Statistical analysis of arthroplasty data: II. Guidelines

It is envisaged that guidelines for statistical analysis and presentation of results will improve the quality and value of research. The Nordic Arthroplasty Register Association (NARA) has therefore developed guidelines for the statistical analysis of arthroplasty register data. The guidelines are divided into two parts, one with an introduction and a discussion of the background to the guidelines (Ranstam et al. 2011a, see pages x-y in this issue), and this one with a more technical statistical discussion on how specific problems can be handled. This second part contains (1) recommendations for the interpretation of methods used to calculate survival, (2) recommendations on howto deal with bilateral observations, and (3) a discussion of problems and pitfalls associated with analysis of factors that influence survival or comparisons between outcomes extracted from different hospitals

Incidence and trends of low back pain hospitalisation during military service – An analysis of 387,070 Finnish young males

<p>Abstract</p> <p>Background</p> <p>There is evidence that low back pain (LBP) during young adulthood and military service predicts LBP later in life. The purpose of this study was to investigate the incidence and trends of LBP hospitalisation among Finnish military conscripts.</p> <p>Methods</p> <p>All male conscripts performing their compulsory military service during 1990–2002 were included in the study population. Altogether 387,070 military conscripts were followed throughout their six-to-twelve-month service period. Data on LBP hospitalisations were obtained from the National Hospital Discharge Register.</p> <p>Results</p> <p>Altogether 7,240 LBP hospitalisations were identified among 5,061 (1.3%) male conscripts during the study period. The event-based incidence of LBP hospitalisation was 27.0 (95% confidence interval (CI): 25.7–28.2). In most cases, the diagnosis was unspecified LBP (<it>n </it>= 5,141, 71%) followed by lumbar disc disorders (<it>n </it>= 2,069, 29%). Hospitalisation incidence due to unspecified LBP was 19.1 per 1,000 person-years (95% CI: 18.3 to 20.4), and 7.8 per 1,000 person-years (95% CI: 6.7 to 8.3) due to lumbar disc disorders. The incidence of unspecified LBP remained unaltered, while hospitalisation due to lumbar disc disorders declined from 1993 onwards.</p> <p>Conclusion</p> <p>Although conscripts accepted into military training pass physician-performed examinations as healthy, young adults, LBP hospitalisation causes significant morbidity during military service.</p

Effects of metal-on-metal wear on the host immune system and infection in hip arthroplasty

Methods We reviewed the available literature on the influence of degradation products of MOM bearings in total hip arthroplasties on infection risk. Results Wear products were found to influence the risk of infection by hampering the immune system, by inhibiting or accelerating bacterial growth, and by a possible antibiotic resistance and heavy metal co-selection mechanism. Interpretation Whether or not the combined effects of MOM wear products make MOM bearings less or more prone to infection requires investigation in the near future

Increased Mortality in Metal-on-Metal versus Non-Metal-on-Metal Primary Total Hip Arthroplasty at 10 Years and Longer Follow-Up: A Systematic Review and Meta-Analysis

Analysis and Stochastic

Physical and sports activity after hip arthroplasty

A artroplastia é utilizada para reconstrução da articulação do quadril, visando minimizar a dor e possibilitar o retorno às atividades de vida diária, esportivas e de lazer. O objetivo deste artigo é analisar na literatura as indicações e contraindicações referentes à prática de atividade física, esportiva e lazer após a artroplastia de quadril. Essa revisão aborda estudos publicados entre os anos de 1980 e 2009, obtidos por buscas em bancos de dados eletrônicos Medline, Scielo, Ovid, Infomaworld, Sciencedirect, Springerlink, Interscience, Sportdiscuss, Bireme, Informglobal, Opas, Ovid, Diseasedex, Eric, que totalizaram 39 artigos. Os artigos analisados apontam para a utilização de atividade física, esportiva e de lazer de baixo impacto. como a caminhada, natação, boliche, ciclismo, dentre outras. Outra indicação constatada na literatura é a utilização da atividade física e esportiva visando à manutenção do condicionamento físico, qualidade óssea e controle do peso corporal. Há ressalvas na literatura sobre a utilização de atividades de alto impacto, esporte com giro como o basquete e futebol ou com grande intensidade como tênis e a corrida, bem como os esportes de luta. As atividades físicas, esportivas e de lazer mais indicadas após uma atroplastia de quadril são as de baixo impacto como a hidroginástica, natação, caminhada, dentre outras. O início dessas atividades deve aguardar a liberação do médico, mas em média iniciam 60 dias após a cirurgia.Hip arthroplasty is used for reconstruction of the hip joint to reduce pain and to make the return to daily life, physical, sports and leisure activities possible. The objective of this article was to analyze in the literature the indications and counter-indications referring to practice of physical, sportive and leisure activities after hip arthroplasty. This revision approaches studies published between 1980 and 2009, obtained in searches in the Medline, Scielo, Ovid, Infomaworld, Sciencedirect, Springerlink, Interscience, Sportdiscuss, Bireme, Informglobal, Opas, Ovid, Diseasedex and Erics electronic databases with a total of 39 articles. The analyzed articles point to the use of physical, leisure and sports of low impact activities such as walking, swimming, bowling, cycling and others. Another indication evidenced in the literature is the use of physical and sportive activity aiming at the maintenance of physical fitness, bone quality and body weight control. The literature shows concerns with the use of activities of high impact or with great intensity like tennis and jogging, as well as fights

Treatments for people who use anabolic androgenic steroids: a scoping review.

BACKGROUND: A growing body of evidence suggests that anabolic androgenic steroids (AAS) are used globally by a diverse population with varying motivations. Evidence has increased greatly in recent years to support understanding of this form of substance use and the associated health harms, but there remains little evidence regarding interventions to support cessation and treat the consequences of use. In this scoping review, we identify and describe what is known about interventions that aim to support and achieve cessation of AAS, and treat and prevent associated health problems. METHODS: A comprehensive search strategy was developed in four bibliographic databases, supported by an iterative citation searching process to identify eligible studies. Studies of any psychological or medical treatment interventions delivered in response to non-prescribed use of AAS or an associated harm in any setting were eligible. RESULTS: In total, 109 eligible studies were identified, which included case reports representing a diverse range of disciplines and sources. Studies predominantly focussed on treatments for harms associated with AAS use, with scant evidence on interventions to support cessation of AAS use or responding to dependence. The types of conditions requiring treatment included psychiatric, neuroendocrine, hepatic, kidney, cardiovascular, musculoskeletal and infectious. There was limited evidence of engagement with users or delivery of psychosocial interventions as part of treatment for any condition, and of harm reduction interventions initiated alongside, or following, treatment. Findings were limited throughout by the case report study designs and limited information was provided. CONCLUSION: This scoping review indicates that while a range of case reports describe treatments provided to AAS users, there is scarce evidence on treating dependence, managing withdrawal, or initiating behaviour change in users in any settings. Evidence is urgently required to support the development of effective services for users and of evidence-based guidance and interventions to respond to users in a range of healthcare settings. More consistent reporting in articles of whether engagement or assessment relating to AAS was initiated, and publication within broader health- or drug-related journals, will support development of the evidence base

A mathematical model for the thermal state of a steel ladle

Abstract A dynamic one-dimensional mathematical model was developed for predicting the thermal state of a steelmaking ladle. The model is intended to be used in process control applications, in which fast computational times are desirable alongside model accuracy. The calculation domain was discretized using the finite difference method, and time integration was performed using both the implicit Euler and Crank–Nicolson methods, the performances of which were compared. The model was implemented in Python programming language and validated using data from our own measurements and other studies available in the literature. The results indicate that the model can reproduce the measured temperature evolution of the ladles within 5°C at best. The worst performance was observed during cooling, where the model underestimates the temperature at the innermost measurement point by up to 200°C. With computation times of around 16–23 s for one hour of simulation, the model is computationally sufficiently fast for online applications