Clinical and Economic Impact of Proximal Junctional Kyphosis on Pediatric and Adult Spinal Deformity Patients.

The common goal of pediatric and adult spinal reconstructive procedures is to minimize long-term risk of disability, pain, and mortality. A common complication that has proved particularly problematic in the adult spinal deformity population and that has been an area of increased research and clinical focus is proximal junctional kyphosis (PJK). The incidence of PJK ranges from 10%-40% based on criteria used to define the condition. Clinically, PJK complication is associated with increased pain, decreased self-image and Scoliosis Research Society scores, and severe neurological injuries affecting the patient's quality of life. Economically, direct costs of PJK complication-associated revision surgery ranges from $20,000 to $120,000, which places an enormous burden on patients, providers, and payers. To mitigate the risk of PJK occurrence postoperatively, it is paramount to develop consistent guidelines in defining and classifying PJK in addition to extensive preoperative planning and risk stratification that is patient specific. This article will provide an overview on the clinical and economic impact of PJK in pediatric and adult spine deformity patients with an emphasis on the role of patient factors and predictive analytics, challenges in developing a consistent PJK classification, and current treatment and prevention strategies.

Diagnosis-Related Group-Based Payments for Adult Spine Deformity Surgery Significantly Vary across Centers: Results from a Multicenter Prospective Cohort Study.

BACKGROUND: To investigate the variation in total episode-of-care (EOC) payment and quality-adjusted life-year (QALY) gain for complex adult spine deformity surgeries in the United States, adjusting for case type and surgeon preferences. METHODS: Patients aged >18 years with adult spine deformity with Medicare Severity-Diagnosis-Related Groups (DRGs) 453-460 and a minimum of 2 years of follow-up from index surgery were included. Index and total payments were calculated using Medicare's Inpatient Prospective Payment System. All costs were adjusted for inflation to 2020 U.S. dollar values. QALYs gained were calculated using baseline, 1-year, and 2-year Short-Form 6D scores. Mixed-effect models were used to estimate the proportion of variation in total EOC payment and QALY gain. RESULTS: A total of 330/543 patients from 6 sites were included. Mean age was 62.4 ± 11.9 years, 79% were women, and 92% were white. The mean index and total EOC payment were $77,302 and $93,182, respectively. Patients gained on average 0.15 QALY (P < 0.0001) 2 years after surgery. In unadjusted analysis, 39% of the variation in total EOC payment across the 6 centers was attributable to relative weight of DRG and base rate. Adjusting for patient and procedural factors increased the proportion of variation in total EOC payments across the centers to 56%. Less than 2% of the variation in QALY gain was observed across the 6 centers. CONCLUSIONS: Medicare-based payments for complex spine deformity fusions are primarily driven by relative weight of the DRG and the hospital's base rate. Patient and procedural factors are unaccounted for in the DRG-based payments made to the providers.

Integrating Population Health Strategies into Primary Care: Impact on Outcomes and Hospital Use for Low-Income Adults.

Objective: Our objectives were two-fold: 1) To evaluate the benefits of population health strategies focused on social determinants of health and integrated into the primary care medical home (PCMH) and 2) to determine how these strategies impact diabetes and cardiovascular disease outcomes among a low-income, primarily minority community. We also investigated associations between these outcomes and emergency department (ED) and inpatient (IP) use and costs. Design: Retrospective cohort. Setting: Community-based PCMH: Baylor Scott & White Health and Wellness Center (BSW HWC). Patients/Participants: All patients who attended at least two primary care visits at BSW HWC within a 12-month time span from 2011-2015. Methods: Outcomes for patients participating in PCMH only (PCMH) as compared to PCMH plus population health services (PCMH+PoPH) were compared using electronic health record data. Main Outcomes: Diastolic and systolic blood pressure, hemoglobin A1c, ED visits and costs, and IP hospitalizations and costs were examined. Results: From 2011-2015, 445 patients (age=46±12 years, 63% African American, 61% female, 69.5% uninsured) were included. Adjusted regression analyses indicated PCMH+PoPH had greater improvement in diabetes outcomes (prediabetes HbA1c= -.65[SE=.32], P=.04; diabetes HbA1c= -.74 [SE=.37], P<.05) and 37% lower ED costs than the PCMH group (P=.01). Worsening chronic disease risk factors was associated with 39% higher expected ED visits (P<.01), whereas improved chronic disease risk was associated with 32% fewer ED visits (P=.04). Conclusions: Integrating population health services into the PCMH can improve chronic disease outcomes, and impact hospital utilization and cost in un- or under-insured populations.

Antibiotics prior to age 2 years have limited association with preschool growth trajectory.

BACKGROUND: Prior studies of early antibiotic use and growth have shown mixed results, primarily on cross-sectional outcomes. This study examined the effect of oral antibiotics before age 24 months on growth trajectory at age 2-5 years. METHODS: We captured oral antibiotic prescriptions and anthropometrics from electronic health records through PCORnet, for children with ≥1 height and weight at 0-12 months of age, ≥1 at 12-30 months, and ≥2 between 25 and 72 months. Prescriptions were grouped into episodes by time and by antimicrobial spectrum. Longitudinal rate regression was used to assess differences in growth rate from 25 to 72 months of age. Models were adjusted for sex, race/ethnicity, steroid use, diagnosed asthma, complex chronic conditions, and infections. RESULTS: 430,376 children from 29 health U.S. systems were included, with 58% receiving antibiotics before 24 months. Exposure to any antibiotic was associated with an average 0.7% (95% CI 0.5, 0.9, p < 0.0001) greater rate of weight gain, corresponding to 0.05 kg additional weight. The estimated effect was slightly greater for narrow-spectrum (0.8% [0.6, 1.1]) than broad-spectrum (0.6% [0.3, 0.8], p < 0.0001) drugs. There was a small dose response relationship between the number of antibiotic episodes and weight gain. CONCLUSION: Oral antibiotic use prior to 24 months of age was associated with very small changes in average growth rate at ages 2-5 years. The small effect size is unlikely to affect individual prescribing decisions, though it may reflect a biologic effect that can combine with others.

Reaching the medicare allowable threshold in adult spinal deformity surgery: multicenter cost analysis comparing actual direct hospital costs versus what the government will pay.

STUDY DESIGN: Retrospective multicenter cost analysis. OBJECTIVE: To (1) determine if index episode of care (iEOC) costs of Adult Spinal Deformity (ASD) surgeries are below the Medicare Allowable (MA) threshold, and (2) identify variables that can predict iEOC cases that are below MA. Previous studies have suggested that actual direct hospital cost of Adult Spinal Deformity (ASD) surgery is higher than Medicare Allowable (MA) rates, which has become the benchmark reimbursement target for hospital accounting systems. METHODS: From a prospective, multicenter ASD surgical database, patients undergoing long instrumented fusions (> 5 level) with cost data were identified. iEOC cost was calculated utilizing actual direct hospital cost. MA rates were calculated using hospital specific, year-appropriate CMS Inpatient Pricer Payment System. Recursive partitioning identified potentially modifiable variables that can predict iEOC cost < MA. RESULTS: Administrative direct cost data from 210 patients were obtained from 4 of 11 centers. Ninety-five (45%) patients had iEOC cost < MA. There was significant variation across the four centers in both iEOC cost ($56,788-$78,878, p < 0.0001) and reimbursement ($40,623-$91,351, p < 0.0001) across deformity-specific DRGs (453,454,456,457). Academic centers were more likely to have iEOC costs < MA (67.2% vs 8.9%, p < 0.0001). Recursive partitioning (r2 = 0.309) identified rhBMP-2 use of < 24 mg, sagittal plane deformity, a combined anterior/posterior approach, and an SF36-MCS < 39 as predictive for iEOC cost < MA. Performing an anterior/posterior approach reimburses between 14.7% and 121.1% more (2.2-fold) than posterior-only approach. This change in DRG allows iEOC cost to be more likely below the MA threshold. CONCLUSION: There is significant institutional (private vs academic) variation in ASD reimbursement. BMP use, deformity type, approach, and baseline mental health impact ASD surgery cost being below Medicare reimbursement. ASD surgeries with anterior/posterior approaches are in DRGs that can potentially reimburse 2.2-fold the posterior-only surgery, making it more likely to fall below the MA threshold. LEVEL OF EVIDENCE: III.

Clinical outcomes of severe COVID-19 patients receiving early VV-ECMO and the impact of pre-ECMO ventilator use.

Acute respiratory distress syndrome (ARDS) in COVID-19 patients is associated with poor clinical outcomes and high mortality rates, despite the use of mechanical ventilation. Veno-Venous Extracorporeal membrane Oxygenation (VV-ECMO) in these patients is a viable salvage therapy. We describe clinical outcomes and survival rates in 52 COVID-19 patients with ARDS treated with early VV-ECMO at a large, high-volume center ECMO program. Outcomes included arterial blood gases, respiratory parameters, inflammatory markers, adverse events, and survival rates. Patients' mean age was 47.8 ± 12.1 years, 33% were female, and 75% were Hispanic. At the end of study period, 56% (n = 29) of the patients survived and were discharged and 44% (n = 23) of the patients expired. Survival rate was 75.0% (9 out of 12) in patients placed on ECMO prior to mechanical ventilation. Longer duration on mechanical ventilation prior to ECMO intervention was associated with a 31% (aOR = 1.31, 95% CI, 1.00-1.70) increased odds of mortality after adjusting for age, gender, BMI, number of comorbid conditions, and post-ECMO ventilator days. Early and effective ECMO intervention in critical ill COVID-19 patients might be a valuable strategy in critical care settings to increase their odds of survival.

Improvement in SRS-22R Self-Image Correlate Most with Patient Satisfaction after 3-Column Osteotomy.

STUDY DESIGN: Longitudinal cohort. OBJECTIVES: The aim of this study was to examine the relationship between patient satisfaction, patient-reported outcome measures (PROMs) and radiographic parameters in adult spine deformity (ASD) patients undergoing three-column osteotomies (3CO). SUMMARY OF BACKGROUND DATA: Identifying factors that influence patient satisfaction in ASD is important. Evidence suggests Scoliosis Research Society-22R (SRS-22R) Self-Image domain correlates with patient satisfaction in patients with ASD. METHODS: This is a retrospective review of ASD patients enrolled in a prospective, multicenter database undergoing a 3CO with complete SRS-22R pre-op and minimum 2-years postop. Spearman correlations were used to evaluate associations between the 2-year SRS Satisfaction score and changes in SRS-22R domain scores, Oswestry Disability Index (ODI), and radiographic parameters. RESULTS: Of 135 patients eligible for 2-year follow-up, 98 patients (73%) had complete pre- and 2-year postop data. The cohort was mostly female (69%) with mean BMI of 29.7 kg/m2 and age of 61.0 years. Mean levels fused was 12.9 with estimated blood loss of 2695 cc and OR time of 407 minutes; 27% were revision surgeries. There was a statistically significant improvement between pre- and 2-year post-op PROMs and all radiographic parameters except Coronal Vertical Axis. The majority of patients had an SRS Satisfaction score of ≥3.0 (90%) or ≥4.0 (68%), consistent with a moderate ceiling effect. Correlations of patient satisfaction was significant for Pain (0.43, P < 0.001), Activity (0.39, P < 0.001), Mental (0.38, P = 0.001) Self-Image (0.52, P < 0.001). ODI and Short-Form-36 Physical component summary had a moderate correlation as well, with mental component summary being weak. There was no statistically significant correlation between any radiographic or operative parameters and patient satisfaction. CONCLUSION: There was statistically significant improvement in all PROMs and radiographic parameters, except coronal vertical axis at 2 years in ASD patients undergoing 3CO. Improvement in SRS Self-Image domain has the strongest correlation with patient satisfaction.Level of Evidence: 3.

Advancement of a standardised enteral feeding protocol in functional single ventricle patients following stage I palliation using cerebro-somatic near-infrared spectroscopy.

INTRODUCTION: Infants with single ventricle following stage I palliation are at risk for poor nutrition and growth failure. We hypothesise a standardised enteral feeding protocol for these infants that will result in a more rapid attainment of nutritional goals without an increased incidence of gastrointestinal co-morbidities. MATERIALS AND METHODS: Single-centre cardiac ICU, prospective case series with historical comparisons. Feeding cohort consisted of consecutive patients with a single ventricle admitted to cardiac ICU over 18 months following stage I palliation (n = 33). Data were compared with a control cohort and admitted to the cardiac ICU over 18 months before feeding protocol implementation (n = 30). Feeding protocol patients were randomised: (1) protocol with cerebro-somatic near-infrared spectroscopy feeding advancement criteria (n = 17) or (2) protocol without cerebro-somatic near-infrared spectroscopy feeding advancement criteria (n = 16). RESULTS: Median time to achieve goal enteral volume was significantly higher in the control compared to feeding cohort. There were no significant differences in enteral feeds being held for feeding intolerance or necrotising enterocolitis between cohorts. Feeding cohort had significant improvements in discharge nutritional status (weight, difference admit to discharge weight, weight-for-age z score, volume, and caloric enteral nutrition) and late mortality compared to the control cohort. No infants in the feeding group with cerebro-somatic near-infrared spectroscopy developed necrotising enterocolitis versus 4/16 (25%) in the feeding cohort without cerebro-somatic near-infrared spectroscopy (p = 0.04). CONCLUSIONS: A feeding protocol is a safe and effective means of initiating and advancing enteral nutrition in infants following stage I palliation and resulted in improved nutrition delivery, weight gain, and nourishment status at discharge without increased incidence of gastrointestinal co-morbidities.

Cost-effectiveness of surgical treatment of adult spinal deformity: comparison of posterior-only versus anteroposterior approach.

BACKGROUND CONTEXT: Considerable debate exists regarding the optimal surgical approach for adult spinal deformity (ASD). It remains unclear which approach, posterior-only or combined anterior-posterior (AP), is more cost-effective. Our goal is to determine the 2-year cost per quality-adjusted life year (QALY) for each approach. PURPOSE: To compare the 2-year cost-effectiveness of surgical treatment for ASD between the posterior-only approach and combined AP approach. STUDY DESIGN: Retrospective economic analysis of a prospective, multicenter database PATIENT SAMPLE: From a prospective, multicenter surgical database of ASD, patients undergoing five or more level fusions through a posterior-only or AP approach were identified and compared. METHODS: QALYs gained were determined using baseline, 1-year, and 2-year postoperative Short Form 6D. Cost was calculated from actual, direct hospital costs including any subsequent readmission or revision. Cost-effectiveness was determined using cost/QALY gained. RESULTS: The AP approach showed significantly higher index cost than the posterior-only approach ($84,329 vs. $64,281). This margin decreased at 2-year follow-up with total costs of $89,824 and $73,904, respectively. QALYs gained at 2 years were similar with 0.21 and 0.17 in the posterior-only and the AP approaches, respectively. The cost/QALY at 2 years after surgery was significantly higher in the AP approach ($525,080) than in the posterior-only approach ($351,086). CONCLUSIONS: We assessed 2-year cost-effectiveness for the surgical treatment through posterior-only and AP approaches. The posterior-only approach is less expensive both for the index surgery and at 2-year follow-up. The QALY gained at 2-years was similar between the two approaches. Thus, posterior-only approach was more cost-effective than the AP approach under our study parameters. However, both approaches were not cost-effective at 2-year follow-up.

Cost-Utility Analysis of rhBMP-2 Use in Adult Spinal Deformity Surgery.

STUDY DESIGN: Economic modeling of data from a multicenter, prospective registry. OBJECTIVE: The aim of this study was to analyze the cost utility of recombinant human bone morphogenetic protein-2 (BMP) in adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: ASD surgery is expensive and presents risk of major complications. BMP is frequently used off-label to reduce the risk of pseudarthrosis. METHODS: Of 522 ASD patients with fusion of five or more spinal levels, 367 (70%) had at least 2-year follow-up. Total direct cost was calculated by adding direct costs of the index surgery and any subsequent reoperations or readmissions. Cumulative quality-adjusted life years (QALYs) gained were calculated from the change in preoperative to final follow-up SF-6D health utility score. A decision-analysis model comparing BMP versus no-BMP was developed with pseudarthrosis as the primary outcome. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates (Alpha = 0.05). RESULTS: BMP was used in the index surgery for 267 patients (73%). The mean (±standard deviation) direct cost of BMP for the index surgery was $14,000 ±â€Š$6400. Forty patients (11%) underwent revision surgery for symptomatic pseudarthrosis (BMP group, 8.6%; no-BMP group, 17%; P = 0.022). The mean 2-year direct cost was significantly higher for patients with pseudarthrosis ($138,000 ±â€Š$17,000) than for patients without pseudarthrosis ($61,000 ±â€Š$25,000) (P < 0.001). Simulation analysis revealed that BMP was associated with positive incremental utility in 67% of patients and considered favorable at a willingness-to-pay threshold of $150,000/QALY in >52% of patients. CONCLUSION: BMP use was associated with reduction in revisions for symptomatic pseudarthrosis in ASD surgery. Cost-utility analysis suggests that BMP use may be favored in ASD surgery; however, this determination requires further research. LEVEL OF EVIDENCE: 2.

Utilization of Predictive Modeling to Determine Episode of Care Costs and to Accurately Identify Catastrophic Cost Nonwarranty Outlier Patients in Adult Spinal Deformity Surgery: A Step Toward Bundled Payments and Risk Sharing.

STUDY DESIGN: Retrospective review of prospectively-collected, multicenter adult spinal deformity (ASD) database. OBJECTIVE: The aim of this study was to evaluate the rate of patients who accrue catastrophic cost (CC) with ASD surgery utilizing direct, actual costs, and determine the feasibility of predicting these outliers. SUMMARY OF BACKGROUND DATA: Cost outliers or surgeries resulting in CC are a major concern for ASD surgery as some question the sustainability of these surgical treatments. METHODS: Generalized linear regression models were used to explain the determinants of direct costs. Regression tree and random forest models were used to predict which patients would have CC (>$100,000). RESULTS: A total of 210 ASD patients were included (mean age of 59.3 years, 83% women). The mean index episode of care direct cost was $70,766 (SD = $24,422). By 90 days and 2 years following surgery, mean direct costs increased to $74,073 and $77,765, respectively. Within 90 days of the index surgery, 11 (5.2%) patients underwent 13 revisions procedures, and by 2 years, 26 (12.4%) patients had undergone 36 revision procedures. The CC threshold at the index surgery and 90-day and 2-year follow-up time points was exceeded by 11.9%, 14.8%, and 19.1% of patients, respectively. Top predictors of cost included number of levels fused, surgeon, surgical approach, interbody fusion (IBF), and length of hospital stay (LOS). At 90 days and 2 years, a total of 80.6% and 64.0% of variance in direct cost, respectively, was explained in the generalized linear regression models. Predictors of CC were number of fused levels, surgical approach, surgeon, IBF, and LOS. CONCLUSION: The present study demonstrates that direct cost in ASD surgery can be accurately predicted. Collectively, these findings may not only prove useful for bundled care initiatives, but also may provide insight into means to reduce and better predict cost of ASD surgery outside of bundled payment plans. LEVEL OF EVIDENCE: 3.

Serum Cotinine versus Parent Reported Measures of Secondhand Smoke Exposure in Rural Appalachian Children.

BACKGROUND: Secondhand smoke (SHS) exposure in Appalachian children and associated adverse effects is understudied and not well documented. This study assessed the prevalence of SHS exposure in Appalachian children by parental self-report and internal biological measure. METHODS: SHS exposure was determined in children residing in rural Appalachian communities during their participation in the Communities Actively Researching Exposure Study between 2009 and 2013. Parents reported the number of smokers in the household and number of cigarettes smoked/day. Children ages 7-9 provided a serum sample for cotinine analysis. Parent reported measures and child serum cotinine measures of SHS exposure were compared with national and Appalachian-state estimates. Data analysis for the study was done in 2013. RESULTS: Approximately 37% parents reported at least one smoker in the home, yet 50% of children had a detectible level of cotinine in serum. The mean serum cotinine level in children was 0.7 + 1.6 ng/mL. In homes of at least one reported smoker, an average of 20 cigarettes were smoked//day. Compared to 7.6% children, aged 3-19 years, exposed to SHS nationally, 36.6% children in our study were exposed to SHS living in Appalachian counties. IMPLICATIONS: Children living in rural Appalachian counties are significantly exposed to SHS exposure. Parental self-reports of smoking underestimates child exposure to SHS as measured by serum cotinine levels. Developing risk communication messages and implementing culturally appropriate interventions aimed at reducing tobacco dependence in rural Appalachian regions should be explored.

Trends in Chronic Liver Disease-Related Hospitalizations: A Population-Based Study.

OBJECTIVES: In a population-based study, we examined time trends in chronic liver disease (CLD)-related hospitalizations in a large and diverse metroplex. METHODS: We examined all CLD-related inpatient encounters (2000-2015) in Dallas-Fort Worth (DFW) using data from the DFW council collaborative that captures claims data from 97% of all hospitalizations in DFW (10.7 million regional patients). RESULTS: There were 83,539 CLD-related hospitalizations in 48,580 unique patients across 84 hospitals. The age and gender standardized annual rate of CLD-related hospitalization increased from 48.9 per 100,000 in 2000 to 125.7 per 100,000 in 2014. Mean age at hospitalization increased from 54.0 (14.1) to 58.5 (13.5) years; the proportion of CLD patients above 65 years increased from 24.2% to 33.1%. HCV-related hospitalizations plateaued, whereas an increase was seen in hospitalizations related to alcohol (9.1 to 22.7 per 100,000) or fatty liver (1.4 per 100,000 to 19.5 per 100,000). The prevalence of medical comorbidities increased for CLD patients: coronary artery disease (4.8% to 14.3%), obesity (2.8% to 14.6%), chronic kidney disease (2.8% to 18.2%), and diabetes (18.0% to 33.2%). Overall hospitalizations with traditional complications of portal hypertension (ascites, varices, and peritonitis) remained stable over time. However, hospitalization with complications related to infection increased from 54.7% to 66.4%, and renal failure increased by sevenfold (2.7% to 19.5%). CONCLUSIONS: CLD-related hospitalizations have increased twofold over the last decade. Hospitalized CLD patients are older and sicker with multiple chronic conditions. Traditional complications of portal hypertension have been superseded by infection and renal failure, warranting a need to redefine what it means to have decompensated CLD.

Pediatric Stroke Rates Over 17 Years: Report From a Population-Based Study.

We previously published rates of pediatric stroke using our population-based Greater Cincinnati Northern Kentucky Stroke Study (GCNK) for periods July 1993-June 1994 and 1999. We report population-based rates from 2 additional study periods: 2005 and 2010. We identified all pediatric strokes for residents of the GCNK region that occurred in July 1, 1993-June 30, 1994, and calendar years 1999, 2005, and 2010. Stroke cases were ascertained by screening discharge ICD-9 codes, and verified by a physician. Pediatric stroke was defined as stroke in those <20 years of age. Stroke rates by study period, overall, by age and by race, were calculated. Eleven children died within 30 days, yielding an all-cause case fatality rate of 15.7% (95% confidence interval 1.1%, 26.4%) with 3 (27.3%) ischemic, 6 (54.5%) hemorrhagic, and 2 (18.2%) unknown stroke type. The pediatric stroke rate of 4.4 per 100 000 in the GCNK study region has not changed over 17 years.

Impact of Readmissions in Episodic Care of Adult Spinal Deformity: Event-Based Cost Analysis of 695 Consecutive Cases.

BACKGROUND: Readmissions following adult spinal deformity surgical procedures frequently occur, placing a substantial burden on patients and providers. Existing literature on readmission costs, including reason-specific readmission costs, is limited. The purposes of this study were to determine the most expensive reasons for readmission, to assess the impact of reasons and timing on readmission costs, and to estimate the drivers of total costs associated with adult spinal deformity surgical procedures. METHODS: We performed a retrospective review of 695 patients with adult spinal deformity (≥18 years of age) who underwent a corrective spine surgical procedure at a single center from 2005 to 2013. Demographic, surgical, and direct cost data expressed in 2010 dollars for the entire inpatient episode of care were obtained from the hospital administrative database. A multivariable linear regression model with a gamma distribution and log-link function was used to estimate the impact of reasons and timing on readmission costs and to identify the primary drivers of long-term costs. RESULTS: The mean age (and standard deviation) of the patients was 50.6 ± 15.8 years, 589 patients (85%) were women, and 637 patients (92%) were Caucasian. The observed readmission rates were 24% overall (costing $10.1 million), 8.8% for 30 days (costing $3.2 million), and 11.7% for 90 days (costing $4.6 million). The most expensive readmissions and their mean readmission cost were pseudarthrosis ($92,755), infection ($75,172), and proximal junctional kyphosis ($66,713), after adjusting for patient and surgical factors. The mean readmission cost after 2 years was $86,081. Older age (p = 0.001), ≥8 levels fused (p = 0.01), and length of index stay at the hospital (p < 0.0001) were independently associated with higher total cost. Surgical procedures in patients with a thoracic-only curve (p = 0.004) or a double curve (p = 0.05) and a surgical approach that was anterior-only (p < 0.0001) or posterior-only (p = 0.01) were independently associated with lower total costs. CONCLUSIONS: Compared with readmission cost due to medical reasons, readmission due to pseudarthrosis increases mean readmission cost by 105%, readmission due to infection increases mean readmission cost by 72%, and readmission due to proximal junctional kyphosis increases mean readmission cost by 63%. Together, these 3 reasons accounted for 73% of readmission costs. This study identifies potential areas for cost reduction and opportunities for reducing readmission rates. CLINICAL RELEVANCE: Although reducing the 30-day and 90-day readmission rates and costs are important; adult spinal deformity surgery is unique, because the most common and most expensive complications occur after 1 year. We believe that our paper is clinically relevant as it will help to guide clinical focus on the most impactful complications.

Center variation in episode-of-care costs for adult spinal deformity surgery: results from a prospective, multicenter database.

BACKGROUND CONTEXT: Adult spinal deformity (ASD) surgery is associated with significant resource utilization, costing more than $958 million in charges for Medicare patients and more than $1.7 billion in charges for managed care population in the last decade. Given the recent move toward bundled payment models, it is important to understand the various care components a patient receives over the course of a defined clinical episode, its associated cost, and the proportion of cost for each component toward the bundled payment. PURPOSE: To examine the degree and determinants of variation in inpatient episode-of-care (EOC) cost, resource utilization, and patient-reported outcomes for patients undergoing ASD surgery across four spine deformity centers in the United States. STUDY DESIGN/SETTING: Retrospective analysis of prospective, multicenter database. PATIENT SAMPLE: Consecutive patients enrolled in an ASD database from four spinal deformity centers. OUTCOME MEASURES: Total in-patient EOC costs and Short Form (SF)-6D. METHODS: The study used a multicenter database of 210 consecutively enrolled operative patients from 2008 to 2013 at four participating centers in the United States. Demographic, surgical, and direct cost data, expressed in 2013 dollars, for the entire inpatient EOC were obtained from administrative databases from the respective hospitals. Mixed models and multivariable linear regression were used to evaluate the impact of center on total costs adjusting for patient characteristics, length of stay (LOS), and surgical factors. RESULTS: A total of 126 patients with complete baseline and 2-year follow-up data were included. The percentages of patients from each center were 36.5%, 7.1%, 24.6%, and 31.7%. Overall, the mean patient age was 58.4±12.6 years, 86% were women, and 94% were Caucasian. The proportion of total cost variation explained by the center at which the patient was treated was 17%. After adjusting for patient, LOS, and surgical factors the cost variation reduced to 4%. In multivariable analysis, each additional level fused increased total cost variation by $2,500, whereas recombinant human bone morphogenetic protein-2 (BMP) use and posterior-only surgical approach lowered total EOC costs by $10,500 and $9,400, respectively. No significant difference was observed in 2-year quality-adjusted life year across centers. CONCLUSIONS: Total EOC costs for ASD surgery varied significantly by center. Levels fused, BMP use, and surgical approach were the primary drivers of cost variation across centers. Differences in resource utilization had no impact on 2-year quality-adjusted life year improvement across centers.

The effects of hip abduction on sciatic nerve biomechanics during terminal hip flexion.

Terminal hip flexion contributes to increased strain in peripheral nerves at the level of the hip joint. The effects of hip abduction and femoral version on sciatic nerve biomechanics are not well understood. A decrease in sciatic nerve strain will be observed during terminal hip flexion and hip abduction, independent of femoral version. Six un-embalmed human cadavers were utilized. Three Differential Variable Reluctance Transducers (DVRTs) sensors were placed on the sciatic nerve while the leg was flexed to 70° with a combination of - 10°, 0°, 20° and 40° adduction/abduction. DVRT placement included: (i) under piriformis, (ii) immediately distal to the gemelli/obturator, (iii) four centimeters distal to sensor two. A de-rotational osteotomy to decrease femoral version 10° was performed, and sciatic nerve strain was measured by the same procedure. Data were analyzed with three-way analysis of variance and Bonferroni post-hoc analysis to identify differences in the mean values of sciatic nerve strain between native and decreased version state, hip abduction angle and DVRT sensor location. Significant main effects were observed for femoral version (P = 0.04) and DVRT sensor location (P = 0.01). Sciatic nerve strain decreased during terminal hip flexion and abduction in the decreased version state. An 84.23% decrease in sciatic nerve strain was observed during hip abduction from neutral to 40° in the presence of decreased version at terminal hip flexion. The results obtained from this study confirm the role of decreased femoral version and hip abduction at terminal hip flexion to decrease the strain in the sciatic nerve.

Hyperlipidemia is associated with lower risk of poststroke mortality independent of statin use: A population-based study.

Background Although statin therapy is associated with reduced stroke and mortality risk, some studies report that higher lipid levels are associated with improved outcomes following ischemic stroke. Aims We examined the association of hyperlipidemia (HLD) combined with statin therapy on all-cause mortality in stroke patients. Methods All stroke patients in the Greater Cincinnati Northern Kentucky region of ∼1.3 million were identified using ICD-9 discharge codes in 2005 and 2010. Stroke patients with and without HLD were categorized based on their reported statin use at baseline or discharge into three groups: no-HLD/no-statins, HLD/no-statins, and HLD/on-statins. Cox proportional hazards model was used to estimate the risk of mortality at 30 days, 1 year, and 3 years poststroke. Results Overall, 77% (2953) of the 3813 ischemic stroke patients were diagnosed with HLD and 72% ( n = 2123) of those patients were on statin medications. The mean age was 70.0 ± 14.6 years, 56% were women, and 21% were black. In adjusted analyses, the HLD/no-statins group showed 35% (adjusted hazard ratio (aHR) = 0.65, 95% CI: 0.46-0.92), 27% (aHR = 0.73, 95% CI: 0.59-0.90), and 17% (aHR = 0.83, 95% CI: 0.70-0.97) reduced risk of mortality at 30 days, 1 year, and 3 years, respectively, poststroke, compared with no-HLD/no-statins group. The HLD/on-statins group showed an additional 17% significant survival benefit at 3 years poststroke compared with HLD/no-statins group. Conclusions A diagnosis of HLD in ischemic stroke patients is associated with reduced short- and long-term mortality, irrespective of statin use. Statin therapy is associated with significant, additional long-term survival benefit.

Impact of spine surgery complications on costs associated with management of adult spinal deformity.

A better understanding of the consequences of spine surgery complications is warranted to optimize patient-reported outcomes and contain the rising health care costs associated with the management of adult spinal deformity (ASD). We systematically searched PubMed and Scopus databases using keywords "adult spinal deformity surgery," "complications," and "cost" for published studies on costs of complications associated with spinal surgery, with a particular emphasis on ASD and scoliosis. In the 17 articles reviewed, we identified 355,354 patients with 11,148 reported complications. Infection was the most commonly reported complication, with an average treatment cost ranging from $15,817 to $38,701. Hospital costs for patients with deep venous thrombosis, pulmonary thromboembolism, and surgical site infection were 2.3 to 3.1 times greater than for patients without those complications. An effort to collect and characterize data on cost of complications is encouraged, which may help health care providers to identify potential resources to limit complications and overall costs.