OBJECTIVE: To investigate the improvement of spinopelvic parameters and therapeutic efficacy in the treatment of complex degenerative lumbar spondylolisthesis (CDLS) after oblique lumbar interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF).
METHODS: From January 2018 to December 2020, 71 patients with CDLS underwent OLIF or TLIF at the same hospital: 31 in the OLIF group and 40 in the TLIF group. The spinopelvic parameters, perioperative data, and clinical outcomes were elected and compared between the 2 groups.
RESULTS: There were no statistic differences in demographic perioperative complication rates and preoperative spinopelvic parameters between the two groups. OLIF group showed lower serum C-reactive protein in the early postoperative stage, shorter length of stay, less estimated blood loss and larger slippage correction rate (88.05 vs. 62.37%) (all P ＜ 0.05). There was no significant difference in the visual analog scale and Oswestry disability index scores before operation and three and six months after surgery, but OLIF group was better in the long-term with visual analog scale and Oswestry disability index (1.7/13.2 vs. 2.3/16.5). And it was significantly different in the lumbar lordosis angle, segmental lordosis angle, pelvic tilt, sacral slope (46.0°/9.3°/18.2°/35.9° vs. 40.4°/7.2°/23.9°/31.1°), and sagittal vertical axis (21.6 vs. 31.7mm) after surgery between OLIF and TLIF groups (all P ＜ 0.05).
CONCLUSIONS: In the therapy of CDLS, OLIF can better reduce pelvic tilt, L1 axis S1 distance, and sagittal vertical axis, and increase lumbar lordosis angle and sacral slope, showing advantages over TLIF in improving and maintaining spinopelvic parameters. Although there was no difference in complication rates between OLIF and TLIF, OLIF was more minimally invasive, had less tissue damage, had faster recovery, and had better long-term outcomes.

UNASSIGNED: Managing adult degenerative lumbar scoliosis (ADLS) presents a complex challenge, requiring advanced, minimally invasive surgical techniques.
UNASSIGNED: This study aims to evaluate and compare the efficacy and outcomes of oblique lateral interbody fusion (OLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in treating ADLS, with an emphasis on surgical methods, recovery times, and spinal correction results.
UNASSIGNED: We reviewed 42 patients with ADLS who did not respond to conservative treatments. These patients underwent either OLIF or MIS-TLIF procedures. Key factors analyzed included surgical duration, blood loss, complications, and changes in preoperative and postoperative lumbar lordosis (LL), anterior and posterior disc height (ADH, PDH), and Cobb angles. Statistical analysis was conducted using SPSS software, with significance determined at p < 0.05.
UNASSIGNED: The OLIF technique showed notable benefits in multi-segment spinal corrections, particularly in enhancing intervertebral disc height and correcting Cobb angles. While both surgical methods effectively addressed spinal deformities, OLIF was less invasive, resulting in reduced blood loss, shorter surgery times, and fewer complications. No significant differences were found between the two techniques for single-segment corrections.
UNASSIGNED: For multi-segment spinal corrections in ADLS, OLIF is a superior choice due to its minimal invasiveness and favorable recovery profile. However, for patients with primarily radicular symptoms and no significant postural alterations, MIS-TLIF may be more appropriate.

BACKGROUND: Cage subsidence is a common complication after lumbar interbody fusion surgery, with low bone mineral density (BMD) being a significant risk factor. ໿Endplate bone quality (EBQ) obtained from clinical MRI scans has been deemed reliable in determining regional BMD. However, the association between EBQ score and cage subsidence following oblique lumbar interbody fusion (OLIF) has not been clearly established.
OBJECTIVE: This study aims to assess the relationship between EBQ score and cage subsidence in patients who underwent single-level OLIF.
METHODS: A retrospective study.
METHODS: The study included adults with degenerative spinal conditions who underwent single-level OLIF at our institution.
METHODS: Cage subsidence, disc height, EBQ score, fusion rate.
METHODS: This retrospective study analyzed data from patients who underwent single-level OLIF surgery at our institution between October 2017 and August 2022. Postoperative CT scans were used to measure cage subsidence, while the EBQ score was calculated using preoperative non-contrast T1-weighted MRI. To determine the predictive ability of the EBQ score, receiver operating characteristic (ROC) curve analysis was conducted. Additionally, univariable and multivariable logistic regression analyses were performed.
RESULTS: In this study, a total of 88 patients were included and followed up for an average of 15.8 months. It was observed that 32.9% (n=29/88) of the patients experienced cage subsidence. The post-surgery disc height was significantly higher in patients who experienced subsidence compared to those who did not. The mean EBQ scores for patients with non-subsidence and subsidence were 2.31±0.6 and 3.48±1.2, respectively, and this difference was statistically significant. The ROC curve analysis showed that the AUC for the EBQ score was 0.811 (95% CI: 0.717-0.905). The most suitable threshold for the EBQ score was determined to be 2.318 (sensitivity: 93.1%, specificity: 55.9%). Additionally, the multivariate logistic regression analysis revealed a significant association between a higher EBQ score and an increased risk of subsidence (odds ratio [OR]=6.204, 95% CI=2.520-15.272, p<.001).
CONCLUSIONS: Our findings indicate that higher preoperative EBQ scores are significantly linked to cage subsidence following single-level OLIF. Preoperative measurement of MRI can serve as a valuable tool in predicting cage subsidence.

UNASSIGNED: There currently exists some controversy about the efficacy of oblique lumbar interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in the treatment of lumbar degenerative diseases.
UNASSIGNED: This study compares the application effects of OLIF and TLIF in lumbar degenerative diseases by reviewing the literature and using meta-analysis.
UNASSIGNED: We included randomized controlled trials and cohort studies comparing TLIF and OLIF in the treatment of lumbar degenerative diseases. We searched for words such as \"intervertebral disc degeneration,\" \"spinal fusion,\" and \"lumbar vertebrae\" in the PubMed, Embase, and Cochrane Library databases. The search date was set from the establishment date of the database to October 2023. Two authors independently conducted document screening, data abstraction, and qualitative assessment. A meta-analysis was performed and adapted to RevMan5.3 software. The odds ratio (OR), weighted mean difference (WMD), and 95% CI were calculated by adopting a fixed-effect model (FEM) or a random-effect model (REM).
UNASSIGNED: A total of 18 cohort studies were included with 1,550 patients, of whom 806 patients underwent TLIF (TLIF group) and 744 patients underwent OLIF (OLIF group). There were no significant differences found in the fusion rate [OR = 1.58 (0.95, 2.64), P = 0.08], complication rate [OR = 1.25 (0.93, 1.68), P = 0.14], and visual analog scale for back pain (VAS-BP) [WMD = 0.00 (-0.13, 0.14), P = 0.96] between the two groups. Compared with the TLIF group, the OLIF group had a lower Oswestry disability index (ODI) [WMD = -0.62 (-1.03, -0.20), P = 0.003], a higher foramen height (FH) [WMD = 2.03 (1.42, 2.46), P < 0.001], a higher disc height (DH) [WMD = 1.69 (1.17, 2.22), P < 0.001], and a shorter length of stay (LOS) [WMD = -1.80 (-2.55, -1.05), P < 0.001].
UNASSIGNED: In the treatment of lumbar degenerative diseases, compared with TLIF, OLIF has more advantages in terms of improving the lumbar function, restoring the FH and DH, and shortening the LOS. Both methods have comparable fusion rates, complication rates, and lumbar pain improvements. Due to the small amount of research and unclear assessment of the risk of bias, high-quality, large-sample randomized controlled studies are required to prove it.

BACKGROUND: Oblique lumbar interbody fusion (OLIF) procedures have the potential to increase the segmental lordosis by inserting lordotic cages, however, the amount of segmental lordosis (SL) changes can vary and is likely influenced by several factors, such as patient characteristics, radiographic parameters, and surgical techniques. The objective of this study was to analyze the impact of related factors on the amount of SL changes in OLIF procedures and to build up predictive model for SL changes.
METHODS: This is a retrospective study involving prospectively enrolled patients. A total of 119 patients with 174 segments undergoing OLIF procedure were included and analyzed. The lordotic cages used in all cases had 6-degree angle. Radiographic parameters including preoperative and postoperative segmental disc angle (SDA, preSDA and postSDA), SDA changes on flexion-extension views (ΔSDA-FE), CageLocation and CageInclination were measured by two observers. Interobserver reliability of measurements were ensured by analysis of interclass correlation coefficient (ICC > 0.75). Pearson correlation coefficient analysis and multivariate linear regression were employed to identify factors related to SDA changes and to build up predictive model for SDA changes.
RESULTS: The average change of segmental disc angle (ΔSDA, postSDA-preSDA) was 3.9° ± 4.8° (95% confidence interval [CI]: 3.1°-4.6°) with preSDA 5.3° ± 5.0°. ΔSDA was 10.8° ± 3.2° with negative preSDA (kyphotic), 5.0° ± 3.7° with preSDA ranging from 0° to 6°, and 1.0° ± 4.1° with preSDA> 6°. Correlation analysis revealed a significant negative correlation between ΔSDA and preSDA (r = - 0.713, P < 0.001), CageLocation (r = - 0.183, P = 0.016) and ΔSDA-FE (r = - 0.153, P = 0.044). In the multivariate linear regression, preSDA and CageLocation were included in the predictive model, resulting in minimal adjusted R2 change (0.017) by including CageLocation. Therefore, the recommended predictive model was ΔSDA = 7.9-0.8 × preSDA with acceptable fit. (adjusted R2 = 0.508, n = 174, P < 0.001).
CONCLUSIONS: The restoration of segmental lordosis through OLIF largely depends on the preoperative segmental lordosis. The predictive model, which utilized preoperative segmental lordosis, facilitates preoperative planning for corrective surgery using the OLIF procedure.

This was a single-centre retrospective study. Minimally invasive techniques for transforaminal lumbar interbody fusion (MIS-TLIF), oblique lumbar interbody fusion (OLIF), and percutaneous endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) have been extensively used for lumbar degenerative diseases. The present study analyses the short-term and mid-term clinical effects of the above three minimally invasive techniques on L4/L5 degenerative spondylolisthesis. In this retrospective study, 98 patients with L4/L5 degenerative spondylolisthesis received MIS-TLIF, 107 received OLIF, and 114 received Endo-TLIF. All patients were followed up for at least one year. We compared patient data, including age, sex, body mass index (BMI), Oswestry disability index (ODI), visual analogue scale of low back pain (VAS-B), visual analogue scale of leg pain (VAS-L), surgical time, blood loss, drainage volume, hospital stay, complications, and neurological status. Moreover, we performed imaging evaluations, including lumbar lordosis angle (LLA), disc height (DH) and intervertebral fusion status. No significant differences were noted in age, sex, BMI, preoperative ODI, preoperative VAS-B, preoperative VAS-L, preoperative LLA, or preoperative DH. Patients who underwent OLIF had significantly decreased blood loss, a lower drainage volume, and a shorter hospital stay than those who underwent MIS-TLIF or Endo-TLIF (P < 0.05). The VAS-B in the OLIF group significantly decreased compared with in the MIS-TLIF and Endo-TLIF groups at 6 and 12 months postoperatively (P < 0.05). The VAS-L in the Endo-TLIF group significantly decreased compared with that in the MIS-TLIF and OLIF groups at 6 months postoperatively (P < 0.05). The ODI in the OLIF group was significantly better than that in the MIS-TLIF and Endo-TLIF groups at 6 months postoperatively (P < 0.05). No statistically significant differences in the incidence of complications and healthcare cost were found among the three groups. Follow-up LLA and DH changes were significantly lower in the OLIF group than in the other groups (P < 0.05). The intervertebral fusion rate was significantly higher in the OLIF group than in the other groups at 6 and 12 months postoperatively (P < 0.05). In conclusion, while MIS-TLIF, OLIF, and Endo-TLIF techniques can effectively treat patients with L4/5 degenerative spondylolisthesis, OLIF has more benefits, including less operative blood loss, a shorter hospital stay, a smaller drainage volume, efficacy for back pain, effective maintenance of lumbar lordosis angle and disc height, and a higher fusion rate. OLIF should be the preferred surgical treatment for patients with L4/5 degenerative spondylolisthesis.

BACKGROUND: Oblique lumbar interbody fusion (OLIF) is an internationally popular minimally invasive technology for the treatment of various lumbar diseases. Since its introduction to China in 2014, OLIF technology has clearly shown its superiority in reconstructing intervertebral stability, restoring intervertebral space height, achieving indirect decompression, and restoring normal lumbar sequence. However, some patients still suffer from persistent symptoms after OLIF, including low back pain and soreness, which indirectly affect the overall surgical efficacy and patient satisfaction. Therefore, some clinicians recommend that patients routinely use spinal orthoses after OLIF to reduce the stress on the lower back muscles and ligaments, thereby relieving or avoiding postoperative residual symptoms or new symptoms. Accordingly, spinal orthosis use after OLIF has emerged as an essential option. However, the role of spinal orthoses in OLIF and their specific impact on postoperative patient clinical outcomes have remained unclear, and there is a lack of strong clinical evidence to indirectly or directly support the role of spinal orthoses in OLIF and demonstrate their impact on patient clinical outcomes. This study aims to investigate the role of spinal orthoses in OLIF by grouping patients based on the use or nonuse of spinal orthosis after OLIF, thus providing a better basis for the majority of patients and physicians.
METHODS: We plan to conduct a 1-year randomized controlled trial involving 60 subjects. The subjects will be randomized into two groups: group A (those wearing spinal orthoses after surgery) and group B (those not wearing spinal orthoses after surgery). The clinical outcomes of these patients will be evaluated using the Oswestry disability index, visual analog scale, and Brantigan, Steffee, Fraser 1 day before surgery and 2 weeks and 1, 6, and 12 months after surgery.
CONCLUSIONS: This randomized controlled trial aims to provide a reference for further comprehensive trial design. The findings of this study will provide a better and more scientific basis for the choice of postoperative rehabilitation and treatment for patients undergoing such a procedure.
BACKGROUND: This study has been registered in the Chinese Clinical Trial Registry (Registration No.: ChiCTR2200059000). Registration date: April 22, 2022. Registration website: http://www.chictr.org.cn/showproj.aspx?proj=166310.

BACKGROUND: Oblique lumbar interbody fusion (OLIF) has been a popular technique for treating lumbar degenerative diseases. Previous studies have shown its efficiency in lumbar spinal stenosis; yet, only a few studies have investigated its application to severe lumbar spinal stenosis. Herein, we investigated the clinical and radiographic outcome of OLIF with percutaneous pedicle screws in the treatment of severe lumbar spinal stenosis.
METHODS: A total of 15 patients who underwent OLIF with percutaneous pedicle screws were retrospectively analysed. All patients were diagnosed with severe lumbar stenosis (Schizas grade C or D) through preoperative magnetic resonance image (MRI) and received OLIF combined with percutaneous pedicle screw surgery. Clinical outcomes, including visual analogue scale (VAS)-back and VAS-leg scores, and Oswestry Disability Index (ODI), as well as mean disc height (DH), mean foraminal height (FH), segmental lumbar lordosis (SLL) and cross-sectional area (CSA) of the spinal canal, were analysed before and after surgery and at the last follow-up. Intraoperative data, complications and fusion rate were also investigated.
RESULTS: OLIF combined with percutaneous pedicle screws was performed on 18 segments in 15 patients. Mean follow-up was 23.1 ± 4.6 months (range 15-29 months). VAS-back, VAS-leg, and ODI scores were significantly improved at the last follow-up. DH increased from 8.86 ± 3.06 mm before surgery to 13.31 ± 2.14 mm after; at the last follow-up, DH was 11.69 ± 1.87 mm. FH increased from 17.85 ± 2.26 mm before surgery to 22.09 ± 1.36 mm after; at the last follow-up, FH was 20.41 ± 0.99 mm. CSA of the spinal canal increased from 30.83 ± 21.15 mm2 before surgery to 74.99 ± 33.65 mm2 after the operation and 81.22 ± 35.53 mm2 at the last follow-up. The segmental LL before surgery, after surgery and at last follow-up was 20.27 ± 6.25 degrees, 20.83 ± 6.52 degrees and 19.75 ± 5.87 degrees, respectively. All patients have gained fusion at the last follow-up.
CONCLUSIONS: OLIF with percutaneous pedicle screws could achieve satisfactory clinical and radiographic effects through indirect compression by increasing DH, FH and CSA of the spinal canal in severe lumbar stenosis patients.

Objective: Using finite element analysis to identify the optimal internal fixation method for oblique lateral lumbar interbody fusion (OLIF), providing guidance for clinical practice. Methods: A finite element model of the L4 - L5 segment was created. Five types of internal fixations were simulated in the generated L4-L5 finite element (FE) model. Then, six loading scenarios, i.e., flexion, extension, left-leaning, right-leaning, rotate left, and rotate right, were simulated in the FE models with different types of fixations. The biomechanical stability of the spinal segment after different fixations was investigated. Results: Regarding the range of motion (ROM) of the fused segment, OLIF + Bilateral Pedicle Screws (BPS) has a maximum ROM of 1.82° during backward bending and the smallest ROM in all directions of motion compared with other models. In terms of the von Mises stress distribution on the cage, the average stress on every motion direction of OLIF + BPS is about 17.08MPa, and of OLIF + Unilateral Vertebral Screw - Pedicle Screw (UVS-PS) is about 19.29 MPa. As for the von Mises stress distribution on the internal fixation, OLIF + BPS has the maximum internal fixator stress in left rotation (31.85 MPa) and OLIF + Unilateral Pedicle Screw (UPS) has the maximum internal fixator stress in posterior extension (76.59 MPa). The data of these two models were smaller than those of other models. Conclusion: OLIF + BPS provides the greatest biomechanical stability, OLIF + UPS has adequate biomechanical stability, OLIF + UVS-PS is inferior to OLIF + UPS synthetically, and OLIF + Double row vertical screw (DRVS) and Individual OLIF (IO) do not present significant obvious advantages.

Oblique lateral interbody fusion (OLIF) surgery is a minimally invasive spinal surgery technique that has become increasingly popular in recent years. The primary objective of the current study was to design a minimally invasive expandable fusion device that can reduce iatrogenic nerve damage and minimize endplate damage during OLIF surgery, while restoring intervertebral height and alignment. The second objective was to use finite element analysis to evaluate the biomechanical stability of the newly designed expandable fusion device after implantation into the intervertebral space.
A new bidirectional expandable cage was designed in this study. A finite element model (FEM) of L3-L5 lumbar segment was modified to simulate decompression and fusion. The modified FEMs were constructed in the following cases: intact model, bidirectional expandable cage (alone, with unilateral pedicle screws [UPSs], and with bilateral pedicle screws [BPSs]) model, conventional OLIF cage (alone, with UPSs, and with BPSs) model. To simulate physiological loadings, the models were subjected to a follower compressive pre-load of 400 N, in addition to 8.0 Nm of flexion, extension, lateral bending, and axial rotation moments.
All modified FEMs exhibited a significant reduction in motion at L3-L5 compared to the intact model. Among the fusion models, the bidirectional expandable cage (BEC) with BPS model displayed the highest stiffness and demonstrated a reduced range of motion (48.5%-75.7%). Additionally, the peak stress on the endplate in the conventional OLIF cage (Conv-OLIF) model was generally lower than that in the BEC models. The cage in the BEC ALONE model exhibited the highest stress (93.87-176.3 MPa) on the endplate in most motion modes, while the cage in the Conv-OLIF+BPS model had the lowest stress (16.67-30.58 MPa) on the endplate in most motion modes. The maximum stress on the fixation in the BEC fusion models was generally lower than that in the Conv-OLIF fusion group under the same loading conditions. The OLIF ALONE model had the lowest stress on the adjacent disc, while the stress level in the BEC ALONE model was very close to it.
The BEC implanted models had higher stiffness, and more proper stress distribution on the posterior fixation was comparable to that of the Conv-OLIF models. However, the endplate stress peaks and cage stress peaks of the BEC models were slightly higher than those of the Conv-OLIF models, though still within a clinically acceptable range. Taking into account both biomechanical and clinical perspectives, BEC-assisted unilateral pedicle screw fixation meet clinical demand and may serve as a viable alternative to Conv-OLIF fusion.