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Purpose: Posterior spinal fusion (PSF) is the current gold standard in surgical treatment for adolescent idiopathic scoliosis. Vertebral body tethering (VBT) is a fusionless alternative. Shoulder balance is an important metric for outcomes and patient satisfaction. Here we compare shoulder balance outcomes between PSF and VBT. Methods: In this retrospective review, the pre-operative and post-operative absolute radiographic shoulder height (|RSH|) of 45 PSF patients were compared to 46 VBT patients. Mean values were compared and then collapsed into discrete groups (|RSH| GROUP) and compared. Patients were propensity score matched. Regression models based on pretest–posttest designs were used to compare procedure type on post-operative outcomes. Results: Pre-operatively there were no differences in |RSH| between PSF and VBT, however, at latest post-operative follow-up PSF maintained a larger |RSH| imbalance compared to VBT (0.91 cm vs 0.63 cm, p = 0.021). In an ANCOVA regression, PSF was associated with a larger |RSH| imbalance compared to VBT, F(1, 88) = 5.76, p = 0.019. An ordinal logistic regression found that the odds ratio of being in a worse |RSH| GROUP for PSF vs VBT is 2.788 (95% CI = 1.099 to 7.075), a statistically significant effect χ2(1) = 4.658, p = 0.031. Results were similar in subgroup analyses of Lenke 1 and Lenke 2 patients, though to less statistical significance. Conclusion: While PSF was found to be associated with worse |RSH| outcomes, the actual numbers (2–3 mm) are unlikely to be clinically meaningful. Thus, in this analysis, VBT can be said to show comparable shoulder balance outcomes to PSF.

Background: There is significant debate regarding the indications of staged surgery for severe adolescent spinal deformity, and the factors associated with the decision to perform staged compared to same-day surgery have not been previously investigated. Thus, the purpose of this study was to determine which factors were most strongly associated with this decision. Methods: A prospective multicenter registry of adolescent patients with severe spinal deformity was reviewed. Two cohorts were identified: those who underwent a planned staged surgical procedure for deformity correction and those who underwent a same-day procedure. Patients who underwent an unplanned staged procedure secondary to complications during the initial procedure were excluded. Comparisons were made between these cohorts with respect to preoperative patient and radiographic variables to determine which factors were associated with the decision to perform a staged procedure. Surgical data was also compared to evaluate for differences in the intraoperative management of staged versus same-day patients. Results: Two hundred and twenty-nine patients with severe spinal deformities were identified. Forty patients (17%) underwent a planned staged procedure and 189 patients (80%) underwent a same-day procedure. On univariate analysis of preoperative variables, patients who underwent staged surgery had a significantly younger age at surgery, greater major curve magnitude, greater major curve AVT to CSVL, lesser thoracic spine height, greater radiographic trunk shift, and a greater proportion of patients undergoing revision surgery (as opposed to primary correction) compared to those who underwent a planned single-stage procedure. Multivariate logistic regression of pre-operative variables showed that age < 16 years, maximum cobb angle ≥ 120 degrees, major curve AVT to CSVL of ≥ 3.5 cm, and revision surgery were independently associated with the decision to perform a staged procedure. Intraoperatively, patients in the staged cohort more frequently underwent combined anterior and posterior procedures, grade 4 or higher Schwab osteotomies, and had a greater number of levels fused. Conclusion: There is substantial variability with respect to the decision to perform surgery for severe adolescent spine deformities in a staged versus same-day fashion. This large analysis of prospectively collected data is the first to describe the factors most strongly associated with the decision to perform a staged procedure and may help guide the surgical decision-making for these patients.

Purpose: In patients with adolescent idiopathic scoliosis (AIS) undergoing anterior vertebral tethering (AVBT), some will subsequently require posterior spinal fusion (PSF). Limited data exist on clinical and radiographic outcomes of fusion after tether failure. Methods: 490 patients who underwent AVBT were retrospectively analyzed. Twenty patients (4.1%) subsequently underwent conversion to PSF. A control group of patients with primary PSF (no previous AVBT) was matched for comparison. Data were compared using paired t-tests and Fisher Exact Tests. Results: There was a significant increase in estimated blood loss (EBL) (p= 0.002), percent estimated blood volume (%EBV) (p= 0.013), operative time (p= 0.002), and increased amount of fluoroscopy (mGy) (p= 0.04) as well as number of levels fused (p= 0.02) in the AVBT conversion group compared to primary fusion. However, no difference was found in implant density (p= 0.37), blood transfusions (p= 0.11), or intraoperative neuromonitoring events (p> 0.99). Both groups attained similar thoracic and lumbar percent correction (major coronal curve angle) from pre-op to the latest follow-up (thoracic p= 0.507, lumbar p= 0.952). Conclusion: A subset of patients with AVBT will require conversion to PSF. Although technically more challenging, revision surgery can be safely performed with similar clinical and radiographic outcomes to primary PSF. Level of evidence: 3.

Study design: Retrospective review of a prospectively collected multicenter registry of pediatric patients with cerebral palsy (CP) and neuromuscular scoliosis (NMS) undergoing spinal fusion. Objective: To define risk factors for unplanned readmission after elective spinal deformity surgery. Summary of background data: Patients with CP and NMS have high rates of hospital readmission; however, risk factors for readmission are not well established. Methods: Univariate and multivariate analyses were used to compare the demographics, operative and postoperative course, radiographic characteristics, and preoperative Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) questionnaires of patients who did not require readmission to those who required either early readmission (within 90 days of the index surgery) or late readmission (readmission after 90 days). Results: Of the 218 patients identified, 19 (8.7%) required early readmission, while 16 (7.3%) required late readmission. Baseline characteristics were similar between the three cohorts. On univariate analysis, early readmission was associated with longer duration of surgery (p< 0.001) and larger magnitude of residual deformity (p= 0.003 and p= 0.029 for postoperative major and minor angles, respectively). The health score of the CPCHILD Questionnaire was lower in patients who required early readmission than in those who did not require readmission (p= 0.032). On multivariate analysis, oral feeding status was inversely related to early readmission (less likely to require readmission), while decreasing lumbar lordosis and increasing length of surgery were related to an increased likelihood of early readmission. Conclusions: In patients with CP and NMS, longer surgical time, larger residual major and minor Cobb angles, lumbar lordosis, feeding status, and overall health may be related to a greater likelihood for early hospital readmission after elective spinal fusion. No factors were identified that correlated with an increased need for late hospital readmission after elective spinal fusion in patients with CP. Level of evidence: IV.

Background: Multiple studies have reported on the risks and preventative measures associated with acute surgical site infection (SSI) in patients with adolescent idiopathic scoliosis (AIS). Few studies have evaluated treatment and results. The purpose of this study was to evaluate the need for development of best practice guidelines based on the management of an acute SSI across 9 different centers. Methods: A prospectively collected, multicenter database of patients undergoing surgical correction of AIS was reviewed for all acute SSI. Infection characteristics, treatment methods, and outcomes were summarized. Results: Twenty-three (0.6%) from a total of 3926 AIS patients were treated for an acute SSI, all of which resolved. Twenty patients had documentation of the infection treatment (10 deep infections, 10 superficial). All ten patients with deep infections underwent operative incision and drainage. Six patients ultimately found to have a superficial infection underwent I&D and another 3 had dressing changes in the office. In the deep group, one patient had instrumentation exchanged and seven patients had bone graft removed. All 16 patients who underwent operative I&D had cultures obtained with 11 positive cultures. All deep infection patients were started on IV antibiotics for 2 days to 6 weeks prior to conversion to oral antibiotics. Five of six operative superficial infections were begun on IV antibiotics with conversion to oral antibiotics. Total antibiotic administration ranged from 5 days to 7 months in the deep infection group and 1 to 6 weeks in the superficial group. Conclusions: While deep infections are consistently treated with I&D, there is significant variability in the surgical and medical management of acute SSI. Considering the universal resolution of the infection, there is opportunity for the development of BPG to minimize treatment morbidity and cost, while optimizing outcomes for this major complication. Level of evidence: Therapeutic-IV.

Introduction: The evolution of MCGR technique has led to modifications in the configuration of the proximal construct to decrease the incidence of implant-related complications (IRC) and revision surgeries. However, there is no data characterizing the performance of the most used configurations reducing the risk of complications. Methods: 487 patients were identified from an international multicenter EOS database. Inclusion criteria: EOS patients, primary dual MCGR, complete radiographs, and minimum of 2-year follow-up. 76 patients had incomplete X-rays, 5 had apical fusions, and 18 had inconclusive complications, leaving 388 patients for review. A digital spine template was created to document UIV; number of levels; number, type, and location of anchors; as well as implant configuration. First available postoperative and latest follow-up radiographs were reviewed by two senior surgeons and two spine fellows. UPROR due to IRC was defined as any change in proximal anchors between the postoperative and final follow-up radiographs. Results: The most common proximal construct configuration: UIV at T2 (50.0%) with 17.5% UPROR, followed by T3 (34.0%) with 12.1% UPROR; number of levels was three (57.1%) with 16.8% UPROR and two (26.0%) with 17.0% UPROR; number of proximal anchors was six (49.9%) with 14.1% UPROR and four (27.0%) with 18.3% UPROR. The most common anchors were all screws (42.0%) with 9.9% UPROR, and all hooks (26.4%) with 31.4% UPROR (P< 0.001). The construct with the lowest rate of UPROR was a UIV at T2, with six anchors (all screws) across three levels (42 cases), with 0% UPROR. Other construct combinations that yielded 0% UPROR rates were UIV of T3, six anchors (all screws) across three levels (25 cases), and a UIV of T3 with six anchors (screws and hooks) across three3 levels (9 cases). Conclusion: Proximal anchor configuration impacts the incidence of UPROR due to IRC in MCGR. UIV at T2 and T3 compared to T4, and the use of all screws or combination of screws and hooks compared to all hooks were associated with a lower UPROR rate. The most common construct configuration was T2 UIV, three levels, six anchors, and all screws. The use of a combination of six anchors (screws or screws and hooks) across three levels with a UIV at T2 or T3 was associated with a lower UPROR rate. Additional research is needed to further evaluate the variables contributing to configuration selection and their association with IRC.

Study design: Cross sectional Objectives: The purpose of this study is to evaluate the association between thoracic height and health-related quality of life (HRQoL) at skeletal maturity in patients with EOS. Summary of background data: Current literature suggests a minimum thoracic height of 18 cm to 22 cm to avoid poor pulmonary function and related health outcomes. Methods: Patients with EOS who reached skeletal maturity from 2005 to 2018 were identified in two registries including 32 centers. Thoracic height from T1 to T12 at skeletal maturity and Early Onset Scoliosis 24 Item Questionnaire (EOSQ-24) scores were collected. The EOSQ-24 domains included HRQoL of patients, parental impact, financial impact and patient and parental satisfaction. Results: 469 patients (mean age: 14.9, female: 77.4%) were identified. 29% patients were of congenital etiology, 20.3% neuromuscular, 13.6% syndromic, 34.8% idiopathic, and 2.3% other. When patients were grouped by thoracic height at skeletal maturity, all EOSQ-24 domains increased after a threshold of 18 cm. When stratified by etiology, the 18 cm cutoff held for patients with congenital, neuromuscular and syndromic EOS. The cutoff for idiopathic EOS was 20 cm. For all patients, after the threshold was met, HRQoL continued to improve with increases in thoracic height at skeletal maturity. A subset of 169 patients for which arm span measurements were available was also identified and their thoracic heights were normalized. When grouped by the percentage of expected thoracic height attained, EOSQ-24 domains increased after a threshold of 80%. Conclusions: Once 18 cm of actual thoracic height or 80% of expected thoracic height is achieved, HRQoL continues to improve as thoracic height increases in skeletally mature patients with non-idiopathic EOS. Patients with idiopathic EOS had a higher threshold, possibly due to their larger average size and higher care giver expectations for HRQoL. Level of evidence: Level III.

Purpose: To evaluate intraoperative monitoring (IOM) alerts and neurologic deficits during severe pediatric spinal deformity surgery. Methods: Patients with a minimum Cobb angle of 100° in any plane or a scheduled vertebral column resection (VCR) with minimum 2-year follow-up were prospectively evaluated (n= 243). Preoperative, immediate postoperative, and 2-year postoperative neurologic status were reported. Radiographic data included preoperative and 2-year postoperative coronal and sagittal Cobb angles and deformity angular ratios (DAR). IOM alert type and triggering event were recorded. SRS-22r scores were collected preoperatively and 2-years postoperatively. Results: IOM alerts occurred in 37% of procedures with three-column osteotomy (n= 36) and correction maneuver (n= 32) as most common triggering events. Patients with IOM alerts had greater maximum kyphosis (101.4° vs. 87.5°) and sagittal DAR (16.8 vs. 12.7) (p< 0.01). Multivariate regression demonstrated that sagittal DAR independently predicted IOM alerts (OR 1.05, 95% CI 1.02–1.08) with moderate sensitivity (60.2%) and specificity (64.8%) using a threshold value of 14.3 (p< 0.01). IOM alerts occurred more frequently in procedures with new postoperative neurologic deficits (17/24), and alerts with both SSEP and TCeMEP signals were associated with new postoperative deficits (p< 0.01). Most patients with new deficits experienced resolution at 2 years (16/20) and had equivalent postoperative SRS-22r scores. However, patients with persistent deficits had worse SRS-22r total score (3.8 vs. 4.2), self-image subscore (3.5 vs. 4.1), and function subscore (3.8 vs. 4.3) (p≤ 0.04). Conclusion: Multimodal IOM alerts are associated with sagittal kyphosis, and predict postoperative neurologic deficits. Most patients with new deficits experience resolution of their symptoms and have equivalent 2-year outcomes. Level of evidence: II.

The article discusses the recent parliamentary election in Pakistan and raises concerns about the integrity of the electoral process. The author highlights instances of pre-election rigging, voter suppression, and manipulation of election results by the military and intelligence establishment. Despite these challenges, the Pakistan Tehreek-e-Insaf (PTI) party, led by former Prime Minister Imran Khan, emerged as the winner. The article calls on the Biden administration to support the democratic aspirations of the Pakistani people and reassess its relationship with the Pakistani military. It emphasizes the need for the US to stand in solidarity with the Pakistani people and demand a resolution of the irregularities in the election. [Extracted from the article]

AbstractLaetiporus versisporus(Lloyd) Imazeki is an edible mushroom that grows abundantly in kodaikanal hills (India) during rainy season. Till now, there is a dearth of reports on chemoprofile and anticancer potential of this mushroom. In our recent study, L.versisporusethanolic extract was reported to confer hepato-protective activity against DEN-induced HCC rats and also found to downregulate Bcl-2 activity. Moreover, the phytocompounds of a related species namely, L. sulphurousis also reported to potentially modulate Bcl-2 in glioblastoma. Hence, by this study, the bioactive compounds from L. versisporusethanolic extract were profiled using LC-MS analysis and were virtually screened against ligand binding site of Bcl-2 in order to predict potential moieties with anticancer efficacies. Further, the top 3 potential hits were shortlisted based on MMGBSA score, ADME properties and stable complex formation during MD simulation. Amongst these hits, (6S)-1alpha, 25-dihydroxy vitaminD36,19-sulfurdioxide adduct was found to be highly promising in terms of binding affinity and ADME features comparable to the known inhibitor (DRO), thus shall be further probed for therapeutic efficacy using experimental validations for effective and natural mode of combating Bcl-2 mediated cancers.Communicated by Ramaswamy H. Sarma

Study Design: Multi-center, prospective, observational cohort.Objective: To compare myelopathic vs. non-myelopathic ambulatory patients in short- and long-term neurologic function, operative treatment, and patient-reported outcomes.Methods: Pediatric deformity patients from 16 centers were enrolled with the following inclusion criteria: aged 10-21 years-old, a Cobb angle ≥100° in either the coronal or sagittal plane or any sized deformity with a planned 3-column osteotomy, and community ambulators. Patients were dichotomized into 2 groups: myelopathic (abnormal preoperative neurologic exam with signs/symptoms of myelopathy) and non-myelopathic (no clinical signs/symptoms of myelopathy).Results: Of 311 patients with an average age of 14.7 ± 2.8 years, 29 (9.3%) were myelopathic and 282 (90.7%) were non-myelopathic. There was no difference in age (P= 0.18), gender (P= 0.09), and Risser Stage (P= 0.06), while more patients in the non-myelopathic group had previous surgery (16.1% vs. 3.9%; P= 0.03). Mean lower extremity motor score (LEMS) in myelopathic patients increased significantly compared to baseline at every postoperative visit: Baseline: 40.7 ± 9.9; Immediate postop: 46.0 ± 7.1, P= 0.02; 1-year: 48.2 ± 3.7, P< 0.001; 2-year: 48.2 ± 7.7, P< 0.001). The non-myelopathic group had significantly higher LEMS immediately postoperative (P= 0.0007), but by 1-year postoperative, there was no difference in LEMS between groups (non-myelopathic: 49.3 ± 3.6, myelopathic: 48.2 ± 3.7, P= 0.10) and was maintained at 2-years postoperative (non-myelopathic: 49.2 ± 3.3, myelopathic: 48.2 ± 5.7, P= 0.09). Both groups improved significantly in all SRS domains compared to preoperative, with no difference in scores in the domains for pain (P= 0.12), self-image (P= 0.08), and satisfaction (P= 0.83) at latest follow-up.Conclusion: In severe spinal deformity pediatric patients presenting with preoperative myelopathy undergoing spinal reconstructive surgery, myelopathic patients can expect significant improvement in neurologic function postoperatively. At 1-year and 2-year postoperative, neurologic function was no different between groups. While non-myelopathic patients had significantly higher postoperative outcomes in SRS mental-health, function, and total-score, both groups had significantly improved outcomes in every SRS domain compared to preoperative.

The reactor containment building (RCB) in nuclear power plants (NPPs) plays an important role in protecting the reactor systems from external loads as well as preventing radioactive leaking. As we witnessed the nuclear disaster at Fukushima Daiichi (Japan) in 2011, the earthquake is one of the major threats to NPPs. The purpose of this study is to evaluate effects of concrete material models and presstressing forces on the seismic performance evaluation of RCB in NPPs. A typical RCB designed in Korea is employed for a case study. Detailed three-dimensional nonlinear finite element models of RCB are developed in ANSYS. A series of pushover analyses are then performed to obtain the pushover curves of RCB. Different capacity curves are compared to recognize the influence of different material models on the nonlinear behavior of RCB. Additionally, the effects of prestressing forces on the seismic performances of the structure are also investigated. Moreover, a set of damage states corresponding to damage evolutions of the structures is proposed in this study.

Purpose: This study describes the creation of patient-specific (PS) osteo-ligamentous finite element (FE) models of the spine, ribcage, and pelvis, simulation of up to three years of region-specific, stress-modulated growth, and validation of simulated curve progression with patient clinical angle measurements. Research Question:Does the inclusion of region-specific, stress-modulated vertebral growth, in addition to scaling based on age, weight, skeletal maturity, and spine flexibility allow for clinically accurate scoliotic curve progression prediction in patient-specific FE models of the spine, ribcage, and pelvis? Methods: Frontal, lateral, and lateral bending X-Rays of five AIS patients were obtained for approximately three-year timespans. PS-FE models were generated by morphing a normative template FE model with landmark points obtained from patient X-rays at the initial X-ray timepoint. Vertebral growth behavior and response to stress, as well as model material properties were made patient-specific based on several prognostic factors. Spine curvature angles from the PS–FE models were compared to the corresponding X-ray measurements. Results: Average FE model errors were 6.3 ± 4.6°, 12.2 ± 6.6°, 8.9 ± 7.7°, and 5.3 ± 3.4° for thoracic Cobb, lumbar Cobb, kyphosis, and lordosis angles, respectively. Average error in prediction of vertebral wedging at the apex and adjacent levels was 3.2 ± 2.2°. Vertebral column stress ranged from 0.11 MPa in tension to 0.79 MPa in compression. Conclusion: Integration of region-specific stress-modulated growth, as well as adjustment of growth and material properties based on patient-specific data yielded clinically useful prediction accuracy while maintaining physiological stress magnitudes. This framework can be further developed for PS surgical simulation.

Purpose: To assess the complication risks associated with intrathecal baclofen (ITB) pumps in cerebral palsy (CP) patients undergoing posterior spinal fusion (PSF) and to determine if timing of pump implantation before or during PSF impacts the risk of complications. Methods: A prospectively collected multicenter database was retrospectively reviewed to identify CP patients undergoing PSF from 2008 to 2023. Patients were divided into 2 cohorts: those with an ITB pump (ITB cohort) and those without (non-ITB cohort). The ITB cohort was further categorized by placement of the pump prior to or during PSF. Cohorts were then compared in terms of postoperative complications, perioperative complications, and need for revision surgery. Results: Four hundred six patients (ITB n= 79 [53 prior to, 26 during PSF], non-ITB n= 326) were included in this analysis. At an average follow-up of 4.0 years (range 2–10 years), there were no significant differences between the ITB and non-ITB cohorts in the rate of perioperative complications (5.0% vs 6.5%, p= 0.80), revision surgeries (2.5% vs 4.6%, p= 0.54), or any complication type, regardless of whether pumps were placed prior to or during PSF, aside from longer surgical times in the latter group. Conclusion: Complication rates are similar for ITBs placed prior to and during PSF. Patients with spastic CP may safely be treated with ITB pumps without increased risks of complication or further reoperation/revision following PSF. Level of evidence: Level III.

Purpose: Given the challenges associated with managing progressive scoliosis in patients with cerebral palsy (CP), the purpose of this study was to evaluate deformity correction and HRQOL 5 years post-spinal fusion in CP patients who were skeletally immature at the time of surgical correction. Methods: CP patients who underwent definitive fusion before age 11 with minimum 5-years follow-up from a prospective, multicenter registry were included. Preoperative, initial postoperative, and 5-years radiographic data were collected. Preoperative and 5-years demographic, surgical data, complications, and CPCHILD outcome scores were analyzed. Repeated measures ANOVA with Bonferroni adjustment were used to analyze radiographic measures. Paired ttest was utilized to compare outcomes. Significance was set at p= 0.05. Results: Twenty patients met inclusion—17 females, 3 males. The mean age was 9 (range 8–10) years. Eight-five percent had spastic CP with GMFCS Level V. Eighteen patients underwent posterior fusion; distal fixation was to the ilium in 80% and to L4-S1 in 20%. Significant correction of the primary curve (p≤ 0.001) and pelvic obliquity (p≤ 0.001) were obtained. From initial postoperative to 5-years follow-up there were no significant changes in major curve magnitude (p= 0.638), thoracic kyphosis (p= 0.09) or pelvic obliquity (p= 0.28). CPCHILD personal care, mobility, comfort, and total scores improved from preoperative to 5-years (p&lt; 0.05). One patient needed a reoperation. Conclusion: Surgical decision making for scoliosis in patients with CP can be difficult given the desire to maximize growth while minimizing adverse events. Performing a definitive fusion is a viable option that achieves good correction which remains stable 5 years postoperatively.

AbstractRho-associated, coiled-coil-containing protein kinase (ROCK1) regulates cell contraction, morphology, and motility by phosphorylating its downstream targets. ROCK1 is a proven target for many pathological conditions like cancer, atherosclerosis, glaucoma, neuro-degeneration, etc. Though many kinase inhibitors are available, there is a dearth of studies on repurposing approved drugs and novel peptide inhibitors that could potentially target ROCK1. Hence, in this study, an extensive integration of open-source pipelines was employed to probe the potential inhibitors (ligand/peptide) for targeting ROCK1. To start with, a systematic enrichment analysis was performed to delineate the most optimal ROCK1 crystal structure that can be harnessed for drug design. A comparative analysis of conformational flexibility between monomeric and dimeric forms was also performed to prioritize the optimal assembly for structural studies. Subsequently, Virtual screening of FDA-approved drugs in Drugbank was performed using POAP pipeline. Further, the top hits were probed for binding affinity, crucial interaction fingerprints, and complex stability during MD simulation. In parallel, a combinatorial tetrapeptide library was also virtually screened against ROCK1 using the PepVis pipeline. Following which, all these shortlisted inhibitors (compounds/peptides) were subjected to Kinomerun analysis to infer other potential kinase targets. Finally, Polydatin and conivaptan were prioritized as the most potential repurposable inhibitors, and WWWF, WWVW as potential inhibitory peptides for targeting ROCK1. The prioritized inhibitors are highly promising for use in therapeutics, as these are resultants of the multilevel stringent filtration process. The computational strategies implemented in this study could potentially serve as a scaffold towards selective inhibitor design for other kinases.Communicated by Ramaswamy H. Sarma

Tm2O3doped tellurite glasses ((64.9-x)TeO2+15ZnO+10Bi2O3+10WO3+0.1Er2O3+xTm2O3) were prepared using the conventional melt-and-quench system. The tellurite glass samples, doped with varying concentrations of Tm2O3(x = 0 (TZBWET1), 0.4 (TZBWET2), 0.8 (TZBWET3), and 1.0 (TZBWET4) mol%) were studied for their ability to absorb gamma radiation. The mass attenuation coefficients (MACs) of the glasses were computed for gamma photons beams having energies E within the range 0.015 ≤ E ≤ 15 MeV using the popular and accurate NIST-XCOM database. The density of TZBWET1, TZBWET2, TZBWET3, and TZBWET4 is 6.006 g/cm3, 6.141 g/cm3, 6.259 g/cm3, and 6.308 g/cm3, respectively. The mass attenuation coefficients varied within the range 0.036–57.990 cm2/g, 0.036–58.233 cm2/g, 0.036–58.475 cm2/g, and 0.036–58.597 cm2/g for TZBWET1, TZBWET2, TZBWET3, and TZBWET4, respectively. The corresponding linear attenuation coefficients are within 0.236–348.290 cm−1, 0.241–357.607 cm−1, 0.246–365.994 cm−1, and 0.248–369.623 cm−1, respectively. The shielding potential of the glasses improved with the addition of Tm2O3. The TZBWET glasses showed better shielding potential with respect to commercial shielding glasses and thus are environmentally friendly alternative to available Pb-rich commercial glass shields. The study provided valuable insights into the potential use of Tm2O3doped tellurite glass as a promising material for radiation shielding applications, particularly in nuclear power, medical imaging, and industrial radiography.

Background: Accurate reporting of long-term complications of surgical treatment of adolescent idiopathic scoliosis (AIS) is critical, but incomplete. This study aimed to report on the rate of complications following surgical treatment of AIS among patients with at least 10 years of follow-up. Methods: This was a retrospective review of prospectively collected data from a multicenter registry of patients who underwent surgical treatment for AIS with minimum 10-year follow-up. Previously published complications were defined as major if they resulted in reoperation, prolonged hospital stay/readmission, neurological deficits, or were considered life-threatening. Rates and causes of reoperations were also reviewed. Results: Two hundred and eighty-two patients were identified with mean age at surgery of 14.6 ± 2.1 years. Mean follow-up was 10.6 (range 9.5–14) years. Eighty-seven patients had anterior spinal fusion (ASF); 195 had posterior spinal fusion (PSF). The overall major complication rate was 9.9% (n= 28) in 27 patients. Among PSF patients, the complication rate was 9.7% (n= 19) in 18 patients. The complications were surgical site infection (37%), adding-on (26%), pulmonary (16%), neurologic (11%), instrumentation (5%), and gastrointestinal (5%). In ASF patients, the complication rate was 10.3% (n= 9) among nine patients. The complications were pulmonary (44%), pseudoarthrosis (22%), neurologic (11%), adding-on (11%), and gastrointestinal (11%). The reoperation rate was 6.0% (n= 17) among 17 patients. Although most of the complications presented within the first 2 years (60.7%), surgical site infection and adding-on were also seen late into the 10-year period. Conclusion: This is the largest prospective study with at least a 10-year follow-up of complications following spinal fusion for AIS, the overall major complication rate was 9.9% with a reoperation rate of 6.0%. Complications presented throughout the 10-year period, making long-term follow-up very important for surveillance. Level of evidence: Therapeutic II.

Purpose: Vertebral body tethering (VBT) continues to grow in interest from both a patient and surgeon perspective for the treatment of scoliosis. However, the data are limited when it comes to surgeon selection of both procedure type and instrumented levels. This study sought to assess surgeon variability in treatment recommendation and level selection for VBT versus posterior spinal fusion (PSF) for the management of scoliosis. Methods: Surgeon members of the Pediatric Spine Study Group and Harms Study Group were queried for treatment recommendations and proposed upper instrumented vertebra (UIV) and lower instrumented vertebra (LIV) selection for PSF and VBT based on 17 detailed clinical vignettes. Responses were subdivided in each clinical vignette according to surgeon experience and treatment recommendations with assessment of intra-rater reliability. Binomial distribution tests were used to establish equipoise, selecting p&lt; 0.10 to indicate the presence of a treatment choice with consensus set > 70% agreement. For treatment choice, responses were assessed first for consensus on the decision to proceed with PSF or VBT. Results: Thirty-five surgeons with varied experience completed the survey with 26 surgeons (74%) completing the second follow-up survey. Overall, VBT was the recommended treatment by 47% of surgeons, ranging by clinical vignette. Consensus in treatment recommendation was present for 6 clinical vignettes including 3 for VBT and 3 for PSF, with equipoise present for the remaining 11. Of the 17 vignettes, 12 demonstrated moderate intra-observer reliability including the 3 consensus vignettes for VBT. Sanders stage ≤ 3 and smaller curve magnitude were related with VBT recommendation but neither age nor curve flexibility significantly influenced the decision to recommend VBT. Surgeons with high VBT volume, ≥ 11 VBT cases/year, were more likely to recommend VBT than those with low volumes (0–10 cases per year (p&lt; 0.0001)). High VBT volume surgeons demonstrated consensus in VBT recommendation for Lenke 5/6 curves (75% mean recommendation). High VBT volume surgeons had a significantly higher VBT recommendation rate for Lenke 1A, 2A curves (71.8% vs 48.0%, p= 0.012), and Lenke 3 curves (62% vs 26.9%, p= 0.023). Equipoise was present for all vignettes in low volume surgeons. In addition, high VBT volume surgeons trended toward including more instrumented levels than low VBT volume surgeons (7.17 vs 6.69 levels). Conclusion: Significant equipoise is present among pediatric spine surgeons for treatment recommendations regarding VBT and PSF. Surgeon-, patient-, and curve-specific variables were identified to influence treatment recommendations, including surgeon experience, curve subtype, deformity magnitude, and skeletal maturity. This study highlights the need for continued research in identifying the optimal indications for VBT and PSF in the treatment of pediatric spinal deformity.

Purpose: Pulmonary function and quality of life (QOL) are important outcome measures for patients with early-onset scoliosis (EOS) undergoing rib-based growing system (RBGS) implantation. The Assisted Ventilation Rating (AVR) measures ventilator requirements in this population. A higher, more severe, score implies negative changes in QOL. The EOS Questionnaire (EOSQ) is a validated outcome measure. Paired measurements for both ratings were compared to clarify correlation between ventilator status and QOL. Secondary analysis aimed at defining QOL between more broad subgroups defined by ventilator use. Methods: AVR and EOSQ scores were extracted from the Pediatric Spine Study Group database for patients 10 years of age and under. Instances were excluded if the time between AVR and EOSQ assessment was greater than 6 months. Scores were compared using Spearman correlation coefficient. Subgroup analysis included control for age, gender, and etiology. Secondary analysis was performed for broad functional grouping using ranked analysis of variance for repeated measures using median scores. Results: Two thousand five hundred and forty-two instances of paired EOSQ and AVR in 329 patients were analyzed. A statistically significant weak correlation between AVR and EOSQ was identified in Child’s Health Related QOL and Family Impact sections, in nine subsets. Subgroup analysis showed little variation, except increased correlation in female patients to near moderate level. Analysis of variance for demonstrated decreased medians for all subdomains when comparing those mechanically ventilated to patients who did not require ventilation. Conclusion: Ventilator status tracks with QOL were measured by EOSQ. A more severe AVR is negatively correlated with most domains of the EOSQ for patients with EOS who have undergone RBGS implantation. The strength of this correlation is weak, and so AVR alone may be insufficient to precisely determine QOL in this population. Level of evidence: Level-III, Retrospective.

Purpose: To establish expert consensus on various parameters that constitute elevated risk during spinal deformity surgery and potential preventative strategies that may minimize the risk of intraoperative neuromonitoring (IONM) events and postoperative neurological deficits. Methods: Through a series of surveys and a final virtual consensus meeting, the Delphi method was utilized to establish consensus among a group of expert spinal deformity surgeons. During iterative rounds of voting, participants were asked to express their agreement (strongly agree, agree, disagree, strongly disagree) to include items in a final set of guidelines. Consensus was defined as ≥ 80% agreement among participants. Near-consensus was ≥ 60% but &lt; 80% agreement, equipoise was ≥ 20% but &lt; 60%, and consensus to exclude was &lt; 20%. Results: Fifteen of the 15 (100%) invited expert spinal deformity surgeons agreed to participate. There was consensus to include 22 determinants of high-risk (8 patient factors, 8 curve and spinal cord factors, and 6 surgical factors) and 21 preventative strategies (4 preoperative, 14 intraoperative, and 3 postoperative) in the final set of best practice guidelines. Conclusion: A resource highlighting several salient clinical factors found in high-risk spinal deformity patients as well as strategies to prevent neurological events was successfully created through expert consensus. This is intended to serve as a reference for surgeons and other clinicians involved in the care of spinal deformity patients. Level of evidence: Level V.

Optical coherence tomography angiography (OCTA) is a non-invasive tool to assess the retino-choroidal vasculature in vivo. It tracks the red blood cell movement and maps the vasculature in quick succession. In routine, diabetic retinopathy, age related macular degeneration, central serous chorioretinopathy, and others are commonly being studied to unveil its clinic role. On the other hand, amblyopia is a condition where the visual acuity is subnormal due to non-organic causes in the eye. But the OCTA studies till now have shown variable changes along retino-choroidal vasculature. Hence, to comprehend the existing literature knowledge, a systematic literature search was carried out and the original works describing novel findings in amblyopic eyes on OCTA were included. Upon detailed assessment, firstly, the disturbed vasculature along superficial retinal plexus, deeper retinal plexus, and choroidal plexus were evident in most untreated amblyopic eyes. However, such changes were not uniform, which is due to noted heterogenic patient profile, small sample size, biometric biases, non-uniform algorithms, and other factors. And to note, even in presence of such diverse changes, almost all the authors stated a plausible explanation for their notable changes. Secondly, the utility of OCTA in identifying vascular changes with standard treatments and segregation of visual beneficiaries from non-beneficiaries were possible. Hence, to conclude, OCTA is a valuable tool which can provide valuable useful insights into the amblyopic eyes during pre and post treatment periods. However, to gather more concrete evidence for clinical benefits, systematic, homogenous, and better structured clinical studies are mandated.

Study design: Prospective multicenter international observational study. Objective: To investigate the effect of implant density on clinical outcomes in complex pediatric spine reconstruction. Summary of background data: Implant density in spine deformity surgery has been a subject of much debate with some authors advocating higher density for better correction. Few studies have looked at the effect of implant density on severe curves > 100 deg or treated with vertebral column resection (VCR). Methods: 250/311 pts with 2-year f/u enrolled in the FOX pediatric database from 17 international sites were queried for the impact of implant density and surgical outcomes. Patients were grouped into three implant density categories for comparative analysis Group 1 (density ≤ 1), Group 2 (1 &lt; density &lt; 1.5) and Group 3 (density; 1.5–2). Results: 250 pts: 47 (Grp1)/99 (Grp2) /104 (Grp3); Pre-op age and etiology and curve types were similar in all groups, but body mass index (BMI) was higher in Grp3. Grps 1 and 2 had significantly higher sagittal deformity angular ratio (S-DAR) compared to Grp 3 (p&lt; 0.001). Pre-op Halo Gravity Traction (HGT) was used in 55.3%/44.4%/31.7%, p= 0.017; Grp1/Grp2/Grp3, respectively. Average duration of surgery (min) was higher in Grp3 relative to Grp1 only: 352.5/456.5/515.0, p= 0.0029. Blood loss was similar in all Grps. Rate of VCR, PSO and SPO was similar in all Grps. Pre-op Coronal Cobb avg 96.1/83.6/88.6, p= 0.2342, attained similar correction after HGT (24.6%/27.2%/23.2%, p= 0.4864. Coronal Cobb corrections at 2-year follow-up (FU) were (37.1%/40.3%/53.5%, p= 0.0004). Pre-op sagittal Cobb was (105.4/101.9/75.9, p&lt; 0.01.), achieved similar %correction in HGT (19.1%/22.3%/22.5%, p= 0.6851) and at 2-year FU (39.6%/41.4%/29.8%, p= 0.1916). After adjusting for C-DAR, S-DAR, pre-op coronal and sagittal Cobb, etiology, curve types, age, BMI and number of rods in multivariate analysis, the odds of developing post-operative implant complication was 11 times greater in group 1 compared to group 3 (OR = 11.17,95% CI 2.34–53.32). There was significant improvement in SRS scores in all Grps at 2-year FU. Conclusion: Although higher implant density was observed to be associated with greater curve correction and lower rates of post-operative implant-related complication and revision in heterogeneous case groups, the results may not imply causality of implant density on the outcomes in severe pediatric spine reconstruction.

Purpose: Since the introduction of vertebral body tethering (VBT) for adolescent idiopathic scoliosis (AIS), a variety of post-operative chest drainage systems have been utilized. Most surgeons use formal chest tubes with a Pleur-evac, while others use smaller bulb suction drains (e.g., Blake drain). In addition, some centers utilize pleural closure. This multicenter study evaluates whether drain type or pleural closure impact perioperative and 90 day complication rates. Methods: A retrospective review was conducted from three institutions with established VBT programs. All preoperative, perioperative and 90 day postoperative data were analyzed to determine differences in outcomes between three cohorts: standard chest tube (SCT), standard chest tube with pleural closure (SCTPC) and 10 French Bulb drain (BD). Results: 104 patients were identified for the study. 57 SCT, 25 SCTPC and 22 BD. All data are listed in order: SCT, SCTPC, BD. Length of stay (3.7, 4.3, 3.0 days) was less in the BD group (p= 0.009); post-operative drainage (460, 761, 485 cc) was less in the SCT and BD groups (p&lt; 0.001); intra-operative estimated blood loss (EBL) 146, 382, 64 cc was less in the BD group (p&lt; 0.001). No significant difference in number of days (3.2, 3.2, and 2.8 days) drainage was in place, groups (p= 0.311). Complication profile was similar with 2 chest tube reinsertions in the SCT and one hemothorax that resolved spontaneously in BD group. Conclusions: In this series of 104 patients, SCT, SCTPC and BD all had a similar safety profile. All three methods were safe and effective in managing post-operative chest drainage after thoracic VBT. In the series, BD group had significantly shorter LOS than both groups that used chest tubes. Level of evidence: Level III, Retrospective cohort study.

Purpose: Prior work identified optimal outcomes at 2 years following selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS) but it is unclear whether these published predictors represent what is required to achieve an optimal outcome with further time and potential growth. The purpose of this study was to determine the preoperative factors associated with optimal outcome of STF for AIS at 5 years. Methods: Patients with primary thoracic AIS (Lenke 1–4C curves) who underwent a STF and had minimum 5 years of follow-up were included. Optimal postoperative outcomes for a STF included a deformity-flexibility quotient (DFQ) &lt; 4, lumbar curve &lt; 26°, lumbar correction > 37%, C7-CSVL &lt; 2 cm, lumbar prominence &lt; 5°, and trunk shift &lt; 1.5 cm. These outcomes were used to determine whether adhering to published recommendations for STF increased the likelihood of obtaining an optimal outcome at 5 years, which included: preoperative lumbar curve &lt; 45°, lumbar bend &lt; 25°, apical vertebral translation ratio > 1.2, and thoracic/thoracolumbar Cobb ratio > 1.2. Results: 127 patients met inclusion. A preoperative lumbar curve &lt; 45° was associated with an increased likelihood of achieving three of the optimal outcomes: DFQ &lt; 4, lumbar curve &lt; 26°, and lumbar prominence &lt; 5°. Following the 25° bend rule resulted in two optimal outcomes, while Cobb ratio > 1.2 was only associated with one optimal outcome. AVT > 1.2 was not significantly associated with any optimal outcome measures. Conclusion: This study found that at 5 years, performing a STF when there is a preoperative lumbar Cobb &lt; 45° remained the best guideline for increasing the likelihood of an optimal outcome.

Purpose: To expand on previously described intraoperative aids by developing consensus-based best practice guidelines to optimize the approach to intraoperative neuromonitoring (IONM) events associated with “high-risk” spinal deformity surgery. Methods: Consensus was established among a group of experienced spinal deformity surgeons by way of the Delphi method. Through a series of iterative surveys and a final virtual consensus meeting, participants expressed their agreement (strongly agree, agree, disagree, and strongly disagree) with various items. Consensus was defined as ≥ 80% agreement (“strongly agree” or “agree”). Near-consensus was defined as ≥ 60% but &lt; 80%. Equipoise was ≥ 20% but &lt; 60%, and consensus to exclude was &lt; 20%. Results: 15 out of 15 (100%) invited surgeons agreed to participate. Final consensus supported inclusion of 105 items (53 in Response Algorithm, 13 in Ongoing Consideration of Etiology, 31 in Real-Time Data Scenarios, 8 in Patterns of IONM Loss), which were organized into a final set of best practice guidelines. Conclusion: Detailed consensus-based best practice guidelines and aids were successfully created with the intention to help organize and direct the surgical team in exploring and responding to neurological complications during high-risk spinal deformity surgery. Level of evidence: Level V.

This study identifies efficient earthquake intensity measures (IMs) for seismic performances and fragility evaluations of the reactor containment building (RCB) in the advanced power reactor 1400 (APR1400) nuclear power plant (NPP). The computational model of RCB is constructed using the beam-truss model (BTM) for nonlinear analyses. A total of 90 ground motion records and 20 different IMs are employed for numerical analyses. A series of nonlinear time-history analyses are performed to monitor maximum floor displacements and accelerations of RCB. Then, probabilistic seismic demand models of RCB are developed for each IM. Statistical parameters including coefficient of determination (R2), dispersion (i.e. standard deviation), practicality, and proficiency are calculated to recognize strongly correlated IMs with the seismic performance of the NPP structure. The numerical results show that the optimal IMs are spectral acceleration, spectral velocity, spectral displacement at the fundamental period, acceleration spectrum intensity, effective peak acceleration, peak ground acceleration, A95, and sustained maximum acceleration. Moreover, weakly related IMs to the seismic performance of RCB are peak ground displacement, root-mean-square of displacement, specific energy density, root-mean-square of velocity, peak ground velocity, Housner intensity, velocity spectrum intensity, and sustained maximum velocity. Finally, a set of fragility curves of RCB are developed for optimal IMs.

The revolutionary technology of 3D printing has gained traction in the medical field in recent years; spine surgery has in particular seen major advances in 3D printing. The applications of this technology have grown from utilizing 3D models to enhance patient education to patient specific, highly detailed intraoperative anatomical molds. However, obstacles remain that prevent the widespread utilization of 3D printing in spine surgery such as cost, time consumption, lack of long-term data, and regulation by the US FDA. Despite these obstacles, it is evident that 3D printing will be utilized to optimize preoperative, intraoperative, and postoperative care of patients with spine deformity. The purpose of this review is to establish the applications of 3D printing for spine surgery.

Study design: Retrospective, multicenter comparative. Objectives: Our purpose was to compare early onset scoliosis (EOS) patients treated with ultra-low, low, and high implant density constructs when undergoing conversion to definitive fusion. Summary of background data: Larson et al.demonstrated that implant density (ID) at fusion does not correlate with outcomes in the treatment of adolescent idiopathic scoliosis, but did not address growth-friendly graduates. Methods: EOS patients treated with growth-friendly constructs converted to fusion between 2000 and 2017 were reviewed from a multicenter database. ID was defined as number of pedicle screws, hooks, and sublaminar/bands per level fused. Patients were divided into ultra-low ID (&lt; 1.3), low (≥ 1.3 and &lt; 1.6), and high ID (≥ 1.6). Exclusion criteria: &lt; 2 years follow-up from fusion or inadequate radiographs. Results: A total of 152 patients met inclusion criteria with 39 (26%) patients in the high ID group, 33 (22%) patients in the low ID group, and 80 (52%) in the ultra-low ID group. Groups were similar in operative time (p= 0.61), pre-fusion major curve (p= 0.71), mean number of levels fused (p= 0.58), clinical follow-up (p= 0.30), and radiographic follow-up (p= 0.90). Patients in the low ID group (11.6 ± 1.5 years) were slightly younger at the time of definitive fusion than patients in the ultra-low ID group (12.9 ± 2.2 years) and high ID group (12.5 ± 1.7 years) (p= 0.009). There was significantly more blood loss in the high ID group than the other two groups (high ID: 946.8 ± 606.0 mL vs. low ID: 733.9 ± 434.5 mL and ultra-low ID: 617.4 ± 517.2 mL; p= 0.01), but there was no significant difference with regard to percent of total blood volume lost (high ID: 59.3 ± 48.7% vs. low ID: 54.5 ± 37.5% vs. ultra-low ID: 51.7 ± 54.9%; p= 0.78). There was a difference in initial improvement in major curve between the groups (high ID: 21.6° vs. low ID: 18.0° vs. ultra-low ID: 12.6°; p= 0.01). However, during post-fusion follow-up, correction decreased 7.1° in the high ID group, 2.6 in the low ID group, and 2.8 in the ultra-low ID group (p= 0.19). At final follow-up, major curve correction from pre-fusion was similar between groups (high ID: 14.5° vs. low ID: 15.5° vs. ultra-low ID: 9.7°, p= 0.14). At final follow-up, there was no difference in T1–T12 length gain (p= 0.85), T1–S1 length gain (p= 0.68), coronal balance (p= 0.56), or sagittal balance (p= 0.71). The revision rate was significantly higher in the ultra-low ID group (13.8%; 11/80) versus the high ID group (2/39; 5.1%) and low ID group (0/33; 0%) (p= 0.04). Conclusions: Although an ID &lt; 1.3 in growth-friendly graduates produces similar outcomes with regard to curve correction and spinal length gain as low and high ID, this study suggests that an ID &lt; 1.3 is associated with an increased revision rate. Level of evidence: III.

Study design: Retrospective review of a prospectively collected multicenter database. Objectives: To identify risk factors for early and late readmission of surgically treated patients with adolescent idiopathic scoliosis (AIS). Summary of background data: Specific risk factors associated with readmission in patients with AIS remain poorly understood. Methods: Patients with AIS who were operatively treated from 19 centers specializing in the treatment of pediatric spinal deformity were studied. Data from a minimum 2 years of clinical follow-up and any readmission were available for analysis. Characteristics of patients with no readmission, early readmission (&lt; 90 days), and late readmission (> 90 days) were evaluated. Both univariate and multivariate analyses of risk factors for readmission were performed. Results: 2049 patients were included in our cohort, with 1.6% requiring early readmission and 3.3% late readmission. In the multivariate analysis, greater preoperative coronal imbalance was associated with early readmission. Longer operative time was associated with late readmission. Finally, greater preoperative pain (SRS-22 pain scale) was associated with both early and late readmission. GI complications accounted for a higher proportion of early readmissions than previously reported in the literature. Conclusions: Preoperative counseling of patients with higher levels of pain and coronal imbalance and the implementation of a thorough postoperative bowel regimen may help optimize patient outcomes. Level of evidence: 3.

Supporters of the opposition staged nothing short of a civilian coup against the Pakistani military. [ABSTRACT FROM AUTHOR]

Sagittal alignment abnormalities in Scheuermann kyphosis (SK) strongly correlate with quality of life measures. The changes in spinopelvic parameters after posterior spinal fusion have not been adequately studied. This study is to evaluate the reciprocal changes in spinopelvic parameters following surgical correction for SK.