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1.
J Biomech Eng ; 145(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36082472

RESUMO

Musculoskeletal modeling and simulation have been an emerging trend in human gait analysis. It allows the user to isolate certain biomechanical conditions and elucidate the dynamics of joints and muscles. This study used an open-source musculoskeletal modeling and simulation tool, opensim to investigate the biomechanical effect of knee brace. It collected gait data from thirty-eight participants and examined the gait spatio-temporal parameters, joint angles, and joint moments. Static optimization was performed to estimate the lower extremity muscle force. Statistical analysis was conducted to identify the difference between normal and braced gaits. The results demonstrated the feasibility of this method to investigate the interaction and coordination of lower extremity joints and muscles. The knee brace constrained the range of the motion of the knee during walking. It also changed the walking speed, step length, and stance-to-swing ratio. Several significant differences were found in the joint moments and muscle forces of the rectus femoris, gastrocnemius, soleus and tibialis anterior. Musculoskeletal modeling and simulation tool offers a less invasive and practical alternative to analyze human motion. It also provides a means to investigate the effect of medical devices such as knee brace, which can be potentially beneficial for the future design and development of such devices and for the derivation of future rehabilitation treatment to improve patient's gait.


Assuntos
Marcha , Caminhada , Fenômenos Biomecânicos , Braquetes , Marcha/fisiologia , Humanos , Articulação do Joelho/fisiologia , Músculo Esquelético/fisiologia , Caminhada/fisiologia
2.
Appl Ergon ; 106: 103879, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36058167

RESUMO

The objective of this study was to quantify performance in an obstacle clearance task among individuals with excess body weight or body mass index (BMI). Task performance was operationalized as the maximum obstacle height cleared, four duration measures of successful task completion and compensatory movements used in the process of task completion. Eighteen participants with a BMI exceeding 30 kg/m2 completed a laboratory experiment that required stepping over seven lightweight obstacles. Obstacle heights were sequentially increased from 36 cm in 5 cm increments until participants were unsuccessful or unable to clear the obstacle up to 66 cm. Successful task completions decreased from 100% at an obstacle height of 36 cm to 66.1% at 66 cm. Higher obstacle heights were associated with significantly fewer task completions, longer leading and trailing leg stance and overall task duration, and more frequent use of compensatory movements for successful obstacle clearance. Cox PH regression was used to test the association between probability of obstacle clearance and normalized obstacle height adjusting for BMI, standing balance, and type of compensatory movement used, namely, hover and pivot motions involving the leg, and hands for bracing. The probability of successful task completion significantly decreased with increases in BMI (hazard ratio, HR = 1.14, 95% CI: 1.05-1.25), and increased with use of a leg pivot motion (HR = 0.30, 95% CI: 0.09-0.96) during task completion, after adjusting for standing balance and other types of compensatory movements. Overall, the results demonstrated that obstacle clearance performance is affected by an individual's BMI and the use of compensatory behaviors for regaining stability. The ability to recruit internal and external stabilization techniques could potentially serve as a clinical indicator of reduced fall risk and be the focus of fall prevention interventions. Implications for evaluating stability, fall risk, and identifying modifiable factors for fall prevention in the obese population are discussed.


Assuntos
Marcha , Equilíbrio Postural , Humanos , Índice de Massa Corporal , Cinética , Movimento
3.
Arch Gerontol Geriatr ; 104: 104827, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36191493

RESUMO

BACKGROUND/OBJECTIVE: Diabetes mellitus (DM) is associated with walking performance, but potential underlying mechanisms of this association remain unclear. The present study aims to disentangle the pathways linking DM to gait and falls through the serial mediation effect of vision and cognition among the older population. METHODS: Data were taken from wave 9 (2018-2019) of the English Longitudinal Study of Aging (ELSA), including 5496 participants aged 60 years and older. DM was identified based on medical diagnosis and laboratory tests. Vision and falls were self-reported. Cognition was evaluated using questionnaire. Gait speed was measured by the "timed walking test". Serial mediation analysis was performed using Mplus 8.3. RESULTS: DM was associated with impaired gait speed (c = 0.085, P < 0.05) and falls (c = 0.061, P < 0.05). The serial mediation model revealed that vision and cognition significantly mediated the association of DM with impaired gait speed, with 17.97% and 23.60% of the total effects explained by vision and cognition respectively, and 3.37% explained by the path through vision and then cognition. Similarly, vision and cognition significantly mediated the association of DM with falls, with 14.99% and 6.67% of the total effects explained by vision and cognition respectively, and 1.67% explained by the path through vision and then cognition. CONCLUSIONS: These findings contribute to deeper understanding of the mechanism underlying the association of DM with walking performance. Evaluation and intervention targeted at vision and the cognition may be beneficial for improving gait or reducing falls in older adults with DM.


Assuntos
Acidentes por Quedas , Diabetes Mellitus , Humanos , Pessoa de Meia-Idade , Idoso , Vida Independente , Estudos Longitudinais , Marcha , Cognição , Velocidade de Caminhada , Diabetes Mellitus/epidemiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-36349610

RESUMO

AIM: Bipolar disorder (BD) patients show neurological abnormalities in form of neurological and cerebellar soft signs (NSS and CSS). NSS represents heterogeneous group of symptoms representing i.a. deficits of motor coordination, sequencing of complex motor acts and sensory integration. CSS were introduced as group of the neurological deficits of posture, gait, kinetic functions, eye movements and speech, associated more specifically to cerebellar abnormalities than NSS. Studies show significant effect size variability of those symptoms in BD group suggesting the existence of differing subpopulations. The aim of our study was to evaluate the effect of BD type, stage and the history of psychotic symptoms (HoPS) on the severity of CSS and NSS as none of the previous studies had verified the role of those categories. METHODS: This study involved 181 participants: 116 euthymic BD patients (66 BD I, 50 BD II) and 65 healthy controls (HC). CSS was assessed with the International Cooperative Ataxia Rating Scale and NSS with Neurological Evaluation Scale. Patients were divided into early and late stage of the disorder according to Kapczinski's criteria. Rater was blind to patients' stage, type and HoPS. RESULTS: Staging was related to vast majority of CSS and NSS scores. HoPS was related to oculomotor deficits. The effect of BD type was the least significant. Late stage BD showed more severe CSS and NSS than HC in every measure. There were no differences between early stage BD and HC, apart of posture and gait disturbances. Except of sensory integration scores, late stage BD showed higher CSS and NSS rates than early stage patients. CONCLUSION: In this hitherto the largest study of neurological abnormalities in BD we have shown significant role of staging in CSS and NSS severity. Progression criteria based on inter-episode psychosocial functioning may stand as unrecognised factor responsible for variability observed in previous studies evaluating neurological abnormalities in BD. Our study suggests that in clinical practice NSS and CSS may be potentially used as easy-to-assess biological marker of BD staging. Observed severity of neurological impairments of BD patients may more likely correspond to the disease progression than to BD type and HoPS.


Assuntos
Transtorno Bipolar , Humanos , Transtorno Ciclotímico , Cerebelo , Movimentos Oculares , Marcha
5.
J Biomech Eng ; 145(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36149020

RESUMO

Active prostheses can provide net positive work to individuals with amputation, offering more versatility across locomotion tasks than passive prostheses. However, the effect of powered joints on bilateral biomechanics has not been widely explored for ambulation modes different than level ground and treadmill walking. In this study, we present the bilateral biomechanics of stair ascent and descent with a powered knee-ankle prosthesis compared to the biomechanical profiles of able-bodied subjects at different configurations of stair height between 102 mm and 178 mm. In addition, we include reference profiles from users with passive prostheses for the nominal stair height of 152 mm to place our findings in relation to the typical solution for individuals with transfemoral amputation (TFA). We report the biomechanical profiles of kinematics, kinetics, and power, together with temporal and waveform symmetry and distribution of mechanical energy across the joints. We found that an active prosthesis provides a substantial contribution to mechanical power during stair ascent and power absorption during stair descent and gait patterns like able-bodied subjects. The active prosthesis enables step-over-step gait in stair ascent. This translates into a lower mechanical energy requirement on the intact side, with a 57% reduction of energy at the knee and 26% at the hip with respect to the passive prosthesis. For stair descent, we found a 28% reduction in the negative work done by the intact ankle. These results reflect the benefit of active prostheses, allowing the users to complete tasks more efficiently than passive legs. However, in comparison to able-bodied biomechanics, the results still differ from the ideal patterns. We discuss the limitations that explain this difference and suggest future directions for the design of impedance controllers by taking inspiration from the biological modulation of the knee moment as a function of the stair height.


Assuntos
Membros Artificiais , Fenômenos Biomecânicos , Impedância Elétrica , Marcha , Humanos , Articulação do Joelho , Caminhada
6.
Turk J Med Sci ; 52(3): 658-666, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36326313

RESUMO

BACKGROUND: Cerebral Palsy (CP) is the most frequent cause of physical disability in childhood. CP causes primary deficits such as impairments in muscle tone, muscle weakness, problems in selective motor control and secondary deficits such as contractures and deformities. These deficits lead to motor disorders during movement causing limitations in gait. Sixty percent of children with CP can walk independently despite these problems, however, they present with various gait abnormalities. Gait analysis is used in the quantitative assessment of gait disturbances providing functional diagnosis, assessment for treatment, planning, and monitoring of progress. G-Walk is a wearable sensor device which provides quantitative gait analysis via spatiotemporal parameters and pelvic girdle angles. In literature, there is no study investigating the reliability of the G-Walk in children with CP. The purpose of this study was to confirm the test-retest reliability of a commercially available body-worn sensor 'BTS G-WALK sensor system' for spatiotemporal gait parameters in children with CP. METHODS: Fifty-four children with CP (mean age: 9.19 ± 3.49 years), Gross Motor Function Classification System (GMFCS) level I-II completed the test-retest protocol with 5 days between tests. The test-retest reliability was calculated using intra-class correlation coefficients (ICC). Minimal detectable changes were calculated using standard error measurements. RESULTS: According to the analysis, ICC varied from 0.799 to 0.977 in all of the gait parameters. The statistical analysis showed that all G-Walk parameters' measurements were found to have almost perfect test-retest reliability. DISCUSSION: The G-Walk was found to be reliable in gait parameters for children with CP between ages 5 and 15, in GMFCS level I-II. A gait analysis carried out with the G-Walk system is a reliable method to assess gait in children with CP in a clinical setting.


Assuntos
Paralisia Cerebral , Dispositivos Eletrônicos Vestíveis , Criança , Humanos , Pré-Escolar , Adolescente , Paralisia Cerebral/diagnóstico , Reprodutibilidade dos Testes , Análise da Marcha , Marcha/fisiologia
7.
Sci Rep ; 12(1): 18773, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335154

RESUMO

Alcohol contributes to a large number of diseases and health conditions related to injuries. The aim of our study was to evaluate gender differences in forward and backward gait when sober and at a breath alcohol concentration (BrAC) of 0.11%. Fifty females and fifty males participated in our study. The gait analysis was performed twice, when sober and after drinking a given amount of vodka mixed with orange juice. Under both conditions, participants were asked to walk forward and then backward on a Zebris platform. Multivariate analysis and the Mann-Whitney U test were used to compare the differences between genders when walking forward and backward. The Wilcoxon Signed Ranks test was used to compare the differences between 0.00% BrAC and 0.11% BrAC. Spearman's Rho was used to analyze the relationship between the AUDIT score, anthropometrical characteristics and the subjective score of drunkenness and gait parameters. The results show different strategies to improve stability during gait in women and men when intoxicated with alcohol. When intoxicated, males in forward gait increase their stability by increasing their foot rotation, while females increase their step width. A decrease in balance-related variables was observed in females when walking backward with a BrAC of 0.11%. Additionally, females tended to perform an increase in balance-related gait variables when subjectively feeling more drunk in both forward and backward gait. Different strategies to maintain stability during gait were observed in women and men. The results of our study show that alcohol intoxication has a greater impact on gait in females who tended to perform an increase in balance-related variables with an increase in their subjective score of drunkenness.


Assuntos
Intoxicação Alcoólica , Feminino , Humanos , Masculino , Fatores Sexuais , Marcha , Testes Respiratórios/métodos , Caminhada , Etanol
8.
BMC Nephrol ; 23(1): 350, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319951

RESUMO

BACKGROUND: Muscle dysfunction is prevalent in dialysis patients. Gait speed and handgrip strength are simple and reliable methods of assessing muscle function. Numerous observational studies have linked 25-hydroxy vitamin D[25(OH)D] status with gait speed and handgrip strength in populations without kidney diseases. This study aimed to evaluate the potential associations of 25(OH)D status with gait speed and handgrip strength in patients on hemodialysis. METHODS: In this observational cross-sectional study, demographic data, biological data, and dialysis parameters were collected. Gait speed and handgrip strength were measured. Multiple linear regression and logistic regression analysis were used to investigate the relationship of 25(OH)D status with gait speed and handgrip strength after adjusting for potential confounders. RESULTS: Overall, a total of 118 participants undergoing hemodialysis were included. Seventy-one (60.2%) participants were male. The median 25(OH)D status in participants was 11.58 (interquartile range: 8.51 to 15.41) ng/ml. When controlling for age, gender, dialysis vintage, and other confounders with a p-value < 0.15 in univariate analyses, 25(OH)D was significantly positively associated with gait speed (ß = 0.16, 95% CI 0.05 to 0.28, p = 0.006) and handgrip strength (ß = 3.83, 95% CI 1.09 to 6.56, p = 0.007). CONCLUSION: Our study showed that 25(OH)D status seemed to be associated with gait speed and handgrip strength in patients on hemodialysis. However, these results were not robust. The relationships between 25(OH)D status and gait speed and handgrip should be further explored.


Assuntos
Força da Mão , Velocidade de Caminhada , Humanos , Masculino , Feminino , Força da Mão/fisiologia , Velocidade de Caminhada/fisiologia , Diálise Renal , Vitamina D , Marcha/fisiologia
9.
Sci Rep ; 12(1): 18347, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319838

RESUMO

Load carriage is an inevitable daily task for soldiers. The purposes of this study were to explore the extent to which gait variability (GV) is affected by load carriage and experience among military cadets, and whether experience-related differences in GV are dependent on task demand. Two groups of cadets (30 experienced, 30 less experienced) completed a load carriage task in each of three load conditions (no load, 16 kg, 32 kg). Three categories of GV measures were obtained: spatiotemporal variability, joint kinematic variability, and Lyapunov exponents. Compared to traditional mean gait measures, GV measures were more discriminative of experience: although both groups showed similar mean gait measures, the experienced participants had reduced variability in spatiotemporal measures (p ≤ 0.008) and joint kinematics (p ≤ 0.004), as well as lower levels of long-term local dynamic stability at the ankle (p = 0.040). In both groups, heavier loads were also caused increased GV (p ≤ 0.018) and enhanced short-term local dynamic stability at the knee (p = 0.014). These results emphasize the importance of GV measures, which may provide a more complete description of adaptability, stability, and control; highlight alternate movement strategies during more difficult load carriage; and capture experience-related differences in load carriage strategies.


Assuntos
Militares , Humanos , Suporte de Carga , Marcha , Fenômenos Biomecânicos , Articulação do Tornozelo , Caminhada
10.
Sensors (Basel) ; 22(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36365868

RESUMO

Motion capture is the current gold standard for assessing movement of the human body, but laboratory settings do not always mimic the natural terrains and movements encountered by humans. To overcome such limitations, a smart sock that is equipped with stretch sensors is being developed to record movement data outside of the laboratory. For the smart sock stretch sensors to provide valuable feedback, the sensors should have durability of both materials and signal. To test the durability of the stretch sensors, the sensors were exposed to high-cycle fatigue testing with simultaneous capture of the capacitance. Following randomization, either the fatigued sensor or an unfatigued sensor was placed in the plantarflexion position on the smart sock, and participants were asked to complete the following static movements: dorsiflexion, inversion, eversion, and plantarflexion. Participants were then asked to complete gait trials. The sensor was then exchanged for either an unfatigued or fatigued plantarflexion sensor, depending upon which sensor the trials began with, and each trial was repeated by the participant using the opposite sensor. Results of the tests show that for both the static and dynamic movements, the capacitive output of the fatigued sensor was consistently higher than that of the unfatigued sensor suggesting that an upwards drift of the capacitance was occurring in the fatigued sensors. More research is needed to determine whether stretch sensors should be pre-stretched prior to data collection, and to also determine whether the drift stabilizes once the cyclic softening of the materials comprising the sensor has stabilized.


Assuntos
Tornozelo , Movimento , Humanos , Articulação do Tornozelo , Movimento (Física) , Marcha , Fenômenos Biomecânicos
11.
Sensors (Basel) ; 22(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36365930

RESUMO

Elderly gait is a source of rich information about their physical and mental health condition. As an alternative to the multiple sensors on the lower body parts, a single sensor on the pelvis has a positional advantage and an abundance of information acquirable. This study aimed to improve the accuracy of gait event detection in the elderly using a single sensor on the waist and deep learning models. Data were gathered from elderly subjects equipped with three IMU sensors while they walked. The input taken only from the waist sensor was used to train 16 deep-learning models including a CNN, RNN, and CNN-RNN hybrid with or without the Bidirectional and Attention mechanism. The groundtruth was extracted from foot IMU sensors. A fairly high accuracy of 99.73% and 93.89% was achieved by the CNN-BiGRU-Att model at the tolerance window of ±6 TS (±6 ms) and ±1 TS (±1 ms), respectively. Advancing from the previous studies exploring gait event detection, the model demonstrated a great improvement in terms of its prediction error having an MAE of 6.239 ms and 5.24 ms for HS and TO events, respectively, at the tolerance window of ±1 TS. The results demonstrated that the use of CNN-RNN hybrid models with Attention and Bidirectional mechanisms is promising for accurate gait event detection using a single waist sensor. The study can contribute to reducing the burden of gait detection and increase its applicability in future wearable devices that can be used for remote health monitoring (RHM) or diagnosis based thereon.


Assuntos
Aprendizado Profundo , Dispositivos Eletrônicos Vestíveis , Humanos , Idoso , Algoritmos , Marcha ,
12.
Sensors (Basel) ; 22(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36366049

RESUMO

Recently, radio frequency identification (RFID) sensing has attracted much attention due to its contact-free nature, low cost, light weight and other advantages. RFID-based person detection has also become a hot research topic, but there are still some problems in the existing research. First, most of the current studies cannot identify numerous people at a time well. Second, in order to detect more accurately, it is necessary to evaluate the whole-body activity of a person, which will consume a lot of time to process the data and cannot be applied in time. To solve these problems, in this paper we propose RF-Detection, a person detection system using RFID. First of all, RF-Detection takes step length as the standard for person detection, divides step length into specific sections according to the relationship between step length and height, and achieves high accuracy for new user detection through a large amount of training for a specific step length. Secondly, RF-Detection can better identify the number of people in the same space by segmenting continuous people. Finally, the data collection was reduced by expanding the data set, and the deep learning method was used to further improve the accuracy. The results show that the overall recognition accuracy of RF-Detection is 98.93%.


Assuntos
Dispositivo de Identificação por Radiofrequência , Humanos , Dispositivo de Identificação por Radiofrequência/métodos , Marcha
13.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366088

RESUMO

The aim of this study was to objectively assess and compare gait capacity and gait performance in rehabilitation inpatients with stroke or incomplete spinal cord injury (iSCI) using inertial measurement units (IMUs). We investigated how gait capacity (what someone can do) is related to gait performance (what someone does). Twenty-two inpatients (11 strokes, 11 iSCI) wore ankle positioned IMUs during the daytime to assess gait. Participants completed two circuits to assess gait capacity. These were videotaped to certify the validity of the IMU algorithm. Regression analyses were used to investigate if gait capacity was associated with gait performance (i.e., walking activity and spontaneous gait characteristics beyond therapy time). The ankle positioned IMUs validly assessed the number of steps, walking time, gait speed, and stride length (r ≥ 0.81). The walking activity was strongly (r ≥ 0.76) related to capacity-based gait speed. Maximum spontaneous gait speed and stride length were similar to gait capacity. However, the average spontaneous gait speed was half the capacity-based gait speed. Gait capacity can validly be assessed using IMUs and is strongly related to gait performance in rehabilitation inpatients with neurological disorders. Measuring gait performance with IMUs provides valuable additional information about walking activity and spontaneous gait characteristics to inform about functional recovery.


Assuntos
Pacientes Internados , Traumatismos da Medula Espinal , Humanos , Marcha , Caminhada , Traumatismos da Medula Espinal/reabilitação , Tecnologia
14.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366096

RESUMO

Inertial measurement units (IMUs) offer an attractive way to study human lower-limb kinematics without traditional laboratory constraints. We present an error-state Kalman filter method to estimate 3D joint angles, joint angle ranges of motion, stride length, and step width using data from an array of seven body-worn IMUs. Importantly, this paper contributes a novel joint axis measurement correction that reduces joint angle drift errors without assumptions of strict hinge-like joint behaviors of the hip and knee. We evaluate the method compared to two optical motion capture methods on twenty human subjects performing six different types of walking gait consisting of forward walking (at three speeds), backward walking, and lateral walking (left and right). For all gaits, RMS differences in joint angle estimates generally remain below 5 degrees for all three ankle joint angles and for flexion/extension and abduction/adduction of the hips and knees when compared to estimates from reflective markers on the IMUs. Additionally, mean RMS differences in estimated stride length and step width remain below 0.13 m for all gait types, except stride length during slow walking. This study confirms the method's potential for non-laboratory based gait analysis, motivating further evaluation with IMU-only measurements and pathological gaits.


Assuntos
Marcha , Caminhada , Humanos , Fenômenos Biomecânicos , Extremidade Inferior , Articulação do Tornozelo , Articulação do Joelho
15.
Sensors (Basel) ; 22(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366139

RESUMO

Achieving a normal gait trajectory for an amputee's active prosthesis is challenging due to its kinematic complexity. Accordingly, lower limb gait trajectory kinematics and gait phase segmentation are essential parameters in controlling an active prosthesis. Recently, the most practiced algorithm in gait trajectory generation is the neural network. Deploying such a complex Artificial Neural Network (ANN) algorithm on an embedded system requires performing the calculations on an external computational device; however, this approach lacks mobility and reliability. In this paper, more simple and reliable ANNs are investigated to be deployed on a single low-cost Microcontroller (MC) and hence provide system mobility. Two neural network configurations were studied: Multi-Layered Perceptron (MLP) and Convolutional Neural Network (CNN); the models were trained on shank and foot IMU data. The data were collected from four subjects and tested on a fifth to predict the trajectory of 200 ms ahead. The prediction was made for two cases: with and without providing the current phase of the gait. Then, the models were deployed on a low-cost microcontroller (ESP32). It was found that with fewer data (excluding the current gait phase), CNN achieved a better correlation coefficient of 0.973 when compared to 0.945 for MLP; when including the current phase, both network configurations achieved better correlation coefficients of nearly 0.98. However, when comparing the execution time required for the prediction on the intended MC, MLP was much faster than CNN, with an execution time of 2.4 ms and 142 ms, respectively. In summary, it was found that when training data are scarce, CNN is more efficient within the acceptable execution time, while MLP achieves relative accuracy with low execution time with enough data.


Assuntos
Aprendizado Profundo , Humanos , Reprodutibilidade dos Testes , Marcha , Redes Neurais de Computação , Algoritmos
16.
Sensors (Basel) ; 22(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366149

RESUMO

We propose a framework for optimizing personalized treatment outcomes for patients with neurological diseases. A typical consequence of such diseases is gait disorders, partially explained by command and muscle tone problems associated with spasticity. Intramuscular injection of botulinum toxin type A is a common treatment for spasticity. According to the patient's profile, offering the optimal treatment combined with the highest possible benefit-risk ratio is important. For the prediction of knee and ankle kinematics after botulinum toxin type A (BTX-A) treatment, we propose: (1) a regression strategy based on a multi-task architecture composed of LSTM models; (2) to introduce medical treatment data (MTD) for context modeling; and (3) a gating mechanism to model treatment interaction more efficiently. The proposed models were compared with and without metadata describing treatments and with serial models. Multi-task learning (MTL) achieved the lowest root-mean-squared error (RMSE) (5.60°) for traumatic brain injury (TBI) patients on knee trajectories and the lowest RMSE (3.77°) for cerebral palsy (CP) patients on ankle trajectories, with only a difference of 5.60° between actual and predicted. Overall, the best RMSE ranged from 5.24° to 6.24° for the MTL models. To the best of our knowledge, this is the first time that MTL has been used for post-treatment gait trajectory prediction. The MTL models outperformed the serial models, particularly when introducing treatment metadata. The gating mechanism is efficient in modeling treatment interaction and improving trajectory prediction.


Assuntos
Toxinas Botulínicas Tipo A , Paralisia Cerebral , Fármacos Neuromusculares , Humanos , Toxinas Botulínicas Tipo A/uso terapêutico , Fármacos Neuromusculares/uso terapêutico , Espasticidade Muscular , Marcha , Paralisia Cerebral/reabilitação , Resultado do Tratamento
17.
Sensors (Basel) ; 22(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366159

RESUMO

Exploration of the seabed may be complex, and different parameters must be considered for a robotic system to achieve tasks in this environment, such as soil characteristics, seabed gait, and hydrodynamic force in this extreme environment. This paper presents a gait simulation of a quadrupedal robot used on a typical terrigenous sediment seabed, considering the mechanical properties of the type of soil, stiffness, and damping and friction coefficients, referenced with the specialized literature and applied in a computational multibody model with many experimental data in a specific underwater environment to avoi hydrodynamic effects. The requirements of the positions and torque in the robot's active joints are presented in accordance with a 5R mechanism for the leg and the natural pattern shown in the gait of a dog on the ground. These simulation results are helpful for the design of a testbed, with a leg prototype and its respective hardware and software architecture and a subsequent comparison with the real results.


Assuntos
Robótica , Cães , Animais , Fenômenos Biomecânicos , Marcha , Torque , Solo
18.
Sensors (Basel) ; 22(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36366237

RESUMO

Researchers have made advances in reducing the metabolic rate of both walking and running by modulating mono-articular energy with exoskeletons. However, how to modulate multiarticular energy with exoskeletons to improve the energy economy of both walking and running is still a challenging problem, due to the lack of understanding of energy transfer among human lower-limb joints. Based on the study of the energy recycling and energy transfer function of biarticular muscles, we proposed a hip-knee unpowered exoskeleton that emulates and reinforces the function of the hamstrings and rectus femoris in different gait phases. The biarticular exo-tendon of the exoskeleton assists hamstrings to recycle the kinetic energy of the leg swing while providing hip extension torque in the swing phase. In the following stance phase, the exo-tendon releases the stored energy to assist the co-contraction of gluteus maximus and rectus femoris for both hip extension and knee extension, thus realizing the phased modulation of hip and knee joint energy. The metabolic rate of both walking (1.5 m/s) and running (2.5 m/s) can be reduced by 6.2% and 4.0% with the multiarticular energy modulation of a hip-knee unpowered exoskeleton, compared to that of walking and running without an exoskeleton. The bio-inspired design method of this study may inspire people to develop devices that assist multiple gaits in the future.


Assuntos
Exoesqueleto Energizado , Humanos , Caminhada/fisiologia , Marcha/fisiologia , Articulação do Joelho/fisiologia , Joelho/fisiologia , Fenômenos Biomecânicos
19.
Sensors (Basel) ; 22(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36366248

RESUMO

Multi-source information fusion technology is a kind of information processing technology which comprehensively processes and utilizes multi-source uncertain information. It is an effective scheme to solve complex pattern recognition and improve classification performance. This study aims to improve the accuracy and robustness of exoskeleton gait pattern transition recognition in complex environments. Based on the theory of multi-source information fusion, this paper explored a multi-source information fusion model for exoskeleton gait pattern transition recognition in terms of two aspects of multi-source information fusion strategy and multi-classifier fusion. For eight common gait pattern transitions (between level and stair walking and between level and ramp walking), we proposed a hybrid fusion strategy of multi-source information at the feature level and decision level. We first selected an optimal feature subset through correlation feature extraction and feature selection algorithm, followed by the feature fusion through the classifier. We then studied the construction of a multi-classifier fusion model with a focus on the selection of base classifier and multi-classifier fusion algorithm. By analyzing the classification performance and robustness of the multi-classifier fusion model integrating multiple classifier combinations with a number of multi-classifier fusion algorithms, we finally constructed a multi-classifier fusion model based on D-S evidence theory and the combination of three SVM classifiers with different kernel functions (linear, RBF, polynomial). Such multi-source information fusion model improved the anti-interference and fault tolerance of the model through the hybrid fusion strategy of feature level and decision level and had higher accuracy and robustness in the gait pattern transition recognition, whose average recognition accuracy for eight gait pattern transitions reached 99.70%, which increased by 0.15% compared with the highest average recognition accuracy of the single classifier. Moreover, the average recognition accuracy in the absence of different feature data reached 97.47% with good robustness.


Assuntos
Exoesqueleto Energizado , Reconhecimento Automatizado de Padrão , Algoritmos , Marcha , Caminhada
20.
Sensors (Basel) ; 22(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36366250

RESUMO

Neurorehabilitation research in patients with traumatic brain injury (TBI) showed how vestibular rehabilitation (VR) treatments positively affect concussion-related symptoms, but no studies have been carried out in patients with severe TBI (sTBI) during post-acute intensive neurorehabilitation. We aimed at testing this effect by combining sensor-based gait analysis and clinical scales assessment. We hypothesized that integrating VR in post-acute neurorehabilitation training might improve gait quality and activity of daily living (ADL) in sTBI patients. A two-arm, single-blind randomized controlled trial with 8 weeks of follow-up was performed including thirty sTBI inpatients that underwent an 8-week rehabilitation program including either a VR or a conventional program. Gait quality parameters were obtained using body-mounted magneto-inertial sensors during instrumented linear and curvilinear walking tests. A 4X2 mixed model ANOVA was used to investigate session-group interactions and main effects. Patients undergoing VR exhibited improvements in ADL, showing early improvements in clinical scores. Sensor-based assessment of curvilinear pathways highlighted significant VR-related improvements in gait smoothness over time (p < 0.05), whereas both treatments exhibited distinct improvements in gait quality. Integrating VR in conventional neurorehabilitation is a suitable strategy to improve gait smoothness and ADL in sTBI patients. Instrumented protocols are further promoted as an additional measure to quantify the efficacy of neurorehabilitation treatments.


Assuntos
Atividades Cotidianas , Lesões Encefálicas Traumáticas , Humanos , Método Simples-Cego , Resultado do Tratamento , Marcha , Lesões Encefálicas Traumáticas/reabilitação
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