Low-kinetic energy impact response of auxetic and conventional open-cell polyurethane foams

This paper reports quasi-static and low-kinetic energy impact testing of auxetic and conventional open-cell polyurethane foams. The auxetic foams were fabricated using the established thermo-mechanical process originally developed by Lakes. Converted foams were subject to compression along each dimension to 85% and 70% of the unconverted dimension during the conversion process, corresponding to linear compression ratios of 0.85 and 0.7, respectively. The 0.7 linear compression ratio foams were confirmed to have a re-entrant foam cell structure and to be auxetic. Impact tests were performed for kinetic energies up to 4 J using an instrumented drop rig and high speed video. A flat dropper was employed on isolated foams, and a hemisperical shaped dropper on foams covered with a rigid polypropylene outer shell layer. The flat dropper tests provide data on the rate-dependency of the Poisson’s ratio in these foam test specimens. The foam Poisson’s ratios were found to be unaffected by the strain rate for the impact energies considered here. Acceleration-time data are reported along with deformation images from the video footage. The auxetic samples displayed a 6 times reduction in peak acceleration, showing potential in impact protector devices such as shin or thigh protectors in sports equipment applications. Keywords : auxetic, foam, impact, negative Poisson’s rati

Proteomic differences between native and tissue-engineered tendon and ligament

Tendons and ligaments (T/Ls) play key roles in the musculoskeletal system, but they are susceptible to traumatic or age‐related rupture, leading to severe morbidity as well as increased susceptibility to degenerative joint diseases such as osteoarthritis. Tissue engineering represents an attractive therapeutic approach to treating T/L injury but it is hampered by our poor understanding of the defining characteristics of the two tissues. The present study aimed to determine differences in the proteomic profile between native T/Ls and tissue engineered (TE) T/L constructs. The canine long digital extensor tendon and anterior cruciate ligament were analyzed along with 3D TE fibrin‐based constructs created from their cells. Native tendon and ligament differed in their content of key structural proteins, with the ligament being more abundant in fibrocartilaginous proteins. 3D T/L TE constructs contained less extracellular matrix (ECM) proteins and had a greater proportion of cellular‐associated proteins than native tissue, corresponding to their low collagen and high DNA content. Constructs were able to recapitulate native T/L tissue characteristics particularly with regard to ECM proteins. However, 3D T/L TE constructs had similar ECM and cellular protein compositions indicating that cell source may not be an important factor for T/L tissue engineering

Why health visiting? Examining the potential public health benefits from health visiting practice within a universal service: A narrative review of the literature

INTRODUCTION: There is increasing international interest in universal, health promoting services for pregnancy and the first three years of life and the concept of proportionate universalism. Drawing on a narrative review of literature, this paper explores mechanisms by which such services might contribute to health improvement and reducing health inequalities. OBJECTIVES: Through a narrative review of empirical literature, to identify: DESIGN: The paper draws upon a scoping study and narrative review. REVIEW METHODS: We used three complementary approaches to search the widely dispersed literature: Our key inclusion criterion was information about health visiting practice. We included empirical papers from United Kingdom (UK) from 2004 to February 2012 and older seminal papers identified in search (3), identifying a total of 348 papers for inclusion. A thematic content analysis compared the older (up to 2003) with more recent research (2004 onwards). RESULTS: The analysis revealed health visiting practice as potentially characterized by a particular 'orientation to practice.' This embodied the values, skills and attitudes needed to deliver universal health visiting services through salutogenesis (health creation), person-centredness (human valuing) and viewing the person in situation (human ecology). Research about health visiting actions focuses on home visiting, needs assessment and parent-health visitor relationships. The detailed description of health visitors' skills, attitudes, values, and their application in practice, provides an explanation of how universal provision can potentially help to promote health and shift the social gradient of health inequalities. CONCLUSIONS: Identification of needs across an undifferentiated, universal caseload, combined with an outreach style that enhances uptake of needed services and appropriate health or parenting information, creates opportunities for parents who may otherwise have remained unaware of, or unwilling to engage with such provision. There is a lack of evaluative research about health visiting practice, service organization or universal health visiting as potential mechanisms for promoting health and reducing health inequalities. This paper offers a potential foundation for such research in future

Outcome and patients' satisfaction after functional treatment of acute lateral ankle injuries at emergency departments versus family doctor offices

<p>Abstract</p> <p>Background</p> <p>In some Western countries, more and more patients seek initial treatment even for minor injuries at emergency units of hospitals. The initial evaluation and treatment as well as aftercare of these patients require large amounts of personnel and logistical resources, which are limited and costly, especially if compared to treatment by a general practitioner. In this study, we investigated whether outsourcing from our level 1 trauma center to a general practitioner has an influence on patient satisfaction and compliance.</p> <p>Methods</p> <p>This prospective, randomized study, included n = 100 patients who suffered from a lateral ankle ligament injury grade I-II (16, 17). After radiological exclusion of osseous lesions, the patients received early functional treatment and were shown physical therapy exercises to be done at home, without immobilization or the use of stabilizing ortheses. The patients were randomly assigned into two groups of 50 patients each: Group A (ER): Follow-up and final examination in the hospital's emergency unit. Group B (GP): Follow-up by general practitioner, final examination at hospital's emergency unit. The patients were surveyed regarding their satisfaction with the treatment and outcome of the treatment.</p> <p>Results</p> <p>Female and male patients were equally represented in both groups. The age of the patients ranged from 16 – 64 years, with a mean age of 34 years (ER) and 35 years (GP). 98% (n = 98) of all patients were satisfied with their treatment, and 93% (n = 93) were satisfied with the outcome. For these parameters no significant difference between the two groups could be noted (p = 0.7406 and 0.7631 respectively). 39% of all patients acquired stabilizing ortheses like ankle braces (Aircast, Malleoloc etc.) on their own initiative. There was a not significant tendency for more self-acquired ortheses in the group treated by general practicioners (p = 0,2669).</p> <p>Conclusion</p> <p>Patients who first present at the ER with a lateral ankle ligament injury grade I-II can be referred to a general practitioner for follow-up treatment without affecting patient satisfaction regarding treatment and treatment outcome.</p

Risk factors for traumatic and non-traumatic lower limb pain among preadolescents: a population-based study of Finnish schoolchildren

BACKGROUND: The child's lower limb is the most commonly reported musculoskeletal location with pain and also the most commonly injured site in sports. Some potential risk factors have been studied, but the results are inconsistent. We hypothesized that distinction of traumatic from non-traumatic pain would provide a clearer picture of these factors. The aim of this study is to assess factors associated with lower extremity pain and its impact on preadolescents in a population-based cohort. METHODS: A structured pain questionnaire was completed by 1756 schoolchildren of third and fifth grades to assess musculoskeletal pain, psychosomatic symptoms, subjective disabilities, school absence and frequency of exercise. In addition, hypermobility and physical fitness were measured. RESULTS: The knee was the most common site of pain followed by the ankle-foot and thigh. Of the children who reported pain in their lower extremity, approximately 70% reported at least one disability and 19 % reported school absence attributed to their pain during the previous three-month period. Children with traumatic pain had a higher subjective disability index than those with non-traumatic pain (P = 0.02). Age less than 11 years, headache, abdominal pain, depressive feelings, day tiredness, and vigorous exercise were more common in children with lower limb pain than those free of it. In the stratified analysis, younger age was related to both traumatic and non-traumatic pain groups. Vigorous exercise was positively associated with traumatic pain, while subjects with non-traumatic pain had more frequent psychosomatic symptoms. CONCLUSION: Risk factors and consequences of traumatic and non-traumatic lower limb pain are not similar. Traumatic lower limb pain is associated with practicing vigorous exercise and high level of physical fitness, while non-traumatic pain is more correlated with psychosomatic symptoms. These differences might be one of the reasons for the discrepancy of previous research conclusions. The two conditions need to be treated as different disorders in future studies

The German Young Olympic Athletes' Lifestyle and Health Management Study (GOAL Study): design of a mixed-method study

<p>Abstract</p> <p>Background</p> <p>In order to perform at top levels, elite athletes have to both protect and risk their health at the same time. Adolescent elite athletes have the additional challenge of coping with substantial physical, psychological and social transformations. The contradictory phenomenon of protecting and risking the adolescent athletes' health in sports challenges the development of health promotion and protection strategies. The GOAL Study (German Young Olympic Athletes' Lifestyle and Health Management Study) analyzes the individual and organizational management of health in adolescent elite sports.</p> <p>Methods/design</p> <p>We combine quantitative and qualitative approaches in a mixed-method study. This allows us to gather a broad range of representative information on squad athletes from all Olympic disciplines as well as in-depth information on four selected Olympic disciplines (artistic gymnastics, biathlon, handball and wrestling). Within the quantitative section we attempt to identify the young athletes' health and nutrition behavior, their subjective health state and their lay health representations, health-related social networks, and structures of medical attendance. 1138 national team level athletes born between 1992 and 1995 from 51 Olympic disciplines responded to the questionnaire (response rate: 61,75%). The qualitative section investigates the meaning and relevance of health and nutrition within the athletes' sports specific surroundings, the impact of biographic backgrounds on individual health behavior, and sports specific cultures of health, nutrition and risk. We interviewed 24 athletes and 28 coaching and medical experts, and carried out 14 multi-day participant observations at training sessions and competitions.</p> <p>Conclusions</p> <p>The studies' results will serve as the basis for developing tailored health promotion strategies to be in cooperation with German elite sports associations.</p

Knee stability assessment on anterior cruciate ligament injury: Clinical and biomechanical approaches

Anterior cruciate ligament (ACL) injury is common in knee joint accounting for 40% of sports injury. ACL injury leads to knee instability, therefore, understanding knee stability assessments would be useful for diagnosis of ACL injury, comparison between operation treatments and establishing return-to-sport standard. This article firstly introduces a management model for ACL injury and the contribution of knee stability assessment to the corresponding stages of the model. Secondly, standard clinical examination, intra-operative stability measurement and motion analysis for functional assessment are reviewed. Orthopaedic surgeons and scientists with related background are encouraged to understand knee biomechanics and stability assessment for ACL injury patients