Initial stability of tibial components in primary knee arthroplasty. A cadaver study comparing cemented and cementless fixation techniques

The purpose of this roentgen stereophotogrammetric analysis (RSA) study was to evaluate the initial stability of cemented and cementless tibial components in vitro. Twenty tibia specimens were matched into two groups. In the first group, the tibial trays were cemented superficially and in the second group cementless fixation with stem and screws was performed. An axial load of 2000 N for 1000 and 10,000 cycles was applied onto the specimens and RSA was performed. The experimental results after 1000 cycles showed a higher migration with significant differences for the parameters maximum lift off (p = 0.011) and maximum total point motion (p = 0.002) in the cementless group. After 10,000 cycles, the migration in the cementless group increased significantly for maximum lift off (p = 0.043), maximum subsidence (p = 0.045) and maximum total point motion (p = 0.013). The higher migration rates in the cementless group demonstrate a lower initial mechanical stability of cementless tibial components which can cause an early component loosening.     

The demographics of adverse outcomes in cystic fibrosis

Understanding variability in cystic fibrosis (CF) health outcomes requires an understanding of factors that go far beyond Cystic Fibrosis Transmembrane Receptor (CFTR) function caused by different gene mutations. Social and environmental factors that influence health have a significant influence on the trajectory of health in CF and in other chronic diseases. In this article, we review demographic factors associated with poorer health outcomes in CF, known and postulated biological mechanisms of these outcomes, and interventions that healthcare teams can implement that may reduce outcome disparities.     

Association between isometric muscle strength and gait joint kinetics in adolescents and young adults with cerebral palsy

The purpose of this study was to determine the association between isometric muscle strength of the lower limbs and gait joint kinetics in adolescents and young adults with cerebral palsy (CP). Twenty-five participants (11 males) with bilateral spastic CP, aged 14-22 years (mean: 18.9, sd: 2.0 yr) and Gross Motor Function Classification System (GMFCS) level II (n=19) and III (n=6) were tested. Hand held dynamometry was used to measure isometric strength (expressed in Nm/kg) of the hip, knee, and ankle muscles using standardized testing positions and procedures. 3D gait analysis was performed with a VICON system to calculate joint kinetics in the hip, knee and ankle during gait. Ankle peak moments exceeded by far the levels of isometric strength of the plantar flexors, while the knee and hip peak moments were just at or below maximal isometric strength of knee and hip muscles. Isometric muscle strength showed weak to moderate correlations with peak ankle and hip extension moment and power during walking. Despite considerable muscle weakness, joint moment curves were similar to norm values. Results suggest that passive stretch of the muscle-tendon complex of the triceps surae contributes to the ankle moment during walking and that muscle strength assessment may provide additional information to gait kinetics.     

Language Use and Adherence to Multiple Cancer Preventive Health Behaviors Among Hispanics

Hispanics have lower cancer mortality rates than non-Hispanic Whites and Blacks, despite demographic profiles previously associated with higher cancer mortality. Differences in adherence to multiple cancer-preventive behaviors by acculturation may offer one explanation for this “Hispanic paradox,” but the relationship is not well understood. We examined this relationship using the 2000 National Health Interview Survey, which provides cross-sectional data on a nationally representative sample of US Hispanics. Multinomial logistic regression models estimated relationships between language use (a measure of acculturation) and patterns of adherence, by gender, to multiple cancer-preventive health behaviors using adherence scores. Hispanics had greater odds of adherence to multiple behaviors compared to Non-Hispanics (OR = 2.76 [2.27, 3.36]). Hispanics with greater English language use had lower odds of adherence (OR = 0.45 [0.29, 0.69]). Women were more adherent than men (P < 0.01) and their language use was associated with patterns of behavioral adherence more so than among men. Differences by gender and language use were identified in patterns of adherence to behavioral recommendations among the Hispanic population. Greater English language use was negatively associated with tobacco, alcohol, fruit and vegetable recommendation adherence but not with exercise. Study findings support evidence behaviors occur in combination and contributes to understanding of the role of language use in patterns of behavioral adherence.     

21st century community learning centers--improving the academic performance of at-risk students: a Bronx tale

The authors of this article report on an intervention designed to improve the academic component of an extended after-school program. The agency involved in this intervention was a non-profit community action group (CAG) agency whose mission is to improve the socio-economic well-being of the residents of Upper Manhattan, the Bronx, and New York City. The agency has a staff of 200 that serve high school students. The intervention program was designed to (1) improve the working relationship between teachers, families, and students in the after-school program, (2) develop new and innovative ways to improve the academic curricula of the after-school program, and (3) provide continuous education to stakeholders to the after-school program. Improvements in student performance relating to attendance, academic work, discipline and social behaviors were reported. The intervention reported in this article has the potential of supporting learning and developmental outcomes over time.     

Pandemic influenza A/H1N1 vaccine administered sequentially or simultaneously with seasonal influenza vaccine to HIV-infected children and adolescents

In order to evaluate the immunogenicity, safety and tolerability of the 2009 A/H1N1 MF59-adjuvanted influenza vaccine administered sequentially or simultaneously with seasonal virosomal-adjuvanted influenza vaccine to HIV-infected children and adolescents, 36 HIV-infected children and adolescents, and 36 age- and gender-matched healthy controls were randomised 1:1 to receive the pandemic vaccine upon enrolment and the seasonal vaccine one month later, or to receive the pandemic and seasonal vaccines simultaneously upon enrolment. Seroconversion and seroprotection rates against the pandemic influenza A/H1N1 virus were 100% two months after vaccine administration in both groups, regardless of the sequence of administration. Geometric mean titres against pandemic and seasonal antigens were significantly higher when the seasonal and pandemic vaccines were administered simultaneously than when the seasonal vaccine was administered alone. Local and systemic reactions were mild and not increased by simultaneous administration. In conclusion, the 2009 pandemic influenza A/H1N1 MF59-adjuvanted vaccine is as immunogenic, safe and well tolerated in HIV-infected children and adolescents as in healthy controls. Its simultaneous administration with virosomal-adjuvanted seasonal antigens seems to increase immune response to both pandemic and seasonal viruses with the same safety profile as that of the pandemic vaccine alone. However, because this finding cannot be clearly explained by an immunological viewpoint, further studies are needed to clarify the reasons of its occurrence.     

Interventional radiology in the airway in children

Interventional procedures in the airway can be performed in interventional radiology suites or the operating room, by radiologists or other specialists. The most common therapeutic interventions carried out by radiologists are balloon dilatation, stenting, and the treatment of certain airway fistulas. These operations can be very challenging for anesthetists in terms of planning, airway management, the identification and treatment of procedural complications and postoperative care. In particular, a multidisciplinary approach to decision‐making and planning is important to obtain the best results.