Full endoscopic laminotomy decompression versus anterior cervical discectomy and fusion for the treatment of single-segment cervical spinal stenosis: a retrospective, propensity score-matched study

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) is the standard procedure for the treatment of cervical spinal stenosis (CSS), but complications such as adjacent segment degeneration can seriously affect the long-term efficacy. Currently, posterior endoscopic surgery has been increasingly used in the clinical treatment of CSS. The aim of this study was to compare the clinical outcomes of single-segment CSS patients who underwent full endoscopic laminotomy decompression or ACDF.

METHODS

138 CSS patients who met the inclusion criteria from June 2018 to August 2020 were retrospectively analyzed and divided into endoscopic and ACDF groups. The propensity score matching (PSM) method was used to adjust the imbalanced confounding variables between the groups. Then, perioperative data were recorded and clinical outcomes were compared, including functional scores and imaging data. Functional scores included Visual Analog Scale of Arms (A-VAS) and Neck pain (N-VAS), Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), and imaging data included Disc Height Index (DHI), Cervical range of motion (ROM), and Ratio of grey scale (RVG).

RESULTS

After PSM, 84 patients were included in the study and followed for 24-30 months. The endoscopic group was significantly superior to the ACDF group in terms of operative time, intraoperative blood loss, incision length, and hospital stay (P < 0.001). Postoperative N-VAS, A-VAS, JOA, and NDI were significantly improved in both groups compared with the preoperative period (P < 0.001), and the endoscopic group showed better improvement at 7 days postoperatively (P < 0.05). The ROM changes of adjacent segments were significantly larger in the ACDF group at 12 months postoperatively and at the last follow-up (P < 0.05). The RVG of adjacent segments showed a decreasing trend, and the decrease was more marked in the ACDF group at last follow-up (P < 0.05). According to the modified MacNab criteria, the excellent and good rates in the endoscopic group and ACDF group were 90.48% and 88.10%, respectively, with no statistically significant difference (P > 0.05).

CONCLUSION

Full endoscopic laminotomy decompression is demonstrated to be an efficacious alternative technique to traditional ACDF for the treatment of single-segment CSS, with the advantages of less trauma, faster recovery, and less impact on cervical spine kinematics and adjacent segmental degeneration.

Comparison of efficacy between endoscope-assisted anterior cervical discectomy and fusion (ACDF) and open ACDF in the treatment of single-segment cervical spondylotic myelopathy

BACKGROUND

In this study, we compared the clinical efficacy of endoscope-assisted anterior cervical discectomy and fusion (ACDF) with open ACDF in the treatment of single-segment cervical spondylotic myelopathy.

METHODS

A retrospective analysis was performed on 52 patients with single-segment cervical spondylotic myelopathy between June 2021 and February 2022, including 33 males and 19 females, with a mean age of 58.42 ± 9.26) years. Among them, 28 patients were treated with endoscope-assisted ACDF (Group A), including 2 cases of C4/5 segment, 16 cases of C5/6 segment, and 10 cases of C6/7 segment; 24 patients were treated with open ACDF (Group B), including 4 cases of C4/5 segment, 11 cases of C5/6 segment, and 9 cases of C6/7 segment. The operation time, intraoperative blood loss, hospital stay, and complications were recorded and compared between the two groups. The Visual Analogue Scale (VAS) and the Japanese Orthopaedic Association (JOA) score were used for clinical evaluation during the follow-up in the 1st month and 3rd month after surgery, and at the final follow-up.

RESULTS

The 52 patients were followed up on average for 13.04 months (12-17 months). The operation time in Group A and Group B was (105.18 + 8.66) minutes and (81.88 + 6.05) minutes, the intraoperative blood loss was (84.29 + 13.45) mL and (112.92 + 17.81) mL, and the hospital stay was (6.75 + 1.29) days and (7.63 + 1.41) days, respectively. The difference between the two groups was statistically significant (P < 0.05). The VAS and JOA scores in the 1st month and the 3rd month after surgery and the last follow-up significantly improved in both groups compared with those before surgery (P < 0.05). The VAS and JOA scores of Group A in the 1st month, 3rd month after surgery, and the last follow-up were better than those in Group B (P < 0.05). The complication rate in Group A was 7% (2/28), which was not significantly different from the 17% (4/24) in Group B (P > 0.05).

CONCLUSION

Both endoscope-assisted ACDF and open ACDF can achieve satisfactory clinical efficacy in the treatment of single-segment cervical spondylotic myelopathy. Although the operation time of endoscope-assisted ACDF is prolonged, it has the advantages of clear vision, thorough decompression, less blood loss, and reduced risk of nerve damage, and is worthy of clinical promotion and application.

Comparison of percutaneous endoscopic interlaminar discectomy and conventional open lumbar discectomy for L4/5 and L5/S1 double-segmental lumbar disk herniation

OBJECTIVE

Although spinal endoscopic techniques have shown great advantages in the treatment of single-segment lumbar disk herniation (LDH), the therapeutic advantages for double-segment LDH are controversial. To compare the outcomes of percutaneous endoscopic interlaminar discectomy (PEID) versus conventional open lumbar discectomy (COLD) for the treatment of L4/5 and L5/S1 double-segmental LDH.

METHODS

From January 2016 to September 2021, we included 50 patients with double-segmental LDH who underwent PEID (n = 25) or COLD (n = 25). The clinical outcomes between the two groups were evaluated using the visual analog scale (VAS), the Oswestry disability index (ODI), and the modified MacNab criteria. Moreover, the incision length, operation time, intraoperative fluoroscopy time, postoperative bedtime, hospital stays, and complications were also recorded and compared after surgery.

RESULTS

In both groups, the VAS and ODI scores at different timepoints postoperatively were significantly improved compared with those preoperatively (P < 0.05) According to the modified MacNab criteria, the excellent or good outcome rate was 92% in the PEID group and 88% in the COLD group. The PEID group had shorter incision length, postoperative bedtime, and hospital stays than the COLD group. However, the operation time was shorter and intraoperative fluoroscopy time was fewer in the COLD group. In addition, there was no significant difference between the two groups in terms of surgical complications during the postoperative follow-up period.

CONCLUSIONS

Both PEID and COLD have good efficacy and high safety for management of L4/5 and L5/S1 double-segmental LDH. Compared with the COLD group, the PEID group had more operative time as well as more intraoperative fluoroscopy, but it had a more minimally invasive surgical incision as well as faster postoperative recovery.

Uniportal Thoracic Endoscopic Unilateral Laminotomy with Bilateral Decompression of Thoracic Ossification of Ligamentum Flavum: A Systematic Review of Current Literature

BACKGROUND

Thoracic ossification of ligamentum flavum (TOLF) is a rare disease that often results in worsening neurologic sequelae if left untreated. Although the gold standard treatment for TOLF is open posterior laminectomy, it is often accompanied by high rates of complications and perioperative morbidity. There have been studies looking into feasibility of endoscopic posterior decompression for TOLF, citing potential for lower perioperative morbidity and achieving similar functional outcomes to its open laminectomy counterparts. We provide an up-to-date systematic review of clinical outcomes after endoscopic posterior decompression for TOLF from the latest assemblage of evidence.

METHODS

A systematic review of the technique was conducted from May 2000 to May 2023. Articles were selected based on PRISMA guidelines. Eligibility of studies was independently by 2 reviewers, with disagreements resolved by a third author.

RESULTS

Nineteen primary references comprising 337 patients with TOLF who underwent endoscopic posterior decompression were included in the systematic review. Mean follow-up time across all studies ranged from 8.9 to 65.3 months. Mean age ranged from 51.2 to 63 years, with mean intraoperative blood loss ranging from 15 to 62 mL. There is significant improvement in visual analog scale (VAS) score, VAS back, VAS leg, modified Japanese Orthopaedic Association score, and Oswestry Disability Index compared with preoperative recorded values across all studies, with low rates of complications reported.

CONCLUSIONS

Endoscopic posterior spinal decompression is a safe and effective technique for treatment of TOLF, with a low rate of complications and improvement in pain and function.

Preoperative dyeing technique for decreasing radiation exposure in unilateral biportal endoscopic spine surgery

BACKGROUND

Minimally invasive surgery has many advantages, including early recovery and cosmetic preservation. However, the higher radiation exposure to physicians and patients has drawbacks. Preoperative tissue dyeing techniques are feasible options for reducing radiation exposure and procedure time, but their efficacy has not yet been evaluated. Therefore, this study aimed to evaluate surgical outcomes and reduce radiation exposure during unilateral biportal endoscopy surgery.

METHODS

This was a prospective, case-controlled analysis in a tertiary hospital. Patients receiving experimental tissue dye and controls in the non-dye group were compared from May 2020 to September 2021. The interlaminar posterolateral approach (IPA) and the far lateral approach (FLA) were analyzed separately among all single-level spinal procedures without instrumentation. Operative details (operation time, improvement of back and leg pain, and length of hospital stay) and radiation exposure (dose and duration) were compared. Results; A total of 88 cases were included, consisting of 64 interlaminar approaches (experimental: 33, control: 31) and 24 far lateral approaches (experimental: 13 and control: 11). In the IPA approach, the patient and physician radiation exposure doses and duration decreased significantly. Conversely, for the FLA, only the duration of the physician exposure decreased significantly.

CONCLUSIONS

Preoperative tissue dyeing techniques using IPA can reduce radiation exposure for physicians and patients. However, a decrease in the duration of radiation was observed only in physicians using the FLA. The dyeing technique is effective in IPA, but the efficacy of FLA is doubtful.

Treatment of Refractory Multilevel Thoracic Spondylodiscitis Using Ultra-Minimally Invasive Endoscopic Approach for Debridement and Drainage: A Technical Note, Intraoperative Video, and Literature Review

OBJECTIVE/BACKGROUND

Spondylodiscitis is an infection of the spinal column which can result in pain, deformity, instability, and/or neurologic deficits. When surgical treatment is required for thoracic spondylodiscitis, invasive open approaches are often utilized due to the ventral location of the pathology.

METHODS

We describe the use of a spinal endoscope to perform drainage and debridement of infected tissue through a transforaminal/intradiscal approach in a patient with multilevel thoracic spondylodiscitis refractory to antibiotic therapy. Illustrative videos are provided, as well as a review of the relevant literature.

RESULTS

A total of 188 patients were included in the systematic review. The mean positive reported culture rate was 76% (117/154 patients). The mean preoperative visual analog scale score was 6.8 (n = 114), and the mean postoperative visual analog scale score was 1.8 at 1 week postoperatively (n = 56) and 1.01 at the final follow-up (n = 114). The most common surgical approach was transforaminal/intradiscal (103/188 patients, 54.8%). The mean reoperation rate was 9.1%. The mean complication rate was 5.25%, with complications including increased transient radicular pain, infection, hardware failure, and new unspecified neurological deficits.

CONCLUSION

This case and those highlighted in our literature review demonstrate that endoscopic treatment for thoracic spondylodiscitis is a viable alternative to traditional open surgery in many cases.

Comparison of the Clinical Efficacy of Transforaminal Endoscopy and Microtubular Technology for the Treatment of Lumbar Dumbbell-Shaped Tumors

OBJECTIVE

To analyze differences in feasibility and efficacy between the paravertebral approach and microtubular tumorectomy (PAMT) or percutaneous transforaminal endoscopic tumorectomy (PTET) for the treatment of lumbar dumbbell-shaped tumors.

METHODS

Clinical data of dumbbell-shaped lumbar tumors in patients treated with PAMT or PTET in our hospital between June 2015 and November 2020 were retrospectively analyzed. The gross total resection (GTR) rate, operation time, estimated blood loss, postoperative hospital stay (PHS), postoperative neurological function, and spinal stability were compared between the 2 surgical methods. Neurological improvement was assessed using the pain visual analogue scale (VAS) and the Japanese Orthopaedic Association (JOA) score.

RESULTS

Fifteen cases of GTR (93.8%) and 1 case of subtotal resection were included in the PTET group, whilst all 18 patients in the PAMT group achieved GTR. There was no significant difference in the GTR rate, operation time, and PHS between the PAMT and PTET groups. The estimated blood loss was significantly lower in the PTET group than in the PAMT group. At the last follow-up, there was no significant difference in the VAS or JOA scores between PTET and PAMT. No tumor recurrence or spinal instability was observed in either group during the follow-up period.

CONCLUSION

Both PAMT and PTET can achieve Eden type III-IV lumbar 1-stage tumor resection without additional spinal internal fixation due to reduced muscle, ligament, and facet joint damage. No lumbar instability and tumor recurrence occurred, and neurological function was improved.

Minimally Invasive Spine Surgery: An Overview

Spinal surgery is undergoing a major transformation toward a minimally invasive paradigm. This shift is being driven by multiple factors, including the need to address spinal problems in an older and sicker population, as well as changes in patient preferences and reimbursement patterns. Increasingly, minimally invasive surgical techniques are being used in place of traditional open approaches due to significant advancements and implementation of intraoperative imaging and navigation technologies. However, in some patients, due to specific anatomic or pathologic factors, minimally invasive techniques are not always possible. Numerous algorithms have been described, and additional efforts are underway to better optimize patient selection for minimally invasive spinal surgery (MISS) procedures in order to achieve optimal outcomes. Numerous unique MISS approaches and techniques have been described, and several have become fundamental. Investigators are evaluating combinations of MISS techniques to further enhance the surgical workflow, patient safety, and efficiency.

Foundations in Spinal Endoscopy

Spinal endoscopy has revolutionized the way spine surgeons deliver minimally invasive care for appropriately selected patients. The evolution of endoscopy has been tumultuous since its beginnings as a "blind" percutaneous procedure to access the disk until the present state, in which complex decompressions and even fusions can be accomplished through subcentimeter incisions. Engineering has played a crucial role in this evolution with advances in optics, illumination, and instrumentation that have allowed surgeons to work safely and efficiently in smaller and smaller corridors. Finally, the adaptation of enhanced recovery after surgery protocols have complemented the benefits offered by spinal endoscopy to help patients return to the quality of life they seek through surgical intervention. In this article, we explore foundational elements of spinal endoscopy and look ahead to the future of this maturing field.

Innovations in Spinal Endoscopy

Innovations in spinal endoscopy technology and technique have broadened their applications during the past 10 years. Smaller outer-diameter working-channel endoscopes have permitted safe usage in the cervical spine for full endoscopic decompressions. Endoscopic fusions have now been widely reported, leveraging compatible instrumentation for disc preparation and expandable interbody grafts. This ultra-minimally invasive technique has also enabled the performance of fusion procedures in awake patients under monitored anesthesia care, affording speedier recovery and treatment options for those unable to undergo general anesthesia. Revision surgery after open or minimally invasive posterior discectomy or instrumentation can now be performed with endoscopic techniques, which often leverage the transforaminal approach to avoid scar tissue and adhesions. These procedures, among other endoscopic surgeries, are now being increasingly performed in ambulatory surgery centers, as safe outcomes, economic benefits to the healthcare system, and patients' desire to recover at home are becoming more apparent. Finally, the standardization of endoscopic terminology, which has long been a confounder to proper communication and education in this field, has recently been addressed by leading experts in a consensus document, which will serve as the foundation for future collaborative advancements.

Improving effect of microendoscopic decompression surgery on low back pain in patients with lumbar spinal stenosis and predictive factors of postoperative residual low back pain: a single-center retrospective study

BACKGROUND

Although there are reports on the effectiveness of microendoscopic laminotomy using a spinal endoscope as decompression surgery for lumbar spinal stenosis, predicting the improvement of low back pain (LBP) still poses a challenge, and no clear index has been established. This study aimed to investigate whether microendoscopic laminotomy for lumbar spinal stenosis improves low back pain and determine the preoperative predictors of residual LBP.

METHODS

In this single-center retrospective study, we examined 202 consecutive patients who underwent microendoscopic laminotomy for lumbar spinal stenosis with a preoperative visual analog scale (VAS) score for LBP of ≥40 mm. The lumbar spine Japanese Orthopaedic Association (JOA), and VAS scores for LBP, leg pain (LP), and leg numbness (LN) were examined before and at 1 year after surgery. Patients with a 1-year postoperative LBP-VAS of ≥25 mm composed the residual LBP group. The preoperative predictive factors associated with postoperative residual LBP were analyzed.

RESULTS

JOA scores improved from 14.1 preoperatively to 20.2 postoperatively (p < 0.001), LBP-VAS improved from 66.7 to 29.7 mm (p < 0.001), LP-VAS improved from 63.8 to 31.2 mm (p < 0.001), and LN-VAS improved from 63.3 to 34.2 mm (p < 0.001). Ninety-eight patients (48.5%) had a postoperative LBP-VAS of ≥25 mm. Multiple logistic regression analysis revealed that Modic type 1 change (odds ratio [OR], 5.61; 95% confidence interval [CI], 1.68-18.68; p = 0.005), preoperative VAS for LBP ≥ 70 mm (OR, 2.19; 95% CI, 1.17-4.08; p = 0.014), and female sex (OR, 1.98; 95% CI, 1.09-3.89; p = 0.047) were preoperative predictors of residual LBP.

CONCLUSION

Microendoscopic decompression surgery had an ameliorating effect on LBP in lumbar spinal stenosis. Modic type 1 change, preoperative VAS for LBP, and female sex were predictors of postoperative residual LBP, which may be a useful index for surgical procedure selection.

Percutaneous Spinal Endoscopic Treatment of Symptomatic Sacral Tarlov Cysts

OBJECTIVE

To examine the surgical procedure for and the clinical efficacy of using spinal endoscopy for sacral Tarlov cyst treatment.

METHODS

A retrospective analysis of patients with sacral Tarlov cysts who underwent spinal endoscopy treatment from August 2018 to January 2020 at the Department of Neurosurgery, Xuanwu Hospital, China, was carried out.

RESULTS

Spinal endoscopy treatment was performed in 15 patients with sacral Tarlov cysts (6 males, 9 females). Mean patient age was 41.3 years (range, 19-67 years). Mean follow-up period was 15.6 months (range, 12-26 months). Clinical presentations of patients included sacrococcygeal and lower limb pain (n = 14), paresthesia (n = 7), lower limb motor disorder (n = 1), bowel dysfunction (n = 4), and urinary dysfunction (n = 3). Surgeries were successfully completed in all patients. Pain was significantly alleviated after surgery in 12 (85.7%) patients. Visual analog scale scores before surgery, at 1 day and 3 months after surgery, and at last follow-up were 5.9 ± 1.2, 2.9 ± 1.5, 2.3 ± 1.3, and 2.6 ± 1.0. The postoperative visual analog scale scores were significantly decreased compared with the preoperative score (all P < 0.01). Among the patients with paresthesia, 4 (57.1%) experienced improved symptoms. Muscle strength recovered from grade 4 to grade 5 after surgery in 1 patient with lower limb motor disorder. Two (50%) of 4 patients with bowel dysfunction and 2 (66.7%) of 3 patients with urinary dysfunction experienced functional improvement. Postoperative magnetic resonance imaging showed that cyst filling was satisfactory, and cyst recurrence was not observed.

CONCLUSIONS

Spinal endoscopy shows preliminary clinical efficacy for treatment of sacral Tarlov cysts and is safe and effective.

Percutaneous Spinal Endoscopic Combined with Thoracoscopic Surgery for Treatment of Thoracic Eden IV Dumbbell Tumors

OBJECTIVE

Thoracic Eden IV dumbbell tumors are rare conditions characterized by neoplasms that arise from neurogenic elements, with intraforaminal and posterior mediastinal involvement. Surgical resection is commonly performed to treat thoracic Eden IV dumbbell-shaped tumors. The combined thoracic-neurosurgical approach is a routine surgical procedure according to the literature. We present our experience with resection of thoracic Eden IV dumbbell tumors with combined percutaneous spinal endoscopic and thoracoscopic procedures in a single stage.

METHODS

A retrospective review of 7 patients undergoing spinal endoscopic combined with thoracoscopic surgery for thoracic Eden IV dumbbell tumors was performed in our department between 2017 and 2020. Patient demographics, clinical features, operative reports, and preoperative and postoperative images were reviewed.

RESULTS

Complete resection was achieved in the 7 cases. The mean operative time was 207 minutes (range, 160-310 minutes), with mean estimated blood loss of 47 mL (range, 20-80 mL). The mean chest drain duration was 3 days (range, 2-4 days), and the mean hospital stay was 7 days (range, 5-8 days). No operative complications were observed. During the follow-up period, there were no obvious complications, tumor recurrence, or spinal instability.

CONCLUSIONS

Percutaneous spinal endoscopic combined with thoracoscopic surgery for the treatment of Eden IV type thoracic dumbbell tumors is a novel, safe, and effective surgical method that can not only remove tumors inside and outside of the thoracic intervertebral foramen in a single stage but also minimize damage to the normal structure of the spine and help in early recovery.

Optimizing Visualization in Endoscopic Spine Surgery

Given the inherent limitations of spinal endoscopic surgery, proper lighting and visualization are of tremendous importance. These limitations include a small field of view, significant potential for disorientation, and small working cannulas. While modern endoscopic surgery has evolved in spite of these shortcomings, further progress in improving and enhancing visualization must be made to improve the safety and efficacy of endoscopic surgery. However, in order to understand potential avenues for improvement, a strong basis in the physical principles behind modern endoscopic surgery is first required. Having established these principles, novel techniques for enhanced visualization can be considered. Most compelling are technologies that leverage the concepts of light transformation, tissue manipulation, and image processing. These broad categories of enhanced visualization are well established in other surgical subspecialties and include techniques such as optical chromoendoscopy, fluorescence imaging, and 3-dimensional endoscopy. These techniques have clear applications to spinal endoscopy and represent important avenues for future research.

Scientific View on Endoscopic Spine Surgery: Can Spinal Endoscopy Become a Mainstream Surgical Tool?

With the health care environment becoming increasingly patient centric and cost-conscious, interest levels in spinal endoscopy are at an all-time high. Patient demand for the least invasive procedures combined with surgeon desire to maximally shorten the postoperative recovery period has further driven this surgical evolution. Mounting scientific evidence demonstrates the noninferiority and perhaps even superiority of endoscopic techniques to more conventional spinal surgery for the treatment of spinal stenosis and disc herniations. Although higher level evidence is much needed to support the clinical utility of the latest endoscopic techniques and surgical indications, it appears that the entrance of spinal endoscopy into the mainstream arena of spinal surgery is inevitable.

Treatment of penetrating trauma to the buttock assisted by spinal endoscopy

Objective

Penetrating trauma to the buttock is relatively common. Because of the location of the trauma and complicated peripheral anatomical structures, surgery to the area can be difficult. We report the cases of 2 patients who sustained penetrating trauma to the buttock and underwent operative treatment assisted by spinal endoscopy.

Methods

With the rapid development of minimally invasive spine surgery techniques in recent years, especially the wide application of endoscopy, we treated 2 cases of penetrating trauma with endoscopic probing within the wound channel, followed by hemostasis and postoperative irrigation and drainage.

Results

Drainage tubes were removed from the 2 patients within 7 days after the surgery. Their wounds were healing well and they were discharged from the hospital within 12 days.

Conclusions

If there is no injury to the large blood vessels, intestines, or urinary system, satisfactory clinical results can be obtained using spinal endoscopy to probe, irrigate, and identify foreign objects, when combined with hemostasis, postoperative short-term irrigation and debridement, and the use of antibiotics.

The Role of Flexible Neuroendoscopy in Spinal Neurocysticercosis: Technical Note and Report of 3 Cases

BACKGROUND

Neurocysticercosis, caused by the larval form of the tapeworm Taenia solium, is the most common parasitic disease affecting the human central nervous system. The incidence of spinal neurocysticercosis in endemic regions ranges from 0.25% to 5.85%. Surgery is preferred when medical treatment fails to achieve control of the symptoms or when multiple cysts are present.

METHODS

We describe the use of spinal flexible endoscopy for patients with spinal neurocysticercosis who failed to achieve control with standard treatment. Three patients with limb weakness and pain underwent a midline interspinous approach at the L5-S1 level to access the lumbar cistern. The flexible endoscope was introduced, the subarachnoid space was inspected, and the cysticerci were extracted. In 1 patient with cervical subarachnoid blockage, a 3-cm suboccipital craniotomy and removal of the posterior arch of C1 were performed to place a subarachnoid-to-subarachnoid catheter going from the craniocervical junction to the thoracic region.

RESULTS

Removal of the cysticerci was possible in all cases. No complications related to the surgery were observed. All patients received medical treatment for 2-3 months, and all symptoms were solved.

CONCLUSIONS

Flexible spinal endoscopy is a feasible and valuable tool in patients with spinal neurocysticercosis that do not respond adequately to standard treatment. It helps restore cerebrospinal fluid dynamics and can be used to place shunt catheters under guided vision. Longer endoscopes are needed to explore the entire spinal subarachnoid space with a single approach, and more research in this area is needed.

Step-by-Step Sublaminar Approach With a Newly-Designed Spinal Endoscope for Unilateral-Approach Bilateral Decompression in Spinal Stenosis

OBJECTIVE

Spinal stenosis is increasingly common due to population aging. In elderly patients with lumbar central canal stenosis (LCCS), minimizing muscle damage and bone resection is particularly important. We performed a step-by-step operation with a newly designed spinal endoscope to obtain adequate decompression in patients with spinal stenosis.

METHODS

From April 2015 to August 2016, 78 patients (48 males, 30 females) with LCCS (91 segments) underwent endoscopic decompression using a newly designed endoscope system. The inclusion criteria were: (1) neurogenic intermittent claudication with or without radiculopathy, (2) LCCS, and (3) having exhausted conservative treatment (>3 months). The exclusion criteria were: (1) >10° of instability, (2) spondylolisthesis grade II or greater according to the Meyerding criteria, (3) foraminal stenosis, (4) vascular intermittent claudication, (5) infection, and (6) stenosis combined with malignancy. We performed a step-by-step procedure using a newly designed endoscope system for unilateral-approach bilateral decompression. We used the same incision for 2-3 segments, only moving the skin.

RESULTS

The mean follow-up was 2.3±1.3 years. Excellent or good results were found according to the MacNab criteria in 85.9% of cases (67 of 78). The visual analogue scale, Japanese Orthopedic Association score, and Oswestry Disability Index showed significant decreases at 1 month, persisting until the 2-year follow-up. Dural tear occurred in 4 cases (5.1%), and patch repair was performed under endoscopy. No patients experienced aggravated instability requiring surgery.

CONCLUSION

We obtained good results with endoscopic decompression surgery using a newly designed instrument that minimized muscle and bone damage in elderly patients with spinal stenosis.

A Review of Minimally Invasive Surgical Techniques for the Management of Thoracic Disc Herniations

Thoracic disc herniation (TDH) is a rare, but technically challenging, disorder. Apart from their unfamiliarity with this condition, surgeons are often posed with challenges regarding the diverse methods available to address TDH, the neurological disturbances accompanying the disorder, the prospect of iatrogenic cord damage during surgical procedures, and the complications associated with various surgical approaches. In today's era, when minimally invasive surgery has been incorporated into almost every aspect of managing spine disorders, it is necessary for surgeons to be aware of the various minimally invasive techniques available for the management of these rare and difficult conditions. In this review article, we provide a synopsis of the epidemiology, clinical features, and technical aspects of TDH, starting from level identification to intraoperative neuromonitoring and including important steps and guidance for all the minimally invasive approaches to TDH. We conclude the review by providing insights into the clinical decision-making process and outline the specific aspects of "giant" thoracic discs and indications for fusion in certain conditions. Outcomes of minimally invasive surgery for these conditions are generally favorable. The location of herniation is an important factor for surgical planning.

"Microendoscopic" versus "pure endoscopic" surgery for spinal intradural mass lesions: a comparative study and review

BACKGROUND CONTEXT

Endoscopy is increasingly being used for minimal invasiveness and panoramic visualization, with unclear efficacy and safety among spinal intradural mass.

OBJECTIVE

The present study aims to compare microendoscopic and pure endoscopic surgery for spinal intradural lesions.

MATERIALS AND METHODS

Spinal intradural lesions operated using endoscopic or access ports were categorized into "microendoscopic" (predominant microscope use) or "pure endoscopic" (stand-alone endoscopy) surgery, and were studied with respect to clinico-radiological features, techniques, perioperative course, histopathology, clinical, and radiological outcome at minimum of 3 months.

RESULTS

Among 34 patients studied, the initial 15 had "microendoscopic" surgery, 16 had "pure-endoscopic" surgery, and 3 had "mixed" use. There were 18 nerve sheath tumors, 6 meningiomas, 6 cysts, 2 ependymomas, ranging in size from 1.5 to as large as 6.8 cm (21%≥4 cm), including 4 in craniovertebral junction (CVJ). Intermuscular or paraspinous approach was utilized, followed by small bony fenestration or interlaminar corridor. Even larger tumors could be excised using expandable ports or "sliding delivery" technique. Although visualization of sides and angles was better with endoscope, hemostasis and dural closure had steep learning curve, necessitating the use of microscope in the initial cases. Clinical improvement and radiological resolution could be achieved in all. There was no significant difference between the groups. The change in Nurick grade had significant correlation with only the dimension of lesion (p=.03) and preoperative grade (p=.05).

CONCLUSIONS

This is probably the first report of spinal endoscopy for intradural tumors in CVJ or as big as 7 cm. Endoscopy is effective and safe for even large tumors with better visualization of sides and angles, albeit with hemostasis and dural closure having initial learning curve. Wide heterogeneity of surgical terminologies in the literature on these procedures warrants consensus for uniform reporting.

Percutaneous Fully Endoscopic İnterlaminar Approach to the Filum Terminale: A Cadaveric Study

OBJECTIVE

To investigate the utility, safety, and feasibility of a novel endoscopic technique for the visualization and surgical manipulation of the filum terminale in fresh postmortem adult human cadavers.

METHODS

The filums from 18 fresh postmortem adult human cadavers were explored with a percutaneous fully endoscopic interlaminar approach. After the filum was identified and the nerve roots were dissected away from it, the filum was cut. A specimen was sent for histopathologic examination.

RESULTS

In 15 of 18 (83%) cadavers, the filum terminale could be visualized. A specimen for histopathologic examination was obtained from 11 of 15 (73%) visualized filums. Histopathologic examination revealed that 2 of them were fatty filums, 7 were normal filums, and 2 were peripheral nerves.

CONCLUSIONS

We have described a successful and feasible percutaneous fully endoscopic interlaminar approach to the filum terminale. This technique provides a smaller skin incision, narrow durotomy, and minimal tissue damage. Animal studies are necessary to prove the feasibility and safety of our method before clinical use.