[Long-term outcome of EVAHEART I implantable ventricular assist device for the treatment of end stage heart failure: clinical 3-year follow-up results of 15 cases]

Objective: To evaluate the long-term efficacy and safety of the implantable ventricular assist system EVAHEART I in clinical use. Methods: Fifteen consecutive patients with end-stage heart failure who received left ventricular assist device therapy in Fuwai Hospital from January 2018 to December 2021 were enrolled in this study, their clinical data were retrospectively analyzed. Cardiac function, liver and kidney function, New York Heart Association (NYHA) classification, 6-minute walk distance and quality of life were evaluated before implantation and at 1, 6, 12, 24 and 36 months after device implantation. Drive cable infection, hemolysis, cerebrovascular events, mechanical failure, abnormally high-power consumption and abnormal pump flow were recorded during follow up. Results: All 15 patients were male, mean average age was (43.0±7.5) years, including 11 cases of dilated cardiomyopathy, 2 cases of ischemic cardiomyopathy, and 2 cases of valvular heart disease. All patients were hemodynamically stable on more than one intravenous vasoactive drugs, and 3 patients were supported by preoperative intra aortic balloon pump (IABP). Compared with before device implantation, left ventricular end-diastolic dimension (LVEDD) was significantly decreased ((80.93±6.69) mm vs. (63.73±6.31) mm, P<0.05), brain natriuretic peptide (BNP), total bilirubin and creatinine were also significantly decreased ((3 544.85±1 723.77) ng/L vs. (770.80±406.39) ng/L; (21.28±10.51) μmol/L vs. (17.39±7.68) μmol/L; (95.82±34.88) μmol/L vs. (77.32±43.81) μmol/L; P<0.05) at 1 week after device implantation. All patients in this group were in NYHA class Ⅳ before implantation, and 9 patients could recover to NYHA class Ⅲ, 3 to class Ⅱ, and 3 to class Ⅰ at 1 month after operation. All patients recovered to class Ⅰ-Ⅱ at 6 months after operation. The 6-minute walk distance, total quality of life and visual analogue scale were significantly increased and improved at 1 month after implantation compared with those before operation (P<0.05). All patients were implanted with EVAHEART I at speeds between 1 700-1 950 rpm, flow rates between 3.2-4.5 L/min, power consumption of 3-9 W. The 1-year, 2-year, and 3-year survival rates were 100%, 87%, and 80%, respectively. Three patients died of multiple organ failure at 412, 610, and 872 d after surgery, respectively. During long-term device carrying, 3 patients developed drive cable infection on 170, 220, and 475 d after surgery, respectively, and were cured by dressing change. One patient underwent heart transplantation at 155 d after surgery due to bacteremia. Three patients developed transient ischemic attack and 1 patient developed hemorrhagic stroke events, all cured without sequelae. Conclusion: EVAHEART I implantable left heart assist system can effectively treat critically ill patients with end-stage heart failure, can be carried for long-term life and significantly improve the survival rate, with clear clinical efficacy.

[Surgical treatment of heart failure in China: towards the era of artificial heart]

The number of patients with heart failure in China is large, and the proportion of patients with end-stage heart failure continues to increase. The clinical effect of guideline-directed medications therapy for end-stage heart failure is poor. Heart transplantation is the most effective treatment for end-stage heart failure. But it is faced with many limitations such as the shortage of donors. In recent years, the research and development of artificial heart in China has made great progress. Three devices have been approved by the National Medical Products Administration for marketing, and another one is undergoing pre-marketing clinical trial. Since 2017, more than 200 cases of ventricular assist device implantation have been carried out in more than 34 hospitals in China. Among them, 70 patients in Fuwai Hospital, Chinese Academy of Medical Sciences had a 2-year survival rate of 90%. The first patient has survived more than 5 years with the device. More efforts should be put into the training of standardized technical team and quality control. Further research should be carried out in the aspects of pulsatile blood flow pump, fully implanted cable-free device, and improved biomaterial with better blood compatibility.

Impact of Survey Setting on Current Tobacco Product Use: National Youth Tobacco Survey, 2021

PURPOSE

To examine whether survey setting was associated with youth reporting of current (past 30-day) use of any tobacco product, e-cigarettes, cigarettes, and cigars.

METHODS

Data from the 2021 National Youth Tobacco Survey (NYTS) were used to estimate the prevalence of current use of any tobacco product, e-cigarettes, cigarettes, and cigars by survey setting, sociodemographic characteristics, peer tobacco use, and other tobacco product use. Multivariable regression was used to test the impact of survey setting on current tobacco use. Tobacco access sources among current users were compared by survey setting.

RESULTS

Among students who participated in the 2021 NYTS, 50.8% reported taking the survey on school campus and 49.2% at home/other place. The prevalence of current use of any tobacco product, e-cigarettes, cigarettes, and cigars was higher among students completing the survey on school campus than at home/other place. After adjusting for covariates, this association persisted only for current use of any tobacco product (adjusted odds ratio = 1.57; 95% confidence interval, 1.28-1.91) and e-cigarettes (adjusted odds ratio = 1.43; 95% confidence interval, 1.20-1.71). Current users reported similar sources of access to tobacco products, regardless of survey setting.

DISCUSSION

The likelihood of youth reporting current use of any tobacco product and e-cigarettes differed by survey setting. Such differences could be due to lack of privacy at home, peer influence in school settings, and other unmeasured characteristics. Methodological changes were made due to COVID-19; caution is warranted in comparing results from the 2021 NYTS with those of previous or future NYTS conducted primarily on school campus.

Employer requirements and COVID-19 vaccination and attitudes among healthcare personnel in the U.S.: Findings from National Immunization Survey Adult COVID Module, August - September 2021

INTRODUCTION

Employer vaccination requirements have been used to increase vaccination uptake among healthcare personnel (HCP). In summer 2021, HCP were the group most likely to have employer requirements for COVID-19 vaccinations as healthcare facilities led the implementation of such requirements. This study examined the association between employer requirements and HCP's COVID-19 vaccination status and attitudes about the vaccine.

METHODS

Participants were a national representative sample of United States (US) adults who completed the National Immunization Survey Adult COVID Module (NIS-ACM) during August-September 2021. Respondents were asked about COVID-19 vaccination and intent, requirements for vaccination, place of work, attitudes surrounding vaccinations, and sociodemographic variables. This analysis focused on HCP respondents. We first calculated the weighted proportion reporting COVID-19 vaccination for HCP by sociodemographic variables. Then we computed unadjusted and adjusted prevalence ratios for vaccination coverage and key indicators on vaccine attitudes, comparing HCP based on individual self-report of vaccination requirements.

RESULTS

Of 12,875 HCP respondents, 41.5% reported COVID-19 vaccination employer requirements. Among HCP with vaccination requirements, 90.5% had been vaccinated against COVID-19, as compared to 73.3% of HCP without vaccination requirements-a pattern consistent across sociodemographic groups. Notably, the greatest differences in uptake between HCP with and without employee requirements were seen in sociodemographic subgroups with the lowest vaccination uptake, e.g., HCP aged 18-29 years, HCP with high school or less education, HCP living below poverty, and uninsured HCP. In every sociodemographic subgroup examined, vaccine uptake was more equitable among HCP with vaccination requirements than in HCP without. Finally, HCP with vaccination requirements were also more likely to express confidence in the vaccine's safety (68.3% vs. 60.1%) and importance (89.6% vs 79.6%).

CONCLUSION

In a large national US sample, employer requirements were associated with higher and more equitable HCP vaccination uptake across all sociodemographic groups examined. Our findings suggest that employer requirements can contribute to improving COVID-19 vaccination coverage, similar to patterns seen for other vaccines.

Cigarettes, Smokeless Tobacco, and E-Cigarettes: State-Specific Use Patterns Among U.S. Adults, 2017-2018

INTRODUCTION

State-level monitoring of changes in tobacco product use can inform tobacco control policy and practice. This study examines the state-specific prevalence of current cigarette smoking, smokeless tobacco use, and E-cigarette use and related cigarette quitting behaviors among E-cigarette users during 2017-2018.

METHODS

Data from the 2017 and 2018 Behavioral Risk Factor Surveillance System were used to assess state-specific current use of cigarettes, smokeless tobacco, and E-cigarettes among adults aged ≥18 years. Analyzed in 2021, state-specific tobacco product estimates and relative percentage changes between 2017 and 2018 were computed for U.S. states and the District of Columbia. Chi-square tests captured subgroup differences, and logistic regression assessed changes over time.

RESULTS

Prevalence of adult current cigarette smoking and smokeless tobacco use varied across states and remained relatively stable during 2017-2018, whereas the prevalence of adult E-cigarette use significantly increased during 2017-2018 among 19 of 36 states that collected Behavioral Risk Factor Surveillance System E-cigarette data in 2018. In all states and the District of Columbia during 2017-2018 combined, the percentage of current cigarette smoking among current E-cigarette users was higher than that of never cigarette smoking; the percentage of attempting to quit cigarette smoking in the past year among dual users of cigarettes and E-cigarettes was >50%.

CONCLUSIONS

During 2017-2018, the prevalence of adult current cigarette smoking and smokeless tobacco use varied across states and remained relatively stable, whereas adult E-cigarette use prevalence significantly increased. Comprehensive state-based tobacco prevention and control efforts are warranted to reduce the morbidity and mortality attributed to the use of all tobacco products, including E-cigarettes, among U.S. adults.

[Clinicopathological features and gene phenotypes of benign metastasizing leiomyoma]

Objective: To study the clinicopathological features, immunophenotypes and MED12 gene status in benign metastasizing leiomyoma (BML). Methods: Nine cases of BML diagnosed at the Affiliated Hospital of Qingdao University from 2012 to 2018 were collected, and the radiologic and histologic features were analyzed. The protein expression of leiomyosarcoma-related driver genes, including RB1, PTEN,ATRX,p16,p53, as well as ER,PR,CD34,FH, and Ki-67 were detected using immunohistochemistry, and the mutation status of MED12 gene exon 2 was detected by Sanger sequencing. Results: All the nine patients with BML were female, and the age range was 48 to 64 years (median 55 years). All patients had history of uterine fibroids. The morphologic features of BML were similar to a benign uterine leiomyoma and did not exhibit malignant characteristics. All cases were positive for ER and PR, and negative for CD34. In addition, RB1, PTEN, ATRX, and FH were positive in all cases (wild type), while p16 showed a focally positive pattern. P53 positive index was less than 5% (wild type), and Ki-67 positive index was less than 1%. Sanger sequencing was done in six BML samples; one sample harbored a nonsense mutation c. 142_144delinsTAA (p.Glu48Ter), and another exhibited a synonymy mutation (c.192C>T, p.Phe64=)and one missense mutation c.196C>T (p.Pro66Ser). Conclusions: The present study suggests that BML is a unique leiomyoma entity that is pathologically and genetically different from leiomyosarcomas and conventional uterine leiomyomas. Evaluating the genetic phenotype of BML, especially the expression of leiomyosarcoma-related driver genes protein and MED12 gene status, may be helpful in understanding the pathogenesis of BML and in its differentiation from leiomyosarcoma.

Feasibility of Administering an Electronic Version of the National Youth Tobacco Survey in a Classroom Setting

Introduction

The National Youth Tobacco Survey (NYTS) has successfully monitored tobacco product use patterns and correlates since 1999 among US students in grades 6 through 12 using a scannable paper-and-pencil format. We conducted a study to determine the feasibility and potential benefits of administering an electronic version of the NYTS in school settings.

Methods

The pilot survey was administered by using 2 versions. Version 1 mimicked the scannable paper-and-pencil format with respect to design, formatting, and structure, but was administered on a tablet computer. Version 2 used an electronic survey design and formatting capabilities, which included programmed logic skips and tobacco product images. Chi-square and t tests were used to assess subgroup differences. Multivariable-adjusted logistic regression models were used to determine if the odds of ever and current tobacco product use differed between the 2 versions.

Results

In total, 2,769 students completed version 1 or version 2. Three-quarters of respondents reported a strong preference for using an electronic device to take the NYTS (74.7%). Compared with version 1, version 2 reduced the mean time to complete the survey by 15% (P < .01), reduced the number of questions students needed to answer by 30% (P < .01), and removed 1.9% of inconsistent survey responses. A significant difference was observed for ever e-cigarette use between versions 1 (22.2%) and 2 (29.5%; P < .0001). No significant differences in ever or current use were observed for other tobacco products.

Conclusion

An electronic mode of administration is feasible and valid for conducting surveillance of tobacco product use among US youths.

Tobacco-Free Pharmacies and U.S. Adult Smoking Behavior: Evidence From CVS Health's Removal of Tobacco Sales

INTRODUCTION

Beginning September 3, 2014, CVS Health stopped selling tobacco products in all of its retail stores nationwide. This study assessed the impact of removing tobacco sales from CVS Health on cigarette smoking behaviors among U.S. adult smokers.

METHODS

CVS Health retail location data (2012-2016) were linked with data from the Behavioral Risk Factor Surveillance System, a phone-based survey of the non-institutionalized civilian population aged ≥18 years. Using a difference-in-differences regression model, quit attempts and daily versus nondaily smoking were compared between smokers living in counties with CVS stores and counties without CVS stores, before and after CVS's removal of tobacco sales. Control variables included individuals' sociodemographic and health-related variables, state tobacco control variables, and urban status of counties. Analyses were conducted in 2018.

RESULTS

During the 2-year period following the removal of tobacco sales from CVS Health, smokers living in counties with high CVS density (≥3.5 CVS stores per 100,000 people) had a 2.21% (95% CI=0.08, 4.33) increase in their quit attempt rates compared with smokers living in counties without CVS stores. This effect was greater in urban areas (marginal effect: 3.03%, 95% CI=0.81, 5.25); however, there was no statistically significant impact in rural areas. Additionally, there was no impact on daily versus nondaily smoking in either urban or rural areas.

CONCLUSIONS

Removing tobacco sales in retail pharmacies could help support cessation among U.S. adults who are attempting to quit smoking, particularly in urban areas.

[Association of platelet/lymphocyte ratio and neutrophil/lymphocyte ratio with protein-energy wasting in maintenance hemodialysis patients]

Objective: To explore the association of platelet/lymphocyte ratio (PLR) and neutrophil/lymphocyte ratio (NLR) with protein energy wasting (PEW) in maintenance hemodialysis (MHD) patients. Methods: A multicenter cross-sectional study was conducted in eleven hemodialysis centers of Guizhou province from June to August, 2017. Clinical data, physical parameters, body composition data and laboratory values of MHD patients were collected. PLR and NLR were calculated according to routine blood test. All patients were divided into four groups (Q1-Q4) according to the median and quartile of PLR and NLR. Multivariate logistic regression models were applied to analyze the relationships between PLR, NLR and PEW. The comparison of predictive power of PLR and NLR for PEW was evaluated by receiver operating characteristic curve (ROC). Results: A total of 936 MHD patients were enrolled (519 males, 417 females), with a mean age of (55.6±15.6) years. The prevalence of PEW was 46.2% (432/936). Multivariate logistic regression analysis showed that patients in group PLR Q3 and Q4 were 2.07 (95%CI: 1.03-4.13, P=0.014) and 2.73 (95%CI: 1.58-4.74, P<0.001) times more likely to have PEW, compared with those in group PLR Q1 in unadjusted models. PLR was significantly associated with the development of PEW after adjusting age, sex, history of hypertension, diabetes and hemoglobin. Patients in Group PLR Q3 and Q4 were 2.82 times (95%CI: 1.42-5.60, P=0.003) and 2.93 times (95%CI: 1.50-5.73, P=0.002) times more likely to have PEW than those in Group PLR Q1. The ROC showed that only PLR can predict the development of PEW with a diagnostic threshold of 144.09 [area under curve (AUC)=0.61, 95%CI: 0.56-0.66, P<0.001], with a sensitivity and specificity of 61% and 58%, respectively, while the AUC of NLR is 0.55 (P=0.091). Conclusion: For MHD patients, only PLR could be a relevent factor of PEW and it showed the predictive power of PEW rather than NLR.

State-Specific Patterns of Cigarette Smoking, Smokeless Tobacco Use, and E-Cigarette Use Among Adults - United States, 2016

Introduction

State-level monitoring of changes in tobacco product use can help inform tobacco control policy and practice. This study examined state-specific prevalence of cigarette, smokeless tobacco, and e-cigarette use among US adults.

Methods

Data came from the 2016 Behavioral Risk Factor Surveillance System (BRFSS), a state-based telephone survey of US adults aged 18 years or older (N = 477,665). Prevalence estimates for current (every day or some days) cigarette smoking, smokeless tobacco use, and e-cigarette use were calculated for all 50 states and the District of Columbia (DC) and stratified by sex and race/ethnicity. Because the 2016 BRFSS measured e-cigarette use for the first time, estimates of ever e-cigarette use and concurrent use of cigarettes and e-cigarettes were also calculated. We assessed subgroup differences with χ² tests.

Results

In 2016, prevalence of current cigarette smoking among US adults ranged from 8.8% (Utah) to 24.8% (West Virginia), while prevalence of current smokeless tobacco use ranged from 1.3% (DC) to 9.8% (Wyoming). For e-cigarettes, ever use ranged from 16.2% (DC) to 28.4% (Arkansas), and current use ranged from 2.4% (DC) to 6.7% (Oklahoma). Across all states, current e-cigarette use was significantly higher among current cigarette smokers than among former or never cigarette smokers. States with the highest prevalence of cigarette smoking generally had a high prevalence of current e-cigarette use.

Conclusion

Prevalence of adult cigarette smoking, smokeless tobacco use, and e-cigarette use varies across states. These findings underscore the importance of comprehensive statewide tobacco control and use prevention efforts that address the diverse tobacco products used among adults.

[Association of low serum parathyroid hormone with protein-energy wasting in maintenance hemodialysis patients]

Objective: To examine the relationship between low serum parathyroid hormone (PTH) and protein-energy wasting (PEW) in patients who underwent maintenance hemodialysis (MHD) treatment. Methods: A cross-sectional study was conducted in MHD patients between June 2015 and August 2017 in 11 MHD centers from Guizhou province. Body composition and physical parameters were measured, clinical data and other related laboratory values were collected according to the medical record system. Participants were assigned to low serum PTH group (PTH<150 ng/L), target PTH group (150 ng/L≤ PTH ≤300 ng/L) and high serum PTH group (PTH>300 ng/L). Multivariate logistic regression analysis was used to analyze the relationship between low serum PTH and risk of PEW, which was diagnosed according to the diagnostic criteria recommened by the International Society of Renal Nutrition and Metabolism (ISRNM). Results: A total of 873 MHD patients (488 males and 385 females) were included in the final analysis, with a mean age of 55.0 (44.0, 67.0) years and a mean hemodialysis duration of 31.0(17.0, 54.0) months. In unadjusted model, low serum PTH group was associated with PEW (OR=2.12, 95% CI: 1.26-3.54, P=0.004), when compared with high serum PTH group. After adjustment for age and sex, low serum PTH group was still significantly associated with PEW (OR=2.09, 95% CI: 1.23-3.52, P=0.006). Further adjustment for diabetes and hypertension, the correlation between low serum PTH group and PEW was still significant (OR=2.02, 95% CI: 1.04-3.90, P=0.037). However, the correlation was not observed in target PTH group and high serum PTH group. Conclusion: Low serum PTH was associated with risk of PEW, regardless of age, sex, history of diabetes and hypertension, and thus it might be a promising indicator of PEW in MHD patients.

[Interventional treatment of symptomatic intracranial in-stent restenosis]

Objective: To assess the feasibility and safety of interventional treatment of symptomatic intracranial in-stent restenosis (SISR). Methods: Clinical data of 21 patients with SISR who underwent interventional treatment in the General Hospital of the PLA Rocket Force from January 2012 to May 2018 were retrospectively analyzed. Perioperative complications, angiographic and clinical follow-up results were recorded. Results: The success rate of treatment was 100%, including 21 lesions of SISR (7 at the V4 segment of the vertebral artery, 7 at the basilar artery, 5 at the M1 segment of middle cerebral artery, 2 at the internal carotid artery). The residual stenosis rate was preoperative 84±7, postoperative 30±14 respectively. Balloon angioplasty and stent implantation were performed in 10 patients (48.6%) and 11 patients (52.4%), respectively. After treatment, 1 patient experienced perforating event without neurological sequelae. Of the 11 patients (52.4%) completed angiography follow-up, 3 (3/11, 27.3%) ocurred restenosis and 1 was retreated. During clinical follow-up, 1 patients received intravenous thrombolysis for the symptom of acute cerebral infarction in territory of stenting artery, in-stent restenosis or occlusion was not demonstrated by emergency cerebral angiography. Conclusion: Interventional treatment of SISR is feasible and safe, however, further studies need to warrant the long-term effects.

[Application of the descending branch of the lateral circumflex femoral artery in the coronary artery bypass grafting operation]

Objective: To investigate the technical method for harvesting and application of the descending branch of the lateral circumflex femoral artery (DBLCFA) in the coronary artery bypass grafting (CABG) operation. Methods: Between December 2016 and April 2017, 19 patients were arranged to use DBLCFA and got CT angiography (CTA) of pelvic and femoral arteries pre-operative at Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Finally, DBLCFA was harvested in 16 patients (including 2 female patients, with a mean age of (47.4±8.5) years) through the anterior thigh incision (13 cases on the left side, 3 cases on the right side). The CABG operations were performed under the cardiopulmonary bypass support (in 10 cases) or under the beating heart condition (in 6 cases), and the DBLCFA conduit was used combining with bilateral internal thoracic artery (in 12 cases), radial artery (in 7 cases) and saphenpous vein (in 3 cases). Results: Due to anatomical variations such as short length and anomalous branch, or due to silent atherosclerosis stenosis of femoral artery, DBLCFA in 3 patients was considered inappropriate for use and was not harvested after CTA examination. In another 16 patients, DBLCFA was safely and quickly harvested and successfully used. On average, 3.4±0.6 anastomosis was built up in CBAG, no adverse effects were exhibited. The length of the harvested DBLCFA was (10.3±1.8) cm, with average lumen diameter of (1.9±0.5) mm. DBLCFA was used as free graft in 15 patients (7 to the first diagonal branch, 6 to the ramus intermedius branch, 1 to the left anterior descending branch and 1 to the second obtuse marginal branch). In 1 patient, the DBLCFA was firstly implanted end-to-side to the internal thoracic artery as a "Y" type composite graft, and then anastomosed to the third obtuse marginal branch. Conclusions: The descending branch of the lateral circumflex femoral artery is an option conduit in CABG. It can be harvested easily and safely. However, pre-operative CTA examination is necessary to exclude the variation and appropriate strategy for graft establishment should be considered during the operation.

Tobacco Product Use Among Adults - United States, 2013-2014

While significant declines in cigarette smoking have occurred among U.S. adults during the past 5 decades, the use of emerging tobacco products* has increased in recent years (1-3). To estimate tobacco use among U.S. adults aged ≥18 years, CDC and the Food and Drug Administration (FDA) analyzed data from the 2013-2014 National Adult Tobacco Survey (NATS). During 2013-2014, 21.3% of U.S. adults used a tobacco product every day or some days, and 25.5% of U.S. adults used a tobacco product every day, some days, or rarely. Despite progress in reducing cigarette smoking, during 2013-2014, cigarettes remained the most commonly used tobacco product among adults. Young adults aged 18-24 years reported the highest prevalence of use of emerging tobacco products, including water pipes/hookahs and electronic cigarettes (e-cigarettes). Furthermore, racial/ethnic and sociodemographic differences in the use of any tobacco product were observed, with higher use reported among males; non-Hispanic whites, non-Hispanic blacks, and non-Hispanics of other races(†); persons aged <45 years; persons living in the Midwest or South; persons with a General Educational Development (GED) certificate; persons who were single/never married/not living with a partner or divorced/separated/widowed; persons with annual household income <$20,000; and persons who were lesbian, gay, or bisexual (LGB). Population-level interventions that focus on all forms of tobacco product use, including tobacco price increases, high-impact anti-tobacco mass media campaigns, comprehensive smoke-free laws, and enhanced access to help quitting tobacco use, in conjunction with FDA regulation of tobacco products, are critical to reducing tobacco-related diseases and deaths in the United States.(§).

Current cigarette smoking among adults - United States, 2005-2014

Tobacco smoking is the leading cause of preventable disease and death in the United States, resulting in approximately 480,000 premature deaths and more than $300 billion in direct health care expenditures and productivity losses each year (1). To assess progress toward achieving the Healthy People 2020 objective of reducing the percentage of U.S. adults who smoke cigarettes to ≤12.0%,* CDC assessed the most recent national estimates of smoking prevalence among adults aged ≥18 years using data from the 2014 National Health Interview Survey (NHIS). The percentage of U.S. adults who smoke cigarettes declined from 20.9% in 2005 to 16.8% in 2014. Among daily cigarette smokers, declines were observed in the percentage who smoked 20–29 cigarettes per day (from 34.9% to 27.4%) or ≥30 cigarettes per day (from 12.7% to 6.9%). In 2014, prevalence of cigarette smoking was higher among males, adults aged 25–44 years, multiracial persons and American Indian/Alaska Natives, persons who have a General Education Development certificate, live below the federal poverty level, live in the Midwest, are insured through Medicaid or are uninsured, have a disability or limitation, or are lesbian, gay, or bisexual. Proven population-based interventions, including tobacco price increases, comprehensive smoke-free laws, high impact mass media campaigns, and barrier-free access to quitting assistance, are critical to reduce cigarette smoking and smoking-related disease and death among U.S. adults.

Tobacco product use among adults--United States, 2012-2013

Despite significant declines in cigarette smoking among U.S. adults over the past five decades, progress has slowed in recent years, and the prevalence of use of other tobacco products such as cigars and smokeless tobacco has not changed. Additionally, the prevalence of use of emerging products, including electronic cigarettes (e-cigarettes), has rapidly increased. This report provides the most recent national estimates of tobacco use among adults aged ≥18 years, using data from the 2012-2013 National Adult Tobacco Survey (NATS). The findings indicate that 21.3% of U.S. adults used a tobacco product every day or some days, and 25.2% used a tobacco product every day, some days, or rarely. Population-level interventions focused on the diversity of tobacco product use, including tobacco price increases, high-impact antitobacco mass media campaigns, comprehensive smoke-free laws, and enhanced access to help quitting, in conjunction with Food and Drug Administration (FDA) regulation of tobacco products, are critical to reducing tobacco-related diseases and deaths in the United States.

Expression of immediate-early genes in the inferior colliculus and auditory cortex in salicylate-induced tinnitus in rat

Tinnitus could be associated with neuronal hyperactivity in the auditory center. As a neuronal activity marker, immediate-early gene (IEG) expression is considered part of a general neuronal response to natural stimuli. Some IEGs, especially the activity-dependent cytoskeletal protein (Arc) and the early growth response gene-1 (Egr-1), appear to be highly correlated with sensory-evoked neuronal activity. We hypothesize, therefore, an increase of Arc and Egr-1 will be observed in a tinnitus model. In our study, we used the gap prepulse inhibition of acoustic startle (GPIAS) paradigm to confirm that salicylate induces tinnitus-like behavior in rats. However, expression of the Arc gene and Egr-1 gene were decreased in the inferior colliculus (IC) and auditory cortex (AC), in contradiction of our hypothesis. Expression of N-methyl d-aspartate receptor subunit 2B (NR2B) was increased and all of these changes returned to normal 14 days after treatment with salicylate ceased. These data revealed long-time administration of salicylate induced tinnitus markedly but reversibly and caused neural plasticity changes in the IC and the AC. Decreased expression of Arc and Egr-1 might be involved with instability of synaptic plasticity in tinnitus.

COX-2 and fatty acid amide hydrolase can regulate the time course of depolarization-induced suppression of excitation

BACKGROUND AND PURPOSE

Depolarization-induced suppression of inhibition (DSI) and excitation (DSE) are two forms of cannabinoid CB(1) receptor-mediated inhibition of synaptic transmission, whose durations are regulated by endocannabinoid (eCB) degradation. We have recently shown that in cultured hippocampal neurons monoacylglycerol lipase (MGL) controls the duration of DSE, while DSI duration is determined by both MGL and COX-2. This latter result suggests that DSE might be attenuated, and excitatory transmission enhanced, during inflammation and in other settings where COX-2 expression is up-regulated.

EXPERIMENTAL APPROACH

To investigate whether it is possible to control the duration of eCB-mediated synaptic plasticity by varied expression of eCB-degrading enzymes, we transfected excitatory autaptic hippocampal neurons with putative 2-AG metabolizing enzymes: COX-2, fatty acid amide hydrolase (FAAH), α/β hydrolase domain 6 (ABHD6), α/β hydrolase domain 12 (ABHD12) or MGL.

KEY RESULTS

We found that overexpression of either COX-2 or FAAH shortens the duration of DSE while ABHD6 or ABHD12 do not. In contrast, genetic deletion (MGL(-/-)) and overexpression of MGL both radically altered eCB-mediated synaptic plasticity.

CONCLUSIONS AND IMPLICATIONS

We conclude that both FAAH and COX-2 can be trafficked to neuronal sites where they are able to degrade eCBs to modulate DSE duration and, by extension, net endocannabinoid signalling at a given synapse. The results for COX-2, which is often up-regulated under pathological conditions, are of particular note in that they offer a mechanism by which up-regulated COX-2 may promote neuronal excitation by suppressing DSE while enhancing conversion of 2-AG to PGE(2) -glycerol ester under pathological conditions.

Improving public health surveillance using a dual-frame survey of landline and cell phone numbers

To meet challenges arising from increasing rates of noncoverage in US landline-based telephone samples due to cell-phone-only households, the Behavioral Risk Factor Surveillance System (BRFSS) expanded a traditional landline-based random digit dialing survey to a dual-frame survey of landline and cell phone numbers. In 2008, a survey of adults with cell phones only was conducted in parallel with an ongoing landline-based health survey in 18 states. The authors used the optimal approach to allocate samples into landline and cell-phone-only strata and used a new approach to weighting state-level landline and cell phone samples. They developed logistic models for each of 16 health indicators to examine whether exclusion of adults with cell phones only affected estimates after adjustment for demographic characteristics. The extents of the potential biases in landline telephone surveys that exclude cell phones were estimated. Biases resulting from exclusion of adults with cell phones only from the landline-based survey were found for 9 out of the 16 health indicators. Because landline noncoverage rates for adults with cell phones only continue to increase, these biases are likely to increase. Use of a dual-frame survey of landline and cell phone numbers assisted the BRFSS efforts in obtaining valid, reliable, and representative data.

A modified cannulating technique for the BVS5000

The aim of this study was to report on a modified cannulating method for the BVS5000 left ventricular assist device. From April 2005 to April 2006, a BVS5000 device was implanted using a modified cannulating method in 7 postcardiotomy male patients after coronary artery bypass grafting for left ventricular support. The inflow cannula was inserted into the left atrial artery through a segment of bovine jugular vein and the arterial cannula into the femoral artery. Five patients were successfully weaned from the BVS5000 after recovery of heart function and were discharged from hospital. The BVS5000 was explanted using a minimally invasive technique. The weaning procedure was completed bedside in the intensive care unit under local anesthesia; resternotomy was not necessary. The modified technique is a simpler, safer and more minimally invasive method for selected patients supported by the BVS5000.

[Research on development of gold immunochromagraphic assay test kit for serum Coxsackievirus IgM antibody.]

BACKGROUND

To develop gold immunochromatographic assay (GICA) test kit for serum Coxsackievirus IgM antibody and optimize the key experiment conditions.

METHODS

Colloidal gold particles of 20 nm were prepared and coupled with sheep anti-human IgM, the gold immunochromatography assay test kit was setup for serum Coxsackievirus IgM antibody.

RESULTS

The spheroidal colloid gold particles of 20 nm showed bright red in color. The minimal stable concentration (MSC) of gold sheep anti-human IgM was 1 ug/ml, and the suitable stable concentration (SSC) was 1.5 ug/ml. The pH 8.2 was appropriate; 30 sera samples were tested by GICA and ELISA, there was no significant difference between the two methods.

CONCLUSION

The quality of gold immunochromatography assay test kit is associated with such factors as the quality and quantity of antigen or antibody, colloid gold particles, buffers, etc.

Parametric finite element analysis of vertebral bodies affected by tumors

The vertebral column is the most frequent site of metastatic involvement of the skeleton. Due to the proximity to the spinal cord, from 5% to 10% of all cancer patients develop neurologic manifestations. As a consequence, fracture risk prediction has significant clinical importance. In this study, we model the metastatically involved vertebra so as to parametrically investigate the effects of tumor size, material properties and compressive loading rate on vertebral strength. A two-dimensional axisymmetric finite element model of a spinal motion segment consisting of the first lumbar vertebral body (no posterior elements) and adjacent intervertebral disc was developed to allow the inclusion of a centrally located tumor in the vertebral body. After evaluating elastic, mixed, and poroelastic formulations, we concluded that the poroelastic representation was most suitable for modeling the metastatically involved vertebra's response to compressive load. Maximum principal strains were used to localize regions of potential vertebral trabecular bone failure. Radial and axial vertebral body displacements were used as relative indicators of spinal canal encroachment and endplate failure. Increased tumor size and loading rate, and reduced trabecular bone density all elevated axial and radial displacements and maximum tensile strains. The results of this parametric study suggest that vertebral tumor size and bone density contribute significantly to a patients risk for vertebral fracture and should be incorporated in clinical assessment paradigms.

Magnetic resonance imaging measurement of relaxation and water diffusion in the human lumbar intervertebral disc under compression in vitro

STUDY DESIGN

Twelve lumbar intervertebral disc specimens were imaged with magnetic resonance imaging to estimate relaxation constants, T1 and T2, and tissue water diffusion, before and after applying compression.

OBJECTIVES

The objectives of the study were to measure T1, T2, and water diffusion for differences with loading state, region of the disc (anulus fibrosus or nucleus pulposus), and grade of degeneration.

SUMMARY OF BACKGROUND DATA

Magnetic resonance imaging can be used qualitatively to estimate water content and degeneration of the intervertebral disc. Beyond structural information of images, the relaxation times T1 and T2 may contain information on the changes occurring with degeneration. A modified spin-echo sequence can be used to estimate tissue water diffusion in cartilage and disc specimens with the ability to measure anisotropy.

METHODS

Specimens were imaged in a 1.5-Tesla clinical scanner. T1, T2, and water diffusion were estimated from midsagittal images. Magnetic resonance imaging parameters were calculated before and after axial loading. The measured T1, T2, and D (diffusion coefficient) were compared before and after compression, and for the diffusion data, also by direction to consider anisotropy.

RESULTS

For the T1 data, a significant difference was found by region, nucleus > anulus, and loading state, loaded > unloaded. For the T2 values, there was a significant difference by region, nucleus > anulus, and Thompson grade. For diffusion, significant differences were found by region, nucleus > anulus, Thompson grade, direction of diffusion, and state of compression, loaded > unloaded.

CONCLUSIONS

This study demonstrated that magnetic resonance imaging can be used to measure significant changes in T1, T2, or diffusion in intervertebral disc specimens by region, loading condition, or Thompson grade.

Management of fixed sagittal plane deformity: results of the transpedicular wedge resection osteotomy

STUDY DESIGN

Retrospective review of a consecutive clinical series.

OBJECTIVES

To evaluate the efficacy of the transpedicular wedge resection osteotomy as a technique for correction of sagittal and coronal deformity and to assess the clinical value of the procedure as assessed by patient satisfaction.

SUMMARY OF BACKGROUND DATA

The transpedicular wedge resection osteotomy is a well-established procedure for management of fixed sagittal deformity in ankylosing spondylitis. The utility of the procedure for applications in fixed deformity other than ankylosing spondylitis has not been demonstrated, and the efficacy of the procedure in the correction of coronal deformity has not been reported.

METHODS

A total of 13 consecutive cases undergoing transpedicular wedge resection osteotomy for the management of sagittal deformity of any etiology were reviewed. Radiographic studies, complications, and satisfaction assessment using the modified Scoliosis Research Society instrument were the outcome parameters measured.

RESULTS

Etiologies of deformity included postsurgical, ankylosing spondylitis, idiopathic, and infectious. Measurement of C7 sagittal plumb line to sacrum improved 63% at the most recent follow-up. Lumbar lordosis increased from -15.5 degrees to -45.4 degrees. Coronal balance was improved in all patients who had preoperative imbalance, with an average improvement of 60% maintained at follow-up. Patient satisfaction was high in all patients and not dependent on the etiology of deformity.

CONCLUSIONS

The transpedicular wedge resection osteotomy is an effective procedure for the management of fixed sagittal deformity and is generalizable for multiple etiologies. Simultaneous correction of coronal deformity is possible. The clinical value of the procedure is demonstrated in high rates of patient satisfaction.

Excision of hemivertebrae in the management of congenital scoliosis involving the thoracic and thoracolumbar spine

We present a study of ten consecutive patients who underwent excision of thoracic or thoracolumbar hemivertebrae for either angular deformity in the coronal plane, or both coronal and sagittal deformity. Vertebral excision was carried out anteriorly alone in two patients. Seven patients had undergone previous posterior spinal fusion. Their mean age at surgery was 13.4 years (6 to 19). The mean follow-up was 78.5 months (20 to 180). The results were evaluated by radiological review of the preoperative, postoperative and most recent follow-up films. The mean preoperative coronal curve was 78.2 degrees (30 to 115) and was corrected to 33.9 degrees (7 to 58) postoperatively, a mean correction of 59%. Preoperative coronal decompensation of 35 mm was improved to 11 mm postoperatively. Seven patients had significant coronal decompensation preoperatively, which was corrected to a physiological range postoperatively. There were no major complications and no neurological damage. We have shown that resection of thoracic and thoracolumbar hemivertebrae can be performed safely, without undue risk of neurological compromise, in experienced hands.

[A study on cellular matrix via cell extraction from bovine pericardium]

OBJECTIVE

To obtain an acellular matrix from bovine pericardial tissue, as a scaffold for tissue engineering of heart valves or cardiovascular patching applications.

METHODS

A four step detergent and enzyme link extraction procedure was practiced in this study. The mechanic properties of the acellular matrix were evaluated, and the components were analyzed biochemically.

RESULTS

HE staining confirmed the removal of cells and Von Gieson staining showed the integrality of collagen and elastin. Biochemical analysis demonstrated the retention of collagen and some glycosaminoglycans while the percentage of the soluble proteins reduced slightly. The tissue fracture strength and shrinkage temperature made no significant difference after extraction.

CONCLUSIONS

The extraction process is effective to remove cells from bovine pericardial tissue while maintains its mechanical strength. This approach may eventually lead to a scaffold for heart valves and cardiovascular patching applications in tissue engineering.

Anterior and posterior allografts in symptomatic thoracolumbar deformity

The radiographic and clinical results of 105 patients with symptomatic spinal deformities were categorized retrospectively based on surgical approach and type of bone autograft or allograft used for each patient's fusion surgery into seven different groups and compared with one another. The three bone autograft control groups were posterior autograft only (n = 20), anterior autograft only (n = 6), and combined anterior and posterior autograft (n = 12). The allograft groups were posterior morcellized allograft (n = 7), posterior morcellized allograft and anterior autograft (n = 11), anterior structural interbody allografts and posterior mixture of allograft and autograft (n = 37), and anterior strut allograft with posterior mixture of allograft and autograft (n = 12). Radiographs revealed high pseudoarthrosis rates for adults with a posterior-only allograft and with anterior strut allografts spanning four or more levels. Results of the self-assessment outcomes questionnaire, at a mean follow-up period of 52 months, revealed less pain and improved cosmesis for all groups, and improved function in patients who had undergone combined anteroposterior fusion. The authors conclude that posterior cancellous allograft is a poor substitute for autograft bone and that strut allografts spanning more than four levels require technique modifications to enhance their effectiveness. In general, anterior structural allografts are effective in maintaining correction, result in fusion rates comparable to those of autografts, and correlate to improved outcomes.

Biphasic material properties of lytic bone metastases

It is necessary to prescribe the mechanical properties of tumor tissue when modeling the metastatically involved skeleton for clarifying the mechanisms of fracture. This study provides mechanical property data for lytic bone metastases. Specimens of human lytic tumor were tested under a confined compression uniaxial creep protocol and the mechanical behavior of the tumor tissue was modeled using linear biphasic theory. The tumor tissue was found to have an aggregate modulus (HA) of 3.6 +/- 1.6 kPa and a hydraulic permeability (k) of 0.59 +/- 0.46mm4 N(-1) s(-1). Tumors with a higher percentage of stromal content were found to be stiffer and more permeable than those with a more cellular composition. No significant differences in aggregate modulus or hydraulic permeability were found between lytic metastases of different types. These data are useful for the development of models to simulate the behavior of the metastatically involved skeleton using theoretical or finite-element analysis techniques and also have significance for developing effective tumor-drug-transport models. We anticipate that specification of the mechanical behavior of this tissue may help to better focus future treatment of lytic bony metastases through better assessment of fracture risk and improved drug delivery.

Computer-assisted analysis of radial symmetry in human airway epithelial cilia: assessment of congenital ciliary defects in primary ciliary dyskinesia

The ultrastructural analysis of cilia and diagnosis of primary ciliary dyskinesia (PCD) in biopsies of airway epithelium is sometimes confounded by poor sampling, inconsistencies in tissue quality and processing, and other technical problems. Although clinical findings may lead to a presumptive diagnosis, ultrastructural analysis of ciliary axonemes is the standard for confirmation of PCD. The ultrastructural features of the cilium when viewed in cross section by transmission electron microscopy confer a radial symmetry to the axoneme. Current digital image processing techniques can be applied to such images to reinforce signal, diminish noise, and confirm consistency of position of axonemal structures, a process that can augment ultrastructural analysis for PCD. In this study, computer-assisted digital image processing was used to evaluate cross sections of cilia in airway epithelial biopsies from patients previously diagnosed with PCD as well as in control subjects with normal cilia. These studies supported the original diagnoses and provided some new insights into axonemal organization in PCD. This technique is simple and may be useful in providing a supporting means for confirming or ruling out a diagnosis of PCD in cases that appear equivocal.

Eikenella corrodens vertebral osteomyelitis secondary to direct inoculation: a case report

STUDY DESIGN

A case report.

OBJECTIVE

To present a unique method of inoculation with an unusual bacterial organism, Eikenella corrodens, which led to vertebral osteomyelitis and to heighten awareness of different bacterial organisms that may cause orthopedic infections.

SUMMARY OF BACKGROUND DATA

E. corrodens has been known to cause orthopedic infections for more than 20 years. The usual mechanism is from "Fight bite" injuries to the hand or metacarpal phalangeal joint. Eikenella osteomyelitis of the vertebral body is extremely rare.

METHODS

A 65-year-old man from Indonesia developed slowly progressive vertebral collapse and worsening neck pain. History suggested a previous pharyngeal injury while eating fish. Work up for malignancy was negative, and imaging studies were suggestive of osteomyelitis. An open biopsy and culture as well as fusion were performed for treatment of the osteomyelitis.

RESULTS

After a complete work up was undertaken, cultures grew out E. corrodens as the causative organism of this patient's osteomyelitis. Computed tomography scan and history were consistent with inoculation of the paravertebral space with E. corrodens secondary to a fish bone transgressing the patient's pharynx. The patient was treated with surgery and the appropriate antibiotics and healed without any significant sequela.

CONCLUSION

Vertebral osteomyelitis due to E. corrodens is extremely rare. Direct inoculation as a cause of vertebral osteomyelitis with Eikenella has never been reported. If diagnosed properly with appropriate cultures and antibiotic sensitivities, Eikenella osteomyelitis can be treated successfully according to standard orthopedic practices including debridement, fusion, and appropriate antibiotics. Awareness of unusual bacteria as potential causative organisms of osteomyelitis is imperative for appropriate treatment.

Thromboembolic complications after major thoracolumbar spine surgery

STUDY DESIGN

Adult spinal surgery patients were studied prospectively to determine the incidence of subclinical deep venous thrombosis. An overlapping group of patients was reviewed retrospectively for symptomatic thromboembolism.

OBJECTIVES

To determine the incidence of symptomatic and asymptomatic thromboembolism in spinal surgery patients.

SUMMARY OF BACKGROUND DATA

Although thromboembolic complications are known to occur after spinal operations, there are limited published data on the incidence of pulmonary embolus or deep venous thrombosis after major spinal surgery.

METHODS

One hundred sixteen adult spinal surgery patients were examined with duplex ultrasound to determine the incidence of deep venous thrombosis. Seventy-three of these patients also underwent lung perfusion scans to look for subclinical pulmonary embolism. A retrospective review was conducted of symptomatic thromboembolic complications occurring in a 2-year period at the authors' center. Three hundred and eighteen major spinal reconstructive procedures were performed during the period reviewed, which included the period of the prospective study and therefore the patients of the prospective group. Thigh-length compression stockings and pneumatic compression leggings were used for prophylaxis in all patients.

RESULTS

One patient had an asymptomatic iliac vein thrombosis, and seven patients had symptomatic pulmonary embolism (2.2%). Six of the symptomatic pulmonary emboli occurred after combined anterior/posterior spinal fusions (6%), whereas only one occurred after posterior decompression and fusion (0.5%).

CONCLUSIONS

Duplex ultrasound appeared insensitive for diagnosing clots before embolization in this patient group. Simple mechanical prophylaxis for thromboembolism, which may be adequate for patients undergoing posterior procedures, may not be as protective for patients undergoing combined anterior/posterior spine surgery.

Management of spondylolysis and spondylolisthesis in the pediatric and adolescent population

Spondylolysis and low-grade spondylolisthesis are diagnoses that, for most patients, have a benign prognosis and can be managed nonoperatively. For most symptomatic patients for whom this management fails, fusion in situ yields satisfactory and lasting results and remains the gold standard against which other surgical treatment must be compared. Patients with high-grade slips and slip angles may benefit from instrumented fusion in situ or combined anterior/posterior procedures, or may be considered for reduction and fusion. Reduction maneuvers are technically demanding and carry significant risk of neurologic injury. Surgical experience and in-depth understanding of the indications, the complications, and, especially, the limitations of each technique are required.

Patient outcomes after decompression and instrumented posterior spinal fusion for degenerative spondylolisthesis

STUDY DESIGN

A retrospective study of patient outcomes after decompression and fusion for degenerative spondylolisthesis, using the SF-36 survey and a functional questionnaire.

SUMMARY OF BACKGROUND DATA

In recent studies, patient outcomes have been examined more specifically; however, detailed functional outcomes are not available nor have widely used outcomes instruments been administered.

METHODS

Thirty patients aged more than 40 years (average, 60.1 years) who had degenerative spondylolisthesis were evaluated after decompression and instrumented posterior fusion. Charts and radiographs were also reviewed. Questionnaires were administered by telephone, and consisted of the Medical Outcomes Study short form (SF-36) and 27 questions designed to evaluate function, quality of life, medication usage, and satisfaction with surgical results.

RESULTS

Ninety-three percent of patient's were satisfied with their outcomes. Patients improved significantly in their ability to perform heavy and light activities, participate in social activities, sit, and sleep (P < 0.001) and also improved in pain, depression, and medication usage (P < 0.0001). SF-36 data showed significantly better overall assessment of health in all categories than that in a published cohort of patients with low back pain. The current study group also showed no difference in seven of eight categories when compared with the general population. Fusion rate was 93% at an average of 128 days. Three patients required reoperation: two for pseudarthrosis and one for a deep infection. A poorer outcome, scored by the SF-36, was associated with greater preoperative stenosis (P < 0.05) or occurrence of a complication (P < 0.05).

CONCLUSIONS

Patients treated with decompression and fusion for degenerative spondylolisthesis had improved functional outcomes, when measured by a disease-specific questionnaire and by widely used instruments.

Nutritional depletion in staged spinal reconstructive surgery. The effect of total parenteral nutrition

STUDY DESIGN

A prospective randomized study evaluating nutritional depletion in spine surgery patients.

OBJECTIVE

To determine whether use of total parenteral nutrition (TPN) in patients undergoing staged spinal reconstructive procedures could affect their nutritional parameters or decrease their complication rates.

SUMMARY OF BACKGROUND DATA

Several studies have shown that nutritional depletion occurs after major spinal surgery and that patients undergoing staged spinal surgery may be at particular risk of nutritional loss and its complications.

METHODS

Forty adult patients undergoing staged spinal reconstructive surgery were randomized as to whether they received TPN postoperatively. Nutritional parameters, including skin fold measurement and albumin, pre-albumin, transferrin, and total lymphocyte counts, were obtained pre-operatively and at regular intervals.

RESULTS

Five patients did not complete the study, leaving 35 patients for analysis. There was a significant decrease in incidence of albumin and pre-albumin depletion for the patients who did not receive TPN compared with those who did receive TPN (P < 0.025, P < 0.006, respectively). Patients with depleted albumin or pre-albumin counts were more likely to develop other postoperative infectious complications such as pneumonia or urinary tract infections (P < 0.035). There were no statistically significant differences in wound complications in this small patient study. There were no complications secondary to use of the TPN.

CONCLUSIONS

For complex patients requiring staged anterior/posterior surgery, TPN appears to significantly lessen the decrease in nutritional parameters. Because depletion of nutritional parameters appears to correlate with an increased likelihood of perioperative infectious complications, use of TPN may result in a decrease of such complications in these patients.

Effect of the pedicle and posterior arch on vertebral body strength predictions in finite element modeling

STUDY DESIGN

A finite element study to predict the contribution of the pedicles and the posterior arch to vertebral body strength.

OBJECTIVE

To determine the effect of the pedicle and posterior arch on strain distributions occurring within the vertebral body under axial compressive loading.

SUMMARY OF BACKGROUND DATA

Posterior vertebral body fracture can arise from high-impact or normal loading in bones compromised by osteoporosis or neoplasm and can result in spinal canal encroachment. Anatomically, the pedicles and posterior arch have a potential role as a structural buttress to the posterior vertebral body wall. However, most finite element models used to investigate vertebral body strength have neglected these structures.

METHODS

Three 3-dimensional finite element models were developed of L1, incorporating anatomic curvature, with varying degrees of posterior element inclusion (no pedicle, pedicle, and pedicle and posterior arch). Three cases were analyzed with each model: 25% dehydrated disc, normal healthy disc, and uniform pressure loading. Outcome variables were the maximum von Mises strains and the displacement of the posterior wall into the spinal canal.

RESULTS

Inclusion of the posterior arch resulted in substantial decreases in maximum strain and posterior wall displacement under all loading configurations using transversely isotropic trabecular bone properties. No changes in maximum strains or displacements were recorded in the pedicle model, compared with that observed in the no-pedicle baseline case.

CONCLUSIONS

The pedicle functions as a structural buttress, providing support to the posterior wall of the vertebral body when constrained through the posterior arch. To yield more accurate vertebral body strength predictions from finite element modeling, the posterior arch should be included.

Internal fixation in the osteoporotic spine

The presence of osteoporosis in patients who are candidates for spinal surgery can affect preoperative planning. These patients may not need instrumentation for a successful surgical result, but if use of instrumentation is indicated because of instability or deformity, certain principles should be observed. These include using multiple sites of fixation, accepting lesser degrees of deformity correction, and avoiding ending the instrumentation within kyphotic segments. Advances in perioperative medical management, as well as improved instrumentation systems, may also contribute to improving patient outcomes.

Revision of failed lumbar fusions. A comparison of anterior autograft and allograft

STUDY DESIGN

The radiographic and clinical results of two different anterior structural grafts were compared in 38 patients who had combined anterior-posterior revision surgery for failed lumbar fusion.

OBJECTIVES

Failed lumbar fusion surgery, such as pseudarthrosis or flatback deformity, may result in disabling pain. The optimum revision technique has yet to be defined. The authors of the current study sought to determine which of two different types of anterior graft yields the best results.

SUMMARY OF BACKGROUND DATA

Posterior procedures for revision of a failed lumbar fusion have not yielded reliably successful results. A combined anterior-posterior approach may be effective in restoring sagittal balance and enhancing fusion rates. Recent studies have shown femoral ring allografts to be effective in lumbar fusion revision, but no studies have compared these with other types of structural grafts.

METHODS

Thirty-eight patients with pseudarthrosis were treated with combined anterior-posterior lumbar spine fusion using either femoral ring allografts (26 patients) or tricortical iliac autografts (12 patients). Radiographic follow-up examination and retrospective patient self-assessment questionnaires were used to evaluate outcomes. Results were assessed by independent reviewers after a mean follow-up period of 35 months.

RESULTS

Radiographic follow-up examination revealed acceptably low pseudarthrosis rates for structural autografts (0%) and allografts (6%). The questionnaires revealed significant improvement in pain for both groups. Allograft patients showed greater improvement in function, less pain medication usage, and higher overall success rates (83%) than autograft patients (64%).

CONCLUSIONS

Femoral ring allografts are as effective, clinically and radiographically, as tricortical iliac autografts when used as an anterior structural element in revision lumbar spine fusion in patients who have undergone multiple surgical procedures for pseudarthrosis or flatback deformity. The slightly greater improvement for the allograft group needs to be confirmed in a larger study.

Carbonated apatite cement augmentation of pedicle screw fixation in the lumbar spine

STUDY DESIGN

Biomechanical testing with human cadaveric lumbar vertebral bodies was used to determine the utility of an injectable carbonated apatite cancellous bone cement for improving the structural performance of pedicle screws subjected to axial pull-out or transverse cyclic loading.

OBJECTIVES

To ascertain whether augmentation with a carbonated apatite cement can enhance pedicle screw fixation in the lumbar spine.

SUMMARY OF BACKGROUND DATA

The beneficial effects of polymethylmethacrylate augmentation on pedicle screw pull-out strength have been demonstrated. Cancellous bone cement, however, may provide an attractive alternative in this application, as it is remodelable, biocompatible, and nonexothermic.

METHODS

Forty-three cadaveric lumbar vertebral bodies were instrumented with pedicle screws. In 20 of these specimens, axial pull-out strength was compared between the control screws and those augmented with cancellous bone cement. In the remaining 23 specimens, the screws were loaded in the superior-inferior direction with a peak displacement of +/- 1 mm at a frequency of 3 Hz for 5000 cycles. Three parameters were calculated from the force-versus-time data: 1) the energy dissipated, 2) the peak force at the start of the test, and 3) the peak force at the end of 5000 cycles.

RESULTS

The pull-out strength of the augmented pedicles averaged 68% greater than that of the control side. In response to cyclic loading, all measures of bio-mechanical performance improved 30-63%.

CONCLUSIONS

The data suggest that augmentation with this carbonated apatite cancellous bone cement can enhance immediate screw fixation.

Postural imbalance and vibratory sensitivity in patients with idiopathic scoliosis: implications for treatment

Sporadic research reports of decreased proprioception and balance problems have been reported in subjects with idiopathic scoliosis, yet these sensory motor deficits have not been addressed in conservative clinical management programs. The purpose of this study was to compare both balance reactions and vibratory sensitivity (as an estimate of proprioception) in patients with idiopathic scoliosis (N = 24) and age-matched controls (N = 24). Balance was measured by the ability to pass a series of simple static and complex sensory-challenged balance tasks. Vibratory thresholds were measured with the Bio-Thesiometer at the cervical spine, wrist, and foot. Compared with age-matched controls, regardless of curve severity or spinal fusion, the subjects with idiopathic scoliosis had similar simple static balance responses when the somatosensory system was stable (with or without vision or head turning), but they were significantly more likely to fail the complex, sensory-challenged balance tasks when the somatosensory system was challenged by an unstable position of the feet, particularly when the eyes were closed. The vibratory thresholds were similar in subjects with scoliosis and their age-matched controls, but individuals with moderate to severe scoliosis (> 25 degrees) had significantly higher vibratory thresholds than those with mild curves. These findings suggest there may be problems with postural righting in patients with idiopathic scoliosis, particularly when the balance task challenges the vestibular pathways. Although vibration sensitivity did not distinguish normal healthy individuals from individuals with idiopathic scoliosis, those with more severe scoliotic curves appear to have a high threshold to vibration. These balance and vibratory differences could either be interpreted as etiologic risk factors or as consequences of spinal asymmetry. In either case, given that curves can continue to progress even into the adult years, improving the ability to right the body with gravity could help maintain the balance of the spine despite structural asymmetry.

Patient outcomes after spinal reconstructive surgery in patients > or = 40 years of age

This study provides outcome data on the quality of life in 84 patients 40 years of age or older who had spinal reconstructive surgery. A 30-min questionnaire covering the patients' pre- and postoperative functional status, expectations for surgery, medication use, quality of life, and overall satisfaction was administered via telephone by a trained interviewer. Clinical data were obtained from chart and radiographic review. The majority of the patients had back or leg pain as their indication for surgery. Diagnoses included kyphosis, scoliosis, spinal stenosis, spondylolisthesis, and failed surgery. Overall satisfaction with functional status and surgical outcome was 81%, and there was significant improvement in most functional measures. This study suggests that improved qualify of life for the majority of appropriately selected spinal reconstruction patients is achievable in this mature population.

Reduction of high-grade spondylolisthesis using Edwards instrumentation

STUDY DESIGN

Sixteen patients with high-grade spondylolisthesis (Grade III or higher) who underwent posterior decompression and reduction using the Edwards Modular Spine System (Spinal System Ltd., Baltimore, MD) were reviewed clinically and radiographically.

OBJECTIVES

This study was undertaken to determine the efficacy of one specific reduction technique to treat patients with high-grade spondylolisthesis where there has been a loss of sagittal balance, intractable pain, and/or neurologic deficit.

SUMMARY OF BACKGROUND DATA

The average age of our patients was 20 years. Preoperative slippage averaged 89%; preoperative slip angle averaged 50 degrees. Indications for surgery were back and leg pain, progression of slippage (in 9 patients), and/or the inability to stand upright with the knees straight.

METHODS

Pre- and postoperative radiographic films were reviewed. The percent slip and the slip angle were measured pre- and postoperatively. Clinical data were obtained via chart review, telephone interview, and/or office visit.

RESULTS

The average preoperative slip was 89%; postoperatively, the average slip was 29%. Slip angle averaged 50 degrees preoperatively and improved to a postoperative average of 24 degrees. Three patients had neurologic impairment postoperatively; one did not resolve. Four patients had hardware failure; all were revised. Ten patients had an excellent result, 5 patients had a good result, and 1 patient had a fair result. The average follow-up was 3.8 years.

CONCLUSION

This procedure is technically demanding and is subject to the known risks of surgical treatment for high-grade spondylolisthesis. For select patients, it may be effective for reducing severe deformity and can be expected to afford good to excellent results. Improved sacral fixation may reduce the rate of hardware-related complications.

Pediatric spinal infections

A high index of suspicion for spinal infection and an appropriate and prompt diagnosis are essential for the treatment of pediatric spinal infections. A 3-week course of antibiotics and supportive therapy is effective in the majority of cases of discitis, the most common pediatric spinal infection. Patients who are not toxic may be treated with bracing, or with casting alone in many cases. Neurologic deficit or a failure to respond to early treatment requires more aggressive measures, including biopsy or surgical debridement. It is essential to diagnose rare but serious conditions such as epidural abscess, tuberculosis, or opportunistic infections in patients at risk. The authors stress that clinical evaluation and appropriate diagnosis are critical for prevention of permanent neurologic damage or late bony deformity.

Instrumentation of the cervicothoracic junction after destabilization

STUDY DESIGN

The biomechanics of three different instrumentation constructs applied at the destabilized cervicothoracic junction were evaluated.

OBJECTIVES

To find an efficient way in restoring stability of the cervicothoracic junction in cases with and without laminectomy.

SUMMARY OF BACKGROUND DATA

Different instrumentation techniques have been evaluated biomechanically and used clinically for managing instabilities between the fourth and sixth cervical vertebrae. These constructs have not been evaluated at the cervicothoracic junction.

METHODS

Six human spines were tested nondestructively in axial torsion, flexion, and extension with the C6-T2 motion segments left unconstrained. The three-dimensional displacements and rotations between C7 and T1 vertebrae were measured using a sonic digitizer. After intact testing, a distractive-flexion Stage 3 cervical spinal injury was simulated surgically between C7 and T1. The specimens underwent sequential instrumentation and mechanical testing with three constructs: posterior Synthes lateral mass plate, posterior pediatric Cotrel-Dubousset rod system with lamina hooks and a crosslink, and anterior Synthes cervical locking plate.

RESULTS

Posterior stabilization techniques had statistically more stiffness than anterior plates. The Cotrel-Dubousset system offered the largest stiffness ratio (instrumented/intact) in flexion, extension, and rotation. There was no statistical difference between posterior plates and Cotrel-Dubousset instrumentation. The stiffness of the anterior plate did not differ significantly from the intact spine.

CONCLUSION

Our data show that instability of the cervicothoracic junction can be efficiently restored by either anterior plates, posterior plates, or posterior hook-rod constructs (Cotrel-Dubousset). Posterior constructs showed increased stiffness over anterior plates.

The antiproliferative activity of c-myb and c-myc antisense oligonucleotides in smooth muscle cells is caused by a nonantisense mechanism

Smooth muscle cell (SMC) proliferation is thought to play a major role in vascular restenosis after angioplasty and is a serious complication of the procedure. Developing antisense (AS) oligonucleotides as therapeutics is attractive because of the potentially high specificity of binding to their targets, and several investigators have reported inhibition of SMC proliferation in vitro and in vivo by using AS strategies. We report here the results of our experiments on vascular SMCs using AS oligonucleotides directed toward c-myb and c-myc. We found that significant inhibition of SMC proliferation occurred with these specific AS sequences but that this inhibition was clearly not via a hybridization-dependent AS mechanism. Rather, inhibition was due to the presence of four contiguous guanosine residues in the oligonucleotide sequence. This was demonstrated in vitro in primary cultures of SMCs and in arteries ex vivo. The ex vivo model developed here provides a rapid and effective system in which to screen potential oligonucleotide drugs for restenosis. We have further explored the sequence requirements of this non-AS effect and determined that phosphorothioate oligonucleotides containing at least two sets of three or four consecutive guanosine residues inhibit SMC proliferation in vitro and ex vivo. These results suggest that previous AS data obtained using these and similar, contiguous guanosine-containing AS sequences be reevaluated and that there may be an additional class of nucleic acid compounds that have potential as antirestenosis therapeutics.