Search

Background Context: We developed the New England Spinal Metastasis Score (NESMS) as a simple, informative, scoring scheme that could be applied to both operative and non-operative patients. The performance of the NESMS to other legacy scoring systems has not previously been compared using appropriately powered, prospectively collected, longitudinal data.Purpose: To compare the predictive capacity of the NESMS to the Tokuhashi, Tomita and Spinal Instability Neoplastic Score (SINS) in a prospective cohort, where all scores were assigned at the time of baseline enrollment.Patient Sample: We enrolled 202 patients with spinal metastases who met inclusion criteria between 2017-2019.Outcome Measures: One-year survival (primary); 3-month mortality and ambulatory function at 3- and 6-months were considered secondarily.Methods: All prognostic scores were assigned based on enrollment data, which was also assigned as time-zero. Patients were followed until death or survival at 365 days after enrollment. Survival was assessed using Kaplan-Meier curves and score performance was determined via logistic regression testing and observed to expected plots. The discriminative capacity (c-statistic) of the scoring measures were compared via the z-score.Results: When comparing the discriminative capacity of the predictive scores, the NESMS had the highest c-statistic (0.79), followed by the Tomita (0.69), the Tokuhashi (0.67) and the SINS (0.54). The discriminative capacity of the NESMS was significantly greater (p-value range: 0.02 to <0.001) than any of the other predictive tools. The NESMS was also able to inform independent ambulatory function at 3- and 6-months, a function that was only uniformly replicated by the Tokuhashi score.Conclusions: The results of this prospective validation study indicate that the NESMS was able to differentiate survival to a significantly higher degree than the Tokuhashi, Tomita and SINS. We believe that these findings endorse the utilization of the NESMS as a prognostic tool capable of informing care for patients with spinal metastases. [ABSTRACT FROM AUTHOR]

Background Context: The New England Spinal Metastasis Score (NESMS) was proposed as an intuitive and accessible prognostic tool for predicting survival in patients with spinal metastases. We designed an appropriately powered, prospective, longitudinal investigation to validate the NESMS.Purpose: To prospectively validate the NESMS.Study Design: Prospective longitudinal observational cohort study.Patient Sample: Patients, aged 18 and older, presenting for treatment with spinal metastatic disease.Outcome Measures: One-year mortality (primary); 6-month mortality and mortality at any time point following enrollment (secondary).Methods: The date of enrollment was set as time zero for all patients. The NESMS was assigned based on data collected at the time of enrollment. Patients were prospectively followed to one of two predetermined end-points: death, or survival at 365 days following enrollment. Survival was visually assessed with Kaplan-Meier curves and then analyzed using multivariable logistic regression, followed by Bayesian regression to assess for robustness of point estimates and 95% confidence intervals (CI).Results: This study included 180 patients enrolled between 2017 and 2018. Mortality within 1-year occurred in 56% of the cohort. Using NESMS 3 as the referent, those with a score of 2 had significantly greater odds of mortality (odds ratio 7.04; 95% CI 2.47, 20.08), as did those with a score of 1 (odds ratio 31.30; 95% CI 8.82, 111.04). A NESMS score of 0 was associated with perfect prediction, as 100% of individuals with this score were deceased at 1-year. Similar determinations were encountered for mortality at 6-months and overall.Conclusions: This study validates the NESMS and demonstrates its utility in prognosticating survival for patients with spinal metastatic disease, irrespective of selected treatment strategy. This is the first study to prospectively validate a prognostic utility for patients with spinal metastases. The NESMS can be directly applied to patient care, hospital-based practice and health-care policy. [ABSTRACT FROM AUTHOR]

Background Context: Laboratory values have been found to be useful predictive measures of survival following surgery. The utility of laboratory values for prognosticating outcomes among patients with spinal metastases has not been studied.Purpose: To determine the prognostic capacity of laboratory values at presentation including white blood cell count, serum albumin and platelet-lymphocyte ratio (PLR) in patients with spinal metastases.Study Design: Retrospective review of records from two tertiary care centers (2005-2017).Patient Sample: Patients, aged 40 to 80, who received operative or nonoperative management for spinal metastases.Outcome Measures: Survival, complications, or hospital readmissions within 90 days of treatment and a composite measure for treatment failure accounting for changes in ambulatory function and mortality at 6 months following presentation.Methods: Multivariable Cox proportional hazard regression analysis was used to analyze the relationship between laboratory values and length of survival, adjusting for confounders. Multivariable logistic regression was used in analyses related to 6-month and 1-year mortality, complications, readmissions, and treatment failure. A scoring rubric was developed based on the performance of laboratory values in the multivariable tests. Internal validation was performed using a bootstrap simulation that consisted of sampling with replacement and 1,000 replications.Results: We included 1,216 patients. Thirty-seven percent of patients received a surgical intervention and 63% were treated nonoperatively. Median survival for the cohort as a whole was 255 days (interquartile range 93-642 days). The PLR (hazard ratio [HR] 1.53; 95% confidence interval [CI] 1.29, 1.80; p<.001) and albumin (HR 0.54; 95% CI 0.45, 0.64; p<.001) were significantly associated with survival, whereas WBC count (HR 1.08; 95% CI 0.86, 1.36; p=.50) was not associated with this outcome. Similar findings were encountered for 6-month and 1-year mortality as well as the composite measure for treatment failure. The PLR and albumin performed well in our scoring rubric and findings were preserved in the bootstrapping validation.Conclusions: Individuals with low serum albumin and elevated PLR should be advised regarding the impact of these laboratory markers on outcomes including survival, irrespective of treatments received. An effort should also be made to optimize nutrition and PLR, if practicable, before treatment to minimize the potential for development of adverse events. [ABSTRACT FROM AUTHOR]

Background Context: Emerging literature has identified the importance of pretreatment health and functional status as influential in the prognostication of survival. A comprehensive, accessible, predictive model for survival following cervical spine fracture has yet to be developed.Purpose: To develop an accessible and intuitive predictive model for survival in individuals aged 50 and older treated for cervical spine fractures.Study Design: Retrospective review of records from two tertiary care centers (2009-2016).Patient Sample: Patients age 50 and older who received operative or nonoperative management for cervical fractures.Outcome Measures: One-year mortality was the primary outcome with 3-month and 2-year mortality considered secondarily.Methods: Multivariable logistic regression was used to identify factors independently associated with mortality. The magnitude and precision of the relationship with 1-year mortality for statistically significant variables determined weighting in the scoring system subsequently developed. Score performance was tested through multivariable regression and bootstrap simulation. In a sensitivity test, the performance of the score developed for 1-year mortality was assessed using figures for the 3-month and 2-year time-points.Results: We included 1,758 patients. Mortality rates were 12% at 3 months, 17% at 1 year, and 21% at 2 years. Following multivariable testing age, injury severity score and Glasgow coma scale demonstrated the strongest predictive values for a base score, followed by serum albumin and ambulatory status. The resultant composite score ranged from 0 (base score≤4, albumin≤3.5 g/dL, and dependent/nonambulator at presentation) to a maximum of 4 (base score≥5, albumin>3.5 g/dL, and independent ambulator at presentation). Following multivariable analysis, when compared to patients with a score of 4, significantly increased odds of 1-year mortality were appreciated for those with scores of 3 (odds ratio [OR] 7.35; 95% confidence interval [CI] 3.77, 14.32), 2 (OR 8.43; 95% CI 4.66, 15.25), 1 (OR 17.47; 95% CI 9.81, 31.11), and 0 (OR 26.58; 95% CI 13.87, 50.92). Score performance was unchanged in bootstrap testing and sensitivity analyses.Conclusions: We have developed a useful prognostic utility capable of informing survival in individuals age 50 and older, following cervical spine fractures. The score can be applied to adjust patient expectations, anticipate outcomes, and as an adjunct to decision-making in the postinjury period. [ABSTRACT FROM AUTHOR]

Background The main reconstruction techniques for proximal humerus tumors include osteoarticular allografts (OAs), endoprostheses (EPs), or allograft prosthetic composites (APCs). A common complication is infection, and constructs involving the use of allografts are believed to be at a higher risk of infection. Literature comparing infection rates between different modalities of reconstruction is scarce and underpowered. The study purposes were (1) to determine and compare the prevalence of infection in patients who underwent reconstruction of the proximal humerus including OAs, EPs, and APCs; (2) to identify preoperative, perioperative, and postoperative predictors of infection that might be modifiable; and (3) to present our protocol of treatment in patients with superficial and deep infections. Methods We reviewed 150 patients of all ages with proximal humerus tumors treated by an OA, EP, or APC at 2 tertiary institutions. The prevalence of infection for each modality was calculated and compared between groups. We identified potential predictors of infection with stepwise backward multivariate Cox regression analysis. Results An infection developed in 19 patients (12%): 5 of 45 (11%) in the OA group, 12 of 85 (14%) in the EP group, and 2 of 20 (10%) in the APC group ( P  = .740). A lower preoperative hemoglobin blood level and low preoperative albumin blood level were independently associated with infection. Conclusions We found similar infection rates compared with previously reported series. However, we did not identify a higher infection prevalence in constructs using allografts. Patients with a lower preoperative hemoglobin or albumin level are at higher risk of infection and should undergo optimization before surgery. [ABSTRACT FROM AUTHOR]

Background Knowledge of surgical outcome and its predictors helps inform patients and aids in surgical decision-making. We aimed to assess the outcome—reoperation and systemic complication rate—of surgery for humeral metastases, myeloma, or lymphoma. Our null hypothesis was that there are no factors associated with these outcomes. Methods We included 295 consecutive patients in this retrospective study: 134 (45%) proximal, 131 (44%) diaphyseal, and 30 (10%) distal impending or pathologic fractures. Proximal lesions were treated by intramedullary nailing (43%, n = 57), prosthesis (34%, n = 46), plate-screw fixation (22%, n = 30), and a combination (n = 1). Diaphyseal lesions were treated by intramedullary nailing (69%, n = 91), plate-screw fixation (30%, n = 39), and a combination (n = 1). Distal lesions were treated by plate-screw fixation (97%, n = 29) and intramedullary nailing (3.3%, n = 1). Results We found 25 (8.5%) reoperations, and 17 (5.8%) patients had 18 systemic complications: pneumonia (3.7%, n = 11), pulmonary embolism (1.3%, n = 4), sepsis (0.68%, n = 2), and fat embolism (0.34%, n = 1). No factors were independently associated with reoperation. Logistic regression analysis demonstrated that favorable cancer status (i.e., a higher modified Bauer score: odds ratio, 0.48; 95% confidence interval, 0.29-0.80; P = .005) was independently associated with a decreased systemic complication rate. Conclusion Poor cancer status was an independent predictor of postoperative systemic complications. This could help inform the patient and anticipate postoperative problems. [ABSTRACT FROM AUTHOR]

Background En bloc vertebral resection of locally invasive T4 lung cancers led to the development of a surgical sequence for resection; posterior stabilization, reposition, thoracotomy, lobectomy, vertebrectomy, and anterior spine stabilization in 1 procedure. This technique expanded indications for vertebrectomy to selected patients with sarcoma and metastatic disease. We review our experience to identify areas for clinical improvement. Methods Operative case logs were cross-checked with billing data from 2003 to 2014 with Current Procedural Terminology (CPT, American Medical Association) codes for vertebrectomy. Thirty-two cases involving en bloc resection of malignancy invading at least 1 thoracic vertebra were selected. Outcomes data were analyzed using summary statistics. Results Series includes 14 men and 18 women, median age 50 years. Twenty-five patients (78%) received preoperative chemoradiation. Nineteen total and 13 partial vertebrectomy were performed. Average number of vertebrae resected was 1.6 (range, 1 to 4). Median operative length was 8.5 hours (range, 2.8 to 14.5), mean blood loss 923 mL (SD ± 477 mL), and median length of stay 8 days (range, 3 to 56). Major morbidity followed 56% of cases. Thirty-day mortality was 3%. Overall median survival was 43.6 months, 1-year survival was 73.6%, and 5-year survival was 40.3%. Conclusions En bloc vertebrectomy for malignant disease is feasible. Our 1 stage and 2 team approach allows completion of the operation within a standard day, but is associated with long operative time. Complication rates may improve with decreased operative times. Review of available data warrants future prospective studies. [ABSTRACT FROM AUTHOR]

Adult congenital scoliosis is more common that congenital kyphosis or lordosis. It is usually present at birth and may remain untreated until adulthood, at which point treatment may be needed for neuro, profession, pulmonary dysfunction, or loss of function. Treatment methods include posterior fusion and instrumentation with or without osteotomies, anterior/posterior fusion with or without osteotomies, or resection and posterior vertebral column resection. The surgical procedures are complex and of high risk with significant morbidity. Current segmental instrumentation systems afford a three dimensional correction of deformity with acceptable complication rates and good outcomes in the properly selected patient. [ABSTRACT FROM AUTHOR]

In this work, we have inserted the ion-heme group characterizing human blood in a class of synthetic, dendrimeric macromolecules, to evaluate a series of structural and physico-chemical properties related to the possible biological activity of these polymers. To this purpose, we have performed a complete series of investigations of five dendrimer generations both in vacuum and in water by molecular mechanics/dynamics simulations. To mimic oxygen binding, we have studied the same molecules in which the protoporphyrinic core was complexed to a Fe(II)–O2–hystidine residue. The main results of this study have led us to conclude that all dendrimer generations can bind oxygen stably, the fifth generation being the most affine to the myoglobin molecule, the natural carrier of blood oxygen. [Copyright &y& Elsevier]

Laboratory values have been found to be useful predictive measures of survival following surgery. The utility of laboratory values for prognosticating outcomes among patients with spinal metastases has not been studied. To determine the prognostic capacity of laboratory values at presentation including white blood cell (WBC) count, serum albumin and platelet-lymphocyte ratio (PLR) in patients with spinal metastases. Retrospective review of records from two tertiary care centers (2005-2017). Patients, aged 40-80, who received operative or nonoperative management for spinal metastases. Survival, complications or hospital readmissions within 90 days of treatment and a composite measure for treatment failure accounting for changes in ambulatory function and mortality at 6 months following presentation. Multivariable Cox proportional hazard regression analysis was used to analyze the relationship between laboratory values and length of survival, adjusting for confounders. Multivariable logistic regression was used in analyses related to 6-month and 1-year mortality, complications, readmissions and treatment failure. A scoring rubric was developed based on the performance of laboratory values in the multivariable tests. Internal validation was performed using a bootstrap simulation that consisted of sampling with replacement and 1,000 replications. We included 1,216 patients. Thirty-seven percent of patients received a surgical intervention and 63% were treated nonoperatively. Median survival for the cohort as a whole was 255 days (inter-quartile range 93-642 days). PLR (HR 1.53; 95% CI 1.29, 1.80; p<0.001) and albumin (HR 0.54; 95% CI 0.45, 0.64; p<0.001) were significantly associated with survival, while WBC count (HR 1.08; 95% CI 0.86, 1.36; p=0.50) was not associated with this outcome. Similar findings were encountered for 6-month and 1-year mortality as well as the composite measure for treatment failure. PLR and albumin performed well in our scoring rubric and findings were preserved in the bootstrapping validation. Individuals with low serum albumin and elevated PLR should be advised regarding the impact of these laboratory markers on outcomes including survival, irrespective of treatments received. An effort should also be made to optimize nutrition and PLR, if practicable, prior to treatment to minimize the potential for development of adverse events. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Background Context: Studies regarding treatment of spinal metastases are critical to evidence-based decision-making. However, variation exists in how a key outcome, ambulatory function, is assessed.Purpose: To characterize the sources and tools investigators have used to evaluate ambulatory function as an outcome following treatment of spinal metastases. We also sought to understand the ways ambulatory function has been conceptualized in prior studies.Study Design: Systematic review of the literature.Patient Sample: We identified 44 published studies for inclusion. Samples within these investigations ranged from 20 to 2,096 subjects.Outcome Measures: We describe the methods investigators have used to evaluate ambulatory function following treatment for spinal metastases.Methods: We conducted a systematic review through PubMed, Scopus and Web of Science following PRISMA guidelines. We included studies that consisted of adult patients receiving operative or non-operative treatment for spinal metastases. We also required that study investigators specified post-treatment ambulatory function as an outcome. We recorded year of publication, study design, types of spinal metastases included in the study, treatments employed, and sample size. We also described the source (medical record, study-specific observer and/or provider, patient and/or participant), tool (standardized measure, quantitative, qualitative) and concept (eg, ambulatory vs. non-ambulatory; independent ambulation vs. ambulatory with assistance vs. non-ambulatory) used to assess ambulatory function.Results: We found the plurality of studies relied on medical record documentation as their source. Amongst prospective studies, only a minority used a quantitative measure (eg, prespecified degree of walking ability) to assess ambulatory function. Most studies conceptualized ambulatory function as a dichotomized outcome, typically ambulatory versus non-ambulatory or a similar equivalent.Conclusions: Wide variation exists in how ambulatory function is defined in studies involving patients with spinal metastases. We suggest several improvements that will allow a more robust assessment of the quality and quantity of ambulatory function among patients treated for spinal metastases. [ABSTRACT FROM AUTHOR]

Purpose Assessing the stability of spinal metastases is critical for making treatment decisions. The spinal instability neoplastic score (SINS) was developed by the Spine Oncology Study Group to categorize tumor-related lesions; however, data describing its utility in predicting fractures in patients with spinal metastases are limited. The purpose of this study is to assess the validity of SINS in predicting new or worsening fracture after radiation therapy (RT) to spine metastases. Methods and materials This is a retrospective analysis of patients treated with conventional RT alone (median total dose, 30 Gy; range, 8-47 Gy; median number of fractions, 10; range, 1-25) for spinal metastasis at Dana-Farber/Brigham and Women's Cancer Center from 2006 to 2013. SINS was calculated for each lesion (range, 0-18). The primary endpoint was time from RT start to radiographically documented new or worsening fracture or last disease assessment. Results A total of 203 patients and 250 lesions were included in analysis. The percentages of lesions with SINS of 0 to 6, 7 to 12, and 13 to 18 were 38.8%, 54.8%, and 6.4%, respectively. Of 250 lesions, 20.4% developed new or worsening fractures; 14.4% for SINS 0 to 6, 21.2% for SINS 7 to 12, and 50.0% for SINS 13 to 18. Multivariate analysis adjusted for sex, age, Eastern Cooperative Oncology Group, histology, and total dose indicated that, compared with stable lesions (SINS 0-6), potentially unstable lesions (SINS 7-12) demonstrated a greater likelihood of new or worsening fracture that was not statistically significant (hazard ratio, 1.66; 95% confidence interval, 0.85-3.22; P = .14), and unstable lesions (SINS 13-18) were significantly more likely to develop to new or worsening fracture (hazard ratio, HR,4.37, 95% confidence interval, 1.80-10.61; P = .001). Conclusions In this study of patients undergoing RT for spinal metastases, 20.4% developed new or worsening vertebral fractures. SINS is demonstrated to be a useful tool to assess fracture risk after RT. [ABSTRACT FROM AUTHOR]

Purpose To evaluate patterns and predictors of local failure in patients undergoing postoperative radiation therapy (RT) for osseous metastases. Methods and materials Patients undergoing postoperative RT for bone metastases between June 2008 and January 2012 were retrospectively reviewed. Patterns of local failure were assessed, and Fine and Gray’s univariable and multivariable analyses (MVA) were used to evaluate factors associated with local progression, including dose intensity of RT (biological equivalent dose, BED, Gy 10 ) and percent coverage of the surgical hardware by the RT fields. Additional predictors were similarly assessed, including patient (eg, age, performance status), disease (eg, tumor type, metastasis site), and treatment (eg, interval from surgery to RT) characteristics. Results A total of 82 cases were followed for a median of 4.3 months (11.5 months among living patients) after treatment completion. Median BED was 39 Gy 10 (range, 14-60), and RT fields covered an average of 71% (standard deviation, 26%) of the hardware. Fourteen cases (17%) experienced local progression. Although most (71%) failures occurred within the RT fields, 29% occurred marginally or out of field, but adjacent to surgical hardware. Increasing coverage of the surgical hardware by RT fields was associated with a reduced risk of local failure in MVA (hazard ratio [HR], 0.10; 95% confidence interval [CI], 0.012-0.82; P = .03), whereas a greater risk of failure was seen with increasing time between surgery and RT (HR, 1.03; 95% CI, 1.01-1.06; P = .01). Extremity rather than spinal site trended toward a greater risk of failure but did not reach significance (HR, 3.79; 95% CI, 0.96-14.89; P = .057). BED ≥ 39 Gy 10 did not predict local failure ( P = .51) in MVA. Conclusions Current strategies achieve good outcomes after postoperative RT for osseous metastases. Greater coverage of the surgical hardware with RT fields and avoiding delays between surgery and postoperative RT should be considered to reduce recurrence risk for patients with bone metastases requiring surgical stabilization. [ABSTRACT FROM AUTHOR]

Mortality in patients with spinal epidural abscess (SEA) remains high. Accurate prediction of patient-specific prognosis in SEA can improve patient counseling as well as guide management decisions. There are no externally validated studies predicting short-term mortality in patients with SEA. The purpose of this study was to externally validate the Skeletal Oncology Research Group (SORG) stochastic gradient boosting algorithm for prediction of in-hospital and 90-day postdischarge mortality in SEA. Retrospective, case-control study at a tertiary care academic medical center from 2003 to 2021. Adult patients admitted for radiologically confirmed diagnosis of SEA who did not initiate treatment at an outside institution. In-hospital and 90-day postdischarge mortality. We tested the SORG stochastic gradient boosting algorithm on an independent validation cohort. We assessed its performance with discrimination, calibration, decision curve analysis, and overall performance. A total of 212 patients met inclusion criteria, with a short-term mortality rate of 10.4%. The area under the receiver operating characteristic curve (AUROC) of the SORG algorithm when tested on the full validation cohort was 0.82, the calibration intercept was -0.08, the calibration slope was 0.96, and the Brier score was 0.09. With a contemporaneous and geographically distinct independent cohort, we report successful external validation of a machine learning algorithm for prediction of in-hospital and 90-day postdischarge mortality in SEA. [ABSTRACT FROM AUTHOR]

Several investigations have touted that surgery for spinal metastases not only preserves ambulatory ability, but also improves survival. Many of these investigations may be confounded by selection and indication bias. Controversy remains regarding the utility of surgery for patients with spinal metastases and no neurologic deficits. We planned an analysis that accounted for confounding by indication and compared patients treated operatively and nonoperatively for spinal metastases who were enrolled in the Prospective Observational study of Spinal metastasis Treatment (POST). We considered 87 instances of surgical intervention and 122 cases of nonoperative treatment enrolled between 2017-2019. Survival at one year following treatment initiation. The primary outcome was survival at one year following treatment initiation. The primary predictor was treatment, categorized as operative or nonoperative management. Crossovers were handled via statistical cloning. Unadjusted comparisons between the operative and nonoperative cohorts were made using chi-square tests for categorical variables and the Wilcoxon rank-sum test for non-parametric, continuous data. Survival was assessed using Kaplan-Meier curves. We developed a propensity score around the likelihood for surgical intervention using age, biologic sex, co-morbidities, primary tumor, neurologic symptoms and NESMS at presentation based on our conceptual model. The propensity score was used in final adjusted models for survival at one year. Fifty percent of the cohort died by one year following presentation. In the operative group, the mortality rate was 46% at one year, as compared to 54% in the nonoperative cohort. This represented a 25% reduction in the odds of mortality (OR 0.75; 95% CI 0.43, 1.30) but was not significantly different (p=0.3). Following propensity score adjustment, surgical intervention offered a 28% reduction in the odds of mortality (OR 0.72; 95% CI 0.40, 1.29) but still did not demonstrate statistical significance (p=0.27). While it is interesting that propensity adjustment slightly increased the advantage for surgery, the estimated 25%-28% reduction in the odds of mortality should be balanced against the risks associated with these high-intensity interventions and the relatively high mortality rate, irrespective of treatment strategy. This may be especially important in instances where the metastatic process is largely asymptomatic. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Abstract: Mesoscale molecular simulations, based on parameters obtained through atomistic molecular dynamics and Monte Carlo calculations, have been used for modeling and predicting the behavior of PET/PEN blends. Different simulations have been performed in order to study and compare pure homopolymer blends with blends characterized by the presence of PET/PEN block copolymers acting as compatibilizer. A many-scale molecular modeling strategy was devised to evaluate PET/PEN blend characteristics, simulate phase segregation in pure PET/PEN blends, and demonstrate the improvement of miscibility due to the presence of the transesterification reaction products. The behavior of distribution densities and order parameters of the compatibilized blends demonstrates that mixing properties improve significantly, in agreement with experimental evidences. Barrier properties such as oxygen diffusivity and permeability have also been evaluated by finite element simulations. Accordingly, many-scale modeling seems to be a successful way to estimate PET/PEN blend properties and behavior upon different concentrations and processing conditions. [Copyright &y& Elsevier]

Molecular simulation techniques are used to explore and characterize the atomic scale structure, and to predict binding energies and basal spacing of polymer/clay nanocomposites based on polypropylene (PP) and maleated polypropylene (PPMA), montmorillonite (MMT), and different alkylammonium ions (quats) as surfactants. Our evidences suggest that shorter hydrocarbonic chains are more effective in producing favorable binding energies with respect to longer ones, and the substitutions of hydrogen atoms with polar groups on the quaternary ammonium salt (quat) generally results in greater interaction between quat and both polymer and clay. Under the hypothesis, that montmorillonite platelets are uniformly dispersed in a polymer matrix, the modified polypropylene yields higher interfacial strength with clay than neat polypropylene. The use of neat PP and quats with higher molecular volume offer the higher values of the basal spacing and thus, in principle, they should be more effective in the exfoliation process. [Copyright &y& Elsevier]

Three-dimensional polyphenylene dendrimers (PDs) can be prepared in ways that enable control of their shape. Their structures may be used as scaffolds with a wide variety of functionality, enabling them to be used as functional nanoparticles with a large range of possible applications, ranging from light emitting devices to biological sensors or drug delivery tools. As PDs have been synthesized only recently, their structural and chemico-physical characterization is still in its infancy. Accordingly, in this paper the shape and internal organization of three PD families based on three different cores were probed by accurate, atomistic molecular dynamics simulations (MD). Particular care was taken to ensure complete structural equilibration by implementing an MD simulated annealing protocol prior to evaluation of the molecular structure and dynamics. All dendrimer families were found to be characterized by molecular dimensions in the nano-range, and by a shape-persistent, non-spherical structure, of molecular fractal dimension around 2.5–2.6, and of surface fractal dimension practically constant and almost equal to 2 with increasing generations in all cases. The MD analysis revealed also that, for this type of dendrimers, the starburst limited generation is presumably located in correspondence of the third generation. [Copyright &y& Elsevier]

RENASCENT is a prospective, multi-center first-in-human clinical study to evaluate the clinical performance of the novel sirolimus-eluting 150-μm strut thickness FORTITUDE® BRS for percutaneous coronary intervention of single de novo coronary lesions. FORTITUDE® BRS was tested in a prospective study in Italy and Colombia. Study objectives were in-scaffold angiographic late lumen loss (LLL) measured by quantitative coronary angiography and target vessel failure (TVF) defined as the composite rate of cardiac death, target vessel myocardial infarction or ischemia driven target lesion revascularization (TLR) at 9- and 24-months with clinical results up to 36-months. A total of 63 patients were enrolled. All patients underwent lesion pre-dilatation and 22 patients (34.9%) underwent post-dilatation. Clinical device and procedural success was 98.4% (62/63 patients) and 96.8% (61/63 patients) respectively. At 9-months, TVF occurred in 3/61 (4.9%) of the patients including 2 peri-procedural MI and one ischemia-driven TLR. Between 9- to 24-months, ischemia-driven TLR occurred in 3 additional patients (4.9%) including 1 patient who presented with very late ST after stopping all medications. There were no further TVF between 24- and 36-months. In this multi-center prospective study, the FORTITUDE® BRS was shown to be safe and effective in the treatment of single coronary lesions with low levels of TVF and LLL at 9- and 24-months. It was shown to be clinically safe upto 36-months follow-up. • First-in-human study evaluating 150 μm FORTITUDE bioresorbable scaffold. • Low levels of target vessel failure and late lumen loss at 9- and 24-months. • FORTITUDE® BRS was shown to be safe and effective upto 36-months follow-up. [ABSTRACT FROM AUTHOR]

Background Context: There are several prognostic scores available that intend to inform decision-making for patients with spinal metastases. Many of these have not been found to reliably predict survival across the continuum of care. Recently, our group developed the New England Spinal Metastasis Score (NESMS). While the NESMS demonstrated many of the necessary attributes of a useful prediction tool, it has yet to be validated prospectively.Purpose: To describe the prospective observational study of spinal metastasis treatment (POST). This investigation examined the performance of the NESMS, compared its predictive capacity with other scoring systems and determined its ability to identify patients who benefit the most from surgery.Study Design: Prospective observational study at two medical centers.Patient Sample: Patients age 18 and older with spinal metastases involving the spine.Outcome Measures: Survival, post-treatment morbidity and health-related quality of life outcomes.Methods: The POST study assessed patients at baseline and at 1-month, 3-month, 6-month, and 12-month time-points. During the baseline assessment patient demographics, past medical history and assessment of co-morbidities, surgical history, primary tumor histology, and ambulatory status were recorded along with the designated treatment strategy (eg, operative or nonoperative). The NESMS and other predictive scores for each patient were calculated based on baseline data. Study-specific surveys administered at all time-points consisted of the EuroQuol 5-Dimension and Short-Form (SF)-12, Visual Analog Scale (VAS) for pain, and PROMIS assessment of global health.Results: Two hundred patients were enrolled in POST from 2017 to 2019. Patients were followed to one of the two predetermined study end-points (ie, mortality, or completion of the 12-month follow-up). Survival was considered the principle dependent variable. Post-treatment morbidity and health-related quality of life outcomes were considered secondarily. Analyses, by aim, relied on Cox proportional hazards regression, repeated measures logistic regression, propensity score matching and multivariable logistic regression.Conclusion: The POST's findings are anticipated to provide evidence regarding the prognostic capabilities of the NESMS as well as that of other popular grading schemes for survival, post-treatment complications and physical as well as mental function. [ABSTRACT FROM AUTHOR]

Background Context: In-hospital and short-term mortality in patients with spinal epidural abscess (SEA) remains unacceptably high despite diagnostic and therapeutic advancements. Forecasting this potentially avoidable consequence at the time of admission could improve patient management and counseling. Few studies exist to meet this need, and none have explored methodologies such as machine learning.Purpose: The purpose of this study was to develop machine learning algorithms for prediction of in-hospital and 90-day postdischarge mortality in SEA.Study Design/setting: Retrospective, case-control study at two academic medical centers and three community hospitals from 1993 to 2016.Patients Sample: Adult patients with an inpatient admission for radiologically confirmed diagnosis of SEA.Outcome Measures: In-hospital and 90-day postdischarge mortality.Methods: Five machine learning algorithms (elastic-net penalized logistic regression, random forest, stochastic gradient boosting, neural network, and support vector machine) were developed and assessed by discrimination, calibration, overall performance, and decision curve analysis.Results: Overall, 1,053 SEA patients were identified in the study, with 134 (12.7%) experiencing in-hospital or 90-day postdischarge mortality. The stochastic gradient boosting model achieved the best performance across discrimination, c-statistic=0.89, calibration, and decision curve analysis. The variables used for prediction of 90-day mortality, ranked by importance, were age, albumin, platelet count, neutrophil to lymphocyte ratio, hemodialysis, active malignancy, and diabetes. The final algorithm was incorporated into a web application available here: https://sorg-apps.shinyapps.io/seamortality/.Conclusions: Machine learning algorithms show promise on internal validation for prediction of 90-day mortality in SEA. Future studies are needed to externally validate these algorithms in independent populations. [ABSTRACT FROM AUTHOR]

Decisions for operative or nonoperative management remain challenging in patients with spinal metastases, especially when life expectancy and quality of life are not easily predicted. To evaluate the effects of operative and nonoperative management on maintenance of ambulatory function and survival in patients treated for spinal metastases. Retrospective study with propensity match. Patients treated for spinal metastases at one of 2 academic medical centers (2005-2017). Ambulatory function at 6 months following presentation was our primary outcome. Survival at 6 months and 1 year were secondary outcomes. We used propensity matching to yield an analytic sample in which operatively and nonoperatively treated patients were similar with respect to key baseline covariates. We included patients treated for spinal metastases between 2005-2017, who – at presentation - were 40-80 years old and independent ambulators, with <5 medical comorbidities. We evaluated the influence of operative compared to nonoperative care on ambulatory function at 6 months as well as survival at 6 months and 1 year. We identified 929 individuals eligible for inclusion, with 402 (201 operative, 201 nonoperative) retained following propensity score matching. Patients treated operatively had a lower likelihood than those treated nonoperatively of being nonambulatory at 6-months following presentation (3% vs 16%, RR 0.16; 95% CI 0.06, 0.46), as well as reduced risks of 6-month (20% vs 29%, RR 0.69; 95% CI 0.49, 0.98) and 1-year mortality (37% vs 51%, RR 0.74; 95% 0.59, 0.92). Our results indicate that patients treated operatively were less likely to lose ambulatory function at 6-months following presentation than those managed nonoperatively. In patients with spinal metastases, our data can be incorporated into discussions about the treatments that align best with the patients' preferences regarding surgical risk, mortality and ambulatory status. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Several retrospective series support the use of operative or nonoperative interventions for the treatment of patients with spinal metastases. While surgery in several contexts has been shown to result in superior outcomes regarding longevity and ambulatory function, some of these conclusions may result from selection and indication bias. While nonoperative strategies avoid the complications of surgery, treatment results may not always be as efficacious and surgical intervention following nonoperative care has been shown to have inferior results. At present, there is no rigorously performed prospective study focused on functional outcomes for patients undergoing operative and nonoperative management for spinal metastases. We present preliminary results of an ongoing prospective observational study contrasting functional outcomes between patients receiving surgery, or nonoperative care, for spinal metastatic disease. Prospective observational study conducted at two academic medical centers (2017-present). A total of 178 patients receiving operative or nonoperative treatment for spinal metastases. Enrolled patients receive an initial intake evaluation, including assessment of demographics, past medical history, surgical history, radiology, primary tumor histology, ambulatory status and functional evaluation. The functional evaluation consists of study-specific surveys: EuroQuol 5-Dimension (EQ5D) profile and Short-Form (SF)-12 (assessment of state of health and physical/mental function), visual analog scale (VAS) for pain (assessment of current level of pain) and PROMIS Measures (assessment of global health). Completion of the EQ5D, SF-12, VAS pain scale, PROMIS (appendix) and a determination of ambulatory status will occur at the 1-month, 3-month, 6-month and 12-month time-points. Survival is the principle dependent variable with clinically meaningful survival defined as three months or greater. Treatment-associated complications and functional outcomes at time-points up to one year will be considered secondary dependent variables. Patients will be categorized into groups based on the clinically meaningful time-points of 3 months survival, 6 months survival or survival to one year or greater. Patients who received surgery will be compared to those managed nonoperatively using propensity-matched techniques. The propensity score will be developed for surgical intervention as the dependent variable using a logistic regression model. Patient matching will be made based on a propensity score. The capacity of the predictive score to inform outcomes in the setting of surgical or nonoperative intervention will then be evaluated in the propensity matched model and also using a mixed-effects model. Phase I enrollment consists of 178 patients. The average age of the cohort is 60.4 (SD 13.1). Fifty-six percent of the population is male. Eighty-five percent of the population is white. Average body mass index is 27.0 and average co-morbidities are 2.4. Breast (19%) and lung cancer (18%) are the most common primary tumors. Thirty-seven percent of metastases were isolated to the thoracic region and 17% in the lumbar region, while 33% involved multiple regions. Thirty-seven percent of the cohort has been treated surgically. At present, 58% of the population is still alive. Surgical intervention (24/65; 37% mortality) is not currently associated with superior survival as compared to nonoperative treatment (50/109; 46% mortality; p=0.25). We anticipate that the results of this analysis will provide high quality evidence that accurately identifies those patients who will maximally benefit from surgical intervention with the lowest risk of perioperative morbidity. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Increasing prevalence of metastatic disease has been accompanied by increasing rates of surgical intervention. Current tools have poor to fair predictive performance for intermediate (90-day) and long-term (one-year) mortality. The purpose of this study was to develop predictive algorithms for spinal metastatic disease at these time points and to provide patient-specific explanations of the predictions generated by these algorithms. Retrospective review was conducted at two large academic medical centers. Patients undergoing initial operative management for spinal metastatic disease between January 2000 and December 2016. Ninety-day and one-year overall survival. Five models (penalized logistic regression, random forest, stochastic gradient boosting, neural network, and support vector machine) were developed to predict ninety-day and one-year mortality. Overall, 732 patients were identified with ninety-day and one-year mortality rates of 181 (25.1%) and 385 (54.3%), respectively. The stochastic gradient boosting algorithm had the best performance for 90-day mortality and one-year mortality. On global variable importance assessment, albumin, primary tumor histology, and performance status were the three most important predictors of 90-day mortality. The final models were incorporated into an open access web application able to provide predictions as well as patient-specific explanations of the results generated by the algorithms. The application can be found at: https://sorg-apps.shinyapps.io/spinemetssurvival/ Preoperative estimation of 90-day and one-year mortality was achieved with assessment of more flexible modeling techniques such as machine learning. Integration of these models into applications and patient-centered explanations of predictions represent opportunities for incorporation into health care systems as decision tools in the future. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Background Context: En bloc resection and reconstruction (EBR) in patients with spinal malignancy aims to achieve local disease control. This is an invasive procedure with significant alterations of the physiological anatomy and subsequently, the spino-pelvic alignment. Sagittal spinal parameters are useful measurements to objectively identify disproportionate alignment on a radiograph. In the field of spinal deformities, there is increasing evidence for a relationship between sagittal alignment and patient reported outcomes.Purpose: To determine sagittal spino-pelvic alignment after EBR in patients with spinal malignancies and the effect of these parameters on surgical and patient reported outcomes.Study Design: A retrospective case series.Methods: We included 35 patients who underwent EBR for spinal malignancies between 2000 and 2018. Radiographic measurements were performed using semi-automatic software; the parameters included were pelvic incidence (PI), sacral slope, pelvic tilt (PT), global tilt and lumbar lordosis. We calculated PI-based Global Alignment and Proportion (GAP) scores and prospective patient reported outcome scores Patient-Reported Outcome Measurement Information System-Physical Function (PROMIS-PF) were used.Results: Twenty-one (60%) patients filled out the PROMIS-PF score at a median of 16 months (Interquartile Range (IQR) 4-108) after surgery with a median score of 39 (IQR 32-42), the median GAP score was 7 (IQR 5-9). Bivariate analysis showed no statistically significant relationship between GAP score and instrumentation failure or need for revision surgery. Multivariable analysis of GAP score and PROMIS-PF score corrected for local disease recurrence showed a statistically significant correlation coefficient of -1.721 (p=.026; 95%CI=-3.216, -0.226).Conclusion: In this cohort, all patients had a moderate or severe disproportioned spinal alignment after EBR and reconstruction surgery. The degree of sagittal spino-pelvic misalignment after EBR for spinal malignancies seems to be associated with patient reported health status in terms of PROMIS-PF scores. Further research with a larger patient cohort and standardized imaging and follow-up protocols is necessary in order to accurately use sagittal alignment as a predictive value for instrumentation failure and revision surgery. [ABSTRACT FROM AUTHOR]

Abstract Background Context Postoperative morbidity may offset the potential benefits of surgical treatment for spine metastatic disease; hence, risk factors for postoperative complications and reoperations should be taken into considerations during surgical decision-making. In addition, it remains unknown whether complications and reoperations shorten these patients' survival. Purpose We aimed to describe and identify factors associated with having a complication within 30 days of index surgery as well as factors associated with having a subsequent reoperation. Furthermore, we assessed the effect of 30-day complications and reoperations on the patients' postoperative survival, as well as described neurologic changes after surgery. Study Design Retrospective cohort study. Patient Sample We included 647 patients 18 years and older who had surgery for metastatic disease in the spine between January 2002 and January 2014 in one of two affiliated tertiary care centers. Outcome Measures Our primary outcomes were complications within 30 days after surgery and reoperations until final follow-up or death. Methods We used multivariate logistic regression to identify risk factors for 30-day complications and reoperations. We used the Cox regression analysis to assess the effect of postoperative complications and reoperations on survival. Results From 647 included patients, 205 (32%) had a complication within 30 days. The following variables were independently associated with 30-day complications: lower albumin levels (odds ratio [OR]: 0.69, 95% confidence interval [CI]=0.49–0.96, p=.021), additional comorbidities (OR=1.42, 95% CI=1.00–2.01, p=.048), pathologic fracture (OR=1.41, 95% CI=0.97–2.05, p=.031), three or more spine levels operated upon (OR=1.64, 95% CI=1.02–2.64, p=.027), and combined surgical approach (OR=2.44, 95% CI=1.06–5.60, p=.036). One hundred and fifteen patients (18%) had at least one reoperation after the initial surgery; prior radiotherapy (OR=1.56, 95% CI=1.07–2.29, p=.021) to the spinal tumor was independently associated with reoperation. 30-day complications were associated with worse survival (hazard ratio [HR]=1.40, 95% CI=1.17–1.68, p<.001), and reoperation was not significantly associated with worse survival (HR=0.80, 95% CI=0.09–1.00, p=.054). Neurologic status worsened in 42 (6.7%), remained stable in 445 (71%), and improved in 140 (22%) patients after surgery. Conclusions Three or more spine levels operated upon and prior radiotherapy should prompt consideration of a preoperative plastic surgery consultation regarding soft tissue coverage. Furthermore, if time allows, aggressive nutritional supplementation should be considered for patient with low preoperative serum albumin levels. Surgeons should be aware of the increase in complications in patients presenting with pathologic fracture, undergoing a combined approach, and with any additional preoperative comorbidities. Importantly, 30-day complications were associated with worsened survival. [ABSTRACT FROM AUTHOR]