Pectus Excavatum postsurgical outcome based on preoperative soft body dynamics simulation

Pectus excavatum is the most common congenital deformity of the anterior chest wall, in which an abnormal formation of the rib cage gives the chest a caved-in or sunken appearance. Today, the surgical correction of this deformity is carried out in children and adults through Nuss technic, which consists in the placement of a prosthetic bar under the sternum and over the ribs. Alth ough this technique has been shown to be safe and reliable, not all patients have achieved adequate cosmetic outcome. This often leads to psyc hological problems and social stress, before and after the surgical correction. This paper targets this particular problem by presenting a method to predict the patient surgical outcome based on pre-surgical imagiologic information and chest skin dynamic modulation. The proposed approach uses the patient pre-surgical thoracic CT scan and anatomical-surg ical references to perform a 3D segmentation of the left ribs, right ribs, sternum and skin. The technique encompasses three steps: a) approximation of the cartilages, between the ribs and the sternum, trough b-spline interpolation; b) a volu metric mass spring model that connects two layers - inner skin layer based on the outer pleura contour and the outer su rface skin; and c) displacement of the sternum according to the prosthetic bar position. A dynamic model of the skin around the chest wall region was generated, capable of simulating the effect of the movement of the prosthetic bar along the sternum. The results were compared and validated with patient postsurgical skin surface acquired with Polhemus FastSCAN system.Fundação para a Ciência e Tecnologi

An approach to develop sustainable medical devices

Tese de doutoramento BioengenhariaThe development and commercialization of contemporary Medical Devices is inherently of a multidisciplinary nature. Consequently, they have to undergo a stringent regulatory compliance procedure in conformity with an ever increasingly fierce and competitive business environment. Throughout the product life cycle, medical devices would significantly consume renewable as well as non-renewable resources and as a result exert a substantial social, economic and environmental impact(s). Accordingly, it is imperative to consider the criteria of the aforementioned domains of sustainability in the initial phases of product development. The proposed conceptual multifaceted framework comprehensively explores a broader scope of sustainable product development, mainly from the pragmatic standpoint of systems engineering in comparison to the contemporary evaluation and development approaches. The underpinnings of the proposed framework encompasses the critical role of a decision model titled ‘Multi Criteria Hierarchical Model (MCHM)’ which is in fact an extensive revision of the Analytical Hierarchy Process decision modelling approach. The MCHM contains three tiers of pertinent criteria to attain overall sustainability. The structure of MCHM illustrates the tolerable level of sustainability in Tier 1, which is non-negotiable and compulsory, and the additional degrees of sustainability that increases from Tier 2 to Tier 3. Furthermore, the proposed framework elucidates the active participation of the MCHM in product design and development by conjoining with a wide spectrum of technical and conceptual tools. The research methodologies in the thesis are comprised of interviews, questionnaires and case studies that mainly involved active participatory observation. The objective of incorporating case studies in the thesis is to evaluate the effectiveness of the MCHM in an Industrial environment. In this doctoral research the contemporary medical devices explored during the case studies included a wide spectrum of materials and technologies that range from metal and non-metal prosthesis (external and sometimes internal), instruments, advanced implantable devices and biodegradable scaffolds used in regenerative medicine. The research activities commenced with a thorough literature review that directed the researcher to the need for an exploratory study, accomplished by interviews with experts from academia and industry. These experts provided their feedback on the Sustainability related criteria outlined in the MCHM based on their expertise and knowledge of product development in diverse economic circumstances. The feedback was obtained in the form of assigning numerical scores during pair-wise comparison between two criteria at a time. The scores and recommendations were documented for being incorporated within the case studies. In the case studies, the MCHM was incorporated in the early stage of product development to prioritize bare minimum environmental sustainability and profitability in accordance with regulatory compliance. During the decision making process, the product design was investigated in order to simultaneously accomplish the aforementioned facets by way of incorporating the expert recommendations. Furthermore, these expert recommendations obtained in conjunction with business strategies and technical problem solving techniques, such as Case based Reasoning (CBR), Design by Analogy (DA) and Theory of Inventive Problem Solving (TRIZ) were considered for resolving conflicts between the criteria of Tier 1 and other Tiers. The thesis provides decision makers and the product development teams with a framework to gain a more holistic perspective on sustainable product development with respect to policies, technical/non-technical tools and business strategies. The goal is to enable these product development teams to implement pragmatic solutions for ensuring long-term competitiveness and the welfare of the Stakeholders.O desenvolvimento e comercialização de dispositivos médicos contemporâneos é por inerência de natureza multidisciplinar. Consequentemente, estes dispositivos têm que passar por um procedimento de regulamentação rigoroso, num ambiente de negócios cada vez cada vez mais acirrado e competitivo. Durante o ciclo de vida do produto, os dispositivos médicos consomem recursos renováveis, bem como recursos não-renováveis, o que origina impactos sociais, económicos e ambientais significativos. Assim, é imperativo considerar as diferentes dimensões da sustentabilidade nas fases iniciais de desenvolvimento do produto. O modelo conceptual proposto explora exaustivamente um propósito mais amplo de desenvolvimento de produtos sustentáveis, principalmente do ponto de vista pragmático da engenharia de sistemas, em comparação com a avaliação e abordagem contemporânea de desenvolvimento de novos produtos. A abordagem proposta suporta-se no modelo de apoio à decisão intitulado Multi Criteria Hierarchy Model (MCHM), que é uma extensão do modelo Analytical Hierarchy Process (AHP). O MCHM contém três níveis de critérios relevantes para alcançar a sustentabilidade global. A estrutura do MCHM reflete o que é obrigatório e não negociável no nível 1, e ainda a importância crescente dos critérios de sustentabilidade do nível 2 para o nível 3. Além disso, o modelo proposto demonstra a relevância da inclusão do MCHM no design e desenvolvimento do produto em conjunção com um amplo espectro de ferramentas técnicas e conceptuais. As metodologias de investigação incluem entrevistas, questionários e estudo de casos que envolveram, principalmente, a observação ativa. A realização de estudos de caso teve como objetivo avaliar a adequação do MCHM em ambiente industrial. Os dispositivos médicos considerados durante o estudo de casos incluíram uma diversidade de materiais e tecnologias que vão desde próteses metálicas e não-metálicas (externas e internas), instrumentos, implantes e suportes poliméricos biodegradáveis usados em medicina regenerativa. A revisão bibliográfica identificou a necessidade de desenvolver um estudo exploratório, suportado em entrevistas a peritos académicos e industriais. Estes peritos apresentaram a sua opinião relativa aos critérios considerados no MCHM, de acordo com a sua experiência e conhecimento sobre o desenvolvimento de produtos em circunstâncias económicas diversas. A comparação par a par dos critérios permitiu avaliar a sua importância relativa. Os resultados das entrevistas foram documentados para serem incorporados nos estudos de caso. Nos estudos de caso, o MCHM foi incorporado na fase inicial do desenvolvimento de novos produtos para garantir sustentabilidade ambiental e rentabilidade, em concordância com da regulamentação em vigor. Durante o processo de tomada de decisão, o design do produto foi analisado de modo a cumprir simultaneamente os aspetos acima mencionados e incorporar as recomendações dos peritos. Além disso, estas recomendações foram consideradas em conjunto com as estratégias de negócio e técnicas de resolução de problemas técnicos, tais como o Case Based Reasoning (CBR), Design by Analogy (DA) e Theory of Inventive Problem Solving (TRIZ) para a resolução de conflitos entre os critérios do nível 1 e dos outros níveis. A tese proporciona aos decisores e às equipas de desenvolvimento de novos produtos um modelo para obter uma perspectiva mais holística sobre o desenvolvimento de produtos sustentáveis, relativamente às políticas, ferramentas técnicas/não-técnicas e estratégias de negócio. O objetivo é capacitar essas equipas de desenvolvimento de novos produtos para implementar soluções pragmáticas que assegurem a competitividade a longo prazo e o bem-estar dos stakeholders

A Systematic Review and Meta-Analysis of the Incidence of Injury in Professional Female Soccer

The epidemiology of injury in male professional football is well documented and has been used as a basis to monitor injury trends and implement injury prevention strategies. There are no systematic reviews that have investigated injury incidence in women’s professional football. Therefore, the extent of injury burden in women’s professional football remains unknown. PURPOSE: The primary aim of this study was to calculate an overall incidence rate of injury in senior female professional soccer. The secondary aims were to provide an incidence rate for training and match play. METHODS: PubMed, Discover, EBSCO, Embase and ScienceDirect electronic databases were searched from inception to September 2018. Two reviewers independently assessed study quality using the Strengthening the Reporting of Observational Studies in Epidemiology statement using a 22-item STROBE checklist. Seven prospective studies (n=1137 professional players) were combined in a pooled analysis of injury incidence using a mixed effects model. Heterogeneity was evaluated using the Cochrane Q statistic and I2. RESULTS: The epidemiological incidence proportion over one season was 0.62 (95% CI 0.59 - 0.64). Mean total incidence of injury was 3.15 (95% CI 1.54 - 4.75) injuries per 1000 hours. The mean incidence of injury during match play was 10.72 (95% CI 9.11 - 12.33) and during training was 2.21 (95% CI 0.96 - 3.45). Data analysis found a significant level of heterogeneity (total Incidence, X2 = 16.57 P < 0.05; I2 = 63.8%) and during subsequent sub group analyses in those studies reviewed (match incidence, X2 = 76.4 (d.f. = 7), P <0.05; I2 = 90.8%, training incidence, X2 = 16.97 (d.f. = 7), P < 0.05; I2 = 58.8%). Appraisal of the study methodologies revealed inconsistency in the use of injury terminology, data collection procedures and calculation of exposure by researchers. Such inconsistencies likely contribute to the large variance in the incidence and prevalence of injury reported. CONCLUSIONS: The estimated risk of sustaining at least one injury over one football season is 62%. Continued reporting of heterogeneous results in population samples limits meaningful comparison of studies. Standardising the criteria used to attribute injury and activity coupled with more accurate methods of calculating exposure will overcome such limitations