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1.
Gait Posture ; 111: 65-74, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38653178

RESUMO

BACKGROUND: Clinical gait analysis (CGA) is a systematic approach to comprehensively evaluate gait patterns, quantify impairments, plan targeted interventions, and evaluate the impact of interventions. However, international standards for CGA are currently lacking, resulting in various national initiatives. Standards are important to ensure safe and effective healthcare practices and to enable evidence-based clinical decision-making, facilitating interoperability, and reimbursement under national healthcare policies. Collaborative clinical and research work between European countries would benefit from common standards. RESEARCH OBJECTIVE: This study aimed to review the current laboratory practices for CGA in Europe. METHODS: A comprehensive survey was conducted by the European Society for Movement Analysis in Adults and Children (ESMAC), in close collaboration with the European national societies. The survey involved 97 gait laboratories across 16 countries. The survey assessed several aspects related to CGA, including equipment used, data collection, processing, and reporting methods. RESULTS: There was a consensus between laboratories concerning the data collected during CGA. The Conventional Gait Model (CGM) was the most used biomechanical model for calculating kinematics and kinetics. Respondents also reported the use of video recording, 3D motion capture systems, force plates, and surface electromyography. While there was a consensus on the reporting of CGA data, variations were reported in training, documentation, data preprocessing and equipment maintenance practices. SIGNIFICANCE: The findings of this study will serve as a foundation for the development of standardized guidelines for CGA in Europe.


Assuntos
Análise da Marcha , Humanos , Europa (Continente) , Inquéritos e Questionários , Sociedades Médicas , Fenômenos Biomecânicos , Criança , Adulto , Eletromiografia
2.
Clin Biomech (Bristol, Avon) ; 113: 106207, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38367481

RESUMO

BACKGROUND: Aging is associated with changes in neuromuscular control that can lead to difficulties in performing daily living tasks. Muscle synergy analysis allows the assessment of neuromuscular control strategies and functional deficits. However, the age-related changes of muscle synergies during functional tasks are scattered throughout the literature. This review aimed to synthesize the existing literature on muscle synergies in elderly people during daily-living tasks and examine how they differ from those exhibited by young adults. METHODS: The Medline, CINAHL and Web of Science databases were searched. Studies were included if they focused on muscle synergies in elderly people during walking, sit-to-stand or stair ascent, and if muscle synergies were obtained by a matrix factorization algorithm. FINDINGS: Seventeen studies were included after the screening process. The muscle synergies of 295 elderly people and 182 young adults were reported, including 5 to 16 muscles per leg, or leg and trunk. Results suggest that: 1) elderly people and young adults retain similar muscle synergies' number, 2) elderly people have higher muscles weighting during walking, and 3) an increased inter and intra-subject temporal activation variability during specific tasks (i.e., walking and stair ascent, respectively) was reported in elderly people compared to young adults. INTERPRETATION: This review gives a comprehensive understanding of age-related changes in neuromuscular control during daily living tasks. Our findings suggested that although the number of synergies remains similar, metrics such as spatial and temporal structures of synergies are more suitable to identify neuromuscular control deficits between young adults and elderly people.


Assuntos
Músculo Esquelético , Caminhada , Adulto Jovem , Humanos , Idoso , Músculo Esquelético/fisiologia , Eletromiografia , Caminhada/fisiologia , Envelhecimento/fisiologia
3.
J Anat ; 244(4): 620-627, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38214341

RESUMO

Imaging techniques in anatomy have developed rapidly over the last decades through the emergence of various 3D scanning systems. Depending on the dissection level, non-contact or tactile contact methods can be applied on the targeted structure. The aim of this study was to assess the inter and intra-observer reproducibility of an ArUco-based localisation stylus, that is, a manual technique on a hand-held stylus. Ten fresh-frozen, unembalmed adult arms were used to digitalise the glenoid cartilage related to the glenohumeral joint and the contour of the clavicle cartilage related to the acromioclavicular joint. Three operators performed consecutive digitalisations of each cartilage contour using an ArUco-based localisation stylus recorded by a single monocular camera. The shape of each cartilage was defined by nine shape parameters. Intra-observer repeatability and inter-observer reproducibility were computed using an intra-class correlation (ICC) for each of these parameters. Overall, 35.2 ± 2.4 s and 26.6 ± 10.2 s were required by each examiner to digitalise the contour of a glenoid and acromioclavicular cartilage, respectively. For most parameters, good-to-excellent agreements were observed concerning intra-observer (ICC ranging between 0.81 and 1.00) and inter-observer (ICC ranging between 0.75 and 0.99) reproducibility. To conclude, through a fast and versatile process, the use of an ArUco-based localisation stylus can be a reliable low-cost alternative to conventional imaging methods to digitalise shoulder cartilage contours.


Assuntos
Articulação do Ombro , Ombro , Adulto , Humanos , Reprodutibilidade dos Testes , Variações Dependentes do Observador , Cartilagem
4.
Gait Posture ; 107: 155-161, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37781901

RESUMO

BACKGROUND: Using a machine learning algorithm, individuals can be accurately identified from their muscle activation patterns during gait, leading to the concept of individual muscle activation signatures. RESEARCH QUESTION: Are muscle activation signatures robust across different walking speeds? METHODS: We used an open dataset containing electromyographic (EMG) signals from 8 lower limb muscles in 50 asymptomatic adults walking at 5 speeds (extremely slow, very slow, slow, spontaneous, and fast). A machine learning approach classified the EMG profiles based on similar (intra-speed classification) or different (inter-speed classification) walking speeds as training and testing conditions. RESULTS: Intra-speed median classification rates of muscle activation profiles increased with walking speed, from 92 % for extremely slow, to 100 % for self-selected fast walking conditions. Inter-speed median classification rates increased when the speed of the training condition was closer to that of the testing condition. Higher median classification rates were found across slow, spontaneous, and fast walking speed conditions, from 56 % to 96 %, compared with classification rates involving extremely and very slow walking speed conditions, from 6 % to 62 %. SIGNIFICANCE: Our findings reveal that i) muscle activation signatures are detectable for a large range of walking speeds, even those involving different gait strategies (intra-speed median classification rates from 92 % to 100 %), and ii) muscle activation signatures observed during very low walking speeds are not consistent with those observed at higher speeds, suggesting a difference in motor control strategy. Caution should therefore be exercised when assessing gait deviations of a slow walking patient against a normative database obtained at higher speed. Identifying the robustness of individual muscle activation signatures across different movements could help in detecting changes in motor control, otherwise difficult to detect on classical time-varying EMG patterns.


Assuntos
Músculo Esquelético , Velocidade de Caminhada , Adulto , Humanos , Músculo Esquelético/fisiologia , Eletromiografia , Marcha/fisiologia , Caminhada/fisiologia
5.
Eur J Phys Rehabil Med ; 59(6): 669-681, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37869760

RESUMO

BACKGROUND: In post-stroke hemiparetic subjects, a systematic and quantified description of the shortening default and compensatory movements during the swing phase of gait is essential to guide treatments and assess the impact of therapeutic interventions. However, such a systematic approach does not exist in the current clinical practice. AIM: The aim of this study was to present a method improving the quantification and visualization of the kinematics of both lower limbs during the swing phase of gait, more specifically the origin of shortening default and the weight of compensations, based on a tool specifically developed: ToulGaitViz. DESIGN: Observational cohort study. SETTING: Three-dimensional kinematic gait analyses of outpatients evaluated in Toulouse university hospital. POPULATION: ToulGaitViz was applied to 151 post-stroke hemiparetic participants and 48 healthy control participants. METHODS: ToulGaitViz is a standalone software allowing to compute 1) limb clearance as the sum of the shortening related to hip, knee and ankle flexion in the sagittal plane; 2) compensations related to the abduction of the limb and hip hiking at mid-swing. Both centimetric and angular values of the clearance were reported as well as their correlations with walking speed. RESULTS: Overall, the contribution of compensations in clearance was higher in post-stroke hemiparetic subjects than in healthy control participants with both centimetric (130% vs. 33%; P<0.001) and angular methods (23% vs. 1.4%; P<0.001). The centimetric method better represents the specific contribution of each segment to the clearance than the angular method. Symbolically, mean kinematic data from the cohort supports the claim that 2° of pelvic obliquity is equivalent to 10° of knee flexion to increase clearance by 1 cm, emphasizing the non-proportionality between the angular values and the actual contribution to the shortening. ToulGaitViz allows visualization of clearance, segmental shortening and compensation evolution before and after any therapeutic intervention with quantitative and comprehensive data. CONCLUSIONS: The ToulGaitViz could be systematically used in clinical practice to extract relevant kinematic data from the origin of shortening default and the weight of compensations. CLINICAL REHABILITATION IMPACT: This tool allows better understanding of the mechanisms of action of treatments to better link them to the subjects' needs.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Estudos de Coortes , Marcha , Extremidade Inferior , Acidente Vascular Cerebral/complicações , Análise da Marcha , Fenômenos Biomecânicos , Caminhada
6.
Clin Biomech (Bristol, Avon) ; 107: 106035, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37413813

RESUMO

BACKGROUND: Primary causes of surgical revision after total hip arthroplasty are polyethylene wear and implant loosening. These factors are particularly related to joint friction and thus patients' physical activity. Assessing implant wear over time according to patients' morphology and physical activity level is key to improve follow-up and patients' quality of life. METHODS: An approach initially proposed for tibiofemoral prosthetic wear estimation was adapted to compute two wear factors (force-velocity, directional wear intensity) using a musculoskeletal model. It was applied on 17 participants with total hip arthroplasty to compute joint angular velocity, contact force, sliding velocity, and wear factors during common daily living activities. FINDINGS: Differences were observed between gait, sitting down, and standing up tasks. An incremental increase of both global wear factors (time-integral) was observed during gait from slow to fast speeds (p ≤ 0.01). Interestingly, these two wear factors did not result in same trend for sitting down and standing up tasks. Compared to gait, one cycle of sitting down or standing up tends to induce higher friction-related wear but lower cross-shear-related wear. Depending on the wear factor, significant differences can be found between sitting down and gait at slow speed (p ≤ 0.05), and between sitting down (p ≤ 0.05) or standing up (p ≤ 0.05) and gait at fast speed. Furthermore, depending on the activity, wear can be fostered by joint contact force and/or sliding velocity. INTERPRETATION: This study demonstrated the potential of wear estimation to highlight activities inducing a higher risk of implant wear after total hip arthroplasty from motion capture data.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Prótese de Quadril/efeitos adversos , Qualidade de Vida , Polietileno , Marcha , Falha de Prótese
7.
Sci Rep ; 13(1): 6483, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081110

RESUMO

The identification of relevant and valid biomarkers to distinguish patients with non-specific chronic low back pain (NSCLBP) from an asymptomatic population in terms of musculoskeletal factors could contribute to patient follow-up and to evaluate therapeutic strategies. Several parameters related to movement impairments have been proposed in the literature in that respect. However, most of them were assessed in only one study, and only 8% were evaluated in terms of reliability, validity and interpretability. The aim of this study was to consolidate the current knowledge about movement biomarkers to discriminate NSCLBP patients from an asymptomatic population. For that, an experimental protocol was established to assess the reliability, validity and interpretability of a set of 72 movement biomarkers on 30 asymptomatic participants and 30 NSCLBP patients. Correlations between the biomarkers and common patient reported outcome measures were also analysed. Four biomarkers reached at least a good level in reliability (ICC ≥ 0.75) and validity (significant difference between asymptomatic participants and NSCLBP patients, p ≤ 0.01) domains and could thus be possibly considered as valuable biomarkers: maximal lumbar sagittal angle, lumbar sagittal angle range of motion, mean lumbar sagittal angular velocity, and maximal upper lumbar sagittal angle during trunk sagittal bending. These four biomarkers demonstrated typically larger values in asymptomatic participants than in NSCLBP patients. They are in general weakly correlated with patient reported outcome measures, arguing for a potential interest in including related musculoskeletal factors in the establishment of a valuable diagnosis and in guiding treatment response.


Assuntos
Dor Crônica , Dor Lombar , Humanos , Dor Lombar/diagnóstico , Reprodutibilidade dos Testes , Dor Crônica/diagnóstico , Região Lombossacral , Movimento , Amplitude de Movimento Articular/fisiologia
8.
Sci Data ; 10(1): 180, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997555

RESUMO

Human motion capture and analysis could be made easier through the use of wearable devices such as inertial sensors and/or pressure insoles. However, many steps are still needed to reach the performance of optoelectronic systems to compute kinematic parameters. The proposed dataset has been established on 10 asymptomatic adults. Participants were asked to walk at different speeds on a 10-meters walkway in a laboratory and to perform different movements such as squats or knee flexion/extension tasks. Three-dimensional trajectories of 69 reflective markers placed according to a conventional full body markerset, acceleration and angular velocity signals of 8 inertial sensors, pressure signals of 2 insoles, 3D ground reaction forces and moments obtained from 3 force plates were simultaneously recorded. Eight calculated virtual markers related to joint centers were also added to the dataset. This dataset contains a total of 337 trials including static and dynamic tasks for each participant. Its purpose is to enable comparisons between various motion capture systems and stimulate the development of new methods for gait analysis.


Assuntos
Análise da Marcha , Marcha , Adulto , Humanos , Fenômenos Biomecânicos , Caminhada , Dispositivos Eletrônicos Vestíveis
9.
J Electromyogr Kinesiol ; 68: 102740, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36549262

RESUMO

BACKGROUND: Among the main methods used to identify an altered flexion relaxation phenomenon (FRP) in nonspecific chronic low back pain (NSCLBP), it has been previously demonstrated that flexion relaxation ratio (FRR) and extension relaxation ratio (ERR) are more objective than the visual reference method. OBJECTIVE: To determine the sensitivity and specificity of the different methods used to calculate the ratios in terms of their ability to identify an altered FRP in NSCLBP. METHODS: Forty-four NSCLBP patients performed a standing maximal trunk flexion task. Surface electromyography (sEMG) was recorded along the erector spinae longissimus (ESL) and multifidus (MF) muscles. Altered FRP based on sEMG was visually identified by three experts (current standard). Six FRR methods and five ERR methods were used both for the ESL and MF muscles. ROC curves (with areas under the curve (AUC) and sensitivity/specificity) were generated for each ratio. RESULTS: All methods used to calculate these ratios had an AUC higher than 0.9, excellent sensitivity (>90 %), and good specificity (80-100 %) for both ESL and MF muscles. CONCLUSION: Both FRP ratios (FRR and ERR) for MF and ESL muscles, appear to be an objective, sensitive and specific method for identifying altered FRP in NSCLBP patients.


Assuntos
Dor Lombar , Humanos , Dor Lombar/diagnóstico , Músculos Paraespinais , Contração Muscular/fisiologia , Relaxamento Muscular/fisiologia , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular/fisiologia , Eletromiografia/métodos
10.
Sci Data ; 9(1): 399, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821499

RESUMO

Clinical gait analysis is a promising approach for quantifying gait deviations and assessing the impairments altering gait in patients with osteoarthritis. There is a lack of consensus on the identification of kinematic outcomes that could be used for the diagnosis and follow up in patients. The proposed dataset has been established on 80 asymptomatic participants and 106 patients with unilateral hip osteoarthritis before and 6 months after arthroplasty. All volunteers walked along a 6 meters straight line at their self-selected speed. Three dimensional trajectories of 35 reflective markers were simultaneously recorded and Plugin Gait Bones, angles, Center of Mass trajectories and ground reaction forces were computed. Gait video recordings, when available, anthropometric and demographic descriptions are also available. A minimum of 10 trials have been made available in the weka file format and C3D file to enhance the use of machine learning algorithms. We aim to share this dataset to facilitate the identification of new movement-related kinematic outcomes for improving the diagnosis and follow up in patients with hip OA.


Assuntos
Artroplastia de Quadril , Osteoartrite do Quadril , Marcha , Análise da Marcha , Voluntários Saudáveis , Humanos , Osteoartrite do Quadril/reabilitação , Osteoartrite do Quadril/cirurgia
11.
Gait Posture ; 91: 161-164, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34736094

RESUMO

BACKGROUND: Electromyography (EMG) signal amplitude is often altered by factors related to the participants and the measurement system. To overcome this issue, a normalisation of the EMG signal amplitude can be performed. Recently, it has been demonstrated that a submaximal voluntary contraction (subMVC) normalisation approach, inspired by grade 3 of manual muscle testing, could produce reliable results. However, rectus femoris (RF) normalisation resulted in low reliability. While the normalisation task chosen for this biarticular muscle was to maintain a knee extension against gravity (ISO-K), a hip flexion isometric task (ISO-H) could also be applied. RESEARCH QUESTION: This pilot study aimed to assess the impact of the normalisation task on the RF EMG signal quality and related intra-rater within-day reliability during ISO-K and ISO-H, and intra-rater between-day reliability of the EMG signal amplitude during gait. METHODS: Twenty-four asymptomatic participants were asked to perform ISO-K and ISO-H tasks with both legs and then to walk at self-spontaneous speed, in two identical sessions one week apart. A wireless EMG system was used to record the EMG signal of bilateral RF during each task. RESULTS: Signal-to-noise ratio during ISO-K and ISO-H was ≥ 15 dB in respectively 51% and 98% of all task repetitions. Intra-rater within-day reliability was acceptable using ISO-K (ICC = 0.71 (0.57; 0.83)) with high %SEM of 35%, and excellent using ISO-H (ICC = 0.94 (0.90; 0.96)) with high %SEM of 34%. Intra-rater between-day reliability during gait was acceptable using ISO-K (ICC = 0.74 (0.61; 0.81)) with a high %SEM of 49%, and excellent using ISO-H (ICC = 0.87 (0.76; 0.93)) with a high %SEM of 38%. SIGNIFICANCE: The reliability (ICC) of RF EMG signal normalisation was higher using ISO-H than using ISO-K. However, even if signal-to-noise ratio was notably improved using ISO-H, %SEM remains high whatever the normalisation task used. Some additional improvements might thus still be needed to obtain a normalisation protocol allowing more reproducible measurements.


Assuntos
Contração Isométrica , Músculo Quadríceps , Eletromiografia , Humanos , Contração Muscular , Músculo Esquelético , Projetos Piloto , Reprodutibilidade dos Testes
12.
Front Hum Neurosci ; 15: 720699, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34588967

RESUMO

For interpreting outcomes of clinical gait analysis, an accurate estimation of gait events, such as initial contact (IC) and toe-off (TO), is essential. Numerous algorithms to automatically identify timing of gait events have been developed based on various marker set configurations as input. However, a systematic overview of the effect of the marker selection on the accuracy of estimating gait event timing is lacking. Therefore, we aim to evaluate (1) if the marker selection influences the accuracy of kinematic algorithms for estimating gait event timings and (2) what the best marker location is to ensure the highest event timing accuracy across various gait patterns. 104 individuals with cerebral palsy (16.0 ± 8.6 years) and 31 typically developing controls (age 20.6 ± 7.8) performed clinical gait analysis, and were divided into two out of eight groups based on the orientation of their foot, in sagittal and frontal plane at mid-stance. 3D marker trajectories of 11 foot/ankle markers were used to estimate the gait event timings (IC, TO) using five commonly used kinematic algorithms. Heatmaps, for IC and TO timing per group were created showing the median detection error, compared to detection using vertical ground reaction forces, for each marker. Our findings indicate that median detection errors can be kept within 7 ms for IC and 13 ms for TO when optimizing the choice of marker and detection algorithm toward foot orientation in midstance. Our results highlight that the use of markers located on the midfoot is robust for detecting gait events across different gait patterns.

13.
J Hand Surg Eur Vol ; 46(10): 1088-1095, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34002642

RESUMO

We performed a cadaver study using 18 fresh-frozen adult forearms and hands to compare the tendon loads required to generate progressively greater key pinch (0.5 kg to 2 kg) after three different surgical procedures to treat trapeziometacarpal osteoarthritis: isolated trapeziectomy, trapeziectomy followed by ligament reconstruction with tendon interposition and total joint arthroplasty using a Touch® implant. Thumb pinch was simulated by loading the main actuator tendons involved in the key pinch. Six specimens were randomly assigned to each of the three surgical procedure groups. Measurements were made before and after the joint surgery. Specimens that underwent trapeziectomy with or without ligament reconstruction with tendon interposition required significantly higher tendon loads than those with the implant to achieve the same pinch force. There was no significant difference between the isolated trapeziectomy and ligament reconstruction groups. Using the implant resulted in similar median tendon loads compared with those of the intact sample. Total joint arthroplasty with a Touch® prosthesis may yield a superior biomechanical profile in which the tendon loads needed to achieve a certain key pinch force are lower and better distributed between the actuator muscles compared with trapeziectomy with or without ligament reconstruction.


Assuntos
Osteoartrite , Trapézio , Adulto , Artroplastia , Cadáver , Humanos , Osteoartrite/cirurgia , Tendões/cirurgia , Polegar/cirurgia , Trapézio/cirurgia
14.
Sci Rep ; 11(1): 5850, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712658

RESUMO

The identification of relevant and valid biomarkers to distinguish patients with non-specific chronic low back pain (NSCLBP) from an asymptomatic population in terms of musculoskeletal factors could contribute to patient follow-up and to evaluate therapeutic strategies. Several parameters related to movement and/or muscular activity impairments have been proposed in the literature in that respect. In this article, we propose a systematic and comprehensive review of these parameters (i.e. potential biomarkers) and related measurement properties. This systematic review (PROSPERO registration number: CRD42020144877) was conducted in Medline, Embase, and Web of Knowledge databases until July 2019. In the included studies, all movements or muscular activity parameters having demonstrated at least a moderate level of construct validity were defined as biomarkers, and their measurement properties were assessed. In total, 92 studies were included. This allowed to identify 121 movement and 150 muscular activity biomarkers. An extensive measurement properties assessment was found in 31 movement and 14 muscular activity biomarkers. On the whole, these biomarkers support the primary biomechanical concepts proposed for low back pain. However, a consensus concerning a robust and standardised biomechanical approach to assess low back pain is needed.


Assuntos
Biomarcadores/metabolismo , Dor Crônica/fisiopatologia , Dor Lombar/fisiopatologia , Movimento/fisiologia , Músculos/fisiopatologia , Geografia , Humanos
16.
J Biomech ; 113: 110117, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33197692

RESUMO

Accurate estimation of the tibiofemoral contact forces relies on exact kinematics and joint geometry. Subject-specific kinematic constraints representing contact point trajectories derived from fluoroscopic measurements during lunge are introduced in a musculoskeletal model of the lower limb and compared to generic kinematic constraints. The medial, lateral, and total contact forces during gait and squat are validated using the data of four patients with an instrumented prosthesis. The accuracy of the estimated contact forces (both with subject-specific and generic kinematic constraints) remains close to the level reported in the literature. The mean root mean square errors range from 0.32 to 0.52 body weights for gait and from 0.27 to 0.72 body weights for squat. The impact of the subject-specific contact point trajectories is not found substantial or consistent between patients and tasks. Indeed, the kinematics of the total knee prostheses remains close to the kinematics of a hinge joint and the contact point locations remain generally centred at 20 mm from the tibia centreline (close to the constant value defined in the generic constraints). The contact point trajectories are also suspected to differ between tasks (lunge vs. gait and squat). While the contact point trajectories have been reported to be sensitive model parameters, no clear improvement of the contact force accuracy is demonstrated on patients with instrumented prosthesis. The introduction (as kinematic constraints) of fluoroscopy-based contact point trajectories may be considered in cases where these trajectories are significantly altered, as reported for osteoarthritis patients.


Assuntos
Articulação do Joelho , Tíbia , Fenômenos Biomecânicos , Fluoroscopia , Marcha , Humanos , Articulação do Joelho/diagnóstico por imagem , Tíbia/diagnóstico por imagem
17.
J Biomech ; 95: 109329, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31522745

RESUMO

Musculoskeletal models generally solve the muscular redundancy by numerical optimisation. They have been extensively validated using instrumented implants. Conversely, a reduction approach considers only one flexor or extensor muscle group at the time to equilibrate the inter-segmental joint moment. It is not clear if such models can still predict reliable joint contact and musculo-tendon forces during gait. Tibiofemoral contact force and gastrocnemii, quadriceps, and hamstrings musculo-tendon forces were estimated using a reduction approach for five subjects walking with an instrumented prosthesis. The errors in the proximal-distal tibiofemoral contact force fell in the range (0.3-0.9 body weight) reported in the literature for musculoskeletal models using numerical optimisation. The musculo-tendon forces were in agreement with the EMG envelops and appeared comparable to the ones reported in the literature with generic musculoskeletal models. Although evident simplifications and limitations, it seems that the reduction approach can provided quite reliable results. It can be a useful pedagogical tool in biomechanics, e.g. to illustrate the theoretical differences between inter-segmental and contact forces, and can provide a first estimate of the joint loadings in subjects with limited musculoskeletal deformities and neurological disorders.


Assuntos
Articulações/fisiologia , Fenômenos Mecânicos , Modelos Biológicos , Músculo Esquelético/fisiologia , Tendões/fisiologia , Fenômenos Biomecânicos , Eletromiografia , Marcha , Humanos , Suporte de Carga
18.
Front Neurorobot ; 13: 48, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379547

RESUMO

In the context of neuro-orthopedic pathologies affecting walking and thus patients' quality of life, understanding the mechanisms of gait deviations and identifying the causal motor impairments is of primary importance. Beside other approaches, neuromusculoskeletal simulations may be used to provide insight into this matter. To the best of our knowledge, no computational framework exists in the literature that allows for predictive simulations featuring muscle co-contractions, and the introduction of various types of perturbations during both healthy and pathological gait types. The aim of this preliminary study was to adapt a recently proposed EMG-marker tracking optimization process to a lower limb musculoskeletal model during equinus gait, a multiphase problem with contact forces. The resulting optimization method tracking EMG, ground reactions forces, and marker trajectories allowed an accurate reproduction of joint kinematics (average error of 5.4 ± 3.3 mm for pelvis translations, and 1.9 ± 1.3° for pelvis rotation and joint angles) and ensured good temporal agreement in muscle activity (the concordance between estimated and measured excitations was 76.8 ± 5.3 %) in a relatively fast process (3.88 ± 1.04 h). We have also highlighted that the tracking of ground reaction forces was possible and accurate (average error of 17.3 ± 5.5 N), even without the use of a complex foot-ground contact model.

19.
Sci Rep ; 9(1): 9510, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267006

RESUMO

Clinical gait analysis attempts to provide, in a pathological context, an objective record that quantifies the magnitude of deviations from normal gait. However, the identification of deviations is highly dependent with the characteristics of the normative database used. In particular, a mismatch between patient characteristics and an asymptomatic population database in terms of walking speed, demographic and anthropometric parameters may lead to misinterpretation during the clinical process. Rather than developing a new normative data repository that may require considerable of resources and time, this study aims to assess a method for predicting lower limb sagittal kinematics using multiple regression models based on walking speed, gender, age and BMI as predictors. With this approach, we were able to predict kinematics with an error within 1 standard deviation of the mean of the original waveforms recorded on fifty-four participants. Furthermore, the proposed approach allowed us to estimate the relative contribution to angular variations of each predictor, independently from the others. It appeared that a mismatch in walking speed, but also age, sex and BMI may lead to errors higher than 5° on lower limb sagittal kinematics and should thus be taken into account before any clinical interpretation.


Assuntos
Marcha , Extremidade Inferior/fisiologia , Velocidade de Caminhada , Adulto , Fatores Etários , Idoso , Fenômenos Biomecânicos , Índice de Massa Corporal , Feminino , Humanos , Extremidade Inferior/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
20.
Sci Data ; 6(1): 111, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270327

RESUMO

Human motion capture is used in various fields to analyse, understand and reproduce the diversity of movements that are required during daily-life activities. The proposed dataset of human gait has been established on 50 adults healthy and injury-free for lower and upper extremities in the most recent six months, with no lower and upper extremity surgery in the last two years. Participants were asked to walk on a straight level walkway at 5 speeds during one unique session: 0-0.4 m.s-1, 0.4-0.8 m.s-1, 0.8-1.2 m.s-1, self-selected spontaneous and fast speeds. Three dimensional trajectories of 52 reflective markers spread over the whole body, 3D ground reaction forces and moment, and electromyographic signals were simultaneously recorded. For each participants, a minimum of 3 trials per condition have been made available in the dataset for a total of 1143 trials. This dataset could increase the sample size of similar datasets, lead to analyse the effect of walking speed on gait or conduct unusual analysis of gait thanks to the full body markerset used.


Assuntos
Marcha , Caminhada , Adulto , Fenômenos Biomecânicos , Humanos
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