Full endoscopic lumbar interbody fusion (FELIF): technical note

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.

Full-Endoscopic Posterior Lumbar Interbody Fusion: A Review and Technical Note

Remarkable innovations in spinal endoscopic surgery have broadened its applications over the past 20 years. Full-endoscopic fusions have been widely reported, and several full-endoscopic approaches for interbody fusion have been published. In general, full-endoscopic lumbar interbody fusion (LIF) is called Endo-LIF, and facet-preserving Endo-LIF through the transforaminal route is called trans-Kambin's triangle LIF, which has a relatively longer history than facet-sacrificing Endo-LIF via the posterolateral route. Both approaches can reduce intraoperative and postoperative bleeding. However, there is a higher risk of subsidence and exit nerve root injury. There is no direct decompression in either of the interbody fusions, and additional decompression is required if there is severe lumbar bony canal stenosis. However, the posterior interlaminar approach, which is a well-known standard in full-endoscopic spine surgery, has rarely been applied in the field of endoscopic lumbar fusion surgery. Full-endoscopic posterior LIF (FE-PLIF) via an interlaminar approach can accomplish direct decompression of bony canal stenosis and safe interbody fusion. FE-PLIF via an interlaminar approach demonstrated a longer operation time, less blood loss, and shorter hospitalization duration than minimally invasive transforaminal LIF. FE-PLIF, which can accomplish direct decompression for bony spinal canal stenosis, is superior to other Endo-LIFs. However, FE-PLIF requires technical dexterity to improve efficiency and reduce technical complexity.

Optimizing Disc and Cartilage Endplate Preparation in Full-Endoscopic Lumbar Interbody Fusion: An In-Depth Exploration of Surgical Instruments with a Technique Note and Narrative Review

Full-endoscopic lumbar interbody fusion (FELIF) is a critical yet challenging procedure. However, extensive analyses of discectomy and cartilage endplate preparation techniques are limited. This can be attributed to the lack of universal protocols owing to diverse surgical practices and equipment preferences. Therefore, this narrative review presents a comprehensive overview of discectomy and cartilage endplate preparation techniques in FELIF. A literature search of the PubMed, Embase, and Google Scholar databases in December 2023 retrieved 490 studies, of which 53 met the predefined inclusion criteria, and 1373 patients were included in the analyses. Spinal endoscopic disc and cartilage endplate removal can be categorized into 2 main types: removal under direct endoscopic visualization and removal under radiographic guidance with the protection of a working sheath following the endoscope's removal. Removal under direct visualization ensures the safety and precision of the procedure. Radiographic guidance can enhance the efficiency of the removal process. Specially designed instruments can be utilized through the narrow working channels of spinal endoscopes for the scraping surgery. Moreover, many traditional spinal endoscopic instruments, through specific techniques and manipulations, can also aid in cartilage removal. The approaches and techniques vary significantly among physicians, but overall, these instruments and techniques aim to achieve a safe and efficient disc-scraping outcome. Thus, this review may offer a comprehensive guidance to surgeons in selecting the most efficient practices for FELIF. Uniform procedural protocols are needed to ensure broader adoption and standardized practice.

Comparison of Endoscopic and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Diseases: A Meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

To compare the results of endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for patients with lumbar degenerative diseases.

SUMMARY OF BACKGROUND DATA

The MIS-TLIF has been widely used in lumbar degenerative diseases and achieved favorable clinical effects. The main disadvantage is the limited working space and visualization, especially in the deeper operational field, for preparing fusion bed. In recent years, with the development of surgical techniques, optical technology, and special instruments, Endo-TLIF has gradually been applied.

MATERIALS AND METHODS

A systematic review and meta-analysis of cohort studies between Endo-TLIF and MIS-TLIF in the lumbar degenerative diseases. The following outcome measures were extracted: visual analog scale (VAS), Oswestry Disability Index, fusion rate, disk height, segmental lordosis, operative time, length of hospital stay and complications. Data analysis was performed by RevMan 5.3.

RESULTS

Eight studies comprising 687 patients were included in this meta-analysis. The pooled result revealed there was no significant differences in the VAS of leg, Oswestry Disability Index, fusion rate, disk height, segmental lordosis, and complication rate between the 2 groups ( P >0.05). However, the VAS of back in the Endo-TLIF group was significantly less than those in the MIS-TLIF group within 2 weeks after surgery [weighted mean difference (WMD)=-1.33 (-1.98, -0.68), P <0.0001] and at 3 months postoperatively [WMD=-0.72(-0.85, -0.59), P <0.00001]. The Endo-TLIF group also seemed to fewer VAS of back at the last follow-up (≥12 mo) [WMD=-0.12 (-0.25, -0.00), P =0.05]. Compared with the MIS-TLIF group, the Endo-TLIF group was associated with longer operation time [WMD=26.74 (2.14, 51.34), P =0.03], but shorter length of hospital stay [WMD=-1.98(-2.91, -1.05), P <0.0001].

CONCLUSIONS

Compared with minimally invasive TLIF, endoscopic TLIF achieved comparable improvement of symptoms and intervertebral fusion, longer operation time, and smaller surgical trauma. Endoscopic TLIF, which requires a demanding learning curve, maybe a feasible and effective technique for the patients with symptomatic lumbar degenerative diseases.

How I do it: dual operation channels percutaneous endoscopic far-lateral transforaminal lumbar interbody fusion

BACKGROUND

The current surgical procedure of interbody fusion in the lumbar spine has several limitations including low efficiency, potential endplate damage, overdose radiation exposure, and failure of fusion.

METHODS

Through the endoscopic operating channel, we efficiently removed the superior and inferior articular processes and decompressed the ligamentum flavum. Another operating channel was established under endoscopic monitoring to excise the annulus fibrosus, remove the cartilaginous endplate using open instruments, perform interbody bone grafting, and place a non-expandable polyetheretherketone open surgical fusion cage.

CONCLUSION

Lumbar interbody fusion was performed successfully using a far-lateral transforaminal approach combined with dual operation channels of percutaneous endoscopic-assisted technique.

The novel Kambin Torpedo full-endoscopic lumbar interbody fusion technique: a case series

PURPOSE

Full-endoscopic lumbar interbody fusion (FELIF) is a new-generation treatment for spondylolisthesis. However, owing to their unique characteristics, the two main endoscopic fusion trajectories, the trans-Kambin and posterolateral approaches, have important limitations. Herein, we aimed to introduce a new technique called Kambin Torpedo FELIF (KT-FELIF).

METHODS

The KT-FELIF technique is based on the trans-Kambin approach. It additionally completes ipsilateral total facetectomy and contralateral direct decompression. Thus, this novel technique combines the advantages of the trans-Kambin and posterolateral approaches.

RESULTS

We reported on the indications and technical steps of KT-FELIF and provided intraoperative and animated videos to clarify the procedure. Short-term follow-up based on 3-month postoperative computed tomography and plain films images taken at least 3 months after surgery showed adequate bony decompression, a large bone graft contact area, and good intervertebral trabecular bone growth without radiolucent lines between the graft, cage, and end plate. The clinical results, such as ipsilateral and contralateral visual analog scale and Oswestry disability index values, gradually improved at 1 and 3 months postoperatively. No complications were observed.

CONCLUSIONS

KT-FELIF is a promising FELIF technique for achieving bilateral direct decompression through a unilateral approach while accomplishing thorough discectomy and endplate preparation.

Comparison of clinical outcomes and complications between endoscopic and minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative diseases: a systematic review and meta-analysis

OBJECTIVE

This study compares the efficacy and complications of endoscopic transforaminal lumbar fusion (Endo-TLIF) and minimally invasive transforaminal lumbar fusion (MIS-TLIF) in treating lumbar degenerative diseases. It aims to provide reference data for clinical decision-making.

METHODS

We identified randomized controlled studies and non-randomized controlled studies on Endo-TLIF and MIS-TLIF for treating lumbar degenerative diseases based on specific inclusion and exclusion criteria. Data were managed with Endnote X9 software and meta-analyzed using Revman 5.3 software. Extracted outcomes included lower back VAS score, lower extremity pain VAS score, low back pain ODI score, complication rate, fusion rate, time to surgery, blood loss, and length of hospital stay.

RESULTS

① Thirteen high-quality studies were included in this meta-analysis, totaling 1015 patients-493 in the Endo-TLIF group and 522 in the MIS-TLIF group. ② Meta-analysis results revealed no significant differences in preoperative, postoperative 6-month, and final follow-up waist VAS scores, lower limb pain VAS score, ODI index, complications, and fusion rate between the two groups (P > 0.05). The MIS-TLIF group had a shorter operative time (MD = 29.13, 95% CI 10.86, 47.39, P = 0.002) than the Endo-TLIF group. However, the Endo-TLIF group had less blood loss (MD = - 76.75, 95% CI - 111.59, - 41.90, P < 0.0001), a shorter hospital stay (MD = - 2.15, 95% CI - 2.95, - 1.34, P < 0.00001), and lower lumbar VAS scores both immediately postoperative (≤ 2 week) (MD = - 1.12, 95% CI - 1.53, - 0.71, P < 0.00001) compared to the MIS-TLIF group.

CONCLUSION

Meta-analysis results indicated that Endo-TLIF is similar to MIS-TLIF in terms of long-term clinical outcomes, fusion rates, and complication rates. Although MIS-TLIF has a shorter operation time, Endo-TLIF can significantly reduce blood loss and hospital stay duration. Endo-TLIF offers the advantages of less surgical trauma, reduced blood loss, faster recovery, and early alleviation of postoperative back pain.

A novel mini-open transforaminal lumbar interbody fusion for lumbar degenerative diseases: technical note and preliminary results

BACKGROUND

Transforaminal lumbar interbody fusion (TLIF) is an effective and popular surgical procedure for the management of various spinal pathologies, especially degenerative diseases. Surgeons have been pursuing minimally invasive technology as soon as TLIF was appeared. Currently, TLIF can be performed with transforaminal approaches by open surgery, minimally invasive surgery or percutaneous endoscope. We provide a detailed description of a new modified open TLIF with percutaneous pedicle screws, which we refer to as mini-open TLIF. The objective of this study was to present feasibility of this procedure and the preliminary results.

METHODS

The study is a prospective study. From January 2021 to March 2022, 96 patients (43 males and 53 females) with neurological symptoms due to degenerative lumbar spine diseases were enrolled. Operation time, blood loss, ambulatory time, hematocrit and complications were recorded during perioperative period. Clinical symptoms were evaluated 1 week, 3 months and 12 months after surgery. Visual analogue scale (VAS) scores for lower back pain and leg pain and Oswestry disability index (ODI) were assessed. Magnetic resonance imaging was performed preoperatively and 12 months postoperatively to emulate cross-sectional area of paraspinal muscles. The lumbar interbody fusion rate was evaluated by CT scanning.

RESULTS

The mean operation time of single level was 112.6 min, and the mean operation time of multilevel was 140.1 min. Intraoperative blood loss of single level was 64.5 ml and was 116.3 ml of multilevel. The VAS and ODI scores before and after surgery were significantly different (P < 0.0001) and reached minimal clinically important difference. Atrophy rate of paraspinal muscles was 2.5% for symptomatic side and 1.2% for asymptomatic side. The cross-sectional area before and after the operation and atrophy rate had no statistically significant difference (P > 0.05).

CONCLUSION

Mini-open TLIF is effective and feasible for the treatment of lumbar degenerative diseases especially in multilevel disease, with minor damage to muscle and shorter operation time.

TRIAL REGISTRATION

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of the Second Affiliated Hospital of Soochow University (No. JD-LK2023045-I01).

Transforaminal Interbody Fusion Using the Unilateral Biportal Endoscopic Technique Compared With Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Spine Diseases: Analysis of Clinical and Radiological Outcomes

BACKGROUND

There has been a widespread application of minimally invasive spinal surgery techniques in the past few years. Unilateral biportal endoscopic has been successfully used in a variety of lumbar spine diseases, but there are few studies on lumbar fusion assisted by unilateral biportal endoscopy.

OBJECTIVE

To compare the clinical and radiological outcomes of transforaminal interbody fusion using the unilateral biportal endoscopic technique (UBEIF) and transforaminal lumbar interbody fusion (TLIF) in patients with lumbar disease.

METHODS

We studied 128 patients, 58 in the UBEIF group and 70 in the TLIF group. The Oswestry disability index, creatine kinase, visual analog score (VAS) for leg and back pain were used to assess clinical outcomes. Radiographic outcomes were assessed using the fusion rate, internal fixation loosening, and adjacent segment degeneration.

RESULTS

Back and leg pain VAS scores in both groups were significantly lower 3, 6, and 12 months after surgery ( P < .05). A significant reduction in Oswestry disability index in both groups was observed 6 and 12 months after surgery ( P < .05). Compared with the TLIF group at 1 week after surgery, UBEIF patients' VAS score for back pain significantly improved ( P < .05). There was no difference in fusion rate between the 2 groups (98.27% vs 98.57%).

CONCLUSION

UBEIF and TLIF have similar clinical and radiographic outcomes in the treatment of single-segment lumbar disease with lumbar instability, including improved back and leg pain, improved disability, and high fusion rates. Furthermore, with UBEIF, less blood is lost, there is better relief of early back pain, and hospital stays are shorter.

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.

Safety and clinical efficacy of endoscopic procedures for the treatment of adjacent segmental disease after lumbar fusion: A systematic review and meta-analysis

BACKGROUND

Adjacent segment disease (ASD) is a common complication after lumbar fusion and is still traditionally treated by open surgery. In recent years, with the development of minimally invasive techniques, percutaneous endoscopic surgery(PES) has been used for the treatment of ASD after lumbar fusion due to its unique benefits. Nevertheless, it remains unclear about its significant clinical efficacy and advantages over conventional open surgery.

OBJECTIVES

To evaluate the clinical efficacy and safety of PES in the treatment of ASD after lumbar fusion.

STUDY DESIGN

A systematic review and meta-analysis studies about the role of PES in managing ASD after lumbar fusion.

METHODS

A systematic search review was conducted in PubMed, EMBASE, Cochrane Library, Web of Science, CNKI, VIP, WanFang, and SinoMed databases from the start of their construction to 15 November 2021. Eligible studies included references to clinical trials of PES for ASD after open lumbar fusion. Observations included pain relief, recovery of postoperative function, overall excellent rates, and indicators of the advantages of minimally invasive surgery compared to conventional surgery. Postoperative complications and recurrence rates were also recorded.

RESULTS

A total of 24 studies, including 20 single-arm studies and 4 clinical control studies, all involving 928 patients were included. A total of 694 patients were included in the single-arm analysis. The results of the single-arm meta-analysis showed that PES could significantly reduce low back and leg pain and improve the functional status of the lumbar spine in patients with ASD after open lumbar fusion compared to preoperatively, and had good clinical efficacy after surgery. A total of 234 patients were included in the four clinically controlled studies, and the results of the meta-analysis showed that PES could clearly reduce pain and improve lumbar function, with no significant difference in efficacy between PES and open surgery. However, PES has a lower surgical incision, less intraoperative bleeding, and shorter operative time and length of hospital stay compared to open surgery. Moreover, it has a lower rate of postoperative recurrence as well as complications and a longer duration of efficacy.

CONCLUSIONS

On the basis of the available clinical literature and the results of this study, PES could achieve satisfactory clinical effects in ASD treatment after lumbar fusion. Compared with conventional open surgery, PES can not only obtain similar clinical results, but also had the advantages of less trauma and faster recovery. Nevertheless, a randomized controlled study is still needed to validate the findings of this study.

TRIAL REGISTRATION

Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022298387.

Unilateral biportal endoscopic extreme transforaminal lumbar interbody fusion with large cage combined with endoscopic unilateral pedicle screw fixation for lumbar degenerative diseases: a technical note and preliminary effects

OBJECTIVE

The purpose of the study was to investigate the feasibility and preliminary effects of unilateral biportal endoscopic extreme transforaminal lumbar interbody fusion(UBE-eXTLIF) with large cage combined with endoscopic unilateral pedicle screw fixation for lumbar degenerative diseases.

METHODS

Patients with lumbar degenerative diseases who received UBE-eXTLIF with large cage combined with endoscopic unilateral pedicle screw fixation from June 2022 to July 2022 were retrospectively analyzed, including 4 females and 1 males. The clinical symptoms and signs were consistent with the imaging changes. We recorded operation time, length of postoperative hospital stay, and complications. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and modified Macnab scale was used to evaluate the clinical efficacy at preoperative, postoperative 1 month, and the last follow-up.

RESULTS

The operation was successfully completed in all cases. The operation time was 150-180 min, with an average of 164.60 ± 12.03 min. No serious complications such as dural tears and vascular and nerve injuries occurred during operation. All the patients got out of bed 1-3 days after surgery and were hospitalized 4-5 days after surgery, with an average of 4.20 ± 0.45 days. Preoperative VAS scores of low back pain were 6.20 ± 0.84 and respectively decreased to 2.20 ± 0.45 and 1.40 ± 0.55 at postoperative 1 month and at the last follow-up, and the difference was statistically significant (P < 0.05). Preoperative VAS scores of lower limb pain were 4.60 ± 2.61 and respectively decreased to 1.00 ± 0.71 and 0.60 ± 0.55 at postoperative 1 month and at the last follow-up, and the difference was statistically significant (P < 0.05). Preoperative ODI scores were 62.00 ± 3.16 and respectively decreased to 38.00 ± 1.41 and 32.40 ± 3.29 at postoperative 1 month and at the last follow-up, and the difference was statistically significant (P < 0.05). According to the modified Macnab criteria, the final outcome was excellent in 4 cases and good in 1 case. Five patients could return to normal activities within 3 weeks.

CONCLUSIONS

UBE-eXTLIF with large cage combined with endoscopic unilateral pedicle screw fixation can achieve excellent clinical results and may become a new minimally invasive endoscopic fusion method for lumbar degenerative diseases.

Comparison of the Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion and Endoscopic Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Diseases: A Retrospective Matched Case-Control Study

OBJECTIVE

We compared the clinical outcomes of minimally invasive transforaminal lumbar interbody fusion (Mis-TLIF) and endoscopic transforaminal lumbar interbody fusion (Endo-TLIF).

METHODS

We retrospectively analyzed the clinical data of patients who underwent single-segment Mis-TLIF or Endo-TLIF between June 2016 and June 2019 at our hospital. The patients in each treatment group were matched 1:1 for sex, age, and type of lumbar degenerative disease, and their clinical outcomes were compared at discharge and at 1 and 2 years postoperatively.

RESULTS

Our study included 64 patients, with 32 patients in each treatment group. Operative time and fluoroscopy time were significantly higher in the Endo-TLIF versus Mis-TLIF groups, whereas estimated blood loss, postoperative drainage volume, and the low back pain visual analog scale score at discharge were significantly lower. Both treatments achieved exact interbody fusion at the final-follow up. There was no significant difference in the visual analog scale score or Oswestry Disability Index between the groups at 1 and 2 years postoperatively. Complication rates were higher in the Endo-TLIF group (21.9%) than in the Mis-TLIF group (6.2%), although the difference was not significant.

CONCLUSIONS

Although there was no difference in the long-term outcomes between the treatments, Endo-TLIF had less blood loss and a lower postoperative drainage volume and low back pain visual analog scale score at discharge than Mis-TLIF. However, the longer operative time and potentially higher complication rate of Endo-TLIF suggest that surgeons may need to overcome the steeper learning curve than the procedure of Mis-TLIF.

Current Status and research hotspots in the field of full endoscopic spine surgery: A bibliometric analysis

Purpose

We aimed to comprehensively analyze the current status, hotspots, and trends in full endoscopic spine surgery (FESS) research using bibliometric analysis and knowledge domain mapping.

Methods

The Web of Science database was used to screen FESS-related articles published between January 1, 1993 and June 10, 2022. The evaluation involved the following criteria: total number of articles; H-index; and contributions from countries/regions, institutions, journals, and authors.

Results

A total of 1,064 articles were included. Since 2016, there have been a significant number of publications in the field of FESS. The country/region contributing the largest number of articles was China (37.8%), followed by South Korea (24%), the United States (16.1%), Japan (5.7%), and Germany (5.1%). South Korea (35) had the highest H-index, followed by the United States (27), China (22), Japan (21), and Germany (20). World Neurosurgery (15.7%) published the largest number of FESS-related articles. However, among the top 10 most cited articles, six were published in Spine. The author who contributed the most was S.H. Lee (5.4%), and the largest number of contributions in this field originated from Wooridul Spine Hospital (South Korea; 6.1%). Notably, six of the 10 most published authors in this field were from South Korea. Of the top five productive institutions, three were from South Korea. The keywords with the strongest citation bursts in the field of FESS were “lumbar spine,” “discectomy,” “interlaminar,” “surgical technique,” “follow-up,” “excision,” “thoracic spine,” and “endoscopic surgery.” The 10 clusters generated in this study were: “endoscopic discectomy” (#0), “thoracic myelopathy” (#1), “recurrent lumbar disc herniation” (#2), “low back pain” (#3), “cervical vertebrae” (#4), “lumbar spinal stenosis” (#5), “transforaminal lumbar interbody fusion” (#6), “radiation exposure” (#7), “management” (#8), and “lumbar spine” (#9).

Conclusion

Global research on FESS is mostly concentrated in a few countries/regions and authors. South Korea has made the largest contribution to the field of FESS. Based on the most cited keyword bursts and clusters, the focus of FESS research was found to include its indications, management, and applications.

Full-Endoscopic versus Minimally Invasive Lumbar Interbody Fusion for Lumbar Degenerative Diseases : A Systematic Review and Meta-Analysis

Objective

Although full-endoscopic lumbar interbody fusion (Endo-LIF) has been tried as the latest alternative technique to minimally invasive transforaminal lumbar interobody fusion (MIS-TLIF) since mid-2010, the evidence is still lacking. We compared the clinical outcome and safety of Endo-LIF to MIS-TLIF for lumbar degenerative disease.

Methods

We systematically searched electronic databases, including PubMed, EMBASE, and Cochrane Library to find literature comparing Endo-LIF to MIS-TLIF. The results retrieved were last updated on December 11, 2020. The perioperative outcome included the operation time, blood loss, complication, and hospital stay. The clinical outcomes included Visual analog scale (VAS) of low back pain and leg pain and Oswestry disability index (ODI), and the radiological outcome included pseudoarthosis rate with 12-month minimum follow-up.

Results

Four retrospective observational studies and one prospective observational study comprising 423 patients (183 Endo-LIF and 241 MIS-TLIF) were included, and the pooled data analysis revealed low heterogeneity between studies in our review. Baseline characteristics including age and sex were not different between the two groups. Operation time was significantly longer in Endo-LIF (mean difference [MD], 23.220 minutes; 95% confidence interval [CI], 10.669–35.771; p=0.001). However, Endo-LIF resulted in less perioperative blood loss (MD, -144.710 mL; 95% CI, 247.941–41.478; p=0.023). Although VAS back pain at final (MD, -0.120; p=0.586), leg pain within 2 weeks (MD, 0.005; p=0.293), VAS leg pain at final (MD, 0.099; p=0.099), ODI at final (MD, 0.141; p=0.093) were not different, VAS back pain within 2 weeks was more favorable in the Endo-LIF (MD, -1.538; 95% CI, -2.044 to -1.032; p<0.001). On the other hand, no statistically significant group difference in complication rate (relative risk [RR], 0.709; p=0.774), hospital stay (MD, -2.399; p=0.151), and pseudoarthrosis rate (RR, 1.284; p=0.736) were found.

Conclusion

Relative to MIS-TLIF, immediate outcomes were favorable in Endo-LIF in terms of blood loss and immediate VAS back pain, although complication rate, mid-term clinical outcomes, and fusion rate were not different. However, the challenges for Endo-LIF include longer operation time which means a difficult learning curve and limited surgical indication which means patient selection bias. Larger-scale, well-designed study with long-term follow-up and randomized controlled trials are needed to confirm and update the results of this systematic review.

[Analysis of technical advantages and disadvantages of percutaneous endoscopic lumbar interbody fusion and its trend prospect]

OBJECTIVE

To review and evaluate the technical advantages and disadvantages and research progress of percutaneous endoscopic lumbar interbody fusion.

METHODS

The domestic and foreign related research literature on percutaneous endoscopic lumbar interbody fusion was extensively consulted. The advantages, disadvantages, and effectiveness were summarized. And the development trend of this technology was prospected.

RESULTS

Compared with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), percutaneous endoscopic lumbar interbody fusion has less intraoperative and postoperative bleeding, better improvement of low back pain in the early stage after operation, and similar long-term effectiveness, fusion rate, and incidence of complication, but a longer learning curve. The operation time of biportal and large-channel uniportal endoscopic lumbar fusion is close to that of MIS-TLIF, but the operation time of small-channel uniportal endoscopic fusion is longer than that of MIS-TLIF.

CONCLUSION

Percutaneous endoscopic lumbar interbody fusion has the advantages of less trauma and good effectiveness, but its learning curve is long, and indications should be strictly selected for this operation. In the future, with the continuous development and complementation of various endoscopic fusion technologies, this technology will gain better application prospects.

Endoscopic Extreme Transforaminal Lumbar Interbody Fusion With Large Spacers: A Technical Note and Preliminary Report

This report describes a novel endoscopic fusion technique performed with unilateral biportal endoscopy (UBE) that is known as extreme transforaminal lumbar interbody fusion (eXTLIF) and is performed with a large spacer. We also present the short-term results of this procedure. Previous studies reported that minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) could achieve acceptable rates of fusion; therefore, it is often used for treating various degenerative lumbar diseases. Moreover, MIS-TLIF can be performed with a unilateral approach; hence, it is commonly performed with the UBE technique. The biportal endoscopic TLIF procedure is usually performed with a single spacer in the interbody space. It is important to insert the maximum amount of graft material into the preparation site via an autologous bone marrow transplant or any other suitable substance with spacer insertion. Because MIS-TLIF with UBE is performed in water, it might provide an inadequate environment for excellent fusion. Therefore, a modified method was used to increase the surface contact area and insert the maximum amount of bone material with a larger spacer. However, the use of a large spacer necessitates a larger spacer orifice. For this purpose, eXTLIF was performed, which inserts the spacer more laterally compared with the current TLIF position. We report the surgical method and short-term results, which have been satisfactory thus far. [Orthopedics. 2022;45(3):163-168.].

Percutaneous Bilateral Endoscopic Lumbar Interbody Fusion: Technical Note and Preliminary Results

Objective

The purpose of this study was to investigate the feasibility and clinical efficacy of the percutaneous bilateral endoscopy technique (microendoscopic trans-Kambin's triangle lumbar interbody fusion + percutaneous endoscopic transforaminal decompression of the lumbar spinal canal, ME-TKT-LIF+ PETD) in the treatment of lumbar degenerative diseases.

Methods

From May 2016 to September 2018, 29 patients (16 males and 13 females) who suffered from neurologic symptoms due to degenerative lumbar spine disease and underwent percutaneous bilateral endoscopy technique were enrolled. A microendoscope was used for fusion, and a percutaneous endoscope was used for spinal canal decompression. These patients' perioperative and clinical outcome-related parameters were collected and analyzed.

Results

The mean intraoperative blood loss was 72.8 ± 40.6 ml, the operation time was 87.1 ± 10.1 min, the postoperative ambulatory time was 1.69 ± 1.0 days, the hospital stay was 2.6 ± 1.3 days, and the follow-up period was 22.34 ± 4.2 months. The visual analog scale (VAS) and the Oswestry disability index (ODI) were significantly improved at the early postoperative and last follow-up, respectively. According to the modified MacNab criteria, 11 (11/29) cases were rated as excellent, 15 (15/29) as good, and 3 (3/29) as fair, and the excellent and good rate was 89.7%. Twenty-eight (28/29) cases demonstrated solid fusion, and the fusion rate was 96.6%.

Conclusion

The percutaneous bilateral endoscopy technique is safe and feasible in the treatment of lumbar degenerative diseases, with the advantage that more normal anatomical structures are preserved. It is an optional method of lumbar interbody fusion.

Comparison of percutaneous endoscopic and open posterior lumbar interbody fusion for the treatment of single-segmental lumbar degenerative diseases

Background

Endoscopic lumbar interbody fusion has become an emerging technique. Some researchers have reported the technique of percutaneous endoscopic transforaminal lumbar interbody fusion. We propose percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) as an alternative approach. The purpose of this study was to assess the clinical efficacy of PE-PLIF by comparing percutaneous endoscopic and open posterior lumbar interbody fusion (PLIF).

Methods

Thirty patients were enrolled in each group. Demographic data, perioperative data, and radiological parameters were collected prospectively. The clinical outcomes were evaluated by visual analog scale (VAS) and Oswestry Disability Index (ODI) scores.

Results

The background data were comparable between the two groups. The mean operation time was longer in the PE-PLIF group. The PE-PLIF group showed benefits in less blood loss and shorter hospital stay. VAS and ODI scores significantly improved in both groups. However, the VAS score of low-back pain was lower in the PE-PLIF group. The satisfaction rate was 96.7% in both groups. The radiological outcomes were similar in both groups. In the PE-PLIF group, the fusion rate was 93.3%, and the cage subsidence rate was 6.7%; in the open PLIF group, the fusion and cage subsidence rates were 96.7% and 16.7%. There were minor complications in one patient in the PE-PLIF group and two in the open PLIF group.

Conclusions

The current study revealed that PE-PLIF is safe and effective compared with open PLIF. In addition, this minimally invasive technique may enhance postoperative recovery by reducing tissue damage and blood loss.

[Comparative study on effectiveness of percutaneous endoscopic and Wiltse-approach transforaminal lumbar interbody fusion in the treatment of lumbar spondylolisthesis]

OBJECTIVE

To compare the effectiveness of percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) and Wiltse-approach TLIF (W-TLIF) in the treatment of lumbar spondylolisthesis.

METHODS

The clinical data of 47 patients with lumbar spondylolisthesis who met the selection criteria between July 2018 and June 2019 were retrospectively analyzed, in which 21 patients were treated with PE-TLIF (PE-TLIF group) and 26 patients were treated with W-TLIF (W-TLIF group). There was no significant difference between the two groups in age, gender, disease duration, level of spondylolisthesis vertebrae, spondylolisthesis degree, spondylolisthesis type, and preoperative visual analogue scale (VAS) score of low back pain and leg pain, lumbar Japanese Orthopaedic Association (JOA) score, and the disc height (DH), segmental lordosis (SL), and Taillard index (TI) of the operated vertebrae ( P>0.05). The operation time, intraoperative blood loss, postoperative drainage, postoperative bedridden time, and complications were compared between the two groups. The VAS score and JOA score were used to evaluate the improvement of pain and function. At last follow-up, DH, SL, and TI of operated vertebrae were measured by X-ray films, and lumbar CT was performed to evaluate the interbody fusion.

RESULTS

Compared with W-TLIF group, the operation time in PE-TLIF group was significantly longer, but the intraoperative blood loss and postoperative drainage were significantly less, and the postoperative bedridden time was significantly shorter ( P<0.05). There were 2 cases of transient lower limb radiating pain in PE-TLIF group and 1 case of superficial incision infection in W-TLIF group. There was no significant difference in the incidence of complications (9.5% vs. 3.8%) between the two groups ( χ ²=0.037, P=0.848). The patients in both groups were followed up 12-24 months, with an average of 17.3 months in PE-TLIF group and 17.7 months in W-TLIF group. The VAS scores of low back pain and leg pain, and the JOA scores of the two groups significantly improved at each time point after operation when compared with those before operation ( P<0.05). Compared with W-TLIF group, the VAS scores of low back pain in PE-TLIF group significantly lower at 3 days and 3 months after operation ( P<0.05), and the JOA score of PE-TLIF group was significantly higher at 3 months after operation ( P<0.05), and there was no significant difference in each score at any other time point between the two groups ( P>0.05). At last follow-up, the DH, SL, and TI of operated vertebrae of the two groups significantly improved when compared with those before operation ( P<0.05), and there was no significant difference in the differences of each parameter between the two groups ( P>0.05). According to Suk's standard, the fusion rates of PE-TLIF group and W-TLIF group were 90.5% (19/21) and 92.3% (24/26), respectively, with no significant difference ( χ ²=0.000, P=1.000). At last follow-up, there was no case of Cage sunk into the adjacent vertebral body, or dislodgement of Cage anteriorly or posteriorly in both groups.

CONCLUSION

PE-TLIF and W-TLIF are both effective in the treatment of grade Ⅰ and Ⅱ lumbar spondylolisthesis. Although the operation time is prolonged, PE-TLIF has less intraoperative blood loss and postoperative drainage, shorter postoperative bedridden time, and can get more obvious short-term improvement of low back pain and function.

Enhanced Recovery after an Innovative Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Spinal Stenosis: A Prospective Observational Study

Background

The objective of this study was to investigate the enhanced recovery clinical effects of an innovative percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) for the treatment of patients with LSS and degenerative instability.

Methods

From January 2019 to March 2020, 51 patients with single-segment LSS and degenerative instability were prospectively included in our study (ChiCTR1900020679). The Oswestry Disability Index (ODI), the visual analogue scale (VAS) on lumbar and leg pain (VAS-LBP and VAS-LP), serum creatine kinase (CK), the peak intensity of sulphur hexafluoride microbubble contrast agent (PI), and the maximal cross-sectional area of multifidus muscle (Max-CSA) around the surgical incision were assessed preoperatively, postoperatively, and at regular follow-up.

Results

All patients were followed up. The mean postoperative bedridden time was 20.45 ± 2.66 hours. The ODI, VAS-LBP, and VAS-LP were improved significantly after operation compared to these data before operation in all the patients (P < 0.05). The CK at 1 day after operation was higher compared to the data before the operation (P < 0.05), and there was no significant difference on CK at 1 week after operation (P > 0.05). The PI at 1 week after operation was higher compared to this item before operation (P < 0.05), and there was no significant difference on PI at 1 month or 3 months after operation (P > 0.05). The Max-CSA at 1 week after operation was higher compared to this item before the operation (P < 0.05), and there was no significant difference in Max-CSA at 1 month or 3 months after operation compared with before the operation (P > 0.05).

Conclusions

Our results and systematic review presented the innovative PE-TLIF technique could obtain satisfactory and effective outcomes for the treatment of patients with LSS and degenerative instability. Our PE-TLIF technique also had the ability to decrease the MF injury and obtain an enhanced recovery.

Endo-TLIF versus MIS-TLIF in 1-segment lumbar spondylolisthesis: A prospective randomized pilot study

OBJECTIVE

To evaluate the curative efficacy by comparing perioperative characteristics and 1.5-year observational outcomes in 1-segment lumbar spondylolisthesis between traditional minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and optimized Endoscopic TLIF techniques.

METHODS

The study was a single-center, randomized controlled trial comparing two different treatment approaches for 1-segment lumbar spondylolisthesis. 102 patients treated by MIS-TLIF (48 cases) or Endo-TLIF (54 cases) were included from March 2018 to April 2019. Perioperative parameters and clinical outcomes were evaluated. Degree of slip were measured, and fusion rates were determined at 18 months after surgery.

RESULTS

The Endo-TLIF group had similar return to work time and rate. Blood loss, left bed time, analgesic ratio were significantly less in Endo-TLIF group. The Endo-TLIF group had a significantly longer operative time. Significant postoperative reduction in %slip was showed in both groups. The VAS and ODI improved significantly in both groups after surgery. Significant decreases in low-back pain in Endo-TLIF group were found at postoperative day 1 and 3 months. The fusion rate in the two groups was similar.

CONCLUSION

Endo-TLIF surgery with a C-shaped working tube and a visualization system may be regarded as an efficient alternative surgery for 1-segment lumbar spondylolisthesis. It is a safe and minimally invasive way to perform this surgery and has shown satisfactory clinical outcomes.

TRIAL REGISTRATION

ChiCTR1800015197, 13 March 2018.

TRIAL REGISTRY

Chinese Clinical Trial Registry. Registered 13 March 2018. http://www.chictr.org.cn/showproj.aspx?proj=25865.

Lumbar degenerative disease treated by percutaneous endoscopic transforaminal lumbar interbody fusion or minimally invasive surgery-transforaminal lumbar interbody fusion: a case-matched comparative study

Purpose

This study aimed to evaluate the clinical efficacy and imaging results of percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF) through comparing it with minimally invasive surgery-transforaminal lumbar interbody fusion (MISTLIF).

Materials and methods

We performed a retrospective analysis on patients with lumbar degenerative disease treated by PETLIF or MISTLIF from September 2017 to January 2019, and the patients were divided into two groups: the PETLIF group and the MISTLIF group. The clinical and imaging parameters of the two groups were evaluated.

Results

There was no significant difference between the two groups in complication rate. The operative time in the PETLIF group was significantly less than that in the MISTLIF group. Compared with those before operation, the postoperative VAS-L and VAS-B scores were significantly improved after operation in the both groups. In addition, the postoperative VAS-B score of the PETLIF group was significantly lower than that of the MISTLIF group. At the last follow-up, there was no significant difference between the two groups in the VAS-L score, VAS-B score, ODI score, and bony fusion rate.

Conclusions

Both PETLIF and MISTLIF could achieve satisfactory clinical outcomes in the treatment of lumbar degenerative disease, but our study suggested that PETLIF had less damage, rapid recovery after operation, and short discharge time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02841-4.

Full-Endoscopic Trans-Kambin Triangle Lumbar Interbody Fusion: Surgical Technique and Nomenclature

BACKGROUND

 Full-endoscopic lumbar surgery is used for decompression of lumbar spinal canal stenosis. Now, a cage can be inserted through Kambin's triangle for lumbar interbody fusion (LIF). We have been performing full-endoscopic trans-Kambin triangle LIF (KLIF) at our institution since 2018. In this article, we describe this technique and present our results.

METHODS

 We performed full-endoscopic one-level KLIF in 10 patients. The procedure is as follows. First, percutaneous pedicle screws are inserted. Listhesis is reduced if necessary. The endoscope is inserted in Kambin's triangle. Next, the superior articular process is partially removed, enlarging Kambin's triangle to allow safe insertion of the cage. A cannula is inserted into the disk to avoid damaging the exiting nerve. The disk material is shaved and curetted. Finally, the harvested bone is packed in a cage and inserted into the disk space. We analyze the complications, visual analog scores (VAS), and MacNab's criteria.

RESULTS

 One patient had an irritation in the exiting nerve at L4-L5. The VAS for back pain and leg pain decreased from 69 to 9 and from 60 to 9, respectively. The clinical outcome was considered excellent in eight and good in two patients.

CONCLUSIONS

 Kambin's triangle lies immediately behind the psoas major. Therefore, we consider KLIF as a lateral LIF procedure comparable with oblique or extreme LIF. However, unlike oblique or extreme LIF, there are no major vessels and organs in the surgical field; therefore, KLIF is the safest type of lateral LIF. Furthermore, using the endoscope, we can perform decompression directly using the facetectomy technique.

A Modified Endoscopic Transforaminal Lumbar Interbody Fusion Technique: Preliminary Clinical Results of 96 Cases

Background: As a newly emerging technique, endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) has become an increasingly popular procedure of interest. The purpose of this study was to introduce a modified Endo-TLIF system and share our preliminary clinical experiences and outcomes in treating lumbar degenerative disease with this procedure.

Methods: Ninety-six patients (thirty-seven men and fifty-nine women; mean age 55.85 ± 11.03 years) with lumbar degenerative diseases who underwent Endo-TLIF in our hospital were enrolled. The surgical time, volume of intraoperative blood loss, postoperative hospitalization time and postoperative drainage were documented. Clinical outcomes were evaluated by visual analog scale (VAS) scores, Oswestry Disability Index (ODI) scores, and modified MacNab criteria. Bone fusion was identified through computerized tomography (CT) scans or X-ray during the follow-up period.

Results: All patients were followed up for at least 12 months, and the average follow-up time was 17.03 ± 3.27 months. The mean operative time was 136.79 ± 30.14 minutes, and the mean intraoperative blood loss was 53.06 ± 28.89 ml. The mean VAS scores of low back pain and leg pain were 5.05 ± 1.37 and 6.25 ± 1.03, respectively, before surgery, which improved to 2.27 ± 0.66 and 2.22 ± 0.55, respectively, after the operation (P < 0.05). The final VAS scores of low back pain and leg pain were 0.66 ± 0.60 and 0.73 ± 0.66, respectively (P < 0.05). The preoperative ODI score (49.06 ± 6.66) also improved significantly at the 3-month follow-up (13.00 ± 7.37; P < 0.05). The final ODI score was 8.03 ± 6.13 (P < 0.05). There were 10 cases of non-fusion (nine women and one man) at the 12-month follow-up, but no cases of non-union were identified by imaging at the final follow-up.

Conclusions: The present study demonstrated satisfactory clinical and radiologic results among patients who received Endo-TLIF treatment from our institution. This indicates that Endo-TLIF is efficient and safe for select patients.

"Pin Method" for Endoscopic Lumbar Interbody Fusion

BACKGROUND

 Endoscopic lumbar interbody fusion using a cage can have a similar fusion rate as minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) or open lumbar interbody fusion. Direct visual control during cage insertion is the key to prevent neural structure incarceration in endoscopic lumbar interbody fusion. Creating a track with any kind of retractor or cannula for cage insertion under fluoroscopic guidance is not safe enough, because the retractor and cannula can create many blind spots and can displace during cage insertion.

METHOD

 The pin method utilizes two flexible metallic guide pins inserted from the skin incision through the annulotomy site into the disk space until the anterior longitudinal ligament is reached under direct endoscopic monitoring. The two guide pins could be oriented parallel or perpendicular or even reduce to one or increase to many as needed to serve as a sliding track and a see-through barrier to prevent neural incarceration.

RESULTS AND CONCLUSION

 Two cases of L4/L5 grade 2 spondylolisthesis with neurogenic claudication were treated with endoscopic lumbar interbody fusion with 1-year follow-up, and the visual analog scale (VAS) score, Oswestry Disability Index (ODI) score, EuroQol five-dimensional questionnaire (EQ-5D, %) score, and modified Macnab score all improved greatly in both. The author developed an original, cheap, accessible, and safe method called the "pin method," which can be used in both full-endoscopic and biportal surgery and can apply to various approaches and has no limitation on the size and shape of the cage.

Full-Endoscopic Oblique Lateral Lumbar Interbody Fusion: A Technical Note With 1-Year Follow-Up

BACKGROUND

Oblique lateral lumbar interbody fusion (OLLIF) is a minimally invasive lumbar interbody fusion procedure using a bullet-shaped polyetheretherketone (PEEK) nonexpandable fusion cage modified to diminish risk to the exiting nerve root during posterolateral implantation through the Kambin safe zone under fluoroscopic guidance. The objective of this study was to present feasibility of this procedure and 1-year clinical outcome data.

METHODS

The authors present a prospective cohort study of 20 patients who underwent fluoroscopy-guided and full-endoscopic OLLIF in 22 segments allowing protection of the exiting nerve root from January 2018 to March 2019. The foraminoplasty, discectomy, endplate preparation, placement of bone graft and insertion of the fusion cage was done under continuous full-endoscopic visualization. The OLLIF fusion was backed up with bilateral percutaneous posterior supplemental pedicle screw fixation. Primary clinical outcome measures were the visual analog scale (VAS) of low back and leg pain, and Oswestry disability index (ODI) at 1 week, 3 months, 6 months, and 1 year after the operation. At final follow-up, the Macnab score was also evaluated. Secondary outcome measures were computed tomography (CT) assessment fusion using the Mannion classification of spinal fusion and adverse events related to the device as well as magnetic resonance imaging (MRI) assessment of nerve root decompression.

RESULTS

All patients had significant relief of low back pain and leg pain, by VAS and ODI scores that improved significantly (P < .01). There were no complications. Postoperative lumbar MRI of all patients showed sufficient direct nerve decompression. At 1-year follow-up, excellent Macnab outcomes were obtained 13 patients, good in six, and fair in one. Impaired sensation and muscle strength of the involved nerve root significantly recovered in all but 2 patients (P < .05). According to the Mannion CT-based classification of spinal fusion, CT showed complete interbody fusion achieved in all 22 segments.

CONCLUSIONS

Full-endoscopic OLLIF is a safe, effective, minimally invasive, economical, practical, and widely applicable minimally invasive interbody fusion technique in the lumbar spine.

LEVEL OF EVIDENCE

3.

Zina percutaneous screw fixation combined with endoscopic lumbar intervertebral fusion under intraoperative neuromonitoring: A case report

INTRODUCTION

Traditional open discectomy and intervertebral fusion surgery is the common strategy for lumbar disc herniation (LDH). However, it has the disadvantages of long recovery time and severe paravertebral soft tissue injury. Zina percutaneous screw fixation combined with endoscopic lumbar intervertebral fusion (ZELIF), as a novel minimally invasive surgical technique for LDH, has the advantages in quicker recovery, less soft tissue destruction, shorter hospital stays and less pain. We report a novel technique of ZELIF under intraoperative neuromonitoring (INM) for the treatment of LDH.

PATIENT CONCERNS

A 51-year-old male presented to our hospital with left lower extremity pain and numbness for 1 year.

DIAGNOSIS

Lumbar disc herniation (LDH).

INTERVENTIONS

This patient was treated with Zina percutaneous screw fixation combined with endoscopic neural decompression, endplate preparation, and intervertebral fusion through Kambin's triangle. Each step of the operation was performed under INM.

OUTCOMES

The follow-up period lasted 12 months; the hospitalization lasted 4 nights; the blood loss volume was 65 ml, and the time of operation was 266 min. INM showed no neurological damage during the surgery. No surgical complications, including neurological deterioration, cage migration, non-union, instrumentation failure or revision operation, were observed during the follow-up period. Visual Analogue Scale (VAS) score reduced from 7 to 1; the Oswestry Disability Index (ODI) decreased from 43 to 14; the EQ-5D score was 10 preoperatively and 15 at the final follow-up visit; the Physical Component Summary of the 36-Item Short Form Health Survey (SF-36) was 48 preoperatively and 49 at the last follow up visit; the SF-36 Mental Component Summary was 47 before surgery and decreased to 41 postoperatively.

CONCLUSION

ZELIF under INM may represent a feasible, safe and effective alternative to endoscopic intervertebral fusion and percutaneous screw fixation, for decompressing the lumbar's exiting nerve root directly with minimal invasion in selected patients.

Microendoscopy-assisted extraforaminal lumbar interbody fusion for treating single-level spondylodesis

Background

Lumbar interbody fusion is a standard technique for treating degenerative lumbar disorders involving instability. Due to its invasiveness, a minimally invasive technique, extraforaminal lumbar interbody fusion (ELIF), was introduced. On surgically approaching posterolaterally, the posterior muscles and spinal canal are barely invaded. Despite its theoretical advantage, ELIF is technically demanding and has not been popularised. Therefore, we developed a microendoscopy-assisted ELIF (mELIF) technique which was designed to be safe and less invasive. Here, we aimed to report on the surgical technique and clinical results.

Methods

Using a posterolateral approach similar to that of lateral disc herniation surgery, a tubular retractor, 16 or 18 mm in diameter, was placed at the lateral aspect of the facet joint. The facet joint was partially excised, and the disc space was cleaned. A cage and local bone graft were inserted into the disc space. All disc-related procedures were performed under microendoscopy. The spinal canal was not invaded. Bilateral percutaneous screw-rod constructs were inserted and fixed.

Results

Fifty-five patients underwent the procedure. The Oswestry Disability Index and visual analogue scale scores greatly improved. Over 90% of the patients obtained excellent or good results based on Macnab’s criteria. There were neither major adverse clinical effects nor the need for additional surgery.

Conclusions

mELIF is minimally invasive because the spinal canal and posterior muscles are barely invaded. It produces good clinical results with fewer complications. This technique can be applied in most single-level spondylodesis cases, including those involving L5/S1 disorders.

Minimally invasive spine surgery: evaluation of clinical and functional outcomes and their correlation with the return to work

BACKGROUND

Intervertebral disc changes are a multi-factorial problem whose main clinical feature is pain. Studies show that when clinical treatments fail, the proposed surgical treatments frequently present unsatisfactory results. Traditional lumbar arthrodesis causes important clinical and functional changes that can result in complications and jeopardize the patients' quality of life.

OBJECTIVES

This study aims to investigate the clinical and functional results of minimally invasive spine surgery in patients with a clinical diagnosis of low-back or sciatic pain and segmental instability, finally correlating these results with the patients' return to work.

METHODS

Patients signed an informed consent form and were clinical and radiographically re-evaluated by independent professionals in the pre- and postoperative periods. Evaluation methods used the Oswestry disability index, as well as visual analog scale and Medical Outcomes Short Form Health Survey (SF-36) scores. We also retrieved epidemiological data, information on work resumption, and bone consolidation evaluations from the medical records.

RESULTS

We evaluated 19 patients who had been operated on 33 levels; visual analog scale and Oswestry disability index scores were initially reduced from 10% to 2% and from 64% to 28%, respectively. SF-36 scores were significantly higher in 5 of the 7 questionnaire scales at the end of the follow-up period. Most patients (68.4%) did not return to work after surgery; the others returned 2 to 67 months after the procedure. All patients received social security benefits after the surgery.

CONCLUSION

Although the procedure presented positive results, it did not result in a satisfactory return-to-work rate. Our results should be analyzed in view of the low educational level and income of the patients, the manual nature of their labor, and the validity of social security benefits.

Methods and Early Clinical Results of Percutaneous Lumbar Interbody Fusion

OBJECTIVE

Percutaneous lumbar interbody fusion (PELIF) is a procedure that includes the use of new devices, which allow minimally invasive diskectomy under the percutaneous full-endoscopic guidance and safe percutaneous insertion of a standard-sized cage. This procedure can be applied to severe disk degeneration, spondylolisthesis, and all lumbar intervertebral levels including the L5-S1 level. We report the methods and the clinical outcomes of this procedure.

METHODS

Percutaneous diskectomy was performed with an outer sheath cutter and other devices. A cage was inserted with an L-shaped retract-slider. Hybrid facet screw fixation was performed for severe disk degeneration without spondylolisthesis. Conventional percutaneous pedicle screw fixation was performed for spondylolisthesis. The subjects consisted of 21 patients, who underwent PELIF and were followed up for 1 year or longer.

RESULTS

No complications related to cage insertion were detected. The mean visual analogue scale scores were improved from 6.1 to 1.9 for lower back pain in severe disc degeneration cases without spondylolisthesis, and from 7.6 to 1.0 for lower extremity symptoms in spondylolisthesis cases.

CONCLUSION

The clinical outcomes were favorable. PELIF was found to be a minimally invasive method that did not compromise safety and efficiency. PELIF is a possible therapeutic option that should be considered for not only spondylolisthesis at various intervertebral levels but also for severe disk degeneration because of its minimal invasiveness.

Radiographic anatomy and clinical significance of percutaneous endoscopic transforaminal oblique fixation from posterior corner in lumbar spine

Background

Endoscopic transforaminal decompression and interbody fusion (ETDIF) has been widely discussed due to its advantages of less trauma, less bleeding, quick recovery, high safety, and relatively fewer complications, as well as adverse factors such as incomplete decompression, steep learning curve, low fusion rate, and high radiation risk. Furthermore, this technique requires the use of supplemental posterior pedicle-screw. Decompression, interbody fusion and percutaneous pedicle screw implantation are not completed in a single channel. Percutaneous endoscopic transforaminal oblique fixation from posterior corner in lumbar spine (PETOFPC) overcomes the above limitations. The purpose of this study is to confirm the anatomical feasibility for PETOFPC in the posterolateral transforaminal approach and to provide anatomic data for the design of new integrated fixable and fused interbody cage.

Methods

Sixty volunteers (22 men and 38 women) who underwent lumbar CT scans were collected and sent to the GEAW4.4 workstation. As a cohort study, the distances and angles of each path in the sagittal and axial planes were measured and analyzed statistically.

Results

The lengths of each path are not less than 40mm, and the longest can be up to 46mm. The paths in full-length group are about 5mm longer than that in medium group. PE (from point P to target E) path was the optimal path. The angles of each path were significantly different (P≤0.001), namely, a1 > a2 > a3, b1 > b2 > b3, and c1 < c2 < c3.

Conclusions

This study confirms anatomic feasibility for PETOFPC and provides anatomic data for the design of new integrated fixable and fused interbody cage. PETOFPC may be a very promising technology and have great clinical significance.

Uniportal Endoscopic Lumbar Interbody Fusion

The cause of radiculopathy is the compression of the nerve root which can be secondary to sliding of the vertebra and reduced disc height. In some patients, decompression alone does not resolve this problem. We describe the uniportal endoscopic transforaminal lumbar interbody fusion technique. Full-endocopic foraminotomy and discectomy are followed by cage implementation and percutaneous instrumentation. The goal of this surgical method is decompression of nerve roots, segment stabilization, disc height, and sagittal alignment restoration. Uniportal endoscopic facet sparing transforaminal transkambin lumbar interbody fusion is a good surgical option to treat degenerative disc disease, mechanical instability, and spondylolisthesis. This method shows favourable clinical outcomes in selected patients.

Minimally invasive surgery for low-grade spondylolisthesis: percutaneous endoscopic or oblique lumbar interbody fusion

Aim: To compare the clinical and radiographic outcomes of percutaneous endoscopic-assisted lumbar interbody fusion (PELIF) versus oblique lumbar interbody fusion (OLIF) for the treatment of symptomatic low-grade lumbar spondylolisthesis. Material & methods: The clinical and radiographic records of 48 patients underwent single-level minimally invasive lumbar fusion with a PELIF (n = 16) or OLIF (n = 32) were reviewed. Results: The clinical and radiographic outcomes were similar in both groups. PELIF procedure exhibited superior capability of the enlargement of foraminal width, but inferior capability of the restoration of foraminal height than OLIF procedure. Conclusion: PELIF minimizes the iatrogenic damages and perioperative risks to a great extent, and seems to be a promising option for the treatment of symptomatic low-grade lumbar spondylolisthesis.

Full-Endoscopic Removal of Lumbar Juxtafacet Cysts: A Prospective Multicentric Study

BACKGROUND

Lumbar juxtafacet cysts are benign lesions that grow at the level of facet joints or within neighboring structures. Recently, there is an ongoing trend toward less invasive procedures for treating degenerative spine diseases. Here we report a multicenter study of full-endoscopic surgery for juxtafacet cyst removal.

METHODS

We prospectively collected patients with a diagnosis of lumbar juxtafacet cyst surgically treated in 3 institutions between January 2017 and August 2019. Patients of any sex and age were eligible if they had a single level unilateral lumbar juxtafacet cyst, invalidating radicular pain lasting >6 weeks, adequate imaging, and failed percutaneous or conservative treatment. Age at diagnosis; sex; preoperative, postoperative, and 6-month leg pain; surgical and medical complications; spine instability (preoperatively and at 6 and 12 months); and follow-up time were collected.

RESULTS

Thirty-five patients were enrolled. Median operative time was 78 minutes, and mean leg pain went from a preoperative value of 6.8 (standard deviation [SD] = 1.2) to a postoperative value of 3.4 (SD = 1.1, P < 0.001) to 2.1 (SD = 1.7, P < 0.001) at 6 months. At a median follow-up of 15 months, approximately 89% of patients were pain-free or improved. We had 2 recurrences of radicular pain, treated conservatively. Only 2 surgical complications (6%) occurred: 2 small dural tears, both resolved without further intervention.

CONCLUSIONS

Full-endoscopic surgery is feasible and safe for juxtafacet cyst removal. Our results are consistent with findings from recent full-endoscopic and series, with outcomes overlapping those reported for open or tubular techniques.

Worldwide research productivity in the field of full-endoscopic spine surgery: a bibliometric study

PURPOSE

To investigate the quantity and quality of articles in the field of full-endoscopic spine surgery (FESS) from different countries and assess characteristics of worldwide research productivity.

METHODS

Articles published from 1997 to July 23, 2018, were screened using the Web of Science database. All studies were assessed for the following parameters: the number of total publications, h-index, contribution of countries, authors, journals, and institutions.

RESULTS

A total of 408 articles were identified between 1997 and 2018. Between 1997 and 2017, the number of published articles tended to increase by 41 times. The largest number of articles was from China (30.15%), followed by South Korea (28.68%), the USA (13.97%), Germany (9.31%), and Japan (4.90%). The highest h-index was found for articles from South Korea (23), followed by the USA (18), Germany (16), China (11), and Japan (7). The highest number of articles was published in World Neurosurgery (12.50%), followed by Pain Physician (10.29%), Spine (6.62%), European Spine Journal (4.66%), and Journal of Neurosurgery: Spine (4.17%). Wooridul Spine Hospital published the largest number of articles (10.29%), followed by Tongji University (5.88%), University of Witten/Herdecke (5.39%), Brown University (5.15%), and Third Military Medical University (3.43%).

CONCLUSIONS

The number of articles published in the field of FESS has increased rapidly in the past 20 years. In terms of quantity, China is the most contributive country based on the number of publications. High-quality papers as measured by h-index and the large quantity is from South Korea (second only to China). These slides can be retrieved under Electronic Supplementary Material.

Endoscopic transforaminal lumbar interbody fusion: a comprehensive review

INTRODUCTION

Endoscopic spine surgery has been developed as a minimally invasive technique for decompression in patients with lumbar disc herniation or lumbar stenosis. Recent reports have described the use of endoscopic technology in lumbar fusion surgeries, especially for transforaminal lumbar interbody fusion (TLIF). This review aimed to summarize the current techniques of endoscopic TLIF and to discuss the benefits, limitations, and future perspectives of endoscopic lumbar fusion surgery.

AREAS COVERED

This review covered the English-language medical literature published in Medline and focused specifically on endoscopic technologies incorporated into minimally invasive TLIF. The endoscopic TLIF techniques are categorized here according to the properties of the endoscope: percutaneous endoscopic TLIF, biportal endoscopic TLIF, and microendoscopic TLIF. Even though most authors have reported favorable clinical and radiological outcomes of endoscopic TLIF, such evidence originates mainly from case series.

EXPERT OPINION

Although the current level of evidence is low and the technical relevance of the technique is controversial, the key concept and early results of endoscopic TLIF are promising. Technical advancements to improve safety and reduce technical complexity, as well as comparative cohort studies and randomized clinical trials with long-term follow-up are required to promote the adoption of endoscopic TLIF in clinical practice.

A Pilot Study of Percutaneous Interlaminar Endoscopic Lumbar Sequestrectomy: A Modern Strategy to Tackle Medically-Refractory Radiculopathies and Restore Spinal Function

Objective

Angled scopes allow 360° visualization, which makes percutaneous endoscopic techniques (percutaneous endoscopic lumbar discectomy, PELD) particularly attractive for sequestrectomies, which entail the removal of extruded lumbar disc fragments that have migrated caudally or cranially between the ligaments, foramina, and neural structures, while preserving the disc. Although many different PELD techniques are currently available, not all of them are suitable for sequestrectomies; furthermore, long-term follow-up data are unfortunately lacking.

Methods

A pilot study was conducted on a cohort of 270 patients with lumbar radiculopathy undergoing minimally invasive spine surgery (PELD or microdiscectomy), of whom only 7 were eligible for endoscopic interlaminar sequestrectomy with disc preservation. The patients’ baseline conditions and clinical outcomes were measured with the Oswestry Disability Index and a visual analogue scale. Long-term follow-up was conducted using satisfaction questionnaires that were based on the MacNab criteria and administered by medical/nursing personnel not involved in their primary surgical management.

Results

EasyGo system was eventually used in 5 PELD cases. No dural tears, infections, or nerve root injuries were recorded in patients undergoing sequestrectomy. Surgical events, including blood loss and overall length of hospital stay, did not differ significantly among the 270 patients. In the group treated with endoscopic sequestrectomy, no recurrences or complications were noted during a follow-up of 3 years, and an excellent degree of satisfaction was reported.

Conclusion

We provide OCEBM (Oxford Centre for Evidence-Based Medicine) level 3 evidence that interlaminar endoscopic sequestrectomy is a tailored and well-tolerated surgical option; nonetheless, a cost-effectiveness analysis assessing the interval until return to working activities and long-term benefits is warranted.

Clinical results of percutaneous biportal endoscopic lumbar interbody fusion with application of enhanced recovery after surgery

OBJECTIVE

The aims of enhanced recovery after surgery (ERAS) are to improve surgical outcomes, shorten hospital stays, and reduce complications. The objective of this study was to introduce ERAS with biportal endoscopic transforaminal lumbar interbody fusion (TLIF) and to investigate the clinical results.

METHODS

Patients were divided into two groups based on the fusion procedures. Patients who received microscopic TLIF without ERAS were classified as the non-ERAS group, whereas those who received percutaneous biportal endoscopic TLIF with ERAS were classified as the ERAS group. The mean Oswestry Disability Index (ODI) and visual analog scale (VAS) scores were compared between the two groups. In addition, demographic characteristics, diagnosis, mean operative time, estimated blood loss (EBL), fusion rate, readmissions, and complications were investigated and compared.

RESULTS

Forty-six patients were grouped into the non-ERAS group (microscopic TLIF without ERAS) and 23 patients into the ERAS group (biportal endoscopic TLIF with ERAS). The VAS score for preoperative back pain on days 1 and 2 was significantly higher in the non-ERAS group than in the ERAS group (p < 0.05). The mean operative duration was significantly higher in the ERAS group than in the non-ERAS group, while the mean EBL was significantly lower in the ERAS group than in the non-ERAS group (p < 0.05). There was no significant difference in fusion rate between the two groups (p > 0.05). Readmission was required in 2 patients who were from the non-ERAS group. Postoperative complications occurred in 6 cases in the non-ERAS group and in 2 cases in the ERAS group.

CONCLUSIONS

Percutaneous biportal endoscopic TLIF with an ERAS pathway may have good aspects in reducing bleeding and postoperative pain. Endoscopic fusion surgery along with the ERAS concept may help to accelerate recovery after surgery.

CT-based Morphometric Analysis of Approach of Percutaneous Transforaminal Endoscopic Lumbar Interbody Fusion

OBJECTIVES

A radiographic study was designed to measure the relationship of the exiting nerve root and its surroundings to the corresponding intervertebral disc for percutaneous transforaminal endoscopic lumbar interbody fusion to better understand the regional anatomy and to improve clinical applications.

METHODS

A retrospective study from January 2017 to October 2017 was conducted at Tianjin Hospital. CT images were obtained from patients presenting low back pain (110 patients), and analysis was performed bilaterally from L2-3 to L5 S1 . In the rotating coronal plane we analyzed: the nerve root-dural sac distance at the superior and inferior margins of the disc (Js, Ji); the nerve root-pedicle distance at the medial, middle, and lateral borders of the pedicle (Pa, Pb, Pc); the pedicle width (W); and the safe working zone, defined as a trapezoid bounded by the inferior pedicle and the exiting nerve root (S). In the transverse plane, the nerve root-articular process and the shortest distance for the nerve root-articular process joint surface were analyzed at the superior and inferior margins of the disc (Gs, Gi), respectively. The groups were analyzed using ANOVA, and paired t-tests were used to compare the left and right sides.

RESULTS

From L2-3 to L5 S1 , the distance of the nerve root to the dural sac was larger at the inferior margin of the disc. From L2-3 to L5 S1 , each segment of the vertebral nerve root-pedicle distance gradually decreased from medial to lateral. From L2-3 to L5 S1 , the distance from the exiting nerve root to the middle and lateral margins of the pedicle gradually decreased, with L5 S1 being the minimum. Some significant differences were observed between the left and right sides for L4-5 and L5 S1 . The pedicle width of the vertebral body and the mean area for the safe working zone gradually increased from L2-3 to L5 S1 . In the axial plane, the shortest distance between the nerve root and articular process joint surface at the inferior margin of the disc was greater than the distance for the nerve root to the articular process at the superior margin of the disc from L2-3 to L5 S1 . There were no significant differences between the two sides.

CONCLUSIONS

It is more difficult to implant a cage with a width of 10 mm above the L3-4 level. By removing part of the superior articular process, the safe working area can be expanded, and damage to the nerve or other structures can be avoided when implanting a cage.

Percutaneous Endoscopic Lumbar Interbody Fusion: Technical Note and Preliminary Clinical Experience with 2-Year Follow-Up

Objective

Endoscopic surgeries have been attempted in the field of lumbar decompression and fusion surgery in the past decade. Percutaneous endoscopic lumbar interbody fusion (PELIF) is a new-emerging technique taking advantages of an anatomical (Kambin's triangle) to achieve simultaneous decompression and fusion under endoscopic visualization. The purpose of this study is to evaluate the feasibility and safety of PELIF technique with general anesthesia and neuromonitoring.

Methods

The authors present the details of PELIF technique with general anesthesia and neuromonitoring. The first 7 consecutive patients treated with minimum of 2 year's follow-up were included. Clinical outcomes were assessed by visual analog scale (VAS) for back and leg pain, Oswestry Disability Index (ODI) scores, and the Short Form-36 health survey questionnaire (SF-36) in the immediate preoperative period and during the follow-up period.

Results

All patients underwent single-level PELIF surgery successfully and without conversion to open surgery. The average age was 56.0±13.0 years. All patients had Grade I degenerative/isthmic spondylolisthesis and 4 patients coexisted with disc herniation. The mean operative time was 167.5±30.9 minutes, and intraoperative blood loss was 70.0±24.5 ml. Postoperative drainage volume was 24.5±18.3 ml. The differences in the VAS scores for low back pain and leg pain between preoperative and follow-up were significant (P<0.05). The SF-36 Physical Component Summary (PCS) improved from 38.83±4.17 to 55.67±2.58 (P<0.001). The SF-36 Mental Component Summary (MCS) improved from 43.83±3.13 to 57.50±5.36 (P=0.001). The ODI score improvement rate was 33.7±3.7 %. All cases demonstrated radiopaque graft in the intervertebral disc space consistent with solid arthrodesis.

Conclusions

PELIF technique seems to be a promising surgical technique for selected appropriate patients, with the minimal invasive advantages in decreased blood, shortage of ambulation time, and hospital stay, compared with MIS-TLIF. Because of limited Kambin's triangle space and the exiting nerve root nearby, PELIF is still a challenging technique. Future advancement and development in instrument and cage design are vital for application and popularization of this technique. Prospective, randomized, controlled studies with large sample size on PELIF technique are still needed to prove its safety, efficacy, and minimal invasive advantages.