Full-endoscopic anterior decompression versus conventional anterior decompression and fusion in cervical disc herniations

Less Is More: Evaluating the Benefits of Minimally Invasive Spinal Surgery

This review aims to explore the evolution, techniques, and outcomes of minimally invasive spine surgery (MISS) within the field of neurosurgery. We sought to address the increasing burden of spine degeneration in a rapidly aging population and the need for optimizing surgical management. This review explores various techniques in MISS, drawing upon evidence from retrospective studies, case series, systematic reviews, and technological advancements in neurosurgical spine treatment. Various approaches, including endonasal cervical, transoral cervical, transcervical, mini-open/percutaneous, tubular, and endoscopic techniques, provide alternatives for current approaches to a range of spinal pathologies. The main findings of this review highlight potential advantages of MISS over traditional open surgery, including reduced complications, shorter hospital stays, and improved patient outcomes. Our research underscores the importance of adopting MISS techniques to optimize patient care in neurosurgical spine treatment.

C7-T1 Full-Endoscopic Posterior Foraminotomy and Sequestrectomy Using Navigation

The main objective of this case and video is to demonstrate the surgical technique of navigated full-endoscopic decompression and sequestrectomy at the C7-T1 level to alleviate C8 nerve root compression and manage cervicobrachialgia. Cervicobrachialgia resulting from C7-T1 disc herniation is a quite rare yet painful condition that can significantly impair motor function in the upper limb. Traditionally, open surgeries can be invasive, with prolonged recovery times and/or fusion of the level with adjacent segment disease. Posterior full-endoscopic approach offers a minimally invasive alternative that allows for quicker recovery, less postoperative pain, and improved outcomes. By preserving motion, it also prevents adjacent segment disease. A 72-year-old female presented with sudden-onset cervicobrachial pain radiating to the ulnar side of the right arm, coupled with paresthesia and weakness of the flexors/interosseous muscles (Medical Research Council=M3). Magnetic resonance imaging confirmed a large right-sided C7-T1 disc herniation compressing the C8 nerve root. A full-endoscopic C7-T1 posterior foraminotomy and sequestrectomy was performed with navigation. The patient experienced immediate relief from pain and improved motor function in the right hand postoperatively. Posterior full-endoscopic foraminotomy and sequestrectomy of the C7-T1 disc herniation is effective for treating cervicobrachialgia due to C8 nerve compression. The minimally invasive approach demonstrated in this video highlights the technique and stresses the advantage of navigation in the lower cervical spine.

Full-Endoscopic Anterior Cervical Decompression and Fusion for Cervical Myelopathy

This article aims to introduce a novel full-endoscopic anterior cervical discectomy and fusion (ACDF) procedure to treat cervical myelopathy. Adoption of endoscopic anterior cervical procedures has been lagging due to safety concerns and the necessity of placing an interbody cage. We have developed novel instrumentation and a modified percutaneous anterior cervical approach that allows a safe and reproducible full-endoscopic ACDF. Specially designed retractor blades facilitate percutaneous placement of a zero-profile cervical interbody cage. A 64-year-old male patient presents with chronic neck pain and bilateral paresthesia in his upper extremities, mild ataxia, and positive Hoffmann sign. He has a history of deep vein thrombosis 5 years prior. Preoperative magnetic resonance imaging and computed tomography scans show a degenerated disk, severe central canal stenosis with cord compression and a hyperintense cord signal at C5-6, compatible with cervical myelopathy. An electromyography of upper extrimities shows suspicion of myelopathy at C5-6. Full-endoscopic ACDF was performed at C5-6 to decompress the canal and restore disk height with a zero-profile interbody cage. Postoperatively the patient showed improvement of his symptoms with reduced pain and disability scores and was discharged from the hospital within 24 hours of the surgery. Outcome is satisfactory at 2-year postoperative follow-up. Full-endoscopic ACDF enables excellent visualization of the posterior endplates and cervical canal with constant irrigation, facilitating treatment of cervical myelopathy. No retraction is required during discectomy and decompression, decreasing the risk of postoperative dysphagia, hoarseness and bleeding. A zero-profile interbody cage can be percutaneously placed with special retractor blades.

Evaluating the effectiveness of the transcorporeal approach in minimally invasive spine surgery for cervical spinal disease: a comprehensive review and technical insights

BACKGROUND

The evolution of minimally invasive spine surgery, propelled by microscopy and endoscopy techniques, has reshaped the landscape of spinal interventions. The anterior approach to the cervical spine is widely recognized for its reproducibility and effectiveness in treating pathologies leading to radiculopathy or myelopathy. Apart from the traditional transdiscal approach, this study delves into the anterior transcorporeal approach, a minimally invasive technique, exploring its applicability in various cervical spinal pathologies.

PURPOSE

The objective is to comprehensively illustrate the anterior transcorporeal approach, exploring its historical development, biomechanical underpinnings, technical nuances, and clinical applications in managing cervical spine disorders.

METHODS

We conducted a comprehensive review using PubMed, Embase, Cochrane Library, and Web of Science, adhering to PRISMA guidelines. The search was focused on the minimally invasive anterior transcorporeal approach for cervical pathologies, with an emphasis on evaluating the methodological evolution, technical execution, and clinical outcomes across diverse studies.

RESULTS

The review identified a significant body of literature supporting the efficacy of the minimally invasive anterior transcorporeal approach. Over the past two decades, this approach has demonstrated encouraging clinical outcomes, suggesting its potential as an alternative strategy for specific cervical spine diseases. The evolution of this technique is tightly linked to the advancements in medical equipment and the innovative endeavors of surgical pioneers.

CONCLUSIONS

The anterior transcorporeal approach marks a milestone in minimally invasive cervical spine surgery. Its development reflects ongoing efforts to refine surgical techniques for better patient outcomes. While offering a promising alternative for treating certain cervical spine conditions, the approach demands precise case selection and is influenced by the rapid progression of medical technology. Future research and technological advancements are expected to further enhance the efficacy and safety of this approach, potentially expanding its indications in spinal surgery.

Anterior percutaneous full-endoscopic transcorporeal decompression for cervical disc herniation: a finite element analysis and long-term follow-up study

OBJECTIVE

The purpose of this study was to investigate the long-term consequences on the cervical spine after Anterior transcorporeal percutaneous endoscopy cervical discectomy (ATc-PECD) from the biomechanical standpoint.

METHODS

A three-dimensional model of the normal cervical spine C2-T1 was established using finite element method. Subsequently, a disc degeneration model and degeneration with surgery model were constructed on the basis of the normal model. The same loading conditions were applied to simulate flexion, extension, lateral bending and axial rotation of the cervical spine. We calculated the cervical range of motion (ROM), intradiscal pressure, and intravertebral body pressure under different motions for observing changes in cervical spine biomechanics after surgery. At the same time, we combined the results of a long-term follow-up of the ATc-PECD, and used imaging methods to measure vertebral and disc height and cervical mobility, the Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) score were used to assess pain relief and neurological functional recovery.

RESULTS

The long-term follow-up results revealed that preoperative JOA score, neck VAS score, hand VAS score, IDH, VBH, and ROM for patients were 9.49 ± 2.16, 6.34 ± 1.68, 5.14 ± 1.48, 5.95 ± 0.22 mm, 15.41 ± 1.68 mm, and 52.46 ± 9.36° respectively. It changed to 15.71 ± 1.13 (P < 0.05), 1.02 ± 0.82 (P < 0.05), 0.77 ± 0.76 (P < 0.05), 4.73 ± 0.26 mm (P < 0.05), 13.67 ± 1.48 mm (P < 0.05), and 59.26 ± 6.72° (P < 0.05), respectively, at 6 years postoperatively. Finite element analysis showed that after establishing the cervical spondylosis model, the overall motion range for flexion, extension, lateral bending, and rotation decreased by 3.298°, 0.753°, 3.852°, and 1.131° respectively. Conversely, after establishing the bone tunnel model, the motion range for these actions increased by 0.843°, 0.65°, 0.278°, and 0.488° respectively, consistent with the follow-up results. Moreover, analysis of segmental motion changes revealed that the increased cervical spine mobility was primarily contributed by the surgical model segments. Additionally, the finite element model demonstrated that bone tunneling could lead to increased stress within the vertebral bodies and intervertebral discs of the surgical segments.

CONCLUSIONS

Long-term follow-up studies have shown that ATc-PECD has good clinical efficacy and that ATc-PECD can be used as a complementary method for CDH treatment. The FEM demonstrated that ATc-PECD can lead to increased internal stresses in the vertebral body and intervertebral discs of the operated segments, which is directly related to cervical spine degeneration after ATc-PECD.

Disc Height and Angle Changes on Radiographs and Magnetic Resonance Imaging after Anterior or Posterior Percutaneous Endoscopic Cervical Discectomy

Objectives: Cervical disc herniation (CDH) leads to pain, numbness, and potential disability. Percutaneous endoscopic cervical discectomy (PECD) offers an anterior or posterior approach. This study aims to compare postoperative disc height and angle changes one year after PECD, considering both approaches. Methods: We retrospectively reviewed the data from patients with CDH who underwent PECD from October 2017 to July 2022. Cervical disc height was measured using the preoperative and one-year postoperative magnetic resonance imaging (MRI) examinations. Lordotic angle (LA), global alignment angle (GAA), segmental alignment angle (SAA), and slippage distance (SD) at the surgical level were measured on radiographs in the neutral, flexion, and extension positions. Results: Thirty-eight patients who underwent posterior PECD (PPECD) and five patients who underwent anterior PECD (APECD) were included in the evaluation. The mean age of the patients was 47.4 years (range: 29-69 years). There was a significant difference in the preoperative and one-year postoperative GAA and SAA in extension in the PPECD group (p = 0.003 and 0.031, respectively). The mean decreased disc height one-year postoperative was 1.30 mm in the APECD group and 0.3 mm in the PPECD group by MRI. A significant disc height decrease was observed in the APECD group (p < 0.001). Conclusions: Treating CDH with PPECD or APECD is feasible, as it can relieve symptoms and reduce disability. Stability remained unaffected during the first year after surgery, even though there was an increase in angulation during extension. Despite a significant decrease in disc space following APECD, patients reported significant symptom improvement and no new symptoms.

Evolution, Current Trends, and Latest Advances of Endoscopic Spine Surgery

Background: The aging of the population in developing and developed countries has led to a significant increase in the health burden of spinal diseases. These elderly patients often have a number of medical comorbidities due to aging. The need for minimally invasive techniques to address spinal disorders in this elderly population group cannot be stressed enough. Minimally invasive spine surgery (MISS) has several proven benefits, such as minimal muscle trauma, minimal bony resection, lesser postoperative pain, decreased infection rate, and shorter hospital stay. Methods: A comprehensive search of the literature was performed using PubMed. Results: Over the past 40 years, constant efforts have been made to develop newer techniques of spine surgery. Endoscopic spine surgery is one such subset of MISS, which has all the benefits of modern MISS. Endoscopic spine surgery was initially limited only to the treatment of lumbar disc herniation. With improvements in optics, endoscopes, endoscopic drills and shavers, and irrigation pumps, there has been a paradigm shift. Endoscopic spine surgery can now be performed with high magnification, thus allowing its application not only to lumbar spinal stenosis but also to spinal fusion surgeries and cervical and thoracic pathology as well. There has been increasing evidence in support of these newer techniques of spine surgery. Conclusions: For this report, we studied the currently available literature and outlined the historical evolution of endoscopic spine surgery, the various endoscopic systems and techniques available, and the current applications of endoscopic techniques as an alternative to traditional spinal surgery.

Anterior Percutaneous Full-Endoscopic Transcorporeal with Single-Incision Treatment for Noncontiguous 2-Level Cervical Disc Herniation: Technical Report and Early Follow-Up

BACKGROUND

Noncontiguous 2-level cervical disc herniation (NCT-CDH) is a common condition that often requires surgical intervention. In this study, we developed a surgical approach for the treatment of NCT-CDH using anterior percutaneous full-endoscopic single incision through the vertebral body. We provide a brief overview of its safety, efficacy, and feasibility, along with a description of our relevant surgical experience.

METHODS

A retrospective study was conducted, involving 30 patients who were followed up for at least 12 months. Preoperative and postoperative visual analog scale, Japanese Orthopedic Association scores, Nurick scores, intervertebral disc height, and modified Macnab criteria were recorded. Patients underwent regular radiological evaluations throughout the follow-up period.

RESULTS

Postoperative computed tomography, magnetic resonance imaging, and X-ray examinations revealed bone tunnel healing, intact drilled vertebral bodies without collapse, adequate decompression of the spinal canal, and normal cervical mobility. There was a significant improvement in postoperative visual analog scale, Japanese Orthopedic Association scores, Nurick scores, and modified Macnab criteria compared to the preoperative values (P < 0.05).

CONCLUSIONS

Our study revealed that the anterior percutaneous full-endoscopic transcorporeal with single-incision treatment for NCT-CDH is a safe and feasible surgical method. Therefore, it can be considered as a viable treatment option for patients with NCT-CDH.

Evolution of Cervical Endoscopic Spine Surgery: Current Progress and Future Directions-A Narrative Review

Cervical endoscopic spine surgery is rapidly evolving and gaining popularity for the treatment of cervical radiculopathy and myelopathy. This approach significantly reduces muscular damage and blood loss by minimizing soft tissue stripping, leading to less postoperative pain and a faster postoperative recovery. As scientific evidence accumulates, the efficacy and safety of cervical endoscopic spine surgery are continually affirmed. Both anterior and posterior endoscopic approaches have surfaced as viable alternative treatments for various cervical spine pathologies. Newer techniques, such as endoscopic-assisted fusion, the anterior transcorporeal approach, and unilateral laminotomy for bilateral decompression, have been developed to enhance clinical outcomes and broaden surgical indications. Despite its advantages, this approach faces challenges, including a steep learning curve, increased radiation exposure for both surgeons and patients, and a relative limitation in addressing multi-level pathologies. However, the future of cervical endoscopic spine surgery is promising, with potential enhancements in clinical outcomes and safety on the horizon. This progress is fueled by integrating advanced imaging and navigation technologies, applying regional anesthesia for improved and facilitated postoperative recovery, and incorporating cutting-edge technologies, such as augmented reality. With these advancements, cervical endoscopic spine surgery is poised to broaden its scope in treating cervical spine pathologies while maintaining the benefits of minimized tissue damage and rapid recovery.

Anterior Full-endoscopic Single-port Double Transcorporeal Spinal Cord Decompression for Noncontinuous Two-segment Cervical Spondylotic Myelopathy: A Technical Note

OBJECTIVE

In clinical practice, noncontinuous two-segment spinal cord cervical spondylosis is a particular form of cervical degenerative disease. Traditional anterior open surgery frequently comes with severe trauma, risks, and debatable treatment options. This study aimed to describe for the first time a novel minimally invasive technique, namely, anterior full-endoscopic single-port double transcorporeal spinal cord decompression for the treatment of patients with noncontinuous two-segment cervical spondylotic myelopathy.

METHOD

From February 2020 to May 2021, five patients with noncontinuous two-segment cervical spondylotic myelopathy were treated with anterior full-endoscopic single-port double transcorporeal spinal cord decompression. Two bone channels were established by the trephine through the vertebral body oblique upward and downward to the herniated disc osteophyte complex, and the full-endoscopic system could decompress the spinal cord through the channels. All cases were followed up for over 2 years. The modified Japanese Orthopaedic Association (mJOA) score and visual analogue scale (VAS) score before and after operation and during follow-up were used to evaluate the clinical effectiveness. Radiological examinations, including CT and MRI, were utilized to evaluate the efficacy of spinal cord decompression and bone channel repair.

RESULTS

All operations were successfully completed and the average operation time was 185 min, with no operation-related complications. Compared with the preoperative evaluation, the mJOA score and VAS score were improved at each time point after operation and follow-up. Postoperative CT and MRI scans showed that the intervertebral disc-osteophyte complex was removed through the vertebral bone passage, and the spinal cord was fully decompressed. After 24 months of follow-up, CT and MRI scans showed that the bone channel was almost repaired and healed.

CONCLUSION

Anterior full-endoscopic single-port double transcorporeal spinal cord decompression is an effective minimally invasive technique for noncontinuous two-segment cervical spondylosis. It provides precise and satisfactory spinal cord decompression under endoscopic visualization with minimum trauma.

Surgical Essentials and 2-Year Follow-Up Results of Channel Repair in Endoscopic Transcorporeal Discectomy for Cervical Disc Herniation

OBJECTIVE

To evaluate long-term outcomes and surgical essentials of channel repair in endoscopic transcorporeal discectomy for cervical disc herniation.

METHODS

From October 2019 to March 2020, 24 patients with cervical disc herniation underwent channel repair after percutaneous full-endoscopic anterior transcorporeal cervical discectomy. Five interventions were performed at C3-C4, 11 were performed at C4-C5, and 8 were performed at C5-C6. Clinical outcomes were evaluated by Neck Disability Index, Japanese Orthopaedic Association, and visual analog scale scores. Radiologic changes were evaluated with intervertebral disc height and drilled vertebral height.

RESULTS

All procedures were completed with a mean operating time of 86.40 ± 8.19 minutes. Swollen neck was observed in 5 patients, which resolved within 2 hours. At the final follow-up, Neck Disability Index, Japanese Orthopaedic Association, and visual analog scale scores were improved significantly compared with preoperative assessments (P < 0.05); intervertebral disc height was decreased significantly (P < 0.05); and loss of drilled vertebral height was not significant (P > 0.05). All 24 bony channels disappeared by 3 months postoperatively. No other complications were observed.

CONCLUSIONS

Percutaneous full-endoscopic anterior transcorporeal cervical discectomy with channel repair offers a minimally invasive and effective treatment option for patients with cervical disc herniation. This technique demonstrates favorable clinical outcomes, including preservation of cervical spine mobility and minimal complications. Although there was a significant loss of intervertebral disc height, no vertebral collapse occurred. Strict adherence to surgical indications and precautions is crucial for successful outcomes. Further research and long-term studies are required to validate the efficacy and safety of this approach in a larger patient population.

Percutaneous Fully-endoscopic Anterior Transcorporeal Procedure for the Treatment of Isolated Ossification of the Posterior Longitudinal Ligament in the Cervical Spine: A Case Report

BACKGROUND

With the development of spinal endoscopic techniques, on the basis of our previous experience in treating various types of cervical disc herniation with this endoscopic technique, we took the lead in applying the percutaneous fully endoscopic anterior transcorporeal procedure to be utilized in the treatment of the isolated cervical ossification of the posterior longitudinal ligament (OPLL).

CASE PRESENTATION

A 66-year-old male patient who weighed 57 kg, with a height of 169 cm was admitted to the hospital on September 16, 2021 because of recurrent pain and numbness in the neck, shoulder, and right arm for 2 years, which as aggravated for the last 2 weeks. Two years ago, the patient developed neck and shoulder pain accompanied by right arm pain without obvious predisposing factors, and numbness in the first web space of the right hand. In the last 2 weeks, he had difficulty moving the right arm, but no pain or numbness in the contralateral arm. MRI and CT scans demonstrated that the ossified posterior longitudinal ligament of the cervical 5/6 vertebrae with spinal canal stenosis and seriously compressed the spinal cord patient was treated with a percutaneous fully endoscopic anterior transcorporeal procedure.

CONCLUSION

Our percutaneous fully endoscopic anterior transcorporeal procedure is a feasible, minimally invasive surgery for treating isolated ossification of the posterior longitudinal ligament in the cervical spine.

Complications of Cervical Endoscopic Spinal Surgery: A Systematic Review and Narrative Analysis

BACKGROUND

There are no systematic evidence-based medical data on the complications of endoscopic cervical spinal surgery. This narrative analysis compiled data from various studies that examined endoscopic complications, such as cervical disc herniation and foraminal stenosis. This study aimed to investigate the efficacy and safety of endoscopic surgery in cervical radiculopathy.

METHODS

We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and keywords were set as "endoscopic cervical spinal surgery", "endoscopic cervical discectomy", "endoscopic cervical foraminotomy", and "percutaneous endoscopic cervical discectomy". We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic cervical surgery was divided into three categories: full endoscopic anterior, endoscopic posterior, and unilateral biportal approaches. We excluded duplicate publications, studies without full text, studies without complications or incomplete information, and studies that did not provide the necessary data for extraction, animal experiments, or reviews.

RESULTS

Difficulties in swallowing, hematoma, and hoarseness are common complications associated with the anterior cervical approach. In contrast, complications of the posterior approach include nerve root injury, hematoma, and dysesthesia. However, endoscopic cervical spinal surgery, including the full endoscopic anterior, posterior, and unilateral biportal approaches, is a safe and effective treatment for cervical radiculopathy.

CONCLUSIONS

Complications of full endoscopic cervical spinal surgery differ significantly depending on the anterior and posterior approaches. In the anterior approach, swallowing difficulty, recurrent disc, hematoma, and dysphonia are the common complications. In contrast, transient dysesthesia, dural tears, upper limb motor deficits, and persistent arm pain are commonly reported with the posterior approach.

Classification of cervical disc herniation myelopathy or radiculopathy: a magnetic resonance imaging-based analysis

Background

Preoperative magnetic resonance imaging (MRI) can clearly show the location and level of disc herniation. When the symptoms are consistent with the Prominent segments, surgical treatment can be indicated. However, the varied extents of the protruding masses in cervical disc herniation (CDH) have been rarely reported. This study aimed to characterize the severity of CDH and to develop a reproducible grading and zoning system for cervical disc degeneration.

Methods

A total of 200 patients who presented with single CDH and underwent MRI/computed tomography (CT) scans were enrolled in this prospective study between 2018 and 2021. A total of 170 cervical discs were graded according to MRI by 3 spine surgeons in a blinded fashion. CDHs were graded 1-3, with regions A-C. All patients with grade 1 and mild C symptoms were excluded. The foramen facet spinal (FFS) classification based on MRI Japanese Orthopedic Association (JOA) scores and the incidence of complications were evaluated and analyzed, and follow-up outcomes were assessed.

Results

Areas 2-A, 2-B, and 1-C had high motor function scores, areas 2-A, 3-A, and 2-AB had high sensory scores, but areas 3-AB and 3-A had low bladder function scores. Areas 3-AB had the most severe symptoms and the lowest scores. Area 1-C showed neurogenic abnormal sensation and higher visual analog scale (VAS) scores. A good/excellent outcome as indicated by the JOA score was 94.70% at 3 months and 92.35% at 1 year in 170 patients. The complication rate was 9.41%. The diagnostic coefficient of the FFS classification was 0.888, P<0.001.

Conclusions

The FFS classification is an objective scoring system that can be applied similarly by multiple examiners and is correlated with clinical symptoms.

Current Indications for Spinal Endoscopic Surgery and Potential for Future Expansion

Endoscopic spine surgery (ESS) has evolved as a safe, effective, and efficient alternative for minimally invasive spine surgery (MISS). The innovation of full-endoscopic systems makes definitive decompression surgery through different approaches feasible. The approach can be determined according to the location of the target lesion or the surgeon's preference. During the past 2 decades, ESS has expanded its indications from lumbar to cervical spines. Except for decompression, endoscopy-assisted fusion surgery is also developing. However, ESS is still evolving and has a steep learning curve. The revolution of technologies and ESS techniques will enable surgeons to treat various spinal diseases more practically. In recent years, the application of the computer-assisted navigation system and augmented reality have reformed imaging quality and interpretation. The endoscopic rhizotomy techniques have opened a new way for MISS of chronic low back pain. This review introduces the current indications of ESS and its potential future expansion.

Anterior Endoscopic Cervical Discectomy: Surgical Technique and Literature Review

The conventional surgical technique for radiculopathy with cervical disc herniation (CDH) is anterior cervical discectomy and fusion, with a good clinical outcome and fusion rate. However, significant perioperative morbidity related to extensive surgical exposure has been reported. Therefore, anterior endoscopic cervical discectomy (AECD) using a working channel endoscope has been developed to reduce surgical complications and tissue damage. The objective of this study was to describe a cutting-edge technique for AECD of soft CDH. The primary indication is cervical radiculopathy with or without axial neck pain due to soft CDH. The surgical procedure consists of 2 parts: (1) a safe anterior percutaneous approach under fluoroscopic control and (2) selective endoscopic discectomy and foraminal decompression using specialized mechanical tools under endoscopic visualization. The clinical outcomes are comparable to those of conventional surgery and show the benefits of minimally invasive spine procedure. Perioperative data revealed typical minimalism, including reduced muscle damage, blood loss, operative time, and recovery time. With technical advancements in surgical instruments and optics, AECD will become more practical and safer. AECD is effective in selected CDH cases with cervical radiculopathy. However, high-quality clinical studies are needed to verify the effectiveness of this endoscopic cervical spinal procedure.

Complications and Management of Endoscopic Spinal Surgery

In the past, the use of endoscopic spine surgery was limited to intervertebral discectomy; however, it has recently become possible to treat various spinal degenerative diseases, such as spinal stenosis and foraminal stenosis, and the treatment range has also expanded from the lumbar spine to the cervical and thoracic regions. However, as endoscopic spine surgery develops and its indications widen, more diverse and advanced surgical techniques are being introduced, and the complications of endoscopic spine surgery are also increasing accordingly. We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and key words were set as “endoscopic spinal surgery,” “endoscopic cervical foramoinotomy,” “PECD,” “percutaneous transforaminal discectomy,” “percutaneous endoscopic interlaminar discectomy,” “PELD,” “PETD,” “PEID,” “YESS” and “TESSYS.” We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic lumbar surgery was divided into full endoscopic interlaminar and transforaminal approaches and a unilateral biportal approach. We performed a comprehensive review of available literature on complications of endoscopic spinal surgery. This study particularly focused on the prevention of complications. Regardless of the surgical methods, the most common complications related to endoscopic spinal surgery include dural tears and perioperative hematoma. transient dysesthesia, nerve root injury and recurrence. However, Endoscopic spinal surgery, including full endoscopic transforaminal and interlaminar and unilateral biportal approaches, is a safe and effective a treatment for lumbar as well as cervical and thoracic spinal diseases such as disc herniation, lumbar spinal stenosis, foraminal stenosis and recurrent disc herniation.

Bibliographic Study and Meta-Analysis of Clinical Outcomes of Full-Endoscopic Spine Surgery for Painful Lumbar Spine Conditions

BACKGROUND

Full-endoscopic spine surgery (FESS) indications already cover degenerative, infectious, and neoplastic diseases. This study aimed to use a bibliometric search and meta-analysis of the highest-quality studies in the last 20 years to determine the quantity and quality of FESS research, geographic distribution, and the outcomes for lumbar conditions.

METHODS

Articles on FESS published from 2000 to 2022 were screened and assessed through Web of Science, PubMed, and Scopus. Also, databases were searched for longitudinal studies to pool in a meta-analysis of patients undergoing FESS for lumbar conditions. After stratifying the risk of bias and having collected the studies of the highest quality, we included the proportion of patients with a satisfactory outcome and intraoperative and postoperative adverse events after the analysis of lumbar spine conditions.

RESULTS

A total of 728 articles were identified by the bibliographic search. Between 2000 and 2021, the published articles increased 21-fold. Most were from China (70.15%), followed by South Korea (19.5%). Most were retrospective (68.3%) and regarding treatment of lumbar disease (86.4%). Fifty studies, including 34,828 patients, were pooled in the meta-analysis. More than 85% of patients experienced satisfactory improvement in each of different lumbar conditions. Major adverse events were <2%; recurrence and postoperative dysesthesia rates were within those reported for open or mini-invasive procedures.

CONCLUSIONS

This study may fill research gaps on FESS and lead to adequately designed studies. Our meta-analysis showed that FESS for lumbar diseases is a procedure with satisfactory outcomes and low rates of adverse events.

Percutaneous Full Endoscopic Management of Spinal Foraminal Schwannomas: Case Series

BACKGROUND

Schwannoma, a benign peripheral nerve sheath tumor, is perhaps only secondary to degenerative pathology as the most common lesion at neural foramen. The surgical dilemma here is either risking nerve injury because of inadequate exposure or the need for internal fixation because of facet joint sacrifice.

OBJECTIVE

To evaluate the feasibility and safety of management of foraminal schwannomas by percutaneous full-endoscopic technique.

METHODS

A single-center retrospective review was conducted on patients who underwent full-endoscopic resection of neural foraminal schwannomas. Tumors were grouped into either medial type or lateral type based on relevant location to the neural foramen, and respective surgical approaches were adopted. Data including preoperative neurological status, tumor size, surgery time, the extension of resection, and clinical outcomes were collected. The learning curve was plotted as surgical time/tumor size against case number.

RESULTS

A total of 25 patients were treated between May 2015 and March 2022. Gross total resection was achieved in 24 patients, and near-total resection in 1 case, with 1 patient experienced transient voiding difficulty. No tumor recurrence or spinal instability was detected in the short-term follow-up (median follow-up 22 months, range 3 months-6 years). Surgical efficiency improved with the number of cases operated on and remained stable after the initial 10 cases.

CONCLUSION

Percutaneous full-endoscopic technique is a safe and minimally invasive technique for the resection of foraminal schwannomas.

Comparison of the Short-Term Efficacy of Percutaneous Endoscopic Thoracic Decompression and Laminectomy in the Treatment of Thoracic Ossification of the Ligamentum Flavum

OBJECTIVE

This study aimed to investigate the short-term efficacy of percutaneous endoscopic thoracic decompression (PETD) under local anesthesia and traditional posterior thoracic laminectomy (PTL) in treating single-segment thoracic ossification of the ligamentum flavum (T-OLF).

METHODS

This was a retrospective review of the clinical information of 52 patients with T-OLF between September 2017 and September 2021. Based on the inclusion criteria, a total of 52 patients were included in the present research, 26 in the PETD group and 26 in the PTL group. The general preoperative data, intraoperative surgical conditions, preoperative and postoperative clinical information, and complications were collected. The modified Japanese Orthopedic Association score and recovery rate were evaluated preoperatively and at 3, 6, and 12 months postoperatively.

RESULTS

There was no statistically significant difference in the baseline parameters in either group (P > 0.05). There were statistically significant differences in operation time (94.62 vs. 144.62 minute) and blood loss (22.12 vs. 287.69 mL) between the PETD group and the PTL group. The modified Japanese Orthopedic Association score in the 2 groups improved from (5.46 ± 1.10) and (5.69 ± 1.01) preoperatively to (9.08 ± 0.90) and (8.88 ± 1.07) at 12 months postoperatively. The recovery rate was 84.6% in the PETD group and 76.9% in the PTL group. In addition, the complications in the PETD group were fewer than those in the PTL group.

CONCLUSIONS

The PETD under local anesthesia for T-OLF has many advantages, such as high patient acceptance, good short-term clinical outcomes, and few complications; therefore, this procedure should be promoted as a viable treatment option for T-OLF.

Outcome of Anterior and Posterior Endoscopic Procedures for Cervical Radiculopathy Due to Degenerative Disk Disease: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

Cervical spine endoscopic discectomy and decompression have gained popularity in the last decade. This review aimed to shed light on the current outcomes of cervical spine endoscopic procedures for degenerative disc disease (DDD) and to calculate a pooled estimate of various outcome measures.

METHODS

We retrieved articles published in English related to endoscopic cervical spine procedures from 3 central databases from inception until September 2020. A subgroup analysis based on the anterior versus the posterior approach was performed.

RESULTS

Thirty-one articles fulfilled the eligibility criteria and included 1,410 patients. A successful outcome was observed in 91.3% (88.6-93.4%, P = 0.000). This percentage was lower for the anterior approach (89.6% [85.8-92.5%], P = 0.000) than for the posterior approach (94.2% [90.4-96.5%], P = 0.000). A higher percentage of poor outcomes was reported for the anterior approach (5.7% [3.2-10.1%], P = 0.000 vs. 2.3% [1-5.5%], P = 0.000 for the posterior approach). The overall complication rate was 7.2% (5.2-9.8%, P = 0.000). There was a slightly higher complication rate for the anterior approach (7.9% [4.5-13.3%], P = 0.000) than for the posterior approach (6.7% [4.4-10%], P = 0.000). The revision rate was 4.2% (2.6-6.8%, P = 0.000); and 4.2% (1.8-9.7%, P = 0.000) for the anterior approach and 4.00% (2.2-7.4%, P = 0.000) for the posterior approach.

CONCLUSIONS

There is a higher success rate and lower complication rate with the posterior approach than with the anterior approach. However, high-quality randomized controlled trials are vital to evaluate the efficacy of these procedures.

Comparison of Using Intraoperative Computed Tomography-Based 3-Dimensional Navigation and Fluoroscopy in Anterior Cervical Diskectomy and Fusion for Cervical Spondylosis

OBJECTIVE

Anterior cervical diskectomy and fusion (ACDF) is a highly successful procedure to treat spinal cord or nerve root compression; however, complications can still occur. With advancements in imaging, 3-dimensional (3D) reconstruction allows real-time instrument tracking in a surgical field relative to the patient's anatomy. Here, we compare plate positioning and short-term outcomes when using 3D navigation to fluoroscopy in ACDF for degenerative spine disease.

METHODS

All ACDFs for cervical spondylosis performed by 6 surgeons at a single center between 2010 and 2018 were included. ACDFs were divided into those performed using 3D navigation or fluoroscopy. Records were assessed for patient demographics, American Society of Anesthesiology score, number of operated interspaces, operative time, length of stay, perioperative complications, and 90-day readmissions. Postoperative images were reviewed for lateral and angular plate deviations.

RESULTS

A total of 193 ACDFs performed with 3D navigation and 728 performed with fluoroscopy were included. After controlling for demographics and surgical characteristics, using 3D navigation was associated with less lateral plate deviation (P = 0.048) and longer operative times per interspace (P < 0.001) but was not associated with angular plate deviation (P = 0.724), length of stay (P = 0.393), perioperative complications (P = 0.844), and 90-day readmissions (P = 0.539).

CONCLUSIONS

Using 3D navigation in ACDF for degenerative disease is associated with slightly more midline plate positioning and comparable short-term outcomes as using fluoroscopy and can be a suitable alternative. Advantages of using this technology, such as improved visualization of anatomy, should be weighed against disadvantages, such as increased operative time, on a per-patient basis.

Comparison of percutaneous endoscopic thoracic decompression and posterior thoracic laminectomy for treating thoracic ossification of the ligamentum flavum: a retrospective study

Background

Thoracic spinal stenosis (TSS) caused by ossification of the ligamentum flavum (OLF) is generally treated by surgical decompression. In this study, we compared the efficacy and safety of percutaneous endoscopic thoracic decompression (PETD) and posterior thoracic laminectomy (PTL) for treating thoracic ossification of the ligamentum flavum (TOLF).

Methods

Twenty consecutive patients with TSS caused by TOLF who were treated between April 2016 and May 2020 were included in this retrospective study. They were divided into the PETD (n = 11) and PTL (n = 9) groups. The mean follow-up period was 19.6 months. The visual analogue scale (VAS) score, the modified Japanese Orthopedic Association (mJOA) score and the recovery rate (RR) were used to evaluate the clinical outcomes.

Results

There were significant differences between PETD group and PTL group in operative time (min) (95.0 ± 18.8 vs 131.1 ± 19.0), postoperative drainage (mL) (20.2 ± 7.9 vs 586.1 ± 284.2), hospital stay (days) (4.4 ± 1.2 vs 10.4 ± 2.6) (P < 0.05 for all). However, both groups had similar and significant improvement in VAS and mJOA scores. The RR of two groups achieved the same improvement (81.8% VS 77.8%, P > 0.05).

Conclusions

The use of PETD and PTL for treating TOLF both achieved favorable outcomes. PETD is both minimally invasive and achieves similar postoperative symptom relief to PTL. Therefore, PETD could be considered as an effective alternative to traditional open surgery for TOLF in single-segment lower thoracic spine.

Comparative Analysis of the Biomechanical Characteristics After Different Minimally Invasive Surgeries for Cervical Spondylopathy: A Finite Element Analysis

Minimally invasive surgeries, including posterior endoscopic cervical foraminotomy (PECF), microsurgical anterior cervical foraminotomy (MACF), anterior transdiscal approach of endoscopic cervical discectomy (ATd-ECD), and anterior transcorporeal approach of endoscopic cervical discectomy (ATc-ECD), have obtained positive results for cervical spondylotic radiculopathy. Nonetheless, there is a lack of comparison among them regarding their biomechanical performance. The purpose of this study is to investigate the biomechanical changes of operated and adjacent segments after minimally invasive surgeries compared to a normal cervical spine. A three-dimensional model of normal cervical vertebrae C3–C7 was established using finite element analysis. Afterwards, four surgical models (PECF, MACF, ATd-ECD, and ATc-ECD) were constructed on the basis of the normal model. Identical load conditions were applied to simulate flexion, extension, lateral bending, and axial rotation of the cervical spine. We calculated the range of motion (ROM), intradiscal pressure (IDP), annulus fibrosus pressure (AFP), uncovertebral joints contact pressure (CPRESS), and facet joints CPRESS under different motions. For all circumstances, ATc-ECD was close to the normal cervical spine model, whereas ATd-ECD significantly increased ROM and joints CPRESS and decreased IDP in the operated segment. PECF increased more the operated segment ROM than did the MACF, but the MACF obtained maximum IDP and AFP. Except for ATc-ECD, the other models increased joints CPRESS of the operated segment. For adjacent segments, ROM, IDP, and joints CPRESS showed a downward trend in all models. All models showed good biomechanical stability. With their combination biomechanics, safety, and conditions of application, PECF and ATc-ECD could be appropriate choices for cervical spondylotic radiculopathy.

A Novel Technique of Endoscopic Anterior Transcorporeal Approach with Channel Repair for Adjacent Segment Disease After Anterior Cervical Discectomy and Fusion

OBJECTIVE

To first report the application of percutaneous full-endoscopic anterior transcorporeal cervical discectomy (PEATCD) with channel repair for a patient with adjacent segment disease (ASD) after anterior cervical discectomy and fusion.

METHODS

PEATCD with channel repair was performed for a patient with ASD at the cranial level adjacent to previous fusion at the C5-C6 level. The pre- and postoperative clinical symptoms were evaluated with Japanese Orthopedic Association and visual analog scale (VAS). The radiological examinations included magnetic resonance imaging, computed tomography, and plain radiographs, which were used to evaluate the cervical alignment, stability, intraoperative decompression, and bony channel.

RESULTS

The procedure was successfully completed within 70 minutes. The drainage tube was unnecessary. No surgery-related complications were recorded. The postoperative neck pain immediately improved to VAS 3 from preoperative VAS 6. The Japanese Orthopedic Association scores also took a turn for the better gradually from preoperative 10 to final 16 (improvement rate 85.7%). The muscle power recovered completely, and the Hoffman sign turned to negative during follow-up periods. Magnetic resonance imaging 1 week postoperatively showed a total removal of the herniation. The bony channel was almost disappeared on computed tomography images 3 months postoperatively. During postoperative periods, no relapse, channel collapse, bone plug migration, or instability was observed.

CONCLUSION

As a novel and supplemental procedure for ASD after anterior cervical discectomy and fusion, PEATCD combines the advantages of transcorporeal approach and endoscopy together, which decreases iatrogenic damage to disc, preserves the cervical motion segment, and reduces surgical trauma. As the limitations of 1 case show, the effectiveness and reliability of PEATCD for patients with ASD should be verified in further studies.

Clinical study on the efficacy and safety of percutaneous endoscopic anterior cervical discectomy in the treatment of cervical disc herniation

PURPOSE

To compare the clinical efficacy of anterior percutaneous endoscopic cervical discectomy (APECD) and anterior cervical decompression and fusion (ACDF) in the treatment of cervical disc herniation.

METHODS

A total of 115 cases of cervical disc herniation treated in our hospital from May 2016 to August 2018 were selected. The subjects were divided into APECD and ACDF groups. The operation time, intra-operative blood loss, and hospital stay of the two groups were recorded and compared, and the clinical symptoms were recorded at one week, one year, and two years after the operation. The neck and upper limb visual analog scale (VAS) score, Japanese Orthopedic Association (JOA) score, cervical range of motion (ROM), post-operative cervical lordosis angle and adjacent vertebral body height were compared between the two groups.

RESULTS

All 115 patients underwent successful operations. The intra-operative blood loss and operation time in the APECD group were significantly less than those in the ACDF group (P < 0.05). There were no oesophago-tracheal sheaths, carotid artery sheaths, cervical sympathetic trunks, vertebral artery injuries, or dural tears in the two groups. The JOA and VAS scores of the two groups significantly improved from pre- to post-operatively, but there were no significant differences between the two groups at the last follow-up (P > 0.05). The post-operative radiological results showed that the herniated cervical intervertebral disc was removed completely. One year after the operation, the cervical lordosis angle increased significantly in both groups (P < 0.05). However, ROM decreased significantly in the ACDF group (P < 0.05), and there was no significant change in ROM in the APECD group (P > 0.05). The cervical lordosis angle did not significantly differ between the two groups at the last follow-up (P > 0.05), but there was a significant difference in ROM between the two groups at the last follow-up (P < 0.05). In the ACDF group, the height of the adjacent vertebral body increased 1 year after the operation (P < 0.05). In the APECD group, the height of the adjacent vertebral body decreased one year after the operation, but the value was not significantly different from the pre-operative value (P > 0.05). There was a significant difference in the height of the adjacent vertebral body between the two groups at the last follow-up (P < 0.05). The incidence of post-operative complications did not significantly differ between the two groups (P > 0.05).

CONCLUSION

APECD is a minimally invasive treatment that is safe and effective. The medium- and short-term effects of APECD and ACDF in the treatment of cervical disc herniation are similar. In addition, APECD is superior to ACDF in the operation time, intra-operative blood loss, and ROM. However, prospective, multicenter studies with longer follow-up periods need to be conducted, and the recurrence rate and intervertebral height loss need to be studied.

Intraoperative image guidance for cervical spine surgery

Intraoperative image-guidance in spinal surgery has been influenced by various technological developments in imaging science since the early 1990s. The technology has evolved from simple fluoroscopic-based guidance to state-of-art intraoperative computed tomography (iCT)-based navigation systems. Although the intraoperative navigation is more commonly used in thoracolumbar spine surgery, this newer imaging platform has rapidly gained popularity in cervical approaches. The purpose of this manuscript is to address the applications of advanced image-guidance in cervical spine surgery and to describe the use of intraoperative neuro-navigation in surgical planning and execution. In this review, we aim to cover the following surgical techniques: anterior cervical approaches, atlanto-axial fixation, subaxial instrumentation, percutaneous interfacet cage implantation as well as minimally invasive posterior cervical foraminotomy (PCF) and unilateral laminotomy for bilateral decompression. The currently available data suggested that the use of 3D navigation significantly reduces the screw malposition, operative time, mean blood loss, radiation exposure, and complication rates in comparison to the conventional fluoroscopic-guidance. With the advancements in technology and surgical techniques, 3D navigation has potential to replace conventional fluoroscopy completely.

The Current State of Cervical Endoscopic Spine Surgery: an Updated Literature Review and Technical Considerations

Introduction: Endoscopic spine surgery has become one of the representative minimally invasive spine surgeries (MISS), especially in the lumbar spine. Full-endoscopic procedures using a working channel endoscope for cervical degenerative spine disease have been reported as practical and feasible. This review aimed to summarize the updated techniques of and studies about cervical endoscopic surgery. Areas covered: An extensive search of PubMed was performed for randomized controlled trials (RCTs) or comparative cohort studies on the full-endoscopic cervical procedure. All the 236 articles found were screened and categorized. Only two RCTs and four cohort studies finally met the search criteria. Regarding the surgical techniques, there are four categories according to the approach method: 1) anterior endoscopic cervical discectomy (AECD); 2) anterior endoscopic cervical transcorporeal decompression (AECTcD); 3) posterior endoscopic cervical foraminotomy and discectomy (PECFD); and 4) posterior endoscopic cervical laminotomy (PECL). Expert opinion: Cervical endoscopic surgery provides comparable clinical results with MISS benefits, such as shorter operative time, less bleeding, and earlier recovery time. However, spine surgeons are not yet familiar with most of these techniques; moreover, supportive evidence is minimal. Technical evolution is still ongoing in an effort to make the procedure more practical.

Outcome and negative events in thoracic disc herniation surgery: a Danish registry study

BACKGROUND

Thoracic disc herniation (TDH) is a surgically demanding entity. Various surgical approaches have been developed and advanced in an attempt to achieve sufficient outcomes and reduce consecutive complication rates. Still, controversy exists regarding selecting the best surgical approach. This retrospective study aims to support decision-making regarding surgical approach.

METHODS

We performed a retrospective analysis of 71 patients who underwent thoracic discectomy at Aarhus University Hospital, Denmark, between 1996 and 2015. Patients were divided into two groups depending on whether a lateral approach or a posterior approach was used. Data on demographics, symptomatology, peri- and post-operative events, length of hospitalization and discharge disposition were assembled from medical records.

RESULTS

Lateral and posterior approach had an approximately equal peri-operative event rate (39% versus 36%), whereas the lateral approach was associated with a higher post-operative event rate in-hospital and post-discharge than the posterior approach (50% versus 18%; 45% versus 40%). The overall probability of improvement in clinical outcome regardless approach at follow-up was 77% in the short-term and 80% in the long-term. Odds of clinical improvement at any time point was 29% higher with the lateral approach than with the posterior approach (OR = 1.29, 95% CI: 0.52-3.21, p = .76). Adjusting for time, the odds of clinical improvement at short-term follow-up was twice as high for the lateral than for the posterior approach (OR = 2.16, 95% CI: 0.16-30.11); however, the trend seems to fade away over time (OR = 1.10, 95% CI: 0.07-17.55).

CONCLUSIONS

The probability of improving after TDH surgery is good. However, a clear conclusion regarding the best surgical approach cannot be established; thus, surgeons should consider pros and cons of each approach when allocating a patient to surgery.

Bilateral translaminar osseous-channel assisted percutaneous full-endoscopic ligamentectomy decompression for thoracic myelopathy due to ossification of the ligamentum flavum: a technical note

Introduction

A variety of surgical procedures have been introduced to treat patients with thoracic myelopathy (TM) caused by ossification of the ligamentum flavum (OLF). However, they are accompanied by significant trauma and risk, and their surgical outcomes are not always satisfactory.

Aim

To describe a bilateral translaminar osseous-channel assisted posterior percutaneous full-endoscopic ligamentectomy decompression (p-PELD) technique as a novel minimally invasive procedure for treating patients with TM due to OLF.

Material and methods

A 51-year-old female patient with persistent thoracolumbar back pain and progressive numbness in the bilateral lower extremities for 2 years underwent percutaneous vertebroplasty (PVP) for T11 osteoporotic compression fractures (OCF) in a regional hospital one week prior to hospitalization. TM caused by canal stenosis and dorsal spinal cord compression at T10/11 secondary to OLF and an OCF at T11 were diagnosed based on clinical presentations and radiologic examinations. After bilateral p-PELD for TM was performed at T10/11, the result was confirmed based on postoperative radiographic and clinical results.

Results

The bilateral OLF was completely removed by the p-PELD technique. No complications were encountered, and her symptoms were sufficiently improved after surgery. The VAS score was 6 points preoperatively and decreased to 0 points at the last follow-up (24 months). The modified Japanese Orthopaedic Association (mJOA) score improved from 2 points preoperatively to 10 points at the final follow-up.

Conclusions

As a minimally invasive technique, the bilateral translaminar osseous-channel assisted p-PELD procedure provided precise and sufficient decompression for the treatment of OLF-related TM.

Long-term clinical and radiological follow-up after anterior endoscopic cervical discectomy: a case report

Anterior endoscopic cervical discectomy (AECD) using laser and micro forceps for cervical intervertebral disc herniation has been considered as an effective treatment modality in selected cases. However, several spine surgeons are concerned about the adverse outcomes of discectomy without fusion, such as postoperative instability, disc space narrowing, and segmental kyphosis. We report two cases of AECD that was performed 19 and 21 years ago. First case was a 44-year-old female with C56 cervical soft disc rupture and second case was a 42-year-old male with C67 cervical soft disc rupture. These patients suffered from cervical intervertebral disc herniation and underwent AECD. The surgical method followed the general AECD method that removed selectively-ruptured particle only. In both cases, the symptoms improved after AECD, and these patients did not experience any problems until recently. Good clinical results have been shown over the long-term, as seen in the two cases described here. In the radiological evaluation, it was confirmed that the postoperative level was stable and disc height was preserved. Furthermore, sagittal alignment and segmental motion of the cervical vertebra were both maintained. In these two cases, disc height was insignificantly different before and after surgery over a long period. Thus, AECD provides good results, even in long-term follow-up, without acceleration of disc degeneration.

Posterior Percutaneous Transpedicular Endoscopic Approach for Treating Single-Segment Cervical Myelopathy

Background

Standard posterior percutaneous endoscopic cervical discectomy (PECD) is considered an effective minimally invasive surgery. Although standard PECD can be used to treat radiculopathy with relatively minimal trauma, it is still a challenge to use this approach for treating myelopathy.

Objective

This report is aimed at first describing a posterior transpedicular approach under endoscopy for myelopathy and evaluating the feasibility and short-term clinical effects of this approach.

Methods

In our retrospective analysis between Feb. 2016 to Mar. 2017, 16 patients managed with PECD using the posterior transpedicular approach for symptomatic single-segment myelopathy. Surgery involved drilling 1/2 to 2/3 of the medial portion of the pedicle under endoscopy to provide sufficient space and an appropriate angle for inserting the endoscope into the spinal canal, followed by ventral decompression of the spinal cord. Computed tomography and magnetic resonance imaging were used to evaluate pedicle healing and spinal cord decompression. The primary outcomes included a visual analog scale (VAS) scores of axial neck pain and Japanese Orthopaedic Association (JOA) scores of neurological conditions.

Results

All patients completed a 1-year follow-up examination. The mean duration of surgery was 95.44 ± 19.44 min (52–130 min). The fluoroscopy duration was 5.88 ± 1.05 (4–7). The VAS scores of axial pain significantly improved from 6.94 ± 0.75 preoperatively to 2.88 ± 1.22 postoperatively (P < 0.05). The mean JOA scores improved from 8.50 ± 1.12 preoperatively to 14.50 ± 1.46 at the final follow-up (P < 0.05). The effects were excellent in 8 cases, good in 6 cases, and fair in 2 cases. After partial pedicle excision, the width of the remaining pedicle was 1.70 ± 0.22 mm postoperatively and significantly recovered to 3.38 ± 0.49 mm at the 1-year follow-up. There were no surgery-related complications, such as dural tearing, spinal cord injury, nerve root injury, pedicle fracture, and cervical hematocele or infection.

Conclusions

The posterior transpedicular approach is an effective method for the treatment of myelopathy in select patients and is a supplement to the described surgical approach for PECD.

A comparison of experimental compressive axial loading testing with a numerical simulation of topologically optimized cervical implants made by selective laser melting

In recent years, the number of cervical interventions has increased. The stress shielding effect is a serious complication in cervical spine interventions. Topological optimization is based on finite element method structural analysis and numerical simulations. The generated design of cervical implants is made from Ti6Al4V powder by selective laser melting while the optimized cage is numerically tested for compressive axial loading and the results are compared with experimental measurement. Additive manufacturing technologies and new software possibilities in the field of structural analysis, which use the finite element method tools, help to execute implant topological optimization that is useful for clinical practice. The inner structures of the implant would be impossible to make by conventional manufacturing technologies. The resulting implant design, after modification, must fulfill strict application criteria for the area of cervical spine with respect to its material and biomechanical properties. The aim of this work was to alter the mechanical properties of the cervical intervertebral cage to address the clinical concern of the stress shielding effect by topological optimization. A methodology of cervical implant compressive axial loading numerical simulation was created, and subsequent experimental testing was done to obtain real material properties after a selective laser melting process. The weight of the optimized implant was reduced by 28.92 %. Results of the experimental testing and numerical simulation of topologically optimized design showed 10-times lower stiffness compared to the solid cage design, and the real yield strength of the optimized structure is 843.8 MPa based on experimental results.

Analysis of compliance and efficacy of integrated management of whole process in the choice of percutaneous full-endoscopic surgery for patients with cervical disc herniation

Background

Percutaneous spinal endoscopy is a new type of surgery for the treatment of cervical disc herniation. It can avoid the complications of the classic anterior cervical discectomy and fusion (ACDF) approach and the risk of adjacent spondylosis. How can we effectively improve patients’ awareness of spinal endoscopy and their election of endoscopic techniques?

Objective

To analyze the compliance and clinical effect of the integrated management of the whole process in the choice of percutaneous full-endoscopic surgery for patients with cervical disc herniation.

Methods

Retrospective analysis of 72 patients with cervical disc herniation undergoing surgery in our hospital from August 2015–August 2017 was performed. The whole-process integrated management model was used for all the patients. The 36 patients in the experimental group were treated by percutaneous full-endoscopic cervical discectomy, and the 36 patients in the control group were treated by ACDF. The postoperative feeding time, time to get out of bed, length of hospital stay, compliance, clinical efficacy, and recurrence rate of neck pain were observed. Changes between the preoperative and postoperative pain visual analog scale (VAS) scores and neurological function Japan Orthopaedic Association (JOA) scores were assessed.

Results

The postoperative feeding time in the experimental group was 8.319 ± 1.374 h, the postoperative time to get out of bed was 16.64 ± 3.728 h, and the hospitalization time was 6.403 ± 0.735 days. The excellent and good clinical efficacy rate was 91.67%, the compliance rate was 88.89%, and the neck pain recurrence rate was 5.56%. The postoperative feeding time in the control group was 26.56 ± 9.512 h, the postoperative time to get out of bed was 45.06 ± 9.027 h, and the length of hospital stay was 8.208 ± 0.865 days. The excellent and good clinical efficacy rate was 88.89%, the compliance rate was 69.4%, and the neck pain recurrence rate was 8.33%. There was no significant difference between the two groups in the excellent efficacy rate and the neck pain recurrence rate, p > 0.05. The compliance rate in the experimental group was better than that in the control group, and the difference was statistically significant, p < 0.05. The hospitalization time of the experimental group was significantly lower than that of the control group, and the difference was statistically significant, p < 0.05. The postoperative VAS scores and JOA scores of the two groups were significantly better than the preoperative scores, and the difference was statistically significant, p < 0.05; there was no significant difference between the two groups, p > 0.05.

Conclusion

The integrated management of the whole course can effectively improve the compliance of patients with cervical disc herniation receiving endoscopic treatment, yield the same treatment effect as the classic operation, shorten the hospitalization time, speed up the turnover of hospital beds, and improve satisfaction with medical quality and is worthy of clinical application.

A Historical Review of Endoscopic Spinal Discectomy

As an essential component of minimally invasive spine surgery, endoscopic spine surgery (ESS) has continuously evolved and has been accepted as a practical procedure by the worldwide spine community. Especially for lumbar disc herniation (LDH), the percutaneous endoscopic or full-endoscopic discectomy technique has been scientifically proven through randomized controlled trials and meta-analyses to be a good alternative to open discectomy. The initial concept of endoscopic spine discectomy was concerned with indirect disc decompression using various instruments such as blind forceps, a nucleotome, laser, radiofrequency coblation, and some chemical agents. The main surgical field has been shifted from the intradiscal space to the epidural space. Precise and selective discectomy for extruded LDH in the epidural space under high-quality endoscopic visualization is now feasible. Furthermore, the medical applications of ESS is broadening to include spinal stenosis, segmental instability, infection, and even intradural lesions. In this review article, I describe the history of endoscopic spine discectomy and decompression techniques, as well as evolution of the paradigm. This history may help indicate the future of practical ESS.

Fibrin sealants in lumbar annuloplasty after endoscopic discectomy as a method to prevent recurrent lumbar disc herniation

Fibrin sealant as a promising agent for providing scaffold and efficient hemostasis is widely accepted in several specialties. However, the outcome of Fibrin sealants in lumbar annuloplasty after endoscopic discectomy has not been evaluated in patients with disc herniation. The goal of this study was to evaluate the efficacy, response, and probability of future recurrence rates in herniated nucleus pulposus (HNP) with the use of fibrin sealant in conjunction with endoscopic disc surgery. A total of 35 patients (28 men, 7women) were evaluated, including 18 patients who underwent endoscopic discectomy alone and 17 patients that received fibrin sealant at the site of annulus tear and endoscopic discectomy. All patients were followed through both clinical and imaging methods for an average of 10.5 months. Primary outcome measure was defined as lumbar decompression approved by imaging and symptom alleviation after endoscopic spinal discectomy with Visual Analogue Scale (VAS) score ≤ 4 (cut-off point). Median size of annular tearing was significantly lower in the endoscopic discectomy group (median, 3) (minimum, 2; maximum, 5); however, the corresponding factor in the endoscopic discectomy plus fibrin sealant group was significantly larger (median, 6) (minimum, 5; maximum, 10), with P <0.001. Only one patient in the endoscopic discectomy group had an HNP recurrence during follow-up compared to two patients in the endoscopic discectomy plus fibrin sealant group. Due to the temporary effects of fibrin sealant in preventing disc herniation and the observed recurrence rate in both the case and control groups, the results of this study suggest a role of fibrin sealants combined with endoscopic discectomy to prevent early HNP recurrence rate.

Outcomes of Discectomy by Using Full-Endoscopic Visualization Technique via the Transcorporeal and Transdiscal Approaches in the Treatment of Cervical Intervertebral Disc Herniation: A Comparative Study

Objective

To compare the difference in clinical and radiographic outcomes between anterior transcorporeal and transdiscal percutaneous endoscopic cervical discectomy (ATc-PECD/ATd-PECD) approaches for treating patients with cervical intervertebral disc herniation (CIVDH).

Method

We selected 77 patients with single-segment CIVDH and received ATc-PECD or ATd-PECD in the Second Affiliated Hospital of Chongqing Medical University between March 1, 2010, and July 1, 2015. 35 patients suffered from ATc-PECD, and there were 42 patients in the ATd-PECD group. Obtaining the data of 1, 3, 6, 12, and 24 months postoperatively, the VAS for neck and arm pain and the modified MacNab criteria were used to evaluate the clinical outcomes, comparing radiographic outcomes and complications of these two groups.

Results

We found that the mean operative time was significantly longer in the ATc-PECD group (P < 0.05). At the 2-year follow-up, the mean VAS score for neck and arm pain was significantly decreased in both two groups. There was no significant difference in the VAS score for arm pain and neck pain between the two groups at the 2-year follow-up (P=0.783 and P=0.785, respectively). For the ATc-PECD group, the difference in the height of IVS or vertebral body was significant between the preoperative and postoperative groups (P < 0.05, respectively). For the ATd-PECD group, there was only a significant decrease in the height of the IVS (P < 0.05); the decrease in the surgical vertebral body was not significant between the preoperative and postoperative groups (P > 0.05).

Conclusion

In the 2-year follow-up, there is no significant difference in the clinical outcomes between the 2 approaches. While the longer time was consumed in the ATc-PECD group, the lower rate of disc collapse and recurrence is notable. Additionally, when the center diameter of tunnel was limited to 6 mm, the bony defect can be healed without the occurrence of the collapse of the superior endplate, and ATc-PECD may be preferable in the endoscopic treatment of CIVDH.

[Clinical study of single-level cervical disc herniation treated by full-endoscopic decompression via anterior transcorporeal approach]

OBJECTIVE

To investigate the clinical feasibility of full-endoscopic decompression for the treatment of single-level cervical disc herniation via anterior transcorporeal approach.

METHODS

According to the inclusion and exclusion criteria, 21 patients with cervical disc herniation who received full-endoscopic decompression via anterior transcorporeal approach between September 2014 and March 2016 were retrospectively analyzed. There were 12 males and 9 females with an age ranged from 32 to 65 years, with an average of 48.5 years. The duration of symptoms ranged from 6 to 18 weeks, with an average of 10.5 weeks. According to the Nurick grading of spinal cord symptoms, there were 2 cases with grade 1, 7 cases with grade 2, and 12 cases with grade 3. Operative segment was C 3, 4 in 2 cases, C 4, 5 in 8 cases, C 5, 6 in 9 cases, and C 6, 7 in 2 cases. The operation time and related complications were recorded. The central vertical height of the vertebral body and the diseased segment space were measured on the cervical X-ray film. The neck and shoulder pain were evaluated by visual analogue scale (VAS) score; Japanese Orthopaedic Association (JOA) score was used to evaluate the improvement of neurological function in patients. The MRI of cervical spine was reexamined at 3 months after operation, and the CT of cervical spine was reexamined at 12 months after operation. The decompression of spinal cord and the healing of bone canal in the vertebral body were further evaluated.

RESULTS

Full-endoscopic decompression via anterior transcorporeal approach were achieved at all 21 patients. The operation time was 85-135 minutes, with an average of 96.5 minutes. All patients were followed up 24-27 months, with an average of 24.5 months. There was no complication such as residual nucleus pulposus, spinal cord injury, large esophageal vessels injury, pleural effusion, endplate collapse, intraspinal hematoma, cervical spine instability, protrusion of disc in the same segment, or kyphosis. Both VAS scores of neck and shoulder pain and JOA scores were significantly improved at 12 months after operation ( P<0.05). At 3 months after operation, it was confirmed by the cervical MRI that neural decompression was sufficient and the abnormal signal was also degraded in the patients with intramedullary high signal at T2-weighted image. The cervical CT showed that bone healing were achieved in the surgical vertebral bodies of all patients at 12 months after operation. At 24 months after operation, the central vertical height of the diseased segment space significantly decreased compared with preoperative one ( t=2.043, P=0.035); but there was no significant difference in the central vertical height of the vertebral body between pre- and post-operation ( t=0.881, P=0.421).

CONCLUSION

Full-endoscopic decompression via anterior transcorporeal approach, integrating the advantages of the endoscopic surgery and the transcorporeal approach, provide an ideal and thorough decompression of the ventral spinal cord with satisfactory clinical and radiographic results.

Percutaneous Endoscopic Thoracic Decompression for Thoracic Spinal Stenosis Under Local Anesthesia

BACKGROUND

Thoracic spinal stenosis (TSS), a common vertebral degenerative disease, is generally treated via surgical decompression. Percutaneous endoscopic thoracic decompression (PETD) under local anesthesia is considered a relatively safe, minimally invasive procedure. Few reports detail the success of endoscopic decompression for treatment of TSS caused by ossification of ligamentum flavum, the most common cause of TSS. This study investigated application of PETD for treatment of TSS caused by ossification of ligamentum flavum, ossification of posterior longitudinal ligament, or thoracic disc herniation.

METHODS

From January 2017 to January 2019, 12 consecutive patients (6 men and 6 women) underwent PETD. TSS was caused by ossification of ligamentum flavum in 5 patients, thoracic disc herniation in 5 patients, and ossification of posterior longitudinal ligament in 2 patients. All cases were followed up for 1 year postoperatively. Preoperative and postoperative neurologic status was evaluated using the modified Japanese Orthopaedic Association score, and complications were documented.

RESULTS

Average modified Japanese Orthopaedic Association score improved significantly from 6.25 ± 1.60 preoperatively to 9.75 ± 1.21 at final follow-up. Dural tear was observed in 1 case during the intervention, and 1 case had transient worsening of preoperative paralysis. Recovery at final follow-up was classified as excellent in 5 cases, good in 6 cases, and poor in 1 case.

CONCLUSIONS

This retrospective analysis showed that PETD under local anesthesia may be a feasible alternative to treat TSS in elderly patients with other underlying complications for whom general anesthesia or major surgical trauma would be harmful.

Minimal Clinically Important Difference in Patient-Reported Outcome Measures with the Transforaminal Endoscopic Decompression for Lateral Recess and Foraminal Stenosis

Background

Patient-reported outcome measures (PROMs) have become widely used to better measure patients' judgment of treatment benefits from surgical spine care. The concept of determining the minimal clinically important differences (MCIDs) of PROMs is aimed at assessing the benefits of lumbar spine care that are meaningful to the patient. The goal of this study was to validate the utility of MCIDs of the visual analog score (VAS) and Oswestry Disability Index (ODI) in patients with sciatica-type low back and leg pain due to lateral recess and foraminal stenosis who were treated with directly visualized transforaminal outpatient endoscopic decompression.

Methods

The retrospective study population consisted of 406 patients on whom PROMs were obtained preoperatively, and again postoperatively at final follow-up. Employing an anchor-based approach with a patient satisfaction index based on the modified Macnab criteria, a receiver operating characteristics (ROC) and area under the curve (AUC) analysis was performed using IBM SPSS 25.0 to define the optimal MCID in VAS and ODI with the transforaminal endoscopy using the top-left-corner criteria and the Youden index. Improvements in walking endurance were recorded as an additional parameter of patient functioning and correlated with PROMs to test for statistical significance.

Results

The patients' average age was 41.08 years, ranging from 30 to 84 years. The mean follow-up was 33.59 months, ranging from 24 to 85 months, with a standard deviation of 12.79. The MCIDs for VAS and ODI were 2.5 to 3.5 and 15 to 16.5, respectively. Patients were dichotomized as improved (377/406; 92.9%) if they reported excellent (224/406; 55.2%), good (112/406; 27.6%), and fair (41/406; 10.1%) Macnab outcomes. Patients were dichotomized as failed if they reported poor (29/406; 7.1%) Macnab outcomes. Preoperatively, only 32.5% (132/406) of patients had unlimited walking endurance compared to 77.6% (315/406) of patients postoperatively. The ROC and AUC analysis showed better accuracy with the single-integer VAS score (0.926) than with the 10-item ODI score (0.751).

Conclusions

Transforaminal outpatient endoscopic decompression for symptomatic foraminal and lateral recess stenosis is an effective surgical treatment to alleviate sciatica-type and back symptoms in 92.9% of patients. Of the PROMs analyzed, the VAS provided a more meaningful and accurate reflection of patients' interpretation of outcome with the transforaminal endoscopic spinal decompression procedure than ODI. Understanding which patient expectations drive these MCIDs may aid in replacing open surgeries for sciatica-type low back and leg pain currently preferred by traditional spine surgeons with a personalized early-staged transforaminal endoscopic hybrid decompressive/ablative procedures favored by the authors. These may prove more cost effective by focusing on significant pain generators validated with a diagnostic interventional workup instead of employing image-based indication criteria for surgery.

AOSpine Consensus Paper on Nomenclature for Working-Channel Endoscopic Spinal Procedures

STUDY DESIGN

International consensus paper on a unified nomenclature for full-endoscopic spine surgery.

OBJECTIVES

Minimally invasive endoscopic spinal procedures have undergone rapid development during the past decade. Evolution of working-channel endoscopes and surgical instruments as well as innovation in surgical techniques have expanded the types of spinal pathology that can be addressed. However, there is in the literature a heterogeneous nomenclature defining approach corridors and procedures, and this lack of common language has hampered communication between endoscopic spine surgeons, patients, hospitals, and insurance providers.

METHODS

The current report summarizes the nomenclature reported for working-channel endoscopic procedures that address cervical, thoracic, and lumbar spinal pathology.

RESULTS

We propose a uniform system that defines the working-channel endoscope (full-endoscopic), approach corridor (anterior, posterior, interlaminar, transforaminal), spinal segment (cervical, thoracic, lumbar), and procedure performed (eg, discectomy, foraminotomy). We suggest the following nomenclature for the most common full-endoscopic procedures: posterior endoscopic cervical foraminotomy (PECF), transforaminal endoscopic thoracic discectomy (TETD), transforaminal endoscopic lumbar discectomy (TELD), transforaminal lumbar foraminotomy (TELF), interlaminar endoscopic lumbar discectomy (IELD), interlaminar endoscopic lateral recess decompression (IE-LRD), and lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD).

CONCLUSIONS

We believe that it is critical to delineate a consensus nomenclature to facilitate uniformity of working-channel endoscopic procedures within academic scholarship. This will hopefully facilitate development, standardization of procedures, teaching, and widespread acceptance of full-endoscopic spinal procedures.

Surgical treatment of cervical radiculopathy using an anterior cervical endoscopic decompression

Background

Anterior endoscopic cervical decompression with discectomy and foraminotomy is an alternative to open surgical treatment of unrelenting cervical radiculopathy (CR) in patients who have failed non-operative treatment. The purpose of the study is to present the clinical outcomes of patient with CR treated with an anterior endoscopic approach.

Methods

We reviewed the medical records of 293 patients diagnosed with CR and treated with an anterior endoscopic cervical decompression between 1997 and 2018. Primary outcome measures were modified Macnab as well as pre- and postoperative visual analog scale (VAS) criteria.

Results

The average surgical time was 65 minutes. At 12 months follow-up, Excellent and Good Macnab outcomes were achieved in 90.1% of patients. The average VAS score reduction was 5.6. Complications occurred in 8 patients and were treated with a second procedure in 10 patients.

Conclusions

The anterior endoscopic cervical decompression is an attractive alternative to open anterior cervical discectomy and fusion (ACDF) with a low complication and reoperations rate.

Fibrin sealants in lumbar annuloplasty after endoscopic discectomy as a method to prevent recurrent lumbar disc herniation

Fibrin sealant as a promising agent for providing scaffold and efficient hemostasis is widely accepted in several specialties. However, the outcome of Fibrin sealants in lumbar annuloplasty after endoscopic discectomy has not been evaluated in patients with disc herniation. The goal of this study was to evaluate the efficacy, response, and probability of future recurrence rates in herniated nucleus pulposus (HNP) with the use of fibrin sealant in conjunction with endoscopic disc surgery. A total of 35 patients (28 men, 7women) were evaluated, including 18 patients who underwent endoscopic discectomy alone and 17 patients that received fibrin sealant at the site of annulus tear and endoscopic discectomy. All patients were followed through both clinical and imaging methods for an average of 10.5 months. Primary outcome measure was defined as lumbar decompression approved by imaging and symptom alleviation after endoscopic spinal discectomy with Visual Analogue Scale (VAS) score ≤ 4 (cut-off point). Median size of annular tearing was significantly lower in the endoscopic discectomy group (median, 3) (minimum, 2; maximum, 5); however, the corresponding factor in the endoscopic discectomy plus fibrin sealant group was significantly larger (median, 6) (minimum, 5; maximum, 10), with P <0.001. Only one patient in the endoscopic discectomy group had an HNP recurrence during follow-up compared to two patients in the endoscopic discectomy plus fibrin sealant group. Due to the temporary effects of fibrin sealant in preventing disc herniation and the observed recurrence rate in both the case and control groups, the results of this study suggest a role of fibrin sealants combined with endoscopic discectomy to prevent early HNP recurrence rate.

Use of an Internal Retractor for Percutaneous Full-Endoscopic Resection in Cervical Intervertebral Disc Herniation with a Posterior Approach

Study Design

A preliminary case series study.

Purpose

For the safety of performing a posterior percutaneous full-endoscopic cervical discectomy.

Overview of Literature

Because of the lack of space for inserting an outer sheath above the intervertebral disc in the spinal canal, grasping the herniated disc with forceps while retracting the nerves with the forceps itself was required. This procedure produces the risk of inadvertently injuring nerves because of inadequate visualization of the hernia and inadequate protection of the nerve.

Methods

Our new internal retractor can be inserted into the working channel of a percutaneous full-endoscope, enabling the insertion of a second tool. After partial foraminotomy, the internal retractor and forceps were manipulated to reliably retract the nerve root. Finally, the herniated disc was resected under an endoscopic view.

Results

All six cases had a good postoperative course, and postoperative neuropathy was not observed.

Conclusions

This internal retractor allows for the secure resection herniated cervical intervertebral discs.

Percutaneous Endoscopic Cervical Discectomy Versus Anterior Cervical Discectomy and Fusion: A Comparative Cohort Study with a Five-Year Follow-Up

Percutaneous endoscopic cervical discectomy (PECD) is an effective minimally invasive surgery for soft cervical disc herniation in properly selected cases. The current gold standard is anterior cervical discectomy and fusion (ACDF). However, few studies have evaluated the outcome of PECD compared with ACDF. We compared the surgical results of PECD and ACDF. Data from patients treated with single-level PECD (n = 51) or ACDF (n = 64) were analyzed. Patients were prospectively entered into the clinical database and their records were retrospectively reviewed. Perioperative data and clinical outcomes were evaluated using the visual analogue scale (VAS), Neck Disability Index (NDI), and modified Macnab criteria. VAS and NDI results significantly improved in both groups. The rates of excellent or good results were 88.24% and 90.63% in the PECD and ACDF group, respectively. The revision rates were 3.92% and 1.56% in the PECD and ACDF group, respectively. Operative time, hospital stay, and time to return to work were reduced in the PECD group compared to the ACDF group (p < 0.001). The five-year outcomes of PECD were comparable to those of conventional ACDF. PECD provided the typical benefits of minimally invasive surgery and may be an effective alternative for treating soft cervical disc herniation.