The protocol follows the guidelines of the Ethics Committee of the Third Hospital of Hebei Medical University. Informed consent was obtained from the patients for including them and the data generated as a part of this study.
1. Pre-operative preparation
<ol>
	<li>Select patients according to the following inclusion and exclusion criteria. For the patients undergoing the surgeries, the inclusion criteria are as follows: 1) nerve compression due to thoracolumbar kyphosis, 2) severe low back pain due to kyphosis, 3) patients with Kummell disease, 4) kyphosis deformity left over by a cured infectious disease. The exclusion criteria are as follows: 1) bone destruction due to a spinal tumor, 2) infectious diseases of the spine in the active phase.</li>
	<li>After the administration of general anesthesia with endotracheal intubation, place the patient on the operating table in the prone position.</li>
	<li>Use a C-arm to localize the lesioned segment. Mark and label the location to indicate the lesion and the adjacent upper and lower vertebral bodies and make an incision trace. Then, disinfect the surgical area with iodine and alcohol and drape with sterile sheets.</li>
</ol>
2. Lesion exposure
<ol>
	<li>Make a median dorsal incision centered on the diseased vertebra with a scalpel, covering two vertebral bodies above and below. To ensure the pedicle screw can be placed in, keep the length of the incision longer than the two vertebrae adjacent to the lesion on each side.</li>
	<li>Use a scalpel to cut the skin and subcutaneous tissue vertically along the mark. Use bipolar coagulation to stop the bleeding. Then, use an electrocoagulation electrotome to separate the latissimus dorsi and multifidus muscles along the muscle attachment points until the posterior spinous process and vertebral plate are revealed.</li>
	<li>Use osteoforceps to remove part of the facet joints of the two vertebrae above and below the lesion until the articular surface is exposed completely. Then, use the positioning needle to confirm the correct position of the pedicle screws under C-arm guidance.</li>
	<li>Choose the entry point 3 mm caudal to the junction of the transverse process in the thoracic vertebra10; the entry point of the lumbar vertebra is the intersection of the horizontal line of the transverse process&#39; midpoint and the vertical line of the superior articular process.</li>
	<li>Insert eight pedicle screws bilaterally in the upper and lower segments using a reaming probe to expand the path. Depending on the disease, insert another pedicle screw on one side of the lesioned segment. If the patient suffers from osteoporosis, use bone cement-injectable cannulated pedicle screws to strengthen the vertebral bodies.</li>
	<li>Place a temporary fixation rod opposite to the osteotomy side on the pedicle screw caps, and screw and fasten the nuts. Then, use a rongeur to excise the lesioned segment&#39;s spinous process.</li>
	<li>Next, use the laminectomy rongeur to remove the lamina adjacent to the spinous process and the inferior articular process on the osteotomy side. Following these procedures, use the rongeur to cut off the transverse process on the same side. 
	&#8203;NOTE: The removal of the rib head is needed for better exposure of the thoracic vertebrae.</li>
</ol>
3. Deformity correction
<ol>
	<li>Use a modified trephine (Figure 1) to perform the osteotomy in the surgery9,11.
	<ol>
		<li>First, insert the pedicle probe into the lesioned vertebra. Then, use a modified trephine to remove the bone by twisting the handle into the vertebra. When the top of the trephine reaches the tip of the probe, the locking instrument will restrict its movement and prevent the serrated top from injuring the anterior tissue.</li>
	</ol>
	</li>
	<li>Hold on to the trephine and probe and slowly pull them out. Collect the cancellous bone in the trephine for later use. Then, repeat the same procedure to remove the bone quickly. Sometimes, the bone may not come out with the trephine; use a nucleus pulposus clamp to remove it.</li>
	<li>By changing the angle of the probe and making sure the trephine does not injure the nerves, remove the contralateral bone, preserving the vertebral arch and part of the bone.</li>
	<li>After the removal of most of the bone roughly, use the laminectomy rongeur and nucleus pulposus clamp to remove the remaining small cancellous bone fragments and discs. Then, use a curette to scrape the upper and lower endplate cartilage. When the space is large enough to implant the titanium mesh, the osteotomy is complete.</li>
	<li>Under the isolation of the dura by the nerve dissector, use the reverse curette and osteotome to remove the posterior wall of the vertebra. Once the compression to the spinal cord is relieved, gently pull the spinal cord into a position where the titanium cage can be safely implanted. Be careful not to damage the spinal dura mater to avoid cerebrospinal fluid leakage.</li>
	<li>Remove the temporary fixation bar and change it to an orthopedic rod (pre-corrected to the proper curvature), and screw and fasten the nuts on the opposite of the osteotomy.</li>
	<li>Fill an appropriately size titanium cage with the amputated autologous bone, and then place it in the correct position to prevent forward flexion of the spine. Implant the autologous fragmented bones peripherally.</li>
	<li>Place another fixing rod with the same curvature as the rod placed previously on the osteotomy side, and screw and fasten the nuts.</li>
</ol>
4. Closing the incision
<ol>
	<li>Use a large amount of saline to flush the operative field and stop active bleeding with bipolar electrocoagulation. Then, use gelatin sponges to fill the void and insert one or two closed suction drains to prevent postoperative hematoma.</li>
	<li>Close the incision layer-by-layer and ensure that each layer is not sutured to the drains. Use interrupted suture to suture the muscle and continuous suture to close the fascia by using absorbable suture material (size 1-0 for muscle and deep fascia, size 2-0 for superficial fascia). Use a skin stapler to suture the skin.</li>
</ol>
5. Post-operative care
<ol>
	<li>Measure the blood loss through the drain by observing the blood in the drainage bottle each day. The surgeons should also evaluate hidden blood loss to make sure the patients can obtain fast recovery12. Remove the drain when the blood loss is less than 50 mL per day.</li>
	<li>Allow patients to walk with a thoracolumbosacral orthosis if no venous thromboembolism is detected by a deep vein ultrasound scan. The orthosis is usually used for more than 3 months.</li>
</ol>

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Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+treatment+evaluation+for+osteoporotic+Kummell+disease+by+modified+posterior+vertebral+column+resection:+Minimum+of+one-year+follow-up.">The treatment evaluation for osteoporotic Kummell disease by modified posterior vertebral column resection: Minimum of one-year follow-up.</a> Medical Science Monitor. 23, 606-612 (2017).</li><li>Fennell, V. S., Palejwala, S., Skoch, J., Stidd, D. A., Baaj, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Freehand+thoracic+pedicle+screw+technique+using+a+uniform+entry+point+and+sagittal+trajectory+for+all+levels:+Preliminary+clinical+experience.">Freehand thoracic pedicle screw technique using a uniform entry point and sagittal trajectory for all levels: Preliminary clinical experience.</a> Journal of Neurosurgery: Spine. 21 (5), 778-784 (2014).</li><li>Wang, 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=Comparison+of+clinical+and+radiological+improvement+between+the+modified+trephine+and+high-speed+drill+as+main+osteotomy+instrument+in+pedicle+subtraction+osteotomy.">Comparison of clinical and radiological improvement between the modified trephine and high-speed drill as main osteotomy instrument in pedicle subtraction osteotomy.</a> Medicine. 94 (45), 2027 (2015).</li><li>Li, X., Ding, W., Zhao, R., Yang, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Risk+factors+of+total+blood+loss+and+hidden+blood+loss+in+patients+with+adolescent+idiopathic+scoliosis:+A+retrospective+study.">Risk factors of total blood loss and hidden blood loss in patients with adolescent idiopathic scoliosis: A retrospective study.</a> BioMed Research International. 2022, 9305190 (2022).</li><li>Wang, 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=Unilateral+posterior+vertebral+column+resection+for+severe+thoracolumbar+kyphotic+deformity+caused+by+old+compressive+vertebrae+fracture:+A+technical+improvement.">Unilateral posterior vertebral column resection for severe thoracolumbar kyphotic deformity caused by old compressive vertebrae fracture: A technical improvement.</a> International Journal of Clinical and Experimental Medicine. 8 (3), 3579-3584 (2015).</li><li>Liu, F. Y., 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=Modified+posterior+vertebral+column+resection+for+Kummell+disease:+Case+report.">Modified posterior vertebral column resection for Kummell disease: Case report.</a> Medicine. 96 (5), 5955 (2017).</li><li>Policicchio, D., 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=Pedicled+multifidus+muscle+flap+to+treat+inaccessible+dural+tear+in+spine+surgery:+Technical+note+and+preliminary+experience.">Pedicled multifidus muscle flap to treat inaccessible dural tear in spine surgery: Technical note and preliminary experience.</a> World Neurosurgery. 145, 267-277 (2021).</li><li>Yang, C., 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=Posterior+vertebral+column+resection+in+spinal+deformity:+A+systematic+review.">Posterior vertebral column resection in spinal deformity: A systematic review.</a> European Spine Journal. 25 (8), 2368-2375 (2016).</li><li>Tang, H. Z., Xu, H., Yao, X. D., Lin, S. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-stage+posterior+vertebral+column+resection+and+internal+fixation+for+old+fracture-dislocations+of+thoracolumbar+spine:+A+case+series+and+systematic+review.">Single-stage posterior vertebral column resection and internal fixation for old fracture-dislocations of thoracolumbar spine: A case series and systematic review.</a> European Spine Journal. 25 (8), 2497-2513 (2016).</li></ol>

The authors have no conflicts of interest in this research.

The steps of placing the temporary fixation rod and the deformity correction mentioned in the protocol are the critical steps during the surgery. By preserving one side of the pedicle and loading a temporary fixation bar, stability is preserved during the osteotomy procedure. During the surgical progress of the deformity correction, the nerve roots must be protected to prevent serious postoperative neurological complications. If the surgeons are uncertain about the location of the nerve roots, the exposure of the nerve roots after removing the vertebral plate and the articular process is necessary. When removing the wall of the vertebral canal, blood loss can be huge due to the venous plexus. Although blood loss may be reduced using bipolar electrocoagulation to stop the bleeding, accompanied by gelatin sponges and brain cotton pieces layer-by-layer, the long surgery time is a big problem. The surgeons can prepare blood transfusion in advance and use an autologous blood transfusion system because of the long operation time and huge blood loss. If a dural matter tear happens during the surgery, the surgeons can use dural suture to fix the damage; a pedicled multifidus muscle flap is also useful according to previous research15. To prevent damage to the abdominal aorta or thoracic aorta, surgeons must be careful in removing the bone near the anterior longitudinal ligament. In addition, a C-arm can be used to detect the position of the pedicle probe to avoid over-insertion damage caused by the serrated top of the trephine. The cancellous bone collected by the trephine can be directly used in the titanium cage for the autologous bone graft.
The unilateral PVCR technique shortens the operation time compared to the classic PVCR as only one side of the vertebral pedicle access is required. Subsequently, the unilateral PVCR technique reduces the stimulation to the spinal cord and nerve roots. By using this approach, the contralateral vertebral pedicle and parts of the vertebra can be saved to increase the stability and bone fusion rate compared to total laminectomy. However, this technique is solely based on classic PVCR with the innovation of the tools. Therefore, similar to the original PVCR, the implant-related complications would still happen due to osteotomy16.
With the use of modified trephine, bone excision becomes easier and more controllable than the traditional use of a high-speed drill and osteotome. Surgeons with the ability of pedicle screw placement can master the refined technique quickly. The unilateral PVCR technique with the modified trephine provides a quicker way to resect and collect the bone, shortening the surgical time for surgeons to do more delicate operations. It is shown that the reconstruction of physiological curvature and the correction of spinal deformity can alleviate patients&#39; symptoms, including low back pain17. Therefore, this unilateral PVCR technique can reconstruct spinal stability and rigid fixation to achieve satisfactory treatment effects with less trauma to the patients.

Thoracolumbar kyphotic deformity is a primary or secondary disease generally caused by vertebrae fracture, vertebral body development, ankylosing spondylitis, and spinal tuberculosis1,2,3,4. Severe kyphotic deformity often induces spinal cord compression or severe low back pain. Once conservative treatment becomes ineffective, a surgical approach is necessary due to the complications caused by the deformity. However, the appropriate surgical treatment remains controversial.
The surgical approach to treat severe kyphotic deformity usually needs grade 3 or higher osteotomy5. Pedicle subtraction osteotomy (PSO) is a technique in which a three-column osteotomy can be achieved, which is reported with correction between 30&#176; and 40&#176;6. When the kyphotic deformity is more than 40&#176;, vertebral column resection is recommended, but it can shorten the spine and induce spinal cord bulk7. Partial body and disc resection (BDBO; grade 4) and posterior vertebral column resection (PVCR; grade 5) require complete interception of the anterior and middle columns of the spine, which may cause huge damage to the spine with severe neurologic complications due to spinal instability in the operation or postoperative implant settlement7,8. For general operators, the technique is hard to master, and the surgical damage is enormous for the patients. Thus, a method that is easier to perform with less damage is needed.
In this report, we introduce a refined surgical technique with a modified trephine to treat thoracolumbar kyphosis by removing the vertebral and adjacent discs unilaterally and placing a titanium mesh with autologous bone on the same side. This technique aims to minimize the damage to the patient while achieving good results. In our previous research, the refined surgical procedure showed significantly greater outcomes and reduced the damage to the spine through the preservation of the contralateral pedicle and part of the vertebral body9.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Adhesive</td>
			<td>Biatain</td>
			<td>3420</td>
			<td>12.5 cm x 12.5 cm</td>
		</tr>
		<tr>
			<td>Bipolar electrocoagulation tweezers</td>
			<td>Juan&#39;en Medical Devices Co.Ltd</td>
			<td>BZN-Q-B-S</td>
			<td>1.2 mm x 190 mm</td>
		</tr>
		<tr>
			<td>Bone wax</td>
			<td>ETHICON</td>
			<td>W810T</td>
			<td>2.5g</td>
		</tr>
		<tr>
			<td>Curette</td>
			<td>Qingniu</td>
			<td>20739.01</td>
			<td>300 x &#216;9 x 5&#176;</td>
		</tr>
		<tr>
			<td>Double jointed forceps</td>
			<td>SHINVA</td>
			<td>286920</td>
			<td>240 mm x 8 mm</td>
		</tr>
		<tr>
			<td>High frequency active electrodes</td>
			<td>ZhongBangTianCheng</td>
			<td>GD-BZ</td>
			<td>GD-BZ-J1</td>
		</tr>
		<tr>
			<td>Laminectomy rongeur</td>
			<td>Qingniu</td>
			<td>2054.03</td>
			<td>220 x 3.0 x 130&#176;</td>
		</tr>
		<tr>
			<td>Laminectomy rongeur</td>
			<td>Qingniu</td>
			<td>2058.03</td>
			<td>220 x 5.0 x 130&#176;</td>
		</tr>
		<tr>
			<td>Pedicle screw</td>
			<td>WEGO</td>
			<td>800386545</td>
			<td>6.5 mm x 45 mm</td>
		</tr>
		<tr>
			<td>Pedicle screw</td>
			<td>WEGO</td>
			<td>800386550</td>
			<td>6.5 mm x 50 mm</td>
		</tr>
		<tr>
			<td>Pituitary&#160;rongeur</td>
			<td>Qingniu</td>
			<td>2028.01</td>
			<td>220 mm x 3.0 mm</td>
		</tr>
		<tr>
			<td>Pituitary&#160;rongeur</td>
			<td>Qingniu</td>
			<td>2028.02</td>
			<td>220 mm x 3.0 mm</td>
		</tr>
		<tr>
			<td>Rod</td>
			<td>WEGO</td>
			<td>800386040</td>
			<td>5.5 mm x 500 mm</td>
		</tr>
		<tr>
			<td>Surgical drainage catheter set</td>
			<td>BAINUS MEDICAL</td>
			<td>SY-Fr16-C</td>
			<td>100-400 mL</td>
		</tr>
		<tr>
			<td>Surgical film</td>
			<td>3L</td>
			<td>SP4530</td>
			<td>45 cm x 30 cm</td>
		</tr>
		<tr>
			<td>Titanium&#160;cage</td>
			<td>WEGO</td>
			<td>9051228</td>
			<td>19 mm x 80 mm</td>
		</tr>
		<tr>
			<td>Trephine</td>
			<td>NATON MEDICAL GROUP</td>
			<td>DJD04130</td>
			<td>12 mm/10 mm</td>
		</tr>
	</tbody>
</table>

modified posterior vertebral column resection for patients with thoracolumbar kyphotic deformity

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may cause severe thoracolumbar kyphotic deformity, often accompanied by intractable low back pain or compression of the spinal cord, leading to severe neurological symptoms or even paralysis. If conservative treatment cannot relieve the symptoms or correct the deformities, surgical treatment is usually needed. For severe kyphotic deformity, reconstruction of the physiological curvature and rigid fixation determine the prognosis of the patients. Osteotomy and orthopedics are the standard procedure for deformities with severe compression of the front and middle column, but the trauma to the patients is high, with a long operation time and massive blood loss. To avoid these disadvantages, we have developed a modified technique to remove the diseased vertebra unilaterally. In this technique, we use a modified trephine to resect the vertebral columns like in the pedicle screw technique by adding a locking instrument that can restrict the trephine to lower the risk of osteotomy and shorten the surgery time and blood loss.

About 330&#176; decompression can be achieved by using the unilateral PVCR technique. The transverse process and the rib head need to be removed to make sure the abduction angle is enough to remove the contralateral bone.
By using the modified trephine, the bone of the diseased vertebrae can be removed easily by rotating it with mild stress. When the trephine is locked, one should pull out the trephine and probe together, and then a cylinder of cancellous bone can be obtained (Figure 2).
Not all patients require a pedicle screw&#160;implantation in the osteotomy segment. For some patients with mild vertebral compression and preoperative computed tomography showing there is enough space to implant a pedicle screw, the screw can be implanted on the opposite side of the osteotomy segment. The screw does not need to be taken out once it is implanted because instability can happen without screw fixation. If a patient is eligible for the implantation, it means the patient&#39;s segment that needs osteotomy has enough bones. The range of osteotomy can be reduced appropriately on the opposite side as long as it does not interfere with the osteotomy side.
In previous studies, compared to traditional PVCR, unilateral PVCR achieved a satisfactory result but reduced the operating time (174.6 min &#177; 26.7 min vs. 226.4 min &#177; 32.6 min), the blood loss (870.3 mL &#177; 92.5 mL vs. 997.4 mL &#177; 107.3 mL), and the incidence of nerve root impingement (4.3% vs. 8.7%)13. With the use of the modified trephine, we further shortened the osteotomy time and gained satisfactory treatment results11. In addition, we were able to combine the unilateral PVCR technique and modified trephine to remove the lesions and rebuild spinal stability for patients with Kummell disease (Figure 3 and Figure 4)9,14, especially for patients with kyphotic deformity and obvious nerve-oppressed symptoms.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64465/64465fig01.jpg" /> 
Figure 1: The modified trephine with the locking instrument. Use the probe to stab into the cancellous bone, and then rotate and push the trephine until it is locked. Put on the handle, and then pull out the probe and trephine together.&#160;This figure has been modified from Wang et al.11. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64465/64465fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64465/64465fig02.jpg" /> 
Figure 2: The bone removed by the trephine. Grab the handle of the probe and pull it out, and a columnar bone can be harvested.&#160;This figure has been modified from Wang et al.11. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64465/64465fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/64465/64465fig03.jpg" /> 
Figure 3: Preoperative images of the unilateral PVCR technique. Preoperative images of X-ray, computed tomography, and magnetic resonance imaging of a patient with Kummell Disease. This figure has been modified from Yang et al.9. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64465/64465fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/64465/64465fig04.jpg" /> 
Figure 4: Postoperative images of the unilateral PVCR technique. Postoperative images of X-ray and computed tomography of a patient with Kummell Disease after the treatment of modified posterior vertebral column resection.&#160;This figure has been modified from Yang et al.9. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64465/64465fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity at JoVE.com

Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity

We describe a modified technique for resecting the posterior vertebral column unilaterally based on a modified trephine for patients with thoracolumbar kyphotic deformity.

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may ...

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Nanyang Technological University

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JoVE Journal

Medicine

2.0K Views.  The Third Hospital of Hebei Medical University. We describe a modified technique for resecting the posterior vertebral column unilaterally based on a modified trephine for patients with thoracolumbar kyphotic deformity.

Video: Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity

Computerized Dynamic Posturography for Postural Control Assessment in Patients with Intermittent Claudication

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic conditions. As part of a diagnostic assessment, the early detection of postural deficits is important so that appropriate and targeted interventions can be prescribed. The Sensory Organization Test (SOT) on the EquiTest determines an individual&#39;s use of the sensory systems (somatosensory, visual, and vestibular) that are responsible for postural control. Somatosensory and visual input are altered by the calibrated sway-referenced support surface and visual surround, which move in the anterior-posterior direction in response to the individual&#39;s postural sway. This creates a conflicting sensory experience. The Motor Control Test (MCT) challenges postural control by creating unexpected postural disturbances in the form of backwards and forwards translations. The translations are graded in magnitude and the time to recover from the perturbation is computed.
Intermittent claudication, the most common symptom of peripheral arterial disease, is characterized by a cramping pain in the lower limbs and caused by muscle ischemia secondary to reduced blood flow to working muscles during physical exertion. Claudicants often display poor balance, making them susceptible to falls and activity avoidance. The Ankle Brachial Pressure Index (ABPI) is a noninvasive method for indicating the presence of peripheral arterial disease and intermittent claudication, a common symptom in the lower extremities. ABPI is measured as the highest systolic pressure from either the dorsalis pedis or posterior tibial artery divided by the highest brachial artery systolic pressure from either arm. This paper will focus on the use of computerized dynamic posturography in the assessment of balance in claudicants.

Individuals with intermittent claudication exhibit poor balance compared to healthy controls. Computerized dynamic posturography is an objective method for measuring an individual's postural responses to balance disturbances. This provides an objective reflection of the person&#x2019;s ability to respond to situations under which sensory stimuli are altered and unexpected perturbations occur.

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic ...

Assessment of Vascular Function in Patients With Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this is only partially explained by traditional CVD risk factors. Vascular dysfunction is an important non-traditional risk factor, characterized by vascular endothelial dysfunction (most commonly assessed as impaired endothelium-dependent dilation [EDD]) and stiffening of the large elastic arteries. While various techniques exist to assess EDD and large elastic artery stiffness, the most commonly used are brachial artery flow-mediated dilation (FMDBA) and aortic pulse-wave velocity (aPWV), respectively. Both of these noninvasive measures of vascular dysfunction are independent predictors of future cardiovascular events in patients with and without kidney disease. Patients with CKD demonstrate both impaired FMDBA, and increased aPWV. While the exact mechanisms by which vascular dysfunction develops in CKD are incompletely understood, increased oxidative stress and a subsequent reduction in nitric oxide (NO) bioavailability are important contributors. Cellular changes in oxidative stress can be assessed by collecting vascular endothelial cells from the antecubital vein and measuring protein expression of markers of oxidative stress using immunofluorescence. We provide here a discussion of these methods to measure FMDBA, aPWV, and vascular endothelial cell protein expression.

The degree of vascular dysfunction and contributing physiological mechanisms can be assessed in patients with chronic kidney disease by measuring brachial artery flow-mediated dilation, aortic pulse-wave velocity, and vascular endothelial cell protein expression.

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this ...

Murine Ileocolic Bowel Resection with Primary Anastomosis

Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn&#8217;s disease and colon cancer being two common examples. Despite the frequency of these procedures, a significant knowledge gap remains in describing the inherent effects of intestinal resection on host physiology and disease pathophysiology. This article provides detailed instructions for an ileocolic resection with primary end-to-end anastomosis in mice, as well as essential aspects of peri-operative care to maximize post-operative success. When followed closely, this procedure yields a 95% long-term survival rate, no failure to thrive, and minimizes post-operative complications of bowel obstruction and anastomotic leak. The technical challenges of performing the procedure in mice are a barrier to its wide spread use in research. The skills described in this article can be acquired without previous surgical experience. Once mastered, the murine ileocolic resection procedure will provide a reproducible tool for studying the effects of intestinal resection in models of human disease.

Ileocolic resection is commonly performed in several human diseases; however, little is known regarding the impact of intestinal resection on surgical illnesses. This article provides instruction on executing the procedure in mice with high success, providing a means to study the effects of ileocolic resection in models of disease.

Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn&#8217;s disease and colon cancer ...

Apical Resection Mouse Model to Study Early Mammalian Heart Regeneration

Cardiovascular disease plagues the whole world due to intensive lifestyle changes. Heart regeneration holds great promise for repairing and restoring cardiomyocytes lost due to injury and disease. In contrast to the robust cardiac regeneration of certain lower vertebrates, adult mammalian hearts typically show minimal capacity for heart regeneration and repair. However, recent studies have sparked considerable scientific interest with the finding that, between postnatal day 1 to 7 (P1 to P7), the neonatal mouse heart retains significant regenerative potential after apical resection (i.e., surgical amputation and exposure of left ventricular apex). One major controversy over this finding might be due to the diverse surgery-related procedures used in efforts to replicate or expand upon this important finding. These instructions dynamically present the materials and methodology for apical resection in a mouse model. The salient steps of this rodent survival surgery involve hypothermia anesthesia, thoracotomy, surgical amputation of heart ventricular apex, and suture and recovery of mice. The approach described could expand the application of the apical resection mouse model for cardiovascular research.

A step-by-step video protocol of apical resection is demonstrated in this study. Apical resection is a recently highlighted surgical approach in mammalian heart regeneration research. This study may promote the application of apical resection as a standard methodology in research into the mechanism underlying heart regeneration.

Cardiovascular disease plagues the whole world due to intensive lifestyle changes. Heart regeneration holds great promise for repairing and restoring ...

MRI-guided Focused Ultrasound Thalamotomy for Patients with Medically-refractory Essential Tremor

Essential tremor (ET) is the most common type of tremor in adults. While ET does not result in decreased life expectancy, the disabilities associated with ET can have a significant impact on quality of life, mood, functional activities, and socialization. Patients suffering from ET not sufficiently treated with first line medications may be eligible for alternative strategies such as deep brain stimulation, radiofrequency ablation, and MRI guided focused ultrasound (MRgFUS). High-intensity MRgFUS is an emerging modality to treat ET, its attraction for patients being that it is noninvasive and associated with short recovery time, as patients are home the day after treatment. While MRgFUS centers are still limited, it will become important for clinicians to consider MRgFUS as a treatment alternative, particularly in the case of a patient for whom open surgery is contraindicated. This article outlines the steps of patient selection, equipment setup, sonication, and post-treatment follow-up, as well as critical steps to be aware of when performing a MRgFUS procedure.

High-intensity MRI guided focused ultrasound is an emerging noninvasive technique to precisely ablate brain tissue. It has been shown to be safe and effective in treating medically-refractory essential tremor. This article describes the protocol for thalamotomy from patient selection to equipment setup to post-treatment follow-up.

Essential tremor (ET) is the most common type of tremor in adults. While ET does not result in decreased life expectancy, the disabilities associated with ...

Endoscopic Septoplasty with Limited Two-line Resection: Minimally Invasive Surgery for Septal Deviation

Endoscopic septoplasty is a surgical procedure in otolaryngology that is commonly performed to treat nasal airway obstruction caused by nasal septal deviation. It has a long history with multiple variations. In this article, a modified endoscopic septoplasty procedure using the limited two-line resection (2LoRs) technique at the posterior and inferior junction of the cartilaginous and bony septum is presented based on embryologic and anatomic knowledge of the nasal septum and the biomechanics of cartilaginous behavior. With this procedure, the quadrangular cartilage can be preserved as much as possible, which is helpful in retaining the supporting framework and rigidness of the septum. 2LoRs has been proven effective and sound for the correction of nasal septal deviation with rare complications. This modified procedure can be applied to correct the deviated nasal septum in the absence of any external nasal deformity to improve nasal patency or to improve access to the middle meatus or to the axillary region of the middle turbinate. It may also be used to expand the indications of septoplasty to children and adolescents because of its minimally invasive approach.

Endoscopic septoplasty is a time-honored surgical procedure with multiple variations. This paper focuses on a step-by-step surgical approach to perform a modified septoplasty procedure known as limited two-line resection. This surgical technique can be applied to correct a deviated nasal septum in the absence of an external nasal deformity.

Endoscopic septoplasty is a surgical procedure in otolaryngology that is commonly performed to treat nasal airway obstruction caused by nasal septal ...

Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

Patients with severe traumatic brain injury (sTBI) have difficulty knowing whether they are accurately expressing their thoughts and emotions because of disorders of consciousness, disrupted higher brain function, and verbal disturbances. As a consequence of an insufficient ability to communicate, objective evaluations are needed from family members, medical staff, and caregivers. One such evaluation is the assessment of functioning brain areas. Recently, multimodal brain imaging has been used to explore the function of damaged brain areas. [18F]-fluorodeoxyglucose positron emission tomography-computed tomography ([18F]FDG-PET/CT) is a successful tool for examining brain function. However, the assessment of brain glucose metabolism based on [18F]FDG-PET/CT is not standardized and depends on several varying parameters, as well as the patient&#39;s condition. Here, we describe a series of semiquantitative assessment protocols for a region-of-interest (ROI) image analysis using self-produced [18F]FDG tracers in patients with sTBI. The protocol focuses on screening the participants, preparing the [18F]FDG tracer in the hot lab, scheduling the acquisition of [18F]FDG-PET/CT brain images, and measuring glucose metabolism using the ROI analysis from a targeted brain area.

Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

[18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography is useful for studying glucose metabolism related to brain function. Here, we present a protocol for an [18F]FDG tracer set-up and semiquantitative assessment of the region-of-interest analysis for targeted brain areas associated with clinical manifestations in patients with severe traumatic brain injury.

Patients with severe traumatic brain injury (sTBI) have difficulty knowing whether they are accurately expressing their thoughts and emotions because of ...

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 ...

Fertility Preservation in Patients with Severe Ovarian Dysfunction

Ovarian function progressively declines during aging and in some pathophysiological conditions including karyotype abnormality, autoimmune diseases, chemo- and radiation-therapies, as well as ovarian surgeries. In unmarried women with severe ovarian dysfunction, fertility preservation is important for future pregnancies. Although oocyte cryopreservation is an established method for fertility preservation, these patients could only preserve a limited number of oocytes even after ovarian hyperstimulation, leading to repeated stimulations to ensure sufficient oocytes to guarantee future pregnancy. To solve this issue, we have recently developed a drug-free in vitro activation (IVA) procedure, which enable us to stimulate early stages of ovarian follicles to develop to the preantral follicle stage. These preantral follicles can respond to the unique protocol of gonadotropin stimulation, resulting in increased number of retrieved oocytes per ovarian stimulation for cryopreservation. The drug-free IVA comprised from the surgical approach and ovarian stimulation. We removed a part of cortex from one or both ovaries from patients under laparoscopic surgery. The ovarian cortical tissues were cut into small cubes to disrupt the Hippo signaling pathway and stimulate the development of early stage follicles. These cubes were grafted orthotropically into remaining ovaries as well as beneath the serosa of both Fallopian tubes. We have already published the surgical procedure of the drug-free IVA and the protocol of subsequent ovarian stimulation, but herein we present the details of laboratory methods required for drug-free IVA.

We present details of laboratory procedures for drug-free in vitro activation (IVA) of ovarian follicles for patients with severe ovarian dysfunction. This method could increase the number of retrievable oocytes per ovarian hyperstimulation and benefit fertility preservation for those patients.

Ovarian function progressively declines during aging and in some pathophysiological conditions including karyotype abnormality, autoimmune diseases, ...

Enema of Traditional Chinese Medicine for Patients with Severe Acute Pancreatitis

Severe acute pancreatitis (SAP) is characterized by high mortality rates, numerous complications, and extreme difficulties in treatment. A traditional Chinese medicine (TCM) enema has been widely utilized in clinical and experimental studies of SAP. It has been demonstrated to have beneficial effects in protecting pancreatic function and delaying disease progression. The procedure of TCM enema is to perfuse the Chinese medicinal liquid of raw rhubarb (Rheum officinale Baill. DaHuang) from the anus into the rectum and colon. Basic steps of the procedure include boiling the herbal solution in advance, using a disposable enema kit to assist patients in taking a left lying position, raising the patient's hip 10 cm, and carefully inserting the enema 30-35 cm into the anus, with a drip speed of 60-80 drops/min. The medicine liquid temperature should be equivalent to the patient's body temperature, typically between 37-39 &#176;C. The end of the enema operation should be slow, and Tui na (massage therapy) should be administered before extubation. The medication liquid should be kept in the rectum for more than 1 h. After issuing an enema, it is essential to observe the patient's feces and abdomen, and to evaluate the remission of abdominal signs and symptoms.

An enema is a type of traditional Chinese medicine (TCM) therapy used to treat severe acute pancreatitis (SAP). The therapy involves instilling a TCM liquid into the rectum and colon through the anus to keep the liquid in the intestine, absorbing through the intestinal mucosa. This study aims to standardize the enema procedure for SAP patients.

Severe acute pancreatitis (SAP) is characterized by high mortality rates, numerous complications, and extreme difficulties in treatment. A traditional ...