Anterior Lumbar Interbody Fusion Group Research Articles

Comparison of Lumbosacral Fusion Grade in Patients after Transforaminal and Anterior Lumbar Interbody Fusion with Minimum 2-Year Follow-Up.

Generally, anterior lumbar interbody fusion (ALIF) was believed superior to transforaminal lumbar interbody fusion (TLIF) in induction of fusion. However, many studies have reported comparable results in lumbosacral fusion rate between the two approaches. This study aimed to evaluate the realistic lumbosacral arthrodesis rates following ALIF and TLIF in patients with degenerative spondylolisthesis as measured by CT and radiology. Ninety-six patients who underwent single-level L5-S1 fusion through ALIF (n = 48) or TLIF (n = 48) for degenerative spondylolisthesis at the Spine Center, University of California San Francisco, between October 2014 and December 2017 were retrospectively evaluated. Fusion was independently evaluated and categorized as solid fusion, indeterminate fusion, or pseudarthroses by two radiologists using the modified Brantigan-Steffee-Fraser (mBSF) grade. Clinical data on sex, age, body mass index, Meyerding grade, smoking status, follow-up times, complications, and radiological parameters including disc height, disc angle, segmental lordosis, and overall lumbar lordosis were collected. The fusion results and clinical and radiographic data were statistically compared between the ALIF and TLIF groups by using t-test or chi-square test. The mean follow-up period was 37.5 (ranging from 24 to 51) months. Clear, solid radiographic fusions were higher in the ALIF group compared with the TLIF group at the last follow-up (75% vs 47.9%, p = 0.006). Indeterminate fusion occurred in 20.8% (10/48) of ALIF cases and in 43.8% (21/48) of TLIF cases (p = 0.028). Radiographic pseudarthrosis was not significantly different between the TLIF and ALIF groups (16.7% vs 8.3%; p = 0.677). In subgroup analysis of the patients without bone morphogenetic protein (BMP), the solid radiographic fusion rate was significantly higher in the ALIF group than that in the TLIF group (78.6% vs 45.5%; p = 0.037). There were no differences in sex, age, body mass index, Meyerding grade, smoking status, or follow-up time between the two groups (p > 0.05). The ALIF group had more improvement in disc height (7.8 mm vs 4.7 mm), disc angle (5.2° vs 1.5°), segmental lordosis (7.0° vs 2.5°), and overall lumbar lordosis (4.7° vs 0.7°) compared with the TLIF group (p < 0.05). Overall complication rates were similar between the TLIF and ALIF groups (10.4% vs 8.33%; p > 0.999). With a minimum 2-year radiographic analysis of arthrodesis at lumbosacral level by radiologists, the rate of solid radiographic fusions was higher in the ALIF group compared with the TLIF group, whereas the TLIF group had a higher rate of indeterminate fusion. Radiographic pseudarthrosis did not differ significantly between the TLIF and ALIF groups.

Comparison of ALIF and PLIF in Isthmic Lumbosacral Spondylolisthesis. A Multicenter Surveillance Study of 602 cases from the German Spine Registry (DWG Register).

Isthmic spondylolisthesis most commonly occurs in the lumbosacral junction and can cause backpain and radicular pain as well as stiffness with progressive immobilization, with a negative impact on an individual's ability to work and quality of life. Multiple operative treatments are currently available. This study aims to compare complications, demography, and clinical features between anterior lumbar interbody fusion (ALIF) and posterior lumber body fusion (PLIF) in the operative treatment in isthmic spondylolisthesis. An analysis of data from the German spine registry (Deutsche Wirbelsäulengesellschaft [DWG]-Register) of patients who underwent operative treatment (PLIF and ALIF) for isthmic spondylolisthesis in the sacrolumbar junction in 170 departments between January 2017 and May 2021 was performed. Age, gender, American Society of Anesthesiologists (ASA) score, surgical approach, smoker/nonsmoker, as well as severeness of the spondylolisthesis according to the Meyerding classification were evaluated. In total, 602 patients undergoing fusion in L5/S1 were identified in the registry, n = 570 PLIF (group 1) and n = 32 ALIF (group 2). A significant difference in the ASA score between the two groups was noted; group 1 had more patients suffering a more debilitating disease in comparison to group 2. There was no significant difference in gender, grade of spondylolisthesis, age, or smoking status. Significant differences were found in operative and postoperative variables and complications (fusion material, dura injury). No difference was found between the two procedures in terms of symptomatic benefit of patients who underwent either ALIF or PLIF. According to the DWG Register, PLIF was the preferred method to treat isthmic spondylolisthesis in the sacrolumbar junction in Germany. To compare these two spine fusion techniques, further studies with an adequate sample size and follow-up period are required.

Comparison of radiographic and clinical outcomes between ALIF, OLIF, and TLIF over 2-year follow-up: a comparative study

BackgroundRegarding the increasing adoption of oblique lateral interbody fusion (OLIF) for treating degenerative lumbar disorders, we aimed to evaluate whether OLIF, one of the options for anterolateral approach lumbar interbody fusion, demonstrate clinical superiority over anterior lumbar interbody fusion (ALIF) or posterior approach, represented by transforaminal lumbar interbody fusion (TLIF).MethodsPatients who received ALIF, OLIF, and TLIF for symptomatic degenerative lumbar disorders during the period 2017–2019 were identified. Radiographic, perioperative, and clinical outcomes were recorded and compared during 2-year follow-up.ResultsA total of 348 patients with 501 correction levels were enrolled in the study. Fundamental sagittal alignment profiles were substantially improved at 2-year follow-up, particularly in the anterolateral approach (A/OLIF) group. The Oswestry disability index (ODI) and EuroQol-5 dimension (EQ-5D) in the ALIF group were superior when compared to the OLIF and TLIF group 2-year following surgery. However, comparisons of VAS-Total, VAS-Back, and VAS-Leg revealed no statistically significance across all approaches. TLIF demonstrated highest subsidence rate of 16%, while OLIF had least blood loss and was suitable for high body mass index patients.ConclusionsRegarding treatment for degenerative lumbar disorders, ALIF of anterolateral approach demonstrated superb alignment correction and clinical outcome. Comparing to TLIF, OLIF possessed advantage in reducing blood loss, restoring sagittal profiles and the accessibility at all lumbar level while simultaneously achieving comparable clinical improvement. Patient selection in accordance with baseline conditions, and surgeon preference both remain crucial issues circumventing surgical approach strategy.

Comparison of Outcomes of Multi-Level Anterior, Oblique, Transforaminal Lumbar Interbody Fusion Surgery : Impact on Global Sagittal Alignment.

To compare the outcomes of anterior lumbar interbody fusion (ALIF), oblique lumbar interbody fusion (OLIF), and transforaminal lumbar interbody fusion (TLIF) in terms of global sagittal alignment. From January 2007 to December 2019, 141 adult patients who underwent multilevel interbody fusion for lumbar degenerative disorders were enrolled. Regarding the approach, patients were divided into the ALIF (n=23), OLIF (n=60), and TLIF (n=58) groups. Outcomes, including local radiographic parameters and global sagittal alignment, were then compared between the treatment groups. Regarding local radiographic parameters, ALIF and OLIF were superior to TLIF in terms of the change in the anterior disc height (7.6±4.5 mm vs. 6.9±3.2 mm vs. 4.7±2.9 mm, p<0.001), disc angle (-10.0°±6.3° vs. -9.2°±5.2° vs. -5.1°±5.1°, p<0.001), and fused segment lordosis (-14.5°±11.3° vs. -13.8°±7.5° vs. -7.4°±9.1°, p<0.001). However, regarding global sagittal alignment, postoperative lumbar lordosis (-42.5°±9.6° vs. -44.4°±11.6° vs. -40.6°±12.3°, p=0.210), pelvic incidence-lumbar lordosis mismatch (7.9°±11.3° vs. 6.7°±11.6° vs. 11.5°±13.0°, p=0.089), and the sagittal vertical axis (24.3±28.5 mm vs. 24.5±34.0 mm vs. 25.2±36.6 mm, p=0.990) did not differ between the groups. Although the anterior approaches were superior in terms of local radiographic parameters, TLIF achieved adequate global sagittal alignment, comparable to the anterior approaches.

P118. Anterior versus lateral lumbar fusion: a comparison of 2-year outcomes in the treatment of degenerative spinal disorders

<h3>BACKGROUND CONTEXT</h3> Extreme lateral interbody fusion (XLIF) and anterior lumbar interbody fusion (ALIF) have both been progressively utilized by spinal surgeons, offering advantages of reduced tissue trauma, blood loss and improvements in postoperative patient reported outcomes. Although the literature has reported a higher proportion of neurological complications in XLIF, the anterior approach has been associated with a larger overall complication proportion, including a greater number of vascular and visceral complications. However, there is a paucity of reports comparing the two approaches over the long-term. Therefore, the purpose of this study was to assess and compare the overall revision rates, perioperative complications and functional clinical outcomes with minimum 2-year followup in both ALIF and XLIF. <h3>PURPOSE</h3> To compare ALIF versus XLIF in the treatment of degenerative spinal disorders with minimum 2-year followup. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort comparative study. <h3>PATIENT SAMPLE</h3> A total of 293 patients from 2013-2018 with a minimum follow-up of 2 years. One hundred and seventy-eight patients underwent ALIF and 115 patients underwent XLIF. <h3>OUTCOME MEASURES</h3> (1) Revision rate and average time to revision; (2) Perioperative complications; (3) Functional outcome scores including Oswestry Disability Index (ODI) and Visual Analog Scale for back (VAS-b). <h3>METHODS</h3> A retrospective review was performed to identify all patients between 2013-2018 who underwent ALIF or XLIF for degenerative lumbar spinal disorders with a minimum followup of 2 years. Demographic data was recorded and compared between both cohorts. Revision rates and time to revision in each group were compared. Perioperative complications were recorded. Functional outcomes were assessed with ODI and VAS back measurements at followup visits. Standard binomial and categorical comparative analyses were performed. <h3>RESULTS</h3> A total of 293 patients were included, 178 in the ALIF cohort and 115 in the XLIF cohort. Mean followup for the XLIF and ALIF groups were 46.3 and 42.2 months, respectively. The overall revision rate was 7.8% for the XLIF group and 7.9% for the ALIF group (p= 0.990). The average time to revision was 270.1 ± 133.0 days and 301.1 ± 140.7 days for the ALIF and XLIF groups, respectively (p= 0.058). The most common reason for revision in each cohort was persistent radiculopathy in the ALIF group (57.1%) and symptomatic adjacent segment disease in the XLIF group (44.4%). Three patients (1.7%) in the ALIF group required intraoperative repair of the common iliac vein due to incidental transection perioperatively whereas one patient (0.9%) underwent repair of the dura due to incidental durotomy in the XLIF cohort (p= 0.557). There were 46 males and 69 females in the XLIF cohort compared to 89 males and 89 females in the ALIF cohort (p= 0.094). Both cohorts experienced significant improvements in their functional outcomes scores compared to their preoperative values. VAS scores decreased by a mean of 5.6 in the XLIF group and a mean of 2.5 in the ALIF group, a significant difference (p= <0.001). <h3>CONCLUSIONS</h3> Our 2-year results show revision and overall complication rates did not differ significantly between XLIF and ALIF after 2-year followup. However, the ALIF group had a larger number of complications which were all related to vascular injury. Regarding patient reported outcomes, the XLIF cohort had significantly greater VAS-b score improvement compared to the ALIF cohort. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

A systematic review and meta-analysis of the clinical efficacy of anterior lumbar interbody fusion in the treatment of orthopedic spondylolisthesis.

Many studies have reported the advantages of anterior lumbar interbody fusion (ALIF), but the technique is associated with many complications involving nerve injury. This meta-analysis compared the outcome indicators associated with 2 fusion methods, namely, ALIF and posterolateral fusion (PLF). The clinical efficacy of ALIF was explored to provide evidence-based data for the determination of surgical methods for treating orthopedic spondylolisthesis. Relevant literatures were retrieved from the CBMdisc, CNKI, PubMed, EBSCO, MEDLINE, Science Direct, and Cochrane databases. Keywords in Chinese and English included spondylolisthesis, spine, surgical treatment, ALIF, and PLF. Data including the visual analogue scale (VAS) score, the Oswestry Disability Index (ODI), time of operation, and fusion rate were collated. According to Cochrane manual, Rev Man 5.3 software was used for analysis. A total of 6 articles were included in this meta-analysis. There were significant differences in intraoperative blood loss [Z=3.34; mean difference (MD) =-142.54; 95% confidence interval (CI): -226.17 to -58.92; P=0.0008] and operation time (Z=5.45; MD =-54.31; 95% CI: -73.83 to -34.79; P<0.00001) between patients in the ALIF group and patients in the PLF group. Significant differences were observed in VAS score (Z=3.55; MD =-1.04; 95% CI: -1.62 to -0.47; P=0.0004) nor ODI score (Z=3.07; MD =-6.33; 95% CI: -10.37 to -2.28; P=0.002) between the ALIF group and the PLF group. Interestingly, there was a significant difference in the hospitalization time between the 2 groups (Z=2.39; MD=-1.48; 95% CI: -2.70 to -0.27; P=0.02). Bone fusion rate was no significantly different between patients in the ALIF group and patients in the PLF group [Z=0.43; odds ratio (OR) =0.42; 95% CI: 0.01 to 21.82; P=0.66]. The results of this meta-analysis confirmed that ALIF can effectively improve the degree of spondylolisthesis, provide superior structural stability, and ensure surgical efficacy.

Anterior Lumbar Interbody Fusion (ALIF) or Transforaminal Lumbar Interbody Fusion (TLIF) for Fusion Surgery in L5/S1 - What Is the Best Way to Restore a physiological Alignment?

A retrospective single center cohort study with prospective collected data from an institutional spine registry. To determine whether restoration of lordosis L5/S1 is possible with both anterior lumbar interbody fusion (ALIF) and transforaminal lumbar interbody fusion (TLIF) and to find out which technique is superior to recreate lordosis in L5/S1. Seventy-seven patients with ALIF and seventy-nine with TLIF L5/S1 were included. Operation time, estimated blood loss), and complications were evaluated. Segmental lordosis L5/S1 and L4/5, overall lordosis, and proximal lordosis (L1 to L4) were measured in X-rays before and after surgery. Oswesery disability index and EQ-5D were assessed before surgery, and 3 and 12 months after surgery. Mean operation time was 176.9 minutes for ALIF and 195.7 minutes for TLIF (p = 0.048). Estimated blood loss was 249.2 cc for ALIF and 362.9 cc for TLIF (p = 0.005). In terms of complications, only a difference in dural tears were found (TLIF 6, ALIF none; p = 0.014). Lordosis L5/S1 increased in the ALIF group (15.8 to 24.6°; p < 0.001), whereas no difference was noted in the TLIF group (18.4 to 19.4°; p = 0.360). Clinical results showed significant improvement in the Oswesery disability index (ALIF: 43 to 21.9, TLIF: 45.2 to 23.0) and EQ-5D (ALIF: 0.494 to 0.732, TLIF: 0.393 to 0.764) after 12 months in both groups, without differences between the groups. ALIF and TLIF are comparable methods for performing fusion at L5/S1, with good clinical outcomes and comparable rates of complications. However, there is only a limited potential for recreating lordosis at L5/S1 with a TLIF.

Comparison of surgical outcomes between oblique lateral interbody fusion (OLIF) and anterior lumbar interbody fusion (ALIF)

ObjectiveAlthough oblique lateral interbody fusion (OLIF) utilizes the similar approach in anterior lumbar interbody fusion (ALIF), OLIF is essentially a lateral lumbar interbody fusion (LLIF). Therefore, OLIF may have advantages in LLIF that the lateral cage can achieve greater restoration of the disc height and angle. We aimed to compared the surgical outcomes between OLIF and ALIF. MethodsThis study involved 47 consecutive patients who underwent a single-level OLIF and 45 consecutive patients who underwent a single-level ALIF at L2-L5 levels. Radiological measurements included the changes of anterior/posterior disc height, coronal/sagittal disc angle, foramen cross-sectional area (CSA), cage position from the anterior margin of the lower vertebra, fusion rate, and cage subsidence using the serial radiographs and computed tomography preoperatively and at the postoperative 1-year follow-up. Clinical outcomes were assessed by visual analog scale (VAS) for back/leg pain, Oswestry disability index (ODI), and the occurrence of perioperative complications. ResultsThe baseline radiological and clinical parameters were similar between the OLIF and ALIF groups (all P > 0.05). At postoperative 1 year, the mean anterior disc height was higher in the OLIF group than the ALIF group (11.4 ± 1.9 mm vs. 9.6 ± 2.6 mm, P = 0.021). The mean sagittal disc angle was also greater in the OLIF group than the ALIF group (10.9 ± 4.4° vs. 8.9 ± 5.8°, P < 0.001). The mean cage position was 5.8 ± 2.1 mm in the OLIF group and 8.7 ± 2.3 mm in the ALIF group (P < 0.001). There was no difference in the postoperative changes of coronal disc angles, foramen CSA, fusion rate, cage subsidence, VAS for back/leg pain, ODI, and the occurrence of perioperative complications between the OLIF and ALIF groups (all P > 0.05). ConclusionsOLIF showed a greater increase in disc height and segmental lordosis than ALIF with comparable complications. OLIF is a meaningful progress from ALIF.

Functional and radiological outcome of anterior retroperitoneal versus posterior transforaminal interbody fusion in the management of single-level lumbar degenerative disease.

In this study the authors compared the anterior lumbar interbody fusion (ALIF) and posterior transforaminal lumbar interbody fusion (TLIF) techniques in a homogeneous group of patients affected by single-level L5-S1 degenerative disc disease (DDD) and postdiscectomy syndrome (PDS). The purpose of the study was to analyze perioperative, functional, and radiological data between the two techniques. A retrospective analysis of patient data was performed between 2015 and 2018. Patients were clustered into two homogeneous groups (group 1 = ALIF, group 2 = TLIF) according to surgical procedure. A statistical analysis of clinical perioperative and radiological findings was performed to compare the two groups. A senior musculoskeletal radiologist retrospectively revised all radiological images. Seventy-two patients were comparable in terms of demographic features and surgical diagnosis and included in the study, involving 32 (44.4%) male and 40 (55.6%) female patients with an average age of 47.7 years. The mean follow-up duration was 49.7 months. Thirty-six patients (50%) were clustered in group 1, including 31 (86%) with DDD and 5 (14%) with PDS. Thirty-six patients (50%) were clustered in group 2, including 28 (78%) with DDD and 8 (22%) with PDS. A significant reduction in surgical time (107.4 vs 181.1 minutes) and blood loss (188.9 vs 387.1 ml) in group 1 (p < 0.0001) was observed. No significant differences in complications and reoperation rates between the two groups (p = 0.561) was observed. A significant improvement in functional outcome was observed in both groups (p < 0.001), but no significant difference between the two groups was found at the last follow-up. In group 1, a faster median time of return to work (2.4 vs 3.2 months) was recorded. A significant improvement in L5-S1 postoperative lordosis restoration was registered in the ALIF group (9.0 vs 5.0, p = 0.023). According to these results, interbody fusion is effective in the surgical management of discogenic pain. Even if clinical benefits were achieved earlier in the ALIF group (better scores and faster return to work), both procedures improved functional outcomes at last follow-up. The ALIF group showed significant reduction of blood loss, shorter surgical time, and better segmental lordosis restoration when compared to the TLIF group. No significant differences in postoperative complications were observed between the groups. Based on these results, the ALIF technique enhances radiological outcome improvement in spinopelvic parameters when compared to TLIF in the management of adult patients with L5-S1 DDD.

P132. Is there a difference in clinical outcomes between single level and two level anterior lumbar interbody fusion for degenerative disc disease?

BACKGROUND CONTEXT Anterior lumbar interbody fusion (ALIF) has shown significant improvements in clinical outcomes for patients with degenerative disc disease causing lower back pain and foraminal stenosis. However, few studies have examined if there is a difference between outcomes in single level vs two level standalone ALIF. PURPOSE The purpose of this study was to assess for a difference in outcomes in single level vs two-level ALIF. STUDY DESIGN/SETTING Retrospective cohort study of patients treated at a single academic institution by a single surgeon. PATIENT SAMPLE Consecutive adult patients from 2011 to 2019 with the diagnosis of degenerative disc disease who underwent a single level (L5-S1) vs two level (L4-S1) standalone ALIF were included in this study. Only patients with 6 months of follow-up were analyzed. OUTCOME MEASURES Patient demographic data including age, body mass index, gender and American Society of Anesthesiologists classification was collected. Visual analog scale (VAS) pain scores for the back and leg, Oswestry Disability Index (ODI), Short Form 12 (SF-12) and Veterans RAND 12 (VR-12) scores were collected for clinical outcomes preoperatively and at the final postoperative visit. METHODS This study was a retrospective review of prospectively collected data. The patients were divided into cohorts of single level vs level ALIFs. Demographic data was compared between the two cohorts to look for baseline differences. Changes between preoperative and final clinical outcomes were compared using bivariate and multivariate linear regressions. Patients who achieved the minimal clinically important difference (MCID) in VAS and ODI scores from both groups were further analyzed with bivariate and multivariate linear regressions to assess for significant differences in outcomes. RESULTS A total of 73 patients were included. Fifty-six (76.7%) underwent a single level ALIF and 17 (23.3%) underwent two level ALIF. There were no baseline differences in patient demographics, nor in preoperative clinical scores. Both cohorts demonstrated improvements in all clinical outcomes postoperatively, and there was no significant difference between either group in bivariate and multivariate regression analysis of the postoperative clinical outcomes. Twenty patients (35.7%) in the single level ALIF cohort and seven patients (41.2%) in the two-level ALIF groups met the MCID cutoffs in VAS and ODI scores, and there was no significant difference between these patients in outcomes. CONCLUSIONS Both single-level L5-S1 and two-level L4-S1 standalone ALIF for degenerative disc disease demonstrate improvements in all clinical outcomes postoperatively. There is no significant difference between patients who underwent a single-level vs two-level stand-alone ALIF. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Anterior lumbar compared to oblique lumbar interbody approaches for multilevel fusions to the sacrum in adults with spinal deformity and degeneration.

In adult spinal deformity and degenerative conditions of the spine, interbody fusion to the sacrum often is performed to enhance arthrodesis, induce lordosis, and alleviate stenosis. Anterior lumbar interbody fusion (ALIF) has traditionally been performed, but minimally invasive oblique lumbar interbody fusion (OLIF) may or may not cause less morbidity because less retraction of the abdominal viscera is required. The authors evaluated whether there was a difference between the results of ALIF and OLIF in multilevel anterior or lateral interbody fusion to the sacrum. Patients from 2013 to 2018 who underwent multilevel ALIF or OLIF to the sacrum were retrospectively studied. Inclusion criteria were adult spinal deformity or degenerative pathology and multilevel ALIF or OLIF to the sacrum. Demographic, implant, perioperative, and radiographic variables were collected. Statistical calculations were performed for significant differences. Data from a total of 127 patients were analyzed (66 OLIF patients and 61 ALIF patients). The mean follow-up times were 27.21 (ALIF) and 24.11 (OLIF) months. The mean surgical time was 251.48 minutes for ALIF patients and 234.48 minutes for OLIF patients (p = 0.154). The mean hospital stay was 7.79 days for ALIF patients and 7.02 days for OLIF patients (p = 0.159). The mean time to being able to eat solid food was 4.03 days for ALIF patients and 1.30 days for OLIF patients (p < 0.001). After excluding patients who had undergone L5-S1 posterior column osteotomy, 54 ALIF patients and 41 OLIF patients were analyzed for L5-S1 radiographic changes. The mean cage height was 14.94 mm for ALIF patients and 13.56 mm for OLIF patients (p = 0.001), and the mean cage lordosis was 15.87° in the ALIF group and 16.81° in the OLIF group (p = 0.278). The mean increases in anterior disc height were 7.34 mm and 4.72 mm for the ALIF and OLIF groups, respectively (p = 0.001), and the mean increases in posterior disc height were 3.35 mm and 1.24 mm (p < 0.001), respectively. The mean change in L5-S1 lordosis was 4.33° for ALIF patients and 4.59° for OLIF patients (p = 0.829). Patients who underwent multilevel OLIF and ALIF to the sacrum had comparable operative times. OLIF was associated with a quicker ileus recovery and less blood loss. At L5-S1, ALIF allowed larger cages to be placed, resulting in a greater disc height change, but there was no significant difference in L5-S1 segmental lordosis.

P36. Interbody spacers placed via bilateral-TLIF provide higher vertebral endplate contact: a micro-CT analysis

BACKGROUND CONTEXT The transforaminal lumbar interbody fusion (TLIF) approach was developed to avoid the risks of the anterior lumbar interbody fusion (ALIF) and posterior lumbar interbody fusion (PLIF) approaches, and their potential for damage to the major vessels and the neurological elements, respectively. Contact between the entire spacer and the adjacent endplates of these various techniques is paramount to providing stability, increasing fusion rates, and reducing subsidence. A novel bilateral-TLIF technique includes reconstruction via a bilateral facetectomy and the placement of two interbody spacers along the lateral margins of the disc space. Bone graft is pre-packed in the graft chamber as well as between spacers. PURPOSE The goal of this study was to assess spacer and graft contact with the endplate of the proposed technique compared to various standard constructs. STUDY DESIGN/SETTING In vitrobiomechanics study. OUTCOME MEASURES Spacer and graft contact percentage was calculated from sagittal images across the entire width of the disc space for each specimen. METHODS Twenty-four fresh frozen cadaveric spines (L3–L4/L5–S1) were divided into four groups with equivalent bone mineral density average scores (n=6). Specimens were instrumented with either (1) one static ALIF spacer; (2) one standard TLIF static oblique spacer (Ob); (3) two static bilateral-TLIF spacers (BiSt); or (4) two expandable bilateral-TLIF spacers (BiEx). Specimens were scanned using the SkyScan-1173 (Bruker microCT, Belgium) with an isotropic resolution of 35um. Quantitative analysis was performed using DataViewer (Bruker microCT) and CTAn software (Bruker microCT). Based on sagittal images, spacer and graft contact percentage was calculated by dividing the contact length of graft and spacer on the endplate, by endplate length. The relative percentage was averaged across the entire width of the disc space for each specimen. Statistical analysis was performed (p RESULTS BiST (27.5%) exhibited the highest spacer and graft contact percentage followed by BiEX (21.4%) > ALIF (19.6%) > Ob (9.9%) (Figure 1). ALIF, BiST, and BiEX groups had significantly higher contact with the vertebral endplate compared to Ob (p=0.005, 0.000, and 0.001, respectively). CONCLUSIONS The proposed bilateral-TLIF technique resulted in relative spacer and graft contact area comparable to ALIF and significantly increased contact with the endplate compared to an oblique spacer. A benefit to the proposed approach is higher graft contact with the endplate due to graft packed between the spacers. It can be suggested that because of higher graft contact, this unique approach may potentially increase fusion rates. FDA DEVICE/DRUG STATUS Interbody spacers (Approved for this indication)

Fusion technique does not affect short-term patient-reported outcomes for lumbar degenerative disease

Background/ContextDegenerative lumbar disease can be addressed via an anterior or posterior approach, and with or without the use of an interbody cage. Although several studies have compared the type of approach and technique, there is a lack of literature assessing patient-reported outcome measures (PROMs) and radiographic parameters between different fusion techniques. PurposeTo determine whether the surgical approach and fusion technique for lumbar degenerative disease had an effect on short-term PROMs and radiographic parameters. Study Design/SettingRetrospective Cohort Study. Patient SampleThree hundred and ninety-one patients who underwent a 1–3 level lumbar spine fusion procedure at a high-volume academic center were retrospectively identified. Patients were divided into three groups based on the type of fusion they underwent: posterolateral fusion (PLF), anterior lumbar interbody fusion (ALIF), or transforaminal lumbar interbody fusion (TLIF). Outcome MeasuresPROMs: Short Form-12 (SF-12) Physical Component Score (PCS) and Mental Component Score (MCS), Oswestry Disability Index (ODI), Visual Analog Score (VAS) Back, VAS Leg. Spinopelvic measurements: Pelvic Tilt (PT), Sacral Slope (SS), Pelvic Incidence (PI), Lumbar Lordosis (LL), Segmental Lordosis (SL), PI–LL mismatch. MethodsPatients with less than 1-year follow-up were excluded from the cohort. Pre- and postoperative spinopelvic measurements were obtained for all patients. Univariate analysis (Chi-squared/Fisher's exact test or ANOVA test with post-hoc Bonferroni test) was used to compare among the three groups in the PROMs and radiographic spinopelvic parameters. Multiple linear regression was used to determine if fusion technique was an independent predictor of change in each patient outcome. ResultsTwo hundred and sixteen patients were included in the PLF group, 33 patients in the ALIF group, and 142 patients in the TLIF group. The PLF group was significantly older at baseline (p<.001) and had lower preoperative diagnosis rates of degenerative scoliosis and disc herniations (p<.001), whereas the ALIF group underwent a higher proportion of three-level fusions (p<.001). There was no significant difference in spinopelvic parameters preoperatively, however the ALIF group showed significantly more improvement in SL postoperatively (p=.004) than the PLF and TLIF groups. Within each group, SL improved for the PLF and ALIF groups (p=.002 for both), but not for the TLIF group (p=.238). Comparing patient outcomes, the ALIF group reported lower preoperative VAS Leg scores (p=.031), however, this difference resolved postoperatively. Stratifying for preoperative diagnosis, there were no significant differences in outcomes, except for a greater improvement in VAS Leg scores for degenerative scoliosis patients undergoing ALIF. Using multivariate analysis, fusion technique was not found to be a significant predictor of change in any patient outcome or in odds of revision. ConclusionsLumbar degenerative disease can be treated with several different fusion techniques, however, the relationship between type of fusion and PROMs is not established. Based on the findings in this study, the ALIF group showed greater improvement in SL compared with the PLF and TLIF groups, however, there was no difference noted in overall LL, PI–LL mismatch or other spinopelvic parameters. Despite these radiographic findings, patient outcome measures remained similar between all three fusion types.

Decreased estimated blood loss in lateral trans-psoas versus anterior approach to lumbar interbody fusion for degenerative spondylolisthesis

The goal of the current study was to compare the perioperative and post-operative outcomes of eXtreme lateral trans-psoas approach (XLIF) versus anterior lumbar interbody fusion (ALIF) for single level degenerative spondylolisthesis. The ideal approach for degenerative spondylolisthesis remains controversial. Consecutive patients undergoing single level XLIF (n=21) or ALIF (n=54) for L4-5 degenerative spondylolisthesis between 2008-2012 from a single academic center were retrospectively reviewed. Groups were compared for peri-operative data (estimated blood loss, operative time, adjunct procedures or additional implants), radiographic measurements (L1-S1 cobb angle, disc height, fusion grade, subsidence), 30-day complications (infection, DVT/PE, weakness/paresthesia, etc.), and patient reported outcomes (leg and back Numerical Rating Scale, and Oswestry Disability Index). Estimated blood loss was significantly lower for XLIF [median 100; interquartile range (IQR), 50-100 mL] than for ALIF (median 250; IQR, 150-400 mL; P<0.001), including after adjusting for significantly higher rates of posterior decompression in the ALIF group. There were no significant differences in rates of complications within 30 days, radiographic outcomes, or in re-operation rates. Both groups experienced significant pain relief post-operatively. The lateral trans-psoas approach is associated with diminished blood loss compared to the anterior approach in the treatment of degenerative spondylolisthesis. We were unable to detect differences in radiographic outcomes, complication rates, or patient reported outcomes. Continued efforts to directly compare approaches for specific indications will minimize complications and improve outcomes. Further studies will continue to define indications for lateral versus anterior approach to lumbar spine for degenerative spondylolisthesis.

Benefits of Enhanced Recovery After Surgery for fusion in degenerative spine surgery: impact on outcome, length of stay, and patient satisfaction.

OBJECTIVEEnhanced Recovery After Surgery (ERAS) proposes a multimodal, evidence-based approach to perioperative care. Thanks to the improvement in care protocols and the fluidity of the patient pathway, the first goal of ERAS is the improvement of surgical outcomes and patient experience, with a final impact on a reduction in the hospital length of stay (LOS). The implementation of ERAS in spinal surgery is in the early stages. The authors report on their initial experience in applying an ERAS program to several degenerative spinal fusion procedures.METHODSThe authors selected two 2-year periods: the first from before any implementation of ERAS principles (pre-ERAS years 2012-2013) and the second corresponding to a period when the paradigm was applied widely (post-ERAS years 2016-2017). Patient groups in these periods were retrospectively compared according to three degenerative conditions requiring fusion: anterior cervical discectomy and fusion (ACDF), anterior lumbar interbody fusion (ALIF), and posterior lumbar fusion. Data were collected on patient demographics, operative and perioperative data, LOSs, 90-day readmissions, and morbidity. ERAS-trained nurses were involved to support patients at each pre-, intra-, and postoperative step with the help of a mobile application (app). A satisfaction survey was included in the app.RESULTSThe pre-ERAS group included 1563 patients (159 ALIF, 749 ACDF, and 655 posterior fusion), and the post-ERAS group included 1920 patients (202 ALIF, 612 ACDF, and 1106 posterior fusion). The mean LOS was significantly shorter in the post-ERAS group than in the pre-ERAS group for all three conditions. It was reduced from 6.06 ± 1.1 to 3.33 ± 0.8 days for the ALIF group (p < 0.001), from 3.08 ± 0.9 to 1.3 ± 0.7 days for the ACDF group (p < 0.001), and from 6.7 ± 4.8 to 4.8 ± 2.3 days for posterior fusion cases (p < 0.001). There was no significant difference in overall complications between the two periods for the ALIF (11.9% pre-ERAS vs 11.4% post-ERAS, p = 0.86) and ACDF (6.0% vs 8.2%, p = 0.12) cases, but they decreased significantly for lumbar fusions (14.8% vs 10.9%, p = 0.02). Regarding satisfaction with overall care among 808 available responses, 699 patients (86.5%) were satisfied or very satisfied, and regarding appreciation of the mobile e-health app in the perceived optimization of care management, 665 patients (82.3%) were satisfied or very satisfied.CONCLUSIONSThe introduction of the ERAS approach at the authors' institution for spinal fusion for three studied conditions resulted in a significant decrease in LOS without causing increased postoperative complications. Patient satisfaction with overall management, upstream organization of hospitalization, and the use of e-health was high. According to the study results, which are consistent with those in other studies, the whole concept of ERAS (primarily reducing complications and pain, and then reducing LOS) seems applicable to spinal surgery.

Iliac screws may not be necessary in long-segment constructs with L5–S1 anterior lumbar interbody fusion: cadaveric study of stability and instrumentation strain

BACKGROUND CONTEXTLumbosacral pseudoarthrosis and instrumentation failure is common with long-segment constructs. Optimizing lumbosacral construct biomechanics may help to reduce failure rates. The influence of iliac screws and interbody type on range of motion (ROM), rod strain (RS), sacral screw strain (SS) is not well-established. PURPOSEInvestigate the effects of transforaminal lumbar interbody fusion (TLIF), anterior lumbar interbody fusion (ALIF), and iliac screws on long-segment lumbosacral construct biomechanics. STUDY DESIGNBiomechanical study. PATIENT SAMPLEFourteen human cadaveric spine specimens. OUTCOME MEASURESLumbosacral ROM, RS, and SS. METHODSSpecimens were potted at L1 and the ilium. Specimens were equally divided into either an L5–S1 ALIF or TLIF group and underwent testing in the following conditions: (1) intact (2) L2–S1 pedicle screw rod fixation (PSR-S) (3) L2-ilium (PSR-I) (4) PSR-S+ALIF (ALIF-S) or TLIF (TLIF-S) (5) PSR-I + ALIF (ALIF-I) or TLIF (TLIF-I). Pure moment bending (7.5 Nm) in flexion, extension, lateral bending, axial rotation, and compressive loads (400N) were applied and ROM, SS, and RS were measured. Comparisons were performed using a one-way ANOVA (p<.05). RESULTSALIF-S and TLIF-S provided similar decreases in ROM as TLIF-I (p>.05). Compared to PSR-S, PSR-I significantly decreased SS during bending in all directions (p<.02) but increased RS in flexion and extension (p≤.02). Anterior lumbar interbody fusion-S provided similar decreases in SS as TLIF-I in all directions (p>.40) but had significantly less RS than TLIF-I in flexion, extension, compression (p<.01). TLIF-S had more SS than TLIF-I in flexion, extension, axial rotation (p<.02), while TLIF-S had less RS only in flexion (p=.03). Compared to PSR-I, ALIF-I decreased the RS (p<.02) but TLIF-I did not (p>.67). CONCLUSIONSIliac screws were protective of SS but increased RS at the lumbosacral junction. Constructs with ALIF and no iliac screws result in comparable SS as constructs with TLIF and iliac screws with significantly reduced RS. If iliac screws are utilized, ALIF but not TLIF reduces the iliac screw-induced RS. CLINICAL SIGNIFICANCEThere is a relatively high incidence of lumbosacral instrumentation failure in adult spinal deformity. Optimizing lumbosacral construct biomechanics may help to reduce failure rates. Iliac screws induce lumbosacral rod strain and may be responsible for instrumentation failure. Constructs with lumbosacral ALIF reduce iliac-screw induced rod strain and may obviate the need for fixation to the ilium.

Clinical and Radiologic Fate of the Lumbosacral Junction After Anterior Lumbar Interbody Fusion Versus Axial Lumbar Interbody Fusion at the Bottom of a Long Construct in CMIS Treatment of Adult Spinal Deformity.

Introduction:Surgeons use numerous arthrodesis strategies for fusion of the lumbosacral junction including anterior lumbar interbody fusion (ALIF) and axial lumbar interbody fusion (AxiaLIF). The optimal L5-S1 fusion strategy remains inconclusive. The purpose of this study is to compare the fate of the lumbosacral junction in ALIF versus AxiaLIF patients in terms of clinical and radiographic outcomes.Methods:Adult spinal deformity patients, treated with CMIS techniques, with at least 2-year follow-up who underwent AxiaLIF or ALIF at the lumbosacral junction were included. Patients were separated into two groups: AxiaLIF (56 patients) and ALIF (38 patients). Outcome measures included segmental lordosis, sagittal vertical alignment, lumbar lordosis (LL), pelvic incidence–LL mismatch, and pseudarthrosis, major complication, and revision surgery rates.Results:The ALIF group achieved greater postoperative and delta segmental lordosis, higher delta sagittal vertical alignment, higher delta LL, and lower postoperative pelvic incidence–LL mismatch. The pseudarthrosis, major complication, and revision surgery rates were higher in the AxiaLIF group. Five cases of pseudarthrosis at L5-S1 were seen, all in the AxiaLIF group.Discussion and Conclusion:ALIF patients showed more favorable radiographic correction parameters and lower rates of pseudarthrosis, major complications, and revision surgeries. ALIF is the preferred strategy for L5-S1 arthrodesis at a bottom of a long construct.

Comparative study of three surgical procedures of lumbar interbody fusion for adult low-grade isthmic spondylolisthesis

Objective To compare the clinical and radiographic outcomes of 3 kinds of lumbar interbody fusion (ALIF, PLIF, TLIF) for adult low-grade isthmic spondylolisthesis at L4, 5 and L5S1 levels. Methods Data of seventy patients with low-grade isthmic spondylolisthesis who had undergone different lumbar interbody fusion (LIF) procedures according to the assessment of the clinical manifestation, neurological symptoms, plane of the common iliac vessels and the width of vascular window by three-dimensional computed tomography angiography between May 2004 and May 2014 were retrospectively reviewed. 21 patients had undergone anterior LIF (ALIF)(13 males and 8 females with an average of 43.29±8.15 years old (range, 29-53 years old); L4,5 in ten, L5S1 in 11; Meyerding grade I 10 cases, grade II 11 cases); 25 patients had undergone posterior LIF (PLIF) (12 males and 13 females, with an average of 44.04±12.71 years old (range, 25-64 years old); L4, 5 in 12, L5S1 in 13; Meyerding grade I 15 cases, grade II 10 cases) and 24 patients had undergone transforaminal LIF (TLIF) (12 males and 12 females with an average of 45.00± 9.36 years old (range, 34-62 years old); L4, 5 in 12, L5S1 in 12; Meyerding grade I 11 cases, grade II 13 cases). Results All patients were followed up for 24-37 months (average, 25.6 ± 8.7 months). The visual analogue scale (VAS) in all groups were decreased from 7.05±0.87 (ALIF), 6.60±1.39 (PLIF), 6.75±1.11 (TLIF) pre-operation to 0.90±0.70, 0.96±0.68, 1.04±0.62 24 months after operation. Oswestry disability index (ODI) scores were decreased from 78.53%±6.25%, 79.80%±6.55%, 79.92%±8.10% pre-operation to 17.14%±3.01%, 21.32%±4.40%, 22.46%±3.87%. Perioperative data including operation time, blood loss, postoperative blood drainage, length of stay showed no significant difference between ALIF group and TLIF group, but showing significant difference comparing with PLIF group. The imageological results showed that ALIF procedure increased whole lumbar lordosis (WL) and disc height (DH), showing no significant difference comparing with PLIF group, but showing significant difference comparing with TLIF group. The ALIF procedure increased segmental lordosis angle (SL), showing significant difference comparing with PLIF group and TLIF group. The PLIF procedure decreased spondylolisthesis index (SI), showing significant difference comparing with A/TLIF group, but showing no significant difference between ALIF group and TLIF group. There was no significant difference showed comparing the L1 axis S1 distance (LASD) and sacral slope (SS), in three groups. The graft fusion was achieved in all patients after 6-8 months postoperatively without instrument failure or displacement. Conclusion Three surgical procedures of lumbar interbody fusion for adult low-grade isthmic spondylolisthesis showed silimar clinical efficacy. The ALIF procedure is superior in its capacity to restore WL, DH, and SL, and the P/TLIF procedure are superior in correcting the vertebral slippage and spinal cord decompression. Key words: Spinal fusion; Lumbar vertebrae; Spondylolysis; Surgical procedures, operative

Choice of Approach Does Not Affect Clinical and Radiologic Outcomes: A Comparative Cohort of Patients Having Anterior Lumbar Interbody Fusion and Patients Having Lateral Lumbar Interbody Fusion at 24 Months.

Study Design Retrospective analysis of prospectively collected registry data.Objective This study aimed to compare the clinical and radiologic outcomes between comparative cohorts of patients having anterior lumbar interbody fusion (ALIF) and patients having lateral lumbar interbody fusion (LLIF).Methods Ninety consecutive patients were treated by a single surgeon with either ALIF (n = 50) or LLIF (n = 40). Inclusion criteria were patients age 45 to 70 years with degenerative disk disease or grade 1 to 2 spondylolisthesis and single-level pathology from L1 to S1. Patient-reported outcome measures included pain (visual analog scale), disability (Oswestry Disability Index [ODI]), and quality of life (Short Form 36 physical component score [PCS] and mental component scores [MCS]). Assessment of fusion and measurement of lordosis and posterior disk height were performed on computed tomography scans.Results At 24 months, patients having ALIF had significant improvements in back (64%) and leg (65%) pain and ODI (60%), PCS (44%), and MCS (26%; p < 0.05) scores. Patients having LLIF had significant improvements in back (56%) and leg (57%) pain and ODI (52%), PCS (48%), and MCS (12%; p < 0.05) scores. Fourteen complications occurred in the ALIF group, and in the LLIF group, there were 17 complications (p > 0.05). The fusion rate was 100% for ALIF and 95% for LLIF (p = 0.1948). ALIF added ∼6 degrees of lordosis and 3 mm of height, primarily measured at L5–S1, and LLIF added ∼3 degrees of lordosis and 2 mm of height between L1 to L5. Mean follow-up was 34.1 months.Conclusions In comparative cohorts of patients having ALIF and patients having LLIF at 24 months postoperatively, there were no significant differences in clinical outcomes, complication rates, or fusion rates.

Postoperative posterior lumbar muscle changes and their relationship to segmental motion preservation or restriction: a randomized prospective study.

To date, it remains unclear whether the preservation of segmental motion by total disc replacement (TDR) or motion restriction by stand-alone anterior lumbar interbody fusion (ALIF) have an influence on postoperative degeneration of the posterior paraspinal muscles or the associated clinical results. Therefore, the purpose of the present prospective randomized study was to evaluate the clinical parameters and 3D quantitative radiological changes in the paraspinal muscles of the lumbar spine in surgically treated segments and superior adjacent segments after ALIF and TDR. A total of 50 patients with chronic low-back pain caused by single-level intervertebral disc degeneration (Pfirrmann Grade ≥ III) and/or osteochondrosis (Modic Type ≤ 2) without symptomatic facet joint degeneration (Fujiwara Grade ≤ 2, infiltration test) of the segments L4-5 or L5-S1 were randomly assigned to 2 treatment groups. Twenty-five patients were treated with a stand-alone ALIF and the remaining 25 patients underwent TDR. For ALIF and TDR, a retroperitoneal approach was used. At 1 week and at 12 months after surgery, CT was used to analyze paraspinal lumbar muscle tissue volume and relative fat content. Residual muscle tissue volume at 12 months and change in the relative fat content were compared between the groups. In addition, clinical parameters (visual analog scale [VAS] for low-back pain and Oswestry Disability Index [ODI] Questionnaire Version 2 for function) were compared. Compared with 1 week after surgery, the radiological analysis at 12 months revealed a small decrease in the posterior muscle volume (the mean decrease was < 2.5%), along with a small increase in the relative fat content (the mean increase was < 1.9%), in both groups at the index and superior adjacent segments. At the adjacent segment, the ALIF group presented significantly less muscle tissue volume atrophy and a smaller increase in fat content compared with the TDR group. At final follow-up, the clinical parameters related to pain and function were significantly improved in both groups compared with 1 week postsurgery, but there were no differences between the groups. Motion restriction via stand-alone ALIF and motion preservation via TDR both present small changes in the posterior lumbar paraspinal muscles with regard to volume atrophy or fatty degeneration at the index and superior adjacent segments. Therefore, although the clinical outcome was not affected by the observed muscular changes, the authors concluded that the expected negative influence of motion restriction on the posterior muscles compared with motion preservation does not occur on a clinically relevant level.