Lateral Lumbar Interbody Fusion Group Research Articles

474 Comparing the Reciprocal Changes of Single Level Transforaminal Interbody Fusions Versus Lateral Interbody Fusions: A Radiographic Analysis for Sagittal Alignment and Spinopelvic Parameters

INTRODUCTION: Transforaminal lumbar interbody fusion (TLIF) and lateral lumbar interbody fusion (LLIF) are two techniques that are widely used to treat single-level pathology at L4-5. To date, no studies have compared the two techniques in terms of their ability to address disc space pathology, such as loss of height and spondylolisthesis, and achieve spinopelvic alignment goals. METHODS: After IRB approval, this study retrospectively reviewed the records of 203 patients who underwent single-level L4-L5 TLIFs and single-level L4-L5 LLIFs between 2017 to 2022. Preoperative and postoperative scoliosis films were collected and analyzed using an automated calibrated radiographic tool to measure pre-postoperative SA and SPs. Two blinded readers measured the pre-postoperative variables. Independent Sample T-tests were used to analyze the radiographic outcomes between the two groups. RESULTS: This study evaluated the results of 203 single-level TLIFs and LLIFs (109 L4-L5 TLIFs, and 94 L4-L5 LLIFs). Among the surgeries analyzed, 90 were MIS TLIFs, 19 open TLIFs, 16 standalone LLIs, and 78 LLIFs with posterior instrumentation. Postoperative scoliosis films were taken at a median of 0.28 (± 0.4) months. The analysis focused on comparing the reciprocal changes between both procedures. Significant statistical differences was found for ΔGTilt (p = 0.036), ΔLPA (p = 0.12), ΔADH (p = 0.03), ΔPDH (p = 0.04), ΔFH (p = 0.001), and ΔS% (p = 0.01) in the LLIF group, among all the variables included in the analysis. CONCLUSIONS: L4-5 LLIF and TLIF resulted in statistically similar amounts of lordosis restoration and reciprocal change at proximal and distal lumbar levels. LLIF was found to be superior in restoration of anterior disc height, posterior disc height, and foraminal height compared to TLIF. LLIF was also superior in percentage reduction of spondylolisthesis.

A Comparison of Hidden Blood Loss Between Multilevel Posterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion in Adult Spinal Deformity Patients.

Retrospective cohort study. This study aimed to compare transfusion and blood loss volumes, particularly hidden blood loss volume, in adult spinal deformity patients undergoing lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF). Corrective surgery for adults with spinal deformity patients can be performed via the traditional posterior approach (PLIF) or minimally invasive lateral approach (LLIF). LLIF is associated with longer or comparable operation times and lower intraoperative blood loss. However, hidden blood loss has not been compared between the two procedures. We compared hidden blood loss and other blood loss volumes, transfusion volume, operation time, and radiographic surgical outcomes between LLIF patients (n = 71) and PLIF patients (n = 33) who underwent surgery in our institution from September 2011 to June 2018. All patients provided informed consent in accordance with the Declaration of Helsinki. Institutional ethics committee conducted this study approval was obtained. Transfusion volume and intraoperative and total blood loss volumes were significantly higher in the PLIF group. Operation time and HBL did not significantly differ. The hidden blood loss-to-intraoperative blood loss ratio was significantly higher in the LLIF group (113% vs 60%; P = .004). Radiographic measures of outcome were significantly better after surgery than before in both groups. Although intraoperative blood loss was less with LLIF than PLIF, HBL was similar between the approaches. Patients undergoing LLIF should be followed closely for postoperative anemia even if intraoperative blood loss is low.

Comparison of Intraoperative Endplate Injury between Mini-Open Lateral Lumbar Interbody Fusion (LLIF) and Transforaminal Lumbar Interbody Fusion (TLIF) and Analysis of Risk Factors: A Retrospective Study

Objective The study aimed to compare the incidence of intraoperative endplate injury in patients who underwent Transforaminal interbody fusion (TLIF) and mini-open lumbar interbody fusion (LLIF) surgery. The independent risk factors related to endplate injury in LLIF procedure were analyzed. Methods A total of 199 patients who underwent LLIF (n = 106) or TLIF (n = 93) surgery from June 2019 to September 2021 were reviewed. The endplate injury was assessed by postoperative sagittal CT scan. A binary logistic analysis model were used to identify independent risk factors related to LLIF endplate injury based on univariate analysis. Results There was an obvious difference in the occurrence of intraoperative endplate injury between LLIF (42/106, 39.6%) and TLIF group (26/93, 28%), although it did not reach the significant level. L1 CT value (OR = 0.985, 95% CI = 0.972–0.998), cage position (OR = 3.881, 95% CI = 1.398–10.771) and height variance (OR = 1.263, 95% CI = 1.013–1.575) were independent risk factors for endplate injury in LLIF procedure. According to the cage settlement patterns, there 5 types of A to E. The severity of the facet joint degeneration was positively related to the occurrence of endplate injury. Conclusions The incidence of intraoperative endplate injury is higher in LLIF than in TLIF procedures. Low bone quantity, cage posterior position and larger height variance are risk factors to induce endplate injury in LLIF surgery. The facet joint degeneration may be related to severe endplate injuries and even fractures.

Early Experiences With Single-Position Prone Lateral Lumbar Interbody Fusion: Safety and Outcomes

Background: Performing lateral lumbar interbody fusion (LLIF) in a single prone position may pose many advantages over the traditional lateral decubitus position, but there are questions concerning its safety profile and outcomes. Purpose: We sought to study the safety and efficacy of LLIF performed with the patient in the prone position. Methods: We conducted a retrospective cohort study including patients who underwent primary LLIF in the prone position for degenerative lumbar conditions. Complications and patient-reported outcome measures (PROMs) (Oswestry Disability Index [ODI], and visual analogue scale [VAS] scores for leg and back pain) were collected. Patients who underwent single-position prone LLIF were then propensity score matched for age, race, comorbidity index, number of levels, body mass index, and smoking status with patients who underwent single-position lateral LLIF. Patient-reported outcome measures and complications were compared between the 2 groups. Two postoperative timepoints were defined: early (<6 months) and late (≥6 months). Results: Twenty single-position prone LLIF patients were included (35% 1-level, 35% 2-level, 15% 3-level, and 15% 4-level). No intraoperative complications were reported. Eleven (55%) patients experienced transient postoperative anterior thigh weakness. Five (25%) patients experienced postoperative complications such as anemia, urinary retention, ileus, and new-onset sensory symptoms. Oswestry Disability Index, VAS leg, and VAS back scores all improved at the >6-month time point compared with preoperative states. There were no significant differences at any postoperative time point for PROMs between prone and lateral LLIF groups. Among the matched cohort, complications were observed in 3 (21%) of patients compared with only 1 (7%) in the lateral group although this difference was not statistically significant. Conclusion: This retrospective study suggests that prone LLIF procedures may be safe and effective. Ergonomic and logistic benefits from the approach may make it a beneficial approach for surgeons to begin implementing.

Comparison of PLIF/TLIF and LLIF for two-level degenerative lumbar spondylolisthesis

IntroductionIn recent years, lateral lumbar interbody fusion (LLIF), performed as extreme lateral interbody fusion (XLIF) and oblique lateral interbody fusion (OLIF), has also become widely used for anterior-posterior corrective fusion. However, there are few detailed reports comparing techniques in the treatment of two-level degenerative spondylolisthesis. We compared the surgical invasiveness and postoperative outcomes between posterior interbody fusion with posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF) and LLIF for two-level lumbar degenerative spondylolisthesis. MethodsFifteen patients underwent PLIF or TLIF at 2 vertebral intervals (posterior group) and 8 patients received XLIF or OLIF (LLIF group). The following parameters were examined: operative time, blood loss, preoperative %slip, preoperative sagittal parameters, postoperative %slip, postoperative 1-year %slip, postoperative 1-year sagittal parameters, bone fusion rate at 1 year postoperatively, pre- and postoperative visual analog scale scores, pre- and postoperative Japanese Orthopaedic Association (JOA) scores, and complications. ResultsIn the LLIF group, blood loss was significantly lower and operative time was shorter than in the posterior group. There were no significant differences for 1-year postoperative %slip, sagittal vertical axis, or lumbar lordosis, although the frequency of cases with a 1-year postoperative pelvic incidence (PI)-LL ≤ 10 degrees was significantly higher in the LLIF group. In both groups, JOA scores were improved significantly at 1 year postoperatively (both p < 0.01), with no remarkable difference in improvement rate between the groups (p = 0.09). ConclusionsLLIF was less invasive, comparably effective, and more preserving of global spinal balance in correcting two-level degenerative spondylolisthesis than conventional posterior interbody fusion.

Comparison of segmental lordosis gain of prone transpsoas (PTP) vs. lateral lumbar interbody fusion.

Lumbar interbody fusion is a standard method to treat certain degenerative conditions that are refractory to conservative treatments. LLIF reduces posterior muscle damage, can relieve neurological symptoms through indirect decompression, provides increased stability with its wider cages, and promotes more significant segmental lordosis than standard posterior techniques. However, the technique possesses its issues, such as unusual positioning, possible plexus-related symptoms, and median segmental lordosis correction. Trying to ease those issues, the idea of a prone transpsoas technique occurred. Retrospective, single-centric, comparative, and non-randomized study. The authors paired patients receiving lateral lumbar interbody fusion (LLIF) or prone transpsoas (PTP) to evaluate the technique's impact on the segmental lordosis correction. A correlation test selected the covariates for the matching. p-Values inferior to 0.05 were deemed significant. Seventy-one patients were included in the analysis, 53 in the LLIF group and 18 in the PTP group. The significant covariates to the segmental lordosis correction were technique, preoperative segmental lordosis, cage position, and preoperative pelvic tilt. After the paring model, PTP showed significant segmental lordosis correction potential regarding the LLIF. The prone transpsoas approach can significantly enhance the correction of segmental lordosis proportionated to the traditional LLIF approach.

Lateral lumbar interbody fusion (LLIF) reduces total lifetime cost compared with posterior lumbar interbody fusion (PLIF) for single-level lumbar spinal fusion surgery: a cost-utility analysis in Thailand

BackgroundLumbar interbody fusion techniques treat degenerative lumbar diseases effectively. Minimally invasive lateral lumbar interbody fusion (LLIF) decreases soft tissue disruption and accelerates recovery better than standard open posterior lumbar interbody fusion (PLIF). However, the material cost of LLIF is high, especially in Thailand. The cost-effectiveness of LLIF and PLIF in developing countries is unclear. This study compared the cost-utility and clinical outcomes of LLIF and PLIF in Thailand.MethodsData from patients with lumbar spondylosis who underwent single-level LLIF and PLIF between 2014 and 2020 were retrospectively reviewed. Preoperative and 1-year follow-up EuroQol-5D-5L and healthcare costs were collected. A cost-utility analysis with a lifetime time horizon was performed using a societal perspective. Outcomes are reported as the incremental cost-effectiveness ratio (ICER) and quality-adjusted life-year (QALY) gained. A Thai willingness-to-pay threshold of 5003 US dollars (USD) per QALY gained was used.ResultsThe 136 enrolled patients had a mean age of 62.26 ± 11.66 years. Fifty-nine patients underwent LLIF, while 77 underwent PLIF. The PLIF group experienced greater estimated blood loss (458.96 vs 167.03 ml; P < 0.001), but the LLIF group had a longer operative time (222.80 vs 194.62 min; P = 0.007). One year postoperatively, the groups’ Oswestry Disability Index and EuroQol-Visual Analog Scale scores were improved without statistical significance. The PLIF group had a significantly better utility score than the LLIF group (0.89 vs 0.84; P = 0.023). LLIF’s total lifetime cost was less than that of PLIF (30,124 and 33,003 USD). Relative to PLIF, LLIF was not cost-effective according to the Thai willingness-to-pay threshold, with an ICER of 19,359 USD per QALY gained.ConclusionsLLIF demonstrated lower total lifetime cost from a societal perspective. Regard to our data, at the 1-year follow-up, the improvement in patient quality of life was less with LLIF than with PLIF. Additionally, economic evaluation modeling based on the context of Thailand showed that LLIF was not cost-effective compared with PLIF. A strategy that facilitates the selection of patients for LLIF is required to optimize patient benefits.

71. Navigated lateral lumbar interbody fusion (LLIF) leads to decreased radiation exposure compared to fluoroscopy

BACKGROUND CONTEXT Reducing fluoroscopy time and radiation exposure in the operating room is beneficial for the patient and surgical team. Placement of an interbody device during lateral transpsoas approach is traditionally carried out using anterior-posterior and lateral fluoroscopy. In this setting, 3-dimensional computed tomography (CT)-based spinal navigation of cage and pedicle screw/rod placement for LLIF procedure may result in decreased radiation exposure compared with fluoroscopically-guided LLIF. We sought to present our experience with the use of CT-based spinal navigation for the LLIF procedure and evaluate rates of intraoperative complications and radiation exposure. PURPOSE To determine if computer-navigation guided LLIF will have equivalent outcomes with decreased radiation dose compared to fluoroscopy-guided LLIF. STUDY DESIGN/SETTING Single-center retrospective review. PATIENT SAMPLE This study included 250 patients over 18 years of age who underwent LLIF with <4 levels fused (age: 61.4 ± 10.8 yrs, BMI: 29.7 ± 6.1 7 kg/m²). OUTCOME MEASURES Intraoperative and 90-day complications, radiation exposure and cage placement. METHODS Patients were separated into two groups: fluoroscopy-guided LLIF (n=224), and navigated LLIF (n=26). Cage placement was assessed on postoperative radiographs by dividing the disc space into quarters, anterior to posterior. RESULTS In terms of operative characteristics, fluoroscopy dosage was significantly greater in the fluoroscopically-guided LLIF cohort (55.1 ± 57.4 mGy vs 34.0 ± 24.9 mGy, p=0.002). There were no significant differences between fluoroscopically-guided LLIFs and navigated LLIFs in overall intraoperative complication rate (4% Fluoro vs 0% Nav, p=0.3), rate of durotomy (2.2 % Fluoro vs 0% Nav, p=0.44), or estimated blood loss (322 ± 330.3 cc Flouro vs 299.5 ± 198.6 cc Nav, p=0.6). The rate of postoperative complications (26.8% Fluoro vs 26.9% Nav), neurologic complications (5.4% Fluoro vs 3.8% Nav), surgical site infections (1.3% Fluoro vs 3.8% Nav), mechanical complications (1.8% Fluoro vs 0% Nav) was not significantly different. There was no significant difference in the rate of unplanned return to the operating room within 90 days (1.8% Fluoro vs 0% Nav). Cage placement was similar between the two groups (p=0.29). CONCLUSIONS We report an average radiation exposure with navigated LLIFs of 34.0 mGy, significantly lower than the 55.1 mGy in the fluoroscopically-guided LLIF group. The length of stay and perioperative complication rate was equivalent between the groups. These data support the use of CT-based navigation for placement of the cage and pedicle screws/rod construct for LLIF procedure. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. Reducing fluoroscopy time and radiation exposure in the operating room is beneficial for the patient and surgical team. Placement of an interbody device during lateral transpsoas approach is traditionally carried out using anterior-posterior and lateral fluoroscopy. In this setting, 3-dimensional computed tomography (CT)-based spinal navigation of cage and pedicle screw/rod placement for LLIF procedure may result in decreased radiation exposure compared with fluoroscopically-guided LLIF. We sought to present our experience with the use of CT-based spinal navigation for the LLIF procedure and evaluate rates of intraoperative complications and radiation exposure. To determine if computer-navigation guided LLIF will have equivalent outcomes with decreased radiation dose compared to fluoroscopy-guided LLIF. Single-center retrospective review. This study included 250 patients over 18 years of age who underwent LLIF with <4 levels fused (age: 61.4 ± 10.8 yrs, BMI: 29.7 ± 6.1 7 kg/m²). Intraoperative and 90-day complications, radiation exposure and cage placement. Patients were separated into two groups: fluoroscopy-guided LLIF (n=224), and navigated LLIF (n=26). Cage placement was assessed on postoperative radiographs by dividing the disc space into quarters, anterior to posterior. In terms of operative characteristics, fluoroscopy dosage was significantly greater in the fluoroscopically-guided LLIF cohort (55.1 ± 57.4 mGy vs 34.0 ± 24.9 mGy, p=0.002). There were no significant differences between fluoroscopically-guided LLIFs and navigated LLIFs in overall intraoperative complication rate (4% Fluoro vs 0% Nav, p=0.3), rate of durotomy (2.2 % Fluoro vs 0% Nav, p=0.44), or estimated blood loss (322 ± 330.3 cc Flouro vs 299.5 ± 198.6 cc Nav, p=0.6). The rate of postoperative complications (26.8% Fluoro vs 26.9% Nav), neurologic complications (5.4% Fluoro vs 3.8% Nav), surgical site infections (1.3% Fluoro vs 3.8% Nav), mechanical complications (1.8% Fluoro vs 0% Nav) was not significantly different. There was no significant difference in the rate of unplanned return to the operating room within 90 days (1.8% Fluoro vs 0% Nav). Cage placement was similar between the two groups (p=0.29). We report an average radiation exposure with navigated LLIFs of 34.0 mGy, significantly lower than the 55.1 mGy in the fluoroscopically-guided LLIF group. The length of stay and perioperative complication rate was equivalent between the groups. These data support the use of CT-based navigation for placement of the cage and pedicle screws/rod construct for LLIF procedure.

Comparison of Minimally Invasive Lateral Lumbar Interbody Fusion, Minimally Invasive Lateral Lumbar Interbody Fusion, and Open Posterior Lumbar Interbody Fusion in the Treatment of Single-Level Spondylolisthesis of L4-L5

To compare the outcomes of minimally invasive lateral lumbar interbody fusion (LLIF) with minimally invasive transforaminal lumbar interbody fusion (TLIF) and conventional open posterior lumbar interbody fusion (PLIF) for treating single-level spondylolisthesis at L4-L5. The patients underwent minimally invasive LLIF (n= 18), minimally invasive TLIF (n= 17), and conventional open PLIF (n= 20) for spondylolisthesis at L4-L5. Reduction of slippage, improvement in segmental lordosis, and restoration of foraminal height were measured. Perioperative parameters such as blood loss and operation time and clinical outcomes such as visual analog scale score and Oswestry Disability Index were compared. Compared with the open PLIF group, the minimally invasive LLIF group showed greater restoration of mean foraminal height, significantly smaller mean intraoperative estimated blood loss, and less mean hemoglobin reduction on the third day postoperatively. Compared with the minimally invasive TLIF group, the minimally invasive LLIF group showed greater restoration of mean segmental lordosis. The minimally invasive LLIF group showed a significantly shorter mean time to start walking after surgery compared with the conventional open PLIF and minimally invasive TLIF groups. However, compared with the minimally invasive TLIF group, the minimally invasive LLIF group showed a significantly longer mean operating time. Clinical outcomes were not statistically different among the 3 groups. In the treatment of spondylolisthesis of L4-L5, minimally invasive LLIF provided an effective surgical alternative to minimally invasive TLIF or conventional open PLIF, with the advantages of less blood loss, the faster start of postoperative walking, and comparable improvement in radiologic parameters.

Cost-effectiveness of Corrective Fusion Surgeries for Adult Spinal Deformities: A Comparison by Operative Method.

Retrospective cohort study. The aim of this study was to summarize the cost-effectiveness of surgical treatment for adult spinal deformity (ASD) according to the operative method over 2 years postoperatively. Extensive corrective fusion surgery for ASD requires numerous expensive implants, greatly contributing toward the national medical expenses. Previous national studies reported high complication rates in spinal surgeries using instrumentation. However, the cost-effectiveness of such procedures has not been scrutinized. In total, 173 ASD patients (151 women; mean age 69.1 years) who underwent corrective fusion between 2010 and 2017 were included. Cost-effectiveness was evaluated according to the cost of obtaining 1 quality-adjusted life year (QALY). Patients were divided into three groups: the "corrective fusion surgery using multiple Grade 2 osteotomy" (Grade-2) group, three-column osteotomy group (three-column), and lateral lumbar interbody fusion (LLIF) group. The average medical cost for the initial surgery was USD 72,240, and that during the 2 years after the initial surgery was USD 76,294. The medical expenses for the initial surgery and those over the 2 years were higher in the LLIF group. The cumulative improvement in QALY over the 2 years did not significantly differ among the groups (0.13, 0.15, and 0.18 in the Grade-2, three-column, and LLIF groups, respectively). Cost/QALY 2 years after the surgery was USD 509,370, 518,406, and 463,798 in the Grade-2, three-column, and LLIF groups, respectively. We summarized the medical costs and cost-effectiveness of three different surgical methods for ASD in patients with different backgrounds over 2 years postoperatively. The medical expense for the initial surgery was highest in the LLIF group, and the cumulative improvement in QALY over the 2 years tended to be higher in the LLIF group, but the difference was not significant; the overall cost-effectiveness was lowest in the LLIF group.Level of Evidence: 3.

Lateral lumbar interbody fusion in revision surgery for restenosis after posterior decompression.

The purpose of this study was to compare the clinical results of revision interbody fusion surgery between lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF) with propensity score (PS) adjustments and to investigate the efficacy of indirect decompression with LLIF in previously decompressed segments on the basis of radiological assessment. A retrospective study of patients who underwent revision surgery for recurrence of neurological symptoms after posterior decompression surgery was performed. Postoperative complications and operative factors were evaluated and compared between LLIF and PLIF/TLIF. Moreover, postoperative improvement in cross-sectional areas (CSAs) in the spinal canal and intervertebral foramen was evaluated in LLIF cases. A total of 56 patients (21 and 35 cases of LLIF and PLIF/TLIF, respectively) were included. In the univariate analysis, the LLIF group had significantly more endplate injuries (p = 0.03) and neurological deficits (p = 0.042), whereas the PLIF/TLIF group demonstrated significantly more dural tears (p < 0.001), surgical site infections (SSIs) (p = 0.02), and estimated blood loss (EBL) (p < 0.001). After PS adjustments, the LLIF group still showed significantly more endplate injuries (p = 0.03), and the PLIF/TLIF group demonstrated significantly more dural tears (p < 0.001), EBL (p < 0.001), and operating time (p = 0.04). The PLIF/TLIF group showed a trend toward a higher incidence of SSI (p = 0.10). There was no statistically significant difference regarding improvement in the Japanese Orthopaedic Association scores between the 2 surgical procedures (p = 0.77). The CSAs in the spinal canal and foramen were both significantly improved (p < 0.001). LLIF is a safe, effective, and less invasive procedure with acceptable complication rates for revision surgery for previously decompressed segments. Therefore, LLIF can be an alternative to PLIF/TLIF for restenosis after posterior decompression surgery.

Surgical Outcomes of Multilevel Posterior Lumbar Interbody Fusion versus Lateral Lumbar Interbody Fusion for the Correction of Adult Spinal Deformity: A Comparative Clinical Study

Study DesignA retrospective case control study.PurposeThe purpose of this study was to compare the surgical outcomes of multilevel lateral lumbar interbody fusion (LIF) and multilevel posterior lumbar interbody fusion (PLIF) in the surgical treatment of adult spinal deformity (ASD) and to evaluate the sagittal plane correction by combining LIF with posterior-column osteotomy (PCO).Overview of LiteratureThe surgical outcomes between multilevel LIF and multilevel PLIF in ASD patients remain unclear.MethodsWe retrospectively reviewed 31 ASD patients who underwent multilevel LIF combined with PCO (LIF group, n=14) or multilevel PLIF (PLIF group, n=17) and with a minimum 2-year follow-up. In the comparison between LIF and PLIF groups, their mean age at surgery was 69.4 vs. 61.8 years while the mean follow-up period was 29.2 vs. 59.3 months. We evaluated the transition of pelvic incidence–lumbar lordosis (PI–LL) and disc angle (DA) in the LIF group, in fulcrum backward bending (FBB), after LIF and after posterior spinal fusion (PSF) with PCO. The spinopelvic radiographic parameters were compared between LIF and PLIF groups.ResultsCompared with the PLIF group, the LIF group had less blood loss and comparable surgical outcomes with respect to radiographic data, health-related quality of life scores and surgical time. In the LIF group, the mean DA and PI–LL were unchanged after LIF (DA, 5.8°; PI–LL, 15°) compared with the values using FBB (DA, 4.3°; PI–LL, 15°) and improved significantly after PSF with PCO (DA, 8.1°; PI–LL, 0°).ConclusionsIn the surgical treatment of ASD, multilevel LIF is less invasive than multilevel PLIF and combination of LIF and PCO would be necessary for optimal sagittal correction in patients with rigid deformity.

Patient-reported Quality of Life Following Posterior Lumbar Interbody Fusion or Indirect Decompression Using Lateral Lumbar Interbody Fusion.

A retrospective review of prospectively collected data. The aim of this study was to compare quality of life (QOL) outcomes of posterior lumbar interbody fusion (PLIF) with lateral lumbar interbody fusion (LLIF) using reports from patients obtained at the 2-year postoperative follow-up. Indirect decompression with LLIF is used to treat degenerative lumbar diseases that require neural decompression. However, the difference in improvement in QOL following indirect decompression compared with direct neural decompression using PLIF is unclear. We enrolled 284 consecutive patients with degenerative lumbar spondylolisthesis in the present study, 203 who underwent PLIF and 81 who underwent LLIF. All patients completed a minimum of 2 years of follow-up. We evaluated the effectiveness of surgery in each category of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). The results of preoperative JOABPEQ and the severity of thecal sac stenosis were not significantly different between PLIF and LLIF, neither was the rate of perioperative complications (14.8% and 15.4% for the PLIF and LLIF groups, respectively; P = 0.91). The effectiveness at 2 years postoperatively was almost the same for all five domains of the JOABPEQ: 62.6% and 68.9% for pain-related disorders (P = 0.34), 38.3% and 42.7% for lumbar spine dysfunction (P = 0.51), 65.8% and 67.5% for gait disturbance (P = 0.79), 53.5% and 48.8% for social life dysfunction (P = 0.47), and 29.1% and 33.3% for psychological disorders (P = 0.48) following PLIF and LLIF, respectively. Visual analogue scale results for back and lower-limb pain and numbness of the lower limbs were almost the same for both groups. No significant differences were observed in terms of perioperative complications and radiographical outcomes. Indirect decompression using LLIF improves QOL and radiographical outcomes to a comparable degree as direct decompression via PLIF. 4.

Indirect Decompression Using Lateral Lumbar Interbody Fusion for Restenosis after an Initial Decompression Surgery.

Study DesignRetrospective comparative study.PurposeWe compared clinical and radiographical outcomes after lumbar decompression revision surgery for restenosis by lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF).Overview of LiteratureIndirect lumbar decompression with LLIF was used to treat degenerative lumbar diseases requiring neural decompression. However, only a few studies have focused on the effectiveness of this technique for restenosis after lumbar decompression.MethodsWe retrospectively investigated 52 cases involving lumbar interbody fusions for restenosis with spondylolisthesis after lumbar decompressions; these cases consisted of 15 patients who underwent indirect decompression with LLIF and posterior fixation and 37 patients who underwent the same procedure with PLIF. We compared Japanese Orthopaedic Association (JOA) scores and perioperative complications between groups. The cross-sectional areas of the thecal sac on magnetic resonance imaging were measured before, immediately after, and 2 years after surgery. We conducted statistical analyses using unpaired t -test and Fisher’s exact tests, and a p-value <0.05 was considered statistically significant.ResultsThe operative time was significantly shorter in the LLIF group than in the PLIF group (115.3±33.6 min vs. 186.2±34.2 min, respectively; p<0.001). In addition, the intraoperative blood loss was significantly lower in the LLIF group than in the PLIF group (58.2±32.7 mL vs. 303.2±140.1 mL, respectively; p<0.001). We found two cases of transient lateral thigh weakness (13.3%) in the LLIF group and five cases of incidental durotomy, one case of deep infection, and one case of neurological deterioration in the PLIF group—resulting in a higher complication incidence (18.9%), although it did not reach (p=0.63). The JOA scores improved significantly in both groups.ConclusionsIndirect decompression using LLIF provided acceptable clinical and radiographical outcomes in patients with restenosis with spondylolisthesis after lumbar decompression; no revision-surgery-specific complications were found. Our results suggest that LLIF is a safe and minimally invasive procedure for revision surgery.

260. How much lordosis can be restored by minimally invasive multilevel lateral lumbar interbody fusion combined with posterior column osteotomy using stiff rod (6.35 mm cobalt chrome) in adult spinal deformity surgery?

BACKGROUND CONTEXT Pedicle subtration osteotomy (PSO) is highly effective as a method for sagittal correction in patients with adult spinal deformity, but there are issues such as surgical complexity and long-term complications. Although, recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity, few reports have directly compared it with PSO. PURPOSE The purpose of this study was to evaluate the radiological and clinical efficacies of lateral lumbar interbody fusion (LLIF) combined with posterior column osteotomy (PCO) using stiff rod (6.35 mm Cobalt Chrome; CoCr). STUDY DESIGN/SETTING Retrospective, consecutive case review. PATIENT SAMPLE A total of 106 patients (average age 71.5 years) who were diagnosed adult spinal deformity with sagittal imbalance and followed up for more than 2 years after sagittal correction OUTCOME MEASURES Description and analysis of X-ray and clinical questionaires (Oswestry Disability Index, Visual Analogie Scale) METHODS Comparative analysis was performed on the spinopelvic parameters and clinical outcomes of patients who underwent PSO (PSO group; n=65) and the patients who underwent multilevel pre-psoas LLIF combined with PCO and open posterior spinal fusion using 6.35 mm Cobalt Chrome rod (LLIF group; n=41). RESULTS There were no differences in preoperative spinopelvic parameters between PSO group and LLIF group. Although there were no differences between the two groups in terms of postoperative SVA (-12.7 mm vs -16.5 mm), postoperative lumbar lordosis (-71.5° vs -72.6°), lumbar lordosis correction (78.0°vs 73.5°), sacral slope (46.3° vs 49.1°) and pelvic tilt (9.4° vs 7.2°), estimated blood loss was significantly lower in the LLIF group (2,824 ml vs 1,736 ml, P=0.000). No differences were observed in the clinical outcomes (Oswestry Disability Index, Visual Analog Scale), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after the surgery, but reoperation due to pseudarthrosis was significantly higher in the PSO group (P=0.004). CONCLUSIONS Minimally invasive multilevel LLIF combined with PCO using a stiff rod leads to better clinical and radiological outcomes as much as PSO, accompanied by fewer long-term major complications, such as pseudarthrosis and reoperation. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

206. Does ACR result in greater morbidity than LLIF alone when treating adult spinal deformity?

BACKGROUND CONTEXT Anterior column realignment (ACR) can be utilized for correction of adult spinal deformity (ASD), but the additional benefit over lateral lumbar interbody fusion (LLIF) alone is unclear. PURPOSE To evaluate the relative impact of ACR vs LLIF on clinical and radiographic outcomes, as well as complication rates, when surgically treating ASD. STUDY DESIGN/SETTING Prospective multicenter database review. PATIENT SAMPLE A total of 127 patients. OUTCOME MEASURES Oswestry Disability Index (ODI), visual analog score (VAS), SRS-22. METHODS Inclusion criteria were age ≥18 years, and one of the following: coronal cobb>20°, SVA>5cm, PT>20°, PI-LL >10°. Patients were treated with circumferential MIS (cMIS) surgery or hybrid MIS surgery, underwent LLIF (LLIF group) or ACR/LLIF (ACR group) and had 1-year minimum follow-up. RESULTS A total of 127 patients met inclusion criteria, 101 underwent LLIF and 26 had ACR. Average age and BMI were 66.3/27.7 and 67.8/27.4 (p=0.654/0.957). The groups had similar rates of prior spine surgery (48.5% vs 57.7%; p=0.403), cMIS (58.7% vs 73.1%; p=0.222), posterior osteotomies (43.6% vs 34.6%; p=0.409), levels instrumented (7.8 vs 8; p=0.895), and interbody fusion levels (3.4 vs 3.6; p=0.478). Preop and postop spinopelvic parameters were similar between groups, except for postop SVA which was higher in the LLIF group (40mm vs 13mm; p = 0.028). One year PI-LL (3.8 vs 5.8; p=0.555), PT (20.6 vs 22.9;p=0.536), and SVA were normalized in both groups. Preoperative and postoperative ODI, VAS, and SRS -22 scores were similar between groups. Complication rates between groups were similar as well (57.4% LLIF vs 57.7% ACR; p=0.98), including neurologic (16.8% vs 15.4%; p=0.859) and vascular (0% for both groups) injuries. CONCLUSIONS Use of ACR via lateral approach for correction of adult spinal deformity results in no increase in neurologic, vascular, or other overall complications rates, when compared to using LLIF alone, but is a more complex procedure and should be performed by highly experienced surgeons. Optimization of spino-pelvic parameters was achieved regardless of the technique employed. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

184. Comparison of stand-alone lateral lumbar interbody fusion and open laminectomy and posterolateral instrumented fusion in the treatment of adjacent segment disease following previous lumbar fusion surgery

BACKGROUND CONTEXT Recent studies have suggested that lateral lumbar interbody fusion (LLIF) can successfully treat adjacent segment disease (ASD), however, there are no studies to date that compare LLIF with the traditional open posterolateral fusion (PLF) in this cohort. PURPOSE Compare clinical and radiographic outcomes of patients who underwent stand-alone LLIF to those who underwent PLF for symptomatic ASD. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE Forty-seven consecutive patients who underwent a single- or two-level LLIF or open posterior decompression and PLF for symptomatic ASD between January 2007 and August 2016 after failure of conservative management. Exclusion criteria included: under the age of 18, follow-up of less than 24 months, presentation with adjacent level pathology that showed a spondylolisthesis greater than grade 1, active infection, active malignancy, or acute trauma. OUTCOME MEASURES Patient-reported outcomes (PRO) were collected on all patients preoperatively and postoperatively at intervals of 2 weeks, 6 weeks, 3 months, 1 year after surgery, and at the most recent postoperative visit using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS)–Back, and VAS–Leg surveys. Preoperative, immediate postoperative (day 1 or 2 after surgery) and most recent postoperative radiographs were assessed for: pelvic incidence, fusion, intervertebral disc height (average between anterior and posterior measurements of the distance between inferior end plate of the cephalad vertebral body and superior end plate of the caudal vertebral body), segmental and overall lordosis. METHODS Patients undergoing a single- or two-level LLIF or open posterior decompression and PLF for symptomatic ASD after failure of conservative management were included. Symptomatic ASD was diagnosed if back pain, neurogenic claudication, or lower extremity radiculopathy presented following a previous LF. Preoperative plain radiographs were evaluated for the presence of pathology associated with adjacent segment degeneration. RESULTS Forty-seven patients (23 LLIF, 24 PLF) met inclusion criteria. The LLIF group had significantly more male patients (p=0.028); however, there were no other differences in demographics between groups. Operative times (p CONCLUSIONS Stand-alone LLIF appears to be a safe and effective approach with substantially less perioperative morbidity, shorter length of hospitalization, acceptable complication rates, significantly better restoration of radiographic sagittal alignment parameters, and similar successful PRO compared to patients undergoing open PLF for symptomatic ASD. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Does Anterior Column Realignment Result in Greater Morbidity than Lateral Lumbar Interbody Fusion Alone When Treating Adult Spinal Deformity?

Abstract INTRODUCTION Anterior column realignment (ACR) can be utilized for correction of adult spinal deformity (ASD), but the additional benefit over lateral lumbar interbody fusion (LLIF) alone is unclear. METHODS Inclusion criteria were age = 18 yr, and one of the following: coronal cobb &gt; 20°, SVA &gt; 5 cm, PT &gt; 20°, PI-LL &gt; 10°. Patients were treated with circumferential MIS (cMIS) surgery or hybrid MIS surgery and had 1-year minimum follow-up. HRQOL (Oswestry Disability Index (ODI), visual analog score (VAS), SRS-22) and spinopelvic parameters were captured. RESULTS A total of 127 patients met inclusion criteria, 101 underwent LLIF and 26 had ACR. Average age and BMI were 66.3/27.7 and 67.8/27.4 (P = .654/0.957). The groups had similar rates of prior spine surgery (48.5% vs 57.7%; P = .403), cMIS (58.7% vs 73.1%; P = .222), posterior osteotomies (43.6% vs 34.6%; P = .409), levels instrumented (7.8 vs 8; P = .895), and interbody fusion levels (3.4 vs 3.6; P = .478). Preop (PT: 23.6/26.3; P = .373, SVA: 77.6/54.6 mm; P = .151, PI-LL: 17.3/20; P = .692) and postop spinopelvic parameters were similar between groups, except for postop SVA which was higher in the LLIF group (40 mm vs 13 mm; P = .028). 1 yr PI-LL (3.8 vs 5.8; P = .555), PT (20.6 vs 22.9; P = .536), and SVA were normalized in both groups. Preop and postop ODI, VAS, and SRS -22 scores were similar between groups. Complication rates between groups were similar as well (57.4% LLIF vs 57.7% ACR; P = .98), including neurologic (16.8% vs 15.4%; P = .859) and vascular (0% for both groups) injuries. CONCLUSION Use of ACR via lateral approach for correction of adult spinal deformity results in no increase in neurologic, vascular, or other overall complications rates, when compared to using LLIF alone. Optimization of spinopelvic parameters was achieved regardless of the technique employed. Segmental radiographic changes were not specifically evaluated, but regional and global parameters were not differentially impacted when comparing ACR and LLIF impact.

Revision for Endoscopic Diskectomy: Is Lateral Lumbar Interbody Fusion an Option?

This study aims to report the clinical outcome of stand-alone lateral lumbar interbody fusion (LLIF) on recurrent disk herniation and to compare the outcome of stand-alone LLIF to that of conventional transforaminal lumbar interbody fusion (TLIF). A retrospective study of 47 patients with recurrent disk herniation was included from January 2008 to October 2016. The inclusion criteria were 1) with recurrent disk herniation that needs revision surgery, 2) with only 1 previous percutaneous endoscopic lumbar diskectomy surgery, 3) underwent 1-level stand-alone LLIF or 1-level TLIF surgery, and 4) with follow-up more than 1 year. Patients were asked to complete the following questionnaires for outcome evaluation: visual analog scales (VAS) for both low back pain and leg pain, the Oswestry Disability Index (ODI), and the 12-item Short-Form Health Survey. Eighteen patients underwent stand-alone LLIF, and 29 patients underwent TLIF surgery. Radiographic analysis revealed a similar baseline and postoperative lumbar lordosis in both the LLIF and TLIF groups. Two weeks after surgery, the ODI and VAS scores showed a significant decrease in both groups. The TLIF group showed significantly larger postoperative VAS back pain after surgery (P= 0.03). For both VAS leg pain and ODI score during follow-up, no significance difference was found between the LLIF and TLIF groups. Stand-alone LLIF is a safe and effective approach with low morbidity and acceptable complication rates for patients with recurrent disk herniation after a previous percutaneous endoscopic lumbar diskectomy surgery. Compared with the TLIF procedure, LLIF could achieve a similar improvement of patient-reported outcome with a better VAS back pain score.

Changes in Sagittal Alignment Following Short-Level Lumbar Interbody Fusion: Comparison between Posterior and Lateral Lumbar Interbody Fusions.

Study DesignRetrospective case-control study.PurposeWe aimed to compare radiologic outcomes between posterior (PLIF) and lateral lumbar interbody fusion (LLIF) in short-level spinal fusion surgeries.Overview of LiteratureAlthough LLIF enables surgeons to insert large lordotic cages, it is unknown whether LLIF more effectively corrects local and global sagittal alignments compared with PLIF in short-level spinal fusion surgeries.MethodsRadiographic data acquired from patients with lumbar interbody fusion (≤3 levels) using PLIF or LLIF for degenerative lumbar diseases were analyzed. The following radiographic parameters were evaluated preoperatively and at 2 years postoperatively: segmental lordotic angle, disk height, lumbar lordosis (LL), pelvic tilt (PT), C7 sagittal vertical axis, and thoracic kyphosis (TK).ResultsIn total, 144 patients with PLIF (193 fused levels) and 101 with LLIF (159 fused levels) were included. Patients’ backgrounds and preoperative radiographic parameters for any level of fusion did not differ significantly between PLIF and LLIF procedures. The LLIF group exhibited significantly greater changes at 1-level fusion compared to the PLIF group in the parameters of segmental lordotic angle (5.1°±5.8° vs. 2.1°±5.0°, p<0.001), disk height (4.2±2.3 mm vs. 2.2±2.0 mm, p<0.001), LL (7.8°±7.6° vs. 3.9°±8.6°, p=0.004), and PI–LL (−6.9°±6.8° vs. −3.6°±10.1°, p=0.03). While, a similar trend was observed regarding 2-level fusion, significantly greater changes were only observed in LL (12.1°±11.1° vs. 4.2°±9.1°, p=0.047) and PI–LL (−11.2°±11.3° vs. −3.0°±9.3°, p=0.043), PT (−6.4°±4.9° vs. −2.5°±5.3°, p=0.049) and TK (7.8°±11.8° vs. −0.3°±9.7°, p=0.047) in the LLIF group at 3-level fusion.ConclusionsLLIF provides significantly better local sagittal alignment than PLIF in 1- or 2-level fusion cases and improves spinopelvic alignment and local alignment for 3-level fusion cases. Thus, LLIF was demonstrated to be a useful lumbar interbody fusion technique, constituting a powerful tool for achieving sagittal realignment with minimal surgical invasiveness.