Nonoperative Management of Shoulder Instability

Non-operative management following a shoulder dislocation or subluxation remains a challenging and complex task. Accurate diagnosis of the condition, and shared decision-making regarding operative and non-operative management, as well as timing of return to play is required. This clinical concept paper introduces a shoulder instability framework that addresses these fundamental clinical dilemmas. Valid clinical prognostic tools which can predict recurrent shoulder instability are reviewed. The process of shared decision-making within the realm of shoulder instability is also presented. Finally, a framework for progressive rehabilitation that addresses deficits in motor control, strength, and endurance in scapula and shoulder musculature is presented to guide patients from an initial instability event, through to return to play

Systems And Method To Deliver Addressable Advertisements

System and method are disclosed for customizable ad delivery to targeted clients with efficient bandwidth usage. The system includes an ad server, asynchronous ad delivery server and an ad client. The ad client in a set top box (STB) device periodically requests for a set of possible ads from the asynchronous ad delivery server. The asynchronous ad delivery server is directly interfaced to the ad server and communicates with the ad server to determine a set of possible ads. The ad delivery server responds to the client request for possible ads by generating the customized ads. The asynchronous ad delivery server delivers customized ads to STB client storage. The STB client shows the customized ads from storage. The ad content cache is limited only by the size of the storage on the STB, which may be used effectively to minimize bandwidth demand by scheduling ad requests during lean usage period

Does home equipment contribute to socioeconomic gradients in Australian children’s physical activity, sedentary time and screen time?

Abstract Background Activity behaviours (physical activity, sedentary time and screen time) have been linked to health outcomes in childhood. Furthermore, socioeconomic disparities have been observed in both children’s activity behaviours and health outcomes. Children’s physical home environments may play a role in these relationships. This study aimed to examine the associations and interactions between children’s physical home environment, socioeconomic status and moderate-to-vigorous physical activity, sedentary time and screen time. Methods Australian children (n = 528) aged 9–11 years from randomly selected schools participated in the cross-sectional International Study of Childhood Obesity, Lifestyle and the Environment. Children’s physical home environment (access to equipment), socioeconomic status (household income and parental education) and demographic variables (gender and family structure) were determined by parental questionnaire. Moderate-to-vigorous physical activity and sedentary time were measured objectively by 7-day 24-h accelerometry. Screen time was obtained from child survey. The associations between the physical home environment, socioeconomic status and moderate-to-vigorous physical activity, sedentary time and screen time were examined for 427 children, using analysis of covariance, and linear and logistic regression, with adjustment for gender and family structure. Results The presence of TVs (p < 0.01) and video game consoles (p < 0.01) in children’s bedrooms, and child possession of handheld video games (p = 0.04), cell phones (p < 0.01) and music devices (p = 0.04) was significantly and positively associated with screen time. Ownership of these devices (with the exception of music devices) was inversely related to socioeconomic status (parental education). Children’s moderate-to-vigorous intensity physical activity (p = 0.04) and possession of active play equipment (p = 0.04) were both positively associated with socioeconomic status (household income), but were not related to each other (with the exception of bicycle ownership). Conclusions Children with less electronic devices, particularly in their bedrooms, participated in less screen time, regardless of socioeconomic status. Socioeconomic disparities were identified in children’s moderate-to-vigorous physical activity, however socioeconomic status was inconsistently related to possession of active play equipment. Home active play equipment was therefore not a clear contributor to the socioeconomic gradients in Australian children’s moderate-to-vigorous physical activity

It's not just the television: survey analysis of sedentary behaviour in New Zealand young people

<p>Abstract</p> <p>Background</p> <p>Sedentary behaviour has been linked with adverse health outcomes in young people; however, the nature and context of being sedentary is poorly understood. Accurate quantification and description of sedentary behaviour using population-level data is required. The aim of this research was to describe sedentary behaviour among New Zealand (NZ) youth and examine whether sedentary behaviour differs by Body Mass Index (BMI) status in this population.</p> <p>Methods</p> <p>A national representative cross-sectional survey of young people aged 5-24 years (n = 2,503) was conducted in 2008-2009. Data from this survey, which included subjectively (recall diary; n = 1,309) and objectively (accelerometry; n = 960) measured sedentary behaviour for participants aged 10-18 years were analysed using survey weighted methods.</p> <p>Results</p> <p>Participants self-reported spending on average 521 minutes per day (standard error [SE] 5.29) in total sedentary behaviour, 181 minutes per day (SE 3.91) in screen-based sedentary activities (e.g., television and video games), and 340 minutes per day (SE 5.22) in other non-screen sedentary behaviours (e.g., school, passive transport and self-care). Accelerometer-measured total sedentary behaviour was on average 420 minutes per day (SE 4.26), or 53% (SE 0.42%) of monitored time. There were no statistically significant differences in time spent in sedentary behaviour among overweight, obese and healthy/underweight young people.</p> <p>Conclusions</p> <p>Both subjective and objective methods indicate that NZ youth spend much of their waking time being sedentary. No relationships were found between sedentary behaviour and BMI status. These findings extend previous research by describing engagement in specific sedentary activities, as well as quantifying the behaviour using an objective method. Differences in what aspects of sedentary behaviour the two methods are capturing are discussed. This research highlights the potential for future interventions to target specific sedentary behaviours or demographic groups.</p

Characterizing High-Energy-Density Propellants for Space Propulsion Apllications

57th International Astronautical Congress October 2006, Valencia, Spain.A technique for determining the thermophysical properties of high-energy-density matter (HEDM) propellants is presented. HEDM compounds are of interest in the liquid rocket engine industry due to their high density and high energy content relative to existing industry standard propellants (liquid hydrogen, kerosene, and hydrazine). In order to model rocket engine performance, cost, and weight in a conceptual design environment, several thermodynamic and physical properties are needed. These properties include enthalpy, entropy, density, viscosity, and thermal conductivity. These properties need to be known over a wide range of temperature and pressure. A technique using a combination of quantum mechanics and molecular dynamics is used to determine these properties for quadricyclane, a HEDM compound of interest. Good agreement is shown with experimentally measured thermophysical properties. A vehicle case study is provided to quantify the system level benefits of using quadricyclane instead of hydrazine for the lunar lander ascent stage of the Exploration Systems Architecture Study. The results show that the use of HEDM propellants can significantly reduce the lunar lander mass and indicate that HEDM propellants are an attractive technology to pursue for future lunar missions

Cross-sectional and longitudinal associations between active commuting and patterns of movement behaviour during discretionary time: A compositional data analysis.

BACKGROUND: Active living approaches seek to promote physical activity and reduce sedentary time across different domains, including through active travel. However, there is little information on how movement behaviours in different domains relate to each other. We used compositional data analysis to explore associations between active commuting and patterns of movement behaviour during discretionary time. METHODS AND FINDINGS: We analysed cross-sectional and longitudinal data from the UK Biobank study. At baseline (2006-2010) and follow up (2009-2013) participants reported their mode of travel to work, dichotomised as active (walking, cycling or public transport) or inactive (car). Participants also reported activities performed during discretionary time, categorised as (i) screen time; (ii) walking for pleasure; and (iii) sport and do-it-yourself (DIY) activities, summed to produce a total. We applied compositional data analysis to test for associations between active commuting and the composition and total amount of discretionary time, using linear regression models adjusted for covariates. Adverse events were not investigated in this observational analysis. The survey response rate was 5.5%. In the cross-sectional analysis (n = 182,406; mean age = 52 years; 51% female), active commuters engaged in relatively less screen time than those who used inactive modes (coefficient -0.12, 95% confidence interval [CI] -0.13 to -0.11), equating to approximately 60 minutes less screen time per week. Similarly, in the longitudinal analysis (n = 4,323; mean age = 51 years; 49% female) there were relative reductions in screen time in those who used active modes at both time points compared with those who used inactive modes at both time points (coefficient -0.15, 95% confidence interval [CI] -0.24 to -0.06), equating to a difference between these commute groups of approximately 30 minutes per week at follow up. However, as exposures and outcomes were measured concurrently, reverse causation is possible. CONCLUSIONS: Active commuting was associated with a more favourable pattern of movement behaviour during discretionary time. Active commuters accumulated 30-60 minutes less screen time per week than those using inactive modes. Though modest, this could have a cumulative effect on health over time.LF was funded by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence. Funding from the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research, and the Wellcome Trust, under the auspices of the UK Clinical Research Collaboration, is gratefully acknowledged (087636/Z/08/Z, ES/G007462/1, MR/K023187/1). DO (MC_UU_12015/6) and KW (MC_UU_12015/3) were supported by the Medical Research Council

Validity and bias on the online active Australia survey: Activity level and participant factors associated with self-report bias

Background This study examined the criterion validity of the online Active Australia Survey, using accelerometry as the criterion, and whether self-report bias was related to level of activity, age, sex, education, body mass index and health-related quality of life. Methods The online Active Australia Survey was validated against the GENEActiv accelerometer as a direct measure of activity. Participants (n = 344) wore an accelerometer for 7 days, completed the Active Australia Survey, and reported their health and demographic characteristics. A Spearman’s rank coefficient examined the association between minutes of moderate-to-vigorous physical activity recorded on the Active Australia Survey and GENEActiv accelerometer. A Bland-Altman plot illustrated self-report bias (the difference between methods). Linear mixed effects modelling was used to examine whether participant factors predicted self-report bias. Results The association between moderate-to-vigorous physical activity reported on the online Active Australia Survey and accelerometer was significant (rs = .27, p \u3c .001). Participants reported 4 fewer minutes per day on the Active Australia Survey than was recorded by accelerometry (95% limits of agreement −104 – 96 min) but the difference was not significant (t(343) = −1.40, p = .16). Self-report bias was negatively associated with minutes of accelerometer-recorded moderate-to-vigorous physical activity and positively associated with mental health-related quality of life. Conclusions The online Active Australia Survey showed limited criterion validity against accelerometry. Self-report bias was related to activity level and mental health-related quality of life. Caution is recommended when interpreting studies using the online Active Australia Survey

Line Hops and Side Hold Rotation Tests Load Both Anterior and Posterior Shoulder: A Biomechanical Study

Background: Clinical tests should replicate the stressful positions encountered during sport participation. Evaluating the kinetic and electromyographical demands of clinical tests enables clinicians to choose appropriate tests for specific sports. Purpose: To describe the shoulder forces and muscle activation levels during closed chain functional tests of Line Hops (LH) and Side Hold Rotation (SHR). Study Design: Descriptive biomechanical study. Methods: Ten asymptomatic participants were examined in a university laboratory. Two functional tests were evaluated using three-dimensional video analysis and electromyography to measure shoulder forces, moments, and muscular activity levels. Results: SHR produced a peak average posterior translation force of 4.84 N/kg (CI95 4.32-5.36N/kg) and a peak average anterior translational force of 1.57 N/kg (CI95 1.10-2.01N/kg). High levels of serratus anterior (98% maximum voluntary isometric contraction (MVIC) and infraspinatus (52 %MVIC) were recorded during SHR. LH produced a posterior translational force of 4.25 N/kg (CI95 3.44–5.06N/kg). High levels of serratus anterior (105 %MVIC) and infraspinatus (87 %MVIC) were recorded during the push off phase of this activity. Conclusions: LH and SHR placed large posterior translational forces that approached half of a person\u27s bodyweight on shoulder structures. SHR produced an anterior translation force at extremes of horizontal abduction placing approximately 18% of bodyweight on shoulder structures. The LH test required the serratus anterior to provide power to push the upper torso of the ground while both the serratus and the infraspinatus provides scapular and humeral stability, respectively. Level of Evidence: 4: Case series

A great sporting nation? Sport participation in New Zealand youth

Sport is a key avenue to promote regular physical activity and health inyoung people. The study aim was to describe sport participation in NewZealand young people. A national cross-sectional survey of young peopleaged 5&ndash;24 years (n=2,503) was conducted. Use of time, demographicand anthropometric data were analysed for participants aged 10&ndash;18years (n=1,308) to identify patterns of sport participation. Overall, 894(68%) participants reported engaging in sport. Average daily participationwas 48 minutes of sport and 153 minutes of moderate-vigorous physicalactivity; sport participation therefore accounted for 31% of moderatevigorousphysical activity by time. Sport participation was higher inmales than females, in younger (10&ndash;14 years) than older (15&ndash;18 years)participants, and in Pacific young people than in other ethnic groups.Pacific youth reported the highest participation in team-based sports butthe lowest participation in individual-based sports. There were gender,age and ethnic differences in the most popular sports. Overall, sportparticipation contributed considerably to daily physical activity. Femaleswere particularly &lsquo;at-risk&rsquo; for lower sport participation, and may benefit from targeted intervention. The popularity of sports differed among demographic groups, suggesting it is important to ensure a range of sports are accessible to young people

Electronic media use and academic performance in late childhood: A longitudinal study

Introduction The effects of electronic media use on health has received much attention but less is known about links with academic performance. This study prospectively examines the effect of media use on academic performance in late childhood. Materials and methods 1239 8- to 9-year-olds and their parents were recruited to take part in a prospective, longitudinal study. Academic performance was measured on a national achievement test at baseline and 10–11 years of age. Parents reported on their child’s duration of electronic media use. Results After control for baseline reading, watching more than two hours of television per day at 8–9 years of age predicted a 12-point lower performance in reading at 10–11 years, equivalent to the loss of a third of a year in learning. Using a computer for more than one hour a day predicted a similar 12-point lower numeracy performance. Regarding cross-sectional associations (presumed to capture short-term effects) of media use on numeracy, after controlling for prior media exposure, watching more than two hours of television per day at 10–11 years was concurrently associated with a 12-point lower numeracy score and using a computer for more than one hour per day with a 13-point lower numeracy performance. There was little evidence for concurrent effects on reading. There was no evidence of short- or long-term associations between videogame use and academic performance. Discussion Cumulative television use is associated with poor reading and cumulative computer use with poorer numeracy. Beyond any links between heavy media use and health risks such as obesity, physical activity and mental health, these findings raise a possibility of additional risks of both television and computer use for learning in mid-childhood. These findings carry implications for parents, teachers and clinicians to consider the type and timing of media exposure in developing media plans for children.Peer reviewe