Full-endoscopic cervical posterior foraminotomy for the operation of lateral disc herniations using 5.9-mm endoscopes: a prospective, randomized, controlled study

The evolution and integration of technology in spinal neurosurgery: A scoping review

Spinal disorders pose a significant global health challenge, affecting nearly 5% of the population and incurring substantial socioeconomic costs. Over time, spinal neurosurgery has evolved from basic 19th-century techniques to today's minimally invasive procedures. The recent integration of technologies such as robotic assistance and advanced imaging has not only improved precision but also reshaped treatment paradigms. This review explores key innovations in imaging, biomaterials, and emerging fields such as AI, examining how they address long-standing challenges in spinal care, including enhancing surgical accuracy and promoting tissue regeneration. Are we at the threshold of a new era in healthcare technology, or are these innovations merely enhancements that may not fundamentally advance clinical care? We aim to answer this question by offering a concise introduction to each technology and discussing in depth its status and challenges, providing readers with a clearer understanding of its actual potential to revolutionize surgical practices.

Endoscopic Posterior Cervical Craniolateral Inclinatory Foraminotomy: A Novel Approach for Lamina Preservation During Tandem Decompression of Cervical Spondylotic Radiculopathy Via Unilateral Biportal Endoscopic Spinal Surgery

STUDY DESIGN

Case series.

OBJECTIVE

Endoscopic posterior cervical foraminotomy gains attention for cervical radiculopathy due to its feasibility, better outcomes, and lower complications than traditional approaches, enabling efficient multilevel decompression in a single operation while avoiding anterior cervical diskectomy and fusion-related issues. However, with multilevel decompression, the remnant lamina becomes thin and fragile. We propose craniolateral inclinatory foraminotomy to minimize bone removal during laminotomy, reducing the risk of iatrogenic or postoperative lamina fractures in tandem decompression.

MATERIALS AND METHODS

From 2021 to 2022, 8 consecutive patients underwent the procedure and were followed up for at least 6 months. The VAS, NDI, and MacNab scores were recorded for clinical recovery and patient satisfaction evaluations. Preoperative and postoperative CT scans were utilized to measure the lamina preservation percentage at each level.

RESULTS

The clinical outcomes improved significantly in every patient. No postoperative neck pain, segmental instability, or lamina fracture were observed. The mean lamina preservation percentages of C5, C6, C7, and all vertebrae were 68.8%, 73.22%, 71.86%, and 72.18%, respectively.

CONCLUSIONS

Ongoing technical adjustments will accompany endoscopic technique development to decrease complications and enhance benefits. Our reported technique avoids extensive laminotomy in multilevel tandem decompression, aiming to prevent lamina fractures and anticipate a reduction in postoperative neck pain.

LEVEL OF EVIDENCE

Level IV.

90-Day Emergency Department Utilization and Readmission Rate After Full-Endoscopic Spine Surgery: A Multicenter, Retrospective Analysis of 821 Patients

BACKGROUND AND OBJECTIVES

Emergency department (ED) utilization and readmission rates after spine surgery are common quality of care measures. Limited data exist on the evaluation of quality indicators after full-endoscopic spine surgery (FESS). The objective of this study was to detect rates, causes, and risk factors for unplanned postoperative clinic utilization after FESS.

METHODS

This retrospective multicenter analysis assessed ED utilization and clinic readmission rates after FESS performed between 01/2014 and 04/2023 for degenerative spinal pathologies. Outcome measures were ED utilizations, hospital readmissions, and revision surgeries within 90 days postsurgery.

RESULTS

Our cohort includes 821 patients averaging 59 years of age, who underwent FESS. Most procedures targeted the lumbar or sacral spine (85.75%) while a small fraction involved the cervical spine (10.11%). The most common procedures were lumbar unilateral laminotomies for bilateral decompression (40.56%) and lumbar transforaminal discectomies (25.58%). Within 90 days postsurgery, 8.0% of patients revisited the ED for surgical complications. A total of 2.2% of patients were readmitted to a hospital of which 1.9% required revision surgery. Primary reasons for ED visits and clinic readmissions were postoperative pain exacerbation, transient neurogenic bladder dysfunction, and recurrent disk herniations. Our multivariate regression analysis revealed that female patients had a significantly higher likelihood of using the ED (P = .046; odds ratio: 1.77, 95% CI 1.01-3.1 5.69% vs 10.33%). Factors such as age, American Society of Anesthesiologists class, body mass index, comorbidities, and spanned spinal levels did not significantly predict postoperative ED utilization.

CONCLUSION

This analysis demonstrates the safety of FESS, as evidenced by acceptable rates of ED utilization, clinic readmission, and revision surgery. Future studies are needed to further elucidate the safety profile of FESS in comparison with traditional spinal procedures.

Cervical Spine Stenosis Causing Diaphragmatic Paralysis: A Case Study and Narrative Review of Clinical Presentations and Outcomes

STUDY DESIGN

Case report and narrative review.

OBJECTIVE

To explore the therapeutic role of surgical and nonsurgical treatment of diaphragmatic paralysis secondary to spinal cord and nerve root compression.

SUMMARY OF BACKGROUND DATA

Phrenic nerve dysfunction due to central or neuroforaminal stenosis is a rare yet unappreciated etiology of diaphragmatic paralysis and chronic dyspnea. Surgical spine decompression, diaphragmatic pacing, and intensive physiotherapy are potential treatment options with varying degrees of evidence.

METHODS

The case of a 70-year-old male with progressive dyspnea, reduced hemi-diaphragmatic excursion, and C3-C7 stenosis, who underwent a microscopic foraminotomy is discussed. Literature review (MEDLINE, PubMed, Google Scholar) identified 19 similar reports and discussed alternative treatments and outcomes.

RESULTS AND CONCLUSIONS

Phrenic nerve root decompression and improvement in neuromonitoring signals were observed intraoperatively. The patient's postoperative course was uncomplicated, and after 15 months, he experienced significant symptomatic improvement and minor improvement in hemi-diaphragmatic paralysis and pulmonary function tests. All case reports of patients treated with spinal decompression showed symptomatic and/or functional improvement, while one of the 2 patients treated with physiotherapy showed improvement. More studies are needed to further describe the course and outcomes of these interventions, but early identification and spinal decompression can be an effective treatment.

OCEBM LEVEL OF EVIDENCE

Level-4.

Minimally invasive posterior cervical foraminotomy versus anterior cervical fusion and arthroplasty: Systematic review and updated meta-analysis

Introduction

This study is a systematic review and meta-analysis that investigates the efficacy of different surgical methods for treating cervical disc herniation or cervical foraminal stenosis.

Research question

The research aimed to compare the efficacy of Minimally Invasive Posterior Cervical Foraminotomy (MI-PCF) with anterior approaches, namely Anterior Cervical Discectomy and Fusion (ACDF) and Cervical Disc Arthroplasty (CDA).

Material and methods

The study included a comprehensive review of eight articles that compared ACDF and MI-PCF, and four articles that compared CDA to MI-PCF.

Results

The results indicated no significant difference in surgical duration, hospital stay, complication rates, and reoperation rates between MI-PCF and ACDF. However, when comparing CDA with MI-PCF, it was found that CDA had a higher complication rate, while MI-PCF had a higher reoperation rate.

Discussion and conclusion

Despite these findings, the study recommends MI-PCF as the preferred surgical method for cervical radiculopathy, owing to the advancements in minimally invasive techniques. However, these findings are preliminary, and further research with longer follow-up periods and larger sample sizes is necessary to confirm these findings and to further explore the potential advantages and disadvantages of these surgical methods.

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.

Evaluating the risk of return to the operating room across all elective orthopaedic procedures

BACKGROUND

Although elective procedures have life-changing potential, all surgeries come with an inherent risk of reoperation. There is a gap in knowledge investigating the risk of reoperation across orthopaedics. We aimed to identify the elective orthopaedic procedures with the highest rate of unplanned reoperation and the reasons for these procedures having such high reoperation rates.

METHODS

Patients in the NSQIP database were identified using CPT and ICD-10 codes. We isolated 612,815 orthopaedics procedures from 2018 to 2020 and identified the 10 CPT codes with the greatest rate of unplanned return to the operating room. For each index procedure, we identified the ICD-10 codes for the reoperation procedure and categorized them into infection, mechanical failure, fracture, wound disruption, hematoma or seroma, nerve pathology, other, and unspecified.

RESULTS

Below knee amputation (BKA) (CPT 27880) had the highest reoperation rate of 6.92% (37 of 535 patients). Posterior-approach thoracic (5.86%) or cervical (4.14%) arthrodesis and cervical laminectomy (3.85%), revision total hip arthroplasty (5.23%), conversion to total hip arthroplasty (4.33%), and revision shoulder arthroplasty (4.22%) were among the remaining highest reoperation rates. The overall leading causes of reoperation were infection (30.1%), mechanical failure (21.1%), and hematoma or seroma (9.4%) for the 10 procedures with the highest reoperation rates.

CONCLUSIONS

This study successfully identified the elective orthopaedic procedures with the highest 30-day return to OR rates. These include BKA, posterior thoracic and cervical spinal arthrodesis, revision hip arthroplasty, revision total shoulder arthroplasty, and cervical laminectomy. With this data, we can identify areas across orthopaedics in which revising protocols may improve patient outcomes and limit the burden of reoperations on patients and the healthcare system. Future studies should focus on the long-term physical and financial impact that these reoperations may have on patients and hospital systems.

LEVEL OF CLINICAL EVIDENCE

IV.

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.

Comparing outcomes between anterior cervical disc replacement (ACDR) and minimally invasive posterior cervical foraminotomy (MI-PCF) in the treatment of cervical radiculopathy

BACKGROUND CONTEXT

Anterior cervical disc replacement (ACDR) and minimally invasive posterior cervical foraminotomy (MI-PCF) have emerged as two increasingly popular alternatives to anterior cervical discectomy and fusion (ACDF) for the management of cervical radiculopathy. Both techniques provide advantages of segmental motion preservation and lower rates of adjacent segment degeneration (ASD) compared to ACDF.

PURPOSE

The purpose of this study was to analyze the clinical and functional outcomes of patients undergoing ACDR or MI-PCF for the treatment of unilateral cervical radiculopathy.

STUDY DESIGN/SETTING

Retrospective Cohort Review.

PATIENT SAMPLE

A total of 152 patients were included (86 ACDR and 66 MI-PCF).

OUTCOME MEASURES

(1) Patient demographics; (2) perioperative data; (3) rates of complications and revisions; (5) visual analogue scale (VAS) and Neck Disability Index (NDI) scores.

METHODS

A retrospective cohort review was performed to identify all patients at a single institution between 2012-2020 who underwent 1- or 2- level ACDR or MI-PCF from C3-C7 with a minimum follow-up of 24 months. Patient demographics, perioperative data, postoperative complications, and revisions were analyzed. Patient reported outcome measures including VAS and NDI scores were compared.

RESULTS

The ACDR group had a significantly greater mean operative time (99.8 minutes vs 79.2 minutes, p<.001), but comparable estimated blood loss and length of stay following surgical intervention (p=.899). The overall complication rate was significantly greater in the ACDR group than the MI-PCF group (24.4% vs 6.2%; p=.003) but was largely driven by approach-related dysphagia in 20.9% of ACDR patients. The MI-PCF group had significantly greater revision rates (13.6% vs 1.2%; p=.002) with an average time to revision of 20.7 months in the MI-PCF group compared to 40.3 months in the ACDR group. The ACDR cohort had significantly greater improvements in NDI scores at the final follow-up (25.0 vs 21.3, p<.001).

CONCLUSION

Our results suggest that ACDR offer clinically relevant advantages over MI-PCF in terms of long-term revision rates despite an increased approach-related risk of transient postoperative dysphagia. Additionally, patients in the ACDR cohort achieved greater mean improvements in NDI scores but these results may have limited clinical significance due to inability to reach minimally clinically important difference (MCID) thresholds.

Posterior Lateral Endoscopic Cervical Discectomy Through a Lateral Mass Approach in the Treatment of Cervical Spondylotic Radiculopathy

OBJECTIVE

The present study outlines the feasibility, safety, and short-term clinical outcomes of posterior lateral endoscopic cervical discectomy (PLECD) through a lateral mass approach for treating cervical spondylotic radiculopathy (CSR).

METHODS

This single-center retrospective observational study involved 30 patients with single-level CSR who had failed conservative treatment and presented with clinical symptoms consistent with imaging findings undergoing PLECD via a lateral mass approach. Primary outcomes included the visual analog scale (VAS) for neck and arm pain, the Japanese Orthopedic Association (JOA) score, and the modified MacNab criteria. Radiographic follow-up consisted of static and dynamic cervical radiographs and computed tomographic scans.

RESULTS

Thirty patients (13 men and 17 women; mean age 48.8 ± 11.9 years) underwent this procedure, and the mean operative time was 74.90 ± 13.52 minutes. Mean follow-up was 7.37 ± 2.17 months. The VAS scores for the neck and arm decreased significantly at the last follow-up (neck, 26.80 ± 4.75 to 9.87 ± 1.78; arm, 71.30 ± 8.48 to 14.73 ± 4.00) (P < 0.05). The JOA score also decreased from 13.47 ± 1.36 to 15.90 ± 0.92 at the last follow-up (P < 0.05). Twenty-nine patients demonstrated satisfactory outcomes based on the modified MacNab criteria at the last follow-up. All patients exhibited a positive clinical response, experiencing relief from symptoms. Postoperative computed tomography (CT) scans confirmed the complete removal of lesions.

CONCLUSIONS

PLECD through a lateral mass approach, as an alternative to conventional "keyhole" approaches, proves to be a novel and viable therapeutic option for CSR, demonstrating both high efficacy and safety.

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.

Multi-Level Posterior Cervical Foraminotomy Associated With Increased Post-operative Infection Rates and Overall Re-Operation Relative to Anterior Cervical Discectomy With Fusion or Cervical Disc Arthroplasty

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

Cervical radiculopathy meeting operative criteria has traditionally been managed using anterior cervical discectomy and fusion (ACDF). However, cervical disc arthroplasty (CDA) and posterior cervical foraminotomy (PCF) are also reasonable options. This study aimed to assess differences in postoperative outcomes among patients undergoing multi-level ACDF, CDA, or PCF comparing medical/surgical complications and healthcare utilization parameters.

METHODS

Patients who underwent multi-level ACDF, CDA, or PCF between 2012 and 2019 were identified from the American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP) database. Patients were stratified based on procedure type and propensity score matched to resolve baseline differences. ANOVA was performed to identify differences in medical complications, surgical complications, and healthcare utilization metrics.

RESULTS

A total of 31 344 patients who underwent an eligible procedure were identified (ACDF: n = 28 089, CDA: n = 1748, PCF: n = 1507), and 684 patients remained in each group following propensity score matching. Patients undergoing multi-level PCF were found to experience longer lengths of hospital stay (PCF: 1.67 ± 1.61 days, ACDF: 1.50 ± 1.32 days, CDA: 1.27 ± 1.05 days, P < .001), higher rates of reoperation (PCF: 3.2%, ACDF: 1.0%, CDA: .4%, P = .020), superficial infection (PCF: 1.3%, ACDF: .3%, CDA: .1%, P = .008) and deep infection (PCF: 1.2%, ACDF: 0%, CDA: 0%, P < .001). There were no outcome differences between multi-level ACDF and CDA.

CONCLUSIONS

Patients undergoing multi-level PCF were at increased risk for longer hospital stay, re-operation, and infection relative to those undergoing ACDF and CDA. Future research should aim to uncover the precise mechanisms underlying these complications, as well as analyze long term outcomes.

LEVEL OF EVIDENCE

III.

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.

Clinical and cost-effectiveness of PCF versus ACD in the treatment of cervical brachialgia (FORVAD trial)

BACKGROUND

Cervical radiculopathy occurs when a nerve root is compressed in the spine, if symptoms fail to resolve after 6 weeks surgery may be indicated. Anterior Cervical Discectomy (ACD) is the commonest procedure, Posterior Cervical Foraminotomy (PCF) is an alternative that avoids the risk of damage to anterior neck structures. This prospective, Phase III, UK multicentre, open, individually randomised controlled trial was performed to determine whether PCF is superior to ACD in terms of improving clinical outcome as measured by the Neck Disability Index (NDI) 52 weeks post-surgery.

METHOD

Following consent to participate and collection of baseline data, subjects with cervical brachialgia were randomised to ACD or PCF in a 1:1 ratio on the day of surgery. Clinical outcomes were assessed on day 1 and patient reported outcomes on day 1 and weeks 6, 12, 26, 39 and 52 post-operation. A total of 252 participants were planned to be randomised. Statistical analysis was limited to descriptive statistics. Health economic outcomes were also described.

RESULTS

The trial was closed early (n = 23). Compared to baseline, the median (interquartile range (IQR)) NDI score at 52 weeks reduced from 44.0 (36.0, 62.0) to 25.3 (20.0, 42.0) in the PCF group and increased from 35.6 (34.0, 44.0) to 45.0 (20.0, 57.0) in the ACD group. ACD may be associated with more swallowing, voice and other complications and was more expensive; neck and arm pain scores were similar.

CONCLUSIONS

The trial was closed early, therefore no definitive conclusions on clinical or cost-effectiveness could be made.

Patient-specific Cervical Deformity Corrections With Consideration of Associated Risk: Establishment of Risk Benefit Thresholds for Invasiveness Based on Deformity and Frailty Severity

STUDY DESIGN/SETTING

This was a retrospective cohort study.

BACKGROUND

Little is known of the intersection between surgical invasiveness, cervical deformity (CD) severity, and frailty.

OBJECTIVE

The aim of this study was to investigate the outcomes of CD surgery by invasiveness, frailty status, and baseline magnitude of deformity.

METHODS

This study included CD patients with 1-year follow-up. Patients stratified in high deformity if severe in the following criteria: T1 slope minus cervical lordosis, McGregor's slope, C2-C7, C2-T3, and C2 slope. Frailty scores categorized patients into not frail and frail. Patients are categorized by frailty and deformity (not frail/low deformity; not frail/high deformity; frail/low deformity; frail/high deformity). Logistic regression assessed increasing invasiveness and outcomes [distal junctional failure (DJF), reoperation]. Within frailty/deformity groups, decision tree analysis assessed thresholds for an invasiveness cutoff above which experiencing a reoperation, DJF or not achieving Good Clinical Outcome was more likely.

RESULTS

A total of 115 patients were included. Frailty/deformity groups: 27% not frail/low deformity, 27% not frail/high deformity, 23.5% frail/low deformity, and 22.5% frail/high deformity. Logistic regression analysis found increasing invasiveness and occurrence of DJF [odds ratio (OR): 1.03, 95% CI: 1.01-1.05, P =0.002], and invasiveness increased with deformity severity ( P <0.05). Not frail/low deformity patients more often met Optimal Outcome with an invasiveness index <63 (OR: 27.2, 95% CI: 2.7-272.8, P =0.005). An invasiveness index <54 for the frail/low deformity group led to a higher likelihood of meeting the Optimal Outcome (OR: 9.6, 95% CI: 1.5-62.2, P =0.018). For the frail/high deformity group, patients with a score <63 had a higher likelihood of achieving Optimal Outcome (OR: 4.8, 95% CI: 1.1-25.8, P =0.033). There was no significant cutoff of invasiveness for the not frail/high deformity group.

CONCLUSIONS

Our study correlated increased invasiveness in CD surgery to the risk of DJF, reoperation, and poor clinical success. The thresholds derived for deformity severity and frailty may enable surgeons to individualize the invasiveness of their procedures during surgical planning to account for the heightened risk of adverse events and minimize unfavorable outcomes.

Unilateral Biportal Endoscopic Posterior Cervical Foraminotomy: An Outcome Comparison With the Full-endoscopic Posterior Cervical Foraminotomy

STUDY DESIGN

Retrospective control study.

OBJECTIVE

To compare the curative effects of unilateral biportal endoscopic posterior cervical foraminotomy (UBE-PCF) with full-endoscopic posterior cervical foraminotomy (FPCF).

SUMMARY OF BACKGROUND DATA

There are few studies directly comparing outcomes between UBE-PCF and FPCF. The objective of this study was to compare outcomes between UBE-PCF and FPCF.

METHODS

A retrospective control study was conducted for 69 patients of cervical radiculopathy from July 2019 to December 2021. Clinical outcomes scores, including neck disability index, visual analog scale (VAS)-arm, and VAS-neck were evaluated. Serum creatine kinase levels and the size of the operating hole were measured.

RESULTS

Postoperative neck disability index, VAS-neck, and VAS-arm scores showed statistically significant improvement over preoperative scores ( P <0.01). The operating time was significantly shorter in the UBE-PCF group ( P <0.001). No significant differences were found in serum creatine kinase levels between the 2 groups ( P >0.05). The mean area of the operating hole was 1.47+0.05 cm 2 in the FPCF group and 1.79+0.11 cm 2 in the UBE-PCF group. The difference was statistically significant ( P <0.001).

CONCLUSIONS

Both UBE-PCF and FPCF are safe and effective procedures for cervical radiculopathy. Predictable and sufficient decompression could be achieved by UBE-PCF in a shorter operation time.

LEVEL OF EVIDENCE

Treatment Benefits Level III.

Anterior transcorporeal approach combined with posterior translaminar approach in percutaneous endoscopic cervical discectomy for two-segment cervical disc herniation treatment: a technical report and early follow-up

OBJECTIVE

Full endoscopic techniques are being gradually introduced from single-segment cervical disc herniation surgery to two-segment cervical disc herniation surgery. However, there is no suitable full endoscopic treatment for mixed-type two-segment cervical disc herniation (MTCDH) in which one segment herniates in front of the spinal cord and the other segment herniates behind the spinal cord. Therefore, we introduce a new full endoscopic technique by combining an anterior transcorporeal approach and a posterior translaminar approach. In addition, we provide a brief description of its safety, efficacy, feasibility, and surgical points.

METHODS

Thirty patients with MTCDH were given full endoscopic surgical treatment by a combined transcorporeal and transforaminal approach and were followed up for at least 12 months.

RESULTS

Clinical assessment scales showed that the patient's symptoms and pain were significantly reduced postoperatively. Imaging results showed bony repair of the surgically induced bone defect and the cervical Cobb angle was increased. No serious complications occurred.

CONCLUSION

This technique enables minimally invasive surgery to relieve the compression of the spinal cord by MTCDH. It avoids the fusion of the vertebral body for internal fixation, preserves the vertebral motion segments, avoids medical destruction of the cervical disc to the greatest extent possible, and expands the scope of adaptation of full endoscopic technology in cervical surgery.

Percutaneous Endoscopic Posterior Lateral Approach for the Treatment of Central Cervical Disc Herniation

BACKGROUND

To design percutaneous endoscopic surgery via a posterolateral approach for the treatment of central cervical disc herniation.

METHODS

From October 2019 to October 2020, 12 consecutive patients with central cervical disc herniation underwent percutaneous endoscopic posterior lateral cervical surgery. The imaging examination (dynamic X-ray, computed tomography, and magnetic resonance imaging of the cervical spine) was conducted after the operation. Visual analog scale score and the modified Japanese Orthopaedic Association score was performed before and after the operation.

RESULTS

Twelve patients (6 men and 6 women; mean age 52.08 ± 9.3 years) were included, and the average operation time was 105.00 ± 10.55 minutes. Postoperative computed tomography and magnetic resonance imaging results showed that the treatment segment of all patients was prominent, the cervical intervertebral disc was completely removed, the cervical spinal cord was fully decompressed, and there were no cases of infection, cerebrospinal fluid leakage or neurological complications. The average follow-up time after the operation was 22.83 ± 3.13 months. One year after the operation, there was no cervical instability in the X-ray examination of cervical flexion and extension position. Preoperative visual analog scale score and the modified Japanese Orthopaedic Association score were significantly improved at the last follow-up.

CONCLUSION

Percutaneous endoscopic posterior lateral cervical discectomy provides a new surgical method for the endoscopic treatment of central cervical disc herniation. This treatment has a better surgical field and easier operation, which can remove the protruding cervical disc under the endoscope and make sure that the cervical spinal cord is fully decompressed. The clinical effect is satisfactory. A small amount of pedicle resection will not cause cervical instability.

Cervical Conjoined Nerve Root During Posterior Percutaneous Endoscopic Cervical Diskectomy

Cervical conjoined nerve root is rare, and medical imaging, such as magnetic resonance imaging and computed tomography, cannot give an accurate preoperative diagnosis.1 Treatment of cervical radiculopathy with root anomaly can be challenging. We report here a case of cervical conjoined nerve root with a 2-dimensional video. A 41-year-old woman without systemic disease presented with a 2-month history of neck and bilateral shoulder pain, upper back tightness, and left upper limb painful numbness, especially of the first to third fingers. The visual analog scale scores of the neck and left upper limb were 4 and 8, respectively. The Neck Disability Index was 26. The diagnosis of retrolisthesis at C5-C6 and cervical disk herniation with severe neuroforaminal narrowing at the left C5-C6 and C6-C7 levels were made with radiographs and magnetic resonance imaging. Posterior percutaneous endoscopic cervical diskectomy at the left C5-C6 and C6-C7 levels via an interlaminar shoulder approach was performed. During operation, a left-sided conjoined nerve root at the C6-C7 level was found (Video 1). Upon removal of a calcified disk and osteophytes at the C6-C7 level, the dura was torn slightly with traction without nerve root exposure or cerebrospinal fluid leakage. The 3-month postoperative follow-up visual analog scale scores of the neck and left upper limb were 0 and 0, respectively. The 3-month postoperative follow-up Neck Disability Index was 1. Posterior percutaneous endoscopic cervical diskectomy has become a favored treatment for cervical disk herniation because it offers sufficient decompression, smaller incisions, minimal blood loss, shorter hospital stay, and less postoperative pain.2,3 Nonetheless, if unexpected variation of the nerve root is noted during decompressive procedures, iatrogenic nerve root injury is a risk. Seven cases of cervical nerve root anomalies have been reported; all were found during posterior cervical surgery, which may indicate that the posterior approach provides better visualization of nerve root variants, especially in endoscopic surgery.4.

Narrative Review of Uniportal Posterior Endoscopic Cervical Foraminotomy

Cervical radiculopathy is a common and disabling cervical condition characterized by symptoms including axial neck pain, radicular pain, weakness, and numbness in one or both arms. Common causes include herniated discs and foraminal stenosis, often accompanied by varying degrees of degenerative disc disease and uncovertebral joint hypertrophy. In the treatment of cervical radiculopathy, there is an increasing preference for posterior foraminotomy over anterior cervical discectomy and fusion due to the avoidance of fusion-related complications. As endoscopic spine surgery techniques continue to evolve, there is a rising interest in posterior endoscopic cervical foraminotomy and posterior endoscopic cervical discectomy as effective treatments for cervical radiculopathy. Because these procedures can performed through a single subcentimeter incision with minimal soft tissue damage, they can often be carried out as ambulatory procedures. In this narrative review, we examined current literature addressing the indications, surgical techniques, outcomes, and potential complications associated with posterior cervical endoscopic approaches.

Full-Endoscopic Technique for Posterior Fossa Decompression in Chiari Malformation

BACKGROUND AND IMPORTANCE

Full-endoscopic techniques are well-described for spinal procedures. Although endoscopic-assisted techniques are reported for posterior fossa decompression (PFD) in Chiari malformation (CM), a full-endoscopic technique is yet to be reported in these patients. The aim of this study was to present and describe a full-endoscopic technique for PFD in patients with CM.

CLINICAL PRESENTATION

Two patients diagnosed with CM were operated on by the full-endoscopic PFD technique. The patients consented to the procedure and to the publication of their image. An endoscope with an oval shaft cross-section with a diameter of 9.3 mm, a working length of 177 mm, a viewing angle of 20°, and a working channel of 5.6 diameters were used. Operative videos were recorded. The surgical steps were easily applied after the clear anatomic landmarks, such as the C1 posterior tubercle and the rectus capitis posterior minor muscles. The patients were followed up for 6 months. Both patients were symptom-free with a significant decrease in Visual Analog Scale score and a good functional outcome assessed by Chicago Chiari Outcome Scale after surgery without any complications.

CONCLUSION

All the steps of the full-endoscopic technique for PFD described by the authors in their previous human cadaveric study were also feasible on patients with CM.

Intracranial Pressure Evaluation in Swine During Full-Endoscopic Lumbar Spine Surgery

BACKGROUND

Neurological complications during full-endoscopic spine surgery (FESS) might be attributed to intracranial pressure (ICP) increase due to continuous saline infusion (CSI). Understanding CSI and ICP correlation might modify irrigation pump usage. This study aimed to evaluate invasive ICP during interlaminar FESS; correlate ICP with irrigation pump parameters (IPPs); evaluate ICP during saline outflow occlusion, commonly used to control bleeding and improve the surgeon's view; and, after durotomy, simulate accidental dural tear.

METHODS

Five swine were monitored, submitted to total intravenous anesthesia, and positioned ventrally. A parenchymal catheter was installed through a skull burr for ICP monitoring. Lumbar interlaminar FESS was performed until exposure of neural structures. CSI was used within progressively higher IPPs (A [60 mm Hg, 350 mL/minute] to D [150 mm Hg, 700 mL/minute]), and ICP was documented. During each IPP, different situations were grouped: intact dura with open channels (A1-D1) or occlusion test (A2-D2); dural tear with open channels (Ax1-Dx1) or occlusion test (Ax2-Dx2). ICP <20 mm Hg was defined as safe.

RESULTS

Basal average ICP was 8.1 mm Hg. Adjustment in total intravenous anesthesia or suspension of tests was necessary due to critical ICP or animal discomfort. It was safe to operate with all IPPs with opened drainage channels (A1-D1) even with dural tear (Ax1-Dx1). Several occlusion tests (A2-D2, Ax2-Dx2) caused ICP increase (e.g., 86.1 mm Hg) influenced by anesthetic state and hemodynamics.

CONCLUSIONS

During FESS, CSI might critically raise ICP. Keeping drainage channels open, with ideal anesthetic state, ICP remains safe even with high IPPs, despite dural tear. Drainage occlusions can quickly raise ICP, being even more severe with higher IPPs. Total intravenous anesthesia may protect from ICP increase and may allow longer drainage occlusion or higher IPPs.

Full Endoscopic Spine Surgery with Image-Guided Navigation System as "Hybrid Endoscopic Spine Surgery": A Narrative Review

Endoscopic surgery is adopted as a minimally invasive technique in several surgical fields. Endoscopic spine surgery (ESS) was performed initially for lumbar discectomy but is currently widely utilized for various pathologies. Similar to other endoscopic techniques, ESS has a steep learning curve that has recently been a topic of discussion. Image-guided navigation systems have been developed for spine surgery. Intraoperative computed tomography enables the use of an image-guided navigation system in ESS, which is a suitable approach for managing complex lesions. Full-ESS is currently being adopted for certain cervical pathologies, and the incorporation of an image-guided navigation system will soon enable surgery for other cervical pathologies.

Impact of Posterior Cervical Foraminotomy Before or After Cervical Disk Replacement: Current Evidence

STUDY DESIGN

Narrative review.

OBJECTIVES

The purpose of this study was to provide a review of the current evidence on the impact of posterior cervical foraminotomy (PCF) performed before or after cervical disk replacement (CDR).

SUMMARY OF BACKGROUND DATA

The impact of PCF on outcomes in the setting of CDR is an evolving field, given the recent widespread adoption of CDR and the relative rarity of patients who have undergone both procedures.

METHODS

A literature search was conducted using PubMed to determine current evidence regarding the indications, outcomes, and biomechanical effects of CDR and PCF when performed alone or in combination.

RESULTS

When radicular symptoms persist following PCF, a CDR can be safely performed to provide further decompression. Conversely, a PCF can be safely performed following CDR for these same indications. The biomechanical effects of these procedures in combination demonstrate maintained stability when the facetectomy is less than 50% of the facet joint. Studies demonstrate that stability is not significantly decreased by the presence, amount, or level of posterior foraminotomies in the setting of CDR.

CONCLUSIONS

A PCF can be safely performed before or after cervical disk arthroplasty for recurrent radicular symptoms.

LEVEL OF EVIDENCE

Level V.

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.

Advances and Evolving Challenges in Spinal Deformity Surgery

BACKGROUND

Surgical intervention is a critical tool to address adult spinal deformity (ASD). Given the evolution of spinal surgical techniques, we sought to characterize developments in ASD correction and barriers impacting clinical outcomes.

METHODS

We conducted a literature review utilizing PubMed, Embase, Web of Science, and Google Scholar to examine advances in ASD surgical correction and ongoing challenges from patient and clinician perspectives. ASD procedures were examined across pre-, intra-, and post-operative phases.

RESULTS

Several factors influence the effectiveness of ASD correction. Standardized radiographic parameters and three-dimensional modeling have been used to guide operative planning. Complex minimally invasive procedures, targeted corrections, and staged procedures can tailor surgical approaches while minimizing operative time. Further, improvements in osteotomy technique, intraoperative navigation, and enhanced hardware have increased patient safety. However, challenges remain. Variability in patient selection and deformity undercorrection have resulted in heterogenous clinical responses. Surgical complications, including blood loss, infection, hardware failure, proximal junction kyphosis/failure, and pseudarthroses, pose barriers. Although minimally invasive approaches are being utilized more often, clinical validation is needed.

CONCLUSIONS

The growing prevalence of ASD requires surgical solutions that can lead to sustained symptom resolution. Leveraging computational and imaging advances will be necessary as we seek to provide comprehensive treatment plans for patients.

Posterior cervical foraminotomy versus anterior cervical discectomy for Cervical Brachialgia: the FORVAD RCT

Background

Posterior cervical foraminotomy and anterior cervical discectomy are routinely used operations to treat cervical brachialgia, although definitive evidence supporting superiority of either is lacking.

Objective

The primary objective was to investigate whether or not posterior cervical foraminotomy is superior to anterior cervical discectomy in improving clinical outcome.

Design

This was a Phase III, unblinded, prospective, United Kingdom multicentre, parallel-group, individually randomised controlled superiority trial comparing posterior cervical foraminotomy with anterior cervical discectomy. A rapid qualitative study was conducted during the close-down phase, involving remote semistructured interviews with trial participants and health-care professionals.

Setting

National Health Service trusts.

Participants

Patients with symptomatic unilateral cervical brachialgia for at least 6 weeks.

Interventions

Participants were randomised to receive posterior cervical foraminotomy or anterior cervical discectomy. Allocation was not blinded to participants, medical staff or trial staff. Health-care use from providing the initial surgical intervention to hospital discharge was measured and valued using national cost data.

Main outcome measures

The primary outcome measure was clinical outcome, as measured by patient-reported Neck Disability Index score 52 weeks post operation. Secondary outcome measures included complications, reoperations and restricted American Spinal Injury Association score over 6 weeks post operation, and patient-reported Eating Assessment Tool-10 items, Glasgow-Edinburgh Throat Scale, Voice Handicap Index-10 items, PainDETECT and Numerical Rating Scales for neck and upper-limb pain over 52 weeks post operation.

Results

The target recruitment was 252 participants. Owing to slow accrual, the trial closed after randomising 23 participants from 11 hospitals. The qualitative substudy found that there was support and enthusiasm for the posterior cervical FORaminotomy Versus Anterior cervical Discectomy in the treatment of cervical brachialgia trial and randomised clinical trials in this area. However, clinical equipoise appears to have been an issue for sites and individual surgeons. Randomisation on the day of surgery and processes for screening and approaching participants were also crucial factors in some centres. The median Neck Disability Index scores at baseline (pre surgery) and at 52 weeks was 44.0 (interquartile range 36.0-62.0 weeks) and 25.3 weeks (interquartile range 20.0-42.0 weeks), respectively, in the posterior cervical foraminotomy group (n = 14), and 35.6 weeks (interquartile range 34.0-44.0 weeks) and 45.0 weeks (interquartile range 20.0-57.0 weeks), respectively, in the anterior cervical discectomy group (n = 9). Scores appeared to reduce (i.e. improve) in the posterior cervical foraminotomy group, but not in the anterior cervical discectomy group. The median Eating Assessment Tool-10 items score for swallowing was higher (worse) after anterior cervical discectomy (13.5) than after posterior cervical foraminotomy (0) on day 1, but not at other time points, whereas the median Glasgow-Edinburgh Throat Scale score for globus was higher (worse) after anterior cervical discectomy (15, 7, 6, 6, 2, 2.5) than after posterior cervical foraminotomy (3, 0, 0, 0.5, 0, 0) at all postoperative time points. Five postoperative complications occurred within 6 weeks of surgery, all after anterior cervical discectomy. Neck pain was more severe on day 1 following posterior cervical foraminotomy (Numerical Rating Scale - Neck Pain score 8.5) than at the same time point after anterior cervical discectomy (Numerical Rating Scale - Neck Pain score 7.0). The median health-care costs of providing initial surgical intervention were £2610 for posterior cervical foraminotomy and £4411 for anterior cervical discectomy.

Conclusions

The data suggest that posterior cervical foraminotomy is associated with better outcomes, fewer complications and lower costs, but the trial recruited slowly and closed early. Consequently, the trial is underpowered and definitive conclusions cannot be drawn. Recruitment was impaired by lack of individual equipoise and by concern about randomising on the day of surgery. A large prospective multicentre trial comparing anterior cervical discectomy and posterior cervical foraminotomy in the treatment of cervical brachialgia is still required.

Trial registration

This trial is registered as ISRCTN10133661.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 21. See the NIHR Journals Library website for further project information.

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.

Single-level Anterior Cervical Discectomy and Fusion Results in Lower Five-year Revisions than Posterior Cervical Foraminotomy in a Large National Cohort

STUDY DESIGN

A retrospective cohort study using the 2010-2020 MSpine PearlDiver administrative data set.

OBJECTIVE

To compare perioperative adverse events and five-year revisions for single-level anterior cervical discectomy and fusion (ACDF) versus posterior cervical foraminotomy (PCF).

SUMMARY OF BACKGROUND DATA

Cervical disk disease can often be treated surgically using single-level ACDF or PCF. Prior studies have suggested that posterior approaches provide similar short-term outcomes as ACDF; however, posterior procedures may have an increased risk of revision surgery.

MATERIALS AND METHODS

The database was queried for patients undergoing elective single-level ACDF or PCF (excluding cases performed for myelopathy, trauma, neoplasm, and/or infection). Outcomes, including specific complications, readmission, and reoperations, were assessed. Multivariable logistic regression was used to ascertain odds ratios (OR) of 90-day adverse events controlling for age, sex, and comorbidities. Kaplan-Meier survival analysis was performed to determine five-year rates of cervical reoperation in the ACDF and PCF cohorts.

RESULTS

A total of 31,953 patients treated by ACDF (29,958, 93.76%) or PCF (1995, 6.24%) were identified. Multivariable analysis, controlling for age, sex, and comorbidities, demonstrated that PCF was associated with significantly greater odds of aggregated serious adverse events (OR 2.17, P <0.001), wound dehiscence (OR 5.89, P <0.001), surgical site infection (OR 3.66, P <0.001), and pulmonary embolism (OR 1.72, P =0.04). However, PCF was associated with significantly lower odds of readmission (OR 0.32, P <0.001), dysphagia (OR 0.44, P <0.001), and pneumonia (OR 0.50, P =0.004). At five years, PCF cases had a significantly higher cumulative revision rate compared with ACDF cases (19.0% vs. 14.8%, P <0.001).

CONCLUSIONS

The current study is the largest to date to compare short-term adverse events and five-year revision rates between single-level ACDF and PCF for nonmyelopathy elective cases. Perioperative adverse events differed by procedure, and it was notable that the incidence of cumulative revisions was higher for PCF. These findings can be used in decision-making when there is clinical equipoise between ACDF and PCF.

Full-endoscopic anterior excision of thoracic disc herniations, including giant and calcified discs with spinal cord compression: surgical technique and outcomes

PURPOSE

Operations on thoracic herniated discs are comparatively rare and often demanding. An individual approach and mastery of different surgical techniques and surgical approaches are necessary. The main factors for the chosen surgical technique and approach are the anatomical localization, consistency of the pathology, the general condition of the patient and the experience of the surgeon. The purpose of this study was to evaluate the technical possibilities and outcomes of the full-endoscopic technique with interlaminar, extraforaminal and transthoracic retropleural approaches in patients with symptomatic herniated discs with anterior neural compression.

METHODS

In 49 patients with thoracic disc herniations, decompression was performed between 2016 and 2020, using a full-endoscopic interlaminar, extraforaminal or transthoracic retropleural approach. Clinical data and imaging were collected during follow-up of 18 months.

RESULTS

Sufficient decompression was achieved in all cases with the full-endoscopic surgical technique. Two patients experienced worsening of myelopathy, one of which was of transient duration, and one patient required reoperation for an epidural hematoma. No other complications were recorded. All other patients experienced a regression or improvement of symptoms.

CONCLUSION

The full-endoscopic technique with interlaminar, extraforaminal or transthoracic retropleural approach is a sufficient and minimally invasive method. All three full-endoscopic approaches of the thoracic spine are required to enable sufficient decompression of the anterior pathologies examined here.

Comparison of Single-level Cervical Radiculopathy Outcomes Between Posterior Endoscopic Cervical Decompression and Anterior Cervical Discectomy and Fusion: Mid-term Results

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To investigate the mid-term results and technical possibilities of posterior endoscopic cervical decompression (PECD) in the treatment of cervical radiculopathy.

SUMMARY OF BACKGROUND DATA

PECD has been used in the treatment of cervical radiculopathy for the past decades; there is a paucity of studies directly comparing its outcomes with anterior cervical discectomy and fusion (ACDF) for patients with single-level cervical radiculopathy.

PATIENTS AND METHODS

From January 2016 to December 2018, clinical and radiologic data of 42 patients were collected. Patients were followed for a mean of 40.6 months (range: 30-54 mo) after surgery. Changes in cervical lordosis and degeneration of adjacent segments were analyzed. Dysphagia was assessed using the Bazaz score, and clinical outcomes were analyzed using the Neck Disability Index and visual analog scoring system.

RESULTS

There were no significant differences in neurological outcomes between the two groups. Significant between-group differences in postoperative dysphagia were observed ( P < 0.05). There were significant differences in postoperative segmental Cobb angles and disc height between the two groups ( P < 0.05). Degenerative changes in the adjacent segments occurred in 5 patients in the ACDF group and 1 patient in the PECD group ( P < 0.05); no revision surgery was needed.

CONCLUSIONS

Clinical outcomes of PECD for patients with unilateral radiculopathy were satisfactory. On the premise of a strict selection of indications, we consider this technique to be a safe supplement and alternative to ACDF for patients with unilateral cervical radiculopathy. Longer follow-up periods are required to confirm these observations.

Clinical and Radiological Outcomes of a Comparative Study of Anterior Cervical Decompression and Fusion with Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) for Cervical Foraminal Pathology

Background and Objectives: The purpose was to compaSre medium-term clinical and radiological outcomes of Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) surgery versus Anterior Cervical Discectomy and Fusion (ACDF) for patients with cervical disc herniations and foraminal pathologies. Materials and Methods: A prospective registry of patients who had undergone either PPPV PECD surgery or ACDF surgery for cervical disc herniation or foraminal pathologies under a single fellowship-trained spine surgeon was performed. The baseline characteristics and operative details including complications were recorded for all included patients. The clinical outcomes evaluated include VAS, MJOA, motor score, and NDI and MacNab's score. The radiological parameters in neutral-measured facet length, facet area, disc height, C2-C7 angle, neck tilt angle, T1 slope and thoracic inlet angle were also evaluated. Results: A total of 55 patients (29 PPPV PECD, 26 ACDF) were included, with mean follow-up periods of 21.9 and 32.3 months, respectively. Each cohort was noted to have a single case of surgical complication. Statistically significant changes of facet area (49.05 ± 14.50%) and facet length (52.71 ± 15.11%) were noted in the PPPV PECD group. At neutral alignment of the neck on a lateral X-ray, compared to ACDF, PPPV PECD had a statistically significant change in neck tilt angle (-11.68 ± 17.35°) and T1 slope angle (-11.69 ± 19.58°). Whilst both PPPV PECD and ACDF had significant improvements in VAS, MJOA and NDI postoperatively, PPPV PECD was found to be superior across all above scores at various follow-up timepoints compared to its ACDF counterparts. Conclusions: PPPV PECD surgery achieved a satisfactory radiological correction of neck alignment and significantly improved clinical outcomes at medium-term follow-up for our cohort of patients, highlighting its feasibility in treating patients with cervical disc herniations and foraminal pathologies.

Full endoscopic spine surgery

Background

With a dramatic increase in elderly population worldwide, the prevalence of degenerative spine disease is steadily rising. Even though the entire spinal column is affected the problem is more commonly seen in the lumbar, cervical spine and to some extent the thoracic spine. The treatment of symptomatic lumbar disc or stenosis is primarily conservative with analgesics, epidural steroids and physiotherapy. Surgery is advised only if conservative treatment is ineffective. Conventional open microscopic procedures even though are still a gold standard, have the disadvantages of excessive muscle damage and bone resection, epidural scarring along with prolonged hospital stay and increased need of postoperative analgesics. Minimal access spine surgeries minimize surgical access related injury by minimizing soft tissue and muscle damage and also bony resection thus preventing iatrogenic instability and unnecessary fusions. This leads to good functional preservation of the spine and enhances early postoperative recovery and early return to work. Full endoscopic spine surgeries are one of the more sophisticated and advanced form of MIS surgeries.

Purpose

Full endoscopy has definitive benefits over conventional microsurgical techniques. These include better and clear vision of the pathology due to presence of irrigation fluid channel, minimal soft tissue and bone trauma, better and relatively easy approach to deep seated pathologies like thoracic disc herniations and a possibility to avoid fusion surgeries. The purpose of this article is to describe these benefits, give an overview of the two main approaches - transforaminal and interlaminar, their indications, contraindications and their limitations. The article also describes about the challenges in overcoming the learning curve and its future prospectives.

Conclusion

Full endoscopic spine surgery is one of the fastest growing technique in the field of modern spine surgery. Better intraoperative visualization of the pathology, lesser incidence of complications, faster recovery time, less postoperative pain, better relief of symptoms and early return to activity are the main reasons behind this rapid growth. With better patient outcomes and reduced medical costs, the procedure is going to be more accepted, relevant and popular procedure in future.

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.

Background, techniques, applications, current trends, and future directions of minimally invasive endoscopic spine surgery: A review of literature

Across many of the surgical specialties, the use of minimally invasive techniques that utilize indirect visualization has been increasingly replacing traditional techniques which utilize direct visualization. Arthroscopic surgery of the appendicular skeleton has evolved dramatically and become an integral part of musculoskeletal surgery over the last several decades, allowing surgeons to achieve similar or better outcomes, while reducing cost and recovery time. However, to date, the axial skeleton, with its close proximity to critical neural and vascular structures, has not adopted endoscopic techniques at as rapid of a rate. Over the past decade, increased patient demand for less invasive spine surgery combined with surgeon desire to meet these demands has driven significant evolution and innovation in endoscopic spine surgery. In addition, there has been an enormous advancement in technologies that assist in navigation and automation that help surgeons circumvent limitations of direct visualization inherent to less invasive techniques. There are currently a multitude of endoscopic techniques and approaches that can be utilized in the treatment of spine disorders, many of which are evolving rapidly. Here we present a review of the field of endoscopic spine surgery, including the background, techniques, applications, current trends, and future directions, to help providers gain a better understanding of this growing modality in spine surgery.

Full-endoscopic discectomy for thoracic disc herniations: a single-arm meta-analysis of safety and efficacy outcomes

INTRODUCTION

Surgical intervention is the treatment of choice in patients with thoracic disc herniation with refractory symptoms and progressive myelopathy. Due to high occurrence of complications from open surgery, minimally invasive approaches are desirable. Nowadays, endoscopic techniques have become increasingly popular and full-endoscopic surgery can be performed in the thoracic spine with low complication rates.

METHODS

Cochrane Central, PubMed, and Embase databases were systematically searched for studies that evaluated patients who underwent full-endoscopic spine thoracic surgery. The outcomes of interest were dural tear, myelopathy, epidural hematoma, recurrent disc herniation, and dysesthesia. In the absence of comparative studies, a single-arm meta-analysis was performed.

RESULTS

We included 13 studies with a total of 285 patients. Follow-up ranged from 6 to 89 months, age from 17 to 82 years, with 56.5% male. The procedure was performed under local anesthesia with sedation in 222 patients (77.9%). A transforaminal approach was used in 88.1% of the cases. There were no cases of infection or death reported. The data showed a pooled incidence of outcomes as follows, with their respective 95% confidence intervals (CI)-dural tear (1.3%; 95% CI 0-2.6%); dysesthesia (4.7%; 95% CI 2.0-7.3%); recurrent disc herniation (2.9%; 95% CI 0.6-5.2%); myelopathy (2.1%; 95% CI 0.4-3.8%); epidural hematoma (1.1%; 95% CI 0.2-2.5%); and reoperation (1.7%; 95% CI 0.1-3.4%).

CONCLUSION

Full-endoscopic discectomy has a low incidence of adverse outcomes in patients with thoracic disc herniations. Controlled studies, ideally randomized, are warranted to establish the comparative efficacy and safety of the endoscopic approach relative to open surgery.

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.

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.

Learning curve for biportal endoscopic posterior cervical foraminotomy determined using the cumulative summation test

BACKGROUND

Learning curves describe the rate of performance improvements corresponding to the surgeon's caseload, followed by a plateau where limited further improvements are observed. This study aimed to determine the learning curve for biportal full-endoscopic posterior cervical foraminotomy (BE-PCF) for the unilateral cervical foraminal disc.

METHODS

The learning curve was evaluated using a learning curve cumulative summation test (LC-CUSUM). The goal for the operation time was set to 78 min, which is the mean operation time (mOT) of percutaneous full-endoscopic posterior cervical foraminotomy (PE-PCF) performed by a senior surgeon. Moreover, clinical outcomes and post-operative complications were compared between the early and late learning periods 1 year post-operatively.

RESULTS

This study enrolled the first 50 patients who underwent single-level BE-PCF, performed by a single surgeon. The LC-CUSUM signalled competency for surgery at the 20th operation, indicating that sufficient evidence was obtained to prove that the surgeon was competent. The mOT was 71.29 ± 11.69 min in BE-PCF, 71.84 ± 12.61 min in the early learning period, and 67.83 ± 10.31 min in the late learning period (p = 0.254). There was no statistical difference in clinical outcomes, visual analogue scale scores, and neck disability index between both periods (p > 0.05). Four complications were recorded throughout the whole period, with three in the early period and one in the late period (p = 0.285).

CONCLUSION

Our study shows that BE-PCF has a learning curve of 20 caseloads to achieve 90% proficiency, and it significantly reduces the operation time based on the performance of a senior surgeon proficient in PE-PCF.

Comparison of Outcomes between Unilateral Biportal Endoscopic and Percutaneous Posterior Endoscopic Cervical Keyhole Surgeries

Objective: The purpose of this study was to compare the clinical and radiological outcomes of unilateral biportal endoscopic (UBE) and percutaneous posterior endoscopic cervical discectomy (PE) keyhole surgeries. Methods: Patients diagnosed with cervical spondylotic radiculopathy (CSR) treated by UBE or PE keyhole surgery from May 2017 to April 2020 were retrospectively analyzed. The length of incision, fluoroscopic time, postoperative hospital stay, and total cost were compared. The clinical efficacy was assessed using a visual analog scale (VAS), neck disability index (NDI), and modified MacNab criteria. Moreover, the C2-7 Cobb’s angle, range of motion (ROM), intervertebral height, vertebral horizontal displacement, and angular displacement of the surgical segment were measured. Results: A total of 154 patients were enrolled, including 89 patients in the UBE group and 65 patients in the PE group, with a follow-up period of 24–32 months. Compared with PE surgery, UBE surgery required shorter fluoroscopic times (6.76 ± 1.09 vs. 8.31 ± 1.10 s) and operation times (77.48 ± 17.37 vs. 84.92 ± 21.97 min) but led to higher total hospitalization costs and longer incisions. No significant differences were observed in the postoperative hospital stay, bleeding volume, VAS score, NDI score, effective rate, or complication rate between the UBE and PE groups. Both the C2-7 Cobb’s angle and ROM increased significantly after surgery, with no significant differences between groups. There were no significant differences between intervertebral height, vertebral horizontal displacement, and angular displacement of the surgical segment at different times. Conclusions: Both UBE and PE surgeries in the treatment of CSR were effective and similar after 24 months. The fluoroscopic and operation times of UBE were shorter than those of PE.

Full-endoscopic spine surgery diminishes surgical site infections - a propensity score-matched analysis

BACKGROUND CONTEXT

Surgical site infections (SSI) are one the most frequent and costly complications following spinal surgery. The SSI rates of different surgical approaches need to be analyzed to successfully minimize SSI occurrence.

PURPOSE

The purpose of this study was to define the rate of SSIs in patients undergoing full-endoscopic spine surgery (FESS) and then to compare this rate against a propensity score-matched cohort from the National Surgical Quality Improvement Program (NSQIP) database.

DESIGN

This is a retrospective multicenter cohort study using a propensity score-matched analysis of prospectively maintained databases.

PATIENT SAMPLE

One thousand two hundred seventy-seven non-instrumented FESS cases between 2015 and 2021 were selected for analysis. In the nonendoscopic NSQIP cohort we selected data of 55,882 patients.

OUTCOME MEASURES

The occurrence of any SSI was the primary outcome. We also collected any other perioperative complications, demographic data, comorbidities, operative details, history of smoking, and chronic steroid intake.

METHODS

All FESS cases from a multi-institutional group that underwent surgery from 2015 to 2021 were identified for analysis. A cohort of cases for comparison was identified from the NSQIP database using Current Procedural Terminology of nonendoscopic cervical, thoracic, and lumbar procedures from 2015 to 2019. Trauma cases as well as arthrodesis procedures, surgeries to treat pathologies affecting more than 4 levels or spine tumors that required surgical treatment were excluded. In addition, nonelective cases, and patients with wounds worse than class 1 were also not included. Patient demographics, comorbidities, and operative details were analyzed for propensity matching.

RESULTS

In the non-propensity-matched dataset, the endoscopic cohort had a significantly higher incidence of medical comorbidities. The SSI rates for nonendoscopic and endoscopic patients were 1.2% and 0.001%, respectively, in the nonpropensity match cohort (p-value <.011). Propensity score matching yielded 5936 nonendoscopic patients with excellent matching (standard mean difference of 0.007). The SSI rate in the matched population was 1.1%, compared to 0.001% in endoscopic patients with an odds ratio 0.063 (95% confidence interval (CI) 0.009-0.461, p=.006) favoring FESS.

CONCLUSIONS

FESS compares favorably for risk reduction in SSI following spinal decompression surgeries with similar operative characteristics. As a consequence, FESS may be considered the optimal strategy for minimizing SSI morbidity.

Posterior cervical full-endoscopic technique for the treatment of cervical spondylotic radiculopathy with foraminal bony stenosis: A retrospective study

Objective

In the treatment of cervical spondylotic radiculopathy (CSR), spinal endoscopy has been developed vigorously in the past 30 years. However, its effectiveness and subsequent problem of cervical spine stability have always been the controversial hotspots. This study aims to conduct a retrospective study using posterior cervical full-endoscopic technique for the treatment of CSR with foraminal bony stenosis, and evaluate its clinical effect and application value.

Methods

All 22 patients treated for CSR with foraminal bony stenosis using posterior cervical full-endoscopic technique were analyzed since Dec 1, 2016, to Apr 30, 2020. The data collection included operation time, length of stay, wound healing, surgical complications, visual analog scale (VAS), Japanese Orthopaedic Association (JOA) scores, intervertebral foramen diameter, intervertebral foramen area and cervical instability. The relevant indicators were observed on admission, at postoperative 1 week and 3 months, and at the last follow-up.

Results

The operation time was 141.6 ± 13.7 min. The length of stay was 6.0 ± 2.5 days. VAS and JOA at different time points after operation were decreased compared with before operation (p < 0.05). There were no statistical differences between VAS or JOA at different postoperative time points (p > 0.05). The height, anteroposterior diameter and area of intervertebral foramen after operation were significantly increased compared with before operation (p < 0.05).

Conclusion

Posterior cervical full-endoscopic technique shows the advantages of smaller invasion, faster recovery, significant effectiveness and fewer complications in our study. Meanwhile, it has little influence on the ROM and stability of the cervical spine. Therefore, it is a minimally invasive, safe and effective surgical method for the treatment of CSR with foraminal bony stenosis.

Cervical kinematic change after posterior full-endoscopic cervical foraminotomy for disc herniation or foraminal stenosis

OBJECTIVE

Posterior full-endoscopic cervical foraminotomy (PECF) is one of minimally invasive surgical techniques for cervical radiculopathy. Because of minimal disruption of posterior cervical structures, such as facet joint, cervical kinematics was minimally changed. However, a larger resection of facet joint is required for cervical foraminal stenosis (FS) than disc herniation (DH). The objective was to compare the cervical kinematics between patients with FS and DH after PECF.

METHODS

Consecutive 52 patients (DH, 34 vs. FS, 18) who underwent PECF for single-level radiculopathy were retrospectively reviewed. Clinical parameters (neck disability index, neck pain and arm pain), and segmental, cervical and global radiological parameters were compared at postoperative 3, 6, and 12 months, and yearly thereafter. A linear mixed-effect model was used to assess interactions between groups and time. Any occurrence of significant pain during follow-up was recorded during a mean follow-up period of 45.5 months (range 24-113 months).

RESULTS

Clinical parameters improved after PECF, with no significant differences between groups. Recurrent pain occurred in 6 patients and surgery (PECF, anterior discectomy and fusion) was performed in 2 patients. Pain-free survival rate was 91% for DH and 83% for FS, with no significant difference between the groups (P = 0.29). Radiological changes were not different between groups (P > 0.05). Segmental neutral and extension curvature became more lordotic. Cervical curvature became more lordotic on neutral and extension X-rays, and the range of cervical motion increased. The mismatch between T1-slope and cervical curvature decreased. Disc height did not change, but the index level showed degeneration at postoperative 2 years.

CONCLUSION

Clinical and radiological outcomes after PECF were not different between DH and FS patients and kinematics were significantly improved. These findings may be informative in a shared decision-making process.

Unilateral biportal endoscopic foraminotomy and diskectomy combined with piezosurgery for treating cervical spondylotic radiculopathy with neuropathic radicular pain

Objective

Unilateral biportal endoscopy (UBE) represents a relatively recent development in minimally invasive spine surgery. This study aimed to evaluate the efficacy and safety of UBE foraminotomy and diskectomy combined with piezosurgery for treating cervical spondylotic radiculopathy (CSR) with neuropathic radicular pain.

Methods

We retrospectively analyzed the outcomes in 12 patients with CSR who underwent UBE foraminotomy and diskectomy combined with piezosurgery. The intraoperative blood loss, operative time, visual analog scale (VAS) scores for the neck and arm, neck disability index (NDI) scores, and complications were recorded.

Results

Postoperative VAS scores of the neck and arm and NDI scores were significantly improved. Additionally, a postoperative CT scan revealed adequate enlargement of the cervical canal and nerve root. No specific complications occurred during surgery and the immediate postoperative period.

Conclusions

This primary study indicated that the UBE foraminotomy and diskectomy with piezosurgery is a promising technique for treating cervical spondylotic radiculopathy with neuropathic radicular pain.

Minimally invasive posterior cervical foraminotomy versus anterior cervical discectomy and fusion for cervical radiculopathy: a meta-analysis

With the recent development of minimally invasive techniques, minimally invasive posterior cervical foraminotomy (MIS-PCF) has become increasingly popular as a minimally invasive method to treat cervical radiculopathy. However, there are still controversies about whether MIS-PCF is superior to anterior cervical discectomy and fusion (ACDF). The purpose of this study is to evaluate the therapeutic effects of MIS-PCF and ACDF on unilateral cervical radiculopathy without myelopathy. We searched PubMed, Embase, the Cochrane Library, and Scopus comprehensively using the terms related to MIS-PCF. Two reviewers independently evaluated the potential studies, and extracted and analyzed the data of operation time, hospital stay, neck disability index (NDI) score, visual analog scale for neck pain (VAS-neck) and arm pain (VAS-arm) scores, reoperation rate, and complications. Seven studies with 1175 patients were included. The study population was 53.5% male, with a mean age of 48.9. MIS-PCF presented a significantly shorter postoperative hospitalization time compared to ACDF, while the operation time, complication/reoperation rate, and VAS-arm, VAS-neck, and NDI scores were comparable between the two cohorts. In North America, the average cost of MIS-PCF is lower than ACDF. Thus, we suggest that MIS-PCF is an alternative to ACDF for selected patients.

Size matters - From the working channel to the wavelength of light: Optimizing visualization in endoscopic spine surgery

BACKGROUND

Minimally invasive surgery bases many of its benefits on decreasing tissue disruption. Endoscopic spine surgery has continued to push the boundaries to accomplish successful clinical outcomes through the evolution of the endoscope and working channel. As the indications for endoscopic spine surgery increase, a more profound discussion of cannula size selection for endoscopic spine surgery is required. The intimate relationship between the working channel, the endoscope and how these choices affect workflow and visualization are paramount to maximize outcomes.

METHODS

The authors review the nuances of the endoscopic approaches to the various regions of the spine as it relates to the selection of the working channel. The advantages and limitations of various endoscopic working channels were analyzed as to how they address anatomic regional considerations as well as ultimate goals of surgery.

RESULTS

In addition to anatomic regional differences and the goals of the surgery other key elements in endoscopic working channel selection included the amount of tissue disruption, regional risk to the neural elements, impact on visualization, optical physics, and the implications for surgical maneuverability/dexterity.

CONCLUSION

Understanding the role and use of the endoscope-working channel combination with its effects on visualization is essential for any surgeon aspiring to perform safe and efficient full endoscopic spine surgery.