Lateral Interbody Fusion Research Articles

Incidental Ureteral Complication in Single-Center Consecutive Oblique Lateral Interbody Fusion Cases.

Oblique lateral interbody fusion (OLIF) has recently gained widespread use as a minimally invasive surgical procedure for degenerative lumbar disease. OLIF has several advantages but can also lead to several possible complications. For example, although less common, access through the retroperitoneal cavity can cause ureteral injury. Here, we report two cases of ureteral complications that occurred during consecutive OLIF procedures. One involved a 77-year-old female patient who had a double-J catheter inserted due to ureteral injury during surgery, and the other involved a 69-year-old male patient suspected of having a ureteral stricture due to retractor compression. To prevent ureteral complications in OLIF, it is necessary to accurately identify the anatomy of the ureter through preoperative imaging and to pay special attention during surgery.

Extreme Lateral Interbody Fusion (XLIF) with Lateral Modular Plate Fixation: Preliminary Report on Clinical and Radiological Outcomes.

The lateral transpsoas approach (extreme lateral interbody fusion, or XLIF) allows surgeons to use various lordotic cage sizes to help restore intervertebral disk height, correct sagittal alignment, and improve fusion rates. The use of standalone devices has consistently raised doubts due to the high risk of complications and inadequate functional recovery that a circumferential arthrodesis can support. The recent introduction of a novel XLIF cage with adapted lateral plate fixation (XLPF) may further enhance the structural rigidity, consolidating the cage and plate into a singular modular entity. Nine patients from our surgical centers underwent a procedure of 1-level XLIF with XLPF in selected cases. We observed that XLPF does not extend the intraoperative footprint and provides immediate rigidity to the anterior column without any additional risk of complications and with minimal increased time compared to the traditional cage implant procedure. Although it has been shown that the use of interbody fusion cages with supplemental posterior fixation improves stabilization in all directions, the technique of standalone lateral cages may also have a place in spine surgery in that the stability may be sufficient in selected cases, such as junctional syndrome and in some forms of degenerative scoliosis.

Short-Term Comparison Between Unilateral Versus Bilateral Percutaneous Pedicle Screw Fixation in Short-Level Lateral Lumbar Interbody Fusion-A Prospective Randomized Study.

Prospective randomized controlled trial. No prospective studies have directly compared clinical and radiographic outcomes of unilateral vs bilateral instrumented lateral lumbar interbody fusion (LLIF) for lumbar degenerative disease (LDD). We compared the short-term radiographic, clinical outcomes, and some complications of the unilateral percutaneous pedicle screw (PPS) (UPS) vs bilateral PPS (BPS) fixation in short-level spinal fusion with LLIF for LDD. This was a prospective randomized controlled study of 33 patients who underwent UPS or BPS fixation after LLIF for LDD; 18 patients were assigned to the UPS group and 15 patients to the BPS group. Clinical outcomes, complication rates, and fusion rates were assessed. The two groups were similar in age, sex, preoperative diagnosis, and level of surgery. Blood loss, length of hospital stay, and numeric rating scale score one year after surgery did not differ between groups. The operative time was longer in the BPS than UPS group (120.2 vs 88.8min, respectively; P = .029). Both groups showed improvement in disc height and dural sac in the immediate postoperative computed tomography and magnetic resonance imaging, which did not differ significantly between groups. The subsidence grade and fusion rate did not differ, but cage subsidence was more severe in the UPS than BPS group. Unilateral and bilateral PPS fixation after LLIF yielded similar short-term clinical and radiological outcomes. However, severe cage subsidence was more common in the UPS group, which suggests that BPS fixation after LLIF may be a better choice over the long term.

Single-Position Oblique Lumbar Interbody Fusion and Percutaneous Pedicle Screw Fixation under O-Arm Navigation: A Retrospective Comparative Study

The insertion of pedicle screws in the lateral position without a position change has been reported. We completed a retrospective comparison of the radiologic and clinical outcomes of 36 patients who underwent either single-position oblique lateral lumbar interbody fusion (SP-OLIF) using the O-arm (36 cases) or conventional OLIF (C-OLIF) using the C-arm (20 cases) for L2-5 single-level lumbar degenerative diseases. Radiological parameters were analyzed, including screw accuracy (Gertzbein-Robbins classification system; GRS), segmental instability, and fusion status. Screw misplacement was defined as a discrepancy of ≥2 mm. Clinical outcomes, including visual analog scale, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36), and postoperative complications, were assessed. The spinal fusion rate was not different between the SP-OLIF and C-OLIF groups one year after surgery (p = 0.536). The ODI score was lower (p = 0.015) in the SP-OLIF than the C-OLIF group. Physical (p = 0.000) and mental component summaries (p = 0.000) of the SF-36 were significantly higher in the SP-OLIF group. Overall complication rates, including revision, surgical site infection, ipsilateral weakness, and radicular pain/numbness, were not significantly different. SP-OLIF using the O-arm procedure is feasible, with acceptable accuracy, fusion rate, and complication rate. This may be an alternative to conventional two-stage operations.

Biomechanical Comparison of Unilateral and Bilateral Pedicle Screw Fixation after Multilevel Lumbar Lateral Interbody Fusion.

Human Cadaveric Biomechanical Study. Lumbar Lateral Interbody Fusion (LLIF) utilizing a wide cage has been reported as having favorable biomechanical characteristics. We examine the biomechanical stability of unilateral pedicle screw and rod fixation after multilevel LLIF utilizing 26mm wide cages compared to bilateral fixation. Eight human cadaveric specimens of L1-L5 were included. Specimens were attached to a universal testing machine (MTS 30/G). Three-dimensional specimen range of motion (ROM) was recorded using an optical motion-tracking device. Specimens were tested in 3 conditions: 1) intact, 2) L1-L5 LLIF (4 levels) with unilateral rod, 3) L1-L5 LLIF with bilateral rods. From the intact condition, LLIF with unilateral rod decreased flexion-extension by 77%, lateral bending by 53%, and axial rotation by 26%. In LLIF with bilateral rods, flexion-extension decreased by 83%, lateral bending by 64%, and axial rotation by 34%. Comparing unilateral and bilateral fixation, LLIF with bilateral rods reduced ROM by a further 23% in flexion-extension, 25% in lateral bending, and 11% in axial rotation. The difference was statistically significant in flexion-extension and lateral bending (P < .005). Considerable decreases in ROM were observed after multilevel (4-level) LLIF utilizing 26mm cages supplemented with both unilateral and bilateral pedicle screws and rods. The addition of bilateral fixation provides a 10-25% additional decrease in ROM. These results can inform surgeons of the incremental biomechanical benefit when considering unilateral or bilateral posterior fixation after multilevel LLIF.

Clinical and radiographic outcomes of stand-alone oblique lateral interbody fusion in the treatment of adult degenerative scoliosis: a retrospective observational study

BackgroundOpen fusion and posterior instrumentation has traditionally been the treatment for adult degenerative scoliosis (ADS). However, minimally invasive treatment such as oblique lateral interbody fusion (OLIF) technique was developed as a new therapeutic method for the treatment of ADS. In addition, it is associated with decreased blood loss and shorter operative time without posterior instrument. The purpose of this study was to evaluate the efficiency of stand-alone OLIF for the treatment of ADS in terms of clinical and radiological results.MethodsA total of 30 patients diagnosed with ADS who underwent stand-alone OLIF in our hospital from July 2017 to September 2018 were enrolled in the study. Scores from the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) obtained preoperatively and at the final follow-up were compared. Radiography and computed tomography were performed preoperatively and at the final follow-up. The coronal cobb angle, lumbar lordosis, disc height, sacral slope, pelvic incidence and Pelvic tilt were recorded at each time point.ResultsThe study cohort comprised 30 patients with a mean age of 64.5 ± 10.8 years and mean follow-up of 19.3 ± 4.2 months. The mean operative time was 96.8 ± 29.4 minutes and the mean estimated blood loss volume was 48.7 ± 9.4 ml. The mean coronal Cobb angle was corrected from 15.0° ± 3.7° preoperatively to 7.2° ± 3.1° postoperatively and 7.2° ± 3.3° at final follow-up (P < 0.0001). Lumbar lordosis significantly improved from 32.2° ± 11.3° preoperatively to 40.3° ± 11.8° postoperatively and 40.7° ± 11.0° at final follow-up (P < 0.01). The respective mean sacral slope and pelvic tilt improved from 26.1° ± 8.1° and 25.1° ± 6.9° preoperatively to 34.3° ± 7.4° and 19.2° ± 5.7° at final follow-up (P < 0.001). The mean disc height (defined as the mean of the anterior and posterior intervertebral disc heights) increased from 0.7 ± 0.3 cm preoperatively to 1.1 ± 0.2 cm at final follow-up (P < 0.0001). The interbody fusion rate on CT was 93.3%. The mean VAS pain score improved from 5.3 ± 0.6 before surgery to 2.3 ± 0.6 at final follow-up (P < 0.001). The mean ODI improved from 29.9% ± 6.8% preoperatively to 12.8% ± 2.4% at final follow-up (P < 0.001).ConclusionsStand-alone OLIF is an effective and safe option for treating ADS in carefully selected patients.Trial registrationThe study was registered in the Chinese Clinical Trial Registry (ChiCTR2100052419).

Oblique lateral interbody fusion in heterogenous lumbar diseases: Anterolateral screw fixation vs. posterior percutaneous pedicle screw fixation - A single center experience.

Oblique lateral interbody fusion (OLIF) is a type of minimally invasive lateral lumbar interbody fusion technique used for treating lumbar degenerative diseases. This study aimed to analyze the clinical and radiographic efficacy of OLIF with anterolateral screw fixation alone and OLIF requiring fixation with conventional posterior percutaneous pedicle screws for lumbar diseases. Medical records of consecutive patients admitted to Cheng-Hsin Hospital who received OLIF between January 2019 and December 2020 were retrospectively reviewed. Patients were divided into two groups by screw fixation: patients who received anterolateral screw fixation alone were defined as one-stage OLIF (n = 9) and patients who received fixation with conventional posterior percutaneous pedicle screw were defined as two-stage OLIF (n = 16). Patient clinical characteristics, medical history, intraoperative blood loss, length of hospital stay, peri-operative, and post-operative complications were evaluated in all patients. During the study period, a total of 25 patients were successfully treated with OLIF (n = 9 one-stage; n = 16 two-stage). Two-stage OLIF was associated with longer operation times, longer hospital stays, shorter bed-rest time, and a greater likelihood of having a blood transfusion compared with the one-stage OLIF group. A higher proportion of grade I subsidence was observed at 6 months and 1 year after surgery in the two-stage group compared with the one-stage group. Post-operative complications included ileus, dystonia, and dystonia were higher in the two-stage OLIF group. Improvements in radiographic parameters were demonstrated after OLIF, and the improvements were comparable between one-stage and two-stage OLIF. One-stage OLIF is a feasible and efficacious treatment method for single- and multiple-level degenerative lumbar diseases. Additional clinical follow-up is necessary to confirm long-term outcomes.

Impact of preoperative symptom duration in patients undergoing lateral lumbar interbody fusion.

Few studies have examined the influence of preoperative symptom duration on clinical outcomes in patients undergoing lateral lumbar interbody fusion (LLIF) for degenerative conditions. Patients undergoing LLIF presenting with radiculopathy and/or neurogenic claudication were separated into two groups: preoperative symptom duration < 1-year (shorter duration) versus duration ≥ 1-year (longer duration). Patients undergoing surgery for trauma/malignancy/infection were excluded. Patient-reported outcome measures (PROMs) of Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), 12-Item Short Form Physical/Mental Component Score (SF-12 PCS/MCS), Patient Health Questionnaire-9 (PHQ-9), visual analog scale (VAS) back/leg, and Oswestry Disability Index (ODI) were collected at preoperative and postoperative time points. Eighty-two total patients, with 34 shorter-duration patients, were identified after propensity score matching for demographics. Longer-duration patients had higher estimated blood loss. All patients reported significant improvement in physical function, mental function, pain, and disability in at least one postoperative time point, except for SF-12 MCS in the shorter duration cohort. The longer duration cohort had higher MCID achievement in 12-week VAS back. Patients undergoing LLIF demonstrated significant postoperative improvement in physical function, mental function, pain, and disability outcomes independent of preoperative symptom duration. Both cohorts, when compared by preoperative symptom duration, demonstrated similar postoperative PROM scores. Patients with longer preoperative symptom duration had higher 12-week leg pain MCID achievement. These findings suggest that delayed time to surgery may not lead to inferior clinical outcomes in patients undergoing LLIF for degenerative conditions.

Comparison of oblique lateral lumbar interbody fusion and transforaminal lumbar interbody fusion in the treatment of degenerative lumbar diseases: A protocol for systematic review and meta-analysis

Degenerative lumbar diseases are common in the aging population, and is one of the most frequent causes of disability. Lumbar fusion is an effective surgical procedure for alleviating pain and improving function. A variety of fusion techniques applied where necessary are available and the optimal method remains controversial. We performed a protocol for systematic review and meta-analysis to compare the clinical efficacy of oblique lateral interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in the treatment of degenerative lumbar diseases. This systematic review protocol will be reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols (PRISMA-P) 2015 Statement.Following databases will be searched: PubMed, web of science, MEDLINE, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese Scientific Journals Database, Wanfang data, and Chinese BioMedicine Literature Database. Only randomized controlled trials comparing OLIF and TLIF for treating degenerative lumbar diseases will be included. The meta-analysis will be performed with Review Manager Version 5.4 software (The Cochrane Collaboration, Copenhagen, Denmark). The results of this systematic review will be published in a peer-reviewed journal. This study will elucidate the clinical outcomes of OLIF compared with TLIF in treating degenerative lumbar diseases.

Factors associated with hardware failure after lateral thoracolumbar fusions – A ten year case series

ObjectiveThoracolumbar lateral interbody fusions (tLLIF) are one tool in the spine surgeon’s toolbox to indirectly decompress neuroforamina while also improving segmental lordosis in a biomechanically distinct manner from posterior fusions. When part of a concomitant posterior construct, hardware failure (HF), sometimes requiring revision surgery, can occur. We sought to study the relationship between tLLIF and HF. MethodsWe conducted a retrospective study on consecutive patents who underwent tLLIF at a single academic center between January 2012 and December 2021 by seven unique neurosurgeons. Patients were excluded if they had no posterior instrumentation within their construct or if they had less than six months of follow-up. Hardware failure was defined as screw breakage or rod fracture seen on postoperative imaging. Results232 patients were identified; 6 (2.6 %) developed HF throughout a mean follow-up of 1182 days (range =748–1647 days). Adjacent segment disease was the most common pathology addressed (75 patients (32.3 %)). The amount of posterior instrumentation both in the surgery in question and in the total construct were significantly higher in the HF cohort (4.33 ± 1.52 levels, 5.83 ± 3.36 levels) versus the non-HF cohort (2.08 ± 0.296 levels, p = 0.014; 2.86 ± 0.316 levels, p = 0.003, respectively). The number of interbody devices added in the index surgery and in the entire construct were both significantly higher in the HF cohort (3.33 ± 0.666 interbody devices, 3.33 ± 0.666 devices) than in the non-HF cohort (1.88 ± 0.152 interbody devices, p = 0.002; 2.31 ± 0.158 devices, p = 0.036, respectively). Higher amounts of lateral levels of fusion approached significance for association with HF (HF: 2.67 ± 0.844 levels, no HF: 1.73 ± 1.26 levels, p = 0.076). On multivariate analysis, only the number of interbody devices added in the index surgery was predictive of HF (Odds ratio=2.3, 95 % confidence interval=1.25–4.23, p = 0.007). ConclusionGreater levels of posterior fusion, and greater numbers of interbody devices in an index surgery and in a construct as a whole, were associated with higher rates of HF in our cohort of patients with tLLIF. Greater numbers of lateral segments fused in this population may also be related to HF.

Predictors and tactics for revision surgery in lateral lumbar interbody fusion

BackgroundThe purpose of this study is to analyze the factors affecting the revision of lateral lumbar interbody fusion (LLIF), and to summarize the complications and decision-making strategies for revision surgery after LLIF.MethodsWe retrospectively reviewed 21 cases suffered from a revision surgery after LLIF in our department from May 2017 to June 2020, with a mean follow-up of 14 months (12-25months). We collected X-ray plain films, CT (computed tomography), MRI (magnetic resonance imaging) and medical records of all patients undergoing LLIF surgery, then analyzed the reasons for revision and summarized the revision strategies in different situations. We analysed correlations between revision surgery and several factors, including age, body mass index (BMI), sex, bone quality, mode of internal fixation, spinal stenosis, postperative foraminal stenosis, disc height. Then we brought the different indicators into logistic regression to find out the risk factors of revision after LLIF. All these patients were evaluated by Quality-of-life outcomes. Univariate statistical analysis was performed using T-tests, Mann-Whitney U tests and Chi square tests.ResultsOf the 209 cases of LLIF, 21 patients underwent postoperative revision. All revision surgeries were successfully completed. The reasons for revision included vascular injury, unsatistactory implant placement, internal spinal instrumentation failure, cage migration, indirect decompression failure and infection. Indirect decompression failure was the most common indications for revision. Clinical status was apparently improved in ODI scores and VAS scores. Revision surgery did not impact long-term effect and satisfaction. Postoperative foraminal stenosis is a positive predictor for a revision surgical procedure.ConclusionPatients with postoperative foraminal stenosis are at higher risk of undergoing revision surgery after lateral lumbar interbody fusion. The correct choice of revision surgery can achieve satisfactory clinical results.

Recent Efficacy of Oblique Lateral Interbody Fusion Combined With Wiltse Approach Pedicle Screw Fixation for Degenerative Single-Level Lumbar Spondylolisthesis

The study aimed to explore the recent efficacy of oblique lateral interbody fusion (OLIF) combined with Wiltse approach pedicle screw fixation in the treatment of single-level degenerative lumbar spondylolisthesis (DLS). This is a retrospective study. The study enrolled 54 patients with single-level DLS who were treated at the Affiliated Jiangnan Hospital of Zhejiang Chinese Medical University from May 2018 to June 2020. (OLIF group) 24 cases operated using OLIF combined with Wiltse approach pedicle screw fixation, and (PLIF group) 30 cases operated by PLIF. The primary outcome measures were visual analog scale (VAS) pain scores, Oswestry dysfunction index (ODI), and the lower lumbar spine anterior convexity angle. There were significant differences in VAS (2.63±0.58 vs. 3.57±0.63, P < 0.001) and ODI (9.67±0.92 vs. 10.63±1.40, P < 0.05) between the OLIF group and PLIF group on postoperative 3days. And there was a significant decrease in VAS (2.63±0.58 vs. 1.08±0.28, P < 0.05) and ODI (3.57±0.63 vs. 1.10±0.31, P < 0.05) in both groups on postoperative 3days and at 6months postoperative comparisons. OLIF group showed better intervertebral space height and the lower lumbar spine anterior convexity angle scores on postoperative 3days and 6months, the difference was statistically significant(all P < 0.05). OLIF combined with the Wiltse approach pedicle screw fixation can achieve good short-term clinical results in the treatment of single-level DLS. This surgical approach is less invasive, promotes early functional recovery, shortens hospitalization time, and improves the quality of life.

Comparison of transfacet and pedicle screws in oblique lateral interbody fusion for single-level degenerative lumbar spine diseases: a retrospective propensity score-matched analysis

BackgroundTo perform a comparative assessment of percutaneous transfacet screws (TFS) and percutaneous bilateral pedicle screws (BPS) in oblique lateral interbody fusion (OLIF) for the treatment of single-level degenerative lumbar spine diseases in terms of radiological examinations and clinical outcomes.MethodsSixty-six patients who received single-level OLIF with percutaneous supplementary fixation assisted by the robot for the treatment of degenerative lumbar spine diseases were selected. There were 16 cases of OLIF with TFS and 50 cases of OLIF with BPS. The propensity score matching method selected 11 patients in each group with matched characteristics to perform a clinical comparison.ResultsThe estimated blood loss was 68.2 ± 25.2 ml in the OLIF with TFS group compared to 113.6 ± 39.3 ml in the OLIF with BPS group (P < 0.05). The intervertebral disc height raised from 8.6 to 12.9 mm in the TFS group and from 8.9 to 13.9 mm in the BPS group in the immediate postoperative period, and dropped to 10.8 and 12.9 mm at the twelfth month, respectively (P < 0.05). The fusion rates were 91% and 100% for TFS and BPS groups (P > 0.05). Quantitative assessments of back/leg pain of the two groups reached a healthy level in the late period of the follow-up.ConclusionBoth TFS and BPS techniques for the OLIF surgery relieve back pain caused by degenerative lumbar spine diseases. The TFS technique exhibits less blood loss compared with the BPS. A moderate cage subsidence is present in TFS but no complication is reported.

Long‐Term Clinical and Imaging Results of Oblique Lateral Interbody Fusion for Degenerative Lumbar Spondylolisthesis: A Systematic Review and Meta‐Analysis

The efficacies and safety of oblique lateral interbody fusion (OLIF) for degenerative lumbar spondylolisthesis (DLS) remains controversial, and long-term clinical efficacies in particular need to be explored. This study is designed accordingly, therefore, we searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, ProQuest, OVID, and SinoMed for literature, regardless of publication date or language. Taking 12 months after operation as the shortest limit, the outcome measures were extracted, including visual analog scale (VAS), Oswetry dysfunction index (ODI), Japanese Orthopaedic Association (JOA) score, intervertebral disk height (IDH), foraminal height (FH), lumbar lordosis (LL), segment lordosis (SL), slip ratio, and incidence of surgical complications. Meta-analysis was performed by RevMan 5.4 and Stata 16.0, and results were expressed with MD and 95% CI, and two-sided p-values with p < 0.05 being statistically significant. In total, 17 clinical studies (n=689 patients) were screened, with an average patient age of 63.4 years. Our study revealed that VAS decreased by 4.55 (low back pain) and 5.46 (leg pain) points, respectively. And ODI score decreased by an average of 33.82% while JOA score increased by an average of 11.56 points. In terms of imaging indicators, mean IDH and FH increased by 4.18 and 4.91 mm, mean LL and SL improved by 9.22° and 2.46°, respectively. Besides, mean slip ratio decreased by 10.45%. The incidence of complications was statistically analyzed in 18 studies, with a rate of 4%-54% and an overall incidence of 19%. To sum up, our study was the first to focus on the long-term efficacies of OLIF treatment for DLS, and to provide further clinical evidence. However, long-term follow-up multicenter randomized controlled trials are still needed for further evaluation.

Multicenter Prospective Study of Lateral Lumbar Interbody Fusions Using Bioactive Porous Titanium Spacers without Bone Grafts.

Prospective multicenter clinical study. To evaluate the efficacy of bioactive surface treatment for porous titanium spacers without bone graft for lateral lumbar interbody fusion (LLIF) through clinical and radiological examinations. LLIF is a minimally invasive spinal fusion procedure. To achieve bony union, a substantial volume of grafted bone is typically packed into the cage; however, this is related to donor site morbidities-one of the disadvantages of LLIF. For this prospective multicenter study, 40 patients were followed up through radiologic and clinical examinations for at least 1 year postoperatively. All surgical procedures were either single- or double-level LLIF using bioactive porous titanium spacers without bone grafts. Four patients were excluded from the study owing to aggravation from other comorbidities. Another 36 patients, including 26 and 10 with single- and double-level LLIFs, respectively, participated in the follow-up. The mean age at the time of surgery was 63.7 years. The mean operating time was 50.5 minutes per level. The mean estimated intraoperative blood loss was 11.6 mL per level. Clinical scores improved in all cases and were maintained throughout the follow-up period. The intervertebral bony union rates were 67.4% and 84.8% at 6 and 12 months, respectively. Endplate cyst signs were observed in 13.0% and 8.7% of patients at 6 and 12 months, respectively. Fused segmental angles were maintained throughout the follow-up period, indicating no cage subsidence. Single- and double-level LLIFs using bioactive porous titanium spacers without bone grafts were found to be minimally invasive, resulting in clinical and imaging results comparable with conventional procedures. Therefore, this type of implant may be an option for minimally invasive spinal fusion surgery.

Surgical outcome of minimal invasive oblique lateral interbody fusion with percutaneous pedicle screw fixation in the treatment of adult degenerative scoliosis

Oblique lateral interbody fusion is performed for lumbar spinal restoration and stabilization, without extensive paraspinal muscle damage or massive bleeding. This study aimed to confirm the radiological and clinical outcomes of minimally invasive oblique lateral interbody fusion (OLIF) with percutaneous pedicle screw fixation (PPSF) as treatment for adult degenerative lumbar scoliosis. Medical records of 40 patients with degenerative lumbar spinal deformities who underwent selective OLIF and PPSF at our hospital between April 2018 and February 2021 were retrospectively reviewed. The study population comprised 7 male and 33 female patients aged 55-79 years. Standing radiography was performed, and the coronal cobb angle, distance between the C7 plumb line and central sacral vertical line, sagittal vertical axis, pelvic tilt, lumbar lordosis (LL), pelvic incidence (PI), and difference between PI and LL (PI-LL) were measured. Coronal scoliosis was defined as a lumbar coronal plane curve of > 15°. All patients achieved statistically significant improvements in coronal and sagittal alignment. The coronal cobb angle was corrected from 18.82° to 11.52°, and the central sacral vertical line was reduced from 18.30 mm to 15.47 mm. The sagittal vertical axis was significantly reduced from 45.95 mm to 32.72 mm. In contrast, the pelvic tilt and LL were minimally changed. For subgroup analyses, patients were divided into the convex and concave groups according to the direction of coronal curve correction. Vertebral body rotation was superior in the convex group than in the concave group. Furthermore, we checked for asymmetric facet degeneration at the upper instrumented vertebra (UIV) level at 1 year postoperatively. Of the 22 patients who underwent more than 3 level fusion surgery, 8 patients were confirmed the postoperative asymmetric facet degeneration in above UIV. Minor complications occurred in 16 patients, who recovered without any problems. Revision surgery was not performed in all cases. Minimally invasive OLIF with PPSF has a lower risk of complications and favorable surgical outcomes in patients with adult degenerative lumbar scoliosis. Access from the convex side is advantageous for the correction of the rotated vertebra. Extending the UIV level to the neutral vertebra can reduce the occurrence of postoperative asymmetric facet degeneration.

Trends in Short Construct Lumbar Fusions Over the Past Decade at a Single Institution.

Retrospective cohort. (1) To compare the rates of fusion techniques over the last decade; (2) to identify whether surgeon experience affects a surgeon's preferred fusion technique; (3) to evaluate differences in complications, readmissions, mortality, and patient-reported outcomes measures (PROMs) based on fusion technique. Database studies indicate the number of lumbar fusions have been steadily increasing over the last two decades; however, insufficient granularity exists to detect if surgeons' preferences are altered based on additive surgical experience. A retrospective review of continuously collected patients undergoing lumbar fusion at a single urban academic center was performed. Rates of lumbar fusion technique: posterolateral decompression fusion (PLDF), transforaminal lumbar interbody fusion (TLIF), anterior lumbar interbody fusion + PLDF (ALIF), and lateral lumbar interbody fusion + PLDF (LLIF) were recorded. Inpatient complications, 90-day readmission, and inpatient mortality were compared with χ 2 test and Bonferroni correction. The Δ 1-year PROMs were compared with the analysis of variance. Of 3938 lumbar fusions, 1647 (41.8%) were PLDFs, 1356 (34.4%) were TLIFs, 885 (21.7%) were ALIFs, and 80 (2.0%) were lateral lumbar interbody fusions. Lumbar fusion rates increased but interbody fusion rates (2012: 57.3%; 2019: 57.6%) were stable across the study period. Surgeons with <10 years of experience performed more PLDFs and less ALIFs, whereas surgeons with >10 years' experience used ALIFs, TLIFs, and PLDFs at similar rates. Patients were more likely to be discharged home over the course of the decade (2012: 78.4%; 2019: 83.8%, P <0.001). No differences were observed between the techniques in regard to inpatient mortality ( P =0.441) or Δ (postoperative minus preoperative) PROMs. Preferred lumbar fusion technique varies by surgeon preference, but typically remains stable over the course of a decade. The preferred fusion technique did not correlate with differences in PROMs, inpatient mortality, and patient complication rates. 3-treatment.

Long-Term Motor versus Sensory Lumbar Plexopathy After Lateral Lumbar Interbody Fusion: Single-Center Experience, Intraoperative Neuromonitoring Results, and Multivariate Analysis of Patient-Level Predictors

Although lateral lumbar interbody fusion (LLIF) is an effective surgical option for lumbar arthrodesis, postoperative plexopathies are a common complication. We characterized post-LLIF plexopathies in a large cohort and analyzed potential risk factors for each. A single-institutional cohort who underwent LLIF between May 2015 and December 2019 was retrospectively reviewed for postoperative lumbar plexopathies. Plexopathies were divided based on sensory and motor symptoms and duration, as well as by laterality relative to the surgical approach. We assessed these subgroups for associations with patient and surgical characteristics as well as psoas dimensions. We then evaluated risk of developing plexopathies after intraoperative neuromonitoring observations. A total of 127 patients were included. The overall rate of LLIF-induced sensory or motor lumbar plexopathy was 37.8% (48/127). Of all cases, 42 were ipsilateral to the surgical approach (33.1%); conversely, 6 patients developed contralateral plexopathies (4.7%). Most (31/48; 64.6%) resolved with a follow-up interval of 402 days in the plexopathy group. Of ipsilateral cases, 24 patients experienced persistent (>90 days) postoperative sensory symptoms (18.9%), whereas 20 experienced persistent weakness (15.7%). More levels fused predicted persistent sensory symptoms (odds ratio, 1.714 [1.246-2.359]; P= 0.0085), whereas surgical duration predicted persistent weakness (odds ratio, 1.004 [1.002-1.006]; P= 0.0382). Psoas anatomic variables were not significantly associated with plexopathy. Nonresolution of intraoperative evoked motor potential alerts was a significant risk factor for developing plexopathies (relative risk, 2.29 [1.17-4.45]). Post-LLIF plexopathies are common but usually resolve. Surgical complexity and unresolved neuromonitoring alerts are possible risk factors for persistent plexopathy.

Risk factors for nonunion in oblique lateral interbody fusion

BackgroundCompared with posterior interbody fusion techniques, oblique lateral interbody fusion (OLIF) offers a larger fusion bed with greater intervertebral space access, use of larger cages, more sufficient discectomy, and better end-plate preparation. However, the fusion rate of OLIF is similar to that of other interbody fusions. This study aimed to examine the factors associated with nonunion in OLIF. MethodsThis study examined 201 disc levels from 124 consecutive patients who underwent OLIF for lumbar degenerative diseases with 1-year regular follow-up. Demographic and surgical factors were reviewed from the medical records. Radiological factors measured were sagittal parameters, intervertebral disc angle (DA) before surgery and at the final follow-up, presence of vertebral end-plate lesions, and cage subsidence. Multivariable logistic regression analysis was performed to identify the factors associated with nonunion. ResultsAmong the 201 discs, 185 (92.0%) achieved union at 1-year followed up. Smoking, surgery at the L5-S1 level, not performing laminectomy, and a large intervertebral DA were factors associated with nonunion in OLIF (all P < 0.05). Multivariable logistic regression analysis showed two independent variables (surgery at L5-S1 level and not performing laminectomy) as risk factors for nonunion in OLIF. ConclusionsNot performing laminectomy and surgery at the L5-S1 level were risk factors for nonunion in OLIF. To reduce the nonunion rate, surgeons should consider additional stabilization strategies for the L5-S1 OLIF and perform laminectomy.

Biomechanical Performances of an Oblique Lateral Interbody Fusion Cage in Models with Different Bone Densities: A Finite Element Analysis.

Finite element models of the L3-S1 vertebrae were reconstructed using computed tomography scans. We compared the biomechanical performances of an oblique lateral interbody fusion (OLIF) cage in different bone density mode. Low bone density is an els.key factor limiting the use of stand-alone OLIF cage. Four models-intact (M0), normal bone density with OLIF (M1), bone mass loss with OLIF (M2), and osteoporotic with OLIF (M3)-were created based on 3-dimensional scans. Flexion, extension, and lateral bending movements (each lasting 10N·m) were performed on the superior surface of the L3 vertebra with a compressive preload of 500N. Range of motion (ROM), peak stresses in the L4-5 cortical endplates, cage stress, and adjacent intervertebral disk stress were evaluated. ROMs during different physiological movements were similar to those reported by previous researchers. Compared with that in M0, L4-5 ROMs of all movements decreased in M1, M2 and M3, most evidently in M3. Stress distribution in the cortical endplates rose to 7.8% in M1 and M2, even 16.2% in M3. Cage stress increased by less than 8.1% in M1 and M2, but by 25.3% in M3, especially in the movements of extension and right rotation. Compared with that in M0, L3-4 and L5-S1 intervertebral disk stress increased with bone density in all the other models, by up to 69.8% and 98.3%, respectively. As osteoporosis worsened, stress in the adjacent intervertebral disk also increased. Stand-alone OLIF in M3 is not recommended because of the risk of cage subsidence. OLIF in M1 and M2 achieved similar results in various lumbar spine movements. In M1 and M2 model (T > - 2.5), the L4-L5 showed reduced mobility in all directions, increased rigidity, limited cage displacement, lessened deformation, and better stability.