The evaluation of anticipatory postural adjustments (APAs) requires high-cost and complex handling systems, only available at research laboratories. New alternative methods are being developed in this field, on the other hand, to solve this issue and allow applicability in clinic, sport and hospital environments. The objective of this study was to validate an app for mobile devices to measure the APAs during gait initiation by comparing the signals obtained from cell phones using the Momentum app with measurements made by a kinematic system. The center-of-mass accelerations of a total of 20 healthy subjects were measured by the above app, which read the inertial sensors of the smartphones, and by kinematics, with a reflective marker positioned on their lumbar spine. The subjects took a step forward after hearing a command from an experimenter. The variables of the anticipatory phase, prior to the heel-off and the step phase, were measured. In the anticipatory phase, the linear correlation of all variables measured by the two measurement techniques was significant and indicated a high correlation between the devices (APAonset: r = 0.95, p < 0.0001; APAamp: r = 0.71, p = 0.003, and PEAKtime: r = 0.95, p < 0.0001). The linear correlation between the two measurement techniques for the step phase variables measured by ques was also significant (STEPinterval: r = 0.56, p = 0.008; STEPpeak1: r = 0.79, p < 0.0001; and STEPpeak2: r = 0.64, p < 0.0001). The Bland–Altman graphs indicated agreement between instruments with similar behavior as well as subjects within confidence limits and low dispersion. Thus, using the Momentum cell phone application is valid for the assessment of APAs during gait initiation compared to the gold standard instrument (kinematics), proving to be a useful, less complex, and less costly alternative for the assessment of healthy individuals.

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Introdução: Por comprometer as células de defesa do organismo, o Vírus da Imunodeficiência Humana torna o indivíduo vulnerável ao aparecimento de diversas doenças, entre elas a neurotoxoplasmose. Objetivo: Verificar a influência de um protocolo de hidroterapia no equilíbrio dinâmico e nas atividades de vida diária de pacientes com neurotoxoplasmose associada à Síndrome da Imunodeficiência Adquirida (SIDA). Métodos: Participaram 15 voluntários, três (20%) do sexo feminino e 12 (80%) do masculino, com média de idade de 37,44±5,5 anos e diagnóstico de neurotoxoplasmose decorrente da SIDA, cadastrados na Unidade de Referência Especializada em Doenças Infectocontagiosas Parasitárias Especiais. Foram submetidos à avaliação do equilíbrio dinâmico pelo Índice de Marcha Dinâmico e à avaliação das atividades de vida diária pelo Índice de Barthel, pré-e pós-hidroterapia, em piscina à temperatura média de 35°C, três vezes por semana em dias alternados, durante 50 minutos, totalizando oito semanas, ou seja, 24 sessões. Foi utilizado o teste de Shapiro-Wilk para análise de variâncias do Índice de Marcha Dinâmica e do Índice de Barthel, e o teste t de Student para as comparações pré e pós-tratamento e nível de significância de α=0.05. Resultados: O equilíbrio dinâmico, considerando o escore total, apresentou significância estatística (p<0,0001), quando comparado pós-teste (20,3±2,5) em relação ao pré-teste (13,2±3,2). Quanto às atividades de vida diária, foi evidenciado valor estatisticamente significante (p=0,049) no pós-teste (98,8±2.2) quando comparado ao pré-teste (95,6±3.9). Conclusão: Neste estudo, o protocolo de hidroterapia melhorou o equilíbrio dinâmico e as atividades de vida diária de pacientes com neurotoxoplasmose associada à SIDA.Palavras-chave: toxoplasmose cerebral; Síndrome da Imunodeficiência Adquirida; fisioterapia; hidroterapia. ABSTRACT Introduction:For compromising the defense cells of the body, the Human Immunodeficiency Virus makes the individual vulnerable to the emergence of various diseases, including the neurotoxoplasmosis. Objective: To determine the effect of a hydrotherapy protocol in dynamic balance and the activities of daily living of patients with cerebral toxoplasmosis associated with the Acquired Immuno Deficiency Syndrome (AIDS). Methods: 15 volunteers participated, three (20%) were female and 12 of them (80%) were male; mean age 37.44±5.5 years, diagnosed with cerebral toxoplasmosis resulting from AIDS registered in Specialized Reference Unit on Infectious Diseases Parasitic Infectious Specials. Underwent evaluation of dynamic balance by the Dynamic Gait Index and the activities of daily living by Barthel Index, pre and post hydrotherapy, in the pool at an average temperature of 35°C, 3 times per week on alternate days, lasting 50 minutes, a total of 8 weeks or 24 sessions. We used the Shapiro-Wilk test for analysis of the Dynamic Gait Index and Barthel Index variances, and T Student test for pre and post-treatment comparison and significance level of α=0.05. Results: Total score of dynam...

Introduction: Evidence supports the importance of efficient postural control to improve performance in sports. This involves the use of strategies such as anticipatory posture adjustments and compensatory adjustments. Technology makes analysis and assessments in sports cheaper, while being valid and reliable compared to the gold-standard assessment equipment. Objectives: This article aimed to test the validity and reliability of signals extracted from the sensor’s accelerometer (Metamotion C), by comparing it to the data obtained from the gold-standard equipment (a three-dimensional video-motion-capture system). Design: Observational, cross-sectional study. Methods: We exposed 20 healthy young standing people to the pendulum impact paradigm, which consisted of predictable anteroposterior disturbances applied at the shoulder level. In order to measure this, we observed the acceleration of the center of mass in the anticipatory and compensatory phase of the disturbance and compared the signals of the two devices (Metamotion C and a motion-capture system). Results: The validation results showed the significant linear correlation of all variables with a moderate to large correlation of r ≥ 0.5 between the devices. In contrast, the reliability results between sessions obtained by filming were all significant and above 0.75, indicating excellent reliability. The APAonset variable had a reasonable to high intra-class correlation in the anticipatory phase. In the compensatory phase, the CPAtime variable showed an excellent correlation. Conclusions: Metamotion C proved reasonably valid and highly reliable in measuring the center of mass acceleration compared to the camera system in both the anticipatory and compensatory phases.

Background Step initiation involves anticipatory postural adjustments (APAs) that can be measured using inertial measurement units (IMUs) such as accelerometers. However, previous research has shown heterogeneity in terms of the population studied, sensors used, and methods employed. Validity against gold standard measurements was only found in some studies, and the weight of the sensors varied from 10 to 110 g. The weight of the device is a crucial factor to consider when assessing APAs, as APAs exhibit significantly lower magnitudes and are characterized by discrete oscillations in acceleration paths. Objective This study aims to validate the performance of a commercially available ultra-light sensor weighing only 5.6 g compared to a 168-g smartphone for measuring APAs during step initiation, using a video capture kinematics system as the gold standard. The hypothesis is that APA oscillation measurements obtained with the ultra-light sensor will exhibit greater similarity to those acquired using video capture than those obtained using a smartphone. Materials and Methods Twenty subjects were evaluated using a commercial lightweight MetaMotionC accelerometer, a smartphone and a system of cameras—kinematics with a reflective marker on lumbar vertebrae. The subjects initiated 10 trials of gait after a randomized command from the experimenter and APA variables were extracted: APAonset, APAamp, PEAKtime. A repeated measures ANOVA with post-hoc test analyzed the effect of device on APA measurements. Bland–Altman plots were used to evaluate agreement between MetaMotionC, smartphone, and kinematics measurements. Pearson’s correlation coefficients were used to assess device correlation. Percentage error was calculated for each inertial sensor against kinematics. A paired Student’s t-test compared th devices percentage error. Results The study found no significant difference in temporal variables APAonset and PEAKtime between MetaMotionC, smartphone, and kinematic instruments, but a significant difference for variable APAamp, with MetaMotionC yielding smaller measurements. The MetaMotionC had a near-perfect correlation with kinematic data in APAonset and APAamp, while the smartphone had a very large correlation in APAamp and a near-perfect correlation in APAonset and PEAKtime. Bland–Altman plots showed non-significant bias between smartphone and kinematics for all variables, while there was a significant bias between MetaMotionC and kinematics for APAamp. The percentage of relative error was not significantly different between the smartphone and MetaMotionC. Conclusions The temporal analysis can be assessed using ultralight sensors and smartphones, as MetaMotionC and smartphone-based measurements have been found to be valid compared to kinematics. However, caution should be exercised when using ultralight sensors for amplitude measurements, as additional research is necessary to determine their effectiveness in this regard.