BACKGROUND: Interbody devices in anterior lumbar interbody fusion (ALIF) are currently a focus of innovation due to their potential to improve clinical outcomes. The purpose of the present study was to analyze complications and changes in spinopelvic parameters after ALIF with the novel Medacta MectaLIF interbody fusion device.
METHODS: Patients aged 18 to 80 years who underwent multilevel ALIF using this novel implant were identified. Demographic and surgical data were collected. Patients were divided into short- and long-fusion cohorts. A comparison of outcomes between the short- and long-fusion groups was performed using the Student t test for continuous variables and Fisher\'s exact test and the χ2 test for categorical variables. Analysis of the pre- vs postoperative radiographic data for the entire cohort was performed using the 2-tailed Student t test.
RESULTS: One hundred and eight patients met the inclusion criteria. No significant postoperative change was observed in L1-4 lumbar lordosis (LL). L1-S1 LL increased to a mean of 55.1 ± 12.8 (a mean change of 10.7 ± 14.5), and L4-S1 LL increased to a mean of 38.4 ± 8.7 (a mean increase of 7.5 ± 8.2), with pelvic incidence LL mismatch changing from 8.9 ± 15.1 to 1.1 ± 13.5 (n = 102). Related changes in sacral slope and pelvic tilt were also observed (33.0 ± 11.0 to 37.6 ± 10.9 and 19.6 ± 9.5 to 18.2 ± 9.1 [n = 103], respectively). Five patients (4.6%) experienced implant subsidence, 1 (0.9%) had implant migration, and 6 (5.6%) experienced a nonunion. There was no difference in the rates of complications associated with the novel implant in the short- and long-fusion cohorts.
CONCLUSIONS: This novel implant achieves correction of spinopelvic parameters with minimal complications. The ability to modify the implant intraoperatively based on the patient\'s anatomy can help achieve maximal contact area and therefore help reduce the risk of subsidence.
CONCLUSIONS: This modular implant can achieve correction of spinopelvic parameters with minimal medical and surgical complications.
METHODS:

OBJECTIVE: To determine of the impact of ALIF with minimally invasive unilateral pedicle screw fixation (UPSF) versus bilateral pedicle screw fixation (BPSF) on perioperative outcomes, radiographic outcomes, and the rates of fusion, subsidence, and adjacent segment stenosis.
METHODS: All adult patients who underwent one-level ALIF with UPSF or BPSF at an academic institution between 2015 and 2022 were retrospectively identified. Postoperative outcomes including length of hospital stay (LOS), wound complications, readmissions, and revisions were determined. The rates of fusion, screw loosening, adjacent segment stenosis, and subsidence were assessed on one-year postoperative CT. Lumbar alignment including lumbar lordosis, L4-S1 lordosis, regional lordosis, pelvic tilt, pelvic incidence, and sacral slope were assessed on standing x-rays at preoperative, immediate postoperative, and final postoperative follow-up. Univariate and multivariate analysis compared outcomes across posterior fixation groups.
RESULTS: A total of 60 patients were included (27 UPSF, 33 BPSF). Patients with UPSF were significantly younger (p = 0.011). Operative time was significantly greater in the BPSF group in univariate (p < 0.001) and multivariate analysis (ß=104.1, p < 0.001). Intraoperative blood loss, LOS, lordosis, pelvic parameters, fusion rate, subsidence, screw loosening, adjacent segment stenosis, and revision rate did not differ significantly between fixation groups. Though sacral slope (p = 0.037) was significantly greater in the BPSF group, fixation type was not a significant predictor on regression.
CONCLUSIONS: ALIF with UPSF relative to BPSF predicted decreased operative time but was not a significant predictor of postoperative outcomes. ALIF with UPSF can be considered to increase operative efficiency without compromising construct stability.

Background: Anterior lumbar interbody fusion (ALIF) and posterior spinal fusion (PSF) play pivotal roles in restoring lumbar lordosis in spinal surgery. There is an ongoing debate between combined single-position surgery and traditional prone-position PSF for optimizing segmental lumbar lordosis. Methods: This retrospective study analyzed 59 patients who underwent ALIF in the supine position followed by PSF in the prone position at a single institution. Cobb angles were measured preoperatively, post-ALIF, and post-PSF using X-ray imaging. One-way repeated measures ANOVA and post-hoc analyses with Bonferroni adjustment were employed to compare mean Cobb angles at different time points. Cohen\'s d effect sizes were calculated to assess the magnitude of changes. Sample size calculations were performed to ensure statistical power. Results: The mean segmental Cobb angle significantly increased from preoperative (32.2 ± 13.8 degrees) to post-ALIF (42.2 ± 14.3 degrees, Cohen\'s d: -0.71, p < 0.0001) and post-PSF (43.6 ± 14.6 degrees, Cohen\'s d: -0.80, p < 0.0001). There was no significant difference between Cobb angles after ALIF and after PSF (Cohen\'s d: -0.10, p = 0.14). The findings remained consistent when Cobb angles were analyzed separately for single-screw and double-screw ALIF constructs. Conclusions: Both supine ALIF and prone PSF significantly increased segmental lumbar lordosis compared to preoperative measurements. The negligible difference between post-ALIF and post-PSF lordosis suggests that supine ALIF followed by prone PSF can be an effective approach, providing flexibility in surgical positioning without compromising lordosis improvement.

UNASSIGNED: In anterior lumbar interbody fusion (ALIF), the use of integrated screws is attractive to surgeons because of the ease of implantation and no additional profile. However, the number and length of screws necessary for safe and stable implantation in various bone densities is not yet fully understood. The current study aims to determine how important both length and number of screws are for stability of ALIFs.
UNASSIGNED: Three bone models with densities of 10, 15, and 20 pounds per cubic foot (PCF) were chosen as surrogates. These were instrumented using the Z-Link lumbar interbody system with either 2, 3, or 4 integrated 4.5 × 20 mm screws or 4.5 × 25 mm screws (Zavation, LLC, Flowood, MS). The bone surrogates were tested with loading conditions resulting in spine extension to measure construct stiffness and peak force.
UNASSIGNED: The failure load of the construct was influenced by the length of screws (p=.01) and density of the bone surrogate (p<.01). There was no difference in failure load between using 2 screws and 3 screws (p=.32) or when using four 20 mm screws versus three 25 mm screws (p=.295).
UNASSIGNED: In our study, both bone density and length of screws significantly affected the construct\'s load to failure. In certain cases where a greater number of screws are unable to be implanted, the same stability can potentially be conferred with use of longer screws. Future clinical studies should be performed to test these biomechanical results.

BACKGROUND: Anterior lumbar interbody fusion (ALIF) can treat spondylolisthesis, degenerative disc disease and pseudoarthrosis. This approach facilitates complete discectomy, disc space distraction, indirect decompression of neural foramina and placement of large interbody devices. Several intra- and postoperative complications can be attributed to the anterior approach: vascular/visceral injury, hypogastric plexus injury and urogenital consequences. Spine-specific complications include implant migration, graft failure, pseudoarthrosis and persistent symptomology.
METHODS: This retrospective study reviewed patient demographics, medium-term outcomes and complication rates following ALIF surgery performed over a 5-year period. A total of 110 consecutive patients had undergone ALIF surgery at a single tertiary spinal centre. The database was reviewed with a primary outcome of identifying postoperative 90-day complications and whether a revision anterior operation was required after primary ALIF.
RESULTS: No patients required revision anterior operation after their primary ALIF surgery by final follow-up. Out of 110 patients, 11 (10%) recorded a complication attributed to the anterior stage of their operation within 90 days.
CONCLUSIONS: Our 90-day complication rate of 10% lies within the 2.6% acute complication and 40% overall complications rates described in previous literature. The risk of vascular/visceral injury is significant (3%) and we recommend that ALIF be performed as a dual surgeon procedure with a vascular-trained access surgeon accompanying the spinal surgeon. ALIF is a valid revision surgical option for failed posterior approaches leading to complications such as pseudoarthrosis. In our sample, 89% of patients were managed with posterior fixation to augment the anterior fusion as, biomechanically, this is a proven construct.

BACKGROUND: Adult spinal deformity (ASD) occurs from progressive anterior column collapse due to disc space desiccation, compression fractures, and autofusion across disc spaces. Anterior column realignment (ACR) is increasingly recognized as a powerful tool to address ASD by progressively lengthening the anterior column through the release of the anterior longitudinal ligament during lateral interbody approaches. Here, we describe the application of minimally invasive ACR through an oblique antepsoas corridor for deformity correction in a patient with adult degenerative scoliosis and significant sagittal imbalance.
METHODS: A 65-year-old female with a prior history of L4-5 transforaminal lumbar interbody fusion and morbid obesity presented with refractory, severe low-back and lower-extremity pain. Preoperative radiographs showed significant sagittal imbalance. Computed tomography showed a healed L4-5 fusion and a vacuum disc at L3-4 and L5-S1, whereas magnetic resonance imaging was notable for central canal stenosis at L3-4. The patient was treated with a first-stage L5-S1 lateral anterior lumbar interbody fusion with oblique L2-4 ACR. The second-stage posterior approach consisted of a robot-guided minimally invasive T10-ilium posterior instrumented fusion with a mini-open L2-4 posterior column osteotomy (PCO). Postoperative radiographs showed the restoration of her sagittal balance. There were no complications.
CONCLUSIONS: Oblique ACR is a powerful minimally invasive tool for sagittal plane correction. When combined with a mini-open PCO, substantial segmental lordosis can be achieved while eliminating the need for multilevel PCO or invasive three-column osteotomies.

OBJECTIVE: Biomechanical factors in lumbar fusions accelerate the development of adjacent-segment disease (ASD). Stiffness in the fused segment increases motion in the adjacent levels, resulting in ASD. The objective of this study was to determine if there are differences in the reoperation rates for symptomatic ASD (operative ASD) between anterior lumbar interbody fusion plus pedicle screws (ALIF+PS), posterior lumbar interbody fusion plus pedicle screws (PLIF+PS), transforaminal lumbar interbody fusion plus pedicle screws (TLIF+PS), and lateral lumbar interbody fusion plus pedicle screws (LLIF+PS).
METHODS: A retrospective study using data from the Kaiser Permanente Spine Registry identified an adult cohort (≥ 18 years old) with degenerative disc disease who underwent primary lumbar interbody fusions with pedicle screws between L3 to S1. Demographic and operative data were obtained from the registry, and chart review was used to document operative ASD. Patients were followed until operative ASD, membership termination, the end of study (March 31, 2022), or death. Operative ASD was analyzed using Cox proportional hazards models.
RESULTS: The final study population included 5291 patients with a mean ± SD age of 60.1 ± 12.1 years and a follow-up of 6.3 ± 3.8 years. There was a total of 443 operative ASD cases, with an overall incidence rate of reoperation for ASD of 8.37% (95% CI 7.6-9.2). The crude incidence of operative ASD at 5 years was the lowest in the ALIF+PS cohort (7.7%, 95% CI 6.3-9.4). In the adjusted models, the authors failed to detect a statistical difference in operative ASD between ALIF+PS (reference) versus PLIF+PS (HR 1.06 [0.79-1.44], p = 0.69) versus TLIF+PS (HR 1.03 [0.81-1.31], p = 0.83) versus LLIF+PS (HR 1.38 [0.77-2.46], p = 0.28).
CONCLUSIONS: In a large cohort of over 5000 patients with an average follow-up of > 6 years, the authors found no differences in the reoperation rates for symptomatic ASD (operative ASD) between ALIF+PS and PLIF+PS, TLIF+PS, or LLIF+PS.

We assessed the frequency of intraoperative complication rates related to access surgery, operating time, and intraoperative bleeding rates described in the literature for patients undergoing anterior lumbar interbody fusion (ALIF) to evaluate the adverse effects and, thus, help in therapeutic decision making and contribute to future clinical trials.
A systematic review was conducted of MEDLINE and Embase databases in March 2023. The main inclusion criteria were adult patients aged >18 years, with no maximum age limit; the use of ALIF; the presence of quantitative data on intraoperative complications; and randomized controlled trials and cohort studies. Vascular and peritoneal injuries were considered primary endpoints. The operative time and intraoperative bleeding rate were secondary endpoints. Reports and case series, case-control series, systematic reviews, and meta-analyses were excluded.
Eight studies were included with a total of 2395 patients. We found important quantitative data for future randomized clinical studies involving ALIF surgery, including the rate of vascular lesions (2.79%) and peritoneal lesions (0.37%). In addition to these factors, only 4 of the 8 studies addressed the average surgery time, with a total average of 145.61 minutes. Furthermore, 6 of the 8 articles reported the mean rate of intraoperative bleeding, with a total mean blood loss of 272.75 mL.
ALIF is a lumbar spine access technique with low intraoperative complications. Patients with contraindications have a higher risk of complications. Randomized clinical trials are needed to assess the efficacy and safety of the procedure.

UNASSIGNED: ALIF (anterior lumbar interbody fusion) and other spinal fusion surgeries are among the most common orthopaedic procedures requiring blood transfusions. However, blood transfusions have been associated with various complications, including adverse reactions and infections. The present study aims to identify independent risk factors for blood transfusions in patients undergoing single-level ALIF specifically to better identify high risk patients and optimize perioperative management.
UNASSIGNED: All patients who had undergone single-level ALIF patients for the treatment of degenerative spinal conditions, excluding traumatic, pathologic, and infectious etiologies, were identified by querying a multi-institutional surgical registry from 2005 to 2018. Multi-level fusions, PLIF/TLIF, and posterior procedures were also excluded. Mann-Whitney-U-Tests were used to analyze continuous variables, while Fisher\'s-Exact-Tests/Bonferroni-Corrected-Tests were used for categorical variables. Multivariate logistic regression analysis with alternating backward stepwise elimination and forward entry was implemented to identify significant predictors for blood transfusions within 72 hours after incision. The predicted probabilities were used in post-regression diagnostics to generate a Receiver Operating Characteristic (ROC) curve to assess model performance.
UNASSIGNED: 4,792 single-level ALIF patients met inclusion criteria - 183 (3.82%) had received blood transfusions within 72 hours after incision and 4,609 (96.18%) had not. Age ≥60 years (OR 1.954, p<0.001), preoperative transfusions (OR 33.758, p=0.023), extended operative times (≥197.0 minutes; 75th percentile) (OR 4.645, p<0.001), ASA≥3 (OR 1.395, p<0.001) and preoperative hematocrit levels (Hct) 30.00-37.99 (OR 1.562, p=0.016) and Hct <30.00 (OR 6.334, p<0.001) were shown to be significant independent risk factors for perioperative blood transfusions. The area under the ROC curve (AUROC; C-statistic) was 0.759 (p<0.001), indicating relatively strong discriminatory ability/predictability of the final model.
UNASSIGNED: Several independent risk factors including age ≥60 years, preoperative blood transfusions and extended operative times increased risk for blood transfusion following single-level ALIF. The present study aims to help surgeons identify high-risk patients to better communicate postoperative expectations and optimize patients to reduce the risk of transfusions and secondary complications. Level of Evidence: III.

UNASSIGNED: Anterior lumbar interbody fusion (ALIF) or transforaminal lumbar interbody fusion (TLIF) may be used to correct the lumbosacral fractional curve (LsFC) in de novo adult (thoraco) lumbar scoliosis. Yet, the relative benefits of ALIF and TLIF for LsFC correction remain largely undetermined.
UNASSIGNED: To compare the currently available data comparing radiographic correction of the LsFC provided by ALIF and TLIF of LsFC in adult (thoraco)lumbar scoliosis.
UNASSIGNED: A systematic review was performed on original articles discussing fractional curve correction of lumbosacral spinal deformity (using search criteria: \"lumbar\" and \"fractional curve\"). Articles which discussed TLIF or ALIF for LsFC correction were presented and radiographic results for TLIF and ALIF were compared.
UNASSIGNED: Thirty-one articles were returned in the original search criteria, with 7 articles included in the systematic review criteria. All 7 articles presented radiographic results using TLIF for LsFC correction. Three of these articles also discussed results for patients whose LsFC were treated with ALIFs; 2 articles directly compared TLIF and ALIF for LsFC correction. Level III and level IV evidence indicated ALIF as advantageous for reducing the coronal Cobb angle of the LsFC. There were mixed results on relative efficacy of ALIF and TLIF in the LsFC for restoration of adequate global coronal alignment.
UNASSIGNED: Limited level III and IV evidence suggests ALIF as advantageous for reducing the coronal Cobb angle of the LsFC in de novo adult (thoraco) lumbar scoliosis. Relative efficacy of ALIF and TLIF in the LsFC for restoration of global coronal alignment may be dictated by several factors, including directionality and magnitude of preoperative coronal deformity. Given the limited and low-quality evidence, additional research is warranted to determine the ideal interbody support strategies to address the LsFC in adult (thoraco) lumbar scoliosis.