Browsing by Author "Machado, Leandro"
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- Accuracy and repeatability of the gait analysis by the WalkinSense systemPublication . P. de Castro, Marcelo; Meucci, Marco; Soares, Denise P.; Fonseca, Pedro; Borgonovo-Santos, Márcio; Sousa, Filipa; Machado, Leandro; Villas-Boas, João PauloWalkinSense is a new device designed to monitor walking. The aim of this study was to measure the accuracy and repeatability of the gait analysis performed by the WalkinSense system. Descriptions of values recorded by WalkinSense depicting typical gait in adults are also presented. A bench experiment using the Trublu calibration device was conducted to statically test the WalkinSense. Following this, a dynamic test was carried out overlapping the WalkinSense and the Pedar insoles in 40 healthy participants during walking. Pressure peak, pressure peak time, pressure-time integral, and mean pressure at eight-foot regions were calculated. In the bench experiments, the repeatability (i) among the WalkinSense sensors (within), (ii) between two WalkinSense devices, and (iii) between the WalkinSense and the Trublu devices was excellent. In the dynamic tests, the repeatability of the WalkinSense (i) between stances in the same trial (within-trial) and (ii) between trials was also excellent (ICC > 0.90). When the eight-foot regions were analyzed separately, the within-trial and between-trials repeatability was good-to-excellent in 88% (ICC > 0.80) of the data and fair in 11%. In short, the data suggest that the WalkinSense has good-to-excellent levels of accuracy and repeatability for plantar pressure variables.
- Analysis of the backpack loading efects on the human gaitPublication . Machado, Leandro; Castro, Marcelo P. de; Abreu, Sofia; Sousa, Helena; Gonçalves, Pedro; Sousa, Filipa; Santos, Rubim; Pinto, Viviana; Vaz, Mário; Vilas-Boas, João P.Gait is a simple activity of daily life and one of the main abilities of the human being. Often during leisure, labour and sports activities, loads are carried over (e.g. backpack) during gait. These circumstantial loads can generate instability and increase biomechanicalstress over the human tissues and systems, especially on the locomotor, balance and postural regulation systems. According to Wearing (2006), subjects that carry a transitory or intermittent load will be able to find relatively efficient solutions to compensate its effects.
- Analysis of the backpack loading effects on the human gaitPublication . Machado, Leandro; P. de Castro, Marcelo; Abreu, Sofia; Sousa, Helena; Gonçalves, Pedro; Sousa, Filipa; Santos, Rubim; Pinto, Viviana; Vaz, Mário; Boas, J. Paulo VilasGait is a simple activity of daily life and one of the main abilities of the human being. Often during leisure, labour and sports activities, loads are carried over (e.g. backpack) during gait. These circumstantial loads can generate instability and increase biomechanical stress over the human tissues and systems, especially on the locomotor, balance and postural regulation systems. According to Wearing (2006), subjects that carry a transitory or intermittent load will be able to find relatively efficient solutions to compensate its effects. These are dependent upon the walking distance and of the load characteristics - size, weight and location relatively to the body (Hsiang, 2002).Thus, these solutions should become a concerning factor (Koh, 2009) and a topic of scientific research, particularly in what concerns the inventory of its biomechanical effects and the possible strategies to be developed in order to minimize its effects. The aim of the present study was to analyze the effects of an occasional dorso-lombar load during the gait through the use of a backpack.
- Biomechanical Characterization of Comfort Footwear using Gait AnalysisPublication . Flores, Andreia; Marques, Maria Arcelina; Fonseca, Pedro; Machado, Leandro; Vaz, MárioComfort footwear has unique characteristics fundamental to people looking for this type of shoe, namely foot support, flexibility, stability, lightweight, cushioning, traction, etc. [1]. They are usually preferred mainly by elder, overweighed or people with feet problems [2]. It is known that the shoe can modify gait behavior [3]. The purpose of this study was to evaluate posture and gait by comparing barefoot and shoe wearing circumstances to assess the real effect of the comfort footwear under study.
- Efeito da sobrecarga permanente e ocasional nos parâmetros cinéticos da marchaPublication . Castro, Marcelo; Abreu, Sofia; Sousa, Helena; Figueiredo, Cristina; Machado, Leandro; Santos, Rubim; Vilas-Boas, João PauloProposta do presente estudo foi comparar o efeito da sobrecarga permanente (pessoas obesas) e ocasional (mochileiros) nos parâmetros cinéticos da marcha. Foram observadas adaptação no padrão da marcha nos indivíduos quando submetidos a sobrecarga.
- Force and pressure analysis during occasional loaded gaitPublication . Castro, Marcelo Peduzzi; Santos, Rubim; Abreu, Sofia; Sousa, Helena; Machado, Leandro; Vilas Boas, JoãoThe aim of this study was to compare the ground reaction forces and plantar pressure parameters between unloaded and occasional loaded gait. The ground reaction forces and plantar pressure of 60 participants were recorded during unloaded and occasional loaded gait (wearing a backpack which raises the participant´s body mass index to 30). The results indicate an overall increase of forces and plantar pressure during occasional loaded gait where the absolute values were analyzed (p<0.05), while the normalized values suggested a non-linear relation between backpack mass and plantar pressure increases, where the medial midfoot and toes were more required while the lateral rearfoot was less during loaded gait (p<0.05). Also, during loaded gait the magnitude of impact and propulsive forces decreased and the shear forces increased more than proportion of the load. These data suggest a different pattern of plantar pressure distribution and forces during occasional loaded when compared to unloaded gait
- Ground reaction forces and plantar pressure distribution during occasional loaded gaitPublication . Castro, Marcelo Peduzzi; Abreu, Sofia; Sousa, Helena; Machado, Leandro; Santos, Rubim; Vilas Boas, JoãoThis study compared the ground reaction forces (GRF) and plantar pressures between unloaded and occasional loaded gait. The GRF and plantar pressures of 60 participants were recorded during unloaded gait and occasional loaded gait (wearing a backpack that raised their body mass index to 30); this load criterion was adopted because is considered potentially harmful in permanent loaded gait (obese people). The results indicate an overall increase (absolute values) of GRF and plantar pressures during occasional loaded gait (p < 0.05); also, higher normalized (by total weight) values in the medial midfoot and toes, and lower values in the lateral rearfoot region were observed. During loaded gait the magnitude of the vertical GRF (impact and thrust maximum) decreased and the shear forces increased more than did the proportion of the load (normalized values). These data suggest a different pattern of GRF and plantar pressure distribution during occasional loaded compared to unloaded gait.
- In-shoe plantar pressures and ground reaction forces during overweight adults' overground walkingPublication . Castro, Marcelo Peduzzi; Abreu, Sofia; Sousa, Helena; Machado, Leandro; Santos, Rubim; Vilas Boas, JoãoPurpose: Because walking is highly recommended for prevention and treatment of obesity and some of its biomechanical aspects are not clearly understood for overweight people, we compared the absolute and normalized ground reaction forces (GRF), plantar pressures, and temporal parameters of normal-weight and overweight participants during overground walking. Method: A force plate and an in-shoe pressure system were used to record GRF, plantar pressures (foot divided in 10 regions), and temporal parameters of 17 overweight adults and 17 gender-matched normal-weight adults while walking. Results: With high effect sizes, the overweight participants showed higher absolute medial-lateral and vertical GRF and pressure peaks in the central rearfoot, lateral midfoot, and lateral and central forefoot. However, analyzing normalized (scaled to body weight) data, the overweight participants showed lower vertical and anterior-posterior GRF and lower pressure peaks in the medial rearfoot and hallux, but the lateral forefoot peaks continued to be greater compared with normal-weight participants. Time of occurrence of medial-lateral GRF and pressure peaks in the midfoot occurred later in overweight individuals. Conclusions: The overweight participants adapted their gait pattern to minimize the consequences of the higher vertical and propulsive GRF in their musculoskeletal system. However, they were not able to improve their balance as indicated by medial-lateral GRF. The overweight participants showed higher absolute pressure peaks in 4 out of 10 foot regions. Furthermore, the normalized data suggest that the lateral forefoot in overweight adults was loaded more than the proportion of their extra weight, while the hallux and medial rearfoot were seemingly protected.
- Influence of pressure-relief insoles developed for loaded gait (backpackers and obese people) on plantar pressure distribution and ground reaction forcesPublication . Peduzzi de Castro, Marcelo; Abreu, Sofia; Pinto, Viviana; Santos, Rubim; Machado, Leandro; Vaz, Mario; Vilas-Boas, João PauloThe aims of this study were to test the effects of two pressure relief insoles developed for backpackers and obese people on the ground reaction forces (GRF) and plantar pressure peaks during gait; and to compare the GRF and plantar pressures among normal-weight, backpackers, and obese participants. Based on GRF, plantar pressures, and finite element analysis two insoles were manufactured: flat cork-based insole with (i) corkgel in the rearfoot and forefoot (SLS1) and with (ii) poron foam in the great toe and lateral forefoot (SLS2). Gait data were recorded from 21 normal-weight/backpackers and 10 obese participants. The SLS1 did not influence the GRF, but it relieved the pressure peaks for both backpackers and obese participants. In SLS2 the load acceptance GRF peak was lower; however, it did not reduce the plantar pressure peaks. The GRF and plantar pressure gait pattern were different among the normal-weight, backpackers and obese participants.
- Lower limb kinematics of transfemoral amputees gait: a principal component analysis approachesPublication . Soares, Denise; Castro, Marcelo; Mendes, Emília; Machado, LeandroThe purpose of this study was to compare the gait waveforms of the ankle, knee and hip in sagital plane kinematic variables between both limbs of transfemoral (TF) amputees and able-bodied subjects using principal component analysis (PCA). Fourteen TF amputees and 20 able-bodied subjects were enrolled in the study. The ankle, knee and hip sagittal plane kinematics were recorded for the able-bodied participants, for the amputed limb and sound limb during self-selected speed gait. The results showed that both TF's lower limbs presented statistical differences in all sudied joints when compared to the able-bodied participants, in different phases in the gait cycle. Also PCA analysis seems to be a powerful tool to descriminate gait parameters considering the whole waveform of the variables involved.