Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion: Technique Note and Comparison of Early Outcomes with Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Spondylolisthesis

How to Prevent Nerve Root Injury in Uniportal Full Endoscopic Lumbar Fusion Surgery? Insights From a Cadaveric Anatomic Study With Simulation Surgery

STUDY DESIGN

The study included 2 fresh-frozen cadavers.

OBJECTIVE

To elucidate the positional relationship between surgical instruments and nerve roots during full endoscopic facet-sparing (FE fs-TLIF) and full endoscopic facet-resecting (FE fr-TLIF) transforaminal lumbar interbody fusion and propose safe instrumentation insertion procedures and recommend cage glider designs aimed at protecting nerve roots.

BACKGROUND

Endoscopic surgical techniques are increasingly used for minimally invasive lumbar fusion surgery, with FE fr-TLIF and FE fs-TLIF being common approaches. However, the risk of nerve root injury remains a significant concern during these procedures.

PATIENTS AND METHODS

Eight experienced endoscopic spine surgeons performed uniportal FE fr-TLIF and FE fs-TLIF on cadaveric lumbar spines, totaling 16 surgeries. Postoperation, soft tissues were removed to assess the positional relationship between the cage entry point and nerve roots. Distances between the cage entry point, traversing nerve root, and exiting nerve root were measured. Safe instrumentation design and insertion procedures were determined.

RESULTS

In FE fr-TLIF, the mean distance between the cage entry point and traversing nerve root was significantly shorter compared with FE fs-TLIF (3.30 ± 1.35 vs . 8.58 ± 2.47 mm, respectively; P < 0.0001). Conversely, the mean distance between the cage entry point and the exiting nerve root was significantly shorter in FE fs-TLIF compared with FE fr-TLIF (3.73 ± 1.97 vs . 6.90 ± 1.36 mm, respectively; P < 0.0001). For FE fr-TLIF, prioritizing the protection of the traversing root using a 2-bevel tip cage glider was crucial. In contrast, for FE fs-TLIF, a single-bevel tip cage glider placed in the caudal location was recommended.

CONCLUSION

This study elucidates the anatomic relationship between cage entry points and nerve roots in uniportal endoscopic lumbar fusion surgery. Protection strategies should prioritize the traversing root in FE fr-TLIF and the exiting root in FE fs-TLIF, with corresponding variations in surgical techniques.

LEVEL OF EVIDENCE

Level V.

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 Fusion Rate and Clinical Outcomes in Minimally Invasive and Conventional Posterior Fusion for Lumbar Degenerative Disease: A Network Meta-Analysis

BACKGROUND

The fusion rate, clinical efficacy, and complications of minimally invasive fusion surgery and open fusion surgery in the treatment of lumbar degenerative disease are still unclear.

METHODS

We conducted a literature search using PubMed, Embase, Cochrane Library, CNKI, and WANFANG databases.

RESULTS

This study included 38 retrospective studies involving 3097 patients. Five intervention modalities were considered: unilateral biportal endoscopic-lumbar interbody fusion (UBE-LIF), percutaneous endoscopic-lumbar interbody fusion (PE-LIF), minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF), transforaminal lumbar interbody fusion (TLIF), and posterior lumbar interbody fusion (PLIF). Quality assessment indicated that each study met acceptable quality standards. PE-LIF demonstrated reduced low back pain (Odds Ratio = 0.50, Confidence Interval: 0.38-0.65) and lower complication rate (Odds Ratio = 0.46, Confidence Interval: 0.25-0.87) compared to PLIF. However, in indirect comparisons, PE-LIF showed the lowest fusion rates, with the ranking as follows: UBE-LIF (83.2%) > MIS-TLIF (59.6%) > TLIF (44.3%) > PLIF (39.8%) > PE-LIF (23.1%). With respect to low back pain relief, PE-LIF yielded the best results, with the order of relief as follows: PE-LIF (96.4%) > MIS-TLIF (64.8%) > UBE-LIF (62.6%) > TLIF (23.0%) > PLIF (3.2%). Global and local consistency tests showed satisfactory results, and heterogeneity tests indicated good stability.

CONCLUSIONS

Compared to conventional open surgery, minimally invasive fusion surgery offered better scores for low back pain and Oswestry Disability Index, lower complication rates, reduced bleeding, and shorter hospital stays. However, minimally invasive fusion surgery did not show a significant advantage in terms of fusion rate and had a longer operative time.

Percutaneous lumbar interbody fusion results in less perioperative opioid usage compared to minimally invasive transforaminal lumbar interbody fusion: a single institution, multi-surgeon retrospective study

Background

Ultra-minimally invasive percutaneous lumbar interbody fusion (percLIF) has been demonstrated to further minimize tissue trauma and has been associated with improved clinical outcomes including decreased blood loss, post-operative pain and length of stay when compared to minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery. A single-institution retrospective study was conducted to investigate whether 1-level percLIF is associated with decreased narcotic consumption compared to 1-level MIS-TLIF in the first 24-hour following surgery.

Methods

A retrospective study of patients undergoing either single-level percLIF or MIS-TLIF from January 2018 to December 2021. Opioid consumption in the 24-hour following surgery was converted into total morphine milligram equivalents (MME). The primary outcome used univariate and multivariate regression analysis to compare MME consumption between the MIS-TLIF and percLIF groups. Secondary outcome variables included, estimated blood loss, total intraoperative MME, MME at discharge, MME at 30 days post-op, exiting nerve root injury, post-anesthesia care unit (PACU) visual analogue scale (VAS) score at handoff, time to first ambulation, distance ambulated post-operative day one and hospital length of stay.

Results

A total of 51 patients (21 percLIF vs. 30 MIS-TLIF) were included in the study. Univariate regression analysis revealed that on average patients who underwent percLIF had a 24-hour postoperative MME -50.8 mg (95% CI: -91.6, -10) lower than those who had MIS-TLIF (P=0.02). On multivariable analysis, after adjusting for sex and age, 24-hour postoperative MME closely failed to meet statistical significance (P=0.06) with an average of -40.8 mg (95% CI: -83.2, 1.6) MME in percLIF patients compared to MIS-TLIF. There was no statistically significant difference in MME between MIS-TLIF and percLIF at the time of discharge and at 30 days post-op.

Conclusions

In the setting of the current opioid epidemic in the United States and increased numbers of patients undergoing lumbar interbody fusion, spine surgeons must continue to do their part helping reduce the need for opioid prescriptions for postoperative pain management. New "ultra-MIS" techniques such as percLIF allow surgeons to further decrease tissue trauma, which should lead to reduced need for post-operative narcotic requirements.

Is endoscopic technique an effective and safe alternative for lumbar interbody fusion? A systematic review and meta-analysis

Study design

Systematic review; meta-analysis.

Purpose

Lumbar degenerative disease is frequent and has a tremendous impact on patients' disability and quality-of-life. Open and minimally invasive procedures have been used to achieve adequate decompression and fusion. Endoscopic lumbar interbody fusion (Endo-LIF) is emerging as an alternative, trying to reduce morbidity, while achieving comparable to superior clinical outcomes. The aim of this work is to perform a systematic review and meta-analysis to investigate how Endo-LIF compares to open or minimally invasive procedures.

Methods

Electronic databases (MEDLINE, Scopus, Web of Science, Cochrane) were systematically reviewed using the query: '(percutaneous OR endoscop*) AND (open OR minimal* invasive) AND lumbar AND fusion'. PRISMA guidelines were followed.

Results

Twenty-seven articles were included (25 cohort study, 1 quasi-experimental study, and 1 randomized control trial; for meta-analytical results, only observational studies were considered). Endo-LIF conditioned longer operative time, with significantly lower blood loss, bedtime, and hospital length of stay. Early post-operative back pain favored endoscopic techniques. Endo-LIF and non-Endo-LIF minimally invasive surgery displayed comparable results for most back and leg pain or disability outcomes, despite Endo-LIF having been associated with higher disability at late follow-up (versus Open-LIF). No differences were found regarding fusion rates, cage subsidence, or adverse events. Definitive conclusions regarding fusion rate cannot be drawn due to low number of studies and unstandardized fusion definition.

Conclusion

Endo-LIF is an effective and safe alternative to conventional lumbar interbody fusion procedures. Evidence shortcomings may be addressed, and future randomized control trials may be performed to compare techniques and to validate results.

Unilateral biportal endoscopic versus microscopic transforaminal lumbar interbody fusion for lumbar degenerative disease: a retrospective study

BACKGROUND

In the past decade, Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with a microscopic tubular technique has become a surgical procedure that reduces surgical-related morbidity, shortens hospital stays, and expedites early rehabilitation in the treatment of lumbar degenerative diseases (LDD). Unilateral biportal endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) has emerged as a novel surgical technique. The present study aims to compare the clinical outcomes and postoperative complications of MIS-TLIF and Endo-TLIF for treating LDD.

METHODS

A retrospective analysis of LLD patients undergoing either Endo-TLIF or MIS-TLIF was performed. Patient demographics, operative data (operation time, estimated blood loss, length of hospitalization), and complications were recorded. The visual analog scale (VAS) score for leg and back pain and the Oswestry Disability Index (ODI) score were used to evaluate the clinical outcomes.

RESULTS

This study involved 80 patients, 56 in the MIS-TLIF group and 34 in the Endo-TLIF group. The Endo-TLIF group showed a more substantial improvement in the VAS for back pain at 3 weeks post-surgery compared to the MIS-TLIF group. However, at the 1-year mark after surgery, there were no significant differences between the groups in the mean VAS for back pain and VAS for leg pain. Interestingly, the ODI at one year demonstrated a significant improvement in the Endo-TLIF group compared to the MIS-TLIF group. Additionally, the MIS-TLIF group exhibited a shorter operative time than the Endo-TLIF group, with no notable differences in estimated blood loss, length of hospitalization, and complications between the two groups.

CONCLUSION

Endo-TLIF and MIS-TLIF are both safe and effective for LDD. In surgical decision-making, clinicians may consider nuances revealed in this study, such as lower early postoperative back pain with Endo-TLIF and shorter operative time with MIS-TLIF.

Xu D. A novel technique for decortication of the lumbar facet joints for posterolateral fusion with percutaneous exposure: A cadaveric feasibility study

Background

Percutaneous approaches to the spine have been explored recently for various procedures, including transforaminal lumbar interbody fusion. It is known that facet decortication leads to higher rates of fusion, but effective percutaneous approaches have not been well documented. There are a set of instruments used in the cervical spine for percutaneous decortication, the CORUS™ Spinal System-X (DI# 00852776006508), which may be useful in this setting. Our aim was to investigate the feasibility of decorticating the lumbar facet joints with these instruments in cadavers to aid in minimally invasive lumbar fusion.

Methods

We performed percutaneous facet joint decortication at each facet joint in the lumbar spine in two adult cadavers. We tested varying degrees of laterality for entry points and angulation for access at each level to optimize the innovative procedure.

Results

When using the CORUS™ Spinal System-X to obtain percutaneous access for facet decortication in the lumbar spine, we successfully dissected down to the facet joint without neurovascular injury. At the L1-L2 and L2-L3 levels, access was best obtained at 4 cm from midline with an angulation of 10°. At the L3-L4 and L4-L5 level, access was best obtained at 4 cm from midline with an angulation of 20°.

Conclusions

This study demonstrates that percutaneous lumbar facet joint decortication is feasible with the CORUS™ Spinal System-X instruments, and warrants further, comparative study in the clinical setting.

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.

Comparison of Outcomes Between Endoscopic Transforaminal Lumbar Interbody Fusion and Minimally Invasive Transforaminal Lumbar Interbody Fusion in Patients With Single-Level Lumbar Degenerative Disease: A Retrospective Study

OBJECTIVE

The objective of this study was to compare the clinical and radiological outcomes of endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

This retrospective study included 110 patients with single-level lumbar degenerative disease who underwent Endo-TLIF or MIS-TLIF between January 2019 and December 2021. Patients were divided into Endo-TLIF (n = 55) and MIS-TLIF groups (n = 55). Perioperative, clinical, and radiological outcomes were assessed.

RESULTS

The Endo-TLIF group had significantly lower blood loss and shorter hospital stay. However, the operation time was significantly longer and there was more x-ray exposure than in the MIS-TLIF group. There were no significant differences in complications between the groups. The Endo-TLIF group showed significantly lower creatine kinase levels than the MIS-TLIF group at 3 days postoperatively (P < 0.05), but not at 7 days postoperatively (P > 0.05). Oswestry Disability Index and visual analog scale scores were significantly reduced in both groups at different time points postoperation compared to preoperation. The visual analog scale score in the Endo-TLIF group was lower than that in the MIS-TLIF group at 3 days postoperatively. Moreover, no significant differences were found in fusion rates, lumbar lordosis, and lumbar segmental lordosis between the 2 groups (P > 0.05).

CONCLUSIONS

Endo-TLIF might be considered as an effective and reliable treatment option for single-level lumbar degeneration. It results in less trauma and faster postoperative recovery, but a longer operative time and more x-ray exposure than MIS-TLIF. Endo-TLIF has effects on clinical and radiological outcomes that are comparable to those of MIS-TLIF.

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.

Stability simulation analysis of targeted puncture in L4/5 intervertebral space for PELD surgery

Introduction: The application prospects of percutaneous endoscopic lumbar discectomy (PELD) as a minimally invasive spinal surgery method in the treatment of lumbar disc herniation are extensive. This study aims to find the optimal entry angle for the trephine at the L4/5 intervertebral space, which causes less lumbar damage and has greater postoperative stability. To achieve this, we conduct a three-dimensional simulated analysis of the degree of damage caused by targeted puncture-based trephine osteotomy on the lumbar spine. Methods: We gathered clinical CT data from patients to construct a lumbar model. This model was used to simulate and analyze the variations in trephine osteotomy volume resulting from targeted punctures at the L4/5 interspace. Furthermore, according to these variations in osteotomy volume, we created Finite Element Analysis (FEA) models specifically for the trephine osteotomy procedure. We then applied mechanical loads to conduct range of motion and von Mises stress analyses on the lumbar motion unit. Results: In percutaneous endoscopic interlaminar discectomy, the smallest osteotomy volume occurred with a 20° entry angle, close to the base of the spinous process. The volume increased at 30° and reached its largest at 40°. In percutaneous transforaminal endoscopic discectomy, the largest osteotomy volume was observed with a 50° entry angle, passing through the facet joints, with smaller volumes at 60° and the smallest at 70°. In FEA, M6 exhibited the most notable biomechanical decline, particularly during posterior extension and right rotation. M2 and M3 showed significant differences primarily in rotation, whereas the differences between M3 and M4 were most evident in posterior extension and right rotation. M5 displayed their highest stress levels primarily in posterior extension, with significant variations observed in right rotation alongside M4. Conclusion: The appropriate selection of entry sites can reduce lumbar damage and increase stability. We suggest employing targeted punctures at a 30° angle for PEID and at a 60° angle for PTED at the L4/5 intervertebral space. Additionally, reducing the degree of facet joint damage is crucial to enhance postoperative stability in lumbar vertebral motion units.

Is Full-Endoscopic Transforaminal Lumbar Interbody Fusion Superior to Open Transforaminal Lumbar Interbody Fusion for Single-Level Degenerative Lumbar Spondylolisthesis? A Retrospective Study

BACKGROUND

 In this study, we evaluate the clinical efficacy and safety of full-endoscopic transforaminal lumbar interbody fusion (TLIF) for treatment of single-level lumbar degenerative spondylolisthesis.

METHODS

 Fifty-three patients were divided into two groups according to the surgical techniques: Full endoscopic (Endo)-TLIF (n = 25) and TLIF (n = 28). Clinical efficacy was evaluated pre- and postoperatively. The operation time, operative blood loss, postoperative amount of serum creatine phosphokinase (CPK), postoperative drainage volume, postoperative hospital stay time, total cost, and operative complications were also recorded.

RESULTS

 Compared with the TLIF group, the Endo-TLIF group had similar intraoperative blood loss, less postoperative increased CPK, less postoperative drainage volume, and shorter postoperative hospital stay, but longer operative time and higher total cost. The postoperative visual analog scale (VAS) scores of back and leg pain and Oswestry Disability Index (ODI) scores significantly improved compared with the preoperative scores in both two groups; more significant improvement of postoperative VAS scores of back pain and ODI scores were shown in the Endo-TLIF group at the 1-month follow-up (p < 0.05). No difference was found in the intervertebral fusion rate between the two groups.

CONCLUSION

 The Endo-TLIF has similar clinical effect compared with the TLIF for the treatment of lumbar degenerative spondylolisthesis. It also has many surgical advantages such as less muscle trauma, less postoperative back pain, and fast functional recovery of the patient. However, steep learning curve, longer operative time, and higher total cost may be the disadvantages that limit this technique. Also, the Endo-TLIF treatment of patients with bilateral lateral recess stenosis is considered a relative contraindication.

Clinical Outcome of Full Endoscopic Trans Kambin's Triangle Lumbar Interbody Fusion: A Systematic Review

Full-endoscopic (FE) lumbar interbody fusion (LIF) is now a widely used type of minimally invasive surgery (MIS). Although FE-LIF includes LIF with foraminoplasty via a Kambin's triangle approach (FE-KLIF) and LIF with foraminotomy via an interlaminar approach, these techniques are rarely discussed separately. This review evaluates the outcomes and complications of FE-KLIF reported in the literature. The PubMed, Medline, Embase, Web of Science, and Cochrane Library databases were searched for studies reporting the outcomes of FE-KLIF. Of 464 publications assessed, 11 met our inclusion criteria. Although the most frequently treated level was L4/5, L5/S1 was also treated. FE-KLIF was performed under local anesthesia and sedation or under epidural anesthesia without general anesthesia. Visual analog scale and Oswestry Disability Index scores were improved postoperatively in all uncontrolled studies; however, there was no significant difference in these scores in studies that compared FE-KLIF with posterior LIF (PLIF) or MIS-transforaminal LIF (TLIF). There was also no significant difference in the fusion rate between FE-KLIF and PLIF or MIS-TLIF. In terms of complications, although there were no reports of hematoma, dural tear and surgical site infection were reported in 1 paper each, with transient nerve disorders reported in 5 studies (frequency, 1.8%-23.5%). This review indicates that FE-KLIF is a feasible and viable surgical option for lumbar degenerative disease. However, the amount and level of evidence is low for the studies included in this review, and the data on long-term outcomes remain limited.

Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion (PETLIF): Current Techniques, Clinical Outcomes, and Narrative Review

Full endoscopic techniques are becoming more popular for degenerative lumbar pathologies. Percutaneous endoscopic lumbar interbody fusion (PETLIF) is a minimally invasive surgical technique for spondylolisthesis and lumbar spinal canal stenosis with instability. Nagahama first introduced PETLIF in 2019. This study investigated the clinical outcomes and complications of 24 patients who underwent PETLIF in our facility and compared them with previous studies. Literature searches were conducted on PubMed and Web of Science. The PETLIF surgical technique involves three steps to acquire disc height under general anesthesia. The procedure includes bone harvesting, spondylolisthesis reduction, endoscopic foraminoplasty, disc height expansion using an oval dilator, and intervertebral disc curettage. A cage filled with autologous bone is inserted into the disc space and secured with posterior fixation. Patients underwent PETLIF with an average operation time of 130.8 min and a blood loss of 24.0 mL. Postoperative hospital stays were 9.5 days. Improvement in VAS, disc height, spinal canal area, and % slip was observed, while lumbar lordosis remained unchanged. Complications included end plate injury, subsidence, and exiting nerve root injury. The differences between PETLIF and the extracted literature were found in patients' age, direct decompression, epidural or local anesthesia, approach, order of PPS, and cage insertion. In conclusion, PETLIF surgery is a practical, minimally invasive surgical technique for patients with lumbar degenerative diseases suffering from back and leg pain, demonstrating significant improvements in pain scores. However, it is essential to carefully consider the potential complications and continue to refine the surgical technique further to enhance the safety and efficacy of this procedure.

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

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is a classic surgical procedure for the treatment of lumbar degenerative diseases (LDD). With the development of endoscopic technology, endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) can also achieve adequate decompression and interbody fusion. However, whether Endo-TLIF is superior to MIS-TLIF has not been adequately studied. In this systematic review and meta-analysis, we aimed to evaluate the treatment difference between Endo-TLIF vs MIS-TLIF.

METHODS

We conducted a systematic review and meta-analysis of the studies to compare the clinical outcomes and complications associated with Endo-TLIF vs. MIS-TLIF for the treatment of LDD. A literature search was conducted using the PubMed, Embase, Cochrane Library and Scopus databases for studies published up to April 1, 2022. Both retrospective and prospective studies that compared between Endo-TLIF and MIS-TLIF were included.

RESULTS

A total of 8 studies involving 581 patients were finally included in this meta-analysis. Endo-TLIF significantly prolonged the operation time, but reduced the blood loss amount and length of hospital stay. Moreover, Endo-TLIF was superior to MIS-TLIF on relief of back pain and functional recovery in the early postoperative period. However, there were no significantly differences in long-term clinical outcomes, fusion rate and incidence of complications between Endo-TLIF and MIS-TLIF.

CONCLUSIONS

Endo-TLIF was similar to MIS-TLIF in the long-term clinical outcomes, fusion and complication rates. Endo-TLIF prolongs the operation time, but shortens the length of hospital stay, and has the advantages of less surgical trauma, less blood loss, faster recovery, and early postoperative back pain relief.

Comparison of minimally invasive transforaminal lumbar interbody fusion and endoscopic lumbar interbody fusion for lumbar degenerative diseases: a retrospective observational study

BACKGROUND

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and endoscopic lumbar interbody fusion (Endo-LIF) are both minimally invasive interbody fusion procedures for lumbar degenerative diseases. In this study, we attempted to compare the clinical efficacy and postoperative outcomes of MIS-TLIF and Endo-LIF for lumbar degenerative diseases.

METHODS

The study cohort comprised 99 patients with lumbar degenerative diseases treated by MIS-TLIF or Endo-LIF from January 2019 to July 2021. The clinical outcomes (visual analogue scale (VAS), Oswestry disability index (ODI), and MacNab criteria) preoperatively, 1 month postoperatively, 3 months postoperatively, and 1 year postoperatively were compared between the two groups.

RESULTS

There were no significant differences between the two groups in sex, age, disease duration, affected spine segment, and complications (P > 0.05). The operation time was significantly longer in the Endo-LIF group than the MIS-TLIF group (155.25 ± 12.57 vs. 123.14 ± 14.50 min; P < 0.05). However, the Endo-LIF group had a significantly smaller blood loss volume (61.79 ± 10.09 vs. 259.97 ± 14.63 ml) and shorter hospital stay (5.46 ± 1.11 vs. 7.06 ± 1.42 days) than the MIS-TLIF group. In both groups, the ODI and VAS scores for lower back pain and leg pain were significantly lower at each postoperative timepoint than preoperatively (P < 0.05). Although there were no significant differences between the two groups in the ODI and VAS scores for lower back pain and leg pain (P > 0.05), the VAS for lower back pain was lower in the Endo-LIF group than the MIS-TLIF group at each postoperative timepoint. The MacNab criteria showed that the improvement rate was 92.2% in the MIS-TLIF group and 91.7% in the Endo-LIF group, with no significant difference between the two groups (P > 0.05).

CONCLUSIONS

There were no significant differences in short-term surgical outcomes between the MIS-TLIF and Endo-LIF groups. Compared with the MIS-TLIF group, the Endo-LIF group incurred less damage to surrounding tissues, experienced less intraoperative blood loss, and had less lower back pain, which is more conducive to recovery.

Percutaneous endoscopic versus minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative diseases: a meta-analysis

Introduction

Transforaminal lumbar interbody fusion (TLIF) is commonly used in patients with lumbar degenerative disease (LDD). The most commonly used techniques include minimally invasive TLIF (MIS-TLIF) and percutaneous endoscopic TLIF (PE-TLIF).

Aim

To compare the safety and clinical effectiveness of PE-TLIF and MIS-TLIF in treating LDD.

Material and methods

We screened for related articles in multiple scientific databases, namely, PubMed, Embase, Cochrane Library, Wanfang, VIP, and CINK, and analyzed the relative outcomes.

Results

Based on our inclusion criteria, we selected 8 studies for meta-analysis. There are a total of 229 patients who underwent PE-TLIF and 258 patients who underwent MIS-TLIF. MIS-TLIF and PE-TLIF have similar effectiveness in relieving leg pain and improving the Oswestry Disability Index. However, PE-TLIF is superior in relieving back pain. The pooled data of fusion rates, postoperative analgesic, and complication rates are comparable between the 2 groups. The pooled operation and intra-operative fluoroscopic time are both significantly higher in the PE-TLIF group than the MIS-TLIF group. The pooled intra-operative blood loss, incision length, duration from surgery to ambulation, and hospital stay are significantly lower in the PE-TLIF group than the MIS-TLIF group. Most of the endpoints reveal significant heterogeneity. The endpoints of operation time and intra-operative blood loss reveal significant publication bias.

Conclusions

Both PE-TLIF and MIS-TLIF are safe and effective interventions for patients with LDD. When compared, although MIS-TLIF results in reduced operative time, less intra-operative blood loss and enhanced post-operative recovery can be achieved by PE-TLIF.

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.

Fully Endoscopic 360° Decompression for Central Lumbar Spinal Stenosis Combined with Disc Herniation: Technical Note and Preliminary Outcomes of 39 Cases

Purpose

To evaluate the outcomes, feasibility, and safety of endoscopic unilateral laminectomy, bilateral decompression and discectomy (Endo-ULBDD) for central lumbar spinal stenosis (CLSS) combined with disc herniation (DH).

Methods

This study includes 39 patients diagnosed with CLSS combined with DH who met the inclusion criteria and underwent surgery for Endo-ULBDD from April 2020 to March 2021. The mean age of the patients, operation time, hospitalization time, time in bed, and complications were recorded. Patients were followed up for at least 12 months. Visual analog scale (VAS) scores for low-back and lower-limb pain and Oswestry Disability Index (ODI) scores were evaluated preoperatively, before discharge, and at 3, 6, and 12 months postoperatively. To evaluate clinical effectiveness 12 months postoperatively, the modified MacNab criteria were used.

Results

The mean age of the patients was 59.9 years, the mean operation time was 82.1 minutes, the mean hospitalization time was 3.7 days, and the mean time in bed was 20.9 hours. The mean VAS scores of low-back and lower-limb pain improved from 5.9 and 7.2 to 2.0 and 1.6, respectively (P < 0.05). The ODI score improved from 56.0 to 16.7 (P < 0.05). The overall excellent-good rate of the modified MacNab criteria was 89.7%. Two kinds of complications occurred in 4 patients (10.3%), including 1 patient whose inferior articular process was excessively removed and 3 patients who suffered from postoperative dysesthesia. No other severe complications were noted.

Conclusion

Endo-ULBDD is a safe, feasible, efficient, and minimally invasive approach to treating CLSS combined with DH.

Full-Endoscopic Lumbar Interbody Fusion Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion with a Tubular Retractor System: A Retrospective Controlled Study

OBJECTIVE

The objective of this study was to compare the safety and clinical efficacy of full-endoscopic lumbar interbody fusion (FE-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

A total of 70 patients with single-level lumbar degenerative diseases underwent FE-LIF or MIS-TLIF with a tubular retractor system from August 2018 to August 2020. Postoperatively, the efficacy and safety were compared using several clinical and radiological indices.

RESULTS

A total of 32 patients underwent FE-LIF and 38 received MIS-TLIF with a tubular retractor system, and all patients had no apparent complications. The FE-LIF group had higher radiation exposure, longer operation time, and less bleeding than the MIS-TLIF group (P < 0.05). Postoperative lumbar magnetic resonance imaging showed that the nerve decompression was sufficient. The pain in the lower back and legs was significantly relieved, and the Oswestry Disability Index (ODI) score was greatly improved after surgery (P < 0.01) in both the groups. The sensory and motor functions of nerve roots were remarkably recovered in both the groups at the 1-year follow-up (P < 0.05), and there was no significant difference in MacNab scores between the 2 groups. As per Mannion's fusion classification, the interbody fusion rate was significantly better in the FE-LIF group than in the MIS-TLIF group.

CONCLUSIONS

FE-LIF, which is safe, effective, and minimally invasive, exhibits the same clinical efficacy as MIS-TLIF but with longer operation time and increased radiation exposure.

Risk factors for hidden blood loss in unilateral biportal endoscopic lumbar spine surgery

Background

Unilateral biportal endoscopic (UBE) spine surgery is a minimally invasive procedure for treating lumbar disorders. Hidden blood loss (HBL) is easily ignored by surgeons because blood loss is less visible. However, there are limited studies on HBL in UBE spine surgery. This study aimed to evaluate HBL and its possible risk factors in patients undergoing UBE spine surgery.

Methods

Patients with lumbar disc herniation or lumbar spinal stenosis who underwent unilateral biportal endoscopic surgery between December 2020 and February 2022 at our hospital were retrospectively analyzed. Patient demographics, blood loss-related parameters, and surgical and radiological information were also collected. Pearson or Spearman correlation analysis was conducted to determine the association between clinical characteristics and HBL. Multivariate linear regression analysis was used to determine the independent risk factors for HBL.

Results

Fifty-two patients (17 males and 35 females) were retrospectively enrolled in this study. The mean total blood loss (TBL) volume was 434 ± 212 ml, and the mean HBL volume was 361 ± 217 ml, accounting for 77.9% of the TBL in patients who underwent UBE surgery. Multivariate linear regression analysis revealed that HBL was positively associated with operation time (P = 0.040) and paraspinal muscle thickness at the target level (P = 0.033).

Conclusions

The amount of HBL in patients undergoing UBE surgery should not be neglected. Operation time and paraspinal muscle thickness at the target level may be independent risk factors for HBL.

Application of electromagnetic navigation in endoscopic transforaminal lumbar interbody fusion: a cohort study

STUDY DESIGN

Clinical retrospective cohort study.

OBJECTIVES

To explore the application of the electromagnetic navigation system in Endo-TLIF.

MATERIALS AND METHODS

From May 2019 to March 2020, 76 patients with single-segment lumbar spondylolisthesis treated by electromagnetic navigation-assisted Endo-TLIF (NE group) and conventional Endo-TLIF (CE group) were enrolled in the study. Time of pedicle screw implantation, entire operation time, the number of intraoperative X-ray fluoroscopy exposures, total blood loss, incision length, ambulation time, accuracy of pedicle screws, complications, visual analog scale for back and leg pain, Oswestry Disability Index, Japanese Orthopedic Association score and postoperative fusion rates were recorded, respectively.

RESULTS

There were no significant differences in preoperative demographics between the NE and CE groups (P > 0.05). The mean number of intraoperative X-ray fluoroscopy exposures, guidewires insertion, entire operation time, total blood loss and adjustment rate of screws in the NE group were significantly less compared with the CE group (P < 0.05, respectively). There were no significant differences in clinical parameters between the two groups at different time points in the follow-up period (P > 0.05). There was no statistical difference in fusion rates between the two groups. In addition, one case of cage subsidence was observed after surgery in the CE group.

CONCLUSION

Electromagnetic navigation systems could be applied throughout the entire surgical course and ameliorate the shortcomings of the conventional Endo-TLIF technique to reduce radiation exposure, improve accuracy, avoid repetitive operations and shorten surgery time and the required learning curve of the procedure.

LEVEL OF EVIDENCE I

Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Comparison of hidden blood loss and clinical efficacy of percutaneous endoscopic transforaminal lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion

Purpose

Hidden blood loss (HBL) is a growing area of interest for spinal surgeons. Simultaneously, spine surgeons’ pursuit of minimally invasive spine surgery has never ceased, as evidenced by the increasing number of articles comparing percutaneous endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) and minimally invasive transforaminal lumbar interbody fusion (Mis-TLIF). However, there has been no comparison of HBL between Endo-TLIF and Mis-TLIF. This study aimed to compare HBL, visible blood loss (VBL), and total blood loss (TBL) following Endo-TLIF and Mis-TLIF and evaluate the clinical significance of these procedures.

Methods

Between October 2017 and October 2019, 370 patients underwent lumbar interbody fusion at our institution and were followed up for at least 24 months. Our study included 41 Endo-TLIF and 43 Mis-TLIF cases. We recorded each patient’s age, height, weight, and haematocrit and calculated the TBL, which was used to indirectly obtain the HBL. Additionally, we compared the clinical outcomes of these two groups, including visual analogue scores for the lumbar spine and leg (VAS-Back; VAS-Leg), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, disease type, operative segment, and intervertebral fusion and complication rates.

Results

Endo-TLIF had significantly lower HBL, VBL, and TBL values than Mis-TLIF (P < 0.05 for all). Although Endo-TLIF contained significantly less HBL than Mis-TLIF, the HBL to TBL ratio was statistically greater in Endo-TLIF (91%) than in Mis-TLIF (87%). Concerning clinical outcomes, VAS-Back, VAS-Leg, ODI, JOA, and Endo-TLIF demonstrated greater improvement rates than Mis-TLIF one week post-operatively. However, at the final follow-up, VAS-Back, VAS-Leg, ODI, and JOA scores all demonstrated a trend toward sustained improvement, with no statistically significant between-procedure difference. There were no statistically significant between-procedure differences in disease type, surgical segment, and complication or fusion rates.

Conclusion

Endo-TLIF significantly reduced HBL, VBL, and TBL compared to Mis-TLIF and improved short-term clinical outcomes; however, long-term clinical outcomes and fusion rates remained comparable between the two groups, as did the incidence of peri-operative complications.

Comparison of Postoperative Outcomes Between Percutaneous Endoscopic Lumbar Interbody Fusion and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Spinal Stenosis

Objective

This study aimed to compare postoperative outcomes in surgical and patient-reported outcomes (PROs) between percutaneous endoscopic lumbar interbody fusion (PE-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of lumbar spinal stenosis (LSS).

Methods

We reviewed a total of 89 patients undergoing single-level surgery for lumbar spinal stenosis from January 2018 to July 2021. The cases were categorized as PE-LIF (Group PE-LIF, 41 cases) or MIS-TLIF (Group MIS-TLIF, 48 cases) approach. Parameters obtained at baseline through at least six months of follow-up were collected. The surgical outcomes involving the operative time, estimated blood loss, postoperative bed staying time, and length of hospital stays were analyzed. PROs included the Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), modified MacNab standard evaluation, intervertebral fusion rate, and postoperative complications.

Results

A total of 89 patients were included in this analysis involving 41 patients who underwent PE-LIF and 48 patients who underwent MIS-TLIF. The 2 groups were similar in gender, age, body mass index, follow-up time and surgery levels (P > 0.05), and were not significantly different in the length of hospital stays (P > 0.05). PE-LIF had a significantly longer operative time, greater fluoroscopy time, lower estimated blood loss and shorter bed rest time than MIS-TLIF. Both groups improved significantly from baseline for the VAS and ODI scores. PE-LIF was associated with a lower VAS score for back pain at three-day after surgery. There were no significant differences between PE-LIF and MIS-TLIF in the excellent or good rates and intervertebral fusion rates at the last follow-up (P > 0.05). As for related complications, there were no significant complications occurred, and no significant differences were seen in the complications between both groups (P > 0.05).

Conclusions

To summarize, PE-LIF and MIS-TLIF are both safe and effective for LSS. PE-LIF has a definite short-term curative effect with less trauma.

Full-Endoscopic Posterior Lumbar Interbody Fusion with Epidural Anesthesia: Technical Note and Initial Clinical Experience with One-Year Follow-Up

Objective

The purpose of this study was to introduce and evaluate the early clinical outcomes of the full-endoscopic posterior lumbar interbody fusion (Endo-PLIF) technique with epidural anesthesia (EA) for single-segment lumbar degenerative diseases.

Methods

In this retrospective case series study, we explored the feasibility and effectiveness of the Endo-PLIF with EA for single-segment lumbar degenerative diseases. Between March 2018 and January 2019, a series of 24 patients with single-segment lumbar degenerative diseases underwent Endo-PLIF surgery and were followed up for a minimum of 12 months (15.21±2.27 months). Clinical outcomes including visual analog scale (VAS) scores for back and leg pain, Oswestry Disability Index (ODI) scores, and the Short Form-36 health survey questionnaire (SF-36) were evaluated preoperatively, and postoperatively at 3 days and at 3, 6, and 12-months.

Results

All patients underwent successful single-segment Endo-PLIF surgery. The mean operation time was 209.17±39.49 min, and average amount of bleeding was 43.33±14.87 mL. The VAS for lower extremity pain and back pain significantly improved at 3 days, and at 3, 6, 12 months compared with preoperative, respectively. The ODI scores decreased from 42.04±3.96 to 12.75±2.71 (P<0.001) at preoperative and 12 months postoperatively, respectively. The SF-36 Physical Component Scores (PCS) improved from 34.96±4.63 preoperatively to 52.08±6.05 (P<0.001) at 12 months postoperatively. Additionally, the SF-36 Mental Component Scores (MCS) improved from 39.38±5.70 at preoperative to 53.13±5.97 (P<0.001) at 12 months postoperatively. Two patients experienced dysesthesia, and one patient had a wound infection.

Conclusion

Endo-PLIF with EA is a feasible and valuable technique for the treatment of single-segment lumbar degenerative diseases in selected patients.

Endoscopic Lumbar Interbody Fusion and Minimally Invasive Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Degenerative Diseases: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare clinical efficacy and safety of endoscopic lumbar interbody fusion (Endo-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in treatment of lumbar degenerative diseases.

METHODS

A literature search was performed using PubMed, Embase, Web of Science, and Cochrane Library databases. Studies published up to November 15, 2020, that compared Endo-LIF with MIS-TLIF for treating lumbar degenerative diseases were retrieved. Data were extracted according to predefined clinical outcome measures. Primary outcomes were preoperative and postoperative visual analog scale for leg and back pain and Oswestry Disability Index scores. Secondary outcomes were operative time and intraoperative blood loss; length of hospitalization; and complication, reoperation, and fusion rates. Data analysis was conducted with statistical software.

RESULTS

The meta-analysis included 6 studies comprising 480 patients. Results of the merged analysis revealed similar complication, reoperation, and fusion rates and preoperative and postoperative visual analog scale for leg and back pain and Oswestry Disability Index scores (P > 0.05) for Endo-LIF and MIS-TLIF. Nevertheless, with the exception of longer operative time (P < 0.05), Endo-LIF compared favorably with MIS-TLIF, with less intraoperative blood loss, shorter hospital stay (P < 0.05), and better long-term functional outcome.

CONCLUSIONS

Based on the evidence provided by this study, there is no significant difference in clinical efficacy and safety between Endo-LIF and MIS-TLIF in the treatment of lumbar degenerative diseases. Although Endo-LIF has a longer operative time, it has the advantages of less tissue trauma and rapid recovery after operation.