North American Spine Society Journal最新文献

{"title":"Ten-year analysis of 17,639 thoracolumbar instrumentation failures using the manufacturer and user facility device experience (MAUDE) database","authors":"Gil Kimchi MD ,&nbsp;Darcy Johnston ,&nbsp;John Paul G. Kolcun MD ,&nbsp;Jill Serbousek ,&nbsp;Richard G. Fessler MD, PhD","doi":"10.1016/j.xnsj.2026.100861","DOIUrl":"10.1016/j.xnsj.2026.100861","url":null,"abstract":"<div><h3>Background</h3><div>This study utilized the FDA-maintained Manufacturer and User Facility Device Experience (MAUDE) database, an extensive resource capturing medical device reports (MDRs) of adverse events, to perform a cross-sectional analysis of failure mechanisms reported by manufacturers.</div></div><div><h3>Methods</h3><div>All thoracolumbar pedicle screw system failures reported in the MAUDE database between January 2014 and December 2023 were identified using FDA product codes. Failures were classified as intraoperative or postoperative and grouped into 9 and 5 clusters, respectively. Following de-identification, the 8 most frequently reported manufacturers were analyzed individually. Reports specifying failed components were categorized as screw, set screw, rod, instrument, system, other, or unknown. The “system failure” category lacked specificity regarding the failed component. Descriptive statistics summarized failure mechanisms.</div></div><div><h3>Results</h3><div>A total of 17,639 MDRs related to thoracolumbar fixation failures were reported over the past decade, with 15,234 postoperative and 2,405 intraoperative events. The most frequent intraoperative issues were positioning problems (27.9%), device-device compatibility (26.4%), and difficulty in separation/removal (11.8%), while the most common postoperative failure mechanisms were breakage (45.2%), migration/detachment (42%), and deformation (10.1%). The distribution of failed components varied by the associated failure mechanism. Among 4,676 reported breakages, screws (20.8%), set screws (15.5%), and rods (11.8%) were most frequently involved. In the 4,871 migration/detachment events, set screws accounted for 31.6%, screws for 21%, and rods for 2.3%. Of 1,325 deformation events, the majority were linked to set screws (76.5%), with fewer attributed to system-level components (11.2%) and screws (6%).</div></div><div><h3>Conclusions</h3><div>Failure profiles for pedicle screw systems vary significantly between manufacturers. The MAUDE database is a useful resource for the evaluation of reporting patterns associated with pedicle screw systems. However, limitations include reporting biases and the absence of total sales data, which prevents the calculation of true failure rates.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"25 ","pages":"Article 100861"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147396082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Following posterior spinal fusion for adolescent idiopathic scoliosis, patients with asthma are at increased odds of pulmonary adverse events","authors":"Lucas Y Kim BS,&nbsp;Julian Smith-Voudouris MSc,&nbsp;Scott J Halperin MD MHS,&nbsp;Dominick Tuason MD,&nbsp;Jonathan N Grauer MD","doi":"10.1016/j.xnsj.2025.100833","DOIUrl":"10.1016/j.xnsj.2025.100833","url":null,"abstract":"<div><h3>Background</h3><div>Posterior spinal fusion (PSF) is a highly successful treatment for adolescent idiopathic scoliosis (AIS). Asthma is one of the most common illnesses affecting young patients and has been shown to affect outcomes in orthopedic procedures. The correlation of asthma and postoperative adverse outcomes following PSF had not been well characterized.</div></div><div><h3>Methods</h3><div>Adolescent patients undergoing PSF for AIS between 2015 and 2023 were identified using the national administrative PearlDiver M165 database. Those with versus without asthma were matched 1:4 based on demographic and comorbid factors and compared for incidence of 90-day postoperative adverse events using multivariable logistic regression. Revision surgery within 5 years was compared using Kaplan–Meier analysis and the log-rank test.</div><div>Secondary multivariable analysis was performed comparing odds of 90-day postoperative adverse events for different levels of asthma severity (mild intermittent, mild persistent, moderate/severe) relative to non-asthma patients.</div></div><div><h3>Results</h3><div>Of 10,196 PSF patients meeting study criteria, asthma was noted for 1,616 (15.8%). After matching, those with asthma were at higher odds of respiratory failure (odds ratio [OR] 1.98, p &lt; .001), pneumonia (OR 1.72, p = .004), and atelectasis (OR 1.52, p = .002), as well as emergency department visit (OR 1.66, p &lt; .001) and readmissions (OR 1.58, p &lt; .001). Differences were not identified for non-pulmonary adverse events. As asthma severity increased from mild intermittent, to mild persistent, to moderate/severe, odds ratios incrementally increased pneumonia (OR not significant, not significant, 4.52, respectively), respiratory failure and atelectasis (OR not significant, not significant, 2.38, respectively) (p &lt; .05 for each listed).</div></div><div><h3>Conclusion</h3><div>Overall, asthma is a common comorbidity for adolescent patients undergoing PSF for AIS and is associated with higher odds of postoperative pneumonia, respiratory failure, and atelectasis. These adverse outcomes increase with increased asthma severity. These findings may help in patient counselling and expectations for postoperative management.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"25 ","pages":"Article 100833"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extraforaminal lumbar interbody fusion: A systematic review of clinical outcomes, fusion rates, and safety profile","authors":"Michael K. Coffin BS,&nbsp;Kyle A. McGrath DO,&nbsp;Rebecca M. Garner MD,&nbsp;Christiana M. Cornea MD,&nbsp;Joseph S. Cheng MD,&nbsp;Justin N. Virojanapa DO","doi":"10.1016/j.xnsj.2025.100830","DOIUrl":"10.1016/j.xnsj.2025.100830","url":null,"abstract":"<div><h3>Background</h3><div>Extraforaminal lumbar interbody fusion (ELIF) accesses the disc through a posterolateral extraforaminal corridor that preserves the posterior ligamentous complex and avoids abdominal exposure. The objective of this systematic review is to synthesize the clinical outcomes, fusion rates, complications, and surgical indications for ELIF.</div></div><div><h3>Methods</h3><div>PRISMA 2020–conformant review registered in PROSPERO (ID: 1111090). Eligible studies reported clinical or radiographic outcomes of ELIF performed via the posterolateral extraforaminal approach. Extracted variables included indications, operative time, patient-reported outcomes, fusion, and complications. Risk of bias was assessed with the Newcastle–Ottawa Scale (NOS).</div></div><div><h3>Results</h3><div>Thirteen retrospective studies (n=518) met inclusion. The quality of studies included was generally fair, as graded by Newcastle–Ottawa Scale (NOS). The most common indication was degenerative disc disease. Mean operative time was 168.7 minutes. Fusion by technique: open pooled mean 98%, minimally invasive pooled mean 84%, and endoscopic 100% in a single series. Pooled VAS back improved as follows: open 6.27 to 2.80 (Δ 3.47; mean follow-up 12.8 months), minimally invasive 8.16 to 3.52 (Δ 4.64; 18.8 months), endoscopic 6.49 to 1.66 (Δ 4.83; 13.2 months). Pooled VAS leg improved: open 6.66 to 2.35 (Δ 4.31, 13.3 months), minimally invasive 8.66 to 2.17 (Δ 6.49; 15.5 months), endoscopic 6.60 to 1.50 (Δ 5.10; 14.2 months). Pooled Oswestry disability index (ODI) improved: open 60.17 to 26.25 (Δ 33.92; 9.5 months), minimally invasive 56.02 to 21.46 (Δ 34.56; 18.8 months), endoscopic 34.59 to 12.19 (Δ 22.40; 13.2 months). Transient radiculopathy was reported at 9.5% and dural tear at 0.5%.</div></div><div><h3>Conclusions</h3><div>As the first systematic review on ELIF, findings indicate it is a safe, effective alternative for lumbar fusion in select patients. Success necessitates favorable extraforaminal anatomy and intraoperative nerve monitoring to minimize complications. Future prospective trials are essential to validate these outcomes and standardize patient selection criteria.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"25 ","pages":"Article 100830"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bed break-induced attenuation of downside leg sciatic nerve sensory and motor evoked potentials during lateral lumbar interbody (LLIF) fusion surgery","authors":"David W Allison PhD, CNIM ,&nbsp;Amit Verma MD ,&nbsp;Anthony R Cockrell CNIM ,&nbsp;Todd Trask MD ,&nbsp;William J Steele MD ,&nbsp;Loyola V Gressot MD ,&nbsp;Suraj Sulhan MD ,&nbsp;Ryan P Cantrell BS ,&nbsp;Jaime R Guerrero MD ,&nbsp;Brandy B Ma MD ,&nbsp;Amir H Faraji MD, PhD ,&nbsp;Mark L Prasarn MD ,&nbsp;Adam Green MD ,&nbsp;Comron Saifi MD ,&nbsp;Sean M Barber MD ,&nbsp;Meng Huang MD ,&nbsp;Paul Holman MD","doi":"10.1016/j.xnsj.2025.100831","DOIUrl":"10.1016/j.xnsj.2025.100831","url":null,"abstract":"<div><h3>Background</h3><div>Multimodality intraoperative neuromonitoring (IONM) is used to map and monitor the femoral plexus during transpsoas lateral lumbar interbody fusion (LLIF) surgery. Approach side LLIF IONM alerts that portend a femoral plexopathy have been well-studied, but downside sciatic nerve distribution alerts have not been reported. The breaking of the bed to obtain better access to the disc space can cause attenuation of downside leg sciatic nerve distribution somatosensory, transcranial, and transabdominal motor evoked potentials (SSEPs, TcMEPs, and TaMEPs) and appears most common in females with a BMI ≥ 30. We evaluated the propensity and cause of downside leg sciatic nerve distribution SSEP, TcMEP, and TaMEP alerts during LLIF surgery.</div></div><div><h3>Methods</h3><div>A single-center 30-month retrospective examined the frequency of downside leg sciatic nerve distribution IONM alerts for 692 patients, 380 female (55%) and 312 male (45%), having LLIF spine surgery utilizing IONM consisting of SSEPs, TcMEPs, TaMEPs, electromyography (EMG) and electroencephalography (EEG). Downside leg IONM alerts were analyzed for correlation to patient BMI, sex, age, as well as the recovery of IONM signals to the length of time the bed remained broken. IONM data was correlated to immediate postoperative neurological evaluations and chart reviews.</div></div><div><h3>Results</h3><div>Of 692 LLIF surgeries, 18 (2.6%) downside leg sciatic nerve distribution SSEP, TcMEP, and TaMEP alerts were observed. No cases detected concomitant IONM changes involving downside-leg femoral nerve distribution. The attenuation and recovery of the downside leg sciatic nerve distribution IONM responses during these alerts appeared to correlate to the breaking and unbreaking of the bed. Of the 18 alerts, 17 occurred in females, 12 in females with BMI ≥ 30, and 16 in patients aged 60 or older. Chi-square analysis points to sex (female) and obesity (BMI ≥ 30) as characteristics that correlate to this phenomenon. Interestingly, none of the 18 patients, including the 2 where IONM responses did not return to baseline, suffered postoperative downside leg sciatic distribution motor or sensory deficits.</div></div><div><h3>Conclusions</h3><div>The possible mechanism of these downside leg alerts is compression or stretch of the sciatic nerve at the level of the pelvis, not leg ischemia. While none of the 18 alert case patients suffered postoperative deficits, best practice would be to partially or completely unbreak the bed as soon as feasible when the downside sciatic nerve distribution IONM signals are attenuated.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"25 ","pages":"Article 100831"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145925986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A systematic review and meta-analysis of sagittal cervical spine parameters: Normative values, correlation with quality of life, and biomechanical modeling","authors":"Vinicius Ricieri Ferraz MD ,&nbsp;Carlos R. Goulart MD ,&nbsp;Tobias Alecio Mattei MD, FACS","doi":"10.1016/j.xnsj.2025.100819","DOIUrl":"10.1016/j.xnsj.2025.100819","url":null,"abstract":"<div><h3>Background</h3><div>The sagittal alignment of the cervical spine is pivotal for spinal biomechanics, head positioning, and overall spinal balance. This systematic review synthesizes the available evidence on sagittal cervical spine parameters, establishing normative values in asymptomatic populations, evaluating their correlation with health-related quality of life, and exploring biomechanical modeling to understand their functional implications.</div></div><div><h3>Methods</h3><div>A systematic literature search was conducted in PubMed/MEDLINE (January 2010–May 2025) following PRISMA guidelines. Key cervical alignment parameters were identified, including C2–C7 Cobb angle, C2–C7 sagittal vertical axis (SVA), T1 slope (T1S), T1 slope minus cervical lordosis (T1S–CL), C2 slope, neck tilt, cranial tilt, and spino-cranial angle (SCA). After screening 500 articles, 20 studies meeting predefined inclusion criteria were analyzed. Data on normative values, correlations with HRQoL scores and findings from biomechanical modeling were extracted. A meta-analysis was performed to establish normative values in the asymptomatic population.</div></div><div><h3>Results</h3><div>Normative values were derived from meta-analyses, and statistical correlations were used to link the cervical spine parameters under study to HRQoL metrics such as the Neck Disability Index (NDI), EuroQol 5 Dimension (EQ-5D), and Short Form-36 (SF-36). Deviations, particularly C2–C7 SVA &gt; 40 mm and T1S–CL &gt; 15–20°, were significantly associated with reduced HRQoL. Biomechanical modeling techniques, including finite element (FE) and multibody dynamics approaches, provide further insights into spinal loading and stress distribution in the setting of abnormal cervical spinal alignment.</div></div><div><h3>Conclusions</h3><div>Quantitative evidence shows that cervical alignment is prognostically decisive rather than merely descriptive. Across several clinical cohorts, a C2–7 sagittal vertical axis &gt; 40 mm or a T1-slope minus cervical-lordosis mismatch &gt; 15–20° consistently predicted clinically meaningful disability as measured by NDI, EQ-5D and SRS-22. These thresholds, supported by biomechanical modelling, define actionable targets for surgical planning, rehabilitation and long-term follow-up. Standardized measurement protocols and patient-specific reference ranges are now the critical next steps to transform these radiographic markers into personalized care pathways and prospective interventional trials.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"25 ","pages":"Article 100819"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145697937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying patients at risk for a facility discharge following elective one or two level lumbar fusion","authors":"Matthew J. Solomito PhD ,&nbsp;Heeren Makanji MD ,&nbsp;Jesse Eisler MD","doi":"10.1016/j.xnsj.2025.100786","DOIUrl":"10.1016/j.xnsj.2025.100786","url":null,"abstract":"<div><h3>Background</h3><div>Spine procedures are becoming increasingly common and costly in the United States, thus managing fiscal responsibility with surgical outcomes is increasingly important. Reducing facility discharges following a lumbar fusion would not only reduce complications but could provide significant cost savings. Therefore, the purpose of this study is to identify both clinical factors (i.e. demographics, medical history factors) and patient reported outcome scores that were associated with an increased risk of a facility-based discharge following an elective 1 or 2 level lumbar fusion.</div></div><div><h3>Methods</h3><div>A total of 513 patients that underwent a 1- or 2-level lumbar fusion between June 2021 and June 2023 were included in this retrospective study. All patients completed their preoperative PROs and completed their medical history and physical prior to surgery. Using logistic regressions, independent variables associated with postoperative discharge to a skilled nursing facility were identified. Subsequent receiver operator curve analysis helped determine cut point values associated with a facility discharge.</div></div><div><h3>Results</h3><div>A total of 41 patients (7.9%) were discharged to a facility. Regression analysis identified 6 factors associated with a facility discharge. Three factors were related to clinical outcomes while the other 3 factors were obtained from patient reported outcomes measures. More specifically, PROMIS-10 Global physical (OR:0.17,95% CI 0.04–0.62, AUC:0.701) and mental health (OR:0.89,95% CI 0.83–0.95, AUC:0.813) T-scores below 40, and RAPT scores below 9 (OR:0.60,95% CI 0.48–0.74, AUC:0.814) were associated with facility-based discharges.</div></div><div><h3>Conclusions</h3><div>Patient reported outcomes measures provide significant discriminatory ability in combination with standard clinical metrics to identify patients at risk for a facility discharge following elective lumbar fusions. The results suggested that patient reported information concerning preoperative mobility, mental wellbeing, and support at home were more discriminatory than clinical metrics.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"24 ","pages":"Article 100786"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implant density reduction to avoid proximal junctional failure in adult spine surgery: Computer models and simulations","authors":"Morteza Rasouligandomani PhD ,&nbsp;Alex del Arco MD-PhD ,&nbsp;Tomaso Villa PhD ,&nbsp;Luigi La Barbera PhD ,&nbsp;Miguel A. González Ballester PhD ,&nbsp;Fabio Galbusera PhD ,&nbsp;Jérôme Noailly PhD","doi":"10.1016/j.xnsj.2025.100770","DOIUrl":"10.1016/j.xnsj.2025.100770","url":null,"abstract":"<div><h3>Background</h3><div>Proximal Junctional Failure (PJF) is a common complication in Adult Spine Deformity (ASD) surgeries, often leading to reoperations. While revision surgeries with osteotomies carry high complication rate of 34.8%, alternatives such as hardware proximal extension may increase PJF risk in patients with severe Global Alignment and Proportion (GAP) scores. Implant Density Reduction (IDR) has emerged to mitigate PJF risk. This study assessed the impact of IDR on PJF risk and explored sub-optimal strategies.</div></div><div><h3>Methods</h3><div>Two patient-personalized Finite Element (FE) models were used and expanded into a virtual cohort. Implant Density (ID), rod material, bone quality, and GAP were systematically varied. Thoracolumbar FE models were developed using structured Statistical Shape Modeling (SSM). Biomechanical metrics of Intervertebral Disk (IVD) fiber strain, Screw Pull-out Force (SPF), and rod stress, were evaluated. Trade-off analyses could determine sub-optimal configurations avoiding PJF.</div></div><div><h3>Results</h3><div>IDR significantly decreased IVD strain (up to −70%) and improved screw stability (up to +142%), for patients with titanium (Ti) rods and normal bone. However, IDR effectiveness was limited for cases with GAP ≥12, osteoporotic bone, and Cobalt-Chromium (Cr-Co) rods. No IDR strategy could prevent PJF for cases with GAP 12 or 13, regardless of rod type. For cases with GAP 11 and Upper Instrumented Vertebra (UIV) at T10, IDR was effective with only Ti rods. For cases with GAP 13 and UIV at T3, none of IDRs, independent of rod material, offered benefit. Notably, Ti rods may support IDR-based risk reduction in borderline cases, such as GAP 12, UIV at T3.</div></div><div><h3>Conclusions</h3><div>IDR is a promising strategy to lower PJF risk in high-risk spine revision cases, though its effectiveness depends on surgical and anatomical factors. This study provides an in-silico tool to support personalized surgical planning and guide future clinical trials aimed at reducing reoperations and healthcare costs.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"24 ","pages":"Article 100770"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of metabolic syndrome on one-year patient-reported outcomes after lumbar fusion surgery","authors":"Jack Parker BS,&nbsp;Jane C. Brennan MS,&nbsp;Andrea H. Johnson MSN, CRNP,&nbsp;Chad M. Patton MD, MS,&nbsp;Justin J. Turcotte PhD, MBA","doi":"10.1016/j.xnsj.2025.100785","DOIUrl":"10.1016/j.xnsj.2025.100785","url":null,"abstract":"<div><h3>Background</h3><div>The prevalence of Metabolic Syndrome (MetS) is increasing and negatively impacts a variety of surgeries. In lumbar fusions, MetS is associated with an increased risk of complications, however no studies have focused on patient-reported outcome measures (PROMs). The aim of this study was to explore the relationship between MetS and 1-year PROMs in lumbar fusion patients using the Patient-Reported Outcomes Measurement Information System (PROMIS).</div></div><div><h3>Methods</h3><div>Retrospective review of 212 patients who underwent 1- to 3-level lumbar fusion for degenerative pathologies between March 2021 and December 2023 from a single institution was performed. Patients were categorized based on the presence of MetS, defined as having 3 or more qualifying metabolic conditions, and assessed using PROMIS surveys (Physical Function [PF], Mental Health, and Pain Interference) preoperatively and at 1-year postoperatively. Univariate and multivariate analyses were performed to evaluate the impact of MetS on PROMIS improvement.</div></div><div><h3>Results</h3><div>Patients with MetS (<em>n</em>=64, 30.2%) had a longer length of stay, were more likely to be discharged to a skilled nursing facility, and experienced higher rates of 1-year complications (37.5vs. 20.9%, p=.016). After risk-adjustment, MetS patients had lower odds of achieving clinically significant improvement in PROMIS-PF (OR: 0.46, p=.020). In obese patients, the presence of MetS was associated with less improvement (β: -3.22, p=.049) and lower odds of clinically significant improvement in PROMIS-PF (OR: 0.34, p=.017). No significant associations between MetS and mental health or pain interference scores were observed in the overall population or obese patients.</div></div><div><h3>Conclusions</h3><div>MetS negatively impacts outcomes following lumbar fusion, and this difference in outcomes is not solely explained by obesity. Patients should be encouraged to modify their lifestyle to reduce the adverse effects of MetS on outcomes, and surgeons should consider the impact of MetS on outcomes following lumbar fusion and communicate these expectations with patients.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"24 ","pages":"Article 100785"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Higher screw-to-cage length ratios in standalone lateral interbody fusion using integrated, expandable implants provide more predictable outcomes with less variability: A 2-year follow-up study","authors":"Dean T. Biddau BBiomedSci ,&nbsp;Dean P. McKenzie BA (Hons) PhD ,&nbsp;Nigel R. Munday MBBS, MBA ,&nbsp;Gregory M. Malham BSc, MBChB, DMed, FRACS","doi":"10.1016/j.xnsj.2025.100817","DOIUrl":"10.1016/j.xnsj.2025.100817","url":null,"abstract":"<div><h3>Background Context</h3><div>Lateral Lumbar Interbody Fusion (LLIF) is widely used for degenerative spinal disorders. Standalone LLIF with expandable cages integrating plate-screw fixation (eLLIFp) has emerged to address disc degeneration and adjacent segment disease while reducing the need for posterior fixation. Biomechanical data suggest greater stability with longer screws, but the clinical impact of screw-to-cage length ratios remains unclear. This study evaluates outcomes following eLLIFp and investigates whether screw-to-cage ratios influence results.</div></div><div><h3>Methods</h3><div>Eighty-one patients (87 levels) underwent eLLIFp, mean age 63.8±10.8 years (49.4% female), BMI 27.7±4.9 kg/m². Common levels treated were L2/3 (35%) and L3/4 (29%). Mean retractor time was 30.2±5.5 min. Retrospective analysis of prospectively collected data examined integrated screw length (30–60 mm) and cage length (50–65 mm). Screw-to-cage ratios were grouped into tertiles: Low (0.46–0.75, n=36), Medium (0.76–0.82, n=18), and High (0.83–1.0, n=27). Outcomes included pain (VAS), disability (ODI), quality of life (SF-12), and fusion status on 12-month CT. Minimum follow-up was 2 years.</div></div><div><h3>Results</h3><div>At 12 months, all patients showed significant improvement (p&lt;0.0001) [VAS back: 7.6→0.9; VAS leg: 6.3→0.7; ODI: 25.7→5.1; SF-12 PCS: 29.9→49.2; MCS: 37.3→55.6]. Improvements were comparable across tertiles, though the high-ratio group exhibited less variability in leg pain outcomes. Fusion was achieved in 79/81 (97.5%) patients. Complications occurred in 5 (6.2%): 3 neurological (motor radiculopathy, radicular pain, transient thigh numbness) and 2 symptomatic nonunions requiring posterior fixation, both with lower screw-to-cage ratios (0.7).</div></div><div><h3>Conclusions</h3><div>Higher screw-to-cage ratios (0.83–1.0) in standalone eLLIFp constructs may enhance consistency in leg pain relief without increasing complications. Maximizing screw length relative to cage dimensions may optimize outcomes and reduce variability in standalone LLIF.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"24 ","pages":"Article 100817"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145568232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does psoas size predict postoperative thigh pain in extreme lateral interbody fusion?","authors":"Najim Yusof MBBS, MRCS,&nbsp;Chang Yi Woon MBBS,&nbsp;Han Xinyun Audrey MBBS, MRCS, MMed Ortho, FRCS,&nbsp;Soh Chee Cheong Reuben MBBS, MRCS, MMed Ortho, FRCS","doi":"10.1016/j.xnsj.2025.100783","DOIUrl":"10.1016/j.xnsj.2025.100783","url":null,"abstract":"<div><h3>Background</h3><div>Lateral lumbar interbody fusion via a transpsoas approach is designed to reduce the morbidity of open spinal surgeries and achieve lordosis targets in fusion. A common postoperative finding is thigh dysesthesia and weakness. However, there has not been much research into factors contributing to the thigh dysesthesia and weakness. This study aims to assess the association between psoas size and postoperative thigh and/or groin pain.</div></div><div><h3>Methods</h3><div>A prospectively collected retrospectively analyzed database of patients who had degenerative lumbar spinal stenosis who underwent transpsoas lumbar interbody fusion at a single institution was evaluated. We included patients who had XLIF to either L3/4 and/or L4/5 and excluded patients who did not have preoperative MR imaging scans available in our electronic health records. Patients with previous lumbar surgeries and history of infection to the lumbar spine and psoas were excluded. 80 patients met the inclusion criteria. We tested the association between the presence of postoperative thigh and/or groin pain with the following factors: psoas muscle dimension, gender, age, BMI and length of psoas retraction time using One-way ANOVA or Chi-square test or Fisher Exact test where appropriate.</div></div><div><h3>Results</h3><div>A total of 80 patients met the inclusion criteria. Anterior-posterior diameter of the psoas (p = .011–.013) was found to have a statistically significant relationship with postoperative thigh and/or groin pain for patients who underwent transpsoas lumbar interbody fusion at multiple levels.</div></div><div><h3>Conclusions</h3><div>When considering patients for multilevel lateral lumbar spine surgery, MRI evaluation of anterior-posterior diameter of psoas size and gender of patient is helpful in predicting cases with higher risk of developing postoperative thigh pain. When anterior-posterior psoas diameter is more than 49.51 mm (for multiple level surgeries), consideration to approach via an anterior to psoas lateral approach or greater discussion with postoperative expectation would be warranted.</div></div>","PeriodicalId":34622,"journal":{"name":"North American Spine Society Journal","volume":"24 ","pages":"Article 100783"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145614553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}