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

A narrative review of endoscopic spine surgery: history, indications, uses, and future directions

Background and Objective

The concept of endoscopic surgery began in the 1930s and has since undergone numerous advancements in both technology and surgical indications. Its main benefit is providing the opportunity to perform surgery while minimizing disruption to surrounding structures. The purpose of this review is to summarize the history, uses, and future directions for spine endoscopic surgery.

Methods

A review of national databases was performing using key terms "endoscopic", "spine" and "surgery" for literature from 1900 to 2023. Studies that aimed to describe the utilities of endoscopic surgeries, associated outcomes, limitations, and future directions were included. Studies that were not in English were excluded.

Key Content and Findings

This review includes a brief overview of the history of endoscopic surgery and its current two main approaches, transforaminal and interlaminar approaches. It then summarizes the main indications and utilization of endoscopic surgery in the lumbar, cervical and thoracic spine, as well as expansion in managing spine tumors, infections, and outpatient surgical cases.

Conclusions

There are many rising indications and uses for endoscopic spine surgery in nearly every aspect of the spine. Compared to conventional spine surgery, there is early evidence showing endoscopic surgery is associated with less post-operative pain, shorter hospital stays, and possibly quicker recovery times. As current trends in spine surgery move towards minimally invasive techniques, it is anticipated that the use of endoscopic surgery will continue to expand.

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.

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.

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.

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.

Advances and Challenges of Endoscopic Spine Surgery

The purpose of this paper is to review the data supporting current endoscopic surgical techniques for the spine and the potential challenges and future of the field. The origins of endoscopic spine surgery can be traced back many decades, with many important innovations throughout its development. It can be applied to all levels of the spine, with many robust trials supporting its clinical outcomes. Continued clinical research is needed to explore its expanding indications. Although the limitations of starting an endoscopic program can be justified by its cost effectiveness and positive societal impact, challenges facing its widespread adoption are still present. As more residency and fellowship programs include endoscopy as part of their spine training, it will become more prevalent in hospitals in the United States. Technological advancements in spine surgery will further propel and enhance endoscopic techniques as they become an integral part of a spine surgeon's repertoire.

Channel-assisted cervical key hole technology combined with ultrasonic bone osteotome versus posterior percutaneous endoscopic cervical foraminotomy: a clinical retrospective study

PURPOSE

The search for more effective and safe treatment methods for cervical spondylotic radiculopathy (CSR) has led to the rapid development and increasing popularity of minimally invasive posterior cervical foraminotomy (MI-PCF). This study aims to compare two important approaches for MI-PCF surgery: the channel-assisted cervical key hole technology combined with ultrasonic bone osteotome (CKH-UBO) and posterior percutaneous endoscopic cervical foraminotomy (PPECF).

METHODS

Data from patients treated with single-level CKH-UBO (n = 35) or PPECF (n = 40) were analyzed. Clinical outcomes, including visual analogue scale (VAS) scores for neck and arm pain, Neck Disability Index (NDI), and modified Macnab criteria, were assessed preoperatively, as well as at three days, three months, and one year postoperatively.

RESULTS

The percentages of patients with excellent and good outcomes were 97.14% and 92.5%, respectively. The average surgical time in the CKH-UBO group was significantly shorter than in the PPECF group (p < 0.001), while the average incision length in the PPECF group was significantly smaller than in the CKH-UBO group. There were no significant differences between the two groups in terms of blood loss, hospital stay, and clinical outcomes at three days, three months, and 12 months postoperatively.

CONCLUSION

CKH-UBO can achieve the same surgical outcomes as PPECF for the treatment of CSR. However, CKH-UBO saves more time but requires patients to undergo larger incisions.

Surgical Technique of Central and Over-the-Top Full-Endoscopic Decompression of the Cervical Spine: A Technical Note

Endoscopic surgery of the cervical spine is constantly evolving and the spectrum of its indications has expanded in recent decades. Full-endoscopic techniques have standardized the procedures for posterior and anterior access. The full-endoscopic approach was developed to treat degenerative diseases with the least possible invasion and without causing instability of the cervical spine. The posterior full-endoscopic approach is indicated for the treatment of diseases of the lateral part of the vertebral segment, such as herniations and stenoses of the lateral recess and vertebral foramen. There has been little discussion of this approach to the treatment of central stenosis of the cervical spine. This technical note describes a step-by-step surgical technique for central and over-the-top full-endoscopic decompression in the cervical spine, using a 3.7 mm working channel endoscope. This technique has already been shown to be effective in a recent case series with a 4.7 mm working channel endoscope, and may represent a new treatment option for central or bilateral lateral recess stenosis. There is also the possibility of a bilateral full-endoscopic approach, but this may be associated with greater muscle damage and a longer operative time. Case series and comparative studies should be encouraged to confirm the safety and utility of this technique.

Clinical efficacy of posterior endoscopic cervical modified trench technique in the treatment of cervical spondylotic myelopathy: A retrospective study

To investigate the clinical efficacy of the posterior endoscopic cervical modified trench technique in the treatment of cervical spondylotic myelopathy (CSM). This retrospective study included 9 patients with single-segment CSM, who were treated with posterior endoscopic cervical modified trench technique. Related clinical data, the visual analog scale, Japanese Orthopedic Association (JOA) ratings, JOA improvement rate, the minimum sagittal diameter of the spinal canal, and surgical complications were recorded. There were 5 men and 4 females, with an average age of 60.44 ± 16.49 years. Without any significant side effects like paralysis, vascular damage, or cerebrospinal fluid leaking, all surgeries were successfully completed. One year's worth of follow-up with patients lasted for 8.56 ± 3.68 months. When compared to before surgery, the postoperative visual analog scale ratings, JOA scores, and minimum sagittal diameter of the spinal canal value all showed a substantial improvement (P < .01). At the most recent follow-up, 2 patients had a JOA improvement rate of >75%, 6 patients had a JOA improvement rate of 74 to 50%, 1 patient had a JOA improvement rate of 49 to 25%, and none had a JOA improvement rate of <25%. The JOA improvement rate was above 90% for overall excellent and good ratings. In our study, the ventral epidural space may be maneuvered more easily and instrument-induced nerve discomfort is decreased when using the posterior endoscopic cervical modified trench approach with posterior endoscopy. The short-term clinical effect of the posterior endoscopic cervical modified trench technique for CSM is satisfactory.

The Role and Future of Endoscopic Spine Surgery: A Narrative Review

Many types of surgeries are changing from conventional to minimally invasive techniques. Techniques in spine surgery have also changed, with endoscopic spine surgery (ESS) becoming a major surgical technique. Although ESS has advantages such as less soft tissue dissection and normal structure damage, reduced blood loss, less epidural scarring, reduced hospital stay, and earlier functional recovery, it is not possible to replace all spine surgery techniques with ESS. ESS was first used for discectomy in the lumbar spine, but the range of ESS has expanded to cover the entire spine, including the cervical and thoracic spine. With improvements in ESS instruments (optics, endoscope, endoscopic drill and shaver, irrigation pump, and multiportal endoscopic), limitations of ESS have gradually decreased, and it is possible to apply ESS to more spine pathologies. ESS currently incorporates new technologies, such as navigation, augmented and virtual reality, robotics, and 3-dimentional and ultraresolution visualization, to innovate and improve outcomes. In this article, we review the history and current status of ESS, and discuss future goals and possibilities for ESS through comparisons with conventional surgical techniques.

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.

Microscopic Anterior Cervical Discectomy and Fusion Versus Posterior Percutaneous Endoscopic Cervical Keyhole Foraminotomy for Single-level Unilateral Cervical Radiculopathy: A Systematic Review and Meta-analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The objective of this study was to compare the safety of microscopic anterior cervical discectomy and fusion (MI-ACDF) and posterior percutaneous endoscopic keyhole foraminotomy (PPEKF) in patients diagnosed with single-level unilateral cervical radiculopathy.

SUMMARY OF BACKGROUND DATA

After conservative treatment, the symptoms will be relieved in about 90% of cervical radiculopathy patients. For the other one tenth of patients, surgical treatment is needed. The overall complication rate of MI-ACDF and PPEKF ranges from 0% to 25%, and the reoperation rate ranges from 0% to 20%.

MATERIALS AND METHODS

Electronic retrieval of studies from PubMed, Embase, and Cochrane Library was performed to identify comparative or single-arm studies on MI-ACDF and PPEKF. A total of 24 studies were included in our meta-analysis by screening according to the inclusion and exclusion criteria. After data extraction and quality assessment of the included studies, a meta-analysis was performed by using the R software. The pooled incidences of efficient rate, total complication rate, and reoperation rate were calculated.

RESULTS

A total of 24 studies with 1345 patients (MI-ACDF: 644, PPEKF: 701) were identified. There was no significantly statistical difference in pooled patient effective rate (MI-ACDF: 94.3% vs. PPEKF: 93.3%, P =0.625), total complication rate (MI-ACDF: 7.1% vs. PPEKF: 4.7%, P =0.198), and reoperation rate (MI-ACDF: 1.8% vs. PPEKF: 1.1%, P =0.312). However, the common complications of the 2 procedures were different. The most common complications of MI-ACDF were dysphagia and vertebral body sinking, whereas the most common complication of PPEKF was nerve root palsy.

CONCLUSIONS

Both MI-ACDF and PPEKF can provide a relatively safe and reliable treatment for single-level unilateral cervical radiculopathy. The 2 techniques are not significantly different in terms of effective rate, total complication rate, and reoperation rate.

Global Trends and Hotspots in Endoscopic Discectomy: A Study Based on Bibliometric Analysis

OBJECTIVE

With the advancement of minimally invasive spine surgery, endoscopic discectomy (ED) has become a common technique for degenerative disease of the spine. The present study aimed to explore the knowledge structure, emerging trends, and future research hotspots in this field.

METHODS

All relevant publications on ED from 2002 to 2021 were extracted from the Web of Science databases. Key bibliometric indicators, including countries/regions, institutions, authors, journals, references, and keywords were calculated and evaluated using VOSviewer and CiteSpace software.

RESULTS

A total of 1,196 articles and reviews were included for analysis. The number of publications regarding ED increased yearly. From the quality and quantity viewpoint, China, South Korea, and the United States were the major contributors in this field. The most influential institution in the field of ED was Wooridul Spine Hospital. We identified 3,488 authors, among which Lee SH had the most significant number of papers, and Ruetten S was cocited most often. <World Neurosurgery was the journal with the most papers, and Spine was the most commonly cocited journal. Keywords were stratified into 4 clusters by VOSviewer software: cluster 1 (clinical outcomes of ED in the treatment of lumbar disc herniation); cluster 2 (surgical technique of percutaneous endoscopic lumbar discectomy); cluster 3 (clinical outcomes of ED in the treatment of lumbar spinal stenosis); and cluster 4 (clinical outcomes of percutaneous endoscopic cervical discectomy). Several topics including lateral recess stenosis, spinal stenosis, and reoperation were considered as the next hotspot in ED research.

CONCLUSION

ED research has gained considerable attention over the last 2 decades. Our bibliometric findings illuminate the publication trends and research hotspots of the ED field, which may provide useful references for scholars and decision-makers interested in this field.

Efficacy and safety of percutaneous endoscopic cervical discectomy for cervical disc herniation: a systematic review and meta-analysis

BACKGROUND

Since there are currently no systematic evidence-based medical data on the efficacy and safety of PECD, this meta-analysis pooled data from studies that reported the efficacy or safety of PECD for cervical disc herniation to examine the efficacy, recurrence and safety of using PECD to treat cervical disc herniation.

METHODS

We searched the PubMed, EMBASE and Cochrane Library databases for studies published from inception to July 2022. Nine nonrandomized controlled trials (non-RCTs) that reported the efficacy or safety of percutaneous endoscopic cervical discectomy for cervical disc herniation were included. We excluded duplicate publications, studies without full text, studies with incomplete information, studies that did not enable us to conduct data extraction, animal experiments and reviews. STATA 15.1 software was used to analyse the data.

RESULTS

The proportions of excellent and good treatment results after PECD for CDH were 39% (95% CI: 31-48%) and 47% (95% CI: 34-59%), respectively. The pooled results showed that the VAS scores at 1 week post-operatively (SMD = -2.55, 95% CI: - 3.25 to - 1.85) and at the last follow-up (SMD = - 4.30, 95% CI: - 5.61 to - 3.00) after PECD for cervical disc herniation were significantly lower than the pre-operative scores. The recurrence rate of neck pain and the incidence of adverse events after PECD for cervical disc herniation were 3% (95% CI: 1-6%) and 5% (95% CI: 2-9%), respectively. Additionally, pooled results show that the operative time (SMD = - 3.22, 95% CI: - 5.21 to - 1.43) and hospital stay (SMD = - 1.75, 95% CI: - 2.67to - 0.84) were all significantly lower for PECD than for ACDF. The pooled results also showed that the proportion of excellent treatment results was significantly higher for PECD than for ACDF (OR = 2.29, 95% CI: 1.06-4.96).

CONCLUSION

PECD has a high success rate in the treatment of CHD and can relieve neck pain, and the recurrence rate and the incidence of adverse events are low. In addition, compared with ACDF, PECD has a higher rate of excellent outcomes and a lower operative time and hospital stay. PECD may be a better option for treating CHD.

Clinical effect of channel assisted cervical key hole technology combined with ultrasonic bone osteotome in the treatment of single segment cervical spondylotic radiculopathy

OBJECTIVE

To explore the clinical effect and operating skills of channel assisted Cervical Key Hole technology combined with Ultrasonic Bone Osteotome (CKH-UBO) in the treatment of single segment cervical spondylotic radiculopathy (CSR).

METHODS

From June 2018 to June 2020, 14 patients diagnosed with CSR and treated with channel assisted CKH-UBO were collected. The duration of the disease, the length of the incision, the operation time, the amount of bleeding during the operation, the length of hospitalization and the complications were recorded. The Range Of Motion (ROM) and the stability of the surgical segment were recorded before and after the operation. Visual analog scale (VAS), neck disability index (NDI) and modified macnab efficacy evaluation criteria were used to evaluate the surgical efficacy.

RESULTS

The operative segments of the enrolled patients were all lower cervical vertebrae. The average incision length was 2.0 ± 0.1 cm, the operation time was 42.2 ± 5.7 min, the intraoperative bleeding volume was 32.7 ± 4.1 ml, and the hospital stay was 5.6 ± 1.2 days. There was no difference in ROM between preoperative and 3 months and 1 year after operation (P > 0.05), and all patients did not have segmental instability. The VAS scores of neck pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 5.6 ± 1.2, 1.6 ± 0.6, 1.1 ± 0.7, 0.6 ± 0.5, and the VAS scores of upper limb pain were 6.2 ± 1.2, 1.7 ± 0.7, 1.1 ± 0.6, 0.6 ± 0.5. The NDI scores of upper limb pain before surgery, 3 days after surgery, 3 months after surgery, and 1 year after surgery were 36.7 ± 3.5, 9.8 ± 2.4, and 3.9 ± 1.5, 1.8 ± 1.0, The VAS and NDI scores at all follow-up time points after operation were significantly lower than those before operation (P < 0.001). One year after operation, the curative effect was evaluated according to the modified macnab evaluation standard, and the excellent and good rate was 100%. The complication rate was 6.25%.

CONCLUSION

Channel assisted CKH-UBO for single segment CSR has the advantages of short operation time, reliable clinical effect, high safety and low complication rate, which is worthy of clinical promotion.

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.

A Review of Endoscopic Spine Surgery: Decompression for Radiculopathy

PURPOSE OF REVIEW

With this manuscript the authors sought to write a succinct review of the origins, as well as the latest advancements in endoscopic spine surgery to serve as a reference frame for physicians looking to learn this approach.

RECENT FINDINGS

At its infancy, the indications for posterolateral and transforaminal endoscopic decompression remained narrow, which prevented the procedure from gaining rapid traction during those days. However, more recently the tides have turned and an increasing number of surgeons are starting to adopt this technique given all its advantages. With the advent of higher quality camera systems and instruments, indications to use a minimally invasive option have gotten significantly broader. The most basic indication for the use of this technology is a soft disc herniation causing compromise of a neural structure that has failed to be managed successfully with non-surgical therapies. The use of endoscopic techniques provides significant advantages to patient outcomes and patient recovery. Endoscopic procedures should not be used as a blanket approach to nerve root decompression, as they certainly have limitations. Most contraindications to this procedure are relative and serve mostly as points to consider when selecting the methods to address neural compression. As these techniques become more widely accepted, we expect its reach and indications to continue to broaden and diversify. The full integration of navigation technologies will likely leapfrog this procedure into the mainstream use.

Patient selection criteria for percutaneous anterior cervical laser versus endoscopic discectomy

BACKGROUND

Percutaneous anterior laser and anterior endoscopic cervical spine surgery are associated with less approach trauma than conventional open cervical spine surgery. The literature illustrating their appropriate use corroborated with objective outcome evidence is scarce. The authors were interested in comparing the clinical outcomes following percutaneous laser disc decompression (PLDD) versus percutaneous endoscopic disc decompression (PEDD). © 2021 Wiley Periodicals LLC.

MATERIALS AND METHODS

Thirty patients with soft contained symptomatic cervical disc herniations and an average age of 50.5 years (range 26 - 68 years; 16 males and 14 females) were prospectively enrolled in 2 groups of 15 patients to be either treated with PLDD or PEDD. All patients underwent PLDD or PEDD under local anesthesia and sedation. Clinical outcomes were assessed with the Macnab criteria VAS score for arm pain. Complications and reoperations were recorded.

RESULTS

There were significant reductions in the VAS score for arm pain from preoperative 8.4 ± 2.5 to 3.1 ± 1.2 in the PLDD group (P < 0.03), and from preoperative 8.6 ± 2.7 to 2.4 ± 1.1 (P < 0.01) in the PEDD group. In the PLDD group, Macnab outcomes were excellent in 21% of patients, good in 44%, fair in 21%, and poor in 14%. In the PEDD group, Macnab outcomes were excellent in 14% of patients, good in 32%, fair in 12%, and poor in the remaining 12%. There were no statistically significant differences in clinical outcomes between the PLDD and the PEDD group. There were no approach-related or surgical complications.

CONCLUSIONS

Tissue trauma is significantly reduced with laser and endoscopic surgery techniques. PLDD and PEDD are both suitable for the specific indication of soft, symptomatic contained cervical disc herniations. The authors' small prospective cohort study indicates that PLDD and PEDD are options for cervical decompression surgery when medical comorbidities or preferences by patients and surgeons dictate more minimally invasive strategies.

Spinal endoscopy: evidence, techniques, global trends, and future projections

The utilization of indirect visualization during procedures has been increasingly replacing traditional forms of direct visualization across many different surgical specialties. The adoption of arthroscopy, using small cameras placed inside joints, has transformed musculoskeletal care over the last several decades, allowing surgeons to provide the same anatomic solutions with less tissue dissection, resulting in lower requirements for inpatient care, reduced costs, and expedited recovery.  For a variety of reasons, spine surgery has lagged behind other specialties in the adoption of indirect visualization.  Nonetheless, patient demand for less invasive spine procedures and surgeon drive to provide these solutions and improve care quality has driven global adoption of spinal endoscopy.  There are numerous endoscopic platforms and techniques currently utilized, and these systems are rapidly evolving.  Additionally, the variance in technology and health system incentives across the globe has generated tremendous regional heterogeneity in the utilization of spinal endoscopic procedures.  We present a consolidated review, including the background, evidence, techniques, and trends in spinal endoscopy, so that clinicians can gain a deeper understanding of this rapidly evolving domain of spinal healthcare.

Morphology of Herniated Disc as a Predictor for Outcomes of Posterior Percutaneous Full-endoscopic Cervical Discectomy in Treating Cervical Spondylotic Radiculopathy

Objective

To quantitively characterize the morphology of cervical disc herniation (CDH) causing cervical spondylotic radiculopathy (CSR) and investigate whether the morphological features of CDH are associated with clinical outcomes in CSR patients treated by posterior percutaneous full‐endoscopic cervical discectomy (PPECD).

Methods

This is a single‐center retrospective study. Eighty‐seven PPECD‐treated patients meeting the inclusion criteria were included between May 2017 and May 2019. Based on preoperative T2‐weighted magnetic resonance imaging (MRI), we designed and measured six morphological parameters of CDH for all patients to reflect its relative position to cervical spinal cord and protruding degree: DC‐SC distance from the center of disc (DC) and the center of spinal cord (SC); DC‐DP distance from the center of cervical disc (DC) to the peak of herniation (DP); internal diameter of the disc; axial length of CDH; central angle of CDH formed by central axes of CDH and spinal cord; the modified index of CDH. We recorded general information, neck disability index (NDI) scores, visual analog scale (VAS) scores of neck and arm of all patients preoperatively and postoperatively at 1‐year follow‐up. The association of preoperative general variables and morphological parameters with clinical outcomes were explored by utilizing logistic regression and receiver operating characteristic curve (ROC) analysis.

Results

The preoperative neck‐VAS, arm‐VAS, and NDI were significantly decreased after PPECD and remained at a low value at follow‐up. In regards to the morphological parameters of CDH, the mean value of DC‐SC distance, DC‐DP distance, internal diameter of the disc, axial length of CDH, central angle of CDH, and modified index of CDH were 1.61 ± 0.30 cm, 1.66 ± 0.32cm, 1.04 ± 0.21 cm, 0.63 ± 0.19cm, 39.38° ± 11.94°, and 0.39 ± 0.24, respectively. For patients grouped by difference in the recovery rate of NDI and arm‐VAS (excellent improved group, EI; and limited improved group, LI), there were no differences in the age, gender, surgical segments, and morphological parameters, except for the central angle of CDH. According to binary logistic regression analysis, only the preoperative central angle of CDH was significantly associated with postoperative NDI recovery (odds ratio: 0.873; 95% confidence interval: 0.819–0.931, P = 0.002). ROC analysis showed the optimal cut‐off value of the central angle of CDH for predicting the postoperative improvement of functional outcomes is 33.788°.

Conclusion

Preoperative morphology of CDH is related to the outcomes of CSR patients after PPECD. Patients with a large central angle of CDH (>33.788°) have more likelihood of ameliorating neurological symptoms of CSR. There is the potential to select the central angle of CDH as a predictor for outcomes of PPECD in treating CSR.

Fully endoscopic cervical spine surgery: What does the future hold?

Fully endoscopic cervical spine surgery is an emerging novel approach to address cervical spinal pathology. Techniques, both anterior and posterior have been adapted to address various cervical pathologies. The primary goal of these procedures like other open techniques is to surgically decompress the canal centrally and/or along the foramen. The narrative review aims to provide the reader an overview of the rapidly advancing field of endoscopic cervical spinal surgery and evaluate whether these newer approaches could potentially reduce the cost and the risk associated with instrumented cervical fusion.

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.

[Percutaneous endoscopic Key-Hole technology for treatment of paracentral cervical disc herniation]

OBJECTIVE

To investigate the effectiveness of percutaneous endoscopic posterior cervical Key-Hole fenestration decompression and nucleus pulposus extirpation in the treatment of paracentral cervical disc herniation.

METHODS

Between December 2015 and October 2018, 29 cases of paracentral cervical disc herniation were treated with percutaneous endoscopic posterior cervical Key-Hole fenestration decompression and nucleus pulposus extirpation. There were 16 males and 13 females, with an average age of 49.7 years (range, 39-78 years). The disease duration was 3.5-15.0 months (mean, 6.2 months). The herniated disc located at C 3, 4 in 2 cases, C 4, 5 in 5 cases, C 5, 6 in 9 cases, C 6, 7 in 12 cases, and C 7, T 1 in 1 case. The main symptoms were radiculopathy symptom. The operation time, intraoperative blood loss, hospital stay, and complications were observed and recorded. Visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, cervical range of motion (ROM), Macnab standard, and cervical segment stability were used to evaluate the efficacy and safety of the operation.

RESULTS

All patients were followed up 11-43 months, with an average of 19.4 months. The operation time was 67-89 minutes (mean, 73.3 minutes); the intraoperative blood loss was 18-30 mL (mean, 22.9 mL); the hospital stay was 5-10 days (mean, 7.3 days). All the incisions healed by first intention. There was 1 case of hypodynia and hyperalgesia in the affected limb after operation,1 case of decreased limb muscle strength. The VAS scores and JOA scores at each time point after operation were superior to those before operation ( P<0.05). There was no significant difference between the time points after operation ( P>0.05). At last follow-up, the effectiveness was rated according to the Macnab standard as excellent in 11 cases, good in 15 cases, fair in 2 cases, and bad in 1 case, with an excellent and good rate of 89.7%. The CT and MRI showed the decompression of spinal canal and nerve canal. There was no significant difference in cervical ROM between pre- and post-operation ( t=1.427, P=0.165), and no surgical segment instability occurred by X-ray films of flexion and extension of cervical vertebrae.

CONCLUSION

For the paracentral cervical disc herniation with simultaneous compression of nerve roots and spinal cord, percutaneous endoscopic posterior cervical Key-Hole fenestration decompression and nucleus pulposus extirpation has the advantages of small trauma, quick recovery, and satisfactory effectiveness, and can be used as a safe and effective minimally invasive procedure.

Enhanced recovery after surgery (ERAS) pathway for microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion

OBJECTIVES

Enhanced recovery after surgery (ERAS) principle and minimally invasive surgery allow patients to recover faster and better postoperatively. Due to a paucity of their integration, this retrospective study aims to assess clinical outcomes of ERAS pathway in microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

PATIENTS AND METHODS

A total of 72 consecutive cases were enrolled. According to their inclusion order, the former 21 cases received microendoscopy-assisted MIS-TLIF without any ERAS approach (control group), while the latter 51 participants underwent the same surgery with ERAS protocol (observation group). Perioperative parameters, including operative duration, intraoperative estimated blood loss (EBL), length of stay, postoperative analgesic usage and ambulatory time, were recorded. Visual analogue scale (VAS, back and leg), Barthel index were obtained before and at three days, one month, six months postoperatively. Modified MacNab criteria and Bridwell grading were used to assess surgical outcome and interbody fusion at one week and two years after surgery, respectively.

RESULTS

Observation group had statistically improved perioperative parameters (operative duration, intraoperative EBL, length of stay, postoperative analgesic usage and ambulatory time) in comparison with control group. Remarkable decreases in VAS (back and leg) were observed continuously at three days, one month and six months post-surgery in both groups when compared with scores prior to the surgery. More significant improvement of VAS (back and leg) was found in observation group at both three days and one month postoperatively. Regarding Barthel index, despite its transient decrease at three days after surgery in control group, it showed statistical increase at postoperative one month when compared with preoperative values in both groups; moreover, its inter-groups comparison revealed much more improvement in patients receiving ERAS recommendations; while at final follow-up, it continued further increase in either group. Marginally higher proportion of patients in observation group showed perfect or good clinical outcome, as well as solid interbody fusion.

CONCLUSIONS

ERAS pathway in microendoscopy-assisted MIS-TLIF has advantages of decreased operative time, reduced intraoperative haemorrhage, increased initial back pain relief, decreased length of stay, lowered analgesic usage and earlier daily activity recovery and thus, benefit postoperative rehabilitation further.