Search

The Tibial Tuberosity Advancement (TTA) surgical technique is used in veterinary surgery to limit cranial tibial translation during canine gait, lengthening the lever arm of the quadriceps in Anterior Cruciate Ligament-deficient (ACL-deficient) stifle joints. It is know that after TTA, the patellofemoral pressure decreases, but the Patellar Tendon (PT) behavior has not been observed experimentally yet. This study measures the PT force under caudal femoral drawer at knee flexion angles from 135° to 90° in intact and pathological knee to asses the effect of TTA on the tendon. Five fresh cadaveric adult canine stifle joint were tested in an apparatus in which muscle forces of the canine hind limb were simulated. Each knee was tested in three different conditions: intact, ACL-deficient and with TTA. PT force was measured using a electrical transducer. The greater the joint flexion angles, the greater the PT force. The knee average force of the five specimens in 90º flexion were 28.4 ± 3.2 Newtons (N) for the intact, 28.2 ± 3.4 N for the ACL-deficient and 24.9 ± 2 N for the TTA knee, which decreased compared to the healthy knee, so TTA generates a loosening of the PT force. The PT force showed a fast rate of change in the operated knee because of a shift in the pattern of knee flexion, so the biomechanics of the entire joint could be influenced by the TTA technique. La técnica quirúrgica de avance de la tuberosidad tibial (ATT) es usada en cirugía veterinaria para limitar la translación craneal de la tibia durante la marcha canina, alargando el brazo de palanca del cuádriceps, en articulaciones de rodilla con ligamento cruzado anterior (LCA) deficiente. Es conocido que después a la intervención de la ATT, la presión patelofemoral disminuye, pero el comportamiento del Tendón Patelar (TP) aún no ha sido observadobajo experimentación. Este estudio mide la fuerza del TP bajo una fuerza femoral caudal a unos ángulos de flexión de la rodilla de 135° a 90° en rodilla intacta y dañada para determinar el efecto de la ATT sobre el tendón. Cinco articulaciones de rodilla canina refrigeradas fueron ensayadas en un banco de ensayos, en el cual se simularon las fuerzas musculares de la extremidad trasera canina. Cada rodilla fue probada en tres condiciones: intacta, con LCA deficiente y con la ATT. La fuerza del TP se midió usando transductores eléctricos. A mayores ángulos de flexión, mayor fue la fuerza sobre el TP. Las fuerzas medias de las rodillas en los cinco especímenes en flexión de 90º fueron, 28,4 ± 3,2 Newtons (N) para la intacta, 28,2 ± 3,4 N para el LCA deficiente y 24,9 ± 2 N para la ATT, la cual disminuye comparada con la rodilla sana, lo que muestra que la TTA genera un aflojamiento en la fuerza del TP. La fuerza del TP tiene un porcentaje de cambio mayor en la rodilla con la ATT, debido a cambios en el comportamiento de flexión de la rodilla, por lo que la biomecánica de la articulación al completo podría estar influenciada por dicha técnica. elsa.perez@upc.edu

Objective Our objective was to compare the peak vertical force (PVF) and vertical impulse (VI) between dogs with cranial cruciate ligament disease and a tibial plateau angle (TPA) greater or less than 25 degrees.Methods A retrospective study was performed in 18 dogs with cranial cruciate ligament disease in which kinetic gait data were obtained with a pressure walkway system. Dogs were distributed in two groups: dogs with a TPA ≤ 25 degrees (n = 8) and dogs with a TPA > 25 degrees (n = 10). Mean PVF and VI in per cent of body weight (%BW) were compared between groups with an unpaired t-test (p Results Mean PVF and VI for the cranial cruciate ligament disease limb were 14.39%BW and 3.57%BWs for dogs with a TPA >25 degrees and 14.44%BW and 3.47%BWs for dogs with a TPA ≤ 25 degrees. There was no significant difference in mean PVF and VI between the groups.Conclusion The results suggest that there is no difference in kinetic data between dogs with cranial cruciate ligament disease and a TPA greater or less than 25 degrees. Other factors such as body weight, time of injury or meniscal lesion could be more related to the magnitude of cranial cruciate ligament disease lameness.

Resumen El mundo actual y las tendencias de universalización de procesos que se dan a través de la globalización, la apertura de mercados, la internacionalización, la competencia y todas las nuevas situaciones que el desarrollo empresarial trae día a día hacen que los procesos empresariales deban ser más eficientes y eficaces, con lo cual existen riesgos asociados con las actividades que implican un sobre esfuerzo físico y por ende una posible lesión osteomuscular. Objetivo. Analizar las relaciones existentes entre las tareas de impacto negativo y las variables ergonómicas asociadas a la manipulación de cargas, a través del uso de las herramientas de evaluación REBA y RULA de manera que se identifiquen los factores de riesgo por parte de los trabajadores de Drilling & Well Services, especialmente cuñeros y encuelladores de una empresa petrolera. Materiales y métodos. La investigación es de tipo descriptivo, pues representa un análisis experimental que tiene como objetivo establecer las condiciones iniciales y determinar la manera como se manifiesta una determinada circunstancia particular identificando los rasgos característicos de la operación. Resultados. Se evidenciaron actividades como el levantar y posicionar la cuña, trasladar la tubería de perforación, soltar o ajustar las llaves de potencia y ajustar los brazos de los elevadores para cerrarlos y con ello asegurar la tubería de perforación, como las acciones de riesgo más importantes en las operaciones de los cuñeros y operadores. Abstract The current world and the tendencies of universalization of processes that occur through globalization, the opening of markets, internationalization, competition and all the new situations that business development brings every day make processes must be more efficient and risks, with which there are risks associated with activities that involve physical exertion and therefore a possible musculoskeletal injury. Objective. Analyze the relationships identified between the negative impact tasks and the ergonomic variables associated with cargo handling, by using the REBA and RULA assessment tools so that risk factors are identified by Drilling & Well workers Services, especially wedges and pollsters of an oil company. Materials and methods. The research is descriptive, since it represents an experimental analysis that aims to establish the initial conditions and determine the way in which a particular circumstance is manifested by identifying the characteristic features of the operation. Results. There were activities such as lifting and positioning the wedge, moving the drill pipe, releasing or adjusting the power keys and adjusting the arms of the elevators to close and with it controlling the drill pipe, as the most important risk actions in the operations of the wedges and operators.

Resumen La amputación transtibial provoca una disminución de la información somatosensorial disponible para el sistema nervioso central, esta pérdida muscular y fisiológica que involucra la articulación del tobillo reduce la fuerza muscular de las piernas, lo que afecta la capacidad de equilibrio y la movilidad de quien la sufre, al presentarse bajo uso de las extremidades inferiores, se provoca una hipotrofia de los músculos y el déficit en su fuerza incrementa. Adicionalmente, los sujetos con amputación transtibial deben adaptarse a la falta de la articulación fisiológica del tobillo y los músculos flexores plantares, partes indispensables para una adecuada movilidad articular, fuerza muscular y capacidad de ajuste activo de la prótesis durante la postura estática de bipedestación. Así, se observa que la reducción de la fuerza muscular está asociada con la disminución del equilibrio. El objetivo de la investigación fue analizar el Centro de Presión (cop) para conocer el comportamiento de la estabilidad en una muestra que consistía de sujetos amputados. Se estudió el análisis armónico de señales de la estabilidad en personas amputadas transtibialmente y usuarios de prótesis, esto con el fin de conocer el comportamiento del centro de presión en dicho conjunto de gente. Dos grupos, cada uno de nueve individuos, fueron analizados: un grupo control de no amputados y un grupo de amputados. Se empleó el periodograma vía método de Welch para hallar las componentes frecuenciales propias del centro de presión bajo cada pie con el fin de caracterizarlas y permitir su detección, y así poder entender las diferencias existentes entre los grupos estudiados. En el presente trabajo se muestra el análisis armónico de la señal no estacionaria, y se argumenta que esta es una ayuda considerable en el análisis de la estabilidad. Los resultados indican que la amputación incide en la Densidad Espectral de Potencia (dep), ya que existe diferencia entre las frecuencias del lado amputado y el no amputado (mayor oscilación en el lado amputado, eje antero-posterior); igual situación se presenta entre los dos grupos evaluados (mayor potencia en los amputados en todas las condiciones de la prueba). Abstract Transtibial amputations reduce the amount of somatosensorial information available to the central nervous system. This muscular and physiological loss involving the ankle joint reduces the muscle strength of the legs, which affects the balance and mobility of those who suffer from it. As lower limbs are used less, muscle hypertrophy occurs and the muscle strength deficit increases. Additionally, transtibial amputees should adapt themselves to the lack of a physiological joint between the ankle and the plantar flexor muscles, which are essential for an adequate joint mobility, muscle strength, and active adjustment capacity of the prosthesis during quiet stance. Thus, the reduction of their muscle strength is associated with compromised balance. This study analyzed the Center of Pressure (COP) of a group of transtibial amputees to understand the behavior of their stability. A harmonic analysis of the stability signs of such amputees (prosthesis users) was examined in order to reveal the behavior of their center of pressure. We analyzed two groups of 9 participants each: non-amputee control group and amputees. We used a periodogram, via Welch’s method, to find the frequential components of the center of pressure under each foot in order to characterize and detect them and understand the differences between the study groups. This paper presents the harmonic analysis of a nonstationary signal and supports the idea that the latter is an important tool for stability analysis. The results indicate that amputations have an influence on Power Spectral Density (DEP) because there is a difference in frequencies between the amputated and the non-amputated limb (greater oscillation on the amputated side, antero-posterior axis). The same situation occurred between the study groups (greater power in amputees under all testing conditions).

Background Muscle fatigue is characterized by a decrease in muscle performance, accompanied by an increase in perceived exertion to produce a desired amount of force. The duration of the fatigue effects is not completely clear regarding postural sway and force production in athletes. Research question What is the effect of a specific fatigue protocol in postural sway and force production in female handball athletes and the recovery time necessary for these variables? Methods Twenty female handball athletes participated in this study. Specific handball actions composed the fatigue protocol in the format of a circuit with the gradual increment of laps. They stood upright in one-leg posture on a force plate. For the maximum propulsion force (FMAX), they performed a countermovement jump on the force plate. The center of pressure (COP) and the FMAX were obtained at baseline, immediately after the exhaustion due to the fatigue protocol and every minute during the first 10 min of the recovery phase. Results The FMAX decreased ∼9.5% after the fatigue protocol, whereas de COP area increased 224%. During the recovery phase, the FMAX and the COP area returned to baseline values after five minutes. Significance The first five minutes immediately after the fatigue protocol represent the time interval where the fatigue effects are still present. Future studies willing to investigate the effects of fatigue in athletes should perform the analysis within this short time-window.

Las escuelas osteomusculares son estrategias de intervención específicas que facilitan las acciones preventivas concretas para disminuir el riesgo biomecánico que se presenta en diferentes instituciones. El presente estudio se ejecuta en el puesto de trabajo de mantenimiento en la Plaza Minorista de Medellín, donde se realiza una caracterización inicial de los riesgos biomecánicos, debido a posturas forzadas y sobre esfuerzos, así como a la manipulación manual de cargas. Se utiliza la metodología de evaluación ergonómica, CENEA, con la cual se cuantifica el riesgo en general. Se obtiene como resultados, que los principales riesgos son los biomecánicos, el uso de herramientas y la manipulación manual de cargas. A partir de esto, se establecen temas puntuales para generar una capacitación específica para los operadores de mantenimiento.

In military life, load carriage is an unavoidable part of field operations which is the reason why soldiers often make use of a military backpack. Infantry soldiers usually carry loads weighting more than 30% of their body weight. When the soldier carries a certain weight, his energy expenditure increases, which causes a reduction in performance. The transported load has a movement similar to the vertical displacement of the center of mass of the soldier while walking. This leads to a significant increase in the acceleration forces generated by the action of said load on the body which explains the increase in energy expenditure. The objective of this project was to develop a load carriage system that suspends the load and reduces its vertical displacement. Results show a reduction in both the vertical excursion of the load and in the total vertical ground reaction force when carrying a load with the developed prototype, with respect to the conventional military backpack. RESUMEN En la vida militar, el transporte de cargas es una actividad inevitable durante operaciones de campo, razón por la cual los soldados hacen uso de un morral militar. Los soldados de infantería generalmente transportan cargas mayores al 30% de su peso corporal. Cuando el soldado transporta una carga, su gasto energético aumenta lo que ocasiona una reducción en su rendimiento. La carga transportada tiene un movimiento similar al desplazamiento vertical del centro de masa del soldado durante la marcha. Esto conlleva a un aumento significativo de las fuerzas de aceleración generadas por la acción de la carga sobre el cuerpo lo que explica el aumento del gasto energético. El objetivo del proyecto fue desarrollar un sistema de transporte de carga que la mantenga suspendida para así reducir su desplazamiento vertical. Los resultados muestran una reducción tanto en la excursión vertical como en la fuerza vertical total de reacción del suelo al transportar una carga con el prototipo desarrollado, respecto al morral militar convencional.

Background. The study of the deformation of curved rods subjected to bending and its associated stress state is a complex task that has not been treated in depth in the literature, which makes difficult to obtain constitutive models or Finite Element Models (FEM) in which it is necessary to know all the components of the stress and strain tensors. Objectives. This study focuses on a new calculation methodology to obtain stress and strain tensors of curved rods under bending. Methods. The stress and strain tensors have been determined based on the theory of continuum mechanics and differential geometry of curves (moving bases), in a general methodology and valid for large strains, curved geometries and variable cross-sections along the specimen. This has been applied to the human rib and, in addition, a new experimental method for bending of curved specimens based on Digital Image Correlation (DIC) is presented. Results. Both the test method and the proposed calculations applied to the human rib show results according to expectations, allowing to know the rib curvature changes along the test, the stresses and strains along the rib and the components of both stress and strain in all directions, in order to build the stress and strain tensors. In addition, the results of stress, strain and young’s modulus correspond to those of previous literature in tensile testing of human rib cortical bone. Conclusions. The proposed calculations allow the construction of the strain and stress tensors of a curved specimen subjected to bending, which is of great importance for the development of constitutive models. Moreover, since with this method it is possible to calculate both tensors along the entire length of the specimen and in all directions, it is possible to apply this method in finite element models. Finally, the new test methodology allows to know the stress and strain in curved specimens such as the human rib, from bending tests.

Dorsal laminectomy is routinely performed for spinal cord compressions or stenosis of the cervical vertebral canal. However, despite good results, relevant complications have been described in dogs. Considering the incomplete understanding of the necessity for complementary surgical stabilization after performing laminectomies in the cervical region, this study compared the resistance and range of motion (ROM) of the cervical spinal column subjected to Funkquist B laminectomy between the sixth and seventh vertebrae in dogs. Forty-four cervical vertebral columns (C2-T1) of dogs, with an average weight of 26.2±3.8 kg, were selected using radiography and computed tomography. Four experimental groups (n=11) were established according to the mechanical test: two control groups (flexion and extension control) and two laminectomy groups (flexion and extension laminectomies). Numerical results of the maximum load for measuring the resistance and ROM of the columns of the two control groups and the two laminectomy groups were compared. The laminectomy groups showed a lower maximum load, regardless of the mechanical test performed (P

The aim of this paper is to review the recent evolution of additive manufacturing (AM) within the medical field of preoperative surgical planning. The discussion begins with an overview of the different techniques, pointing out their advantages and disadvantages as well as an in-depth comparison of different characteristics of the printed parts. Then, the state-of-the-art with respect to preoperative surgical planning is presented. On the one hand, different surgical planning prototypes manufactured by several AM technologies are described. On the other hand, materials used for mimicking different living tissues are explored by focusing on the material properties: elastic modulus, hardness, etc. As a result, doctors can practice before performing surgery and thereby reduce the time needed for the operation. The subject of patient education is also introduced. A thorough review of the process that is required to obtain 3D printed surgical planning prototypes, which is based on different stages, is then carried out. Finally, the ethical issues associated with 3D printing in medicine are discussed, along with its future perspectives. Overall, this is important for improving the outcome of the surgery, since doctors will be able to visualize the affected organs and even to practice surgery before performing it.

Introdução: A correta ativação da musculatura estabilizadora do tronco é essencial em diversas situações, inclusive prevenção e tratamento de lombalgias. A ativação adequada desses músculos é um princípio do Método Pilates, porém nem todos os efeitos das variações dos exercícios estão descritos da literatura. Objetivo: comparar a atividade elétrica de músculos do power house (reto abdominal, oblíquo externo, oblíquo interno/transverso abdominal e multífido) durante a execução do exercício Leg Circles no aparelho Cadillac com mola alta e com mola baixa. Métodos: Foram selecionadas 10 instrutoras de Pilates, 30 anos (±5), 58 Kg (±7), estatura 163 cm (±7) que foram submetidas a testes de contrações isométricas voluntárias máximas, e logo após, à realização do Leg Circles no Cadillac com a mola alta e baixa. Foi coletada a atividade elétrica dos músculos reto abdominal, oblíquo interno/transverso abdominal, oblíquo externo e multífido. Resultados: A ativação do oblíquo interno foi maior na mola alta (p=0,002), assim como a ativação do multífido (p=0,042). Já o oblíquo externo foi mais ativado na mola baixa (p=0,001). O reto abdominal não variou sua ativação (p=0,375). Conclusão: A mola alta pode ser acatada como a posição mais adequada para ativar a musculatura profunda do tronco, visto que nesta situação houve maior ativação do multífido e do oblíquo interno/transverso abdominal, somados à menor ativação do oblíquo externo e a baixa ativação no reto abdominal encontrados na situação com mola alta. ABSTRACT. Leg circles on Cadillac: effect of different spring positions on the activation of stabilizers in the trunk. Background: The correct activation of the trunk stabilizing muscles is essential in several situations, including prevention and treatment of low back pain. Proper activation of these muscles is a principle of the Pilates Method, but not all the effects of exercise variations are described in the literature. Objective: compare the electric activity of power house muscles (rectus abdominis, external oblique, internal oblique/transverse abdominal and multifidus) during the execution of the Leg Circles exercise with high spring and low spring in Cadillac apparatus. Methods: Ten Pilates instructors were selected, with 30 years (±5), 58 kg (±7), 163 cm (±7) who underwent maximum voluntary isometric contraction tests before the execution of the Leg Circles on the Cadillac, with high and low spring. The electrical activity of the rectus abdominis, internal oblique/transverso abdominal, external oblique and multifidus muscles was collected. Results: The internal oblique (p=0,002) and the multifidus (p=0,042) activations were greater on the high spring. However, the external oblique showed a higher activation on the lower spring (p = 0.001). The abdominal rectus did not change its activation = 0.375). Conclusion: The high spring can be considered as the most suitable position to ac-tivate the deep musculature of the trunk, since the greater activation of the multifidus and of the internal oblique/transverse abdominal, together with the lower activation of the external oblique and the low acti-vation in the rectus abdominus found in the high spring situation.

This scoping review aims to identify the clinical considerations and orthodontics biomechanics of applying the orthodontic traction approach to transmigrated mandibular canines. The search strategy followed the PRISMA for scoping reviews and was based on six databases, Cochrane C.R.C. Trials, BVS, PubMed (NLM), Google Scholar, Web of Science, and SCOPUS, and included articles published as recently as February 2021. The records had to identify lower canines traction protocols and outcomes. The publications obtained had to meet criteria for the structure of the research and bibliography. The search included combinations of the keywords lower canine, cuspid, and transmigration, along with the terms biomechanics and scoping review in the databases. Only after a consensus of the three reviewers had been reached were the articles retrieved. When a transmigrated lower canine has already erupted, orthodontics biomechanics traction begins by bonding tooth buttons and/or bracket prescriptions: MBT 0.022” x 0.028”, Roth 0.018” x 0.022”, and/or Beggs rectangular arches, ligatures, and elastics. Surgical interventions may be added. The treatment time varied from 22 months to 3.6 years. The final occlusal relationships were satisfactory and did not cause damage to the surrounding tissues. Among the selected articles, the orthodontic biomechanics showed the complexity of the movements. An appropriate occlusion and stability were achieved. Failures in the approach were also found. The clinical considerations show this approach to be viable but to have inherent risks, which include the proximity of the canines to the lower incisor roots. Esta revisión de alcance tiene como objetivo identificar las consideraciones clínicas y la biomecánica de la ortodoncia de la aplicación del enfoque de tracción ortodóncica a los caninos mandibulares transmigrados. La estrategia de búsqueda siguió el PRISMA para las revisiones de alcance y se basó en seis bases de datos, Cochrane C.R.C. Ensayos, BVS, PubMed (NLM), Google Scholar, Web of Science y SCOPUS, e incluían artículos publicados tan recientemente como enero de 2021. Los registros tenían que identificar los protocolos y resultados de tracción de los caninos inferiores. Las publicaciones obtenidas debían cumplir criterios de estructura de la investigación y bibliografía. La búsqueda incluyó combinaciones de las palabras clave canino inferior, canino y transmigración, junto con los términos biomecánica y revisión de alcance en las bases de datos. Solo después de que se alcanzó un consenso de los tres revisores se recuperaron los artículos. Cuando un canino inferior transmigrado ya ha estallado, la tracción biomecánica de ortodoncia comienza uniendo botones dentales y / o prescripciones de brackets: MBT 0.022” x 0.028”, Roth 0.018”x 0.022” y / o arcos rectangulares, ligaduras y elásticos Beggs. Se pueden agregar intervenciones quirúrgicas. El tiempo de tratamiento varió de 22 meses a 3,6 años. Las relaciones oclusales finales fueron satisfactorias y no causaron daño a los tejidos circundantes. Entre los artículos seleccionados, la biomecánica ortodóntica mostró la complejidad de los movimientos. Se logró una adecuada oclusión y estabilidad. También se encontraron fallas en el enfoque. Las consideraciones clínicas muestran que este enfoque es viable pero tiene riesgos inherentes, que incluyen la proximidad de los caninos a las raíces de los incisivos inferiores. Esta revisão objetiva identificar as considerações clínicas e a biomecânica ortodôntica da aplicação da abordagem de tração ortodôntica em caninos inferiores transmigrados. A estratégia de busca seguiu o PRISMA para análises de escopo e foi baseada em seis bancos de dados, Cochrane C.R.C. Trials, BVS, PubMed (NLM), Google Scholar, Web of Science e SCOPUS, e artigos incluídos publicados até janeiro de 2021. Os registros tiveram que identificar protocolos e resultados de tração de caninos inferiores. As publicações obtidas obedeceram a critérios de estruturação da pesquisa e bibliografia. A pesquisa incluiu combinações das palavras-chave canino inferior, cúspide e transmigração, juntamente com os termos biomecânica e revisão de escopo nos bancos de dados. Somente depois que um consenso dos três revisores foi alcançado, os artigos foram recuperados. Quando um canino inferior transmigrado já irrompeu, a tração biomecânica ortodôntica começa com a colagem de botões dentais e / ou prescrições de braquetes: MBT 0,022” x 0,028”, Roth 0,018” x 0,022” e / ou arcos retangulares de Beggs, ligaduras e elásticos. Intervenções cirúrgicas podem ser adicionadas. O tempo de tratamento variou de 22 meses a 3,6 anos. As relações oclusais finais foram satisfatórias e não causaram danos aos tecidos circundantes. Dentre os artigos selecionados, a biomecânica ortodôntica mostrou a complexidade dos movimentos. Uma oclusão e estabilidade adequadas foram alcançadas. Falhas na abordagem também foram encontradas. As considerações clínicas mostram que essa abordagem é viável, mas tem riscos inerentes, que incluem a proximidade dos caninos às raízes dos incisivos inferiores.

Este trabalho apresentou como objetivo geral analisar a influência de diferentes fatores na manutenção da interface cônica interna pilar/implante. Os objetivos específicos foram avaliar o efeito do indexador hexagonal interno no selamento microbiológico da interface cone Morse; o efeito do indexador hexagonal interno da resistência mecânica de implantes cone Morse; o efeito do carregamento axial na variação de deformação na região cervical de implantes cone Morse de diferentes diâmetros, por meio de extensometria; o efeito do carregamento axial na deformação cervical e deslizamento do pilar por meio de medição tridimensional; a interface cone Morse antes e após carregamento axial, por meio de microscopia; e a distribuição de tensões em modelos tridimensionais de implantes cone Morse montados com pilares de parafuso passante. De acordo com os resultados obtidos nos estudos pode-se concluir que o diâmetro influenciou a deformação nas paredes externa e interna na região cervical de implantes cone Morse; a presença de indexador protético no fim do cone interno de implantes cone Morse não influenciou na infiltração bacteriana sob carregamento estático; a presença de indexador protético no fim do cone interno de implante cone Morse não reduziu a sua resistência à fratura; um milhão de ciclos de fadiga com carga aplicada axialmente fora do longo eixo do implante não influenciou negativamente a integridade de implante cone Morse montado com componente protético de parafuso passante. The general aim of this study was to evaluate the conical interface of pilar/implant. The specific aims were to evaluate the influence of hexagonal internal index in the microleakage and mechanical strength of Morse taper implants; the effect of axial loading on the deformation in cervical region of Morse taper implants of different diameters through strain gauge; the effect of axial loading in cervical deformation and sliding of abutment into the implant by tridimensional measurements; the integrity of conical interface before and after dynamic loading by microscopy and microleakage; and the stress distribution in tridimensional finite element models of Morse taper implants assembled with 2 pieces abutment. According to the obtained results, could be concluded that the diameter had influence in the cervical deformation of Morse taper implants; the presence of internal hexagonal index in the end of internal cone of implant didn´t influenced the bacterial microleakage under static loading neither reduced the mechanical strength of implants; one million cycles of vertical and off-center load had no negative influence in Morse taper implant integrity. Tese (Doutorado)

Background: Chronic ankle instability (CAI) is a condition defined by certain structural and functional deficits in the ankle joint complex after acute ankle injury. These deficits include pathological joint laxity, impaired postural control, and decreased strength and neuromuscular control. Purpose: To compare an eyes-open versus an eyes-closed balance training protocol in professional soccer players with CAI. Study Design: Cohort study; Level of evidence, 2. Methods: For this study, we evaluated 19 players from 2 professional soccer teams in Madrid, Spain, all of whom had CAI. Participants from both teams were randomly assigned to an eyes-open group (n = 9) or eyes-closed group (n = 10). All participants completed 4 weeks of a supervised exercise protocol consisting of 3 sessions per week. Members of both the eyes-open and eyes-closed groups performed the same exercise protocol in the same order of execution. At the end of the protocol, the participants were assessed for pain (visual analog scale), ankle dorsiflexion range of motion (weightbearing lunge test), dynamic stability (Star Excursion Balance Test), and fear of movement and reinjury (Tampa Scale for Kinesiophobia). We compared results both before and after balance training and between the eyes-open and eyes-closed balance training groups. Results: Statistically significant differences were found for all of the assessed variables before and after balance training. No statistically significant differences were found between the eyes-closed and eyes-open groups on any variable. Conclusion: In the current study, eyes-closed balance training was not more effective than eyes-open balance training for CAI in professional soccer players.

[Abstract] Optical motion capture is currently the most popular method for acquiring motion data in biomechanical applications. However, it presents a number of problems that make the process difficult and inefficient, such as marker occlusions and unwanted reflections. In addition, the obtained trajectories must be numerically differentiated twice in time in order to get the accelerations. Since the trajectories are normally noisy, they need to be filtered first, and the selection of the optimal amount of filtering is not trivial. In this work, an extended Kalman filter (EKF) that manages marker occlusions and undesired reflections in a robust way is presented. A preliminary test with inertial measurement units (IMUs) is carried out to determine their local reference frames. Then, the gait analysis of a healthy subject is performed using optical markers and IMUs simultaneously. The filtering parameters used in the optical motion capture process are tuned in order to achieve good correlation between the obtained accelerations and those measured by the IMUs. The results show that the EKF provides a robust and efficient method for optical system-based motion analysis, and that the availability of accelerations measured by inertial sensors can be very helpful for the adjustment of the filters. This work was funded by the Spanish MCI under project PGC2018-095145-B-I00, co-financed by the EU through the EFRD program, and by the Galician Government under grant ED431C2019/29. Moreover, F. Michaud would like to acknowledge the support of the Spanish MCI by means of the doctoral research contract BES-2016-076901, co-financed by the EU through the ESF program Xunta de Galicia; ED431C2019/29

Fused filament fabrication (FFF) 3D printing technology allows very complex parts to be obtained at a relatively low cost and in reduced manufacturing times. In the present work, the effect of main 3D printing parameters on roughness obtained in curved surfaces is addressed. Polylactic acid (PLA) hemispherical cups were printed with a shape similar to that of the acetabular part of the hip prostheses. Different experiments were performed according to a factorial design of experiments, with nozzle diameter, temperature, layer height, print speed and extrusion multiplier as variables. Different roughness parameters were measured—Ra, Rz, Rku, Rsk—both on the outer surface and on the inner surface of the parts. Arithmetical mean roughness value Ra and greatest height of the roughness profile Rz are usually employed to compare the surface finish among different manufacturing processes. However, they do not provide information about the shape of the roughness profile. For this purpose, in the present work kurtosis Rku and skewness Rsk were used. If the height distribution in a roughness profile follows a normal law, the Rku parameter will take a value of 3. If the profile distribution is symmetrical, the Rsk parameter will take a value of 0. Adaptive neural fuzzy inference system (ANFIS) models were obtained for each response. Such models are often employed to model different manufacturing processes, but their use has not yet been extended to 3D printing processes. All roughness parameters studied depended mainly on layer height, followed by nozzle diameter. In the present work, as a general trend, Rsk was close to but lower than 0, while Rku was slightly lower than 3. This corresponds to slightly higher valleys than peaks, with a rounded height distribution to some degree. This research was co-financed by the European Union Regional Development Fund within the framework of the ERDF Operational Program of Catalonia 2014–2020 with a grant of 50% of total cost eligible, project BASE3D, grant number 001-P-001646.

Analysis of locomotion is often used as a measure for impairment and recovery following experimental peripheral nerve injury. Compared to rodents, sheep offer several advantages for studying peripheral nerve regeneration. In the present study, we compared for the first time, two-dimensional (2D) and three-dimensional (3D) hindlimb kinematics during obstacle avoidance in the ovine model. This study obtained kinematic data to serve as a template for an objective assessment of the ankle joint motion in future studies of common peroneal nerve (CP) injury and repair in the ovine model. The strategy used by the sheep to bring the hindlimb over a moderately high obstacle, set to 10% of its hindlimb length, was pronounced knee, ankle and metatarsophalangeal flexion when approaching and clearing the obstacle. Despite the overall time course kinematic patterns about the hip, knee, ankle, and metatarsophalangeal were identical, we found significant differences between values of the 2D and 3D joint angular motion. Our results showed that the most apparent changes that occurred during the gait cycle were for the ankle (2D-measured STANCEmax: 157±2.4 degrees vs. 3D-measured STANCEmax: 151±1.2 degrees; P

Background: The aim of this review is to provide a comprehensive overview of the technological state-of-the-art of exosuits and the clinical results obtained when applied to users with mobility impairment. Methods: Searches are carried out in the COCHRANE, PubMed, IEEE Xplore and MEDLINE databases. Titles, abstracts and full texts are screened for inclusion criteria. Technological and clinical data are extracted. The quality of the studies is evaluated via a study quality assessment tool. Results: 19 studies are identified as relevant. Active (47%) and passive exosuits (53%) are used. Most are used untethered (84%), accommodating the demand of mobility. No study reports power consumption, which is important for dimensioning power systems. Fields of applications are post-stroke (79%), osteoarthritis (16%) and post-trauma (5%). Mostly the ankle joint is addressed (57%), while less studies address multiple joints (21%). The outcomes of clinical evaluations of lower-limb exosuits with patients suffering from mobility impairments are positive in the correction of gait pattern and reducing metabolic energy consumption during hemiparetic walking. Conclusions: Lower-limb exosuits for clinical applications are still facing technological challenges. Fields of application are limited to stroke, osteoarthritis and trauma. While clinical outcomes are overall positive, improvements in the study protocols are suggested. Peer Reviewed Objectius de Desenvolupament Sostenible::3 - Salut i Benestar

Background. Ground reaction forces are the gold standard for detecting gait events, but they are not always applicable in cerebral palsy. Gait event detection using kinematic data in children with bilateral spastic cerebral palsy is an event detection method based on the sagittal plane velocity of heel and toe markers. We aimed to evaluate whether Ghoussayni's algorithm, using two different thresholds, was a valid event detection method in children with bilateral spastic cerebral palsy. We also aimed to define a new adaptation of Ghoussayni's algorithm for detecting foot strike in cerebral palsy, and study the effect of event detection methods on spatiotemporal parameters. Methods. Synchronized kinematic and kinetic data were collected retrospectively from 16 children with bilateral spastic cerebral palsy (7 males and 9 females; age 8.9 ± 2.7 years) walking barefoot at self-selected speed. Gait events were detected using methods: 1) ground reaction forces, 2) Ghoussayni's algorithm with a threshold of 0.5 m/s, and 3) Ghoussayni's algorithm with a walking speed dependent threshold. The new adaptation distinguished how foot strikes were performed (heel and/or toe) comparing the timing when the foot markers velocities fell below the threshold. Differences between the three methods, and between spatiotemporal parameters calculated from the two Ghoussayni's thresholds were analyzed. Findings. There were statistically significant (P < 0.05) differences between methods 1 and 3, and between some spatiotemporal parameters calculated from methods 2 and 3. Ghoussayni's algorithm showed better performance for foot strike than for toe off. Interpretation. Ghoussayni's algorithm using 0.5 m/s is valid in children with bilateral spastic cerebral palsy. Event detection methods affect spatiotemporal parameters.

Each year, 50% of runners suffer from injuries. Consequently, more studies are being published about running biomechanics, these studies identify factors that can help prevent injuries. Scientific evidence suggests that recreational runners should use personalized biomechanical training plans, not only to improve their performance, but also to prevent injuries caused by the inability of amateur athletes to tolerate increased loads, and/or because of poor form. This study provides an overview of the different normative patterns of lower limb muscle activation and articular ranges of the pelvis during running, at self-selected speeds, in men and women. Methods: 38 healthy runners aged 18 to 49 years were included in this work. We examined eight muscles by applying two wearable superficial electromyography sensors and an inertial sensor for three-dimensional (3D) pelvis kinematics. Results: the largest differences were obtained for gluteus maximus activation in the first double float phase (p = 0.013) and second stance phase (p = 0.003), as well as in the gluteus medius in the second stance phase (p = 0.028). In both cases, the activation distribution was more homogeneous in men and presented significantly lower values than those obtained for women. In addition, there was a significantly higher percentage of total vastus medialis activation in women throughout the running cycle with the median (25th&ndash, 75th percentile) for women being 12.50% (9.25&ndash, 14) and 10% (9&ndash, 12) for men. Women also had a greater range of pelvis rotation during running at self-selected speeds (p = 0.011). Conclusions: understanding the differences between men and women, in terms of muscle activation and pelvic kinematic values, could be especially useful to allow health professionals detect athletes who may be at risk of injury.

Estimation of neuromuscular intention using electromyography (EMG) and pattern recognition is still an open problem. One of the reasons is that the pattern-recognition approach is greatly influenced by temporal changes in electromyograms caused by the variations in the conductivity of the skin and/or electrodes, or physiological changes such as muscle fatigue. This paper proposes novel features for task identification extracted from the high-density electromyographic signal (HD-EMG) by applying the mean shift channel selection algorithm evaluated using a simple and fast classifier-linear discriminant analysis. HD-EMG was recorded from eight subjects during four upper-limb isometric motor tasks (flexion/extension, supination/pronation of the forearm) at three different levels of effort. Task and effort level identification showed very high classification rates in all cases. This new feature performed remarkably well particularly in the identification at very low effort levels. This could be a step towards the natural control in everyday applications where a subject could use low levels of effort to achieve motor tasks. Furthermore, it ensures reliable identification even in the presence of myoelectric fatigue and showed robustness to temporal changes in EMG, which could make it suitable in long-term applications.

Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/1424-8220/20/21/6388/htm Este artículo pertenece la número especial "Wearable Sensors & Gait". Background: The running segment of a triathlon produces 70% of the lower limb injuries. Previous research has shown a clear association between kinematic patterns and specific injuries during running. Methods: After completing a seven-month gait retraining program, a questionnaire was used to assess 19 triathletes for the incidence of injuries. They were also biomechanically analyzed at the beginning and end of the program while running at a speed of 90% of their maximum aerobic speed (MAS) using surface sensor dynamic electromyography and kinematic analysis. We used classification tree (random forest) techniques from the field of artificial intelligence to identify linear and non-linear relationships between di erent biomechanical patterns and injuries to identify which styles best prevent injuries. Results: Fewer injuries occurred after completing the program, with athletes showing less pelvic fall and greater activation in gluteus medius during the first phase of the float phase, with increased trunk extension, knee flexion, and decreased ankle dorsiflexion during the initial contact with the ground. Conclusions: The triathletes who had su ered the most injuries ran with increased pelvic drop and less activation in gluteus medius during the first phase of the float phase. Contralateral pelvic drop seems to be an important variable in the incidence of injuries in young triathletes.

Elastic actuators can provide safe human-robot interaction and energy efficient mobility. For this purpose they are ideal for wearable robotic applications. However, such actuators are subject to stiffness faults. We present a stiffness-fault-tolerant control strategy for complex elastic actuators, capable of adapting to changes in output stiffness, and demonstrate it on a smart variable stiffness actuator based on the MACCEPA concept. We develop the dynamics of the actuator and a model-based impedance control scheme. Biomechanical data extracted from the flexion/extension of a real knee joint are used as trajectory reference for the evaluation of the control concept in simulation. Results show that the controlled actuator is capable of tracking a reference trajectory under fault conditions and interaction disturbance while maintaining physical human-robot characteristics.

Los andamios son unas estructuraspersonalizadas, cuyo diseño influye en elcrecimiento celular para la reparación del tejido. Sin embargo, aún se encuentran en constante estudio para lograr todos los requerimientos biológicos. En este trabajo se propone una metodología y se evalúanuméricamente, utilizando el método de los elementos finitos, el comportamiento devarios diseños de andamio, Se evalúan diferentes geometrías variando el material (Titanio-Aluminio-Vanadio (Ti6Al4V) y ácido L poliláctico (PLLA) y tamaño del poro. Posteriormente, después de seleccionar los diseños más acordes con la rigidez de la estructura ósea donde se implantarán, se evaluó la viabilidad delos andamios en un ensamble andamio-hueso-placa endos etapasde sanación. La inicial, cuando no hay hueso dentro del andamio, y la final de reparación, cuando el andamio está lleno de material óseo. Para su evaluación, se propuso una geometría de andamio equivalente utilizando técnicas básicas de homogenización. Se observóque el hueso dentro del andamio de Ti6Al4V, aumenta significativamente las propiedades mecánicas de la zona, pudiendo generarse importantes zonas de concentración de esfuerzo. Esto pone en evidencia la conveniencia de que el andamio sea biodegradable para evitar lesiones posteriores al paciente, debido a la diferencia de rigidez a lo largo del fémur.En esta evaluación se tomaron en cuenta solamente dos materiales biocompatibles como lo son elTi6Al4V yelácido L poliláctico (PLLA)(biodegradable).La selección de estos obedeció a la amplia información que existe en la literatura sobre esta afirmación más que a un estudio riguroso de las propiedades de estos.

Introduction: Ozone is a potent antioxidant that acts as a precursor of various radicals, being indicated as a powerful therapy, assisting in the process of tissue healing. Objectives: The proposal of this study was to analyze material and structural properties via mechanical testing in tibias after application of ozone in bone defects produced surgically. Methods: Ten male 40-day old albino Wistar rats have been used, divided in two groups: control group and ozone group, this last one being treated with ozonized water in 25 µg/mL of concentration until the day of euthanasia. Trichotomy and longitudinal incision was conducted in the animals’ leg skin, exposing the tibia’s diaphysis of both antimers, and with help of a high rotation pen a flaw has been produced on the bone. After 60 days of surgery the animals were euthanized, and tibias were collected for biomechanical analysis. Results: The results of the biomechanical properties – structural and material – evidenced significant interactions through exposure to ozone, showing a diminished bone resistance in animals from the control group, observed by the decrease of the maximum force (N) needed to rupture the bone when compared to the value needed to break the bones of the animals from the ozone group, and the analysis of the morphometrical properties did not show any difference between both experimental groups. Conclusion: The use of ozone did not alter the morphological structures of the tibias, and the group which used ozone presented more resistance during mechanical testings, because the maximum force for the rupture of tibia was greater in this group. Introducción: El ozono es un potente oxidante que actúa como precursor de varios radicales, siendo indicado con potente terapéutico con auxiliar en el proceso de reparación de tejidos. Objetivos: El propósito de este estudio fue analizar las propiedades materiales y estructurales mediante ensayos mecánicos en tibias después de la aplicación del ozono en la insuficiencia ósea producida quirúrgicamente. Metodología: Se utilizaron diez ratas wistar albinas macho con 40 días de vida, divididas en dos grupos: grupo de control y grupo de ozono, que fue tratado con agua ozonizada a una concentración de 25 g/ml hasta la fecha de la eutanasia. En la pierna de los animales, se realizó tricotomía e incisión longitudinal en la piel, exponiendo la diáfisis de la tibia de ambos antimémeros y con la ayuda de una pluma de alta rotación, produciendo una falla ósea. Después de 60 días de cirugía, los animales fueron eutanasiados, y las tibias fueron recolectadas para análisis biomecánicos. Resultados: las propiedades biomecánicas (estructurales y materiales) mostraron interacciones significativas a través de la exposición al ozono, evidenciando una disminución en la resistencia ósea de los animales del grupo de control, observadas por la disminución de la fuerza máxima (N) necesaria para romper el hueso en comparación con los valores necesarios para romper los huesos de los animales del grupo de ozono y los análisis de propiedades morfométricas no revelaron diferencias entre los grupos experimentales. Conclusión: El uso del ozono no alteró las propiedades morfológicas de las tibias y que el grupo que utilizó ozono exhibiera más resistencia en el ensayo mecánico, porque la fuerza máxima para la ruptura tibial fue mayor en este grupo. Introdução: O ozônio é um oxidante potente que age como precursor diversos radicais, sendo indicado com terapêutico potente com auxiliar no processo de reparação tecidual. Objetivos: A proposta do presente estudo foi analisar as propriedades materiais e estruturais por meio de ensaio mecânico em tíbias após aplicação de ozônio em falha óssea produzidas cirurgicamente. Metodologia: Foram utilizados 10 ratos albinos Wistar, machos, com 40 dias de vida, divididos em dois grupos: grupo controle e grupo ozônio, sendo este tratado com água ozonizada na concentração de 25 μg/ml até a data da eutanásia. Na perna dos animais foi realizada tricotomia e incisão longitudinal na pele, expondo a da diáfise da tíbia de ambos antimeros e com auxílio de uma caneta de alta-rotação, produzindo uma falha óssea. Após 60 dias da cirurgia os animais foram eutanesiados, as tibias foram coletadas para análise biomecânica. Resultados: as propriedades biomecânicas (estruturais e materiais) evidenciaram interações significativas mediante a exposição ao ozônio, evidenciando uma diminuição na resistência óssea dos animais do grupo controle, observado por meio da diminuição na força máxima (N) necessária para romper o osso quando comparado aos valores necessários para quebrar os ossos dos animais do grupo ozônio e as análises das propriedades morfométricas não revelaram diferenças entre os grupos experimentais. Conclusão: O uso do ozônio não alterou as propriedades morfológicas das tíbias e que o grupo que usou ozônio exibiu mais resistência no ensaio mecânico, pois a força máxima para ruptura da tíbia foi maior neste grupo.

Understanding the atomistic origin of defects in two-dimensional transition metal dichalcogenides, their impact on the electronic properties, and how to control them is critical for future electronics and optoelectronics. Here, we demonstrate the integration of thermochemical scanning probe lithography (tc-SPL) with a flow-through reactive gas cell to achieve nanoscale control of defects in monolayer MoS2. The tc-SPL produced defects can present either p- or n-type doping on demand, depending on the used gasses, allowing the realization of field effect transistors, and p-n junctions with precise sub-μm spatial control, and a rectification ratio of over 104. Doping and defects formation are elucidated by means of X-Ray photoelectron spectroscopy, scanning transmission electron microscopy, and density functional theory. We find that p-type doping in HCl/H2O atmosphere is related to the rearrangement of sulfur atoms, and the formation of protruding covalent S-S bonds on the surface. Alternatively, local heating MoS2 in N2 produces n-character.

Additive manufacturing (AM) processes have undergone significant progress in recent years, having been implemented in sectors as diverse as automotive, aerospace, electrical component manufacturing, etc. In the medical sector, different devices are printed, such as implants, surgical guides, scaffolds, tissue engineering, etc. Although nowadays some implants are made of plastics or ceramics, metals have been traditionally employed in their manufacture. However, metallic implants obtained by traditional methods such as machining have the drawbacks that they are manufactured in standard sizes, and that it is difficult to obtain porous structures that favor fixation of the prostheses by means of osseointegration. The present paper presents an overview of the use of AM technologies to manufacture metallic implants. First, the different technologies used for metals are presented, focusing on the main advantages and drawbacks of each one of them. Considered technologies are binder jetting (BJ), selective laser melting (SLM), electron beam melting (EBM), direct energy deposition (DED), and material extrusion by fused filament fabrication (FFF) with metal filled polymers. Then, different metals used in the medical sector are listed, and their properties are summarized, with the focus on Ti and CoCr alloys. They are divided into two groups, namely ferrous and non-ferrous alloys. Finally, the state-of-art about the manufacture of metallic implants with AM technologies is summarized. The present paper will help to explain the latest progress in the application of AM processes to the manufacture of implants.

Walking rehabilitation using exoskeletons is of high importance to maximize independence and improve the general well-being of spinal cord injured subjects. We present the design and control of a lightweight and modular robotic exoskeleton to assist walking in spinal cord injured subjects who can control hip flexion, but lack control of knee and ankle muscles. The developed prototype consists of two robotic orthoses, which are powered by a motor-harmonic drive actuation system that controls knee flexion–extension. This actuation module is assembled on standard passive orthoses. Regarding the control, the stance-to-swing transition is detected using two inertial measurement units mounted on the tibial supports, and then the corresponding motor performs a predefined flexion–extension cycle that is personalized to the specific patient’s motor function. The system is portable by means of a backpack that contains an embedded computer board, the motor drivers, and the battery. A preliminary biomechanical evaluation of the gait-assistive device used by a female patient with incomplete spinal cord injury at T11 is presented. Results show an increase of gait speed (+24.11%), stride length (+7.41%), and cadence (+15.56%) when wearing the robotic orthoses compared with the case with passive orthoses. Conversely, a decrease of lateral displacement of the center of mass (−19.31%) and step width (−13.37% right step, −8.81% left step) are also observed, indicating gain of balance. The biomechanical assessment also reports an overall increase of gait symmetry when wearing the developed assistive device.

To evaluate the morphological changes on the intervertebral foramen and segmental lordosis related to the transforaminal lumbar interbody fusion (TLIF) positioning.PEEK cages were placed in the disc space (L1-S1) of a polyurethane anatomical model. Cages of different heights (8 mm, 10 mm, 12 mm and 14 mm) were positioned in the posterior, medial or anterior part of the vertebral body surface, and the intervertebral foramen and segmental lordosis heights were measured after their insertion.The vertebral foramen height decreased in all positions and heights of the cages in relation to the control. The cage posterior positioning induced a smaller reduction in the vertebral foramen height. Vertebral lordosis tended to increase in relation to the control, and the greatest increase occurred with the cage posterior positioning.Cage positioning induces changes in the intervertebral foramen height and in the vertebral segment lordosis. Cage posterior positioning induces a smaller reduction of the intervertebral foramen height and increases the vertebral segment lordosis.Avaliar as alterações morfológicas do forâmen intervertebral e da lordose segmentar relacionadas ao posicionamento do espaçador intersomático na artrodese lombar intersomática transforaminal (TLIF).Cages de PEEK foram colocados no espaço discal (L1-S1) de modelo antômico de poliuretana. Os cages de diferentes alturas (8 mm, 10 mm, 12 mm e 14 mm) foram posicionados na parte posterior, média ou anterior da superfície do corpo vertebral e a altura do forame intervertebral e lordose segmentar mensuradas após a sua inserção.Foi observado redução da altura do forame vertebral em todos os posicionamentos e alturas dos cages em relação ao controle. O posicionamento posterior do Cage induziu à menor redução da altura do forame vertebral. A lordose do semento vertebral apresentou tendência de aumento em relação ao controle, tendo sido observado a maior tendência com o posicionamento posterior do Cage.O posicionamento do Cage induz a alterações da altura do forame intervertebral e lordose do segmento vertebral. O posicionamento posterior do Cage induz a menor redução da altura do forame intervertebral e aumento da lordose do segmento vertebral.

Introduction: Different mechanical behaviors in resistance training can result in certain changes in the cardiovascular system. Objective: To verify the acute behavior of the main cardiovascular variables (heart rate, blood pressure, and double product) when performing resistance training with mono and multiarticular exercises. Methods: 10 male subjects participated in the study (26 ± 4 years; 81 ± 6 kg; 1.77 ± 2 m; 23 ± 1 kg / m2). They performed a test and retest for 8RM in the bench press and crucifix exercises on the machine. After the loads were outlined, they performed the intervention with the exercises, initially with a monoarticular activation containing two sets of 12 repetitions with 50% of the load acquired in the 8RM test of each exercise, using an interval of 60 seconds between one set and another. Additionally, three sets of 8 repetitions (80% 8RM) were performed with an interval between sets of 120 seconds. The execution speed was determined at a moderate level (2s for concentric, 2s for eccentric). It was measured before and during (series 1, series two, and series 3. Named as moments) heart rate exercises using POLAR, model RS800CX Multisport® and blood pressure using OMRON M6 (HEM-7001- E) ®. Then, the double product was calculated using the formula [HR (bpm) X SBP (mmHg)]. Results: In the heart rate analysis, there was an intra-condition difference for moments 1, 2, and 3 compared to rest (p 0.999). In systolic blood pressure, intra-conditions, differences were observed for moments 1, 2, and 3 compared to rest (p 0.999), moment 1 (p = 0.714), 2 (p = 0.999) and 3 (p> 0.999). For diastolic blood pressure, intra conditions, for bench press no significant differences were found for moments 1 (p = 0.331), 2 (p = 0.505) and 3 (p = 0.505) when compared to rest. In the same way it was for the crucifix, wherein the comparison with rest, no difference was observed in moments 1 (p = 0.849), 2 (p = 0.195) and 3 (p = 0.105). In the same sense, no difference was also observed in the comparisons between conditions for rest (p> 0.999), moment 1 (p = 0.999), 2 (p = 0.989) and 3 (p = 0.948). Finally, the double product in intra-condition comparisons found differences between moments 1, 2, and 3 compared to rest (p 0.999). Conclusion: It is suggested that resistance training composed of mono and multi-joint exercises offers differences in hemodynamic responses but without differences between the types of mechanics applied by the exercises. Therefore, these results offer a partiality of what can happen with heart rate, blood pressure, and double product. Introducción Diferentes comportamientos mecánicos en el entrenamiento de resistencia pueden resultar en ciertos cambios en el sistema cardiovascular. Objetivo: Verificar el comportamiento agudo de las principales variables cardiovasculares (frecuencia cardíaca, presión arterial y doble producto) en el entrenamiento de resistencia con ejercicios uni y multiarticulares. Métodos: participaron 10 individuos del sexo masculino (26 ± 4 años; 81 ± 6 kg; 1,77 ± 2 m; 23 ± 1 kg / m2). Realizaron una prueba y una nueva prueba de 8RM en los ejercicios de press de banca y crucifijo en la máquina. Tras delimitar las cargas, realizaron la intervención con los ejercicios, inicialmente con una activación mioarticular conteniendo 2 series de 12 repeticiones con el 50% de la carga adquirida en el test 8RM de cada ejercicio, utilizando un intervalo de 60 segundos entre una serie y otra. . Además, se realizaron 3 series de 8 repeticiones (80% 8RM) con un intervalo entre series de 120 segundos. La velocidad de ejecución se determinó a un nivel moderado (2 s para concéntrico, 2 s para excéntrico). La frecuencia cardíaca con el modelo POLAR RS800CX Multisport® y la presión arterial con el OMRON M6 (HEM-7001-E) ® se midieron antes y durante (serie 1, serie 2 y serie 3. Nombrados como momentos). A continuación, se calculó el producto doble usando la fórmula [HR (lpm) X PAS (mmHg)]. Resultados: En el análisis de la frecuencia cardíaca, hubo una diferencia dentro de las condiciones para los momentos 1, 2 y 3 en comparación con el reposo (p 0,999). En la presión arterial sistólica, intracondiciones, se observaron diferencias para los momentos 1, 2 y 3 cuando se comparó con el reposo (p 0,999), momento 1 (p = 0,714), 2 (p = 0,999) y 3 (p> 0,999). Para la presión arterial diastólica, intracondiciones, para press de banca, no se encontraron diferencias significativas para los momentos 1 (p = 0.331), 2 (p = 0.505) y 3 (p = 0.505) al compararlos con el reposo. Lo mismo ocurrió con el crucifijo, donde en comparación con el reposo, no se observó diferencia en los momentos 1 (p = 0,849), 2 (p = 0,195) y 3 (p = 0,105). Del mismo modo, no se observó diferencia en las comparaciones entre las condiciones de reposo (p> 0,999), momento 1 (p = 0,999), 2 (p = 0,989) y 3 (p = 0,948). Finalmente, el producto doble en las comparaciones intra-condición se encontraron diferencias para los momentos 1, 2 y 3 en comparación con el reposo (p 0,999). Conclusión: Se sugiere que el entrenamiento de resistencia consistente en ejercicios uni y multiarticulares ofrece diferencias en las respuestas hemodinámicas, pero sin diferencias entre los tipos de mecánicas aplicadas por los ejercicios. Por lo tanto, estos resultados ofrecen una parcialidad de lo que puede suceder con la frecuencia cardíaca, la presión arterial y el doble producto. Introdução Diferentes comportamentos mecânicos no treinamento resistido pode resultar em determinadas alterações no sistema cardiovascular. Objetivo: Verificar o comportamento agudo das principais variáveis cardiovasculares (Frequência cardíaca, pressão arterial e duplo produto) na realização de treinamento resistido com exercícios mono e multiarticulares. Metodos: 10 indivíduos do sexo masculino participaram do estudo (26±4 years; 81±6 kg; 1,77±2 m; 23±1 kg/m2). Realizaram teste e reteste para 8RM nos exercícios supino reto e crucifixo na máquina. Após o delineamento das cargas, realizaram a intervenção com os exercícios, inicialmente com uma ativação mioarticular contento 2 séries de 12 repetições com 50% da carga adquirida no teste de 8RM de cada exercício, utilizando um intervalo de 60 segundos entre uma série e outra. Adicionalmente, foram realizadas 3 séries de 8 repetições (80% 8RM) com intervalo entre séries de 120 segundos. A velocidade de execução foi determinada em nível moderado (2s para concêntrica, 2s para excêntrica). Foi medida antes e durante (série 1, série 2 e série 3. Nomeadas como momentos) os exercícios a frequência cardíaca utilizando POLAR, modelo RS800CX Multisport® e a pressão arterial usando o OMRON M6 (HEM-7001- E) ®. Adiante, foi calculado o duplo produto através da fórmula [HR (bpm) X SBP (mmHg)]. Resultados: Na análise da frequência cardíaca, houve diferença intra condições para os momentos 1, 2 e 3 quando comparado com repouso (p0.999). Na pressão arterial sistólica, intra condições, foi observado diferenças para os momentos 1, 2 e 3 quando comparados com repouso (p0.999), momento 1 (p=0.714), 2 (p=0.999) e 3 (p>0.999). Para pressão arterial diastólica, intra condições, para supino reto não foram encontradas diferenças significativas para os momentos 1 (p=0.331), 2 (p=0.505) e 3 (p=0.505) quando comparado com repouso. Da mesma forma foi para o crucifixo, onde na comparação com repouso, nenhuma diferença foi observada nos momentos 1 (p=0.849), 2 (p=0.195) e 3 (p=0.105). No mesmo sentido, nenhuma diferença também não foi observada nas comparações inter condições para repouso (p>0.999), momento 1 (p=0.999), 2 (p=0.989) e 3 (p=0.948). Por fim, o duplo produto nas comparações intra condições foram encontradas diferenças para os momentos 1, 2 e 3 quando comparados com o repouso (p0.999). Conclusão: Sugere-se que o treinamento resistido composto por exercícios uni e multi articular oferecem diferenças nas respostas hemodinâmicas, porém sem diferenças entres os tipos de mecânicas aplicadas pelos exercícios. Portanto, estes resultados oferecem uma parcialidade do que pode acontecer com a frequência cardíaca, pressão arterial e duplo produto.

The purpose of this work is to develop an experimental physical model of the shoulder joint complex. The aim of this research is to validate the model built and identify the forces on specified positions of this joint. The shoulder musculoskeletal structures have been replicated to evaluate the forces to which muscle fibres are subjected in different equilibrium positions: 60º flexion, 60º abduction and 30º abduction and flexion. The physical model represents, quite accurately, the shoulder complex. It has 12 real degrees of freedom, which allows motions such as abduction, flexion, adduction and extension and to calculate the resultant forces of the represented muscles. The built physical model is versatile and easily manipulated and represents, above all, a model for teaching applications on anatomy and shoulder joint complex biomechanics. Moreover, it is a valid research tool on muscle actions related to abduction, adduction, flexion, extension, internal and external rotation motions or combination among them. Este trabajo consiste en desarrollar un modelo físico experimental del complejo articular del hombro. El objetivo en esta investigación es validar el modelo construido e identificar las fuerzas en posiciones específicas de esta articulación. Se han reproducido las estructuras musculo-esqueléticas del hombro para evaluar las fuerzas a las que están sometidas las fibras musculares en diferentes posiciones de equilibrio: flexión 60º, abducción 60º y aducción más flexión 30º. El modelo físico representa con suficiente aproximación a la realidad el complejo del hombro; posee 12 grados reales de libertad, lo cual permite realizar movimientos como abducción, flexión, aducción y extensión y calcular las fuerzas resultantes de los músculos representados. El modelo físico construido es versátil y fácilmente manipulable y constituye, por encima de todo, un modelo para aplicaciones didácticas en anatomía y biomecánica del complejo articular del hombro. Así mismo, es una herramienta de investigación válida sobre las acciones musculares asociadas a los movimientos de abducción, aducción, flexión, extensión, rotación interna y externa o combinaciones de los mismos.

espanolIntroduccion: La obesidad y la osteoporosis (OP) son dos patologias muy prevalentes en nuestra sociedad actual. El efecto de la obesidad sobre la calidad osea se encuentra en debate en la actualidad. Objetivo: Valorar el efecto del peso corporal sobre la microestructura y las propiedades biomecanicas de hueso trabecular procedente de biopsias de extremidad proximal de femur de pacientes con fractura de cadera por fragilidad. Material y metodo: Estudio transversal de 16 pacientes con fractura de cadera. 2 grupos segun su IMC: (A) sujetos normopeso y (B) con obesidad. Recogimos biopsias de hueso trabecular de cabeza femoral. Valoramos determinaciones bioquimicas (PTH, 25(OH) vitamina D e IGF-1), marcadores de remodelado oseo (PINP,CTX), masa osea (DMO cuello y cadera total), microestructura osea y estudio biomecanico (µCt). El analisis estadistico: t-Student (SPSS 22.0) significacion p Conclusion: La obesidad puede ser un factor protector de la calidad osea en la region femoral y tiene menos efecto sobre la densidad mineral osea. EnglishIntroduction: Obesity and osteoporosis (OP) are two very prevalent diseases in our society today. The effect of obesity on bone quality is currently a subject under discussion. Objective: To assess the effect of body weight on the microstructure and biomechanical properties of trabecular bone biopsies from the proximal end of the femur in patients with hip fracture fragility. Material and methods: Cross-sectional study of 16 patients with hip fracture. The 2 groups are divided according to their BMI: (A) normal weight individuals and (B) those with obesity. We collected biopsies of cancellous bone from the femoral head and assessed biochemical determinations (PTH, 25 (OH) vitamin D and IGF-1), bone remodeling markers (PINP, CTX), bone mass (BMD neck and total hip), bone microstructure and biomechanical study (µCt). Statistical analysis: Student's t test (SPSS 22.0) significance p

Although gait problems have been reported in patients with lower limb lymphedema (LLL), the gait pattern (GP) changes have not been documented yet. However, it is possible that patients with LLL show abnormal GP that can be related to biomechanical complications related to osteoarthritis or falls affecting the quality of life. Ground reaction force analysis during gait allows objective assessment of the patients and it can be used to plan a rehabilitation approach. Objective: To analyze the GRF during gait in patients LLL. Methods: An experimental descriptive study was realized with twenty-three LLL patients, both unilateral and bilateral and classified as moderate and severe, participated in the experiments. The patients walked on a force plate while the three ground reaction force (GRF) components, vertical, mediolateral (M-L) and anteroposterior (A-P), under their feet were recorded and analyzed. Results: In the patients with unilateral lymphedema, either moderate or severe, the vertical GRF components of the affected limb were similar to the sound one and also resembling those found in healthy adults. The M-L GRF was smaller in the non-affected side. In patients with bilateral lymphedema gait speed was significantly slower. More interestingly, the vertical GRF pattern was flat, not showing the typical 2-peak shape. Finally, the large M-L forces found suggest gait stability problems. Conclusions: The patients showed abnormal GRF patterns, including compensation with the non-affected leg. The GRF variability was higher in the patients with severe unilateral lymphedema. Bilateral lymphedema results in lower A-P forces. Stance phase duration was longer in patients with bilateral and severe lymphedema

The objective of this paper is to simulate the human hand when grasping an object, considering the angles of the finger joints and the fingertip deformation. To study the grasp of an object used in activities of daily life (ADL) we focus on the equations given by grasps with force-closure. In this paper we address several topics and study grasping holistically, including power and precision grasping, the position of the finger and joint angles, fingertip deformation and fingertip forces (normal and frictional forces), and assess ho wall these features combine to perform a complete grasping action. Conclusions: We describe the strategy used to solve the problem of calculating the force when grasping with five fingers; the same strategy is used in both power and precision grasps.

Background: Hallux abductus valgus (HAV) is a forefoot condition produced by extrinsic and intrinsic factors. Shoes with a high heel height and a typical narrow tip toe box can induce deviations in both the proximal phalanx of the hallux (PPH) and the first metatarsal (IMTT) bones. Nevertheless, the isolated role of heel height remains unclear in the development of HAV pathology. Objectives: The goal was to determine if the heel height increase of shoes without a narrow box toe could augment the PPH and IMTT deviation in frontal, sagittal, and transverse planes toward the first metatarsophalangeal joint (MPJ) and the first metatarsocuneiform joint (MCJ), respectively, during static and dynamic conditions in relation to precursor movements of HAV. Methods: Women with an average age of 25.10 &plusmn, 4.67 years were recruited in this cross-sectional study to assess the three planes of motion of PPH and IMTT while wearing high heels with heights at 3, 6, 9 cm and unshod conditions via sandals. The measurements used an electromagnetic goniometer device with sensors placed on medial aspects of the PPH and IMTT bones under static and dynamic conditions. Results: Wearing shoes with a 6 cm heel in dynamic condition may increase the PPH valgus and abduction deviation from 3.15 &plusmn, 0.10&deg, to 3.46 &plusmn, 0.05&deg, (p &lt, 0.05) and from 1.35 &plusmn, 0.28&deg, to 1.69 &plusmn, 0.30&deg, 0.001), respectively. In addition, a PPH abduction increase from 1.01 &plusmn, 0.36&deg, to 1.31 &plusmn, 0.46&deg, 0.05) after wearing shoes with a 6 cm heel height was observed under static conditions. Conclusions: Wearing shoes with a heel height of 6 cm without a narrow box toe interference may produce PPH abduction and valgus deviations related to HAV formation.

In biomaterials science, it is nowadays well accepted that improving the biointegration of dental and orthopedic implants with surrounding tissues is a major goal. However, implant surfaces that support osteointegration may also favor colonization of bacterial cells. Infection of biomaterials and subsequent biofilm formation can have devastating effects and reduce patient quality of life, representing an emerging concern in healthcare. Conversely, efforts toward inhibiting bacterial colonization may impair biomaterial–tissue integration. Therefore, to improve the long-term success of medical implants, biomaterial surfaces should ideally discourage the attachment of bacteria without affecting eukaryotic cell functions. However, most current strategies seldom investigate a combined goal. This work reviews recent strategies of surface modification to simultaneously address implant biointegration while mitigating bacterial infections. To this end, two emerging solutions are considered, multifunctional chemical coatings and nanotopographical features.

The Lumbo-Sacral Spine is a structure of the spine that supports one of the greatest burdens of the human body. It constitutes a biomechanical unit and is formed by 5 lumbar vertebrae distributed in such a way that each supports a weight. The Lumbo-Sacral Spine distributes a load and acts as a shock absorber for the spine thanks to its flexibility. The knowledge of the morphology of this spinal structure and its articulation with the first sacral vertebra is fundamental to determine the biomechanical behavior of the entire spinal column. Furthermore, it allows the study of its type of support, its stability and degree of cushioning, its mobility and, in short, all its cinematic and dynamic characteristics. The present work presents a morphological study of the lumbar spine and the lumbosacral articulation of 108 non-pathological adult individuals and without regular and demanding physical or sportive physical activity. The sample consists of simple x-rays of the sagittal plane. The objective proposed in the present work is to obtain a normal lumbosacral column model of a significant population studied as a control group. Obtaining the proposed model allows knowledge and characterization of the distribution of the non-pathological population and its deviations from the most frequent values. The typing of the lumbar morphology of a control group makes it possible to have a decision tool at the population level to establish a preventive or healthy policy based on the analysis of the risks and priority criteria for action. The incidence of this model in the prevention of pathologies of the lumbar spine has a direct incidence with the labor, personal and social cost that this type of pathologies supposes. Sin financiación No data WoS Scopus (Conference Paper) No data SPI – ICEE (2018) UEM

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior It has been suggested that the foot acts as a twisted osteoligamentous plate to control pronation and facilitate supination during walking. The aim of this study was to investigate the effect of an orthosis inspired by the concept of a foot’s twisted osteoligamentous plate on the kinematics of foot-ankle complex. Thirty-five subjects underwent a kinematic assessment of the foot-ankle complex during walking using three different orthoses: (1) Twisted Plate Spring (TPS) orthosis: inspired by the concept of a twisted osteoligamentous plate shape and made with a spring-like material (carbon fiber); (2) Flat orthosis: control orthosis made of a non-elastic material with a non-inclined surface; and (3) Rigid orthosis: control orthosis made of a non-elastic material, with the same shape of the TPS. Repeated measures analyses of variance demonstrated that the TPS reduced the duration and magnitude of rearfoot eversion (p ≤ 0.03), increased rearfoot inversion relative to shank (p

Stroke is one of the leading causes of upper extremity disability around the world. Whenever a stroke happens stroke survivor’s brain commands cannot reach some muscles of upper extremities although those muscles could contract. Therefore, shoulder, elbow or wrist joint cannot perform expected motion, and this will hamper their activities of daily living (ADLs). The objective of rehabilitation is to externally drive the upper extremity move to improve muscle movements. The current state of upper extremity rehabilitation may improve by using a model-based computer simulation of arm movement for personalizing robotic devices and interventions. This study attempts to review technologies used in upper extremity rehabilitation on two aspects: computer models and robotic devices. A summary of existing virtual upper extremity models is provided. As well, different robotic devices that are developed for upper limb rehabilitation is also discussed here.

An objective analysis of the human movement can help both clinical assessment and sports performance. Kinovea is a free 2D motion analysis software that can be used to measure kinematic parameters. This low-cost technology has been used in sports sciences, as well as in the clinical and research fields. One interesting tool is that it can measure an object (or person) passing in front of the camera, taking into account the perspective between the camera and the recorded object. Although it has been validated as a tool to assess time-related variables, few studies assessed its validity compared to a Gold Standard; furthermore, its reliability in different perspectives has not been previously assessed. The main objective of this study is to determine the validity of the Kinovea software compared to AutoCAD, and its intra and inter-rater reliability in obtaining coordinates data; a second objective is to compare their results at 4 different perspectives (90°, 75°, 60° and 45°) and to assess the inter and intra rater reliability at each perspective. For this purpose, a wire structure figure in the shape of a human lower limb was designed and measured in AutoCAD; it was then recorded during a pendular motion with a video-camera placed at distance of 5 m and analyzed with Kinovea in the 4 perspectives (90°, 75°, 60° and 45°). Each frame was examined by three observers who made two attempts. A multiple approach was applied involving the analysis of the systematic error, with a two-way ANOVA 2x4; the relative reliability with Intraclass Correlation Coefficient (ICC) and the Coefficient of Variance (CV) (95% confidence interval); and the absolute reliability with the Standard Error (SE). The results indicate that the Kinovea software is a valid and reliable tool that is able to measure accurately at distances up to 5 m from the object and at an angle range of 90°–45°. Nevertheless, for optimum results an angle of 90° is suggested.

Resumen Quesada Salazar, N. (2021). Alteraciones musculoesqueléticas y adaptaciones biomecánicas durante los trimestres de embarazo: una revisión sistemática. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-27. El embarazo es un proceso progresivo que involucra cambios de tipo hormonal, mecánico, fisiológico y emocional en la mujer y que causa que el sistema musculoesquelético se adapte constantemente. Estos cambios suelen identificarse a través de la postura y la biomecánica de los movimientos en la vida diaria. En esta investigación, se realizó una revisión sistemática para encontrar las principales alteraciones y adaptaciones durante el embarazo, incluyendo artículos del 2008 al 2018, con mujeres gestantes sanas, con un solo feto, sin alteraciones musculoesqueléticas previas, de Índice de Masa Corporal (IMC) normal y cualquier metodología de investigación excepto estudios de caso. Se identificaron 13 estudios que refieren evaluar las tres etapas de gestación, edades desde los 20 a los 35 años, así como con diversos objetivos de investigación. La postura de la mujer gestante presenta un aumento de la lordosis lumbar, la curvatura torácica y el ángulo de inclinación anterior de la pelvis. La tarea de sentarse y levantarse de una silla requiere de mayor control del movimiento, así como de tiempo de ejecución. La oscilación y las fuerzas de reacción del suelo del Centro de Presión corporal aumentan al estar de pie, lo que resulta en una mayor distancia entre los pies, como estrategia de control del equilibrio. Finalmente, la biomecánica de la marcha se adapta a una menor velocidad, longitud de paso y etapa de despegue de los pies del piso, con un aumento del ancho de paso y una mayor base de apoyo. En la gestación, la mujer desarrolla adaptaciones de tipo anatómicas y mecánicas como respuesta a los cambios progresivos experimentados. Abstract Quesada Salazar, N. (2021). Musculoskeletal changes and biomechanic adaptations during the three trimesters of pregnancy: a sistematic review. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-27. Pregnancy is a progressive process involving hormonal, mechanical, physiological, and emotional changes in women that stimulates the musculoskeletal system to adapt constantly. These changes are usually identified through posture and the biomechanics of day-to-day movements. This study consists of a systematic review of the main alterations and adaptations during pregnancy, including articles from 2008 to 2018 that involved healthy pregnant women without previous musculoskeletal affections, with a single fetus and normal BMI, and any methods of study excluding case studies. Thirteen studies were identified which indicate evaluation of participants ages from 20 to 35 years during their three trimesters of pregnancy, as well as different study objectives. Posture in a pregnant woman shows an increase in the lumbar lordosis, thoracic curvature, and anterior tilt of the pelvis. The task of sitting and rising from a chair requires more control to complete the movement as well as increased execution time. Oscillation movement and ground reaction forces of the center of pressure of the body increase during standing posture, which results in a greater distance between the feet as a strategy to control the balance. Finally, gait biomechanics adapt to a slower speed, smaller step length, and less time with feet off the ground, but a wider step and support base. During pregnancy, women develop anatomic and mechanic adaptations in response to the progressive changes they experience. Resumo Quesada Salazar, N. (2021). Alterações musculoesqueléticas e adaptações biomecânicas durante os trimestres de gravidez: uma revisão sistemática. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-27. A gravidez é um processo progressivo que envolve mudanças de tipo hormonal, mecânico, fisiológico e emocional na mulher e que faz com que o sistema musculoesquelético se adapte constantemente. Essas mudanças tendem a ser identificadas por meio da postura e a biomecânica dos movimentos na vida diária. Nesta pesquisa foi realizada uma revisão sistemática para encontrar as principais alterações e adaptações durante a gravidez, incluindo artigos de 2008 a 2018, com mulheres gestantes saudáveis, com um único feto, sem alterações musculoesqueléticas prévias, com Índice de Massa Corporal (IMC) normal e qualquer metodologia de pesquisa, exceto estudos de caso. Foram identificados 13 estudos que registram avaliar as três etapas de gestação, com idades desde os 20 aos 35 anos, igualmente com diversos objetivos de pesquisa. A postura da mulher gestante apresenta um aumento de lordose lombar, curvatura toráxica e ângulo de inclinação anterior da pelve. A tarefa de sentar-se e levantar-se de uma cadeira exige maior controle do movimento, assim como de tempo de execução. A oscilação e as forças de reação do solo do Centro de Pressão corporal aumentam ao estar de pé, resultando em uma maior distância entre os pés, como estratégia de controle do equilíbrio. Finalmente, a biomecânica da marcha se adapta a uma menor velocidade, longitude de passo e fase de retirada dos pés do chão, com um aumento da largura do passo e uma maior base de apoio. Na gestação, a mulher desenvolve adaptações de tipo anatômicas e mecânicas como resposta para mudanças progressivas experimentadas.

Introduction When stress and strain levels in the bone-implant system exceed It's capacity, a mechanical fatigue occurs, resulting in collapse and loss of osseointegration. Objective Analyze biomechanical behavior in single implant-supported prosthesis with implants of different diameters in the posterior mandible. Material and method Three different finite element models of Cone-Morse implants with the same height were created, varying the diameter (3.3 mm, 4.1 mm and 4.8 mm). The mandibular first molar area was the location of the implant, with It´s component and overlying prosthetic crown. The jawbone was composed of cortical and cancellous bone. Refined mesh of 0.5 mm was created in the critical interfaces to be analyzed. The loading of the models was performed at the point of occlusal contact with an occlusal load of 400 N. Result Maximum stress and strain occurred in the cervical regions of the implants in all groups, either in the implants or in components as well as in the analysis of cortical bone. The greater the diameter, the lower the stress and strain found in the implant. The 3.3 mm group had the highest strain in peri-implant cortical bone, and the 4.1 mm group had the smallest deformation, significantly lower than in the 4.8 mm group. Conclusion Although the biggest implant diameter (4.8 mm) appears to have lower values of stress and strain, the group of intermediate implant diameter (4.1 mm) showed less deformation rate in the cortical peri-implant bone. Therefore it is concluded that the 4.1 mm implant platform presented a more biomechanically effective peri-implant bone maintenance. Resumo Introdução Quando os níveis de tensão e compressão gerados no sistema osso-implante excederem a capacidade óssea ocorre uma fadiga mecânica, resultando em colapso e perda da osseointegração. Objetivo Analisar o comportamento biomecânico em próteses unitárias implanto-suportadas com implantes de diferentes diâmetros na região posterior de mandíbula. Material e método Foram criados três modelos de elementos finitos de implantes cone-Morse de mesmo comprimento, variando-se o diâmetro: 3,3 mm, 4,1 mm e 4,8 mm. A localização do implante foi a região de primeiro molar inferior, com componente e coroa protética sobrejacentes. A mandíbula foi composta por osso cortical e medular. Foi criada malha refinada de 0,5 mm nas interfaces criticas a serem analisadas. O carregamento dos modelos foi realizado nos pontos de contatos oclusais, com uma carga oclusal de 400 N. Resultado Tensão e deformação máximas ocorreram nas regiões cervicais dos implantes em todos os grupos, tanto na análise dos implantes e componentes quanto na análise do osso cortical. Quanto maior foi o diâmetro, menores foram tensão e deformação encontradas no implante. O grupo 3,3 mm apresentou a maior deformação em osso cortical periimplantar, tendo o grupo 4,1 mm a menor deformação, significantemente menor em relação ao grupo 4,8 mm. Conclusão Apesar de o implante de maior diâmetro (4,8 mm) ter apresentado os menores valores de tensão e deformação, o grupo do implante de diâmetro intermediário (4,1 mm) mostrou menor taxa de deformação em osso cortical periimplantar. Portanto conclui-se que o implante de plataforma 4,1 mm apresentou-se mais efetivo biomecanicamente para manutenção óssea periimplantar.

Background Altered hip, knee and foot kinematics have been systematically observed in individuals with patellofemoral pain (PFP). However, less attention has been given to the altered dynamic postural control associated with PFP. Additionally, the relative contribution of kinematic impairments to the postural behavior of subjects with PFP remains an open question that warrants investigation. The aims of this study were: i) to investigate possible differences in hip adduction, rearfoot eversion, knee flexion and displacement area of the center of pressure (COP) in individuals with PFP in comparison to controls during stair ascent; and (ii) to determine which kinematic parameter is the best predictor of the displacement area of the COP measured during the stance phase of the stair ascent. Methods Twenty-nine females with PFP and 25 asymptomatic pain-free females underwent three-dimensional kinematic and COP analyses during stair ascent. Between-group comparisons were made using independent t-tests. Regression models were performed to identify the capability of each kinematic factor in predicting the displacement area of the COP. Results Reduced knee flexion and displacement area of the COP as well as increased peak hip adduction and peak rearfoot eversion were observed in individuals with PFP as compared to controls. Peak hip adduction was the best predictor of the displacement area of the COP (r 2 =23.4%). Conclusions The excessive hip adduction was the biggest predictor of the displacement area of the COP. Clinical relevance Based on our findings, proximally targeted interventions may be of major importance for the functional reestablishment of females with PFP.

Pedestrians, motorcyclists, and occupants of vehicle involved in side impacts can suffer lateral impacts at the shoulder with sufficiently high forces to fracture the clavicle. While some previous studies have developed a force tolerance for the clavicle, this study examines the clavicle under compression forces, both under dynamic and quasi-static loading conditions and then the experimental fracture patterns are compared with those identified in actual road traffic crashes. The quasi-static and dynamic tests were conducted in 24 clavicles from 14 donors aged 14–56 (11 males and 3 females, mean age [Formula: see text]). Clavicles were tested under compression forces until complete fracture. Probability of fracture is around 50% for 2335[Formula: see text]N in the quasi-static case (low strain rate) and 3045[Formula: see text]N in the dynamic case (high strain rate). In addition, risk curves for fracture have been computed from the sample. The experiments showed large differences in the peak force both in quasi-static ([Formula: see text][Formula: see text]N) and dynamic ([Formula: see text][Formula: see text]N) tests, but the displacement at the peak force was very similar ([Formula: see text][Formula: see text]mm in quasi-static and [Formula: see text][Formula: see text]mm in dynamic tests). Thus, a stiffer behavior of the specimens was observed for the dynamic tests. The Probability Density Function for dynamic and quasi-static cases differ significantly ([Formula: see text]-value [Formula: see text]). The fracture patterns were consistent with principles of structural mechanics, predicting that the fracture will occur at points near to the highest bending moment point, and with the fractures observed in real road crashes.

Part I of these special issue concludes the selection concentraiting on the Applications on Mechanics in Medicine and Biology.

[Abstract] Generalized ligamentous hyperlaxity (GLH) has been shown to predispose an individual to a number of orthopaedic conditions. Little is known about how GLH affects people’ foot health-related quality of life. This study analyses a sample of people with GLH and people without GLH with normalised reference values of the scores collected with regard to using the Foot Health Status Questionnaire (FSHQ). A total of 100 respondents with mean age of 22.69 ± 3.78 years old, who attended a health centre were classified as GLH (n = 50) or non-GLH (n = 50). The GLH was determined of the patients with and without GLH using assessment with Beighton tool and the scores on the FHSQ were compared. The control group recorded higher scores in the First Section for foot pain, foot function and general foot health, and lower scores in footwear. In the Second Section, they obtained higher scores in social capacity and lower scores in physical activity, vigour and general health. Differences between the two groups were evaluated through a t-test for independent samples, showing statistical significance (P

Introduction: Postural control is a multidimensional construct modulated by the integration of sensory information and muscular activity. One of the challenges in clinical practice and scientific research is the postural data collection of objective control data. Thus, baropodometry can be a promising instrument for analysis. Objective: To evaluate the absolute and relative reliability of baropodometry by means of test-retest in young asymptomatic subjects during semi-static and dynamic analysis. Methods: This is a methodological study, approved by the Research Ethics Committee of UFJF (1,803,411). Sample selection was performed by convenience. Healthy individuals aged 18 to 35 years were included in the study without gender restriction. Participants with pain or any clinical signs of overload which led to unfeasible collection were excluded from the analysis. The variables analyzed were contact surface, maximum and mean pressure, index bow, pressure center and pressure areas in the forefoot, midfoot and hindfoot. Results: 33 individuals (total of 66 feet) participated in this study. The mean body mass of the participants was 63.0 ± 9.9kg, height of 163.4 ± 30.1cm, BMI of 23.7 ± 2.8 kg/m2. It was observed that five out of the eight variables evaluated in the semi-static analysis presented high reliability (≥ 0.70). On the other hand, the reproducibility of the measures in the dynamic analysis was low to moderate (≤ 0.69). Conclusion: Baropodometry findings should be interpreted with caution in clinical practice and in scientific research. It is suggested that complementary assessments be made for decision-making assistance. Resumo Introdução: O controle postural é um constructo multidimensional modulado pela integração de informações sensoriais e atividade muscular. Um dos desafios na prática clínica e em pesquisas científicas é a obtenção de dados objetivos do controle postural. Baseando-se nessa premissa, a baropodometria pode ser um instrumento promissor para esta análise. Objetivo: Avaliar a confiabilidade absoluta e relativa por meio de teste-reteste da baropodometria em indivíduos jovens assintomáticos durante análise semi estática e dinâmica. Métodos: Trata-se de um estudo metodológico, aprovado pelo Comitê de Ética em pesquisa da UFJF (parecer 1.803.411). A seleção da amostra foi por conveniência. Foram incluídos indivíduos hígidos de 18 a 35 anos sem restrição de gênero e excluídos participantes com queixa álgica ou qualquer sinal clínico de sobrecarga que inviabilizasse a coleta. As variáveis analisadas foram superfície de contato, pressão máxima e média, arco index, centro de pressão e as áreas de pressão no antepé, mediopé e retropé. Resultados: Participaram do estudo 33 indivíduos (66 pés). A média de massa corporal dos participantes foi de 63,0 ± 9,9 kg, estatura de 163,4 ± 30,1 cm, IMC de 23,7 ± 2,8 kg/m2 e número do calçado 38,0 ± 2,1. Observamos que das oito variáveis avaliadas na análise semi estática, cinco apresentaram confiabilidade alta (CCI ≥ 0.70). Por outro lado, a reprodutibilidade das medidas na análise dinâmica foi de baixa à moderada (CCI ≤ 0.69). Conclusão: Os achados da baropodometria devem ser interpretados com cautela na prática clínica e em pesquisa científica. Sugere-se que sejam realizadas avaliações complementares para o auxílio de tomada de decisões.

Objective The purpose of this review was to identify different kinematic characteristics between the movements of sit-to-stand-to-sit, sit-to-stand, or stand-to-sit of individuals with and without low back pain (LBP). Methods A systematic search was conducted on scientific databases. The analyzed kinematic variables were duration of the movement, reproduction of the movement, ranges of motion, velocity, and acceleration. The studies were appraised for methodological quality using the Downs & Black scale and for the level of evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results After all screening stages, this systematic review comprised 8 cross-sectional studies. When comparing the patients with LBP vs controls, patients with LBP take longer to perform the sit-to-stand-to-sit, sit-to-stand, and stand-to sit movements (eg, 9.33 ± 1.49 seconds vs 8.29 ± 1.23 seconds in the sit-to-stand-to-sit movement), show decreased mobility of the lumbar spine (eg, 26.21° ± 8.76° vs 32.07° ± 6.77° in the sit-to-stand-to-sit movement) and the hip (eg, 51.0° vs 77.25° in the sit-to-stand movement), present decreased velocity of the trunk (eg, 95.31° ± 25.13°/s vs 138.23° ± 23.42°/s in the sit-to-stand-to-sit movement) and the hip (eg, 46° ± 13°/s vs 69° ± 13°/s in the sit-to-stand movement), and decreased overall acceleration of the trunk (eg, 280.19° ± 113.08°/s2 vs 460.16° ± 101.49°/s2 in the sit-to-stand-to-sit movement), besides presenting greater variability of the trunk (eg, 5.53° ± 0.48° vs 4.32° ± 0.46° in the sit-to-stand movement). Conclusion There are kinematic alterations in the lumbar spine, the hip, and the trunk of patients with LBP. However, information about pelvic and overall trunk mobility, velocity, and acceleration of the lumbar spine; and mobility, speed, and acceleration of hip and pelvis remain incipient in individuals with LBP. Based on the Grading of Recommendations Assessment, Development, and Evaluation criteria, the results of this review indicate that there is low scientific evidence on the characteristics of the kinematic variables (duration of the movement, reproduction of the movement, range of motion, velocity, and acceleration) of the trunk, lumbar spine, pelvis, and hip in patients with LBP.

Objectives To check how a thermal IR camera can check skin temperature in gastrocnemius‐soleus equinus condition and non‐gastrocnemius‐soleus condition in youth soccer players and thus detect association between the extensibility of the triceps surae (with gastrocnemius‐soleus equinus and non‐gastrocnemius‐soleus equinus) and the muscle temperature pattern. Design A cross‐sectional study secondary level of care. Methods Sample from an elite soccer academy in Madrid (Spain) 35 healthy male subjects (youth soccer players) age 12.82 ± 1.07 years, height 158.68 ± 10.79 cm, weight 49.19 ± 9.45 kg, body mass index 19.41 ± 2.25. The exclusion criteria were the presence of musculoskeletal and joint injuries, pelvic pain, ankle sprains, low back pain and use of drugs in the previous week, and scoliosis. Results Temperature value for gastrocnemius muscles and Achilles tendon were assessed in 35 youth soccer players from an academia before and after training in both 12 gastrocnemius‐soleus equinus and 23 non‐gastrocnemius‐soleus equinus soccer players conditions. State absolute for gastrocnemius soleus condition obtained a 0.34 value (0.19–0.5); we found a significant increase in temperature among these conditions for the gastrocnemius (P = 0.028) and the Achilles tendon (P = 0.007) (confidence interval 95%). The temperature of gastrocnemius‐soleus equinus for gastrocnemius and Achilles tendon was increased more than non‐gastrocnemius‐soleus equinus in youth soccer players. Conclusions IR imaging captured temperature is associated with muscle pattern activation for lower limb. Based on our findings, we propose that infrared thermography evaluation of the gastrocnemius and Achilles tendon is suitable to differ gastrocnemius‐soleus equinus and non‐gastrocnemius‐soleus equinus conditions in youth soccer players. Sin financiación 5.113 JCR (2018) Q1, 6/66 Dermatology 1.647 SJR (2018) Q1, 7/146 Dermatology, 47/298 Infectious Diseases No data IDR 2018 UEM

Pelvic organ prolapse (POP) has borrowed principles of treatment from hernia repair and in the last two decades we saw reinforcement materials to treat POP with good outcomes in terms of anatomy but with alarming complication rates. Polypropylene meshes to specifically treat POP have been withdrawn from market by manufactures and a blank space was left to be filled with new materials. Macroporous monofilament meshes are ideal candidates and electrospinning emerged as a reliable method capable of delivering production reproducibility and customization. In this review, we point out some pathways that seem logical to be followed but have been only researched in last couple of years.