COMBINING MUSCULOSKELETAL MODELING AND FEM IN DIABETIC FOOT PREVENTION

Recently the development of Patient-specific models (PSMs) tailored to patient-specific data, has gained more and more attention in clinical applications. PSMs could represent a solution to the growing awareness of personalized medicine which allow the realization of more effective rehabilitation treatments designed on the subject capabilities. PSMs have the potential of improving diagnosis and optimizing clinical treatments by predicting and comparing the outcomes of different approaches of intervention. Furthermore they can provide information that cannot be directly measured, such as muscle forces or internal stresses and strains of the bones. Given the considerable amount of diseases affecting motor ability, PSMs of the lower limbs have been broadly addressed in literature. Two techniques are mostly used in this area: musculoskeletal (MS) modeling and finite element (FE) analysis. (MS) models represent a valuable tool, as they can provide important information about the unique anatomical and functional characteristics of different subjects, through the computation of human internal variables, such as muscle activations and forces and joint contact forces. The flexibility and adaptability of FE analysis makes it a perfect solution to model biological geometries and materials and to simulate complicated boundary and loading conditions. Accurate and descriptive FE models would serve as an excellent tool for scientific and medical research. Furthermore they could be used in clinical settings if combined with medical imaging, in order to improve patient care. Several 3-dimensional (3D) foot FE models were recently developed to analyze the biomechanical behavior of the human foot and ankle complex that is commonly studied with experimental techniques like stereophotogrammetry, force and plantar pressure plates. In this context, many gait analysis protocols have been proposed to assess the 3D kinetics, kinematics and plantar pressure distribution. This evaluation has shown to be useful in characterizing the foot biomechanics in different pathologies like the diabetic foot. Diabetic foot is an invalidating complication of diabetes mellitus, a chronic disease frequently encountered in the aging population. It is characterize by the development of ulcers which can lead to amputation. Models for simulations of deformations and stresses in the diabetic plantar pad are required to predict high risk areas on the plantar surface and can be used to investigate the performance of different insoles design for optimal pressure relief. This work represents a first effort towards the definition of a more complete PSM which combining both a MS model and a FE model, can increase the understanding of the diabetic foot pathology. To achieve this objective, several limitations and issues have been addressed. As first, MS models of diabetic and control subjects were developed using OpenSim, to estimate muscle forces. The objective was to evaluate whether the diabetic population exhibit lower limb muscle strength deficits compared to the healthy one. Subjects routine gait analysis was performed and lower limb joints kinematics, kinetics, time and space parameters estimated by means of a modified version of the IORgait protocol. 3D lower limb joints kinematics and kinetics was also calculated with OpenSim. Both methodologies were able to highlight differences in joint kinematics and kinetics between the two populations. Furthermore MS models showed significant differences in healthy muscle forces with respect to the diabetic ones, in some of the muscles. This knowledge can help the planning of specific training in order to improve gait speed, balance, muscle strength and joint mobility. After the use of MS models proved to be applicable in the diabetic population, the next step was to combine them with foot FE models. This was done in two phases. At first the impact of applying the foot joints contact forces (JCFs) obtained from MS models as boundary condition on the foot FE models was verified. Subject specific geometries from MRI were used for the development of the foot FE models while the experimental plantar pressures acquired during gait were used in the validation process. A better agreement was found between experimentally measured and simulated plantar pressure obtained with JCFs than with the experimentally measured ground reaction forces as boundary conditions. Afterwards the use of muscles forces as boundary condition in the FE simulations was evaluated. Subject-specific integrated and synchronized kinematic-kinetic data acquired during gait analysis were used for the development of the MS models and for the computation of the muscle forces. Muscle insertions were then located in the MRI and correspondent connectors were created in the FE model. FE subject-specific simulations were subsequently run with Abaqus by conducting a quasi-static analysis on 4 gait cycle phases and adopting 2 conditions: one including the muscle forces and one without. Once again the validation of the FE simulations was done by means of a comparison between simulated and experimentally measured plantar pressures. Results showed a marked improvement in the estimation of the peak pressure for the model that included the muscles. Finally, an attempt towards the definition of a parametric foot finite element model was done. In fact, despite the recent developments, patient-specific models are not yet successfully applied in a clinical setting. One of the challenges is the time required for mesh creation, which is difficult to automate. The development of parametric models by means of the Principle Component Analysis (PCA) can represent an appealing solution. In this study PCA was applied to the feet of a small cohort of diabetic and healthy subjects in order to evaluate the possibility of developing parametric foot models and to use them to identify variations and similarities between the two populations. The limitations of the use of models have also been analyzed. Their adoption is indeed limited by the lack of verification and validation standards. Even using subjects’ MRI or CT data for the development of FEM together with experimentally acquired motion analysis data for the boundary and loading conditions, the subject specifity is still not reached for what regards all the material properties. Furthermore it should be considered that everything relies on algorithm and models that would never be perfectly representing the reality. Overall, the work presented in this thesis represents an extended evaluation of the possible uses of modeling techniques in the diabetic foot prevention, by considering all the limitations introduced as well as the potential benefits of their use in a clinical context. The research is organized in six chapters: Chapter 1 - provides a background on the modeling techniques, both FE modeling and MS modeling. Furthermore it also describes the gait analysis, its instrumentation and some of the protocols used in the evaluation of the biomechanics of the lower limbs; Chapter 2 - gives a detailed overview of the biomechanics of the foot. It particularly focuses on the diabetes and the diabetic foot; Chapter 3 - introduces the application of MSs for the diabetic foot prevention after a brief background on the techniques usually chosen for the evaluation of the motor impairments caused by the disease. Aim, material and methods, results and discussion are presented. The complete work flow is described, and the chapter ends with a discussion on new key findings and limitations. Chapter 4 – reports the work done to combine the use of musculoskeletal models with foot FEMs. At first the impact of applying the foot joints contact forces obtained from MS models as boundary condition on the foot FEMs is verified. Then the use of muscles forces (again obtained from MS models) as boundary condition in the FE simulations is evaluated. For both studies a brief background is presented together with the methods applied, the results obtained and a discussion of novelties and drawbacks. Chapter 5 – explores the possibility of defining a parametric foot FEM applying the Principle Component Analysis (PCA) on the feet of a small cohort of diabetic and healthy subjects. A background on the importance of patient specific models is presented followed by material and methods, results and discussion of what obtained with this study. Chapter 6 - summarizes the results and the novelty of the thesis, delineating the conclusions and the future research paths

Os atletas Paralímpicos Rio 2016 nas redes sociais digitais

The objective of this research was to analyze how the participation of Brazilian Paralympic athletes in the Rio 2016 Games influenced the development of their digital social networks until the Parapan-American Games Lima 2019, focusing specifically on Facebook, Instagram and Twitter. The study was of a quantitative and descriptive nature. The sample included 26 Brazilian athletes. The main findings of the research were that for Paralympic athletes the network that presented the highest growth potential was Facebook. In addition, most participants represent the most popular Paralympic modalities in Brazil: swimming and athletics. It is also noteworthy that athletes with physical disabilities are the most active in social networks when compared with visual and intellectual. The movement of social networks in the context of Paralympic athletes was explored, and considerations that may contribute to the qualification and greater reach of these tools in the Paralympic context as a means of forming a sports culture more qualified.O objetivo dessa pesquisa foi analisar como a participação dos atletas Paralímpicos brasileiros nos Jogos Rio 2016 influenciou o desenvolvimento de suas redes sociais digitais até os Jogos Parapan-Americanos Lima 2019, focando especificamente no Facebook, Instagram e Twitter. O estudo foi de cunho quantitativo e descritivo. Participaram da amostra 26 atletas brasileiros. Os principais achados da pesquisa foram que para os atletas paralímpicos a rede que apresentou maior potencial de crescimento foi o Facebook. Além disso, a maioria dos participantes representa as modalidades Paralímpicas mais populares no Brasil: natação e atletismo. Também se destaca que os atletas com deficiência física são os mais atuantes em redes sociais quando comparados com a deficiência visual e intelectual. Explorou-se o movimento das redes sociais no contexto de atletas paralímpicos e indicou-se considerações que podem contribuir para a qualificação e um maior alcance dessas ferramentas no contexto Paralímpico como meio de formação de uma cultura paradesportiva mais qualificada

Quantitative and qualitative running gait analysis through an innovative video-based approach

Quantitative and qualitative running gait analysis allows the early identification and the longitudinal monitoring of gait abnormalities linked to running-related injuries. A promising calibration- and marker-less video sensor-based technology (i.e., Graal), recently validated for walking gait, may also offer a time- and cost-efficient alternative to the gold-standard methods for running. This study aim was to ascertain the validity of an improved version of Graal for quantitative and qualitative analysis of running. In 33 healthy recreational runners (mean age 41 years), treadmill running at self-selected submaximal speed was simultaneously evaluated by a validated photosensor system (i.e., Optogait-the reference methodology) and by the video analysis of a posterior 30-fps video of the runner through the optimized version of Graal. Graal is video analysis software that provides a spectral analysis of the brightness over time for each pixel of the video, in order to identify its frequency contents. The two main frequencies of variation of the pixel's brightness (i.e., F1 and F2) correspond to the two most important frequencies of gait (i.e., stride frequency and cadence). The Optogait system recorded step length, cadence, and its variability (vCAD, a traditional index of gait quality). Graal provided a direct measurement of F2 (reflecting cadence), an indirect measure of step length, and two indexes of global gait quality (harmony and synchrony index). The correspondence between quantitative indexes (Cadence vs. F2 and step length vs. Graal step length) was tested via paired t-test, correlations, and Bland-Altman plots. The relationship between qualitative indexes (vCAD vs. Harmony and Synchrony Index) was investigated by correlation analysis. Cadence and step length were, respectively, not significantly different from and highly correlated with F2 (1.41 Hz \ub1 0.09 Hz vs. 1.42 Hz \ub1 0.08 Hz, p = 0.25, r2 = 0.81) and Graal step length (104.70 cm \ub1 013.27 cm vs. 107.56 cm \ub1 13.67 cm, p = 0.55, r2 = 0.98). Bland-Altman tests confirmed a non-significant bias and small imprecision between methods for both parameters. The vCAD was 1.84% \ub1 0.66%, and it was significantly correlated with neither the Harmony nor the Synchrony Index (0.21 \ub1 0.03, p = 0.92, r2 = 0.00038; 0.21 \ub1 0.96, p = 0.87, r2 = 0.00122). These findings confirm the validity of the optimized version of Graal for the measurement of quantitative indexes of gait. Hence, Graal constitutes an extremely time- and cost-efficient tool suitable for quantitative analysis of running. However, its validity for qualitative running gait analysis remains inconclusive and will require further evaluation in a wider range of absolute and relative running intensities in different individuals

Estimating Muscle Power of the Lower Limbs through the 5-Sit-to-Stand Test: A Comparison of Field vs. Laboratory Method

The 5-Sit-to-stand test (5STS) is used for lower limb muscle power (MP) determination in field/clinical setting. From the time taken to perform five standing movements and three partially verified assumptions (vertical displacement, mean concentric time, and mean force), MP is estimated as the body's vertical velocity x force. By comparison with a gold standard, laboratory approach (motion capture system and force plate), we aimed to: (1) verify the assumptions; (2) assess the accuracy of the field-estimated MP (MPfield); (3) develop and validate an optimized estimation (MPfield-opt). In 63 older adults (67 +/- 6 years), we compared: (i) estimated and measured assumptions (2-WAY RM ANOVA), (ii) MPfield and MPfield-opt with the reference/laboratory method (MPlab) (2-WAY RM ANOVA, Pearson's correlation coefficient (r), Bland-Altman analysis). There was a significant difference between estimated and measured assumptions (p < 0.001). Following the implementation of the optimized assumptions, MPfield-opt (205.1 +/- 55.3 W) was not significantly different from M-lab (199.5 +/- 57.9 W), with a high correlation (r = 0.86, p < 0.001) and a non-significant bias (5.64 W, p = 0.537). Provided that corrected assumptions are used, 5STS field test is confirmed a valid time- and cost-effective field method for the monitoring of lower limbs MP, a valuable index of health status in aging

Identidade brasileira em transição: O olhar da mídia estrangeira sobre a cerimônia de abertura dos Jogos Olímpicos Rio 2016

The article aims at an investigation of the forms of narration of Brazil’s international image through the Olympic Games Rio 2016. The objective is to extend the knowledge and understanding of narratives upon Brazil and its identity elements which were built abroad in the context of the Olympic Games Rio 2016. Texts from published international newspapers are analyzed as result of the Opening Ceremony. The selection criterion of the periodicals was defined from the participating countries whose official languages were Portuguese, Spanish and or English. The study characterizes itself as a qualitative research, based on bibliographic and documental sources. The analysis showed new identity representations about Brazil, pointing to the presence of new elements, from the reports published by foreign media.O artigo tem como objetivo uma investigação sobre as formas de narração da imagem internacional do Brasil através dos Jogos Olímpicos do Rio 2016. O objetivo é ampliar o conhecimento e a compreensão sobre narrativas sobre o Brasil e seus elementos identitários construídos no exterior no contexto dos Jogos Olímpicos do Rio 2016. São analisados os textos de jornais internacionais publicados como decorrência da Cerimônias de Abertura. O critério de escolha dos periódicos foi definido a partir dos países participantes, que tivessem como idioma português, espanhol ou inglês. O estudo caracteriza-se como uma pesquisa qualitativa, baseada em fontes bibliográficas e documentais. A análise mostrou novas representações identitárias sobre o Brasil, apontando para a presença de novos elementos, a partir das reportagens divulgadas pela mídia estrangeira

Olimpíada Cultural Rio 2016: A percepção dos espectadores dos Jogos Olímpicos

Mega-events are events of short or pre-established duration with large public, financial investment, repercussion and cultural involvement, such as the Olympic Games. Created in antiquity and reestablished by the French Baron Pierre de Coubertin in 1896, the Games have since their idealization not only sporting events but also a program called the Cultural Olympiad, promoting culture through attractions and shows. The objectives of this study are to verify the perception and the involvement of spectators of the Rio 2016 Olympic Games with the Cultural Olympiad. The data were collected from a questionnaire applied to 1233 spectators during the Pentathlon events in the Rio 2016 Games. As a result, spectators questioned about the "amount of information they received about Cultural Olympiad events" reported that received "a lot" (24.8%), "little" (44.8%) and "none" (26.9%) information. When asked if they had "attended any of the Cultural Olympiad events", 39.7% responded positively and 56.8% negatively. The results indicate the need for an evaluation on the dissemination of Cultural Olympiad events, as well as a review of the types of activities proposed for these events.Os megaeventos são eventos de curta ou preestabelecida duração com grande público, investimento financeiro, repercussão e envolvimento cultural, como os Jogos Olímpicos. Criados na antiguidade e reestabelecidos pelo Barão francês Pierre de Coubertin, em 1896, os Jogos tiveram, desde a sua idealização, não somente eventos esportivos, mas também uma programação denominada Olimpíada Cultural, promovendo a cultura através de atrações e espetáculos. Os objetivos desse estudo são verificar a percepção e o envolvimento dos espectadores dos Jogos Olímpicos Rio 2016 com a Olímpiada Cultural. Os dados foram coletados a partir de um questionário aplicado em 1233 espectadores durante os eventos do Pentatlo nos Jogos Rio 2016. Como resultado, os espectadores quando questionados sobre a “quantidade de informação que receberam sobre eventos da Olímpiada Cultural?” relataram que receberam “muita” (24,8%), “pouca” (44,8%) e “nenhuma” (26,9%) informação. Quando questionados se haviam “comparecido a algum dos eventos da Olimpíada Cultural”, 39,7% respondeu positivamente e 56,8% negativamente. Os resultados apontam a necessidade de uma avaliação sobre a divulgação dos eventos da Olimpíada Cultural, bem como, uma revisão dos tipos de atividades propostas para estes eventos

Olympic Values Inventory (IVO): Validation of an instrument for social sports programs

There is an increasing number of social sports programmes in Brazil which use values as an educational tool. In this sense, it is important to have an instrument capable of measuring these programmes efficiency. This paper aims to create and test the metrical principles of Content Validation Coefficient (CVC) of the Olympic Values Inventory through items that embrace the Olympic Values (Friendship, Respect and Excellence). The inventory items elaboration was based on three-dimensional structures, researchers’ previous experiences and bibliographical review about the topic; which resulted in 41 items. To evaluate the CVC, five specialists have participated of the evaluation by analysing the clarity and relevance of each item based on a Likert scale (1 to 5). The results were assessed based on the Content Validation Coefficient calculation (CVCt). The CVCt of the items was sufficient on both Clarity (CVCt= 0,79) and Relevance (CVCt=0,86). Therefore, it is considered that the Olympic Values Inventory is legitimate according to Content Validation

Os e-sports e os Jogos Olímpicos: Perspectivas de um debate em andamento

This literature review paper aims to understand the different perspectives on the inclusion or not of eSports in the Olympic Games programme. ESports (electronic sports) popularity among world’s youth population grows daily. The eSports phenomenon became a new form of entertainment with its own financial means and cultural practices, very close related to streaming technology, and ultimately bringing new questions and challenges for the so-called ‘traditional sports’ field. The audience success sparked the gaming industry with a considerable economic growth, transforming a backyard practice in the beginning of the century into a worldwide recognized activity; a megaevent in terms of infrastructure and media coverage. Therefore, in a short period of time the debate about eSports become recognized as ‘sport’ as well as to be include into the Olympic Games programme emerged. In recent years, some decisions heated this debate. For example, at the occasion of the 6th Summit of the International Olympic Committee (IOC), held at Lausanne (Switzerland) in 2017, eSports were placed on the agenda about the future of the Olympic Movement. As a result of the Summit discussions, the IOC concluded that (1) eSports have been demonstrating a sharp growth with the youth of several countries and could become a platform for engagement between this young population and the Olympic Movement; (2) eSports can be considered a physical activity and the players training intensity could be compared to ‘traditional sports’ athletes; (3) to be recognized as sport by the IOC, the contents of eSports must not violate the Olympic Values; and (4) in order to the IOC grant recognition, an international eSports federation must be created to ensure the compliance of the rules and regulations of the Olympic Movement (IOC, 2017). Moreover, another important milestone was the announcement of the Intel World Open, an eSports event organized by Intel in partnership with the IOC that is going to be held in July 2020 and it will be a pre-event for the Tokyo Olympic Games. In this sense, this paper has an exploratory approach and the Content Analysis was the interpretational method used. The main results indicated three categories of understanding about the eSports and the Olympics relation: (1) the eSports does not have the necessary features to be considered ‘sport’, then could not be included in Olympic programme; (2) the eSports activity is comparable to ‘traditional sports’, therefore could be part of the Olympic programme; and (3) the eSports could have its own ‘Olympic event’, a parallel competition such as Paralympics. In this sense, the relationship between the eSports and the Olympic Movement is undeniable and despite the different arguments analysed in paper, there are other perspectives remaining to be considered. Thus, a second phase of this study is currently under development and it includes the eSports and Olympics protagonists point of view about the research topic

Advanced Robotic Therapy Integrated Centers (ARTIC): an international collaboration facilitating the application of rehabilitation technologies

Background: The application of rehabilitation robots has grown during the last decade. While meta-analyses have shown beneficial effects of robotic interventions for some patient groups, the evidence is less in others. We established the Advanced Robotic Therapy Integrated Centers (ARTIC) network with the goal of advancing the science and clinical practice of rehabilitation robotics. The investigators hope to exploit variations in practice to learn about current clinical application and outcomes. The aim of this paper is to introduce the ARTIC network to the clinical and research community, present the initial data set and its characteristics and compare the outcome data collected so far with data from prior studies. Methods: ARTIC is a pragmatic observational study of clinical care. The database includes patients with various neurological and gait deficits who used the driven gait orthosis Lokomat® as part of their treatment. Patient characteristics, diagnosis-specific information, and indicators of impairment severity are collected. Core clinical assessments include the 10-Meter Walk Test and the Goal Attainment Scaling. Data from each Lokomat® training session are automatically collected. Results: At time of analysis, the database contained data collected from 595 patients (cerebral palsy: n = 208; stroke: n = 129; spinal cord injury: n = 93; traumatic brain injury: n = 39; and various other diagnoses: n = 126). At onset, average walking speeds were slow. The training intensity increased from the first to the final therapy session and most patients achieved their goals. Conclusions: The characteristics of the patients matched epidemiological data for the target populations. When patient characteristics differed from epidemiological data, this was mainly due to the selection criteria used to assess eligibility for Lokomat® training. While patients included in randomized controlled interventional trials have to fulfill many inclusion and exclusion criteria, the only selection criteria applying to patients in the ARTIC database are those required for use of the Lokomat®. We suggest that the ARTIC network offers an opportunity to investigate the clinical application and effectiveness of rehabilitation technologies for various diagnoses. Due to the standardization of assessments and the use of a common technology, this network could serve as a basis for researchers interested in specific interventional studies expanding beyond the Lokomat®