OBJECTIVE: Oblique lumbar interbody fusion (OLIF) has become a popular technique for treating adult degenerative scoliosis (ADS), but traditional OLIF technology often requires repositioning for one-stage or staged posterior fixation. The objective of this pilot study was to describe the surgical technique of simultaneous single-position OLIF and percutaneous pedicle screw fixation (OLIF 360) under O-Arm navigation for modified MISDEF type II ADS.
METHODS: Between June 2022 and December 2023, six patients classified as having modified MISDEF type II ADS underwent OLIF 360 assisted by O-Arm navigation at our institution. Intraoperative blood loss, duration of operation, and complications related to the OLIF 360 procedure were recorded. The preoperative and postoperative spinal pelvic parameters were measured using X-rays. The accuracy of pedicel screws was recorded in accordance with the modified Gertzbein-Robbins classification on CT. Postoperative MRI was performed to evaluate the indirect decompressive effect. The Japanese Orthopedic Association score for low back pain was used to evaluate surgical outcomes.
RESULTS: Navigated OLIF 360 were performed in six ADS patients with 44 percutaneous pedicel screws and 16 cages placement, including four women and two men. The mean operation time was 160.83 ± 33.23 min, and the mean blood loss was 111.67 ± 39.71 mL. Postoperative spinal pelvic parameters and spinal stenosis degree improved significantly on X-ray and MRI. All screws were clinically acceptable according to the Gertzbein-Robbins classification, with 92.7% grade A and 7.3% grade B. No serious intraoperative and postoperative adverse events were recorded in all patients. The JOA scores for low back pain of all patients were significantly improved at postoperative 1 month and the final follow-up.
CONCLUSIONS: We report on a case series and describe navigated OLIF 360 in treating modified MISDEF type II ADS patients. Navigation-assisted OLIF 360 has shown encouraging surgical outcomes with good spinal imbalance correction and indirect decompression.

OBJECTIVE: To evaluate the outcomes of Oblique lumbar interbody fusion (OLIF)combined with anterolateral screw fixation (AF) and Stress Endplate Augmentation(SEA) versus OLIF-AF in the treatment of degenerative lumbar spondylolisthesis (DLS)with osteoporosis (OP).
METHODS: 30 patients underwent OLIF-AF-SEA (SEA group) were matched with 30 patients received OLIF-AF (control group), in terms of sex, age, body mass index (BMI) and bone mineral density (BMD). Clinical outcomes including visual analog scale (VAS) score of the lower back pain (VAS-LBP), leg pain (VAS-LP), and Oswestry Disability Index (ODI) were evaluated at different postoperative intervals and comparedwith their preoperative counterparts. Radiographic outcomes such as disk height (DH), slip distance (SD), lumbar lordosis (LL), segmental lordosis (SL), cage subsidence (CS) rate and fusion rate were evaluated at different postoperative intervals and compared with their preoperative counterparts.
RESULTS: SEA group presented to be better at 3-month and 12-month follow-up, the VAS-LBP, VAS-LP and ODI scores of the SEA group were significantly lower than the control group (3-month SEA vs control: 2.30±0.70 vs 3.30±0.75, 2.03±0.72 vs 2.90±0.76,15.60±2.36 vs 23.23±3.07, respectively, all p<0.05. VAS-LBP and ODI 12-month SEA vs control: 1.27±0.74 vs 1.93±0.58, 12.20±1.88 vs 14.43±1.89,respectively, all p<0.05). At 24-month follow-up, both groups showed no difference in fusion rate (83.33% vs 90.00%, p=0.45), while SEA group showed a lower CS rate (13.33% vs 53.33%, p<0.05).
CONCLUSIONS: OLIF-AF-SEA was safe with no adverse effects and resulted in lower CS rate and better sagittal balance. OLIF-AF-SEA is a promising surgical method for treating patients with DLS-OP.

OBJECTIVE: The study investigates how cage positions in oblique lumbar interbody fusion (OLIF) combined with posterior percutaneous pedicle screw internal fixation (PPSF) affect lumbar canal and foraminal decompression and postoperative outcomes, providing guidance for optimal placement and efficacy assessment.
METHODS: This investigation assesses radiologic outcomes and follow-up data in relation to cage position variability among 80 patients who underwent L4/5 single-segment OLIF + PPSF from 2018 to 2022.
RESULTS: In the study involving 80 participants, the combination of OLIF and PPSF significantly improved lower back and leg symptoms in patients, leading to positive clinical outcomes during follow-up. The intervertebral disk height increased from an average of 8.10 ± 2.79 mm before surgery to 11.75 ± 2.14 mm after surgery (P < 0.001). Additionally, this surgical technique notably increased the FH (P < 0.001) and expanded the DCSA from 68.81 ± 53.89 mmˆ2 before surgery to 102.91 ± 60.46 mmˆ2 after surgery (P < 0.001). Linear results suggest that changes in the position of the cage do not affect spinal imaging parameters. There is no significant difference in the correction of spinal parameters or prognosis whether the cage is back, middle, ahead.
CONCLUSIONS: In the OLIF + PPSF procedure, strict requirements for cage position are not necessary to achieve predetermined spinal biomechanical parameters. The practice of repeated fluoroscopy to adjust cage position postimplantation does not provide added clinical benefits to the patient.

Objective To demonstrate the feasibility of oblique lumbar interbody fusion (OLIF) combined with 4-screw fixation for treating two-level lumbar degenerative diseases.Methods An intact finite element model of L3-S1 (M0) was constructed and validated.Then,we constructed the M1 model by simulating OLIF surgery at L3/4 and L4/5 segments on the M0 model.By attachment of posterior 4-screw or 6-screw fixation to the M1 model,three 4-screw fixation models (M2-M4) and one 6-screw fixation model (M5) were established.The segmental and overall range of motion (ROM) and the peak von Mises stresses of superior endplate,cage,and posterior screw-rod were investigated under each implanted condition.Results Under the motion modes of forward flexion,backward extension,bilateral (left and right) flexion,and left and right rotation,the L3/4 ROM of M2 model and L4/5 ROM of M3 model increased,while the L3/4 and L4/5 ROM of M4 and M5 models significantly decreased compared with those of M1 model.Under all motion modes,the L4 superior endplate in M2 model and the L5 superior endplate in M3 model showed the maximum peak von Mises stress,and the peak von Mises stresses of L4 and L5 superior endplates in M4 and M5 models were close.The L3/4 cage in M2 model and the L4/5 cage in M3 model showcased the largest peak von Mises stress,and the peak von Mises stresses of cages in M4 and M5 models were close.The peak stresses of internal fixation in M2-M5 models were close.Conclusion Four-screw fixation can replace 6-screw fixation in the OLIF surgery for treating two-level degenerative lumbar diseases.
目的 探讨斜外侧腰椎椎间融合术(OLIF)结合4钉固定法治疗两节段腰椎退变性疾病的可行性。方法 构建并验证L3~S1节段腰椎有限元模型(M0),于M0模型上模拟L3/4及L4/5两节段OLIF手术构建M1模型。在M1模型上附加后路4钉或6钉固定,建立3个4钉固定模型(M2~M4)和1个6钉固定模型(M5)。分析不同内固定条件下融合节段和整体活动度以及上终板、融合器、后路钉棒所受应力峰值的变化。结果 在前屈、后伸、左右侧屈及左右旋转6种运动下,与M1模型比较,M2模型L3/4和M3模型L4/5节段活动度增加,M4和M5模型L3/4、L4/5节段活动度明显下降。在不同运动下,M2模型L4上终板von Mises应力峰值最大,M3模型L5上终板von Mises应力峰值最大,M4和M5模型L4及L5上终板von Mises应力峰值较为接近;M2模型L3/4融合器von Mises应力峰值最大,M3模型L4/5融合器von Mises应力峰值最大,M4和M5模型各融合器von Mises应力峰值较为接近;M2~M5模型内固定最大应力峰值较为接近。结论 在两节段OLIF手术中,4钉固定可以有效替代6钉固定用于腰椎退变性疾病的治疗。.

Despite the fact that lower back pain caused by degenerative lumbar spine pathologies seriously affects the quality of life, however, there is a paucity of research on the biomechanical properties of different auxiliary fixation systems for its primary treatment (oblique lumbar interbody fusion) under vibratory environments. In order to study the effects of different fixation systems of OLIF surgery on the vibration characteristics of the human lumbar spine under whole-body vibration (WBV), a finite element (FE) model of OLIF surgery with five different fixation systems was established by modifying a previously established model of the normal lumbar spine (L1-S1). In this study, a compressive follower load of 500 N and a sinusoidal axial vertical load of ±40 N at the frequency of 5 Hz with a duration of 0.6 s was applied. The results showed that the bilateral pedicle screw fixation model had the highest resistance to cage subsidence and maintenance of disc height under WBV. In contrast, the lateral plate fixation model exerted very high stresses on important tissues, which would be detrimental to the patient\'s late recovery and reduction of complications. Therefore, this study suggests that drivers and related practitioners who are often in vibrating environments should have bilateral pedicle screws for OLIF surgery, and side plates are not recommended to be used as a separate immobilization system. Additionally, the lateral plate is not recommended to be used as a separate fixation system.

暂无摘要。

METHODS: A retrospective study.
OBJECTIVE: This study aimed to check how accurately cages were inserted and how they affected the radiological results in oblique lumbar interbody fusion (OLIF) at L2-L5.
METHODS: A total of 137 patients diagnosed with lumbar degenerative disease, 184 intervertebral discs were included. We used a new cage deviation classification system on magnetic resonance imaging (MRI) to determine cage insertion accuracy. Cage deviation angles (CDA) were classified into four groups based on the angle formed by the long axis of the cage and the horizontal axis of the vertebral body. Other radiological parameters on plain radiographs and MRI were compared based on this classification.
RESULTS: Among 183 cages, 19 were in zone Ⅰ-Ⅱ (10.32%), 163 were in zone II-III (88.59%), and two were in zone III-IV (1.09%). The median cage deviation was 4.97°. No significant differences (H = 2.479, P = .290 > .05) of CDA were found among different segments. Posterior cage deviation accounted 94.57%. The minimal, mild, moderate, and severe cage deviation was 89 (48.4%), 51 (27.7%), 30 (16.3%), and 14 (7.6%) respectively. No differences in radiological parameter changes were noted among different cage obliquity categories.
CONCLUSIONS: Approximately 98.91% of cages were placed in zones I-II and II-III. Most cages deviated posteriorly with CDA ranging minimal to moderate. Minimal to moderate cage deviation did not impact radiological outcomes significantly in OLIF at L2-L5. However, avoiding severe cage deviation is crucial to prevent contralateral traversing nerve root injuries.

BACKGROUND: Oblique lateral lumbar fusion (OLIF) is widely used in spinal degeneration, deformity and other diseases. The purpose of this study was to investigate the biomechanical differences between two different shapes of OLIF cages on whether to add posterior internal fixation system, using finite element analysis.
METHODS: A complete three-dimensional finite element model is established and verified for L3-L5. Surgical simulation was performed on the verified model, and the L4-L5 was the surgical segment. A total of the stand-alone group (Model A1, Model B1) and the BPSF group (Model A2, Model B2) were constructed. The four OLIF surgical models were: A1. Stand-alone OLIF with a kidney-shaped Cage; B1. Stand-alone OLIF with a straight cage; A2. OLIF with a kidney-shaped cage + BPSF; B2. Stand-alone OLIF with a straight cage + BPSF, respectively. The differences in the range of motion of the surgical segment (ROM), equivalent stress peak of the cage (ESPC), the maximum equivalent stress of the endplate (MESE) and the maximum stress of the internal fixation (MSIF) were compared between different models.
RESULTS: All OLIF surgical models showed that ROM declines between 74.87 and 96.77% at L4-L5 operative levels. The decreasing order of ROM was Model A2 > Model B2 > Model A1 > Model A2. In addition, the ESPC and MESE of Model A2 are smaller than those of other OLIF models. Except for the left-bending position, the MSIF of Model B2 increased by 1.51-16.69% compared with Model A2 in each position. The maximum value of MESE was 124.4 Mpa for Model B1 in the backward extension position, and the minimum value was 7.91 Mpa for Model A2 in the right rotation. Stand-alone group showed significantly higher ROMs and ESPCs than the BPSF group, with maximum values of 66.66% and 70.59%. For MESE, the BPSF group model can be reduced by 89.88% compared to the stand-alone group model.
CONCLUSIONS: Compared with the traditional straight OLIF cage, the kidney-shaped OLIF cage can further improve the stability of the surgical segment, reduce ESPC, MESE and MSIF, and help to reduce the risk of cage subsidence.

BACKGROUND: While there have been previous studies on the surgical efficacy of patients with redundant nerve roots (RNRs), a persistent issue is that some patients continue to experience redundancy even after surgery. Furthermore, the clinical significance of RNRs remains unclear. Notably, there is a lack of research regarding RNRs within the context of oblique lumbar interbody fusion (OLIF) combined with percutaneous internal fixation. Therefore, the primary objective of this study is to investigate the correlation between RNRs and clinical outcomes following OLIF combined with percutaneous internal fixation.
METHODS: Eighty-seven patients diagnosed with lumbar spinal stenosis (LSS) who underwent single-segment OLIF combined with percutaneous internal fixation were categorized into three groups. Group 1 comprised patients with positive RNRs both before and after the operation. Group 2 included patients with positive RNRs preoperatively but negative RNRs postoperatively. Group 3 consisted of patients with consistently negative RNRs before and after the operation. Comprehensive patient data were collected, including operation time, intraoperative blood loss, and any recorded complications. Radiographic parameters, both pre- and post-operative, were assessed, encompassing the number of stenosis segments, disc height (DH), lumbar lordotic angle, dural sac cross-sectional area, and the placement of the fusion cage. Furthermore, the Visual Analogue Scale was applied to gauge back and leg pain, while the Oswestry Disability Index was employed to appraise daily living activities. A comparative analysis was carried out among the three patient groups.
RESULTS: In this study, all 87 LSS patients successfully underwent surgery. Among them, 35 patients (40.2%) showed preoperative MRI assessment indicating positive RNRs. In the postoperative MRI assessment, 14 of these patients maintained positive RNRs status, and they were grouped into Group 1. The remaining 21 patients saw a transition to negative RNRs status and were included in Group 2. Among the 52 patients who had preoperative MRI assessments showing negative RNRs, their postoperative RNRs status remained negative, forming Group 3. All patients received follow-up, which ranged from 8 to 18 months, and no complications occurred during this period. In this study, the postoperative efficacy and parameters such as DH and Dural Sac CSA significantly improved compared to preoperative values for all 87 patients. Patients with preoperative RNRs had more stenosis segments, smaller dural sac CSA, and more severe symptoms. In all three groups, postoperative efficacy scores significantly improved compared to preoperative scores. Group 2 patients had their fusion cages placed more in the middle, while Group 1 patients had their fusion cages more anteriorly located. Group 2 patients exhibited greater recovery in dural sac CSA postoperatively compared to Group 1 patients. Additionally, Group 2 patients had better ODI efficacy scores compared to Group 1 patients.
CONCLUSIONS: Irrespective of the presence or absence of RNRs, patients experienced improvement after undergoing OLIF combined with percutaneous internal fixation. Preoperative RNRs appear to be linked to multi-segmental lumbar spinal stenosis, a reduction in dural sac CSA, and symptom severity. Patients with negative postoperative RNRs demonstrated better treatment efficacy. Furthermore, the placement of the fusion cage appears to have a significant impact on postoperative efficacy and RNRs outcomes.

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.