Comparison of Midterm Outcomes between Biportal Endoscopic Transforaminal Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion with Lateral Vertebral Body Screw Fixation for Single Level Spondylolisthesis

Comparison of Midterm Outcomes between Biportal Endoscopic Transforaminal Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion with Lateral Vertebral Body Screw Fixation for Single Level Spondylolisthesis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparison of Midterm Outcomes between Biportal Endoscopic Transforaminal Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion with Lateral Vertebral Body Screw Fixation for Single Level Spondylolisthesis Fu-Cheng Kao, Shih-Feng Hung, Yu-Pao Hsu, Tsung-Ting Tsai, Hung-Kang Wu, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6877590/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Nov, 2025 Read the published version in BMC Musculoskeletal Disorders → Version 1 posted 13 You are reading this latest preprint version Abstract Objective: The purpose of this study is aiming to compare the intra-operative, radiographic, and mid-term clinical outcomes between direct decompression of BE-TLIF and indirect decompression of OLIF in patients with single level spondylolisthesis Method: Between December 2020 and May 2022, patients with single level spondylolisthesis and received either OLIF or BE-TLIF from the authors’ orthopedic departments were selected to enroll in this retrospective study. Results: A total of 34 patients that underwent single-level OLIF and 30 patients that received single-level BE-TLIF in the spine department of our institutions were included. Both groups had similar demographic parameters. BE-TLIF showed significantly less blood loss compared to that of OLIF (p<0.001). The OLIF group yielded shorter operation time than the BE-TLIF group (p=0.002). The improvement in restoration of follow-up segmental lordosis was significantly more in OLIF group than BE-TLIF group (p<0.001). The OLIF group was significantly better in post-operative VAS back pain (p=0.035). The cage subsidence rates between the two groups were not significantly different. The follow-up Oswestry Disability Index (ODI) and overall visual analogue scale were comparable between the 2 groups without significant difference. Conclusion: While OLIF still offers superior results in restoration of lumbar lordotic angle and short term post-operative back pain, the use of endoscopic technique in BE-TLIF may achieve comparable radiographic and clinical outcomes in cage subsidence rate and follow-up VAS back/leg pain compared to the indirect decompression of OLIF. biportal endoscopic lumbar interbody fusion indirect decompression oblique lumbar interbody fusion spondylolisthesis Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Lumbar spinal fusion is a widely performed surgical procedure aimed at alleviating symptoms associated with degenerative disc disease, spinal stenosis, and other spinal pathologies. Over the years, various surgical approaches have been developed to achieve successful fusion while minimizing surgical morbidity and optimizing clinical outcomes[ 1 – 4 ]. Among these approaches, Oblique lumbar interbody Fusion (OLIF) and transforaminal lumbar interbody fusion have gained popularity for their purported advantages in terms of minimally invasive access and preservation of anatomical structures[ 5 – 7 ]. Although minimally invasive TLIF (MIS-TLIF) reduces iatrogenic damage to the paravertebral soft tissues, the technique still requires open incision. With the advancement in endoscopic technique, percutaneous endoscopic technique has been used in not only discectomy but also in spinal decompression and interbody fusion[ 8 , 9 ]. The endoscopic transforminal lumbar interbody fusion allows access to the diseased level of the spine for direct decompression and spinal fusion with minimal damage to the surrounding soft tissue, which could potentially improve recovery time and the overall clinical outcome[ 10 , 11 ]. On the other hand, OLIF achieves indirect decompression by accessing lumbar disc through the space between psoas muscle and aorta without disrupting the paravertebral soft tissues and facet joints[ 12 ]. Several studies have showed superior clinical outcomes in OLIF compared to MIS-TLIF in mild to moderate lumbar degenerative disease. In Hung et al, the group of OLIF without posterior instrumentation showed significant improvement in post-operative Oswestry Disability Index(ODI) and visual analogue scale (VAS) for back pain compared to the MIS-TLIF group[ 13 ]. Liu et. al demonstrated lower incidence of postoperative low back pain and faster postoperative recovery in the patients received OLIF over the group received MIS-TLIF[ 14 ]. However, to author’s knowledge, there has been no study that directly compares the Endo-TLIF and OLIF evaluating the clinical and radiographic outcomes. The purpose of this study is aiming to compare the intra-operative, radiographic, and mid-term clinical outcomes between biportal endoscopic TLIF (BE-TLIF) and OLIF in patients with lumbar degenerative disease. Material and Method Study population and surgical techniques Between December 2020 and May 2022, a retrospective review was conducted from the spine department of the two institutions to identify all patients that underwent either OLIF or BE-TLIF procedure. Each surgical technique was performed by either one of the two experienced spine surgeons, and the selection of technique was based on the surgeon’s preference and the accessibility of the working corridor (space between aorta and psoas muscle). All surgical procedures were done in either one of the two orthopedic departments of the institutions. Inclusion criteria were patients with single level degenerative spondylolisthesis (Meyerding grade ≤ 2) and accompanied with either clinical sciatica, neurogenic intermittent claudication, or mechanical low back pain caused by segmental instability. Patients included also received primary single lumbar level surgery between L2 to L5, and had at least 3 years of post-operative follow-up. Exclusion criteria were spinal infection, benign or malignant spinal tumor, multiple level of spinal surgery, revision spinal surgery, incomplete radiographic image, and any patients with less than 3 years of follow-up. The demographic parameters included sex, age, body mass index (BMI), operation time, intra-operative blood loss, days of hospitalization, smoking history, and history of diabetic mellitus. Medical records, laboratory data, radiographic images, and patient reported functional data of these patients were analyzed. This study received institutional review board approval, and the need to obtain informed patient consent was waived due to the retrospective nature of the study. All procedures performed in this study met with the ethical standards of the national research committee. The data of patients were anonymized and maintained with confidentiality. Surgical techniques Each patient in the BE-TLIF group received biportal endoscopic transforaminal lumbar interbody fusion using the method from Yu et. al.[ 15 ]. The patient received intubated general anesthesia and was placed in prone position. Two ipsilateral skin incisions were made over center of trajectory line of upper and lower pedicle under fluoroscope (Fig. 1). The direction of the approach was chosen depending on which side of the patient’s symptom was more severe. The incision wounds were used for screws and scope entrance. Muscles were gently detached from the lamina surface using periosteal elevator. The scope was inserted via working portal and a radiorequency probe was inserted via working portal, which formed triangulation of biportal endoscope was established. Discectomy and laminotomy were done. Bilateral decompression was performed by over the top approach in every patient. After endplate preparation, a 10-12mm polyetheretherketone (PEEK) bullet-shaped cage that filled with autograft bone and demineralized bone matrix was inserted (Fig. 2). Percutaneous pedicle screws insertion was then applied via the previously incised skin portals. Finally a Hemovac drain was inserted via one of the incision wound (Fig. 1). For the OLIF group, anterolateral OLIF procedure was done by making an incision around 4cm ventral to the anterior border of the desired intervertebral disc. Blunt dissection through lateral abdominal muscles was done to approach the disc space in the oblique corridor. Mild retraction was done on the psoas muscle. The ORACLE cage (Depuy Company) that filled with cancellous allopathic bone graft was inserted. The cage size larger than pre-operative disc height was chosen for the purpose of augmentation in neuroforamen. The spinal indirect decompression was achieved by cage insertion without laminectomy or posterior instrumentation and lateral vertebral body fixation with pedicle screws was then used for cage fixation (Fig. 3A-B). Radiography Definite diagnosis of each patient was confirmed via pre-operative magnetic resonance imaging (MRI) and plain film. Postoperative radiographic images were taken at postoperative day 1, 1 month, 3 months, 6 months and then every year. Segmental lordotic angle (SLA), disc height (DH), cage subsidence (CS), screws halo sign, and coronal tilting angle (CTA) were recorded by two investigators and rechecked by the other two investigators. SLA was recorded using lateral view of lumbar spine X-ray image by measuring the angle between upper end plate of vertebral body to lower endplate of lower vertebral body (Fig. 4A). Disc height was measured as the distance from mid-position of upper endplate to lower endplate of two vertebral body. CTA was evaluated by measuring the Cobb angle of lumbar antero-posterior view on the X-ray (Fig. 4B). The evaluations for Halo sign and CS were assessed 6 months post-operatively. CS was defined as cage migration greater than 2-mm under X-ray. The presence of trabeculae bridging between the vertebral endplate and cage without gap under the X-ray signified the occurrence of complete spine fusion. Clinical functioning Clinical functional outcomes were evaluated using VAS and ODI. The evaluations and data collection were done during pre-operation, 3 days after operation, and most recent follow-up. All procedures performed in this study were met with the ethical standards of the national research committee. Statistical Analysis Statistical calculations were performed using SPSS 27.0 to analyze the parameters in both groups of patients. All quantitative variables were presented as mean standard deviation, and qualitative variables were shown in terms of ratio and number. Continuous variables were evaluated by independent t-test. The categorical variables were performed by Chi-square test. A P value < 0.05 was considered to be statistically significance. Result Between December 2020 and September 2022, a total of 40 patients that underwent OLIF and 32 patients that received BE-TLIF in the spine department of the two institutions were enrolled. For a total of 40 OLIF patients, 6 of them were excluded from this study due to loss of follow-ups, multiple level of lumbar surgery, history of surgery at the lumbar level, or incomplete radiographic data. Among the 32 BE-TLIF patients, 2 of them were excluded because the surgical site involved sacral (S1) level. After the screening, 34 OLIF patients (12 females, 22 males) and 30 BE-TLIF patients (13 females, 17 males) were enrolled in this study. The demographics for OLIF and BE-TLIF groups were comparatively matched. The mean ages for OLIF and the BE-TLIF were 60.3 years old and 58.4 years old, respectively (p = 0.618). The mean BMI for OLIF was 27.2 kg/m 2 and BE-TLIF patients had an average of 24.9 kg/m 2 (p = 0.594). Three patients in the OLIF group had smoking history while the BE-TLIF group had 2 (p = 0.679). Among the OLIF group, 6 patients from the OLIF group had history of diabetes mellitus while the BE-TLIF group had 4 (p = 0.5.95). The average follow-up for BE-TLIF was 40 months and 43 months for OLIF (p = 0.727) (Table. 1). The mean operation time for OLIF was significantly shorter than that of BE-TLIF (136.5 ± 34.84 vs 188.5 ± 32.56, p = 0.002). The patients received OLIF procedure had an average of 5.38 days of hospitalization compared to 5.01 days of the BE-TLIF patients (p = 0.687). Blood loss during operation was also significantly less in the BE-TLIF compared to the OLIF (32.33 ± 30.11 ml vs 108.5 ± 27.02 ml, p < 0.001) (Table. 2). Radiographic Outcomes The segmental lordotic angle (SLA) increased from a mean of 13.21 preoperatively to 15.61 postoperatively in the OLIF group and the BE-TLIF group went from a mean of 10.59 preoperatively to 11.13postoperatively (Table. 3). The immediate SLA change between the BE-TLIF group and OLIF group was significantly different (0.54 ± 0.39 vs 2.40 ± 2.29, respectively, p = 0.041). The follow-up SLA change in the OLIF and BE-TLIF groups (2.69 ± 1.54 vs -0.22 ± 0.89, respectively, p < 0.001) showed significant difference. The CTA for the OLIF group was 6.57 ± 5.42 preoperatively, 2.88 ± 2.55 postoperatively, and 3.75 ± 4.05 follow-up; BE-TLIF group had CTA of 5.94 ± 4.76 preoperatively, 2.74 ± 1.99 postoperatively, and 2.30 ± 2.56 follow-up. No significant difference was noted in post-operative and follow-up CTA change (CTAC) between the 2 groups (p = 0.512, 0.481, respectively). The pre-operative DH was 7.51 ± 1.33 millimeter in the OLIF group and 6.54 ± 1.56 millimeter in the Endo-TLIF group (p = 0.112). The post-operative disc height improved in OLIF and BE-TLIF groups (10.39 ± 1.25 vs 9.44 ± 1.59, p = 0.347) and the follow-up DH decreased slightly in both group (9.48 ± 1.04 vs 8.29 ± 1.45, p = 0.214). Both the immediate DH change and follow up DH change between the 2 groups showed no significant difference (p = 0.402, 0.385, respectively). Lastly, CS and screws halo sign were noted in 8 out of 34 OLIF patients and 6 out of 30 BE-TLIF patients (p = 0.531). The fusion rate at 12th month for BE-TLIF was 73.3% (24 out of 30) and 73.5% (25 out of 34) for OLIF (p = 0.811); The fusion rate at 24th month for BE-TLIF was 93.3% (28 out of 30) and 91.2% (31 out of 34) for OLIF (p = 0.791) Functional Outcomes The mean pre-operative VAS back pain scores were similar between the OLIF group and the BE-TLIF group (6.53 ± 1.14 vs 6.01 ± 1.52, p = 0.654) (Table.2). The post-operative back pain (3 days after surgery) scores were 0.94 ± 0.91 for the OLIF patients and 2.61 ± 1.67 for the BE-TLIF patients, and the difference was significant (p = 0.035). There was no significant difference in back pain score between the OLIF group and the BE-TLIF group for the most recent follow up (0.63 ± 0.47 vs 0.72 ± 0.59, p = 0.336). Pre-operative leg pain scores for the OLIF group and BE-TLIF group were 6.37 ± 1.11 and 6.92 ± 1.21, respectively (p = 0.395); post-operative leg pain scores (3 days after the surgery) were 0.77 ± 0.73 and 0.87 ± 0.74 (p = 0.776). The preoperative ODI’s were comparable between the 2 groups (OLIF: 60.09 ± 5.99, BE-TLIF: 64.2 ± 13.81, p = 0.403); the follow-up ODI’s were 22.79 ± 9.42 for OLIF and 27.99 ± 14.32 for BE-TLIF (p = 0.265). The ODI improvement 6 months after surgery between the 2 groups showed no significant difference (OLIF: 37.30 ± 8.77, BE-TLIF: 36.21 ± 8.91, p = 0.784). There were 4 patients from the BE-TLIF with intermittent claudication 1 month after the operation, and 5 patients from the OLIF group showed the symptom (p = 0.807), Discussion The lumbar interbody fusion options for degenerative lumbar spinal stenosis are categorized into two main types: direct decompression and indirect decompression. Direct decompression involves a posterior-only approach to remove bone spurs, ligament, cyst, or disc material causing nerve impingement, followed by instrumented fusion using screws and an interbody technique such as TLIF[ 16 – 18 ]. Indirect decompression, on the other hand, involve inserting a large interbody device through an abdominal approach[ 19 , 20 ]. This method restores disc height and spinal canal dimensions by stretching the ligaments, thereby relieving nerve root impingement without removing any posterior osteoligamentous complex. Recent studies have compared the clinical outcomes between direct decompression and indirect decompression of lumbar interbody fusion. Koike et al. compared OLIF with lateral screw fixation and MIS-TLIF in patients received single level lumbar interbody fusion, and while both groups showed postoperative improvements in the clinical outcome scores of all Japanese orthopaedic association back pain evaluation questionnaire (JOABPEQ) domains, the OLIF group showed significant higher rate increase in the psychological domain compared to the MIS-TLIF[ 21 ]. Lin et al. demonstrated that OLIF was superior in time of fusion, restoration of disc height, intraoperative blood loss, and surgery time[ 22 ]. However, there are instances where direct decompression is preferred over indirect decompression of lumbar interbody fusion, such as revision spine surgery, less discrepancy of the disc height on postural change, and surgical corridor access not available[ 23 , 24 ]. In our study, the BE-TLIF showed similar post-operative clinical outcomes compared to the OLIF except immediate post-operative back pain and segmental lordotic angle improvement. However, by minimizing the iatrogenic damage to the paraspinal soft tissue and with significantly less intraoperative blood loss (demonstrated in our study) using endoscopic technique, the BE-TLIF was able to provide similar clinical midterm outcomes compared to OLIF Endplate injury is considered as a detrimental factor for cage subsidence[ 25 – 27 ]. In Calek et. al., weakening of the endplate during the endplate preparation via rasping significantly reduces the axial endplate resistance to subsidence by 15% in the patients received TLIF[ 28 ]. In a systemic review by Parisien et. al., the cage subsidence of TLIF was higher than that of OLIF[ 29 ]. However, our result demonstrated that the rate of cage subsidence was comparable between the BE-TLIF group and the OLIF group. Cage subsidence rate could be reduced if endplate injury was minimized and thoroughly prepared. In our study, the endoscope was able to reach near the annulotomy site and the disc space was visually seen and cleaned using radiofrequency probe. By using the endoscopic technique, the chance of bony endplate injury could be reduced. Neurogenic intermittent claudication is the most common symptom associated with lumbar spinal canal stenosis. In Morishita et al., the increase in changes of local pressure of the intervertebral foramen was significantly associated with the severity of post-operative intermittent claudication in patients with decompression of spinal canal[ 30 ]. The study further suggested that dynamic mechanical stress on the lumbar spinal nerve roots, rather than static mechanical stress associated with different postures or nerve root ischemia, may be the primary cause. Zhu et al. stated that OLIF was found to be effective for dynamic radicular pain, which is mostly relieved during rest[ 5 ]. In our study, the percentage of patients with post-operative intermittent claudication was lower in the BE-TLIF (13.3%) compared to OLIF (14.7%), although the difference was not statistically significant. While dynamic mechanical stress on the spine nerve roots may be the primary cause for intermittent claudication, the static mechanical stress on the lumbar nerve roots couldn’t be completely relieved by OLIF. BE-TLIF, on the other hand, was able to achieve direct decompression. Our result was consistent with the studies mentioned above. A recent study found that the rate of dysesthesia in Endo-TLIF was higher compared to standard uniportal endoscopic procedures, likely due to the larger outer diameter of the Endo-TLIF cannula (14–16 mm) and the strong vibrations experienced during cannula placement and expandable cage insertion[ 31 ]. Additionally, several studies have indicated that during endoscopy-guided interbody cage placement, smaller fusion cages had to be used because conventional cages were too large to pass through the working portal[ 32 – 35 ]. As a result, some surgeons preferred biportal endoscopic technique. Xie et al. stated that compared with unilateral portal lumbar interbody fusion, biportal lumbar interbody fusion had shorter operative time and a higher fusion rate[ 36 ]. Biportal technique offers wider vision of surgical site, greater maneuverability of instruments, more cage size selection, and more efficient decompression range. We chose facetectomy instead of the biportal trans-Kambin approach performed in other recent studies[ 31 , 37 ]. Although the facet joint was not spared, we limited the disruption of the nerve roots caused by cannula insertion. Only two patient reported post-operative transient dysesthesia in our study, and the symptom resolved within 3 months after the operation. Despite high learning curve and technically demanding (significantly longer operation time in BE-TLIF compared to OLIF from our study), the biportal endoscopic technique offers direct inspection to the site. The risk of neural element injury is reduced by using nerve retractor to retract the dura gently through the working portal when inserting the inter-body cage. There are some limitations in our study. First of all, this was a retrospective study with small sample size in each group. Secondly, although this was a multi-centers study, the overall samples were not randomized, which may have led to selection bias. In addition, some data such as bone mass density and follow-up computer tomography were not available in each patient, which could’ve provided some additional insight regarding cage subsidence and fusion rate. Lastly, the follow-up period was relatively short. The larger prospective studies in the future are needed to confirm the clinical outcomes. Conclusion In conclusion, the endoscopic lumbar interbody fusion is becoming popular surgical techniques for the treatment of lumbar degenerative disease, offering significant improvements in radiographic parameters and clinical outcomes. While OLIF still offers superior results in restoration of lumbar lordotic angle and short term post-operative back pain, the use of endoscopic technique in BE-TLIF could potentially achieve comparable radiographic and clinical outcomes in cage subsidence rate and follow-up VAS back/leg pain compared to the indirect decompression of OLIF. However, larger prospective studies in the future are needed to confirm the long term clinical outcomes. Declarations Ethics approval and consent to participate: This study was approved by the Institutional Review Board (IRB) of Ministry of Health and Welfare Taoyuan General Hospital and Chang Gung Medical Foundation (IRB approval number: TYGH 113001; 202401613B0). The need to obtain informed patient consent was waived due to the retrospective nature of the study. All procedures performed in this study met with 1964 Declaration of Helsinki and the ethical standards of the national research committee. The data of patients were anonymized and maintained with confidentiality. Human Ethics and Consent to Participate declarations: not applicable Consent for publication: not applicable due to restrospective study Data sharing : not applicable to this article as no datasets were generated or analysed during the current study Clinical trial number: not applicable Availability of data and materials: The data of patients were anonymized and maintained with confidentiality. Competing interests: Each author certifies that he has no commercial associations. Funding: None Conflict of Interest: Each author certifies that he has no commercial associations. Disclosure of Funding: None. Author Contribution CH Yu contributed to the study conception and design. SH Hung performed the data collection and analysis. SH Hung and FC Kao contributed equally to this manuscript draft. All authors critically reviewed the manuscript for important intellectual content. All authors approved the final version of the manuscript. References Mobbs RJ, Phan K, Malham G, Seex K, Rao PJ. Lumbar interbody fusion: techniques, indications and comparison of interbody fusion options including PLIF, TLIF, MI-TLIF, OLIF/ATP, LLIF and ALIF. J Spine Surg. 2015;1(1):2–18. Foley KT, Holly LT, Schwender JD. Minimally invasive lumbar fusion. Spine. 2003;28(15S):S26–35. Park Y, Ha JW. Comparison of one-level posterior lumbar interbody fusion performed with a minimally invasive approach or a traditional open approach. Spine. 2007;32(5):537–43. Bagby GW. Arthrodesis by the distraction-compression method using a stainless steel implant. In., vol. 11: SLACK Incorporated Thorofare, NJ; 1988: 931–934. Zhu HF, Fang XQ, Zhao FD, Zhang JF, Zhao X, Hu ZJ, Fan SW. Comparison of Oblique Lateral Interbody Fusion (OLIF) and Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) for Treatment of Lumbar Degeneration Disease: A Prospective Cohort Study. Spine (Phila Pa 1976). 2022;47(6):E233–42. Yang J, Liu C, Hai Y, Yin P, Zhou L, Zhang Y, Pan A, Zhang Y, Zhang L, Ding Y et al. Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Spinal Stenosis: Preliminary Report of Seven Cases with 12-Month Follow-Up. Biomed Res Int 2019, 2019:3091459. Peng CWB, Yue WM, Poh SY, Yeo W, Tan SB. Clinical and radiological outcomes of minimally invasive versus open transforaminal lumbar interbody fusion. Spine. 2009;34(13):1385–9. Wang MY, Grossman J. Endoscopic minimally invasive transforaminal interbody fusion without general anesthesia: initial clinical experience with 1-year follow-up. NeuroSurg Focus. 2016;40(2):E13. Jacquot F, Gastambide D. Percutaneous endoscopic transforaminal lumbar interbody fusion: is it worth it? Int Orthop. 2013;37:1507–10. Lee CK, Park JY, Zhang HY. Minimally invasive transforaminal lumbar interbody fusion using a single interbody cage and a tubular retraction system: technical tips, and perioperative, radiologic and clinical outcomes. J Korean Neurosurg Soc. 2010;48(3):219–24. Zhou Y, Zhang C, Wang J, Chu T-w, Li C-q, Zhang Z-f. Zheng W-j: Endoscopic transforaminal lumbar decompression, interbody fusion and pedicle screw fixation——a report of 42 cases. Chin J Traumatol. 2008;11(04):225–31. Heo DH, Choi WS, Park C-K, Kim J-S. Minimally Invasive Oblique Lumbar Interbody Fusion with Spinal Endoscope Assistance: Technical Note. World Neurosurg. 2016;96:530–6. Hung S-F, Liao J-C, Tsai T-T, Li Y-D, Chiu P-Y, Hsieh M-K, Kao F-C. Comparison of outcomes between indirect decompression of oblique lumbar interbody fusion and MIS-TLIF in one single-level lumbar spondylosis. Sci Rep. 2021;11(1):12783. Liu L, Xue H, Han Z, Jiang L, Chen L, Wang D. Comparison between OLIF and MISTLIF in degenerative lumbar stenosis: an age-, sex-, and segment-matched cohort study. Sci Rep. 2023;13(1):13188. Yu C-H, Wu H-K. Biportal Endoscopic Transforaminal Lumbar Interbody Fusion with Percutaneous Instrumentation: A Technical Note. J Minim Invasive Spine Surg Tech 2024, 0. Formica M, Quarto E, Zanirato A, Mosconi L, Vallerga D, Zotta I, Baracchini ML, Formica C, Felli L. Lateral Lumbar Interbody Fusion: What Is the Evidence of Indirect Neural Decompression? A Systematic Review of the Literature. Hss j. 2020;16(2):143–54. Fujibayashi S, Hynes RA, Otsuki B, Kimura H, Takemoto M, Matsuda S. Effect of indirect neural decompression through oblique lateral interbody fusion for degenerative lumbar disease. Spine (Phila Pa 1976). 2015;40(3):E175–182. Kepler CK, Sharma AK, Huang RC, Meredith DS, Girardi FP, Cammisa FP Jr., Sama AA. Indirect foraminal decompression after lateral transpsoas interbody fusion. J Neurosurg Spine. 2012;16(4):329–33. Malham GM, Parker RM, Goss B, Blecher CM. Clinical results and limitations of indirect decompression in spinal stenosis with laterally implanted interbody cages: results from a prospective cohort study. Eur Spine J. 2015;24(Suppl 3):339–45. Ozgur BM, Aryan HE, Pimenta L, Taylor WR. Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion. Spine J. 2006;6(4):435–43. Koike Y, Kotani Y, Terao H, Iwasaki N. Comparison of Outcomes of Oblique Lateral Interbody Fusion with Percutaneous Posterior Fixation in Lateral Position and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis. Asian Spine J. 2021;15(1):97–106. Lin GX, Akbary K, Kotheeranurak V, Quillo-Olvera J, Jo HJ, Yang XW, Mahatthanatrakul A, Kim JS. Clinical and Radiologic Outcomes of Direct Versus Indirect Decompression with Lumbar Interbody Fusion: A Matched-Pair Comparison Analysis. World Neurosurg. 2018;119:e898–909. Yingsakmongkol W, Jitpakdee K, Kerr S, Limthongkul W, Kotheeranurak V, Singhatanadgige W. Successful Criteria for Indirect Decompression With Lateral Lumbar Interbody Fusion. Neurospine. 2022;19(3):805–15. Limthongkul W, Praisarnti P, Tanasansomboon T, Prasertkul N, Kotheeranurak V, Yingsakmongkol W, Singhatanadgige W. An Expanded Surgical Corridor of Oblique Lateral Interbody Fusion at L4-5: A Magnetic Resonance Imaging Study. Neurospine. 2023;20(4):1450–6. Singhatanadgige W, Sukthuayat A, Tanaviriyachai T, Kongtharvonskul J, Tanasansomboon T, Kerr SJ, Limthongkul W. Risk factors for polyetheretherketone cage subsidence following minimally invasive transforaminal lumbar interbody fusion. Acta Neurochir (Wien). 2021;163(9):2557–65. Wu H, Shan Z, Zhao F, Cheung JPY. Poor Bone Quality, Multilevel Surgery, and Narrow and Tall Cages Are Associated with Intraoperative Endplate Injuries and Late-onset Cage Subsidence in Lateral Lumbar Interbody Fusion: A Systematic Review. Clin Orthop Relat Res. 2022;480(1):163–88. Zhou ZJ, Xia P, Zhao FD, Fang XQ, Fan SW, Zhang JF. Endplate injury as a risk factor for cage retropulsion following transforaminal lumbar interbody fusion: An analysis of 1052 cases. Med (Baltim). 2021;100(5):e24005. Calek A-K, Cornaz F, Suter M, Fasser M-R, Farshad M, Widmer J. Endplate weakening during cage bed preparation significantly reduces endplate load capacity. Eur Spine J. 2024;33(7):2621–9. Parisien A, Wai EK, ElSayed MSA, Frei H. Subsidence of Spinal Fusion Cages: A Systematic Review. Int J Spine Surg. 2022;16(6):1103–18. Morishita Y, Hida S, Naito M, Arimizu J, Takamori Y. Neurogenic Intermittent Claudication in Lumbar Spinal Canal Stenosis: The Clinical Relationship Between the Local Pressure of the Intervertebral Foramen and the Clinical Findings in Lumbar Spinal Canal Stenosis. Clin Spine Surg. 2009;22(2):130–4. Morgenstern C, Yue JJ, Morgenstern R. Full percutaneous transforaminal lumbar interbody fusion using the facet-sparing, trans-kambin approach. Clin Spine Surg. 2020;33(1):40–5. Ahn Y, Youn MS, Heo DH. Endoscopic transforaminal lumbar interbody fusion: a comprehensive review. Expert Rev Med Dev. 2019;16(5):373–80. Zhang Y-W, Xia W-H, Gao W-C, Xiao X, Xiao Y, Gong F-P. Direct foraminoplasty in endoscope-assisted transforaminal lumbar interbody fusion for the treatment of lumbar disc herniation. J Int Med Res. 2020;48(1):0300060519875372. Hwa Eum J, Hwa Heo D, Son SK, Park CK. Percutaneous biportal endoscopic decompression for lumbar spinal stenosis: a technical note and preliminary clinical results. J Neurosurg Spine. 2016;24(4):602–7. Heo DH, Son SK, Eum JH, Park CK. Fully endoscopic lumbar interbody fusion using a percutaneous unilateral biportal endoscopic technique: technical note and preliminary clinical results. Neurosurg Focus. 2017;43(2):E8. Xie YZ, Shi Y, Zhou Q, Feng CQ, Zhou Y, Li T, Yu Y, Fan XH. Comparison of the safety and efficacy of unilateral biportal endoscopic lumbar interbody fusion and uniportal endoscopic lumbar interbody fusion: a 1-year follow-up. J Orthop Surg Res. 2022;17(1):360. Kuo K-P, Choi D-J. Biportal Endoscopic Trans-Kambin Lumbar Interbody Fusion: Surgical Techniques and Treatment Outcomes. J Minim Invasive Spine Surg Tech. 2024;9(Suppl 1):S24–33. Tables Table 1. Demographic parameters BE-TLIF OLIF p-value Number of patients 30 34 Age 58.4±10.2 60.3±11.9 0.618 Sex (Male: Female) 17:13 22:12 0.723 Smoker 2 3 0.679 BMI (kg/m 2 ) 24.9±3.7 27.2±5.2 0.594 Diabetes Mellitus 4 6 0.595 Mean F/U (months) 40 43 0.727 Herniated Intervertebral Disc 2 3 0.599 Lumbar Spinal Stenosis 24 27 0.601 Surgery Level -L2/3 -L3/4 -L4/5 2 8 20 2 7 25 0.679 0.416 0.515 Values are mean± standard deviation OLIF: oblique lateral lumbar interbody fusion BE-TLIF: Percutaneous biportal endoscopic transforaminal lumbar interbody fusion BMI: body mass index F/U: follow-up *: p<0.05, statistical significance Diabetes Mellitus: either type 1 or type 2 Table 2. Perioperative and clinical outcomes BE-TLIF OLIF p-value Blood loss 32.33±30.11 108.50±27.02 *<0.001 Operation time 188.50±32.56 136.50±34.84 *0.002 Days of hospitalization 5.01±1.15 5.19±4.12 0.687 Pre VAS back pain 6.01±1.52 6.53±1.14 0.654 Post VAS back pain 2.61±1.67 0.94±0.91 *0.035 F/U VAS back pain 0.72±0.59 0.63±0.47 0.336 Pre VAS leg pain 6.92±1.21 6.37±1.11 0.395 Post VAS leg pain 0.87±0.74 0.77±0.73 0.776 Pre ODI 64.2±12.81 60.09±5.99 0.403 Follow-up ODI 27.99±14.32 22.79±9.42 0.265 ODI improvement 36.21±8.91 37.30±8.77 0.784 Claudication (pre) 20 23 0.742 Claudication (post) 4 5 0.807 Values are mean± standard deviation ODI: Oswestry Disability Index VAS: visual analogue scale Post: post-operative F/U: most recent follow-up Claudication (post): intermittent claudication (1 month after surgery) *: p<0.05, statistical significance Table 3. Radiographic outcomes BE-TLIF OLIF p-value Pre SLA 10.59±8.57 13.21±6.28 0.502 Post SLA 11.13±7.27 15.61±7.94 0.115 F/U SLA 10.91±5.86 15.9±7.2 0.127 Post SLA change 0.54±0.39 2.40±2.29 *0.041 F/U SLA change -0.22±0.89 2.69±1.54 *<0.001 Pre CTA 5.94±4.76 6.57±5.42 0.495 Post CTA 2.74±1.99 2.88±2.55 0.512 F/U CTA 2.30±2.56 3.75±4.05 0.192 Post CTA change -3.20±1.03 -3.69±3.13 0.481 F/U CTA change -2.95±1.87 -2.82±2.03 0.133 Pre disc height 6.54±1.56 7.51±1.33 0.112 Post disc height 9.44±1.59 10.39±1.25 0.347 F/U disc height 8.29±1.45 9.48±1.04 0.214 Post disc height change 2.90±1.73 3.28±1.41 0.402 F/U disc height change 1.75±1.25 1.97±1.01 0.385 Post cage subsidence Yes 6 8 0.531 No 24 26 Post halo sign Yes 6 8 0.531 No 24 26 Fusion rate Complete (12 months) 22 25 0.811 Incomplete (12 months) 8 9 Complete (24 months) 28 31 0.791 Incomplete (24 months) 2 3 Values are mean± standard deviation SLA: segmental lordotic angle CTA: coronal tilting angle Post: post-operative (3 days after surgery) F/U: most recent follow-up *: p<0.05, statistical significance Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 04 Nov, 2025 Read the published version in BMC Musculoskeletal Disorders → Version 1 posted Editorial decision: Revision requested 15 Sep, 2025 Reviews received at journal 12 Sep, 2025 Reviewers agreed at journal 06 Sep, 2025 Reviews received at journal 28 Jul, 2025 Reviews received at journal 19 Jul, 2025 Reviewers agreed at journal 17 Jul, 2025 Reviewers agreed at journal 13 Jul, 2025 Reviewers agreed at journal 12 Jul, 2025 Reviewers invited by journal 11 Jul, 2025 Editor assigned by journal 09 Jul, 2025 Editor invited by journal 18 Jun, 2025 Submission checks completed at journal 17 Jun, 2025 First submitted to journal 17 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6877590","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":484778332,"identity":"4e2a8a9d-4fde-434d-a254-92b70b222e03","order_by":0,"name":"Fu-Cheng Kao","email":"","orcid":"","institution":"Chang Gung Memorial Hospital, Chang Gung University College of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Fu-Cheng","middleName":"","lastName":"Kao","suffix":""},{"id":484778333,"identity":"ea596d97-2667-4b33-8bf0-24d0d25eedfc","order_by":1,"name":"Shih-Feng Hung","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Shih-Feng","middleName":"","lastName":"Hung","suffix":""},{"id":484778334,"identity":"2a394ce9-88bf-4a0f-8607-3ea3ec32420b","order_by":2,"name":"Yu-Pao Hsu","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Yu-Pao","middleName":"","lastName":"Hsu","suffix":""},{"id":484778335,"identity":"79de827d-5234-4147-ba92-0445444499e6","order_by":3,"name":"Tsung-Ting Tsai","email":"","orcid":"","institution":"Chang Gung Memorial Hospital, Chang Gung University College of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Tsung-Ting","middleName":"","lastName":"Tsai","suffix":""},{"id":484778336,"identity":"beb44463-4523-4646-9e13-217f1bb14a64","order_by":4,"name":"Hung-Kang Wu","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Hung-Kang","middleName":"","lastName":"Wu","suffix":""},{"id":484778340,"identity":"76e40202-9581-4ec9-9ccc-6c22fab59c43","order_by":5,"name":"Ming-Te Cheng","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Ming-Te","middleName":"","lastName":"Cheng","suffix":""},{"id":484778341,"identity":"f221e57e-c76d-404f-869a-6f8bfb382bf7","order_by":6,"name":"Kuang-Kai Hsueh","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Kuang-Kai","middleName":"","lastName":"Hsueh","suffix":""},{"id":484778342,"identity":"061c9f36-01ab-4269-b8ac-3bab3c34fe41","order_by":7,"name":"Po-Yuan Lin","email":"","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":false,"prefix":"","firstName":"Po-Yuan","middleName":"","lastName":"Lin","suffix":""},{"id":484778344,"identity":"cf2a7ca1-654f-40f3-9d2b-8d26b8bc0c18","order_by":8,"name":"Ching-Hsiao Yu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYHACxgMPGCRk2Ngb2z98YGBIIErPgQQGCR4+nsPHGGcgaZEgoIWBR04iLY2Zhxgt8tMOPziQUGHBw8aQY/bYts0uj5+9gfHDxxyGOoMD2LUY3E4zOJBwRgKo5Yy5cW5bcrFkzwFmyZnbGCRwapFOMDiQ2AbUwthjIJ3bxpy44UYCGzMvUIsZDi3ys9M/QLQw8xhIW7bVE9bCcDsHagsbW5o0Y9thwloMbucUQPzCw3zYsOfc8cSZPQebgX6RkNyP22EbH3yoqJOTn/+w8cGPsurEfvbmgx8+brPhl2zA4TAUwMgGJkFq8cYkMvhDrMJRMApGwSgYSQAAGnhbVkfVnyIAAAAASUVORK5CYII=","orcid":"","institution":"Taoyuan Hospital, Ministry of Health and Welfare","correspondingAuthor":true,"prefix":"","firstName":"Ching-Hsiao","middleName":"","lastName":"Yu","suffix":""}],"badges":[],"createdAt":"2025-06-12 07:23:42","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6877590/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6877590/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12891-025-09251-1","type":"published","date":"2025-11-04T15:56:56+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":87030715,"identity":"50b63fca-0ede-482a-9f17-c5daa74b6369","added_by":"auto","created_at":"2025-07-18 12:46:13","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":642304,"visible":true,"origin":"","legend":"\u003cp\u003eTwo ipsilateral skin incisions were made over center of trajectory line of upper and lower pedicle under fluoroscope during BE-TLIF procedure; a 1/8 hemovac was placed after wound closure.\u003c/p\u003e","description":"","filename":"FIgure11.png","url":"https://assets-eu.researchsquare.com/files/rs-6877590/v1/93d7243f7e7887e3f1fa450a.png"},{"id":87030718,"identity":"43f6d067-4390-4d21-84ea-76b7dc24d7df","added_by":"auto","created_at":"2025-07-18 12:46:13","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":3216864,"visible":true,"origin":"","legend":"\u003cp\u003eAfter endplate preparation was performed, the cage that filled with autograft bone and demineralized bone matrix was inserted under endoscope under direct view.\u003c/p\u003e","description":"","filename":"Figure21.png","url":"https://assets-eu.researchsquare.com/files/rs-6877590/v1/24e91087ab2ae99764b86ab3.png"},{"id":87030721,"identity":"bce65078-3547-437b-9c8d-c455427f6d40","added_by":"auto","created_at":"2025-07-18 12:46:13","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":6326091,"visible":true,"origin":"","legend":"\u003cp\u003eA 51-year-old with degenerative spondylolisthesis and lumbar spinal stenosis at L3-4 level and received oblique lumbar interbody fusion with lateral screw fixation. No posterior instrumentation or decompression was done. Lumbar spine lateral view (A) and antero-posterior view (B) were taken immediately after the surgery\u003c/p\u003e","description":"","filename":"Figure3A.png","url":"https://assets-eu.researchsquare.com/files/rs-6877590/v1/501509ff1a75693657ebb7ac.png"},{"id":87030724,"identity":"26c048e7-b81c-4495-9515-590c1fa1ca74","added_by":"auto","created_at":"2025-07-18 12:46:13","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":8216793,"visible":true,"origin":"","legend":"\u003cp\u003eA 46-year-old female with degenerative spondylolisthesis at L4-5 level received BE-TLIF and had her segmental lordotic angle and disc height evaluated at L4-L5 on post-operative lumbar spine lateral view image (A). Segmental lordotic angle (SLA) is measured as the angle subtended by the superior endplate line of upper vertebral body and the lower endplate of lower vertebral body. Disc Height (DH) is view as the distance from mid-position of upper endplate to lower endplate of two vertebral body. Cobb angle was measured on post-operative antero-posterior view (B).\u003c/p\u003e","description":"","filename":"Figure4A.png","url":"https://assets-eu.researchsquare.com/files/rs-6877590/v1/39952dc62d8e6466bf4f745a.png"},{"id":95563898,"identity":"5b198244-c907-46aa-9bc2-c17a4998fb60","added_by":"auto","created_at":"2025-11-10 16:01:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":23101238,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6877590/v1/0545d169-dae3-4cd1-8e12-d9fff753d082.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of Midterm Outcomes between Biportal Endoscopic Transforaminal Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion with Lateral Vertebral Body Screw Fixation for Single Level Spondylolisthesis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLumbar spinal fusion is a widely performed surgical procedure aimed at alleviating symptoms associated with degenerative disc disease, spinal stenosis, and other spinal pathologies. Over the years, various surgical approaches have been developed to achieve successful fusion while minimizing surgical morbidity and optimizing clinical outcomes[\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Among these approaches, Oblique lumbar interbody Fusion (OLIF) and transforaminal lumbar interbody fusion have gained popularity for their purported advantages in terms of minimally invasive access and preservation of anatomical structures[\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAlthough minimally invasive TLIF (MIS-TLIF) reduces iatrogenic damage to the paravertebral soft tissues, the technique still requires open incision. With the advancement in endoscopic technique, percutaneous endoscopic technique has been used in not only discectomy but also in spinal decompression and interbody fusion[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The endoscopic transforminal lumbar interbody fusion allows access to the diseased level of the spine for direct decompression and spinal fusion with minimal damage to the surrounding soft tissue, which could potentially improve recovery time and the overall clinical outcome[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. On the other hand, OLIF achieves indirect decompression by accessing lumbar disc through the space between psoas muscle and aorta without disrupting the paravertebral soft tissues and facet joints[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSeveral studies have showed superior clinical outcomes in OLIF compared to MIS-TLIF in mild to moderate lumbar degenerative disease. In Hung et al, the group of OLIF without posterior instrumentation showed significant improvement in post-operative Oswestry Disability Index(ODI) and visual analogue scale (VAS) for back pain compared to the MIS-TLIF group[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Liu et. al demonstrated lower incidence of postoperative low back pain and faster postoperative recovery in the patients received OLIF over the group received MIS-TLIF[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, to author\u0026rsquo;s knowledge, there has been no study that directly compares the Endo-TLIF and OLIF evaluating the clinical and radiographic outcomes. The purpose of this study is aiming to compare the intra-operative, radiographic, and mid-term clinical outcomes between biportal endoscopic TLIF (BE-TLIF) and OLIF in patients with lumbar degenerative disease.\u003c/p\u003e"},{"header":"Material and Method","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy population and surgical techniques\u003c/h2\u003e\u003cp\u003eBetween December 2020 and May 2022, a retrospective review was conducted from the spine department of the two institutions to identify all patients that underwent either OLIF or BE-TLIF procedure. Each surgical technique was performed by either one of the two experienced spine surgeons, and the selection of technique was based on the surgeon’s preference and the accessibility of the working corridor (space between aorta and psoas muscle). All surgical procedures were done in either one of the two orthopedic departments of the institutions. Inclusion criteria were patients with single level degenerative spondylolisthesis (Meyerding grade ≤ 2) and accompanied with either clinical sciatica, neurogenic intermittent claudication, or mechanical low back pain caused by segmental instability. Patients included also received primary single lumbar level surgery between L2 to L5, and had at least 3 years of post-operative follow-up. Exclusion criteria were spinal infection, benign or malignant spinal tumor, multiple level of spinal surgery, revision spinal surgery, incomplete radiographic image, and any patients with less than 3 years of follow-up. The demographic parameters included sex, age, body mass index (BMI), operation time, intra-operative blood loss, days of hospitalization, smoking history, and history of diabetic mellitus. Medical records, laboratory data, radiographic images, and patient reported functional data of these patients were analyzed.\u003c/p\u003e\u003cp\u003e This study received institutional review board approval, and the need to obtain informed patient consent was waived due to the retrospective nature of the study. All procedures performed in this study met with the ethical standards of the national research committee. The data of patients were anonymized and maintained with confidentiality.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eSurgical techniques\u003c/h3\u003e\n\u003cp\u003eEach patient in the BE-TLIF group received biportal endoscopic transforaminal lumbar interbody fusion using the method from Yu et. al.[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The patient received intubated general anesthesia and was placed in prone position. Two ipsilateral skin incisions were made over center of trajectory line of upper and lower pedicle under fluoroscope (Fig.\u0026nbsp;1). The direction of the approach was chosen depending on which side of the patient’s symptom was more severe. The incision wounds were used for screws and scope entrance. Muscles were gently detached from the lamina surface using periosteal elevator. The scope was inserted via working portal and a radiorequency probe was inserted via working portal, which formed triangulation of biportal endoscope was established. Discectomy and laminotomy were done. Bilateral decompression was performed by over the top approach in every patient. After endplate preparation, a 10-12mm polyetheretherketone (PEEK) bullet-shaped cage that filled with autograft bone and demineralized bone matrix was inserted (Fig.\u0026nbsp;2). Percutaneous pedicle screws insertion was then applied via the previously incised skin portals. Finally a Hemovac drain was inserted via one of the incision wound (Fig.\u0026nbsp;1).\u003c/p\u003e\u003cp\u003eFor the OLIF group, anterolateral OLIF procedure was done by making an incision around 4cm ventral to the anterior border of the desired intervertebral disc. Blunt dissection through lateral abdominal muscles was done to approach the disc space in the oblique corridor. Mild retraction was done on the psoas muscle. The ORACLE cage (Depuy Company) that filled with cancellous allopathic bone graft was inserted. The cage size larger than pre-operative disc height was chosen for the purpose of augmentation in neuroforamen. The spinal indirect decompression was achieved by cage insertion without laminectomy or posterior instrumentation and lateral vertebral body fixation with pedicle screws was then used for cage fixation (Fig.\u0026nbsp;3A-B).\u003c/p\u003e\n\u003ch3\u003eRadiography\u003c/h3\u003e\n\u003cp\u003eDefinite diagnosis of each patient was confirmed via pre-operative magnetic resonance imaging (MRI) and plain film. Postoperative radiographic images were taken at postoperative day 1, 1 month, 3 months, 6 months and then every year. Segmental lordotic angle (SLA), disc height (DH), cage subsidence (CS), screws halo sign, and coronal tilting angle (CTA) were recorded by two investigators and rechecked by the other two investigators. SLA was recorded using lateral view of lumbar spine X-ray image by measuring the angle between upper end plate of vertebral body to lower endplate of lower vertebral body (Fig.\u0026nbsp;4A). Disc height was measured as the distance from mid-position of upper endplate to lower endplate of two vertebral body. CTA was evaluated by measuring the Cobb angle of lumbar antero-posterior view on the X-ray (Fig.\u0026nbsp;4B). The evaluations for Halo sign and CS were assessed 6 months post-operatively. CS was defined as cage migration greater than 2-mm under X-ray. The presence of trabeculae bridging between the vertebral endplate and cage without gap under the X-ray signified the occurrence of complete spine fusion.\u003c/p\u003e\n\u003ch3\u003eClinical functioning\u003c/h3\u003e\n\u003cp\u003eClinical functional outcomes were evaluated using VAS and ODI. The evaluations and data collection were done during pre-operation, 3 days after operation, and most recent follow-up. All procedures performed in this study were met with the ethical standards of the national research committee.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eStatistical calculations were performed using SPSS 27.0 to analyze the parameters in both groups of patients. All quantitative variables were presented as mean standard deviation, and qualitative variables were shown in terms of ratio and number. Continuous variables were evaluated by independent t-test. The categorical variables were performed by Chi-square test. A P value \u0026lt; 0.05 was considered to be statistically significance.\u003c/p\u003e\u003c/div\u003e"},{"header":"Result","content":"\u003cp\u003eBetween December 2020 and September 2022, a total of 40 patients that underwent OLIF and 32 patients that received BE-TLIF in the spine department of the two institutions were enrolled. For a total of 40 OLIF patients, 6 of them were excluded from this study due to loss of follow-ups, multiple level of lumbar surgery, history of surgery at the lumbar level, or incomplete radiographic data. Among the 32 BE-TLIF patients, 2 of them were excluded because the surgical site involved sacral (S1) level. After the screening, 34 OLIF patients (12 females, 22 males) and 30 BE-TLIF patients (13 females, 17 males) were enrolled in this study.\u003c/p\u003e\u003cp\u003eThe demographics for OLIF and BE-TLIF groups were comparatively matched. The mean ages for OLIF and the BE-TLIF were 60.3 years old and 58.4 years old, respectively (p = 0.618). The mean BMI for OLIF was 27.2 kg/m\u003csup\u003e2\u003c/sup\u003e and BE-TLIF patients had an average of 24.9 kg/m\u003csup\u003e2\u003c/sup\u003e (p = 0.594). Three patients in the OLIF group had smoking history while the BE-TLIF group had 2 (p = 0.679). Among the OLIF group, 6 patients from the OLIF group had history of diabetes mellitus while the BE-TLIF group had 4 (p = 0.5.95). The average follow-up for BE-TLIF was 40 months and 43 months for OLIF (p = 0.727) (Table. 1).\u003c/p\u003e\u003cp\u003eThe mean operation time for OLIF was significantly shorter than that of BE-TLIF (136.5 ± 34.84 vs 188.5 ± 32.56, p = 0.002). The patients received OLIF procedure had an average of 5.38 days of hospitalization compared to 5.01 days of the BE-TLIF patients (p = 0.687). Blood loss during operation was also significantly less in the BE-TLIF compared to the OLIF (32.33 ± 30.11 ml vs 108.5 ± 27.02 ml, p \u0026lt; 0.001) (Table. 2).\u003c/p\u003e\u003ch3\u003eRadiographic Outcomes\u003c/h3\u003e\u003cp\u003eThe segmental lordotic angle (SLA) increased from a mean of 13.21 preoperatively to 15.61 postoperatively in the OLIF group and the BE-TLIF group went from a mean of 10.59 preoperatively to 11.13postoperatively (Table. 3). The immediate SLA change between the BE-TLIF group and OLIF group was significantly different (0.54 ± 0.39 vs 2.40 ± 2.29, respectively, p = 0.041). The follow-up SLA change in the OLIF and BE-TLIF groups (2.69 ± 1.54 vs -0.22 ± 0.89, respectively, p \u0026lt; 0.001) showed significant difference. The CTA for the OLIF group was 6.57 ± 5.42 preoperatively, 2.88 ± 2.55 postoperatively, and 3.75 ± 4.05 follow-up; BE-TLIF group had CTA of 5.94 ± 4.76 preoperatively, 2.74 ± 1.99 postoperatively, and 2.30 ± 2.56 follow-up. No significant difference was noted in post-operative and follow-up CTA change (CTAC) between the 2 groups (p = 0.512, 0.481, respectively). The pre-operative DH was 7.51 ± 1.33 millimeter in the OLIF group and 6.54 ± 1.56 millimeter in the Endo-TLIF group (p = 0.112). The post-operative disc height improved in OLIF and BE-TLIF groups (10.39 ± 1.25 vs 9.44 ± 1.59, p = 0.347) and the follow-up DH decreased slightly in both group (9.48 ± 1.04 vs 8.29 ± 1.45, p = 0.214). Both the immediate DH change and follow up DH change between the 2 groups showed no significant difference (p = 0.402, 0.385, respectively). Lastly, CS and screws halo sign were noted in 8 out of 34 OLIF patients and 6 out of 30 BE-TLIF patients (p = 0.531). The fusion rate at 12th month for BE-TLIF was 73.3% (24 out of 30) and 73.5% (25 out of 34) for OLIF (p = 0.811); The fusion rate at 24th month for BE-TLIF was 93.3% (28 out of 30) and 91.2% (31 out of 34) for OLIF (p = 0.791)\u003c/p\u003e\u003ch3\u003eFunctional Outcomes\u003c/h3\u003e\u003cp\u003eThe mean pre-operative VAS back pain scores were similar between the OLIF group and the BE-TLIF group (6.53 ± 1.14 vs 6.01 ± 1.52, p = 0.654) (Table.2). The post-operative back pain (3 days after surgery) scores were 0.94 ± 0.91 for the OLIF patients and 2.61 ± 1.67 for the BE-TLIF patients, and the difference was significant (p = 0.035). There was no significant difference in back pain score between the OLIF group and the BE-TLIF group for the most recent follow up (0.63 ± 0.47 vs 0.72 ± 0.59, p = 0.336). Pre-operative leg pain scores for the OLIF group and BE-TLIF group were 6.37 ± 1.11 and 6.92 ± 1.21, respectively (p = 0.395); post-operative leg pain scores (3 days after the surgery) were 0.77 ± 0.73 and 0.87 ± 0.74 (p = 0.776). The preoperative ODI’s were comparable between the 2 groups (OLIF: 60.09 ± 5.99, BE-TLIF: 64.2 ± 13.81, p = 0.403); the follow-up ODI’s were 22.79 ± 9.42 for OLIF and 27.99 ± 14.32 for BE-TLIF (p = 0.265). The ODI improvement 6 months after surgery between the 2 groups showed no significant difference (OLIF: 37.30 ± 8.77, BE-TLIF: 36.21 ± 8.91, p = 0.784). There were 4 patients from the BE-TLIF with intermittent claudication 1 month after the operation, and 5 patients from the OLIF group showed the symptom (p = 0.807),\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe lumbar interbody fusion options for degenerative lumbar spinal stenosis are categorized into two main types: direct decompression and indirect decompression. Direct decompression involves a posterior-only approach to remove bone spurs, ligament, cyst, or disc material causing nerve impingement, followed by instrumented fusion using screws and an interbody technique such as TLIF[\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Indirect decompression, on the other hand, involve inserting a large interbody device through an abdominal approach[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. This method restores disc height and spinal canal dimensions by stretching the ligaments, thereby relieving nerve root impingement without removing any posterior osteoligamentous complex.\u003c/p\u003e\u003cp\u003eRecent studies have compared the clinical outcomes between direct decompression and indirect decompression of lumbar interbody fusion. Koike et al. compared OLIF with lateral screw fixation and MIS-TLIF in patients received single level lumbar interbody fusion, and while both groups showed postoperative improvements in the clinical outcome scores of all Japanese orthopaedic association back pain evaluation questionnaire (JOABPEQ) domains, the OLIF group showed significant higher rate increase in the psychological domain compared to the MIS-TLIF[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Lin et al. demonstrated that OLIF was superior in time of fusion, restoration of disc height, intraoperative blood loss, and surgery time[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. However, there are instances where direct decompression is preferred over indirect decompression of lumbar interbody fusion, such as revision spine surgery, less discrepancy of the disc height on postural change, and surgical corridor access not available[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In our study, the BE-TLIF showed similar post-operative clinical outcomes compared to the OLIF except immediate post-operative back pain and segmental lordotic angle improvement. However, by minimizing the iatrogenic damage to the paraspinal soft tissue and with significantly less intraoperative blood loss (demonstrated in our study) using endoscopic technique, the BE-TLIF was able to provide similar clinical midterm outcomes compared to OLIF\u003c/p\u003e\u003cp\u003eEndplate injury is considered as a detrimental factor for cage subsidence[\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. In Calek et. al., weakening of the endplate during the endplate preparation via rasping significantly reduces the axial endplate resistance to subsidence by 15% in the patients received TLIF[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. In a systemic review by Parisien et. al., the cage subsidence of TLIF was higher than that of OLIF[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. However, our result demonstrated that the rate of cage subsidence was comparable between the BE-TLIF group and the OLIF group. Cage subsidence rate could be reduced if endplate injury was minimized and thoroughly prepared. In our study, the endoscope was able to reach near the annulotomy site and the disc space was visually seen and cleaned using radiofrequency probe. By using the endoscopic technique, the chance of bony endplate injury could be reduced.\u003c/p\u003e\u003cp\u003eNeurogenic intermittent claudication is the most common symptom associated with lumbar spinal canal stenosis. In Morishita et al., the increase in changes of local pressure of the intervertebral foramen was significantly associated with the severity of post-operative intermittent claudication in patients with decompression of spinal canal[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. The study further suggested that dynamic mechanical stress on the lumbar spinal nerve roots, rather than static mechanical stress associated with different postures or nerve root ischemia, may be the primary cause. Zhu et al. stated that OLIF was found to be effective for dynamic radicular pain, which is mostly relieved during rest[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In our study, the percentage of patients with post-operative intermittent claudication was lower in the BE-TLIF (13.3%) compared to OLIF (14.7%), although the difference was not statistically significant. While dynamic mechanical stress on the spine nerve roots may be the primary cause for intermittent claudication, the static mechanical stress on the lumbar nerve roots couldn\u0026rsquo;t be completely relieved by OLIF. BE-TLIF, on the other hand, was able to achieve direct decompression. Our result was consistent with the studies mentioned above.\u003c/p\u003e\u003cp\u003eA recent study found that the rate of dysesthesia in Endo-TLIF was higher compared to standard uniportal endoscopic procedures, likely due to the larger outer diameter of the Endo-TLIF cannula (14\u0026ndash;16 mm) and the strong vibrations experienced during cannula placement and expandable cage insertion[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Additionally, several studies have indicated that during endoscopy-guided interbody cage placement, smaller fusion cages had to be used because conventional cages were too large to pass through the working portal[\u003cspan additionalcitationids=\"CR33 CR34\" citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. As a result, some surgeons preferred biportal endoscopic technique. Xie et al. stated that compared with unilateral portal lumbar interbody fusion, biportal lumbar interbody fusion had shorter operative time and a higher fusion rate[\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. Biportal technique offers wider vision of surgical site, greater maneuverability of instruments, more cage size selection, and more efficient decompression range. We chose facetectomy instead of the biportal trans-Kambin approach performed in other recent studies[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. Although the facet joint was not spared, we limited the disruption of the nerve roots caused by cannula insertion. Only two patient reported post-operative transient dysesthesia in our study, and the symptom resolved within 3 months after the operation. Despite high learning curve and technically demanding (significantly longer operation time in BE-TLIF compared to OLIF from our study), the biportal endoscopic technique offers direct inspection to the site. The risk of neural element injury is reduced by using nerve retractor to retract the dura gently through the working portal when inserting the inter-body cage.\u003c/p\u003e\u003cp\u003eThere are some limitations in our study. First of all, this was a retrospective study with small sample size in each group. Secondly, although this was a multi-centers study, the overall samples were not randomized, which may have led to selection bias. In addition, some data such as bone mass density and follow-up computer tomography were not available in each patient, which could\u0026rsquo;ve provided some additional insight regarding cage subsidence and fusion rate. Lastly, the follow-up period was relatively short. The larger prospective studies in the future are needed to confirm the clinical outcomes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, the endoscopic lumbar interbody fusion is becoming popular surgical techniques for the treatment of lumbar degenerative disease, offering significant improvements in radiographic parameters and clinical outcomes. While OLIF still offers superior results in restoration of lumbar lordotic angle and short term post-operative back pain, the use of endoscopic technique in BE-TLIF could potentially achieve comparable radiographic and clinical outcomes in cage subsidence rate and follow-up VAS back/leg pain compared to the indirect decompression of OLIF. However, larger prospective studies in the future are needed to confirm the long term clinical outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eThis study was approved by the Institutional Review Board (IRB) of Ministry of Health and Welfare Taoyuan General Hospital and Chang Gung Medical Foundation (IRB approval number: TYGH 113001; 202401613B0). The need to obtain informed patient consent was waived due to the retrospective nature of the study. All procedures performed in this study met with 1964 Declaration of Helsinki and the ethical standards of the national research committee. The data of patients were anonymized and maintained with confidentiality.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman Ethics and Consent to Participate declarations:\u003c/strong\u003e not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003enot applicable due to restrospective study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData sharing\u003c/strong\u003e: not applicable to this article as no datasets were generated or analysed during the current study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number:\u003c/strong\u003e not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe data of patients were anonymized and maintained with confidentiality.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u003c/strong\u003e Each author certifies that he has no commercial associations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNone\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest:\u003c/strong\u003e Each author certifies that he has no commercial associations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclosure of Funding:\u003c/strong\u003e None.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003e CH Yu contributed to the study conception and design. SH Hung performed the data collection and analysis. SH Hung and FC Kao contributed equally to this manuscript draft. All authors critically reviewed the manuscript for important intellectual content. All authors approved the final version of the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMobbs RJ, Phan K, Malham G, Seex K, Rao PJ. Lumbar interbody fusion: techniques, indications and comparison of interbody fusion options including PLIF, TLIF, MI-TLIF, OLIF/ATP, LLIF and ALIF. J Spine Surg. 2015;1(1):2\u0026ndash;18.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFoley KT, Holly LT, Schwender JD. Minimally invasive lumbar fusion. Spine. 2003;28(15S):S26\u0026ndash;35.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePark Y, Ha JW. Comparison of one-level posterior lumbar interbody fusion performed with a minimally invasive approach or a traditional open approach. Spine. 2007;32(5):537\u0026ndash;43.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBagby GW. Arthrodesis by the distraction-compression method using a stainless steel implant. In., vol. 11: SLACK Incorporated Thorofare, NJ; 1988: 931\u0026ndash;934.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhu HF, Fang XQ, Zhao FD, Zhang JF, Zhao X, Hu ZJ, Fan SW. Comparison of Oblique Lateral Interbody Fusion (OLIF) and Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) for Treatment of Lumbar Degeneration Disease: A Prospective Cohort Study. Spine (Phila Pa 1976). 2022;47(6):E233\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYang J, Liu C, Hai Y, Yin P, Zhou L, Zhang Y, Pan A, Zhang Y, Zhang L, Ding Y et al. Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Spinal Stenosis: Preliminary Report of Seven Cases with 12-Month Follow-Up. \u003cem\u003eBiomed Res Int\u003c/em\u003e 2019, 2019:3091459.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePeng CWB, Yue WM, Poh SY, Yeo W, Tan SB. Clinical and radiological outcomes of minimally invasive versus open transforaminal lumbar interbody fusion. Spine. 2009;34(13):1385\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWang MY, Grossman J. Endoscopic minimally invasive transforaminal interbody fusion without general anesthesia: initial clinical experience with 1-year follow-up. NeuroSurg Focus. 2016;40(2):E13.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJacquot F, Gastambide D. Percutaneous endoscopic transforaminal lumbar interbody fusion: is it worth it? Int Orthop. 2013;37:1507\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLee CK, Park JY, Zhang HY. Minimally invasive transforaminal lumbar interbody fusion using a single interbody cage and a tubular retraction system: technical tips, and perioperative, radiologic and clinical outcomes. J Korean Neurosurg Soc. 2010;48(3):219\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhou Y, Zhang C, Wang J, Chu T-w, Li C-q, Zhang Z-f. Zheng W-j: Endoscopic transforaminal lumbar decompression, interbody fusion and pedicle screw fixation\u0026mdash;\u0026mdash;a report of 42 cases. Chin J Traumatol. 2008;11(04):225\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHeo DH, Choi WS, Park C-K, Kim J-S. Minimally Invasive Oblique Lumbar Interbody Fusion with Spinal Endoscope Assistance: Technical Note. World Neurosurg. 2016;96:530\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHung S-F, Liao J-C, Tsai T-T, Li Y-D, Chiu P-Y, Hsieh M-K, Kao F-C. Comparison of outcomes between indirect decompression of oblique lumbar interbody fusion and MIS-TLIF in one single-level lumbar spondylosis. Sci Rep. 2021;11(1):12783.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu L, Xue H, Han Z, Jiang L, Chen L, Wang D. Comparison between OLIF and MISTLIF in degenerative lumbar stenosis: an age-, sex-, and segment-matched cohort study. Sci Rep. 2023;13(1):13188.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYu C-H, Wu H-K. Biportal Endoscopic Transforaminal Lumbar Interbody Fusion with Percutaneous Instrumentation: A Technical Note. J Minim Invasive Spine Surg Tech 2024, 0.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFormica M, Quarto E, Zanirato A, Mosconi L, Vallerga D, Zotta I, Baracchini ML, Formica C, Felli L. Lateral Lumbar Interbody Fusion: What Is the Evidence of Indirect Neural Decompression? A Systematic Review of the Literature. Hss j. 2020;16(2):143\u0026ndash;54.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFujibayashi S, Hynes RA, Otsuki B, Kimura H, Takemoto M, Matsuda S. Effect of indirect neural decompression through oblique lateral interbody fusion for degenerative lumbar disease. Spine (Phila Pa 1976). 2015;40(3):E175\u0026ndash;182.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKepler CK, Sharma AK, Huang RC, Meredith DS, Girardi FP, Cammisa FP Jr., Sama AA. Indirect foraminal decompression after lateral transpsoas interbody fusion. J Neurosurg Spine. 2012;16(4):329\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMalham GM, Parker RM, Goss B, Blecher CM. Clinical results and limitations of indirect decompression in spinal stenosis with laterally implanted interbody cages: results from a prospective cohort study. Eur Spine J. 2015;24(Suppl 3):339\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOzgur BM, Aryan HE, Pimenta L, Taylor WR. Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion. Spine J. 2006;6(4):435\u0026ndash;43.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKoike Y, Kotani Y, Terao H, Iwasaki N. Comparison of Outcomes of Oblique Lateral Interbody Fusion with Percutaneous Posterior Fixation in Lateral Position and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis. Asian Spine J. 2021;15(1):97\u0026ndash;106.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLin GX, Akbary K, Kotheeranurak V, Quillo-Olvera J, Jo HJ, Yang XW, Mahatthanatrakul A, Kim JS. Clinical and Radiologic Outcomes of Direct Versus Indirect Decompression with Lumbar Interbody Fusion: A Matched-Pair Comparison Analysis. World Neurosurg. 2018;119:e898\u0026ndash;909.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYingsakmongkol W, Jitpakdee K, Kerr S, Limthongkul W, Kotheeranurak V, Singhatanadgige W. Successful Criteria for Indirect Decompression With Lateral Lumbar Interbody Fusion. Neurospine. 2022;19(3):805\u0026ndash;15.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLimthongkul W, Praisarnti P, Tanasansomboon T, Prasertkul N, Kotheeranurak V, Yingsakmongkol W, Singhatanadgige W. An Expanded Surgical Corridor of Oblique Lateral Interbody Fusion at L4-5: A Magnetic Resonance Imaging Study. Neurospine. 2023;20(4):1450\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSinghatanadgige W, Sukthuayat A, Tanaviriyachai T, Kongtharvonskul J, Tanasansomboon T, Kerr SJ, Limthongkul W. Risk factors for polyetheretherketone cage subsidence following minimally invasive transforaminal lumbar interbody fusion. Acta Neurochir (Wien). 2021;163(9):2557\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWu H, Shan Z, Zhao F, Cheung JPY. Poor Bone Quality, Multilevel Surgery, and Narrow and Tall Cages Are Associated with Intraoperative Endplate Injuries and Late-onset Cage Subsidence in Lateral Lumbar Interbody Fusion: A Systematic Review. Clin Orthop Relat Res. 2022;480(1):163\u0026ndash;88.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhou ZJ, Xia P, Zhao FD, Fang XQ, Fan SW, Zhang JF. Endplate injury as a risk factor for cage retropulsion following transforaminal lumbar interbody fusion: An analysis of 1052 cases. Med (Baltim). 2021;100(5):e24005.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCalek A-K, Cornaz F, Suter M, Fasser M-R, Farshad M, Widmer J. Endplate weakening during cage bed preparation significantly reduces endplate load capacity. Eur Spine J. 2024;33(7):2621\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eParisien A, Wai EK, ElSayed MSA, Frei H. Subsidence of Spinal Fusion Cages: A Systematic Review. Int J Spine Surg. 2022;16(6):1103\u0026ndash;18.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMorishita Y, Hida S, Naito M, Arimizu J, Takamori Y. Neurogenic Intermittent Claudication in Lumbar Spinal Canal Stenosis: The Clinical Relationship Between the Local Pressure of the Intervertebral Foramen and the Clinical Findings in Lumbar Spinal Canal Stenosis. Clin Spine Surg. 2009;22(2):130\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMorgenstern C, Yue JJ, Morgenstern R. Full percutaneous transforaminal lumbar interbody fusion using the facet-sparing, trans-kambin approach. Clin Spine Surg. 2020;33(1):40\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAhn Y, Youn MS, Heo DH. Endoscopic transforaminal lumbar interbody fusion: a comprehensive review. Expert Rev Med Dev. 2019;16(5):373\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhang Y-W, Xia W-H, Gao W-C, Xiao X, Xiao Y, Gong F-P. Direct foraminoplasty in endoscope-assisted transforaminal lumbar interbody fusion for the treatment of lumbar disc herniation. J Int Med Res. 2020;48(1):0300060519875372.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHwa Eum J, Hwa Heo D, Son SK, Park CK. Percutaneous biportal endoscopic decompression for lumbar spinal stenosis: a technical note and preliminary clinical results. J Neurosurg Spine. 2016;24(4):602\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHeo DH, Son SK, Eum JH, Park CK. Fully endoscopic lumbar interbody fusion using a percutaneous unilateral biportal endoscopic technique: technical note and preliminary clinical results. Neurosurg Focus. 2017;43(2):E8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eXie YZ, Shi Y, Zhou Q, Feng CQ, Zhou Y, Li T, Yu Y, Fan XH. Comparison of the safety and efficacy of unilateral biportal endoscopic lumbar interbody fusion and uniportal endoscopic lumbar interbody fusion: a 1-year follow-up. J Orthop Surg Res. 2022;17(1):360.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKuo K-P, Choi D-J. Biportal Endoscopic Trans-Kambin Lumbar Interbody Fusion: Surgical Techniques and Treatment Outcomes. J Minim Invasive Spine Surg Tech. 2024;9(Suppl 1):S24\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eTable 1. Demographic parameters\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; BE-TLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eOLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eNumber of patients\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e58.4\u0026plusmn;10.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e60.3\u0026plusmn;11.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.618\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eSex (Male: Female)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e17:13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e22:12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.723\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eSmoker\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.679\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e24.9\u0026plusmn;3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e27.2\u0026plusmn;5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.594\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eDiabetes Mellitus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.595\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eMean F/U (months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.727\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eHerniated Intervertebral Disc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.599\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eLumbar Spinal Stenosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.601\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eSurgery Level\u003c/p\u003e\n \u003cp\u003e-L2/3\u003c/p\u003e\n \u003cp\u003e-L3/4\u003c/p\u003e\n \u003cp\u003e-L4/5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.679\u003c/p\u003e\n \u003cp\u003e0.416\u003c/p\u003e\n \u003cp\u003e0.515\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eValues are mean\u0026plusmn; standard deviation\u003c/p\u003e\n \u003cp\u003eOLIF: oblique lateral lumbar interbody fusion\u003c/p\u003e\n \u003cp\u003eBE-TLIF: Percutaneous biportal endoscopic transforaminal lumbar interbody fusion\u003c/p\u003e\n \u003cp\u003eBMI: body mass index\u003c/p\u003e\n \u003cp\u003eF/U: follow-up\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e*: p\u0026lt;0.05, statistical significance\u003c/p\u003e\n \u003cp\u003eDiabetes Mellitus: either type 1 or type 2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eTable 2. Perioperative and clinical outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;BE-TLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eOLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eBlood loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e32.33\u0026plusmn;30.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e108.50\u0026plusmn;27.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e*\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eOperation time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e188.50\u0026plusmn;32.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e136.50\u0026plusmn;34.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e*0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eDays of hospitalization\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e5.01\u0026plusmn;1.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e5.19\u0026plusmn;4.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.687\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ePre VAS back pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e6.01\u0026plusmn;1.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e6.53\u0026plusmn;1.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.654\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ePost VAS back pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e2.61\u0026plusmn;1.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.94\u0026plusmn;0.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e*0.035\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eF/U VAS back pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.72\u0026plusmn;0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.63\u0026plusmn;0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.336\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ePre VAS leg pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e6.92\u0026plusmn;1.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e6.37\u0026plusmn;1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.395\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ePost VAS leg pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.87\u0026plusmn;0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.77\u0026plusmn;0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.776\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003ePre ODI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e64.2\u0026plusmn;12.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e60.09\u0026plusmn;5.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.403\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eFollow-up ODI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e27.99\u0026plusmn;14.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e22.79\u0026plusmn;9.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.265\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eODI improvement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e36.21\u0026plusmn;8.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e37.30\u0026plusmn;8.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eClaudication (pre)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.742\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003eClaudication (post)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 156px;\"\u003e\n \u003cp\u003e0.807\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eValues are mean\u0026plusmn; standard deviation\u003c/p\u003e\n \u003cp\u003eODI: Oswestry Disability Index\u003c/p\u003e\n \u003cp\u003eVAS: visual analogue scale\u003c/p\u003e\n \u003cp\u003ePost: post-operative\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eF/U: most recent follow-up\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eClaudication (post): intermittent claudication (1 month after surgery)\u003c/p\u003e\n \u003cp\u003e*: p\u0026lt;0.05, statistical significance\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eTable 3. Radiographic outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 315px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; BE-TLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003eOLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePre SLA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e10.59\u0026plusmn;8.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e13.21\u0026plusmn;6.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.502\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost SLA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e11.13\u0026plusmn;7.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e15.61\u0026plusmn;7.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.115\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U SLA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e10.91\u0026plusmn;5.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e15.9\u0026plusmn;7.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.127\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost SLA change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e0.54\u0026plusmn;0.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e2.40\u0026plusmn;2.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e*0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U SLA change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e-0.22\u0026plusmn;0.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e2.69\u0026plusmn;1.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e*\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePre CTA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e5.94\u0026plusmn;4.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e6.57\u0026plusmn;5.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.495\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost CTA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e2.74\u0026plusmn;1.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e2.88\u0026plusmn;2.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.512\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U CTA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e2.30\u0026plusmn;2.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e3.75\u0026plusmn;4.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.192\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost CTA change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e-3.20\u0026plusmn;1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e-3.69\u0026plusmn;3.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.481\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U CTA change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e-2.95\u0026plusmn;1.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e-2.82\u0026plusmn;2.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.133\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePre disc height\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e6.54\u0026plusmn;1.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e7.51\u0026plusmn;1.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.112\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost disc height\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e9.44\u0026plusmn;1.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e10.39\u0026plusmn;1.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.347\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U disc height\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e8.29\u0026plusmn;1.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e9.48\u0026plusmn;1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.214\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003ePost disc height change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e2.90\u0026plusmn;1.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e3.28\u0026plusmn;1.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.402\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 192px;\"\u003e\n \u003cp\u003eF/U disc height change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.75\u0026plusmn;1.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e1.97\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.385\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003ePost cage subsidence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.531\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003ePost halo sign\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.531\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003eFusion rate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eComplete (12 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.811\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eIncomplete (12 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eComplete (24 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e0.791\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eIncomplete (24 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 154px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003eValues are mean\u0026plusmn; standard deviation\u003c/p\u003e\n \u003cp\u003eSLA: segmental lordotic angle\u003c/p\u003e\n \u003cp\u003eCTA: coronal tilting angle\u003c/p\u003e\n \u003cp\u003ePost: post-operative (3 days after surgery)\u003c/p\u003e\n \u003cp\u003eF/U: most recent follow-up\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e*: p\u0026lt;0.05, statistical significance\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"biportal endoscopic lumbar interbody fusion, indirect decompression, oblique lumbar interbody fusion, spondylolisthesis","lastPublishedDoi":"10.21203/rs.3.rs-6877590/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6877590/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eThe purpose of this study is aiming to compare the intra-operative, radiographic, and mid-term clinical outcomes between direct decompression of BE-TLIF and indirect decompression of OLIF in patients with single level spondylolisthesis\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod: \u003c/strong\u003eBetween December 2020 and May 2022, patients with single level spondylolisthesis and received either OLIF or BE-TLIF from the authors’ orthopedic departments were selected to enroll in this retrospective study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eA total of 34 patients that underwent single-level OLIF and 30 patients that received single-level BE-TLIF in the spine department of our institutions were included. Both groups had similar demographic parameters. BE-TLIF showed significantly less blood loss compared to that of OLIF (p\u0026lt;0.001). The OLIF group yielded shorter operation time than the BE-TLIF group (p=0.002). The improvement in restoration of follow-up segmental lordosis was significantly more in OLIF group than BE-TLIF group (p\u0026lt;0.001). The OLIF group was significantly better in post-operative VAS back pain (p=0.035). The cage subsidence rates between the two groups were not significantly different. The follow-up Oswestry Disability Index (ODI) and overall visual analogue scale were comparable between the 2 groups without significant difference.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eWhile OLIF still offers superior results in restoration of lumbar lordotic angle and short term post-operative back pain, the use of endoscopic technique in BE-TLIF may achieve comparable radiographic and clinical outcomes in cage subsidence rate and follow-up VAS back/leg pain compared to the indirect decompression of OLIF.\u003c/p\u003e","manuscriptTitle":"Comparison of Midterm Outcomes between Biportal Endoscopic Transforaminal Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion with Lateral Vertebral Body Screw Fixation for Single Level Spondylolisthesis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-18 12:46:08","doi":"10.21203/rs.3.rs-6877590/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-15T04:23:57+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-12T08:51:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"174505408843040241611895140903463490476","date":"2025-09-06T08:02:53+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-28T13:13:27+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-19T08:39:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"153124662403851917400780019109399125485","date":"2025-07-17T06:33:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"74181600854351510063950445152633241519","date":"2025-07-13T23:42:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"191409449612205294907815223922073230273","date":"2025-07-12T06:47:16+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-11T16:47:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-09T06:13:22+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-06-18T04:37:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-17T11:24:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Musculoskeletal Disorders","date":"2025-06-17T11:21:28+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ffaa834d-cdeb-43b7-b8d6-3a86d714af51","owner":[],"postedDate":"July 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-10T15:58:41+00:00","versionOfRecord":{"articleIdentity":"rs-6877590","link":"https://doi.org/10.1186/s12891-025-09251-1","journal":{"identity":"bmc-musculoskeletal-disorders","isVorOnly":false,"title":"BMC Musculoskeletal Disorders"},"publishedOn":"2025-11-04 15:56:56","publishedOnDateReadable":"November 4th, 2025"},"versionCreatedAt":"2025-07-18 12:46:08","video":"","vorDoi":"10.1186/s12891-025-09251-1","vorDoiUrl":"https://doi.org/10.1186/s12891-025-09251-1","workflowStages":[]},"version":"v1","identity":"rs-6877590","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6877590","identity":"rs-6877590","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}