<td>&#160;Materialise Interactive Medical Image Control System (medical imaging processing software)</td>
			<td>Materialise Company</td>
			<td></td>
			<td>software</td>
		</tr>
		<tr>
			<td>Solidworks (3-D modeling design software)</td>
			<td>Dassault Syst&#232;mes&#160;-&#160;SolidWorks Corporation</td>
			<td></td>
			<td>software</td>
		</tr>
		<tr>
			<td>Spirit Level Plus</td>
			<td>IOS App store</td>
			<td></td>
			<td>gradientor</td>
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			<td>X-ray machine</td>
			<td>Company Philips</td>
			<td></td>
			<td>machine</td>
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nine-grid area division method: a new ideal bone puncture region for percutaneous vertebroplasty in lumbar spine

Percutaneous vertebroplasty (PVP) is widely recognized as an efficacious intervention for alleviating low back pain resulting from osteoporotic vertebral compression fractures. The ideal bone puncture point is conventionally situated at the projection "left 10 points, right 2 points" of the pedicle in the lumbar spine. Determining the optimal bone puncture point represents a critical and complex challenge. The accuracy of percutaneous vertebroplasty (PVP) is primarily influenced by the proficiency of the operating surgeons and the utilization of multiple fluoroscopes during the conventional procedure. Incidences of puncture-related complications have been documented globally. In an effort to enhance the precision of the surgical technique and reduce the occurrence of puncture-related complications, our team applied the "Nine-grid Area Division Method" for PVP in the lumbar spine to modify the traditional procedure. There is potential to decrease the number of puncture times, the radiation exposure dosage, and the duration of surgical procedures.
This protocol introduces the definition of the "Nine-grid Area Division Method" and describes the process of modeling target vertebrae DICOM imaging data within medical imaging processing software, simulating operations within a 3-D model, refining the 3-D model using reverse engineering production software, reconstructing the vertebral engineering model within 3-D modeling design software, and utilizing surgical data to determine safe entry regions for pedicle projection. By employing this methodology, surgeons can effectively identify appropriate puncture points with precision and ease, thereby reducing the intricacies associated with puncturing and enhancing the overall accuracy of surgical procedures.

CT imaging and digital modeling were performed in the hospital. It took 30 min to build the 3-D model from the CT images, ~10 min to polish the 3-D model in 3-D reverse engineering production software, and 15 min to reconstruct the vertebral engineering model and confirm the safe entry regions of pedicle projection in 3-D modeling design software. The ideal bone puncture region includes regions 1, 4, and 7 on the left side in this case. The notion of the ideal bone puncture region refers...

Author Spotlight: Improving Percutaneous Vertebroplasty Surgical Accuracy and Efficiency Through Advanced Puncture Techniques

Herein, we present a "Nine-grid Area Division Method" for percutaneous vertebroplasty. A patient with an L1 vertebral compression fracture was selected as a case study.

Nine-Grid Area Division Method: A New Ideal Bone Puncture Region for Percutaneous Vertebroplasty in Lumbar Spine

Percutaneous vertebroplasty (PVP) is widely recognized as an efficacious intervention for alleviating low back pain resulting from osteoporotic vertebral ...

nine-grid-area-division-method-new-ideal-bone-puncture-region-for

Research

JoVE Journal

Medicine

158 Views.  Capital Medical University. Herein, we present a "Nine-grid Area Division Method" for percutaneous vertebroplasty. A patient with an L1 vertebral compression fracture was selected as a case study.

Video: Author Spotlight: Improving Percutaneous Vertebroplasty Surgical Accuracy and Efficiency Through Advanced Puncture Techniques

An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation

The study of breast cancer dormancy in the bone marrow is an exceptionally difficult undertaking due to the complexity of the interactions of dormant cells with their microenvironment, their rarity and the overwhelming excess of hematopoietic cells. Towards this end, we developed an in vitro 2D clonogenic model of dormancy of estrogen-sensitive breast cancer cells in the bone marrow. The model consists of a few key elements necessary for dormancy. These include 1) the use of estrogen sensitive breast cancer cells, which are the type likely to remain dormant for extended periods, 2) incubation of cells at clonogenic density, where the structural interaction of each cell is primarily with the substratum, 3) fibronectin, a key structural element of the marrow and 4) FGF-2, a growth factor abundantly synthesized by bone marrow stromal cells and heavily deposited in the extracellular matrix. Cells incubated with FGF-2 form dormant clones after 6 days, which consist of 12 or less cells that have a distinct flat appearance, are significantly larger and more spread out than growing cells and have large cytoplasm to nucleus ratios. In contrast, cells incubated without FGF-2 form primarily growing colonies consisting of >30 relatively small cells. Perturbations of the system with antibodies, inhibitors, peptides or nucleic acids on day 3 after incubation can significantly affect various phenotypic and molecular aspects of the dormant cells at 6 days and can be used to assess the roles of membrane-localized or intracellular molecules, factors or signaling pathways on the dormant state or survival of dormant cells. While recognizing the in vitro nature of the assay, it can function as a highly useful tool to glean significant information about the molecular mechanisms necessary for establishment and survival of dormant cells. This data can be used to generate hypotheses to be tested in vivo models.

An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation

We developed an in vitro model of dormancy in the bone marrow for estrogen-sensitive breast cancer cells. The goal of this protocol is to demonstrate use of the model for the study of the molecular and cellular biology of dormancy and for generation of hypotheses for subsequent testing in vivo.

The study of breast cancer dormancy in the bone marrow is an exceptionally difficult undertaking due to the complexity of the interactions of dormant ...

Tissue Characterization after a New Disaggregation Method for Skin Micro-Grafts Generation

Several new methods have been developed in the field of biotechnology to obtain autologous cellular suspensions during surgery, in order to provide one step treatments for acute and chronic skin lesions. Moreover, the management of chronic but also acute wounds resulting from trauma, diabetes, infections and other causes, remains challenging. In this study we describe a new method to create autologous micro-grafts from cutaneous tissue of a single patient and their clinical application. Moreover, in vitro biological characterization of cutaneous tissue derived from skin, de-epidermized dermis (Ded) and dermis of multi-organ and/or multi-tissue donors was also performed. All tissues were disaggregated by this new protocol, allowing us to obtain viable micro-grafts. In particular, we reported that this innovative protocol is able to create bio-complexes composed by autologous micro-grafts and collagen sponges ready to be applied on skin lesions. The clinical application of autologous bio-complexes on a leg lesion was also reported, showing an improvement of both re-epitalization process and softness of the lesion. Additionally, our in vitro model showed that cell viability after mechanical disaggregation with this system is maintained over time for up to seven (7) days of culture. We also observed, by flow cytometry analysis, that the pool of cells obtained from disaggregation is composed of several cell types, including mesenchymal stem cells, that exert a key role in the processes of tissue regeneration and repair, for their high regenerative potential. Finally, we demonstrated in vitro that this procedure maintains the sterility of micro-grafts when cultured in Agar dishes. In summary, we conclude that this new regenerative approach can be a promising tool for clinicians to obtain in one step viable, sterile and ready to use micro-grafts that can be applied alone or in combination with most common biological scaffolds.

The protocol describes a new method to disaggregate human tissues and to create autologous micro-grafts that, combined with collagen sponges, give rise to human bio-complexes ready to use in the treatment of skin lesions. Further, this system preserves cell viability of micro-grafts at different times after mechanical disaggregation.

Several new methods have been developed in the field of biotechnology to obtain autologous cellular suspensions during surgery, in order to provide one ...

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Pedicle screw fixation is the gold standard for the treatment of spinal diseases. However, many studies have reported the issue of loosening pedicle screws after spinal surgery, which is a serious concern. To address this problem, diverse types of pedicle screws have been examined to identify those with good fixation strength and osseointegration in spine bone. The porcine spine is a good alternative for the human spine in the evaluation of pedicle screws due to the anatomical size, mechanical characteristics, and cost. Although several studies have reported that pedicle screws are efficient in the porcine model, no study has described detailed protocols for the evaluation of a pedicle screw using the porcine model. Here, we describe a detailed method for evaluating transpedicular screws using an in vivo porcine lumbar spine model. The technical details for anesthesia, spine surgery, and harvest provided here will facilitate with the evaluation of the transpedicular screw fixation model.

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Here, we introduce a method to evaluate transpedicular screws by using an in vivo porcine lumbar spine model.

Pedicle screw fixation is the gold standard for the treatment of spinal diseases. However, many studies have reported the issue of loosening pedicle ...

Surgical Angiogenesis in Porcine Tibial Allotransplantation: A New Large Animal Bone Vascularized Composite Allotransplantation Model

Segmental bone loss resulting from trauma, infection malignancy and congenital anomaly remains a major reconstructive challenge. Current therapeutic options have significant risk of failure and substantial morbidity.
Use of bone vascularized composite allotransplantation (VCA) would offer both a close match of resected bone size and shape and the healing and remodeling potential of living bone. At present, life-long drug immunosuppression (IS) is required. Organ toxicity, opportunistic infection and neoplasm risks are of concern to treat such non-lethal indications.
We have previously demonstrated that bone and joint VCA viability may be maintained in rats and rabbits without the need of long-term-immunosuppression by implantation of recipient derived vessels within the VCA. It generates an autogenous, neoangiogenic circulation with measurable flow and active bone remodeling, requiring only 2 weeks of IS. As small animals differ from man substantially in anatomy, bone physiology and immunology, we have developed a porcine bone VCA model to evaluate this technique before clinical application is undertaken. Miniature swine are currently widely used for allotransplantation research, given their immunologic, anatomic, physiologic and size similarities to man. Here, we describe a new porcine orthotopic tibial bone VCA model to test the role of autogenous surgical angiogenesis to maintain VCA viability.
The model reconstructs segmental tibial bone defects using size- and shape-matched allogeneic tibial bone segments, transplanted across a major swine leukocyte antigen (SLA) mismatch in Yucatan miniature swine. Nutrient vessel repair and implantation of recipient derived autogenous vessels into the medullary canal of allogeneic tibial bone segments is performed in combination with simultaneous short-term IS. This permits a neoangiogenic autogenous circulation to develop from the implanted tissue, maintaining flow through the allogeneic nutrient vessels for a short time. Once established, the new autogenous circulation maintains bone viability following cessation of drug therapy and subsequent nutrient vessel thrombosis.

Currently any kind of vascularized composite allotransplantation depends on long-term-immunosuppression, difficult to support for non-life-critical indications. We present a new porcine tibial VCA model that can be used to study bone VCA and demonstrate the use of surgical angiogenesis to maintain bone viability without the need of long-term immune-modulation.

Segmental bone loss resulting from trauma, infection malignancy and congenital anomaly remains a major reconstructive challenge. Current therapeutic ...

A Mobile Outside-in Technique of Transforaminal Lumbar Endoscopy for Lumbar Disc Herniations

Percutaneous endoscopic transforaminal lumbar discectomy (PETLD) has now become a standard of care for the management of lumbar disc disease. There are two techniques for the introduction of a working cannula with respect to disc&#8212;outside-in and inside-out. The aim of this prospective study is to describe the technical aspects of a novel mobile outside-in method in dealing with different types of disc prolapse. A total of 184 consecutive patients with unilateral lower limb radiculopathy due to lumbar disc prolapse were operated on with the mobile outside-in technique of PETLD. Their clinical outcomes were evaluated based on the type of disc prolapse they had, a visual analog scale (VAS) leg pain score, the Oswestry Disability Index (ODI), and the Macnab criteria. The completeness of the decompression was documented with a postoperative magnetic resonance imaging. The mean age of the patients was 50 &#177; 16 years and the male/female ratio was 2:1. The mean follow-up was 19 &#177; 6 months. A total of 190 lumbar levels were operated on (L1&#8211;L2: n = 4, L2&#8211;L3: n = 17, L3&#8211;L4: n = 27, L4&#8211;5: n = 123, and L5&#8211;S1: n = 19). Divided into types, the patient distribution was central: n = 14, paracentral: n = 74, foraminal: n = 28, far lateral: n = 13, superior-migrated: n = 8, inferior migrated: n = 38, and high canal compromise: n = 9. The mean operative time was 35 &#177; 12 (25 - 56) min and the mean hospital stay was 1.2 &#177; 0.5 (1&#8211;3) days. The VAS score for leg pain improved from 7.5 &#177; 1 to 1.7 &#177; 0.9. The ODI improved from 70 &#177; 8.3 to 23 &#177; 5. According to the Macnab criteria, 75 patients (40.8%) had excellent results, 104 patients (56.5%) had good results, and 5 patients (2.7%) had fair results. Recurrence (including early and late) was seen in 15 out of the 190 levels that were operated on (7.89%). This article presents a novel outside-in approach that relies on a precise landing within the foramen in a mobile manner and does not solely depend upon the enlargement of the foramen. It is more versatile in application and useful in the management of all types of disc prolapse, even in severe canal compromise and high migration.

Here we present a protocol of a novel outside-in technique of transforaminal endoscopic discectomy for lumbar disc herniations. The technical aspects of the technique, the wide indications of use, and the results of the treatment in 184 patients are described in detail.

Percutaneous endoscopic transforaminal lumbar discectomy (PETLD) has now become a standard of care for the management of lumbar disc disease. There are ...

An Enzyme-free Method for Isolation and Expansion of Human Adipose-derived Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are a population of multipotent cells that can be isolated from various adult and fetal tissues, including adipose tissue. As a clinically relevant cell type, optimal methods are needed to isolate and expand these cells in vitro. Most methods to isolate adipose-derived MSCs (ADSCs) rely on harsh enzymes, such as collagenase, to digest the adipose tissue. However, while effective at breaking down the adipose tissue and yielding a high ADSC recovery, these enzymes are expensive and can have detrimental effect on the ADSCs &#8212; including the risks of using xenogeneic components in clinical applications. This protocol details a method to isolate ADSCs from fresh lipoaspirate and abdominoplasty samples without enzymes. Briefly, this method relies on mechanical disassociation of any bulk tissue followed by an explant-type culture system. The ADSCs are permitted to migrate out of tissue and onto the tissue culture plate, after which the ADSCs can be cultured and expanded in vitro for any number of research and/or clinical applications.

This protocol provides an enzyme-free method for isolating mesenchymal stem cells from abdominoplasty and lipoaspirate samples using an explant method. The absence of harsh enzymes or centrifugation steps provides for clinically relevant stem cells that can be used for studies in vitro or transferred back to the clinic.

Mesenchymal stem cells (MSCs) are a population of multipotent cells that can be isolated from various adult and fetal tissues, including adipose tissue. ...

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty (PVP)

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The accuracy of PVP mainly depends on the surgeons&#39; experience and multiple fluoroscopes during a traditional procedure. Puncture related complications were reported all over the world. To make the surgical procedure more precise and decrease the rate of puncture-related complications, our team applied a three-dimensional printing guide template to PVP to modify the traditional procedure. This protocol introduces how to model target vertebrae DICOM imaging data into three-dimensions in the software, how to simulate operation in this 3-D model, and how to use all of the surgical data to reconstruct a patient specific template for application. Using this template, surgeons can identify suitable puncture points accurately to improve the accuracy of the operation. The whole protocol includes: 1) diagnosis of the osteoporotic vertebral compression fracture; 2) acquisition of CT imaging of the target vertebra; 3) simulation of the operation in the software; 4) design and fabrication of the 3-D printing guide template; and 5) application of the template into an operation procedure.

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty PVP

Herein, we present a three-dimensional printing guide template for percutaneous vertebraplasty. A patient with a T11 vertebral compression fracture was selected as a case study.

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The ...

Posterior Approach for Debridement of the Psoas Abscess

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior approach to the spine was performed to ensure that the anterior longitudinal ligament and the psoas muscle could be visualized. All the abdominal organs were removed. Subsequently, a posterior approach was performed to remove the paraspinal muscles from L1&#8211;L5. The transverse processes, pars interarticularis and lamina of L1&#8211;L5 were identified. The exiting nerve root was identified between the transverse processes and followed into the substance of the psoas muscle. Using the anterior and posterior approach, the lumbar plexus was isolated from the substance of the psoas muscle. Before and after various steps of dissection, digital photographs were obtained. These images were uploaded into ImageJ and multiple measurements, including the distance between the lateral superior and inferior tip of each TP to the most lateral region of the plexus, the distance between the lateral superior and inferior tip of the TP to the lateral edge of the psoas, and the width of the lumbar plexus were recorded. The safe zone for entering the substance of the psoas muscle was defined between the lateral edge of the psoas muscle and the lateral edge of the lumbar plexus. The relationship of this interval to the tip of the transverse process at each level was measured and reported.

This is a cadaveric study investigating the landmarks for the posterior approach for irrigation and debridement of the psoas abscess. The interval between the transverse processes (TP) was used to access the substance of the psoas muscle.

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior ...

Utilizing Percutaneous Ventricular Assist Devices in Acute Myocardial Infarction Complicated by Cardiogenic Shock

Cardiogenic shock is defined as persistent hypotension, accompanied by evidence of end organ hypo-perfusion. Percutaneous ventricular assist devices (PVADs) are used for the treatment of cardiogenic shock in an effort to improve hemodynamics. Impella is currently the most common PVAD and actively pumps blood from the left ventricle into the aorta. PVADs unload the left ventricle, increase cardiac output and improve coronary perfusion. PVADs are typically placed in the cardiac catheterization laboratory under fluoroscopic guidance via the femoral artery when feasible. In cases of severe peripheral arterial disease, PVADs can be implanted through an alternative access. In this article, we summarize the mechanism of action of PVAD and the data supporting their use in the treatment of cardiogenic shock.

Percutaneous ventricular assist devices are increasingly being utilized in patients with acute myocardial infarction and cardiogenic shock. Herein, we discuss the mechanism of action and hemodynamic effects of such devices. We also review algorithms and best practices for the implantation, management and weaning of these complex devices.

Cardiogenic shock is defined as persistent hypotension, accompanied by evidence of end organ hypo-perfusion. Percutaneous ventricular assist devices ...

A Two-Step Method for Percutaneous Transhepatic Choledochoscopic Lithotomy

Intrahepatic and extrahepatic choledocholithiasis is a challenge in the field of biliary surgery. We present our experience using a two-step percutaneous transhepatic choledochoscopic lithotomy (PTCSL) procedure to treat challenging biliary stones. We retrospectively reviewed 81 patients with intrahepatic and extrahepatic choledocholithiasis treated using this two-step PTCSL from January 2013 to January 2020, including 40 males and 41 females, with an average age of 66 years. In contrast to traditional percutaneous transhepatic cholangioscopy (PTCS), a channel was established directly through a 16F Amplatz sheath, and the stone in the channel was removed with the aid of a nephroscope. The clinical efficacy and complications of all patients were analyzed. Eighty-one patients (81/81, 100%) had their biliary stones successfully removed; 62/81 patients (76.5%) had biliary stones completely removed after the first operation; 17/81 patients (21%) underwent a second operation; 2/81 patients (2.5%) needed a third operation to completely remove the stones. The incidence of severe bleeding during the operation was 0%, and there were no deaths. The use of the two-step PTCSL method is safe and efficacious, and contributes to a better prognosis of intrahepatic and extrahepatic choledocholithiasis.

This "two-step method" significantly improved the success rate of percutaneous transhepatic choledochoscopy and achieved a better prognosis of intrahepatic and extrahepatic choledocholithiasis.

Intrahepatic and extrahepatic choledocholithiasis is a challenge in the field of biliary surgery. We present our experience using a two-step percutaneous ...