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1.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202659

RESUMO

Human recognition technology is a task that determines the people existing in images with the purpose of identifying them. However, automatic human recognition at night is still a challenge because of its need to align requirements with a high accuracy rate and speed. This article aims to design a novel approach that applies integrated face and gait analyses to enhance the performance of real-time human recognition in TIR images at night under various walking conditions. Therefore, a new network is proposed to improve the YOLOv3 model by fusing face and gait classifiers to identify individuals automatically. This network optimizes the TIR images, provides more accurate features (face, gait, and body segment) of the person, and possesses it through the PDM-Net to detect the person class; then, PRM-Net classifies the images for human recognition. The proposed methodology uses accurate features to form the face and gait signatures by applying the YOLO-face algorithm and YOLO algorithm. This approach was pre-trained on three night (DHU Night, FLIR, and KAIST) databases to simulate realistic conditions during the surveillance-protecting areas. The experimental results determined that the proposed method is superior to other results-related methods in the same night databases in accuracy and detection time.


Assuntos
Face , Reconhecimento Psicológico , Algoritmos , Marcha , Humanos , Tecnologia
2.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202786

RESUMO

The high prevalence of falls and the enormous impact they have on the elderly population is a cause for concern. We aimed to develop a walking-monitor gait pattern (G-STRIDE) for older adults based on a 6-axis inertial measurement (IMU) with the application of pedestrian dead reckoning algorithms and tested its structural and clinical validity. A cross-sectional case-control study was conducted with 21 participants (11 fallers and 10 non-fallers). We measured gait using an IMU attached to the foot while participants walked around different grounds (indoor flooring, outdoor floor, asphalt, etc.). The G-STRIDE consisted of a portable inertial device that monitored the gait pattern and a mobile app for telematic clinical analysis. G-STRIDE made it possible to measure gait parameters under normal living conditions when walking without assessing the patient in the outpatient clinic. Moreover, we verified concurrent validity with convectional outcome measures using intraclass correlation coefficients (ICCs) and analyzed the differences between participants. G-STRIDE showed high estimation accuracy for the walking speed of the elderly and good concurrent validity compared to conventional measures (ICC = 0.69; p < 0.000). In conclusion, the developed inertial-based G-STRIDE can accurately classify older people with risk to fall with a significance as high as using traditional but more subjective clinical methods (gait speed, Timed Up and Go Test).


Assuntos
Acidentes por Quedas , Dispositivos Eletrônicos Vestíveis , Idoso , Estudos de Casos e Controles , Estudos Transversais , Marcha , Humanos , Projetos Piloto , Equilíbrio Postural , Estudos de Tempo e Movimento , Caminhada
3.
Sensors (Basel) ; 21(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206289

RESUMO

Pedometers are popular for counting steps as a daily measure of physical activity, however, errors as high as 96% have been reported in previous work. Many reasons for pedometer error have been studied, including walking speed, sensor position on the body and pedometer algorithm, demonstrating some differences in error. However, we hypothesize that the largest source of error may be due to differences in the regularity of gait during different activities. During some activities, gait tends to be regular and the repetitiveness of individual steps makes them easy to identify in an accelerometer signal. During other activities of everyday life, gait is frequently semi-regular or unstructured, which we hypothesize makes it difficult to identify and count individual steps. In this work, we test this hypothesis by evaluating the three most common types of pedometer algorithm on a new data set that varies the regularity of gait. A total of 30 participants were video recorded performing three different activities: walking a path (regular gait), conducting a within-building activity (semi-regular gait), and conducting a within-room activity (unstructured gait). Participants were instrumented with accelerometers on the wrist, hip and ankle. Collectively, 60,805 steps were manually annotated for ground truth using synchronized video. The main contribution of this paper is to evaluate pedometer algorithms when the consistency of gait changes to simulate everyday life activities other than exercise. In our study, we found that semi-regular and unstructured gaits resulted in 5-466% error. This demonstrates the need to evaluate pedometer algorithms on activities that vary the regularity of gait. Our dataset is publicly available with links provided in the introduction and Data Availability Statement.


Assuntos
Actigrafia , Marcha , Algoritmos , Humanos , Caminhada , Velocidade de Caminhada
4.
Sensors (Basel) ; 21(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209518

RESUMO

This study aims to measure and compare spatiotemporal gait parameters in nineteen subjects using a full wearable inertial mocap system Xsens (MVN Awinda, Netherlands) and a photoelectronic system one-meter OptoGaitTM (Microgait, Italy) on a treadmill imposing a walking speed of 5 km/h. A total of eleven steps were considered for each subject constituting a dataset of 209 samples from which spatiotemporal parameters (SPT) were calculated. The step length measurement was determined using two methods. The first one considers the calculation of step length based on the inverted pendulum model, while the second considers an anthropometric approach that correlates the stature with an anthropometric coefficient. Although the absolute agreement and consistency were found for the calculation of the stance phase, cadence and gait cycle, from our study, differences in SPT were found between the two systems. Mean square error (MSE) calculation of their speed (m/s) with respect to the imposed speed on a treadmill reveals a smaller error (MSE = 0.0008) using the OptoGaitTM. Overall, our results indicate that the accurate detection of heel strike and toe-off have an influence on phases and sub-phases for the entire acquisition. Future study in this domain should investigate how to design and integrate better products and algorithms aiming to solve the problematic issues already identified in this study without limiting the user's need and performance in a different environment.


Assuntos
Caminhada , Dispositivos Eletrônicos Vestíveis , Fenômenos Biomecânicos , Marcha , Humanos , Itália , Países Baixos
5.
Sensors (Basel) ; 21(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209917

RESUMO

Functional electrical stimulation (FES) walking interventions have demonstrated improvements to gait parameters; however, studies were often confined to stimulation of one or two muscle groups. Increased options such as number of muscle groups targeted, timing of stimulation delivery, and level of stimulation are needed to address subject-specific gait deviations. We aimed to demonstrate the feasibility of using a FES system with increased stimulation options during walking in children with cerebral palsy (CP). Three physical therapists designed individualized stimulation programs for six children with CP to target participant-specific gait deviations. Stimulation settings (pulse duration and current) were tuned to each participant. Participants donned our custom FES system that utilized gait phase detection to control stimulation to lower extremity muscle groups and walked on a treadmill at a self-selected speed. Motion capture data were collected during walking with and without the individualized stimulation program. Eight gait metrics and associated timing were compared between walking conditions. The prescribed participant-specific stimulation programs induced significant change towards typical gait in at least one metric for each participant with one iteration of FES-walking. FES systems with increased stimulation options have the potential to allow the physical therapist to better target the individual's gait deviations than a one size fits all device.


Assuntos
Paralisia Cerebral , Terapia por Estimulação Elétrica , Transtornos Neurológicos da Marcha , Criança , Estimulação Elétrica , Marcha , Humanos , Caminhada
6.
F1000Res ; 10: 214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249338

RESUMO

Background: Despite the potential benefits, the effects of Hybrid Assistive Limb (HAL) gait training on changes in neuromuscular activation that accompany functional gains in individuals with spinal muscular atrophy (SMA) type III is not well known. In this article, we quantify the effects of HAL gait training on spatial muscle activity patterns in a patient with SMA type III using multi-channel surface electromyography (SEMG). Methods: A 21-years old male (168 cm, 47.8 kg) with spinal muscular atrophy type III, when diagnosed at 18-years old by genetic screening, participated in this case study. Although he presented with forearm distal muscle weakness, atrophy of the intrinsic muscles of the hand, and neuromuscular fatigue, his activities of daily living is independent. The patient underwent a separate, single 33-minute session of both HAL and treadmill gait training. To evaluate the coefficient of variation (CoV) of force and alterations in the SEMG spatial distribution patterns, modified entropy and CoV of root mean square (RMS) were calculated from the vastus lateralis (VL) muscle before and after the intervention of HAL and treadmill gait training. Each training session was separated by a period of one month to avoid cross-over effects. Results: There was a greater decrease in the ΔCoV of force and an increase in the magnitude of whole VL muscle activation from pre-intervention to post-intervention with the HAL gait training as compared to the treadmill gait training. In response to only HAL gait training, the CoV of RMS was higher, and the modified entropy was lower post-intervention than pre-intervention. Conclusions: Our results support the notion that HAL gait training has a positive benefit on motor output not only in the magnitude of SEMG generated but also the patterns of neural activation.


Assuntos
Atividades Cotidianas , Atrofias Musculares Espinais da Infância , Adolescente , Adulto , Marcha , Humanos , Masculino , Músculos , Caminhada , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-34205457

RESUMO

BACKGROUND: Trunk impairment produces disorders of motor control, balance and gait. Core stability exercises (CSE) are a good strategy to improve local strength of trunk, balance and gait. Methods and analysis: This is a single-blind multicenter randomized controlled trial. Two parallel groups are compared, and both perform the same type of therapy. A control group (CG) (n = 110) performs conventional physiotherapy (CP) (1 h per session) focused on improving balance. An experimental group (EG) (n = 110) performs CSE (30 min) in addition to CP (30 min) (1 h/session in total). EG is divided in two subgroups, in which only half of patients (n = 55) perform CSE plus transcutaneous electrical nerve stimulation (TENS). Primary outcome measures are dynamic sitting, assessed by a Spanish version of Trunk Impairment Scale and stepping, assessed by Brunel Balance Assessment. Secondary outcomes are postural control, assessed by Postural Assessment Scale for Stroke patients; standing balance and risk of fall assessed by Berg Balance Scale; gait speed by BTS G-Walk (accelerometer); rate of falls, lower-limb spasticity by Modified Ashworth Scale; activities of daily living by Barthel Index; and quality of life by EQ-5D-5L. These are evaluated at baseline (T0), at three weeks (T1), at five weeks (end of the intervention) (T2), at 17 weeks (T3) and at 29 weeks (T4). Study duration per patient is 29 weeks (a five-week intervention, followed by a 24-week post-intervention).


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Atividades Cotidianas , Terapia por Exercício , Marcha , Humanos , Estudos Multicêntricos como Assunto , Equilíbrio Postural , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego , Postura Sentada , Resultado do Tratamento
8.
N Z Med J ; 134(1538): 44-51, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34239144

RESUMO

AIMS: Stress plays a key role in Parkinson's disease (PD) by acting on the dopaminergic system and worsening patients' motor function. The impact of New Zealand's strict lockdown measures to contain COVID-19 on perceived stress and PD motor symptoms remains unknown. Here we examined the relationship between perceived levels of stress, changes in physical activity levels and PD motor symptoms during lockdown. METHODS: During lockdown, 134 participants with PD and 49 controls completed a survey assessing perceived stress, self-reported changes in PD motor symptoms and physical activity duration and intensity prior to and during lockdown. RESULTS: Perceived stress was higher in PD than controls, and in those reporting a worsening of tremor, balance/gait, dyskinesia and bradykinesia compared to those indicating no change during the COVID-19 lockdown. These effects were not modulated by physical activity. CONCLUSIONS: Reducing stressors may be an important adjunct treatment strategy to improve motor function in PD.


Assuntos
COVID-19/prevenção & controle , Doença de Parkinson/psicologia , Estresse Psicológico/complicações , Estudos de Casos e Controles , Progressão da Doença , Exercício Físico , Marcha , Humanos , Hipocinesia/etiologia , Nova Zelândia , Doença de Parkinson/complicações , Equilíbrio Postural , SARS-CoV-2 , Inquéritos e Questionários , Tremor/etiologia
9.
J Coll Physicians Surg Pak ; 30(7): 858-860, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34271793

RESUMO

Radical surgery to achieve optimal cytoreduction in locally advanced caecal cancer may dictate femoral or sciatic nerve resection, especially in cases with pelvic side-wall involvement. In such a situation, gait disturbance is inevitable. A 61-year male with a new-onset right leg limping due to locally advanced right colon carcinoma underwent cytoreductive surgery (CRS) with partial resection of right pelvic side- wall, and hyperthermic intraperitoneal chemotherapy (HIPEC). During the operation, we aimed to preserve both the sciatic and femoral nerves to prevent further deterioration of his right leg limping postoperatively. However, we did not compromise the principles of radical surgery and all tumoral implants around femoral vessels and nerves were removed. Completeness of cytoreduction score was zero (CC0). The resection of all macroscopic disease is the main goal of CRS, but as seen in our case with tumor-related walking difficulty, nerve-sparing CRS and HIPEC may prevent further deterioration of the situation. Key Words: Cytoreductive surgery, Hyperthermic intraperitoneal chemotherapy, Sciatic nerve, Femoral nerve, Caecal cancer.


Assuntos
Neoplasias do Ceco , Hipertermia Induzida , Neoplasias Peritoneais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Marcha , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Perna (Membro) , Masculino , Neoplasias Peritoneais/terapia , Taxa de Sobrevida
10.
Trials ; 22(1): 463, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281611

RESUMO

BACKGROUND: Protocols involving intensive practice have shown positive outcomes. Constraint induced movement therapy (CIT) appears to be one of the best options for better outcomes in upper limb rehabilitation, but we still have little data about lower extremity constraint-induced movement therapy (LE-CIT) and its effects on gait and balance. OBJECTIVE: To evaluate the effects of an LE-CIT protocol on gait functionality and balance in chronic hemiparetic patients following a stroke. METHODS: The study adopts a randomized, controlled, single-blinded study design. Forty-two patients, who suffered a stroke, who were in the chronic phase of recovery (>6 months), with gait disability (no community gait), and who were able to walk at least 10 m with or without the advice or support of 1 person, will be randomly allocated to 2 groups: the LE-CIT group or the control group (intensive conventional therapy). People will be excluded if they have speech deficits that render them unable to understand and/or answer properly to evaluation scales and exercises selected for the protocol and/or if they have suffered any clinical event between the screening and the beginning of the protocol. Outcome will be assessed at baseline (T0), immediately after the intervention (T1), and after 6 months (T2). The outcome measures chosen for this trial are as follows: 6-min walk test (6minWT), 10-m walk test (10mWT), timed up and go (TUG), 3-D gait analysis (3DGA), Mini Balance Evaluation Systems Test (Mini-BESTest), and as a secondary measure, Lower Extremity Motor Activity Log will be evaluated (LE-MAL). The participants in both groups will receive 15 consecutive days of daily exercise. The participants in the LE-CIT group will be submitted to this protocol 2.5 h/day for 15 consecutive days. It will include (1) intensive supervised training, (2) use of shaping as strategy for motor training, and (3) application of a transfer package (plus 30 min). The control group will receive conventional physiotherapy for 2.5 h/day over 15 consecutive days (the same period as the CIT intervention). Repeated measures analyses will be made to compare differences and define clinically relevant changes between groups. RESULTS: Data collection is currently on-going and results are expected in 2021. DISCUSSION: LE-CIT seems to be a good protocol for inclusion into stroke survivors' rehabilitation as it has all the components needed for positive results, as well as intensity and transference of gains to daily life activities. TRIAL REGISTRATION: www.ensaiosclinicos.gov.br RBR-467cv6 . Registered on 10 October 2017. "Effects of Lower Extremities - Constraint Induced Therapy on gait and balance function in chronic hemipretic post-stroke patients".


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Terapia por Exercício , Marcha , Humanos , Extremidade Inferior , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
11.
Sensors (Basel) ; 21(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34283073

RESUMO

The evolution of low power electronics and the availability of new smart materials are opening new frontiers to develop wearable systems for medical applications, lifestyle monitoring, and performance detection. This paper presents the development and realization of a novel smart insole for monitoring the plantar pressure distribution and gait parameters; indeed, it includes a piezoresistive sensing matrix based on a Velostat layer for transducing applied pressure into an electric signal. At first, an accurate and complete characterization of Velostat-based pressure sensors is reported as a function of sizes, support material, and pressure trend. The realization and testing of a low-cost and reliable piezoresistive sensing matrix based on a sandwich structure are discussed. This last is interfaced with a low power conditioning and processing section based on an Arduino Lilypad board and an analog multiplexer for acquiring the pressure data. The insole includes a 3-axis capacitive accelerometer for detecting the gait parameters (swing time and stance phase time) featuring the walking. A Bluetooth Low Energy (BLE) 5.0 module is included for transmitting in real-time the acquired data toward a PC, tablet or smartphone, for displaying and processing them using a custom Processing® application. Moreover, the smart insole is equipped with a piezoelectric harvesting section for scavenging energy from walking. The onfield tests indicate that for a walking speed higher than 1 ms-1, the device's power requirements (i.e., P¯=5.84 mW) was fulfilled. However, more than 9 days of autonomy are guaranteed by the integrated 380-mAh Lipo battery in the total absence of energy contributions from the harvesting section.


Assuntos
Análise da Marcha , Sapatos , Fontes de Energia Elétrica , Marcha , Caminhada
12.
Sensors (Basel) ; 21(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34283080

RESUMO

The application of artificial intelligence techniques to wearable sensor data may facilitate accurate analysis outside of controlled laboratory settings-the holy grail for gait clinicians and sports scientists looking to bridge the lab to field divide. Using these techniques, parameters that are difficult to directly measure in-the-wild, may be predicted using surrogate lower resolution inputs. One example is the prediction of joint kinematics and kinetics based on inputs from inertial measurement unit (IMU) sensors. Despite increased research, there is a paucity of information examining the most suitable artificial neural network (ANN) for predicting gait kinematics and kinetics from IMUs. This paper compares the performance of three commonly employed ANNs used to predict gait kinematics and kinetics: multilayer perceptron (MLP); long short-term memory (LSTM); and convolutional neural networks (CNN). Overall high correlations between ground truth and predicted kinematic and kinetic data were found across all investigated ANNs. However, the optimal ANN should be based on the prediction task and the intended use-case application. For the prediction of joint angles, CNNs appear favourable, however these ANNs do not show an advantage over an MLP network for the prediction of joint moments. If real-time joint angle and joint moment prediction is desirable an LSTM network should be utilised.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Fenômenos Biomecânicos , Marcha , Cinética
13.
Sensors (Basel) ; 21(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34283104

RESUMO

Functional electrical stimulation (FES) is a technique used in rehabilitation, allowing the recreation or facilitation of a movement or function, by electrically inducing the activation of targeted muscles. FES during cycling often uses activation patterns which are based on the crank angle of the pedals. Dynamic changes in their underlying predefined geometrical models (e.g., change in seating position) can lead to desynchronised contractions. Adaptive algorithms with a real-time interpretation of anatomical segments can avoid this and open new possibilities for the automatic design of stimulation patterns. However, their ability to accurately and precisely detect stimulation triggering events has to be evaluated in order to ensure their adaptability to real-case applications in various conditions. In this study, three algorithms (Hilbert, BSgonio, and Gait Cycle Index (GCI) Observer) were evaluated on passive cycling inertial data of six participants with spinal cord injury (SCI). For standardised comparison, a linear phase reference baseline was used to define target events (i.e., 10%, 40%, 60%, and 90% of the cycle's progress). Limits of agreement (LoA) of ±10% of the cycle's duration and Lin's concordance correlation coefficient (CCC) were used to evaluate the accuracy and precision of the algorithm's event detections. The delays in the detection were determined for each algorithm over 780 events. Analysis showed that the Hilbert and BSgonio algorithms validated the selected criteria (LoA: +5.17/-6.34% and +2.25/-2.51%, respectively), while the GCI Observer did not (LoA: +8.59/-27.89%). When evaluating control algorithms, it is paramount to define appropriate criteria in the context of the targeted practical application. To this end, normalising delays in event detection to the cycle's duration enables the use of a criterion that stays invariable to changes in cadence. Lin's CCC, comparing both linear correlation and strength of agreement between methods, also provides a reliable way of confirming comparisons between new control methods and an existing reference.


Assuntos
Terapia por Estimulação Elétrica , Traumatismos da Medula Espinal , Algoritmos , Estimulação Elétrica , Marcha , Humanos
14.
Sensors (Basel) ; 21(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34283149

RESUMO

Implicit authentication mechanisms are expected to prevent security and privacy threats for mobile devices using behavior modeling. However, recently, researchers have demonstrated that the performance of behavioral biometrics is insufficiently accurate. Furthermore, the unique characteristics of mobile devices, such as limited storage and energy, make it subject to constrained capacity of data collection and processing. In this paper, we propose an implicit authentication architecture based on edge computing, coined Edge computing-based mobile Device Implicit Authentication (EDIA), which exploits edge-based gait biometric identification using a deep learning model to authenticate users. The gait data captured by a device's accelerometer and gyroscope sensors is utilized as the input of our optimized model, which consists of a CNN and a LSTM in tandem. Especially, we deal with extracting the features of gait signal in a two-dimensional domain through converting the original signal into an image, and then input it into our network. In addition, to reduce computation overhead of mobile devices, the model for implicit authentication is generated on the cloud server, and the user authentication process also takes place on the edge devices. We evaluate the performance of EDIA under different scenarios where the results show that i) we achieve a true positive rate of 97.77% and also a 2% false positive rate; and ii) EDIA still reaches high accuracy with limited dataset size.


Assuntos
Identificação Biométrica , Aprendizado Profundo , Computadores de Mão , Marcha , Privacidade
15.
Bone Joint J ; 103-B(7 Supple B): 9-16, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34192921

RESUMO

AIMS: The aims of this study were to develop an in vivo model of periprosthetic joint infection (PJI) in cemented hip hemiarthroplasty, and to monitor infection and biofilm formation in real-time. METHODS: Sprague-Dawley rats underwent cemented hip hemiarthroplasty via the posterior approach with pre- and postoperative gait assessments. Infection with Staphylococcus aureus Xen36 was monitored with in vivo photoluminescent imaging in real-time. Pre- and postoperative gait analyses were performed and compared. Postmortem micro (m) CT was used to assess implant integration; field emission scanning electron microscopy (FE-SEM) was used to assess biofilm formation on prosthetic surfaces. RESULTS: All animals tolerated surgery well, with preservation of gait mechanics and weightbearing in control individuals. Postoperative in vivo imaging demonstrated predictable evolution of infection with logarithmic signal decay coinciding with abscess formation. Postmortem mCT qualitative volumetric analysis showed high contact area and both cement-bone and cement-implant interdigitation. FE-SEM revealed biofilm formation on the prosthetic head. CONCLUSION: This study demonstrates the utility of a new, high-fidelity model of in vivo PJI using cemented hip hemiarthroplasty in rats. Inoculation with bioluminescent bacteria allows for non-invasive, real-time monitoring of infection. Cite this article: Bone Joint J 2021;103-B(7 Supple B):9-16.


Assuntos
Hemiartroplastia , Prótese de Quadril , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/microbiologia , Animais , Distinções e Prêmios , Biofilmes , Cimentos Ósseos , Modelos Animais de Doenças , Marcha , Masculino , Microscopia Eletrônica de Varredura , Impressão Tridimensional , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
16.
Artigo em Inglês | MEDLINE | ID: mdl-34203676

RESUMO

Gait impairment often limits physical activity and negatively impacts quality of life. EMG-Biofeedback (EMG-BFB), one of the more effective interventions for improving gait impairment, has been limited to laboratory use due to system costs and technical requirements, and has therefore not been tested on a larger scale. In our research, we aimed to develop and validate a cost-effective, commercially available EMG-BFB device for home- and community-based use. We began by repurposing mTrigger® (mTrigger LLC, Newark, DE, USA), a cost-effective, portable EMG-BFB device, for gait application. This included developing features in the cellphone app such as step feedback, success rate, muscle activity calibration, and cloud integration. Next, we tested the validity and reliability of the mTrigger device in healthy adults by comparing it to a laboratory-grade EMG system. While wearing both devices, 32 adults walked overground and on a treadmill at four speeds (0.3, 0.6, 0.9, and 1.2 m/s). Statistical analysis revealed good to excellent test-retest reliability (r > 0.89) and good to excellent agreement in the detection of steps (ICC > 0.85) at all speeds between two systems for treadmill walking. Our results indicated that mTrigger compared favorably to a laboratory-grade EMG system in the ability to assess muscular activity and to provide biofeedback during walking in healthy adults.


Assuntos
Marcha , Qualidade de Vida , Adulto , Biorretroalimentação Psicológica , Humanos , Reprodutibilidade dos Testes , Caminhada
17.
Medicina (Kaunas) ; 57(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206943

RESUMO

Background and Objectives: Acquiring knowledge about the magnitude and direction of induced joint forces during modifying gait strategies is critical for proper exercise prescription. The present study aimed to evaluate whether a heel-first strike pattern during gait can affect the biomechanical characteristics of ankle and knee joints among asymptomatic people. Materials and Methods: In this cross-sectional study performed in the biomechanics laboratory, 13 professional healthy male athletes walked on an instrumented walkway under two walking conditions. For the normal condition, subjects were instructed to walk as they normally would. For the heel-first strike condition, subjects were instructed to walk with heel-first strike pattern and increase heel contact duration as much as possible. Then, knee and ankle joint range of motions and moments, as well as vertical ground reaction force was measured by the Kistler force plate and Vicon motion analysis system. Results: Knee flexion angle at the initial contact and during stance phase was significantly lower when increasing the heel strike pattern. In addition, the mean values of the knee external rotation and adductor moments during heel strike condition were lower than those in normal walking. Further, the ankle dorsiflexion range of motion (ROM) during mid-stance increased significantly during heel-first strike pattern compared to the value in normal gait pattern. Conclusions: The modification of gait pattern including heel-first strike pattern can reduce the mechanical load applied to the knee, while improving the extensibility of gastro-soleus muscle complex.


Assuntos
Articulação do Tornozelo , Tornozelo , Fenômenos Biomecânicos , Estudos Transversais , Marcha , Calcanhar , Humanos , Articulação do Joelho , Masculino
18.
Biosensors (Basel) ; 11(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208947

RESUMO

Wearable robotic devices have been proved to considerably reduce the energy expenditure of human walking. It is not only suitable for healthy people, but also for some patients who require rehabilitation exercises. However, in many cases, the weight of soft exosuits are relatively large, which makes it difficult for the assistant effect of the system to offset the metabolic consumption caused by the extra weight, and the heavy weight will make people uncomfortable. Therefore, reducing the weight of the whole system as much as possible and keeping the soft exosuit output power unchanged, may improve the comfort of users and further reduce the metabolic consumption. In this paper, we show that a novel lightweight soft exosuit which is currently the lightest among all known powered exoskeletons, which assists hip flexion. Indicated from the result of experiment, the novel lightweight soft exosuit reduces the metabolic consumption rate of wearers when walking on the treadmill at 5 km per hour by 11.52% compared with locomotion without the exosuit. Additionally, it can reduce more metabolic consumption than the hip extension assisted (HEA) and hip flexion assisted (HFA) soft exosuit which our team designed previously, which has a large weight. The muscle fatigue experiments show that using the lightweight soft exosuit can also reduce muscle fatigue by about 10.7%, 40.5% and 5.9% for rectus femoris, vastus lateralis and gastrocnemius respectively compared with locomotion without the exosuit. It is demonstrated that decreasing the weight of soft exosuit while maintaining the output almost unchanged can further reduce metabolic consumption and muscle fatigue, and appropriately improve the users' comfort.


Assuntos
Exoesqueleto Energizado , Fenômenos Biomecânicos , Metabolismo Energético , Terapia por Exercício , Marcha/fisiologia , Humanos , Fadiga Muscular/fisiologia , Robótica/instrumentação , Caminhada/fisiologia , Dispositivos Eletrônicos Vestíveis
19.
Trials ; 22(1): 477, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294137

RESUMO

BACKGROUND: The control of the dynamic functional leg alignment (dFLA) and biomechanical load are important joint-related aspects regarding the development of osteoarthritis (OA). Research on level walking with feedback on load-related parameters has provided innovative treatment possibilities. With regard to walking on sloped surfaces, fundamental biomechanical knowledge exists. However, comprehensive data on the agreement of kinematics and kinetics of self-paced ramp versus sloped treadmill walking is lacking. Further, deeper insights into the control of the dFLA during decline walking and the usefulness of real-time feedback are missing. METHODS/DESIGN: Thirty healthy participants aged between 18 and 35 years will be included. They will complete a three-dimensional gait analysis walking self-paced up and down on a 5-m ramp with a 10° inclination. Subsequently, speed-matched to ramp-up walking and self-paced 10° incline split-belt treadmill walking will be assessed. Afterwards, the participants will be observed under four different conditions of 10° declined walking on the same treadmill (a) self-paced walking, (b) self-paced walking with an internal focus of attention, (c) self-paced walking with real-time feedback, and (d) condition c speed-matched walking. The primary outcome parameter will be the frontal knee range of motion (fKROM). Secondary outcomes include the ground reaction force loading rate, spatial-temporal parameters, as well as sagittal, frontal and transversal kinematics, and kinetics for the lower extremities. DISCUSSION: The findings aim at improving the understanding of the effects of real-time feedback on the control of the dFLA and lower limb loading. Following clinical practicable methods for effective feedback devices can be developed and evaluated. Additionally, the first dataset comparing kinematic and kinetic parameters for decline and incline ramp walking versus walking on an instrumented treadmill will be available for appropriate intervention planning. TRIAL REGISTRATION: ClinicalTrials.gov NCT04763850 . Prospectively registered on 21 February 2021.


Assuntos
Marcha , Caminhada , Adolescente , Adulto , Fenômenos Biomecânicos , Teste de Esforço , Retroalimentação , Humanos , Cinética , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
20.
Sensors (Basel) ; 21(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34300399

RESUMO

Loss-of-balance (LOB) events, such as trips and slips, are frequent among community-dwelling older adults and are an indicator of increased fall risk. In a preliminary study, eight community-dwelling older adults with a history of falls were asked to perform everyday tasks in the real world while donning a set of three inertial measurement sensors (IMUs) and report LOB events via a voice-recording device. Over 290 h of real-world kinematic data were collected and used to build and evaluate classification models to detect the occurrence of LOB events. Spatiotemporal gait metrics were calculated, and time stamps for when LOB events occurred were identified. Using these data and machine learning approaches, we built classifiers to detect LOB events. Through a leave-one-participant-out validation scheme, performance was assessed in terms of the area under the receiver operating characteristic curve (AUROC) and the area under the precision recall curve (AUPR). The best model achieved an AUROC ≥0.87 for every held-out participant and an AUPR 4-20 times the incidence rate of LOB events. Such models could be used to filter large datasets prior to manual classification by a trained healthcare provider. In this context, the models filtered out at least 65.7% of the data, while detecting ≥87.0% of events on average. Based on the demonstrated discriminative ability to separate LOBs and normal walking segments, such models could be applied retrospectively to track the occurrence of LOBs over an extended period of time.


Assuntos
Acidentes por Quedas , Dispositivos Eletrônicos Vestíveis , Acidentes por Quedas/prevenção & controle , Idoso , Marcha , Humanos , Estudos Retrospectivos , Caminhada
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