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

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.

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.

Efficacy of PE-PLIF with a novel ULBD approach for lumbar degeneration diseases: a large-channel endoscopic retrospective study

PURPOSE

This study aims to assess the effectiveness of Percutaneous Endoscopic Posterior Lumbar Interbody Fusion (PE-PLIF) combined with a novel Unilateral Laminotomy for Bilateral Decompression (ULBD) approach using a large-channel endoscope in treating Lumbar Degenerative Diseases (LDD).

METHODS

This retrospective analysis evaluates 41 LDD patients treated with PE-PLIF and ULBD from January 2021 to June 2023. A novel ULBD approach, called 'Non-touch Over-Top' technique, was utilized in this study. We compared preoperative and postoperative metrics such as demographic data, Visual Analogue Scale (VAS) for pain, Oswestry Disability Index (ODI), Japanese Orthopedic Association (JOA) score, surgical details, and radiographic changes.

RESULTS

The average follow-up duration was 14.41 ± 2.86 months. Notable improvements were observed postoperatively in VAS scores for back and leg pain (from 5.56 ± 0.20 and 6.95 ± 0.24 to 0.20 ± 0.06 and 0.12 ± 0.05), ODI (from 58.68 ± 0.80% to 8.10 ± 0.49%), and JOA scores (from 9.37 ± 0.37 to 25.07 ± 0.38). Radiographic measurements showed significant improvements in lumbar and segmental lordosis angles, disc height, and spinal canal area. A high fusion rate (97.56% at 6 months, 100% at 12 months) and a low cage subsidence rate (2.44%) were noted.

CONCLUSIONS

PE-PLIF combined with the novel ULBD technique via a large-channel endoscope offers significant short-term benefits for LDD management. The procedure effectively expands spinal canal volume, decompresses nerve structures, improves lumbar alignment, and stabilizes the spine. Notably, it improves patients' quality of life and minimizes complications, highlighting its potential as a promising LDD treatment option.

Biomechanical evaluation of Percutaneous endoscopic posterior lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion: a biomechanical analysis

In order to analyze and evaluate the stability of lumbar spine and the risk of cage subsidence after different minimally invasive fusion operations, two finite element models Percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) and minimally invasive transforaminal lumbar interbody Fusion (MIS-TLIF) were established. The results showed that compared with MIS-TLIF, PE-PLIF had better segmental stability, lower pedicle screw rod system stress, and lower risk of cage subsidence. The results suggest that the cage with appropriate height should be selected to ensure the segmental stability and avoid the risk of the subsidence caused by the cage with large height.

Clinical efficacy of percutaneous endoscopic posterior lumbar interbody fusion and modified posterior lumbar interbody fusion in the treatment of lumbar degenerative disease

BACKGROUND

To compare the early clinical efficacy of percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) and modified posterior lumbar interbody fusion (MPLIF) in the treatment of lumbar degenerative disease (LDD).

METHODS

A total of 37 patients who underwent PE-PLIF and 58 patients who underwent MPLIF from March 2019 to January 2022 were retrospectively reviewed. The operation time, intraoperative blood loss, post-operative hospitalization time, and post-operative bedrest time were recorded. The visual analogue scale (VAS) scores of leg pain and low back pain, Japanese Orthopaedic Association (JOA) scores, and the Oswestry Disability Index (ODI) scores were evaluated and compared before the operation, 3 days after the operation, 1 week after the operation, 1 month after the operation, 6 months after the operation and at the last follow-up. The modified MacNab's criteria were applied at the last follow-up. The fusion rate and surgical-related complications during follow-up were recorded.

RESULTS

The average operation time in the PE-PLIF group was highly significant longer than that in the MPLIF group (P < 0.01). The intraoperative blood loss, post-operative hospitalization time, and post-operative bedrest time were significantly less in the PE-PLIF group than those in the MPLIF group (P < 0.01). There were highly significant differences in VAS scores of leg pain, VAS scores of low back pain, JOA scores, ODI scores at the last follow-up compared with those before the operation in the two groups (P < 0.01). Three days after the operation and 1 week after the operation, the VAS scores for low back pain and ODI were highly significant less in the PE-PLIF group than that in the MPLIF group (P < 0.01). Three days after the operation, the JOA scores were highly significant higher in the PE-PLIF group than that in the MPLIF group (P < 0.01). All patients showed intervertebral fusion at 6 months after the operation. Two patients (5.4%) in the PE-PLIF group experienced complications.

CONCLUSION

Both PE-PLIF and MPLIF surgery were clinically effective and safe for patients with single-segment LDD. PE-PLIF surgery is a promising technique that can be used as an alternative treatment for single-segment LDD.

The Endoscopic Lumbar Interbody Fusion: A Narrative Review, and Future Perspective

Lumbar interbody fusion stands as a preferred surgical solution for degenerative lumbar spine diseases. The procedure primarily aims to establish lumbar segment stability, directly addressing patient symptoms associated with spinal complications. Traditional open surgery, though effective, is linked with notable morbidities and extended recovery time. To mitigate these concerns, minimally invasive surgery (MIS) has garnered significant popularity, presenting an appealing alternative with numerous benefits such as reduced soft tissue trauma, decreased blood loss, and expedited recovery. Among MIS procedures, full endoscopic spinal surgery, characterized by its minimal invasiveness, holds the potential to further minimize morbidities while enhancing surgical outcomes. Endoscopic lumbar interbody fusion, a novel procedure within this paradigm, has gained attention for offering advantages comparable to those of minimally invasive transforaminal lumbar interbody fusion. However, the safety, efficacy, and associated surgical techniques and instrument design of this method continue to be subjects of ongoing debate. This paper critically reviews current evidence on the safety, efficacy, and advantages of endoscopic lumbar spinal interbody fusion, examining whether it could indeed supersede existing mainstream techniques.

Construction and validation of a predictive model for postoperative urinary retention after lumbar interbody fusion surgery

BACKGROUND

Postoperative urine retention (POUR) after lumbar interbody fusion surgery may lead to recatheterization and prolonged hospitalization. In this study, a predictive model was constructed and validated. The objective was to provide a nomogram for estimating the risk of POUR and then reducing the incidence.

METHODS

A total of 423 cases of lumbar fusion surgery were included; 65 of these cases developed POUR, an incidence of 15.4%. The dataset is divided into a training set and a validation set according to time. 18 candidate variables were selected. The candidate variables were screened through LASSO regression. The stepwise regression and random forest analysis were then conducted to construct the predictive model and draw a nomogram. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and the calibration curve were used to evaluate the predictive effect of the model.

RESULTS

The best lambda value in LASSO was 0.025082; according to this, five significant variables were screened, including age, smoking history, surgical method, operative time, and visual analog scale (VAS) score of postoperative low back pain. A predictive model containing four variables was constructed by stepwise regression. The variables included age (β = 0.047, OR = 1.048), smoking history (β = 1.950, OR = 7.031), operative time (β = 0.022, OR = 1.022), and postoperative VAS score of low back pain (β = 2.554, OR = 12.858). A nomogram was drawn based on the results. The AUC of the ROC curve of the training set was 0.891, the validation set was 0.854 in the stepwise regression model. The calibration curves of the training set and validation set are in good agreement with the actual curves, showing that the stepwise regression model has good prediction ability. The AUC of the training set was 0.996, and that of the verification set was 0.856 in the random forest model.

CONCLUSION

This study developed and internally validated a new nomogram and a random forest model for predicting the risk of POUR after lumbar interbody fusion surgery. Both of the nomogram and the random forest model have high accuracy in this study.

Does Immediate Postoperative Early Ambulation Affect Clinical Results of Full-Endoscopic Lumbar Discectomy? A Historical Control Study of Daytime Operation with a 8-Hour Hospital Stay versus Inpatient Operation

OBJECTIVE

Full-endoscopic lumbar discectomy (FELD) is a popular operation for the treatment of lumbar disc herniation (LDH) and day surgery mode is increasingly popular. However, only a few studies have reported about day surgery patients undergoing Percutaneous endoscopic lumbar discectomy (PELD). This retrospective study was to evaluate and analyze the clinical outcomes of patients undergoing FELD for LDH as day surgery versus inpatient surgery.

METHODS

From January 2020 to January 2022, a retrospective analysis of LDH patients treated with FELD either in day surgery unit (within 8-h hospital stay) or inpatient unit was carried out. All these patients were followed-up for at least 12 months, and were categorized into a FELD-I (inpatient surgery) group or a FELD-D (day surgery) group, according to where the surgical procedures were performed. We assessed and compared the postoperative stand and walk time, postoperative hospitalization stays, time of return to work, modified MacNab criteria, willingness to recommend surgery, complications, revision rate, as well as the visual analogue scale (VAS) and the Oswestry disability index score (ODI). Student t-test was used for continuous variables and chi-square test or Fisher's exact test was used for categorical variables.

RESULTS

There was no statistically significant difference in demographic data and baseline characteristics between two groups. And no significant differences were found in MacNab criteria between two groups. Postoperative VAS and ODI scores at one-day postoperation and final follow-up both improved significantly in both groups, as compared to the preoperative data (p < 0.001). However, no significant difference was found between the two groups on the pre, postoperative, or the last follow-up score for VAS and ODI (p > 0.05). The postoperative first ambulation time and postoperative hospital stays was much longer in FELD-I group than FELD-D group (p < 0.001). However, there were no significant differences in the perioperative complications, revision rate as well as satisfaction rate between two groups (p > 0.05). The overall time of return to work of young patients (<60 years-old) in the FELD-D group was significantly shorter than that in the FELD-I group (p = 0.001). Patients in the FELD-D group were more likely to recommend this kind of surgical model.

CONCLUSION

These data suggest that FELD-D can be effectively performed as day surgery (within 8 h hospital stay). Early ambulation after FELD-D did not affect the clinical outcomes and the revision rates. Day surgery patients are more likely to recommend this surgery mode to other patients and younger patients may be able to return to work earlier.

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.

Clinical Outcomes and Radiologic Parameters of Endoscopic Lumbar Interbody Fusion Using a Novel Nerve Baffle with a Minimum 1-year Follow-up

OBJECTIVE

Since endoscopic lumbar interbody fusion procedure has established, the insertion of cage requires a large working tube, which may lead to nerve root irritation. A novel nerve baffle was used for endoscopic lumbar interbody fusion (ELIF) and its short-term outcomes were analyzed.

METHODS

A total of 62 patients (32 cases in tube group, 30 cases in baffle group) with lumbar degenerative diseases who underwent endoscopic lumbar fusion surgery from July 2017 to September 2021 were retrospectively analyzed. Clinical outcomes were measured using pain visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedic Association Scores (JOA), and complications. Perioperative blood loss was calculated using the Gross formula. Radiologic parameters included lumbar lordosis, surgical segmental lordosis, cage position, and fusion rate.

RESULTS

There were significant differences in VAS, ODI, and JOA scores postoperatively, 6 months after operation, and at the last follow-up (P < 0.05) within the 2 groups. The VAS and ODI score and hidden blood loss were significantly lower (P < 0.05) for the baffle group. There was no significant difference in lumbar lordosis and segmental lordosis (P > 0.05). Postoperative disc height was significantly higher than preoperative and follow-up disc heights (P < 0.05) for both groups. There was no statistical difference in fusion rate and cage position parameters or subsidence rate.

CONCLUSIONS

Endoscopic lumbar interbody fusion using the novel baffle has more advantages in nerve protection and hidden blood loss reduction than traditional ELIF with working tube. Compared with the working tube procedure, it has similar or even better short-term clinical outcomes.

Current Indications for Spinal Endoscopic Surgery and Potential for Future Expansion

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

Biomechanical effect of Coflex and X-STOP spacers on the lumbar spine: a finite element analysis

OBJECTIVE

To explore the biomechanical differences between Coflex and X-STOP devices by finite element analysis.

METHODS

Based on the normal lumbar CT images from a healthy adult volunteer, four finite element models including the healthy lumbar segment model, the mild degenerated lumbar segment model, a Coflex fixed lumbar segment model and X-STOP fixed lumbar segment model were constructed. A simulation analysis under the conditions of flexion, extension, lateral bending, and rotation was performed to compare range of motion (ROM), intradiscal pressure, the facet joint force, the maximum Von Mises stress and the peak facet contact forces, between Coflex and X-STOP devices.

RESULTS

Compared to the mild degenerated lumbar segment model at surgical level L4-L5, Coflex and X-STOP could reduce ROM in extension by 98.34% and 95.86%, respectively, decrease peak stress of intervertebral discs in extension by 59.4% and 66.17%, respectively, and release peak force of facet joint in extension by 97.09% and 95.42%, respectively. Both devices had no significant impact on adjacent levels. The maximum Von Mises stress in Coflex device was 637.56 Mpa in flexion, 528.86 Mpa in extension, while the maximum Von Mises stress in X-STOP device was 476.65 Mpa at extension position. The peak facet contact forces of Coflex and X-STOP devices appeared in extension and were 19.76 Mpa and 49.28 Mpa, respectively.

CONCLUSIONS

Coflex and X-STOP devices can effectively decrease the ROM and intradiscal pressure in extension, without affecting the adjacent levels.