Time Course Observation of Outcomes between Minimally Invasive Transforaminal Lumbar Interbody Fusion and Posterior Lumbar Interbody Fusion

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 endoscopic posterior lumbar interbody fusion for the treatment of degenerative lumbar diseases: a technical note and summary of the initial clinical outcomes

BACKGROUND

Percutaneous endoscopic lumbar interbody fusion was a new technique that leads to improved visualization, improved safety and less trauma than does the traditional procedure. The purpose of this study was to introduce the technique of percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) and determine its efficacy.

METHODS

35 patients with an average age of 52.3±13.7 years were treated with single-segment PE-PLIF. The perioperative parameters and the radiographic parameters were measured. The visual analog scale (VAS) score for low back pain, VAS score for leg pain and Oswestry disability index (ODI) score were used to assess the levels of pain and function.

RESULTS

The mean estimated volume of blood loss was 68.6±32.3 ml, operative time was 179.6±31.0 minutes. PE-PLIF significantly reduced the VAS score for low back pain, VAS score for leg pain and ODI score, and improved the posterior disc height, lumbar lordosis angle and segmental lordosis angle (p < 0.05). The rate of satisfaction was 94.3%. One patient suffered a dural tear. There was one case of contralateral radiculopathy that was relieved after conservative treatment.

CONCLUSIONS

This research suggests that PE-PLIF is a minimally invasive, safe, and effective treatment for degenerative lumbar diseases requiring interbody fusion.

The Safety and Effectiveness of Tranexamic Acid in Lumbar Interbody Fusion Surgery: An Updated Meta-analysis of Randomized Controlled Trials

OBJECTIVE

Several previous meta-analyses have been published, followed by additional randomized clinical trials investigating the effects of tranexamic acid (TXA) in patients undergoing posterior lumbar interbody fusion (PLIF) surgery. As a result, the purpose of this research is to present an updated quantitative analysis of the existing literature and to further explicate its effectiveness.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were searched for randomized controlled trials (RCTs) comparing the application of TXA and placebo in patients undergoing PLIF surgery from their establishment to December 31, 2021. Data on clinical outcomes, perioperative outcomes, and complications were collected. The summary statistics for continuous and dichotomous variables were derived as weighted mean difference (WMD) and relative risk (RR), respectively.

RESULTS

A total of 12 studies enrolling 1088 participants were included in this meta-analysis. The combined results revealed that TXA can decrease intraoperative blood loss (WMD: -84.83, P < 0.0001), total blood loss (WMD: -189.93, P < 0.00001), hidden blood loss (WMD: -134.69, P = 0.002), postoperative drainage (WMD: -100.71, P < 0.00001), postoperative hemoglobin loss (WMD: 6.21, P < 0.00001), operative time (WMD: -3.80, P = 0.007), hospital stay (WMD: -1.86, P = 0.001), and transfusion rates (RR: 0.41, P < 0.00001) in PLIF without increasing the risk of thromboembolic events (RR: 0.80, P = 0.43).

CONCLUSIONS

TXA can considerably decrease surgical blood loss, postoperative drainage, reduce operative times, hospital stays, and transfusion rates. Furthermore, the TXA group had lower postoperative hemoglobin drop values than the placebo group.

Percutaneous Endoscopic Posterior Lumbar Interbody Fusion with Unilateral Laminotomy for Bilateral Decompression Vs. Open Posterior Lumbar Interbody Fusion for the Treatment of Lumbar Spondylolisthesis

Background

Endoscopic lumbar interbody fusion is a new technology that is mostly used for single-segment and unilateral lumbar spine surgery. The purpose of this study is to introduce percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) with unilateral laminotomy for bilateral decompression (ULBD) for lumbar spondylolisthesis and evaluate the efficacy by comparing it with open posterior lumbar interbody fusion (PLIF).

Methods

Twenty-eight patients were enrolled in PE-PLIF with the ULBD group and the open PLIF group. The perioperative data of the two groups were compared to evaluate the safety of PE-PLIF with ULBD. The visual analog scale (VAS) back pain, VAS leg pain, and Oswestry Disability Index (ODI) scores of the two groups preoperatively and postoperatively were compared to evaluate clinical efficacy. Preoperative and postoperative imaging data were collected to evaluate the effectiveness of the operation.

Results

No differences in baseline data were found between the two groups (p > 0.05). The operation time in PE-PLIF with the ULBD group (221.2 ± 32.9 min) was significantly longer than that in the PLIF group (138.4 ± 25.7 min) (p < 0.05), and the estimated blood loss and postoperative hospitalization were lower than those of the PLIF group (p < 0.05). The postoperative VAS and ODI scores were significantly improved in both groups (p < 0.05), but the postoperative VAS back pain score in the PE-PLIF group was significantly lower than that in the PLIF group (p < 0.05). The excellent and good rates in both groups were 96.4% according to MacNab’s criteria. The disc height and cross-sectional area of the spinal canal were significantly improved in the two groups after surgery (p < 0.05), with no difference between the groups (p > 0.05). The fusion rates in PE-PLIF with the ULBD group and the PLIF group were 89.3% and 92.9% (p > 0.05), respectively, the cage subsidence rates were 14.3% and 17.9% (p > 0.05), respectively, and the lumbar spondylolisthesis reduction rates were 92.72 ± 6.39% and 93.54 ± 5.21%, respectively (p > 0.05).

Conclusion

The results from this study indicate that ULBD can be successfully performed during PE-PLIF, and the combined procedure is a safe and reliable treatment method for lumbar spondylolisthesis.

Comparison of Outcomes of Lumbar Interbody Fusion and Full-endoscopic Laminectomy for L5 Radiculopathy Caused by Lumbar Foraminal Stenosis

This study compared the outcomes of microendoscopy-assisted lumbar interbody fusion (ME-LIF) and uniportal full-endoscopic laminectomy (FEL) for L5 radiculopathy caused by lumbar foraminal stenosis (LFS). ME-LIF was performed using an 18- to 20-mm tubular retractor and endoscope, and FEL via the translaminar approach (TLA) was performed at the dorsal part of the foramen using a 4.1-mm working channel endoscope. Patients with LFS treated using ME-LIF (n = 39) or FEL-TLA (n = 30) were retrospectively evaluated. Patients' background and operative data were collected. The 36-item Short Form Survey (SF-36), Oswestry Disability Index (ODI), and European Quality of Life-5 Dimension (EQ-5D) scores were recorded preoperatively and 2 years postoperatively. The background data of the two groups (ME-LIF and FEL-TLA) were similar. The mean operation times for ME-LIF and FEL-TLA were 110.7 and 65.2 min, respectively, and the mean length of hospital stay were 10.3 and 1.5 days, respectively. Reoperation was required for surgical site infection, and percutaneous pedicle screw malposition in three patients was treated using ME-LIF. During follow-up, second FEL-TLA and LIF were performed for recurrent L5 radiculopathy in one and three patients in the FEL-TLA group, respectively. Although the SF-36, ODI, and EQ-5D scores 2 years postoperatively improved in both groups, improvement in ODI scores was lower following FEL-TLA than following ME-LIF. FEL-TLA can be performed to treat patients with L5 radiculopathy caused by LFS. Although the ODI score improvement following FEL-TLA was unremarkable, FEL-TLA might be considered because of its better safety profile and minimal invasiveness than ME-LIF.

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.

Clinical outcomes, complications and fusion rates in endoscopic assisted intraforaminal lumbar interbody fusion (iLIF) versus minimally invasive transforaminal lumbar interbody fusion (MI-TLIF): systematic review and meta-analysis

This meta-analysis aims to determine the clinical outcomes, complications, and fusion rates in endoscopic assisted intra-foraminal lumbar interbody fusion (iLIF) and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) for lumbar degenerative diseases. The MEDLINE, Embase, and Cochrane Library databases were searched. The inclusion criteria were: five or more consecutive patients who underwent iLIF or MI-TLIF for lumbar degenerative diseases; description of the surgical technique; clinical outcome measures, complications and imaging assessment; minimum follow-up of 12 months. Surgical time, blood loss, and length of hospital stay were extracted. Mean outcome improvements were pooled and compared with minimal clinically important differences (MCID). Pooled and direct meta-analysis were evaluated. We identified 42 eligible studies. The iLIF group had significantly lower mean intra-operative blood loss, unstandardized mean difference (UMD) 110.61 mL (95%CI 70.43; 150.80; p value < 0.0001), and significantly decreased length of hospital stay (UMD 2.36; 95%CI 1.77; 2.94; p value < 0.0001). Visual analogue scale (VAS) back, VAS leg and Oswestry disability index (ODI) baseline to last follow-up mean improvements were statistically significant (p value < 0.0001), and clinically important for both groups (MCID VAS back > 1.16; MCID VAS leg > 1.36; MCID > 12.40). There was no significant difference in complication nor fusion rates between both cohorts. Interbody fusion using either iLIF or MI-TLIF leads to significant and clinically important improvements in clinical outcomes for lumbar degenerative diseases. Both procedures provide high rates of fusion at 12 months or later, without significant difference in complication rates. iLIF is associated with significantly less intraoperative blood loss and length of hospital stay.

Study registration: PROSPERO international prospective register of systematic reviews: Registration No. CRD42020180980, accessible at https://www.crd.york.ac.uk/prospero/ April 2020.

Minimally invasive transforaminal lumbar interbody fusion: Technical tips, learning curve, short-term clinical outcome, and brief review

Background

Current trends in spine surgeries have shifted to minimally invasive procedures. Minimally invasive approaches are getting more popular for lumbar interbody fusion procedures.

Objectives

The objective of the study was to report technical modifications, learning curve, and short-term clinical results in minimally invasive transforaminal interbody fusion (MITLIF).

Materials and Methods

All MITLIF cases performed from 2018 July to March 2020 were included. First three authors were operating surgeons. Visual analog scores (VAS) scoring for pain, Macnab criteria, and Oswestry disability index (ODI) were used for outcome assessment. Operating time, radiation exposure, and complications were assessed separately in a group of 20 as per time sequence in series to assess the learning curve.

Results

A total of 61 patients were included. Various indications included spondylolisthesis, failed back surgery, calcified lumbar disc, and spondylodiscitis. Mean age was 47.08 ± 12.06. Intraoperative blood loss was 97.04 ± 25.58. Mean operating time and number of C-arm shots were 190.75 ± 37.11 and 159.3 ± 74.54, respectively, in initial 20 cases which however reduced in later operated cases. Significant improvement in VAS and ODI scores was observed at follow-up of 6.34 ± 4.67 months. Three cases needed surgical revision in the initial 20 cases, and there were no revision surgeries in later operated cases.

Conclusion

MITLIF could be done in failed back surgery cases, spondylodiscitis, and deformity corrections in addition to spondylolisthesis. It has advantages of less injury to soft tissues, maintaining the posterior tension band, decrease in blood loss and hospital stays, and early mobilization. However, it has longer learning curve and takes minimum 20 cases for the surgeon to acquire reasonable experience and confidence.

Robot-Assisted Minimally Invasive Transforaminal Lumbar Interbody Fusion in the Treatment of Lumbar Spondylolisthesis

Objective

To compare the clinical efficacy between robot‐assisted minimally invasive transforaminal lumbar interbody fusion (robot‐assisted MIS‐TLIF) and traditional open TLIF surgery in the treatment of lumbar spondylolisthesis.

Methods

According to the inclusion and exclusion criteria, 48 cases with lumbar spondylolisthesis who received surgical treatment from June 2016 to December 2017 in the spinal surgery department of Beijing Jishuitan Hospital were analyzed in this study, including 23 patients who received robot‐assisted MIS‐TLIF and 25 patients who received traditional open TLIF surgery. The two groups were compared in terms of pedicle screw accuracy evaluated by Gertzbein‐Robbins classification on postoperative computed tomography (CT), operation time, blood loss, postoperative drainage, hospitalization, time to independent ambulation, low back pain evaluated by visual analog scale (VAS), lumbar function evaluated by Oswestry Disability Index (ODI), paraspinal muscles atrophy on magnetic resonance imaging (MRI), and complications.

Results

Postoperative CT showed that the rate of Grade A screws in the robot‐assisted MIS‐TLIF group was significantly more than that in the open surgery group (χ² = 4.698, P = 0.025). Compared with the open surgery group, the robot‐assisted MIS‐TLIF group had significantly less intraoperative blood loss, less postoperative drainage, shorter hospitalization, shorter time to independent ambulation, and lower VAS at 3 days post‐operation (P < 0.05). However, the duration of surgery was longer. The VAS of the robot‐assisted MIS‐TLIF group decreased from 6.9 ± 1.8 at pre‐operation to 2.1 ± 0.8 at post‐operation, 1.8 ± 0.7 at 6‐month follow‐up and 1.6 ± 0.5 at 2‐year follow‐up. The VAS of the open surgery group decreased from 6.5 ± 1.7 at pre‐operation to 3.7 ± 2.1 at post‐operation, 2.1 ± 0.6 at 6‐month follow‐up and 1.9 ± 0.5 at 2‐year follow‐up. The ODI of the robot‐assisted MIS‐TLIF group decreased from 57.8% ± 8.9% at pre‐operation to 18.6% ± 4.7% at post‐operation, 15.7% ± 3.9% at 6‐month follow‐up and 14.6% ± 3.7% at 2‐year follow‐up. The ODI of the open surgery group decreased from 56.9% ± 8.8% at pre‐operation to 20.8% ± 5.1% at post‐operation, 17.3% ± 4.2% at 6‐month follow‐up and 16.5% ± 3.8% at 2‐year follow‐up. Paraspinal muscle cross‐sectional area in 2‐year follow‐up in patients of the open surgery group decreased significantly compared to patients of robotic‐assisted MIS‐TLIF group (P = 0.016).

Conclusion

In the treatment of lumbar spondylolisthesis, robot‐assisted MIS‐TLIF may lead to more precise pedicle screw placement, less intraoperative blood loss, less postoperative drainage, less postoperative pain, quicker recovery, and less paraspinal muscle atrophy than traditional open surgery.

Surgical Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion for Highly Migrated Lumbar Disc Herniation

Objective

To describe minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for highly migrated lumbar disc herniation (LDH) and assess its clinical outcomes.

Patients and Methods

This research retrospectively assessed 25 patients who were diagnosed with one-segmental highly migrated LDH and underwent MIS-TLIF in Peking University First Hospital from June 2015 to September 2019. Demographic data, perioperative parameters, complications, recurrence, and surgical outcomes were assessed.

Results

Twelve males and 13 females, with a mean age of 56.68 years old, were involved and the follow-up period was at least one year. The mean operation time was 222.16 minutes, the mean intraoperative hemorrhage was 250.00 mL, and the mean post-operative hospitalization was 5.76 days. The improvements in visual analog scale (VAS) and Oswestry disability index (ODI) were statistically significant. In addition, based on the MacNab criteria, 22 patients (88.0%) acquired satisfactory (good or excellent) results. One patient underwent post-operative epidural hematoma and recovered after evacuation of the hematoma. No recurrence was found.

Conclusion

MIS-TLIF is safe and effective and it can provide satisfactory clinical outcomes for highly migrated LDH.

Relationship between Preoperative Neuroradiological Findings and Intraoperative Bulbocavernosus Reflex Amplitude in Patients with Intradural Extramedullary Tumors

The current study aimed to evaluate the relationship between preoperative neuroradiological findings and intraoperative bulbocavernosus reflex (BCR) amplitude in patients with intradural extramedullary tumors. A total of 24 patients with lesions below the 12th thoracic vertebra were included in the analysis. Objective and subjective urinary symptoms were investigated using data obtained from medical records and the core lower urethral symptom score (CLSS) questionnaire. The lesion compression rate was evaluated with MRI. In the epiconus-to-conus medullaris (Epi-CM) group, BCR amplitude changes were found to be correlated with the compression rate (p <0.05). The preoperative CLSS of the group with a BCR amplitude of <50% was worse than that of the group with ≥50% (p <0.01). The group did not experience symptom improvement 6 months postoperatively based on the CLSS. The preoperative CLSS of the group with compression rate of ≥80% on imaging was worse than that of the group with <80% (p <0.05). In the group with preoperative compression rate of ≥80%, CLSS at 1 month and 6 months postoperatively was improved as compared to preoperative CLSS (p <0.01, p <0.05). Hence, BCR amplitude changes are associated with the degree of lesion compression on preoperative images and pre- and postoperative urinary symptoms. Patients with intradural extramedullary Epi-CM lesions with strong compression are likely to present with low BCR amplitude and worsened postoperative symptoms. It is considered that the risk of postoperative urinary symptoms increases even with careful surgical manipulation under these conditions.

Understanding the Future Prospects of Synergizing Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgery with Ceramics and Regenerative Cellular Therapies

Transforaminal lumber interbody fusion (TLIF) is the last resort to address the lumber degenerative disorders such as spondylolisthesis, causing lower back pain. The current surgical intervention for these abnormalities includes open TLIF. However, in recent years, minimally invasive TLIF (MIS-TLIF) has gained a high momentum, as it could minimize the risk of infection, blood loss, and post-operative complications pertaining to fusion surgery. Further advancement in visualizing and guiding techniques along with grafting cage and materials are continuously improving the safety and efficacy of MIS-TLIF. These assistive techniques are also playing a crucial role to increase and improve the learning curve of surgeons. However, achieving an appropriate output through TLIF still remains a challenge, which might be synergized through 3D-printing and tissue engineering-based regenerative therapy. Owing to their differentiation potential, biomaterials such as stem/progenitor cells may contribute to restructuring lost or damaged tissues during MIS-TLIF, and this therapeutic efficacy could be further supplemented by platelet-derived biomaterials, leading to improved clinical outcomes. Thus, based on the above-mentioned strategies, we have comprehensively summarized recent developments in MIS-TLIF and its possible combinatorial regenerative therapies for rapid and long-term relief.

Biomechanical effects of osteoporosis on adjacent segments after posterior lumbar interbody fusion: A finite element study

Objective:

To investigate the biomechanical effects of osteoporosis on adjacent segments after posterior lumbar interbody fusion (PLIF).

Methods:

This study was designed and conducted in the Traumatology and Orthopedics Laboratory, School of Chinese Medicine, Jinan University, Guangzhou, China, between December 2019 and February 2020. A healthy finite element model of L3-S1 was developed along with one PLIF model and one PLIF with osteoporosis model. Based on a hybrid test method, the inferior surface of S1 was entirely fixed, and a preload of 400N combined with an adjusted moment was imposed on the superior surface of L3 in each model to simulate flexion, extension, lateral bending and axial rotation. The intradiscal pressure (IDP), shear stress on annulus fibrosus, and the range of motion (ROM) of L3-L4 and L5-S1 were calculated and compared.

Results:

In each direction, the highest value of IDP and shear stress on annulus fibrosus at L3-L4 and L5-S1 was found in the PLIF model, and the lowest value in the healthy model. The largest ROM at L4-L5 appeared in the healthy model, and the smallest value in the PLIF model in each direction. At L3-L4 and L5-S1, the highest ROM in most directions was found in the PLIF model, followed by the PLIF with osteoporosis model, and the lowest value in the healthy model.

Conclusions:

Osteoporosis can decrease IDP, shear stress on annulus fibrosus, and ROM at adjacent levels, and slow down the development of ASD after PLIF.

Comparison of Percutaneous Endoscopic Lumbar Discectomy with Minimally Invasive Transforaminal Lumbar Interbody Fusion as a Revision Surgery for Recurrent Lumbar Disc Herniation after Percutaneous Endoscopic Lumbar Discectomy

Objective

The purpose of this study was to compare the outcomes between percutaneous endoscopic lumbar discectomy (PELD) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the revision surgery for recurrent lumbar disc herniation (rLDH) after PELD surgery.

Patients and Methods

A total of 46 patients with rLDH were retrospectively assessed in this study. All the patients had received a PELD in Peking University First Hospital between January 2015 and June 2019, before they underwent a revision surgery by either PELD (n=24) or MIS-TLIF (n=22). The preoperative data, perioperative conditions, complications, recurrence condition, and clinical outcomes of the patients were compared between the two groups.

Results

Compared to the MIS-TLIF group, the PELD group had significantly shorter operative time, less intraoperative hemorrhage, and shorter postoperative hospitalization, but higher recurrence rate (P<0.05). Complication rates were comparable between the two groups. Both groups had satisfactory clinical outcomes at a 12-month follow-up after the revision surgery. The PELD group also showed significantly lower visual analog scale (VAS) scores of back pain and Oswestry disability index (ODI) in one month after the revision surgery, whereas the difference was not detectable at six- and 12-month follow-ups.

Conclusion

Both PELD and MIS-TLIF are effective as a revision surgery for rLDH after primary PELD. PELD is superior to MIS-TLIF in terms of operative time amount of intraoperative hemorrhage and postoperative hospitalization. However, its higher postoperative recurrence rate must be considered and patients should be well informed, when making a decision between the two surgical approaches.

Standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a threaded cylindrical peek cage: report of two cases

We report two cases of a standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a stress-neutral non-expandable cylindrical threaded polyether ether ketone (PEEK) interbody fusion implant. Patients underwent full-endoscopic transforaminal decompression and fusion for symptomatic lateral recess stenosis due to disc herniation, and hypertrophy of the facet joint complex and ligamentum flavum and no more than grade I spondylolisthesis. Lumbar interbody fusion with cages traditionally calls for posterior supplemental fixation with pedicle screws for added stability. A more simplified version of lumbar decompression and fusion without pedicle screws would allow treating patients suffering from stenosis and instability induced sciatica-type low back and leg pain in an outpatient ambulatory surgery center setting (ASC). This would realize a significant reduction in cost as well as the burden to the patient with decreased postoperative pain and earlier return to function. A 62-year-old female patient had surgery at L4/5 for a 6-year history of worsening right sided sciatica-type leg- and low back pain. Another 79-year-old female had the same surgical management at L4/5 for a 5-year history of unrelenting left-sided spondylolisthesis-related symptoms. Both patients had an uneventful postoperative course until the last available follow-up of 24 weeks with greater than 60% VAS and Oswestry disability index (ODI) reductions. There was no evidence of implant expulsion, subsidence, or postoperative instability. We concluded that standalone outpatient lumbar transforaminal endoscopic interbody fusion with a non-expandable threaded cylindrical cage is feasible, and favorable clinical outcomes provide proof of concept to study long-term clinical outcomes in larger groups of patients.