Exiting Nerve Root Research Articles

Multiple Endoscopic Access Lumbar Interbody Fusion (MALIF): A New Technique for Unilateral Biportal Endoscopic Lumbar Interbody Fusion Using Monoportal Endoscopic Spine Surgery Techniques.

This study aims to present a new endoscopic lumbar interbody fusion technique, multiple endoscopic access lumbar interbody fusion (MALIF), which applies the assisted full-endoscopic spine surgery (AFESS) technique to unilateral biportal endoscopic lumbar interbody fusion (UBE-LIF). AFESS represents an advancement over UBE by utilizing a monoportal scope in the camera portal during biportal endoscopic spine surgery, which enables greater stability, controlled irrigation for muscle preservation, and improved protection of neural structures. We performed MALIF on 15 consecutive patients with symptomatic lumbar spondylolisthesis resistant to conservative treatment and showing radiographic evidence of instability. The technique was performed through a unilateral percutaneous pedicle screw (PPS) incision, minimally exposing the lateral facet joint, followed by superior articular process (SAP) resection and interbody cage placement for indirect decompression and fusion. The mean operative time was 97.4 ± 17.5 minutes (range: 70-129 minutes), with minimal blood loss (mean: 24.3 ± 13.8 ml) and short hospital stay (mean: 15.0 ± 3.5 days). All patients showed symptomatic improvement without major complications, except for one case of transient dysesthesia that resolved within two weeks. MALIF offers three key advantages: (1) multi-angle endoscopic access to the surgical site, (2) precise endoscopic discectomy, and (3) enhanced safety through monoportal sleeve protection of the exiting nerve root. These initial results suggest that MALIF is a promising minimally invasive surgical option for lumbar interbody fusion.

An Application of Combined Transpetrosal Approach with Micro-neurovascular Transposition in Recurrent Trigeminal Neuralgia caused by Dolichoectatic Vertebral Artery

PurposeIn general, the superior cerebellar artery (SCA) is the most prevalent vessel that compresses the trigeminal nerve root exit zone (TGNREZ) and is responsible for trigeminal neuralgia (TGN). Nevertheless, the surgical outcome is less efficacious when the offending vessel is a dolichoectatic vertebrobasilar vessel (DVB). In addition, the potential for post-procedural adhesion and fibrosis renders recurrent TGN after prior surgery an extremely challenging operation. MethodsWe describe our surgical strategy and procedure that effectively resolved recurrent TGN in a patient whose offending vessel was a large DVB following standard microvascular decompression surgery. The size and nature of the offending DVB indicated that there was limited space for mobilization away from the TGNREZ, as evidenced by previous operative findings. Consequently, the patient's TGN may not be effectively treated by re-operating with the same standard lateral suboccipital approach. ResultsOur surgical approach comprised the creation of an expanded area to facilitate the mobilization of the DVB from the TGNREZ, as well as the untethering of the trigeminal nerve and its subsequent mobilization from the DVB using the transposition technique. ConclusionA combined transpetrosal approach with micro-neurovascular transposition technique was selected to achieve all objectives. A case illustration with a surgical video is demonstrated.

Anatomical assessment of the Kambin's triangle for percutaneous posterolateral transforaminal endoscopic surgery of lumbar intervertebral discs: a magnetic resonance imaging based study.

The aim of the present study was to utilize magnetic resonance imaging (MRI) as a noninvasive tool for evaluation of the Kambin's triangle safe zone. Lumbar MRIs of 67 healthy subjects were analyzed. On the coronal plane, the distance from the superior endplate to the nerve root exiting from the dura (distance a), the distance from the lateral aspect of the dura to the medial aspect of the nerve root (distance b), and the angle between the nerve root and plane of the corresponding disc (angle α) was measured. On the axial plane, the vertical distance from the upper facet surface to the exiting nerve root and root-disc distance was also measured. On the sagittal plane, foraminal height, diameter, nerve root-disc distance, and nerve root-pedicle distance were measured. On the coronal plane, right and left α angle was 50.78±4.43 (range, 48.52-51.84 degrees) and 51.07±4.08 (range, 49.25-51.91) degrees, respectively. Distance of right 'a' was 17.86±3.86 mm (range, 10.56-24.84 mm) and left 'a' was 18.03±3.73 mm (range, 10.98-24.82 mm), distance of right 'b' was 15.57±2.61 mm (range, 10.54-20.70 mm) and left 'b' was 15.46±2.68 mm (range, 10.93-19.23 mm). All these measurements increased as the spine level went down. Foraminal height and diameter decreased caudally. Nerve root-facet distance did not show change as the level went down. The study indicated that radiologic measurement is feasible to evaluate the anatomy of the Kambin's triangle. At lower lumbar levels, the exiting nerve root is at risk of injury.

Cervical Myeloradiculopathy With Bilateral Foraminal Stenosis Treated by Unilateral Biportal Endoscopic Decompression with Alternating Hemilaminectomy and Bilateral foraminotomy: A Case Report and Technical Note

Cervical myeloradiculopathy is a debilitating condition characterized by progressive spinal cord dysfunction commonly caused by degenerative changes in the cervical spine. It typically exhibits an insidious onset and progressive functional decline, along with multiple exiting nerve root entrapments bilaterally in some patients. Traditional surgical interventions, such as discectomy and fusion, are associated with some complications and limitations. Unilateral biportal endoscopic (UBE) decompression can have significant advantages over traditional techniques when cervical central and bilateral foraminal decompression is required. In this case report and technical note, we describe our experience with this novel surgical technique for the treatment of cervical myelopathy. A 67-year-old patient presented with progressive neck pain; bilateral upper extremity radiculopathy; loss of power and sensation in the C5, C6, and C7 nerve root distribution; gait imbalance, and spasticity. Magnetic resonance imaging revealed multilevel cervical spondylosis with central canal and bilateral foraminal stenosis. The patient underwent UBE central and bilateral foraminal decompression. At a 9-month follow-up visit, he was able to walk unassisted, his reflexes had returned to normal, no spasticity was observed, and he had good grip strength in both hands. This is a novel technique of UBE decompression with bilateral foraminotomy at the C4–5, C5–6, and C6–7 levels and laminectomy named “the floating tip technique.” The procedure involved bilateral 3-level lamino-foraminotomy and hemilaminotomy on both C5 and C6. A hemilamina was removed on the opposite sides, and flavectomy was performed. Postoperative computed tomography findings showed an intact, complete muscular mass with an intact central spinous process. Therefore, this method was labelled the “floating tip technique.”

Transforaminal Endoscopic Lateral Recess Decompression

Transforaminal full-endoscopic spine surgery (TF-FESS) is a minimally invasive surgical procedure that can be performed with only an 8-mm skin incision under local anesthesia. TF-FESS has been used to treat not only lumbar disc herniation, but also lumbar spinal stenosis. This paper describes transforaminal full-endoscopic lateral recess decompression. The best indication for this procedure is unilateral recess stenosis accompanied by transversing nerve root radiculopathy, with or without exiting nerve root radiculopathy. The skin entry point is about 6–8 cm from the midline, and the precise point is determined by preoperative planning. After local anesthesia, an 8-mm skin incision is made, and the cannula is placed on the surface of the superior articular process (SAP). Next, the SAP is resected from the pedicle to the tip using a high-speed drill to expose the facet joint space and flavum by the hand-down technique (gradually changing hand position to be downwards and moving the cannula inwards). After removing the flavum, the completely decompressed transversing nerve root can be clearly visualized and confirmed under fluoroscopy. Two hours postoperatively, patients can walk without restriction. Because this procedure requires the complete resection of the ventral side of the facet, it is also called full-endoscopic ventral facetectomy.

A case report on dilated engorged epidural vein causing sciatica

Sciatica is most of the time due to lumbar disc herniation. Some other pathologies such as aneurysmal bone cysts, proximal femur osteomyelitis, arachnoid cysts, facetal cysts, giant cell tumours, and pyriformis syndrome mimic sciatica are termed sciatica mimickers in literature. In this case report, we present a 66-year-old man with low back pain and left sciatica and neurogenic claudication who underwent transforaminal lumbar interbody fusion L4–5. In magnetic resonance imaging, the finding was degenerative changes with foraminal stenosis of L4–L5, but intraoperatively, we found an engorged epidural vein causing the compression of L4 exiting nerve root. The engorged epidural vein sometimes can cause sciatica which mimics the disc herniation.

How to Set Working Cannula in Endoscopic-Assisted Transforaminal Lumbar Interbody Fusion: A Morphometric Analysis Based on Computed Tomography.

There is a high risk of nerve root injury during endoscopic-assisted transforaminal lumbar interbody fusion (Endo-TLIF). This study used computed tomography (CT) imaging to assess the relationship between the exiting nerve root and its surroundings, and the corresponding intervertebral disc. We also measured the approximate position and angle for the placement of the working cannula to reduce the risk of nerve root injury during Endo-TLIF procedures in the Chinese population. This retrospective study was conducted at our institution between December 2021 and December 2022. A total of 115 patients suffering from low back pain were recruited for the study. For each participant, three-dimensional (3D) vertebral models of the lumbar segments from L3 to S1 were constructed based on their CT images. The nerve root-disc distance, cannula insertion bypass distance and angle, foraminal height and width, exiting nerve root height, and nerve root-pedicle distance were measured. A paired t-test was used to compare measurements between the left and right sides, while inter- and intraobserver reproducibility was assessed using the intraclass correlation coefficient (ICC). From L3/4 to L5/S1 segments, the ideal cannula insertion distance range was 37.51 ± 4.91-120.38 ± 37.71 mm at L3/4; 42.38 ± 5.29-116.25 ± 27.22 mm at L4/5; and 37.78 ± 4.86-69.26 ± 12.64 mm at L5/S1. The appropriate cannula insertion angle range was 30.86° ± 5.05°-62.59° ± 6.66° at L3/4; 34.30° ± 4.73°-60.88° ± 7.34° at L4/5; and 35.89° ± 4.18°-47.65° ± 7.38° at L5/S1. The height of the intervertebral foramen (IVF) gradually decreased, and the width steadily increased. The exiting nerve root height and the nerve root-pedicle distance slightly decreased caudally. From L3/4 to L5/S1, the range of working cannula insertion distance and angle gradually decreased, and the exiting nerve root height occupying the IVF gradually increased. Our measurement can reduce the risk of nerve root injury caused by inserting the working cannula during Endo-TLIF.

How to Prevent Nerve Root Injury in Uniportal Full Endoscopic Lumbar Fusion Surgery? Insights From a Cadaveric Anatomic Study With Simulation Surgery.

The study included 2 fresh-frozen cadavers. To elucidate the positional relationship between surgical instruments and nerve roots during full endoscopic facet-sparing (FE fs-TLIF) and full endoscopic facet-resecting (FE fr-TLIF) transforaminal lumbar interbody fusion and propose safe instrumentation insertion procedures and recommend cage glider designs aimed at protecting nerve roots. Endoscopic surgical techniques are increasingly used for minimally invasive lumbar fusion surgery, with FE fr-TLIF and FE fs-TLIF being common approaches. However, the risk of nerve root injury remains a significant concern during these procedures. Eight experienced endoscopic spine surgeons performed uniportal FE fr-TLIF and FE fs-TLIF on cadaveric lumbar spines, totaling 16 surgeries. Postoperation, soft tissues were removed to assess the positional relationship between the cage entry point and nerve roots. Distances between the cage entry point, traversing nerve root, and exiting nerve root were measured. Safe instrumentation design and insertion procedures were determined. In FE fr-TLIF, the mean distance between the cage entry point and traversing nerve root was significantly shorter compared with FE fs-TLIF (3.30 ± 1.35 vs . 8.58 ± 2.47mm, respectively; P < 0.0001). Conversely, the mean distance between the cage entry point and the exiting nerve root was significantly shorter in FE fs-TLIF compared with FE fr-TLIF (3.73 ± 1.97 vs . 6.90 ± 1.36mm, respectively; P < 0.0001). For FE fr-TLIF, prioritizing the protection of the traversing root using a 2-bevel tip cage glider was crucial. In contrast, for FE fs-TLIF, a single-bevel tip cage glider placed in the caudal location was recommended. This study elucidates the anatomic relationship between cage entry points and nerve roots in uniportal endoscopic lumbar fusion surgery. Protection strategies should prioritize the traversing root in FE fr-TLIF and the exiting root in FE fs-TLIF, with corresponding variations in surgical techniques. Level V.

Percutaneous lumbar interbody fusion results in less perioperative opioid usage compared to minimally invasive transforaminal lumbar interbody fusion: a single institution, multi-surgeon retrospective study.

Ultra-minimally invasive percutaneous lumbar interbody fusion (percLIF) has been demonstrated to further minimize tissue trauma and has been associated with improved clinical outcomes including decreased blood loss, post-operative pain and length of stay when compared to minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery. A single-institution retrospective study was conducted to investigate whether 1-level percLIF is associated with decreased narcotic consumption compared to 1-level MIS-TLIF in the first 24-hour following surgery. A retrospective study of patients undergoing either single-level percLIF or MIS-TLIF from January 2018 to December 2021. Opioid consumption in the 24-hour following surgery was converted into total morphine milligram equivalents (MME). The primary outcome used univariate and multivariate regression analysis to compare MME consumption between the MIS-TLIF and percLIF groups. Secondary outcome variables included, estimated blood loss, total intraoperative MME, MME at discharge, MME at 30 days post-op, exiting nerve root injury, post-anesthesia care unit (PACU) visual analogue scale (VAS) score at handoff, time to first ambulation, distance ambulated post-operative day one and hospital length of stay. A total of 51 patients (21 percLIF vs. 30 MIS-TLIF) were included in the study. Univariate regression analysis revealed that on average patients who underwent percLIF had a 24-hour postoperative MME -50.8 mg (95% CI: -91.6, -10) lower than those who had MIS-TLIF (P=0.02). On multivariable analysis, after adjusting for sex and age, 24-hour postoperative MME closely failed to meet statistical significance (P=0.06) with an average of -40.8 mg (95% CI: -83.2, 1.6) MME in percLIF patients compared to MIS-TLIF. There was no statistically significant difference in MME between MIS-TLIF and percLIF at the time of discharge and at 30 days post-op. In the setting of the current opioid epidemic in the United States and increased numbers of patients undergoing lumbar interbody fusion, spine surgeons must continue to do their part helping reduce the need for opioid prescriptions for postoperative pain management. New "ultra-MIS" techniques such as percLIF allow surgeons to further decrease tissue trauma, which should lead to reduced need for post-operative narcotic requirements.

1068 Incidence and Recovery of C5 Nerve Palsy After Various Types of Cervical Spinal Surgery: A Systematic Review and Meta-Analysis of Over 14,834 Patients

INTRODUCTION: C5 nerve palsy is a debilitating operative complication of cervical surgery and occurs commonly as many surgical approaches operate near the exiting nerve root. No prior study has attempted to identify the recovery rate of C5 nerve palsy after cervical operations, and identify the rate of which this complication becomes permanent. METHODS: A literature search of the PubMed and Embase databases was completed to identify all papers focused on cervical surgery. Studies were excluded if they did not provide the rate of C5 palsy occurrence or if they did not define what type of cervical surgery was completed. A pooled, weighted prevalence rate of C5 palsy was calculated for each type of surgery, including the rate of these becoming permanent. RESULTS: A total of 118 studies were identified and met all inclusion criteria. Of these studies, 52 were focused on laminoplasties, 24 on anterior cervical discectomy fusions (ACDF), 22 on laminectomies without fusion, and 20 on posterior cervical fusions (PCF). Laminectomies had the highest incidence of C5 palsy at a pooled rate of 7.08% (95% Confidence Interval [CI], 4.74%-10.46%, I2 = 87%, P &lt; .01), of which 0.05% (CI = 0.00%-0.90%) were permanent. This was followed by PCFs with a rate of 6.70% (CI = 4.50%-9.85%), with the effects being permanent at a rate of 0.04% (CI = 0.00%-1.20%). Laminoplasties had a C5 palsy incidence of 5.49% (CI = 4.65%-6.47%), of these 0.02% (CI = 0.00%-0.11%) were permanent. ACDFs had the lowest incidence at a rate of 4.50% (CI = 2.56%-7.79%), of which only 0.02% (CI = 0.04%-0.08%) were permanent. CONCLUSIONS: C5 nerve palsy is a relatively common complication after all types of cervical surgeries with increased rates in posterior approaches, however the rate of these becoming permanent is minimal.

Acute Pain Management in Vatakaphaja Gridhrasi

Gridhrasi is one of the Vataja Nanatmaja Vyadhi in which the vitiated Vata afflicts the Kandara and Sira of lower limb leading to Stambha, Ruk, Toda along with Spandana starting from Kati Pradesha to Prustha, Janu, Jangha and Pada of either one side or both side of the lower limbs. Due to similarities in the clinical presentation, it can be studied under the spectrum of Intervertebral Disc Prolapse of lumbar spine. It is a condition affecting the spine in which the annulus fibrosus is damaged enabling nucleus pulposus to herniate, due to which there will be compression of Spinal Cord or the exiting nerve roots causing severe pain in the low back radiating to lower limbs. The incidence of Herniated disc is about 5 to 20 cases per 1000 adults annually and is most common in male patients when compared with female. In this case a male patient of age 36 suffering with acute pain in the low back region was effectively managed by Nadi Sweda followed by dry cupping for 7 days, followed by Patra Pinda Sweda for 7 days. The study shows significant relief in the pain and remarkable improvement in the range of movement of lumbar spine.

Transforaminal Contrast Injection Before Computed Tomography-Guided Lateral Endoscopic Lumbar Diskectomy Improves Visualization of Exiting Nerve Root.

Percutaneous endoscopic lumbar diskectomy (PELD) is an effective, minimally invasive method for removal of lateral lumbar disk herniations. This minimally invasive technique can be applied with high success and lead to faster recovery than traditional methods. Unfortunately, adoption of these techniques in the United States has been slow. A significant barrier to using this technique is often an inability to completely visualize relevant anatomy and increased operative times. In this article, we describe a technique using computed tomography (CT) guidance in conjunction with a neurogram to perform a PELD. We detail the steps in the technique and its advantages to the surgeon performing it. After a patient is placed supine on a table, a transforaminal injection of contrast is performed under fluoroscopic guidance. Then, after sterilizing and draping in a normal fashion, an intraoperative CT scan is taken with a reference frame in place. During the procedure, this allows for the CT guidance to have the exiting nerve root clearly outlined. This procedure was successfully performed in a single patient, allowing greater visualization of the exiting nerve root during a difficult revision PELD case. No complications were experienced. A novel technique using a neurogram with CT guidance during a PELD was used to assist with identification of anatomy and decompression of the exiting nerve root. This technique was used without complications.

Dorsal Root Ganglion Pulsed Neuromodulation Radiofrequency Treatment has Significant Clinical Efficacy in Chronic Spinal-origin Pain, Bringing Noticeable Improvement in Symptoms and Sleep Quality for Patients

Background Chronic spinal-origin pain poses a substantial clinical challenge, prompting the investigation of novel treatment modalities. This study aims to evaluate the potential application of spinal nerve dorsal root ganglion radiofrequency treatment in addressing chronic spinal-origin pain. Methods The study encompassed patients undergoing treatment for chronic spinal-origin pain, with a particular focus on those experiencing pain localized in specific regions. Inclusion criteria comprised patients with conditions such as a herniated intervertebral disc or foraminal stenosis leading to compression of descending or exiting nerve roots, accompanied by reported radicular pain in the lower limb. Results There was no significant difference in comparability between the two groups (P > 0.05). The clinical effective rate in the study group was significantly higher than that in the control group (P < 0.05). The VAS scores of the study group at 2 weeks and one month after treatment were significantly lower than those of the control group (P < 0.05). The PSQI index of the study group after treatment was significantly lower than that of the control group (P < 0.05). There was no significant difference in the incidence of complications between the two groups (P > 0.05). Conclusion Spinal nerve dorsal root ganglion radiofrequency treatment has significant clinical efficacy in chronic spinal-origin pain, bringing noticeable improvement in symptoms and sleep quality for patients. The occurrence of complications is relatively low, and it can be reduced through strict operational standards and pre- and post-operative management. However, caution should be exercised in its widespread application, but it is worthy of broad clinical use.

A Comparison of Precision and Safety using Three Recognized Ultrasound-Guided Approaches to Cervical Medial Branch Blocks: A Cadaver Study

BACKGROUND: Ultrasound (US) guidance is widely used for needle positioning for cervical medial branch blocks (CMBB) and radiofrequency ablation, however, limited research is available comparing different approaches. OBJECTIVE: We aimed to assess the accuracy and safety of 3 different US-guided approaches for CMBB. STUDY DESIGN: A cadaveric study divided into ultrasound-guided needle placement and fluoroscopy evaluation stages. SETTING: Department of Pathology, Forensic, and Insurance Medicine, Semmelweis University. METHODS: Sonographically guided third occipital nerve (TON), C3, C4, C5 and C6 medial branch injections and radiology evaluations were performed. The 3 approaches compared were: 1. ES (published by Eichenberger-Siegenthaler): US probe in the coronal plane to visualize the cervical articular pillars, needle approach out of the plane, from anterior to posterior. 2. Fi (published by Finlayson): US probe in the transverse plane to visualize a cervical articular pillar and its lamina, needle approach in the plane, from posterior to anterior. 3. FiM (Modified Finlayson approach): Needles are placed as in Fi, but then adjusted with a coronal view of the cervical articular pillars. Fluoroscopy images were taken and later evaluated, for “crude”, “high precision” and “dangerous” placement. RESULTS: One hundred and fifty-five needle placements were assessed (10 were excluded, as no anterior-posterior fluoroscopy images were saved). Interobserver agreement on position of needle placement between the 5 observers was very high; the Fleiss’ Kappa was 0.921. For crude placement, no significant differences were identified between various approaches; (77.6%, 79.5%, and 75.6% for the ES, Fi, and FiM respectively). However, for placement in predefined high-precision zones, ES resulted in significantly more success (ES: 42.9%, Fi: 22.7%, and FiM: 24.4%, P = 0.032). Fi and FiM resulted in no dangerous placements, while ES led to the potential compromise of the exiting nerve root and vertebral artery on three occasions. In 10% of the placements, the levels were identified wrongly, with no difference between the various approaches. LIMITATIONS: Feedback from a live patient, may prevent some existing nerve root injections, unlike in a cadaver. Though a higher number of needles were placed in this study than in most available publications, the number is still low at each individual medial branch level. CONCLUSION: Fi proved safer than ES. Fi was equally successful in targeting the articular pillar, however, ES proved the most successful in placing the needle in the center of the articular pillar. Adding another, (coronal) US view to check needle position in FiM did not improve safety or precision. Identifying CMB levels with the US is challenging with all approaches, therefore we still recommend using fluoroscopy for level identification. While there were pros and cons with either procedure, the efficacy findings of previous papers were not replicated on elderly cadavers with arthritic necks. KEY WORDS: Cervical facet, medial branch block, safety, accuracy, ultrasound, fluoroscopy

Symptomatic Long-segment Extradural Arachnoid Cyst: An Interesting Case Report with Literature Review

Abstract Extradural spinal arachnoid cysts are rare lesions which when become symptomatic lead to progressive neurological signs and symptoms. The spectrum of presentation is myriad and surgical intervention is reserved for symptomatic patients. A 17-year-old boy presented with features of progressive spastic paraparesis for the last 5 months. Initial radiological work-up was suggestive of thoracolumbar extradural cystic lesion. Computed tomography myelography was not able to detect the dural defect. He underwent surgical excision of the cyst under intraoperative neuromonitoring. The lesion was excised in single piece and the intradural communication was noticed along an exiting nerve root. The dural defect at the mid-length of the lesion was identified and closed watertight. Significant improvement in the sensory-motor complaints was noted in the postoperative period. The identification of the dural defect and ensuring its closure along with the complete removal of the cyst is the key to avoid recurrence and is the standard procedure of choice.

Transforaminal full-endoscopic decompression under local anesthesia for foraminal stenosis due to stable L5 isthmic spondylolisthesis, a technical note and review:Pars crisscross decompression.

Foraminal stenosis is one of the types of lumbar spinal stenosis. The pathology can be treated minimally invasively by full-endoscopic spine surgery (FESS). The final challenge in transforaminal FESS is foraminal stenosis in patients with stable isthmic spondylolisthesis at L5. This article provides a step-by-step explanation of how to achieve complete decompression. A cannula of 8 mm in diameter is docked at the base of the superior articular process of the sacrum. The pars crisscross that consists of the superior articular process at S1, the floating lamina, the inferior articular process at L4, and the pars ragged edge is then clearly seen endoscopically. Visualization of the pars crisscross is key to successful decompression. Starting with the superior articular process at S1, followed by partial removal of the floating lamina. Next, the tip of the inferior articular process at L4 is removed. The pars ragged edge is then carefully shaved. Finally, decompression of the exiting nerve root at L5 is confirmed. This report provides the first step-by step description of full-endoscopic decompression of foraminal stenosis under local anesthesia in patients with stable L5 isthmic spondylolisthesis, which we have named "full-endoscopic pars crisscross decompression". J. Med. Invest. 71 : 191-196, August, 2024.

Lumbar Dorsal Root Ganglion Pulsed Radiofrequency for Spinal Stenosis with an Atypical Fluoroscopic Neurogram: A Case Study

Background: We present a case of an atypical fluoroscopic neurogram pattern for complex chronic axial low back pain during a lumbar dorsal root ganglia (DRG) pulsed radiofrequency stimulation. Case Report: A 70 year old female with a history of complex chronic axial low back pain with radicular leg pain. Initially her pain was described as intermittent, burning, and sharp with an intensity of 9/10 on the Numeric Rating Scale (NRS). This pain worsens with ambulation, lumbar extension, turning, weight bearing and spinal loading activities. MRI imaging noted lumbar anterolisthesis, moderate to severe central spinal stenosis, and mild bilateral neural foraminal space narrowing. From these findings, her pain is likely secondary to components of sacroiliac (SI) joint dysfunction, lumbar facetogenic pain, lumbar radiculitis, and spinal stenosis with neurogenic claudication. A multimodal and multidisciplinary rehabilitation approach involving minimally invasive interventional procedures and medication management was implemented with varying pain relief. She responded to L5 transforaminal epidural nerve root injections, SI joint prolotherapy, and sacral lateral branch radiofrequency ablation. She completed bilateral L5 DRG pulsed radiofrequency stimulation, which did not provide radicular pain relief. We performed a unilateral L4 DRG pulsed radiofrequency stimulation, which revealed an atypical L4 fluoroscopic neurogram pattern. At the 3 month follow up she reported the pain severity to have a NRS between 7-8/10. At 4 months, the pain severity was reported to have a NRS between 4-6/10 with subjective improvements with her daily activities. Conclusion: In a normal transforaminal epidural fluoroscopic neurogram, the anteroposterior view should demonstrate contrast spread medially around the pedicle and laterally following the exiting nerve root. In the case of this patient the combined anatomical presentation of anterolisthesis, central spinal canal stenosis, and circumferential disc bulging are all potential reasons for insufficient contrast passage resulting in the atypical neurogram.

Using Novel Segmentation Technology to Define Safe Corridors for Minimally Invasive Posterior Lumbar Interbody Fusion.

There has been a rise in minimally invasive methods to access the intervertebral disk space posteriorly given their decreased tissue destruction, lower blood loss, and earlier return to work. Two such options include the percutaneous lumbar interbody fusion through the Kambin triangle and the endoscopic transfacet approach. However, without accurate preoperative visualization, these approaches carry risks of damaging surrounding structures, especially the nerve roots. Using novel segmentation technology, our goal was to analyze the anatomic borders and relative sizes of the safe triangle, trans-Kambin, and the transfacet corridors to assist surgeons in planning a safe approach and determining cannula diameters. The areas of the safe triangle, Kambin, and transfacet corridors were measured using commercially available software (BrainLab, Munich, Germany). For each approach, the exiting nerve root, traversing nerve roots, theca, disk, and vertebrae were manually segmented on 3-dimensional T2-SPACE magnetic resonance imaging using a region-growing algorithm. The triangles' borders were delineated ensuring no overlap between the area and the nerves. A total of 11 patients (65.4 ± 12.5 years, 33.3% female) were retrospectively reviewed. The Kambin, safe, and transfacet corridors were measured bilaterally at the operative level. The mean area (124.1 ± 19.7 mm2 vs 83.0 ± 11.7 mm2 vs 49.5 ± 11.4 mm2) and maximum permissible cannula diameter (9.9 ± 0.7 mm vs 6.8 ± 0.5 mm vs 6.05 ± 0.7 mm) for the transfacet triangles were significantly larger than Kambin and the traditional safe triangles, respectively (P < .001). We identified, in 3-dimensional, the borders for the transfacet corridor: the traversing nerve root extending inferiorly until the caudal pedicle, the theca medially, and the exiting nerve root superiorly. These results illustrate the utility of preoperatively segmenting anatomic landmarks, specifically the nerve roots, to help guide decision-making when selecting the optimal operative approach.

Neuroforaminal Stenosis in the Lumbosacral Spine: A Scoping Review of Pathophysiology, Clinical Manifestations, Diagnostic Imaging, and Treatment

OBJECTIVE To conduct the first scoping review of lumbosacral neuroforaminal stenosis with respect to the pathophysiology, symptomatic manifestations, diagnostic imaging, and treatment options. METHODS A scoping literature review was conducted in accordance with the recommendations set forth by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), with English language restrictions stipulated to include articles pertaining to lumbosacral neuroforaminal stenosis. Databases maintained by PubMed, National Library of Medicine, Cochrane Central Register of Controlled Trials (Ovid), Scopus (Elsevier), Web of Science (Thomson Reuters), and Google Scholar were queried from their inception date through December 2022. SUMMARY OF THE EVIDENCE A total of 276 articles were reviewed and 29 articles were included within the study. Within these articles, the anatomic origins of neuroforaminal stenosis were reviewed in detail and the resulting clinical manifestations were discussed. Recent studies evaluating the efficacy of existing diagnostic imaging modalities were summarized, along with potential future methods to improve sensitivity for detecting this entity and measuring foraminal stenosis via novel imaging techniques. Based on the literature, the conservative management and surgical treatment of lumbosacral foraminal stenosis were discussed. CONCLUSIONS Lumbar neuroforaminal stenosis represents a significant source of radicular pain that is often compounded by delayed diagnosis and incomplete treatment. This article represents the first scoping review of lumbosacral neuroforaminal stenosis with focus on diagnosis, management, and treatment for associated radicular pain. The goal is to reduce the incidence of untreated or unrecognized neuroforaminal stenosis in the setting of a complex decompression and fusion, as well as to promote minimally invasive surgery to address radicular pain from neuroforaminal stenosis. Recent advances in diagnostic imaging and surgical techniques have the potential to improve the timeliness and durability of patients’ treatment options. Future directions for the diagnostic imaging of foraminal stenosis include efforts aimed at developing the nascent field of computerized mapping to reliably quantify stenosis and its impact on the exiting nerve root and associated dorsal root ganglia.

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.