This study was supported by the Okayama Spine Group.

This study was approved by the ethics committee of Okayama Rosai Hospital (No. 305).
1. Patient history taking
<ol>
	<li>Ensure that the patient has a herniated disc that causes severe sciatica. Usually, the patient will have a history of some prodromal low back pain. They may correlate their symptoms with an episode of trauma.</li>
	<li>Ask the patient to describe their radiating leg pain, including its location. Also ask them about the activities that make it better or worse when LFS or LLDH is suspected.</li>
</ol>
2. Physical examination
<ol>
	<li>To determine the nerve level, check for the signs of the loss of sensation and weakness in the leg.</li>
	<li>Perform a range of lumbar motion tests by asking the patient to bend forward and backward.
	<ol>
		<li>Check for the induction of low back pain in the patient with a herniated disc when forward bending is done.</li>
		<li>Elevate the patient&#39;s leg in a supine position. If the angle between the bed and the leg is less than 70&#176; due to sciatica, this is a strong suggestion that the patient has a herniated disc, which means the straight leg raise (SLR) test is positive. 
		NOTE: The SLR test is very useful to distinguish between lumbar canal stenosis (SLR-) and lumbar disc herniation (SLR+).</li>
	</ol>
	</li>
	<li>Perform deep tendon reflex, and check muscle weakness in the patient.</li>
	<li>Perform the Kemp test7. Fix the patient&#39;s opposite ilium from the side being tested with one hand in a standing position. Grab the patient&#39;s shoulder with the other hand and lead the patient to extension, ipsilateral side bending, and rotation. 
	NOTE: LFS is characterized by exacerbation with foraminal narrowing caused by lumbar extension (Kemp&#39;s sign)7. If the Kemp test is positive, foraminal nerve compression by disc herniation or stenosis is likely.</li>
</ol>
3. Evaluation of radiograms (XP) and magnetic resonance imaging (MRI)
<ol>
	<li>Perform anteroposterior and lateral radiography in a standing position to check lumbar deformity and spondylolisthesis. If the patient has severe deformity, spinal fusion is indicated.</li>
	<li>Perform functional radiography in a standing position. Check the functional radiograms to confirm lumbar instability by measuring vertebral abnormal movement (Figure 1A, B). 
	NOTE: If there is severe instability that indicates more than 10&#176; or more than 3 mm slip at the L5-S1 level, L5-S1 fusion should be considered.</li>
	<li>Perform MRI to accurately assess the nerve compression site.
	<ol>
		<li>For lateral lumbar disc herniation (LLDH), take a coronal T2 weighted image to identify the location of the herniated disc (Figure 1C-E).</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63603/63603fig01.jpg" /> 
Figure 1: Preoperative radiograms and MRI. (A) Lateral extension radiogram, (B) Lateral flexion radiogram, (C) Parasagittal T2 weighted MRI image, (D) Coronal T2 weighted MRI image, (E) Axial T2 weighted MR&#160;imaging at the L5-S1. The arrow indicates FLDH. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
4. Evaluation of computed tomography (CT) and MRI-CT fusion images
<ol>
	<li>Perform CT to check if there is a calcified disc (Figure 2A, D) or foraminal osteophyte (Figure 2B, C) not by the disc.</li>
	<li>Take an MRI-CT fusion image to understand the exact 3D location of the herniated disc (Figure 3).</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/63603/63603fig02.jpg" /> 
Figure 2: Preoperative CT. (A,B) Parasagittal reconstruction CT, (C) Coronal reconstruction CT, (D) Axial CT at L5-S1. The white arrows indicate calcified FLDH; a black arrow shows an osteophyte. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig02large.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/63603/63603fig03.jpg" /> 
Figure 3: CT MRI fusion images. (A) Posterior view, (B) Posterolateral view. The white arrow indicates FLDH. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
5. Patient positioning and neuromonitoring (NM)
<ol>
	<li>Provide general&#160;anesthesia to the patient.</li>
	<li>Then, place the patient in a prone position on a carbon table.</li>
	<li>Ensure that the patient&#39;s eyes are not compressed with a special face cover. Pay attention to the bolster position not to compress the abdomen of the patient.</li>
	<li>Perform neuromonitoring using a multi-modality intraoperative monitoring system that assesses spinal cord integrity and provides a warning of potential harm to critical neural pathways (Figure 4A).Transcranial motor evoked potentials (MEPs) generate a stimulus at the motor cortex.
	<ol>
		<li>Use recording electrodes to measure the signals at predetermined peripheral upper and lower extremity muscle group sites. 
		NOTE: If neuromonitoring is used, nerve decompression is also confirmed with this. For a muscle of which the innervated nerve is decompressed adequately, the amplitude of the MCV usually increases.</li>
	</ol>
	</li>
</ol>
6. Intraoperative CT scan and spinal navigation
<ol>
	<li>Place a navigation reference frame (RF) percutaneously into the spinous process or sacroiliac joint. Obtain intraoperative CT scan images with a mobile CT scanner (Figure 4B).</li>
	<li>Transmit the CT 3D images to the navigation system automatically using a cable (Figure 4C).</li>
</ol>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/63603/63603fig04.jpg" /> 
Figure 4: Neuromonitoring, O-arm, and navigation. (A) Neuromonitoring, (B) O-arm, (C) Navigation. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
7. Navigated instrument registration
<ol>
	<li>Register the navigated pointer, dilater, and high-speed burr by tapping the tip to the RF hole manually. Then, perform the accuracy check by touching the bony surface.</li>
</ol>
8. Incision and muscle dissection
<ol>
	<li>With the help of a navigated pointer, confirm the location of the L5-S1 foraminal level by a 50-60 mm extended image from the pointer tip and mark the entry point for the skin incision (Figure 5A).</li>
	<li>Make an approximately 2 cm longitudinal skin incision, and then dissect the subcutaneous tissue, lumbar iliocostalis, and multifidus muscle along the muscle fibers.</li>
	<li>Dock the navigated first dilator at the base of the L5 transverse process using a navigation system (Figure 5B). Then, insert the sequential dilators (5.3 mm, 9.4 mm).</li>
	<li>Insert the final tube (14 mm) and fix it to the flexible arm assembly firmly (Figure 5C). Confirm the position of the tube with a navigation system and the anatomy through endoscopy.</li>
</ol>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/63603/63603fig05.jpg" /> 
Figure 5: Skin incision and sequential dilation. (A) Navigated pointer, (B) Navigation monitor, (C) Tubular retractor. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
9. Bone resection with the navigated high-speed burr
<ol>
	<li>Check the level with the navigated probe. Check the L5-S1 level with a navigated pointer in the navigation monitor.</li>
	<li>Remove the bone at the lower base of the transverse process and the lateral part of the facet joint with a navigated high-speed burr or conventional high-speed burr (Figure 6). 
	NOTE: Further surgical steps are planned according to the disc herniation or canal stenosis.</li>
	<li>In the case of canal stenosis, remove the bony element that compresses the nerve root completely. 
	CAUTION: Before using the navigated instruments, the surgeon should check the accuracy of navigation because sometimes the reference frame is moved.</li>
</ol>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/63603/63603fig06.jpg" /> 
Figure 6: Navigated high-speed burr. (A,B): Intraoperative image, (B): Navigated high-speed burr. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig06large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
10. Endoscopic disc resection
<ol>
	<li>For LLDH, identify the L5 nerve root and retract cranially by a nerve retractor. Then, remove the disc fragment using pituitary forceps carefully.</li>
	<li>In the case of LFS, widen the L5 foramen using a navigated high-speed burr under navigation guidance.</li>
	<li>Remove every compressing soft tissue and bony element by pituitary forceps and Kerrison rongeurs. Identify the L5 root by its surrounding perineural fat and vessels (Figure 7).</li>
</ol>
<img alt="Figure 7" class="xfigimg" src="/files/ftp_upload/63603/63603fig07.jpg" /> 
Figure 7: Nerve root decompression. (A) Endoscope image; identifying and decompressing the L5 root (white arrow); the inter-vertebral foramen is widened by burring down the osteophytes with the help of a navigated burr. (B) Navigation monitor; during operation, the surgeons can view the one monitor indicating four pieces of information simultaneously: the surgical field, intraoperative neuromonitoring, intraoperative navigation, and microendoscope view. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig07large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
11. Skin closure
<ol>
	<li>After irrigation with saline water to remove the debris, place a wound suction tube at L5-S1.</li>
	<li>Then, close the skin with an absorbable suture.</li>
	<li>Postoperatively, remove the drain after 48 h. 
	NOTE: Postoperative images are shown in Figure 8.</li>
</ol>
<img alt="Figure 8" class="xfigimg" src="/files/ftp_upload/63603/63603fig08.jpg" /> 
Figure 8: Postoperative images. (A) Axial CT image at L5-S1, (B) Parasagittal reconstruction CT, (C) Axial T2 weighted MR&#160;imaging&#160;at L5-S1. The white arrows indicate the decompression area. <a href="https://www.jove.com/files/ftp_upload/63603/63603fig08large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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The authors declare that there are no conflicts of interest.

L5 radicular symptoms are caused mainly by L4-L5 disc herniation or stenosis. These symptoms may also occur due to L5 lumbar foraminal stenosis or L5-S1 lateral lumbar disc herniation (LLDH)9. Of all the symptomatic lumbar disc herniations, L5-S1 FLDH accounts for approximately 3%10. For L5-S1 foraminal lesions, a posterolateral or transforaminal approach is recommended. For this approach, there are three main techniques, such as the microscopic, tube with endoscopic, and f...

Diagnosis and surgeries for lumbar foraminal stenosis (LFS) and lumbar lateral disc herniation (LLDH) at the L5-S1 level are challenging for spine surgeons because of this level&#39;s unique structure1. The iliac crest, broad L5 transverse process (TP), small space between the sacral ala and the L5 TP, and osteophytes make the operating window very narrow2. If the bony resection is not enough, inadequate decompression to the L5 nerve root may lead to residual symptoms. Massive bony removal causes postoperative instability. These issues limit surgeons&#39; competencies with foraminal/extraforaminal L5 root decompression. Several reports have shown good results with minimally invasive spine surgeries, such as microscopic or endoscopic procedures in this area to decompress the L5 nerve root3,4. Recently, the use of navigation for foraminal decompression of the L5 root has been reported with good surgical outcomes5.
Fully endoscopic discectomy is becoming popular for removing lateral lumbar disc herniation6. Furthermore, microendoscopic procedures in combination with navigation can help the surgeon to decompress the L5 root with precision2. Usually, these techniques require intraoperative C-arm usage. The goal of this method is to decompress the L5 root precisely with minimum bony resection without a C-arm.
The indications for this technique are extraforaminal lumbar disc herniation and herniation/stenosis of the lateral half of the foraminal lumbar disc. The contraindications are herniation/stenosis of the medial one-third of the foraminal lumbar disc because the scope cannot reach the targeted area2.

<table><tbody><tr><td>1488 HD 3-Chip camera system</td><td>Stryker</td><td>1000902487</td><td></td></tr><tr><td>16mm Endoscope Attachment, Sterile</td><td>Medtronic</td><td>9560160</td><td></td></tr><tr><td>18mm Endoscope Attachment, Sterile</td><td>Medtronic</td><td>9560180</td><td></td></tr><tr><td>4K 32&quot; surgical display</td><td>Stryker</td><td>0240-031-050</td><td></td></tr><tr><td>Adjustable hinged operating carbon table</td><td>Mizuho OSI</td><td>6988A-PV-ACP</td><td>OSI Axis Jackson table</td></tr><tr><td>L10 AIM light source</td><td>Stryker</td><td>1000902487</td><td></td></tr><tr><td>METRx MED System Endoscope, Long</td><td>Medtronic</td><td>9560102</td><td></td></tr><tr><td>METRx MED System Reusable Endoscope</td><td>Medtronic</td><td>9560101</td><td>Metrx</td></tr><tr><td>METRx MED System Reusable Endoscope</td><td>Medtronic</td><td>9560101 M</td><td></td></tr><tr><td>METRx MED System Reusable Endoscope, Long</td><td>Medtronic</td><td>9560102</td><td></td></tr><tr><td>Navigated high speed bur</td><td>Medtronic</td><td>EM200N</td><td>Stelth&amp;nbsp;</td></tr><tr><td>Navigated passive pointer</td><td>Medtronic</td><td>960-559</td><td></td></tr><tr><td>NIM Eclipse system</td><td>Medtronic</td><td>ECLC</td><td>Neuromonitouring</td></tr><tr><td>O-arm</td><td>Medtronic</td><td>224ABBZX00042000</td><td>Intraoperative CT</td></tr><tr><td>Stealth station navigation system Spine 7&lt;sup&gt;R&lt;/sup&gt;</td><td>Medtronic</td><td>9733990</td><td>Navigation</td></tr><tr><td>Surgical Carts</td><td>Stryker</td><td>F-NSK-006-00</td><td></td></tr><tr><td>Tubular Retractor, 16mm</td><td>Medtronic</td><td>955-524</td><td></td></tr><tr><td>Tubular Retractor, 16mm, Long</td><td>Medtronic</td><td>9560216</td><td></td></tr><tr><td>Tubular Retractor, 18mm</td><td>Medtronic</td><td>9560118</td><td></td></tr><tr><td>Tubular Retractor, 18mm, Long</td><td>Medtronic</td><td>9560218</td><td></td></tr></tbody></table>

transtubular endoscopic posterolateral decompression for l5-s1 lumbar lateral disc herniation

We report a novel technique for C-arm free transtubular L5 nerve decompression under CT-based navigation to reduce the radiation hazard. This procedure is performed under general anesthesia and neuromonitoring. The patient is placed in a prone position on an operating carbon table. A navigation reference frame is placed percutaneously into the contralateral sacroiliac joint or spinous process. Then, CT scan images are obtained. After instrument registration, the L5-S1 foraminal level is confirmed with a navigated probe, and the entry point is marked. Using an approximately 2 cm skin incision, the subcutaneous tissue and muscles are dissected. The navigated first dilator is aimed at the L5-S1 Kambin&#39;s triangle, and sequential dilation is performed. The 18 mm tube is used and fixed to the frame. The bone around the Kambin&#39;s triangle is removed with a navigated burr. For lateral disc herniation, the L5 nerve root is identified and retracted, and the disc fragment is removed. The navigation-guided tubular endoscopic decompression is an effective procedure. There is no radiation hazard to the surgeon or the operating room staff.

Eight cases (four men, four women) underwent surgery using this new technique. The average age was 72.0 years, and the average follow-up period was 1.5 years. There were five patients with L5/S1 foraminal stenosis, two patients with L5/S foraminal disc herniation, and one patient with L3/4 foraminal disc herniation. We could perform all surgeries without a C-arm. The average surgical time and blood loss were 143 min &#177; 14 min and 134 &#177; 18 mL, respectively.
The average recovery percent...

Watch this Scientific Journal Video about Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation at JoVE.com

Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation

Presented here is a novel technique of C-arm free transtubular posterolateral decompression for lumbar foraminal stenosis and lateral disc herniation under O-arm navigation.

We report a novel technique for C-arm free transtubular L5 nerve decompression under CT-based navigation to reduce the radiation hazard. This procedure is ...

transtubular-endoscopic-posterolateral-decompression-for-l5-s1-lumbar

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3.7K Views.  Okayama Rosai Hospital. Presented here is a novel technique of C-arm free transtubular posterolateral decompression for lumbar foraminal stenosis and lateral disc herniation under O-arm navigation.

Video: Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation

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 ...

Medicine

Full-Endoscopic Transforaminal Approach for Lumbar Discectomy

With technical advancements, the full-endoscopic transforaminal approach for lumbar discectomy (ETALD) is gaining popularity. This technique utilizes various tools and instruments, including a dilator, a beveled working sleeve, and an endoscope with a 20-degree angle and 177 mm length, equipped with a 9.3-diameter oval shaft and a 5.6 mm diameter working channel. Additionally, the procedure involves using a Kerrison punch (5.5 mm), rongeur (3-4 mm), punch (5.4 mm), tip control radioablator applying a radiofrequency current of 4 MHz, fluid control irrigation and suction pump device, 5.5 mm oval burr with lateral protection, burr round, and the diamond round. During the surgery, it is essential to identify significant landmarks, including the caudal pedicle, ascending facet, annulus fibrosis, posterior longitudinal ligament, and the exiting nerve root. The steps of the technique are relatively easy to follow, especially when utilizing the appropriate instruments and having a good understanding of the anatomy. Research studies have demonstrated comparable outcomes to open microdiscectomy techniques. ETALD presents itself as a safe option for lumbar discectomy, as it minimizes tissue disruption, results in low postoperative surgical site pain, and allows for early mobilization.

The present protocol describes the full-endoscopic transforaminal approach for lumbar discectomy, which is a safe technique that does not require muscle retraction or bone removal.

With technical advancements, the full-endoscopic transforaminal approach for lumbar discectomy (ETALD) is gaining popularity. This technique utilizes ...

Full-Endoscopic Interlaminar Approach for Decompression of Lateral Recess Stenosis

For lateral recess stenosis, extensive decompression with laminectomy is still performed in most centers. However, tissue-sparing surgeries are becoming more common. Full-endoscopic spinal surgeries have the advantages of being less invasive and offering a shorter recovery time. Here, we describe the technique of the full-endoscopic interlaminar approach for the decompression of lateral recess stenosis. The full-endoscopic interlaminar approach for the lateral recess stenosis procedure took approximately 51 min (range of 39-66 min). Blood loss could not be measured due to continuous irrigation. However, no drainage was required. There were no dura mater injuries reported in our institution. Furthermore, there were no injuries to the nerves, no cauda equine syndrome, and no hematoma formation. The patients were mobilized on the same day as surgery and discharged the next day. Therefore, the full-endoscopic technique for lateral recess stenosis decompression is a feasible procedure that lowers the operational time, complications, traumatization, and rehabilitation duration.

Technical advances and increased experience in full-endoscopic spinal surgeries enable these procedures to be performed with minimal incision, muscle retraction, and bone removal.

For lateral recess stenosis, extensive decompression with laminectomy is still performed in most centers. However, tissue-sparing surgeries are becoming ...

Full Endoscopic Interlaminar Approach for Paracentral L5-S1 Disc Herniation

The full endoscopic interlaminar approach (FEILA) is a minimally invasive technique for lumbar discectomy. It has multiple advantages over other conventional discectomy methods, including less traumatization of the soft tissues, fewer complication rates (dural injury, bleeding), rapid rehabilitation, quick return to daily life activities, and preferable cosmetic results. FEILA is a surgery with a relatively steep learning adaptation. Endoscopic surgery is a closed tubular approach, and all surgical maneuvers are performed within a uniportal single working channel. Also, the technique has not yet been standardized and well-documented. Therefore, the early learning stages of this technique may not be easy for most surgeons. Despite these, FEILA is easy, and the operation length is comparable to and even shorter than other techniques of lumbar discectomy. FEILA for lumbar discectomy could be considered a safe and effective alternative procedure for paracentral L5-S1 disc herniation. Here, we describe the technique of FEILA, including every cutoff step required to reach technical proficiency for surgeons who want to start applying this approach.

Here, we present a protocol to describe the full endoscopic interlaminar approach (FEILA) technique, including every cutoff step required to reach technical proficiency. FEILA is a surgery with a relatively steep learning adaptation. Despite this, any surgeon capable of microdiscectomy can perform FEILA with enough practice and suitable patient selection.

The full endoscopic interlaminar approach (FEILA) is a minimally invasive technique for lumbar discectomy. It has multiple advantages over other ...

Full-Endoscopic Isolation Zone Technique for the Treatment of Lumbar Disc Herniation

Lumbar disc herniation (LDH) is a type of serious sinus or sciatic nerve dysfunction caused by nucleus pulposus protrusion and annulus fibrosus tears. Its clinical symptoms often include severe low back pain, limited lumbar movement, sciatic nerve pain in the lower limbs, and even cauda equina syndrome. The common treatment for LDH is a conservative treatment scheme involving medicine, rest, and physical therapy. However, if the conservative treatment scheme is ineffective, a surgical treatment approach is adopted. Traditional open lumbar surgery has some disadvantages, including the potential for severe surgical trauma, severe blood loss during the operation, instability of the lumbar spine, and loss of the lumbar motor unit. Among the minimally invasive surgical schemes, full-endoscopic spine surgery (FESS) is undoubtedly the most appropriate and has the advantages of minimal trauma, high safety, quick postoperative recovery, and the retention of the stable structure and the motor unit of the lumbar spine. However, simultaneously, incomplete removal of the nucleus pulposus and residual nerve dysfunction after surgery can occur. To avoid these shortcomings, we studied a specific spinal endoscopy technique, the "isolation zone" surgical strategy, which can effectively block the pain from the nerve conduction pathway by completely relieving the nerve compression and nerve dysfunction through the orderly treatment of the protruding nucleus pulposus, the fissure of the annulus fibrosus, the sinus nerve, and the surrounding inflammatory soft tissues.

Here, we present a protocol for the &#34;isolation zone&#34; technique in the treatment of lumbar disc herniation (LDH) under full-endoscopic spine surgery (FESS), including intervertebral foramen formation, targeted catheterization, nucleus pulposus resection, and annulus fibrosus formation, which together completely block the pain from the nerve conduction pathway.

Lumbar disc herniation (LDH) is a type of serious sinus or sciatic nerve dysfunction caused by nucleus pulposus protrusion and annulus fibrosus tears. Its ...

A 3-Channel Endoscopic Technique for Lumbar Stenosis and Contralateral Herniation

The Third Channel-Assisted Unilateral Biportal Endoscopic Technique for Lumbar Spinal Stenosis Combined with Contralateral Disc Herniation

Unilateral biportal endoscopic (UBE) spine surgery is an emerging minimally invasive surgical (MIS) technique that has gained popularity for treating lumbar spinal stenosis, particularly in Eastern Asia. The traditional UBE technique, with two portals on one side, can achieve successful unilateral laminotomy for bilateral decompression (ULBD) and, therefore, demonstrates favorable clinical outcomes. However, in the case of lumbar spinal stenosis combined with contralateral disc herniation, it is very difficult to remove the contralateral disc herniation, especially the loose disc fragment within the deep disc. Here, a third channel of the traditional UBE technique was developed to do the discectomy within the ipsilateral endoscopic vision, with which the instruments can go vertically into the contralateral disc, allowing easy discectomy. This technique can not only achieve adequate decompression of the bilateral spinal canal but also effectively remove contralateral herniated disc fragments. This technique avoids performing another UBE procedure on the opposite side, which can potentially shorten the duration of the operation, minimize blood loss and tissue damage, and ensure sufficient neural decompression. This paper will introduce the indications and surgical operation procedures, as well as present a classical case report and follow-up data, to facilitate the application of the third channel-assisted UBE (T-UBE) technique for spine surgeons.

Author Spotlight: Unveiling the Potential of TUBE Technique in Spinal Surgery

Here, we present the third channel-assisted UBE technique, which allows for the vertical removal of herniated disc fragments. This technique can effectively address the limitations of traditional UBE techniques. This article will systematically elaborate on this procedure.

Unilateral biportal endoscopic (UBE) spine surgery is an emerging minimally invasive surgical (MIS) technique that has gained popularity for treating ...

Unilateral Biportal Endoscopy for the Treatment of Lumbar Disc Herniation

Unilateral biportal endoscopy (UBE) is a minimally invasive spinal surgery technique increasingly employed in treating degenerative lumbar diseases, such as lumbar disc herniation, lumbar spinal stenosis, and spondylolisthesis. In UBE, two independent yet interconnected surgical channels are established-one for the endoscope and the other for surgical instruments-providing a broad and clear surgical field of view. UBE offers several advantages over traditional open surgery, including reduced tissue damage, shorter hospital stays, and faster recovery times. Additionally, it combines the benefits of microscopic surgery and interlaminar endoscopy, enhancing flexibility, accuracy, and reliability during the procedure. The learning curve for UBE is shorter than that for transforaminal endoscopy, as the surgical processes closely resemble those of conventional open surgery. Despite its favorable clinical outcomes, such as reduced blood loss and shorter hospitalization, UBE carries potential complications, including epidural hematoma, dural injury, and compression of the outlet nerve root. To mitigate these risks, it is crucial to ensure appropriate patient selection, apply the correct surgical technique, and engage in careful postoperative monitoring. This article provides a detailed summary of the step-by-step surgical techniques used in UBE for treating lumbar disc herniation. It serves as a comprehensive guide to enhance practitioners' understanding of UBE. The presentation also underscores the importance of rigorous training and expertise to ensure optimal patient outcomes.

Presented here is a step-by-step surgical protocol of unilateral biportal endoscopy (UBE), a minimally invasive approach for treating lumbar disc herniation. By using two ports, surgical accuracy and flexibility are enhanced. This article provides a comprehensive description of UBE and highlights the practical application of this approach in clinical practice.

Unilateral biportal endoscopy (UBE) is a minimally invasive spinal surgery technique increasingly employed in treating degenerative lumbar diseases, such ...

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 ...

Treating Lumbar Spinal Stenosis with a Minimally Invasive Spine Surgery

Percutaneous Endoscopic Unilateral-Approach Bilateral Decompression for Lumbar Spinal Stenosis

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

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

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

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

Full-Endoscopic Foraminoplasty and Lumbar Discectomy for Single-Level Lumbar Disc Herniation

The Transforaminal Endoscopic Surgical System (TESSYS) technique has gained popularity for the treatment of lumbar disc herniations. Foraminoplasty is the key procedure in TESSYS. However, it requires advanced skills and long-term learning, which hinder its widespread adoption among surgeons. Recently, the introduction of full-endoscopic solutions has made the process more manageable. The main difference from traditional single-portal endoscopic surgery is that full-endoscopic surgery is equipped with a larger working channel, allowing full visualization of foraminoplasty and decreasing reliance on intraoperative fluoroscopy. Recently, published studies have shown that full-endoscopic foraminoplasty and lumbar discectomy (FEFLD) could achieve comparable results to conventional microdiscectomy in terms of pain relief and functional outcomes, while enhancing postoperative recovery. This study describes the technique of FEFLD in detail, including every crucial step, such as patient positioning, puncture trajectory, endoscopic dissection of the superior articular process (SAP), endoscopic foraminoplasty, and more. We hope this will be helpful to beginners who wish to apply this approach.

Compared to conventional transforaminal endoscopic surgery, full-endoscopic foraminoplasty and lumbar discectomy (FEFLD) is a unique technique that allows full visualization of foraminoplasty and reduces the need for intraoperative fluoroscopies. This article describes the surgical steps involved in the FEFLD technique, shedding light on surgical tips and potential pitfalls to ensure outstanding performance.

The Transforaminal Endoscopic Surgical System (TESSYS) technique has gained popularity for the treatment of lumbar disc herniations. Foraminoplasty is the ...