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1.
PLoS Comput Biol ; 19(4): e1011042, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37023170

RESUMO

Healthy skeletal muscle undergoes repair in response to mechanically localised strains during activities such as exercise. The ability of cells to transduce the external stimuli into a cascade of cell signalling responses is important to the process of muscle repair and regeneration. In chronic myopathies such as Duchenne muscular dystrophy and inflammatory myopathies, muscle is often subject to chronic necrosis and inflammation that perturbs tissue homeostasis and leads to non-localised, widespread damage across the tissue. Here we present an agent-based model that simulates muscle repair in response to both localised eccentric contractions similar to what would be experienced during exercise, and non-localised widespread inflammatory damage that is present in chronic disease. Computational modelling of muscle repair allows for in silico exploration of phenomena related to muscle disease. In our model, widespread inflammation led to delayed clearance of tissue damage, and delayed repair for recovery of initial fibril counts at all damage levels. Macrophage recruitment was delayed and significantly higher in widespread compared to localised damage. At higher damage percentages of 10%, widespread damage led to impaired muscle regeneration and changes in muscle geometry that represented alterations commonly observed in chronic myopathies, such as fibrosis. This computational work offers insight into the progression and aetiology of inflammatory muscle diseases, and suggests a focus on the muscle regeneration cascade in understanding the progression of muscle damage in inflammatory myopathies.


Assuntos
Distrofia Muscular de Duchenne , Miosite , Humanos , Músculo Esquelético/fisiologia , Fibras Musculares Esqueléticas , Inflamação
2.
J Sports Sci ; 41(10): 972-989, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37742342

RESUMO

Badminton footwork has been characterised with jump-landing, cross step, side side and lunges, which requires movement agility to facilitate on-court performance. A novel badminton shoe design with systematic increase of lateral wedge hardness (Asker C value of 55, 60, 65, and 70) was developed and investigated in this study, aiming to analyse the dose-response effect of incremental wedge hardness on typical badminton footwork. Stance time and joint stiffness were employed to investigate the footwork performance, and the factorial Statistical non-Parametric Mapping and Principal Component Analysis (PCA) were used to quantify the biomechanical responses over the stance. As reported, shorter contact times (decreased by 8.9%-13.5%) and increased joint stiffness (in side step) of foot-ankle complex were found, suggesting improved footwork stability and agility from increased hardness. Time-varying differences were noted during the initial landing and driving-off phase of cross and side steps and drive-off returning of lunges, suggesting facilitated footwork performance. The reconstructed modes of variations from PCA further deciphered the biomechanical response to the wedge dosage, especially during drive-off, to understand the improved footwork agility and stability.


Assuntos
Extremidade Inferior , Esportes com Raquete , Humanos , Fenômenos Biomecânicos/fisiologia , Dureza , Extremidade Inferior/fisiologia , Articulações/fisiologia , Esportes com Raquete/fisiologia
3.
J Appl Biomech ; 39(5): 304-317, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37607721

RESUMO

In this narrative review, we explore developments in the field of computational musculoskeletal model personalization using the Physiome and Musculoskeletal Atlas Projects. Model geometry personalization; statistical shape modeling; and its impact on segmentation, classification, and model creation are explored. Examples include the trapeziometacarpal and tibiofemoral joints, Achilles tendon, gastrocnemius muscle, and pediatric lower limb bones. Finally, a more general approach to model personalization is discussed based on the idea of multiscale personalization called scaffolds.


Assuntos
Tendão do Calcâneo , Modelagem Computacional Específica para o Paciente , Humanos , Criança , Músculo Esquelético/fisiologia , Articulação do Joelho , Modelos Estatísticos
4.
J Anat ; 240(4): 746-760, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34750816

RESUMO

The aim of this review was to report on the imaging modalities used to assess morphological and architectural properties of the m. triceps surae muscle in typically developing children, and the available reliability analyses. Scopus and MEDLINE (Pubmed) were searched systematically for all original articles published up to September 2020 measuring morphological and architectural properties of the m. triceps surae in typically developing children (18 years or under). Thirty eligible studies were included in this analysis, measuring fibre bundle length (FBL) (n = 11), pennation angle (PA) (n = 10), muscle volume (MV) (n = 16) and physiological cross-sectional area (PCSA) (n = 4). Three primary imaging modalities were utilised to assess these architectural parameters in vivo: two-dimensional ultrasound (2DUS; n = 12), three-dimensional ultrasound (3DUS; n = 9) and magnetic resonance imaging (MRI; n = 6). The mean age of participants ranged from 1.4 years to 18 years old. There was an apparent increase in m. gastrocnemius medialis MV and pCSA with age; however, no trend was evident with FBL or PA. Analysis of correlations of muscle variables with age was limited by a lack of longitudinal data and methodological variations between studies affecting outcomes. Only five studies evaluated the reliability of the methods. Imaging methodologies such as MRI and US may provide valuable insight into the development of skeletal muscle from childhood to adulthood; however, variations in methodological approaches can significantly influence outcomes. Researchers wishing to develop a model of typical muscle development should carry out longitudinal architectural assessment of all muscles comprising the m. triceps surae utilising a consistent approach that minimises confounding errors.


Assuntos
Perna (Membro) , Músculo Esquelético , Adolescente , Criança , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/anatomia & histologia , Reprodutibilidade dos Testes , Ultrassonografia/métodos , Adulto Jovem
5.
J Anat ; 240(3): 567-578, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34693531

RESUMO

This study assessed the intra-acquirer, intra- and inter-processor reliability, and validity of the in vivo assessment of the medial gastrocnemius (MG), lateral gastrocnemius (LG) and soleus (SOL) muscle volumes using freehand 3D ultrasound (3DUS) in typically developing infants. Reliability assessments of freehand 3DUS were undertaken in infants across three ages groups: three, six and twelve months of age, with validity testing completed against magnetic resonance imaging (MRI) in infants at 3 months of age. Freehand 3DUS scanning was carried out by a single acquirer, with two independent processors manually segmenting images to render volumes. MRI images were segmented independently by a separate processor, with the volumes compared to those obtained via freehand 3DUS. Reliability was assessed using intraclass correlation (ICC), coefficient of variance (CV) and minimal detectable change (MDC) across each assessment time point. Validity was assessed using the limits of agreement. ICCs for intra-acquirer reliability of the acquisition process for freehand 3DUS ranged from 0.91 to 0.99 across all muscles. ICCs for intra-processor and inter-processor reliability for the segmentation process of freehand 3DUS ranged from 0.80 to 0.98 across all muscles. Acceptable levels of agreement between muscle volume obtained by freehand 3DUS and MRI were found for all muscles; however, freehand 3DUS overestimated muscle volume of MG and LG and underestimate the SOL compared with MRI, with average absolute differences of MG = 0.3 ml, LG = 0.3 ml and Sol = 1.2 ml. Freehand 3DUS is a reliable method for measuring in vivo triceps surae muscle volume in typically developing infants. We conclude that freehand 3DUS is a useful tool to assess changes in muscle volume in response to growth and interventions in infants.


Assuntos
Imageamento Tridimensional , Músculo Esquelético , Humanos , Imageamento Tridimensional/métodos , Lactente , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Reprodutibilidade dos Testes , Ultrassonografia/métodos
6.
Clin Anat ; 35(6): 745-761, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35437820

RESUMO

The paranasal sinuses (maxillary, frontal, ethmoid, and sphenoid sinuses) are complex anatomical structures. The development and growth of these have been investigated utilizing a number of different methods ranging from cadaveric analysis to modern cross sectional imaging with 3D modeling. An understanding of normal pediatric paranasal sinus embryology and development enables us to better determine when pathology may be affecting the normal developmental process. Cystic fibrosis, chronic sinusitis, deviated nasal septum and cleft lip and palate are some of the conditions which have been shown to effect paranasal sinus development to varying degrees. Functional endoscopic sinus surgery (FESS) is becoming increasingly common and an understanding of sinus anatomy together with when periods of rapid growth occur during childhood is important clinically. Although concerns have been raised regarding the impact of FESS on facial growth, there is limited evidence of this in regards to either changes in anthropomorphic measurements or clinical assessments of symmetry post operatively.


Assuntos
Fenda Labial , Fissura Palatina , Seios Paranasais , Criança , Osso Etmoide , Humanos , Seios Paranasais/anatomia & histologia , Seios Paranasais/cirurgia , Seio Esfenoidal
7.
Brain Inj ; 35(6): 621-644, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33843389

RESUMO

Traumatic brain injury (TBI) is a major public health problem. The majority of TBIs are in the form of mild TBI (also known as concussion) with sports-related concussion (SRC) receiving public attention in recent years.Here we have performed a systematic review of the literature on the use of Diffusion Tensor Imaging (DTI) on sports-related concussion and subconcussive injuries. Our review found different patterns of change in DTI parameters between concussed and subconcussed groups. The Fractional Anisotropy (FA) was either unchanged or increased for the concussion group, while the subconcussed group generally experienced a decrease in FA. A reverse pattern was observed for Mean Diffusivity (MD) - where the concussed group experienced a decrease in MD while the subconcussed group showed an increase in MD. However, in general, discrepancies were observed in the results reported in the literature - likely due to the huge variations in DTI acquisition parameters, and image processing and analysis methods used in these studies. This calls for more comprehensive and well-controlled studies in this field, including those that combine the advanced brain imaging with biomechancial modeling and kinematic sensors - to shed light on the underlying mechanisms behind the structural changes observed from the imaging studies.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Anisotropia , Atletas , Traumatismos em Atletas/complicações , Traumatismos em Atletas/diagnóstico por imagem , Encéfalo , Concussão Encefálica/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos
8.
Sensors (Basel) ; 21(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34372377

RESUMO

(Background) Inertial Measurement Units (IMUs) provide a low-cost, portable solution to obtain functional measures similar to those captured with three-dimensional gait analysis, including spatiotemporal gait characteristics. The primary aim of this study was to determine the feasibility of a remote patient monitoring (RPM) workflow using ankle-worn IMUs measuring impact load, limb impact load asymmetry and knee range of motion in combination with patient-reported outcome measures. (Methods) A pilot cohort of 14 patients undergoing primary knee arthroplasty for osteoarthritis was prospectively enrolled. RPM in the community was performed weekly from 2 up to 6 weeks post-operatively using wearable IMUs. The following data were collected using IMUs: mobility (Bone Stimulus and cumulative impact load), impact load asymmetry and maximum knee flexion angle. In addition, scores from the Oxford Knee Score (OKS), EuroQol Five-dimension (EQ-5D) with EuroQol visual analogue scale (EQ-VAS) and 6 Minute Walk Test were collected. (Results) On average, the Bone Stimulus and cumulative impact load improved 52% (p = 0.002) and 371% (p = 0.035), compared to Post-Op Week 2. The impact load asymmetry value trended (p = 0.372) towards equal impact loading between the operative and non-operative limb. The mean maximum flexion angle achieved was 99.25° at Post-Operative Week 6, but this was not significantly different from pre-operative measurements (p = 0.1563). There were significant improvements in the mean EQ-5D (0.20; p = 0.047) and OKS (10.86; p < 0.001) scores both by 6 weeks after surgery, compared to pre-operative scores. (Conclusions) This pilot study demonstrates the feasibility of a reliable and low-maintenance workflow system to remotely monitor post-operative progress in knee arthroplasty patients. Preliminary data indicate IMU outputs relating to mobility, impact load asymmetry and range of motion can be obtained using commercially available IMU sensors. Further studies are required to directly correlate the IMU sensor outputs with patient outcomes to establish clinical significance.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/cirurgia , Projetos Piloto , Amplitude de Movimento Articular
9.
AIDS Behav ; 23(8): 2121-2129, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30259346

RESUMO

Non-adherence remains the largest cause of treatment failure to antiretroviral therapy (ART). Despite having the largest HIV pandemic, few successful adherence interventions have been conducted in South Africa. Active visualisation is a novel intervention approach that may help effectively communicate the need for consistent adherence to ART. The current study tested an active visualisation intervention in a sample of non-adherent patients. 111 patients failing on first- or second-line ART were recruited from two sites in the Western Cape, South Africa. Participants were randomly allocated to receive the intervention or standard care (including adherence counselling). The primary outcome was adherence as measured by plasma viral load (VL). There was a clinically significant difference (p = 0.06) in VL change scores between groups from baseline to follow-up, where the intervention had a greater decrease in log VL (Madj = - 1.92, CI [- 2.41, - 1.43), as compared to the control group (Madj = - 1.24, [- 1.76, - 0.73]). Participants in the intervention group were also significantly more likely to have a 0.5 log improvement in VL at follow-up ([Formula: see text] = 4.82, p = 0.028, ɸ = 0.28). This study provides initial evidence for the utility of this novel, brief intervention as an adjunct to standard adherence counselling, for improving adherence to ART.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Aconselhamento , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Cooperação do Paciente , Adulto , Feminino , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , África do Sul , Falha de Tratamento , Carga Viral/efeitos dos fármacos
10.
Ann Behav Med ; 51(6): 899-911, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28474286

RESUMO

BACKGROUND: Osteoporosis is a degenerative bone disorder that disproportionately affects older women worldwide. Raising awareness regarding osteoporosis within this demographic is significant for health promotion. Initial evidence suggests that visualisations of illness and treatment can improve illness perceptions, increase treatment motivations and even promote health behaviours. We are yet to understand whether different visualisation mediums vary in their impact on perceptions and motivations. PURPOSE: We investigated whether physical models or virtual animations had a greater impact on changing perceptions of osteoporosis and treatment motivation in an at-risk population of older women. METHODS: A total of 128 women aged 50 and over were randomly assigned to view a brief presentation about osteoporosis using either 3-D printed bone models or electronic tablet animations. Illness perceptions, medication beliefs and motivations were measured at baseline and post-presentation. Mixed ANOVAs were used to identify significant changes over time between groups. RESULTS: There were no significant interaction effects, revealing that neither medium had a greater impact on beliefs over time. Significant main effects of time revealed that from baseline to post-presentation, both mediums increased consequence beliefs, personal and treatment control, understanding of osteoporosis, motivations to take treatment if needed and medication necessity beliefs. Timeline beliefs and medication concerns decreased over time for both groups. CONCLUSIONS: Both 3-D models and animations of osteoporosis are equally effective in changing beliefs and treatment motivation in an at-risk population. Visualisation devices are brief, cost-effective, have high acceptability and have considerable clinical applicability to promote awareness and prevention.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Modelos Anatômicos , Osteoporose/psicologia , Osteoporose/terapia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Educação de Pacientes como Assunto/métodos , Idoso , Desenhos Animados como Assunto , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose/tratamento farmacológico , Resultado do Tratamento
11.
J Sports Sci ; 35(5): 457-462, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27075213

RESUMO

This study presents the kinematics and plantar pressure characteristics of eight elite national-level badminton athletes and eight recreational college-level badminton players while performing a right-forward lunge movement in a laboratory-simulated badminton court. The hypothesis was that recreational players would be significantly different from elite players in kinematics and plantar pressure measures. Vicon® motion capture and Novel® insole plantar pressure measurement were simultaneously taken to record the lower extremity kinematics and foot loading during stance. Recreational players showed significantly higher peak pressure in the lateral forefoot (P = 0.002) and force time integral in the lateral forefoot (P = 0.013) and other toes (P = 0.005). Elite athletes showed higher peak pressure in the medial forefoot (P = 0.003), hallux (P = 0.037) and force time integral in the medial forefoot (P = 0.009). The difference in landing techniques for the lunge step between elite athletes and recreational players was observed with peak ankle eversion (-38.2°±2.4° for athletes and -11.1°±3.9° for players, P = 0.015); smaller knee range of motion in the coronal and transverse planes, with differences in peak knee adduction (28.9°±6.8° for athletes and 15.7°±6.2° for players, P = 0.031); peak knee internal rotation (20.3°±1.3° for athletes and 11.8°±3.2° for players, P = 0.029) and peak hip flexion (77.3°±4.1° for athletes and 91.3°±9.3° for players, P = 0.037).


Assuntos
Pé/fisiologia , Extremidade Inferior/fisiologia , Destreza Motora/fisiologia , Esportes com Raquete/fisiologia , Fenômenos Biomecânicos , Humanos , Joelho/fisiologia , Masculino , Pressão , Amplitude de Movimento Articular , Estudos de Tempo e Movimento , Adulto Jovem
12.
J Biomech Eng ; 136(11)2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25203813

RESUMO

Periprosthetic osteolysis in the retroacetabular region with cancellous bone loss is a recognized phenomenon in the long-term follow-up of total hip replacement. The effects on load transfer in the presence of defects are less well known. A validated, patient-specific, 3D finite element (FE) model of the pelvis was used to assess changes in load transfer associated with periprosthetic osteolysis adjacent to a cementless total hip arthroplasty (THA) component. The presence of a cancellous defect significantly increased (p < 0.05) von Mises stress in the cortical bone of the pelvis during walking and a fall onto the side. At loads consistent with single leg stance, this was still less than the predicted yield stress for cortical bone. During higher loads associated with a fall onto the side, highest stress concentrations occurred in the superior and inferior pubic rami and in the anterior column of the acetabulum with larger cancellous defects.


Assuntos
Artroplastia de Quadril/efeitos adversos , Análise de Elementos Finitos , Osteólise/fisiopatologia , Ossos Pélvicos/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Suporte de Carga , Idoso , Marcha , Humanos , Masculino , Osteólise/diagnóstico por imagem , Ossos Pélvicos/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Estresse Mecânico , Tomografia Computadorizada por Raios X
13.
ScientificWorldJournal ; 2014: 785175, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24982995

RESUMO

Previous gait studies on squatting have described a rapid reversal in the direction of the tibiofemoral joint shear reaction force when going into a full weight-bearing deep knee flexion squat. The effects of such a shear reversal have not been considered with regard to the loading demand on knee implants in patients whose activities of daily living require frequent squatting. In this paper, the shear reversal effect is discussed and simulated in a finite element knee implant-bone model, to evaluate the possible biomechanical significance of this effect on femoral component loosening of high flexion implants as reported in the literature. The analysis shows that one of the effects of the shear reversal was a switch between large compressive and large tensile principal strains, from knee extension to flexion, respectively, in the region of the anterior flange of the femoral component. Together with the known material limits of cement and bone, this large mismatch in strains as a function of knee position provides new insight into how and why knee implants may fail in patients who perform frequent squatting.


Assuntos
Articulação do Joelho/fisiologia , Fenômenos Biomecânicos , Humanos , Modelos Teóricos , Estresse Mecânico , Suporte de Carga
14.
J Biomech ; 162: 111865, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37976687

RESUMO

Individuals with chronic ankle instability (CAI) suffer from the resulting sequela of repetitive lateral ankle sprains (LAS), whilst copers appear to cope with initial LAS successfully. Therefore, the aim of this study was to explore the intra-foot biomechanical differences among CAI, copers, and healthy individuals during dynamic tasks. Twenty-two participants per group were included and required to perform cutting and different landing tasks (DL: drop landing; FL: forward jump followed a landing). A five-segment foot model with 8 degrees of freedom was used to explore the intra-foot movement among these three groups. Smaller dorsiflexion angles were found in copers (DL tasks and prelanding task) and CAI (DL and FL task) compared to healthy participants. Copers presented a more eversion position compared to others during these dynamic tasks. During the descending phase of DL task, greater dorsiflexion angles in the metatarsophalangeal joint were found in copers compared to the control group. Joint moment difference was only found in the subtalar joint during the descending phase of FL task, presenting more inversion moments in copers compared to healthy participants. Copers rely on more eversion positioning to prevent over-inversion of the subtalar joint compared to CAI. Further, the foot became more unstable when conducting sport-related movements, suggesting that foot stability seems to be sensitive to the task types. These findings may help in designing and implementing interventions to restore functions of the ankle joint in CAI individuals.


Assuntos
Traumatismos do Tornozelo , Instabilidade Articular , Humanos , Tornozelo , Fenômenos Biomecânicos , Articulação do Tornozelo , , Movimento , Doença Crônica
15.
J Biomech ; 168: 112120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677027

RESUMO

Foot and ankle joint models are widely used in the biomechanics community for musculoskeletal and finite element analysis. However, personalizing a foot and ankle joint model is highly time-consuming in terms of medical image collection and data processing. This study aims to develop and evaluate a framework for constructing a comprehensive 3D foot model that integrates statistical shape modeling (SSM) with free-form deformation (FFD) of internal bones. The SSM component is derived from external foot surface scans (skin measurements) of 50 participants, utilizing principal component analysis (PCA) to capture the variance in foot shapes. The derived surface shapes from SSM then guide the FFD process to accurately reconstruct the internal bone structures. The workflow accuracy was established by comparing three model-generated foot models against corresponding skin and bone geometries manually segmented and not part of the original training set. We used the top ten principal components representing 85 % of the population variation to create the model. For prediction validation, the average Dice similarity coefficient, Hausdorff distance error, and root mean square error were 0.92 ± 0.01, 2.2 ± 0.19 mm, and 2.95 ± 0.23 mm for soft tissues, and 0.84 ± 0.03, 1.83 ± 0.1 mm, and 2.36 ± 0.12 mm for bones, respectively. This study presents an efficient approach for 3D personalized foot model reconstruction via SSM generation of the foot surface that informs bone reconstruction based on FFD. The proposed workflow is part of the open-source Musculoskeletal Atlas Project linked to OpenSim and makes it feasible to accurately generate foot models informed by population anatomy, and suitable for rigid body analysis and finite element simulation.


Assuntos
, Imageamento Tridimensional , Humanos , Pé/anatomia & histologia , Pé/fisiologia , Imageamento Tridimensional/métodos , Feminino , Masculino , Adulto , Análise de Componente Principal , Análise de Elementos Finitos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiologia , Articulação do Tornozelo/anatomia & histologia , Modelos Anatômicos , Fenômenos Biomecânicos , Tornozelo/fisiologia
16.
Comput Biol Med ; 170: 108016, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38277923

RESUMO

The ankle joint plays a crucial role in gait, facilitating the articulation of the lower limb, maintaining foot-ground contact, balancing the body, and transmitting the center of gravity. This study aimed to implement long short-term memory (LSTM) networks for predicting ankle joint angles, torques, and contact forces using inertial measurement unit (IMU) sensors. Twenty-five healthy participants were recruited. Two IMU sensors were attached to the foot dorsum and the vertical axis of the distal anteromedial tibia in the right lower limb to record acceleration and angular velocity during running. We proposed a LSTM-MLP (multilayer perceptron) model for training time-series data from IMU sensors and predicting ankle joint biomechanics. The model underwent validation and testing using a custom nested k-fold cross-validation process. The average values of the coefficient of determination (R2), mean absolute error (MAE), and mean squared error (MSE) for ankle dorsiflexion joint and moment, subtalar inversion joint and moment, and ankle joint contact forces were 0.89 ± 0.04, 0.75 ± 1.04, and 2.96 ± 4.96 for walking, and 0.87 ± 0.07, 0.88 ± 1.26, and 4.1 ± 7.17 for running, respectively. This study demonstrates that IMU sensors, combined with LSTM neural networks, are invaluable tools for evaluating ankle joint biomechanics in lower limb pathological diagnosis and rehabilitation, offering a cost-effective and versatile alternative to traditional experimental settings.


Assuntos
Articulação do Tornozelo , Marcha , Humanos , Fenômenos Biomecânicos , Caminhada ,
17.
Front Bioeng Biotechnol ; 12: 1377383, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650752

RESUMO

This study presents a comprehensive review of the correlation between tibial acceleration (TA), ground reaction forces (GRF), and tibial bone loading, emphasizing the critical role of wearable sensor technology in accurately measuring these biomechanical forces in the context of running. This systematic review and meta-analysis searched various electronic databases (PubMed, SPORTDiscus, Scopus, IEEE Xplore, and ScienceDirect) to identify relevant studies. It critically evaluates existing research on GRF and tibial acceleration (TA) as indicators of running-related injuries, revealing mixed findings. Intriguingly, recent empirical data indicate only a marginal link between GRF, TA, and tibial bone stress, thus challenging the conventional understanding in this field. The study also highlights the limitations of current biomechanical models and methodologies, proposing a paradigm shift towards more holistic and integrated approaches. The study underscores wearable sensors' potential, enhanced by machine learning, in transforming the monitoring, prevention, and rehabilitation of running-related injuries.

18.
Bioengineering (Basel) ; 11(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38247963

RESUMO

Stroke is a medical condition that affects around 15 million people annually. Patients and their families can face severe financial and emotional challenges as it can cause motor, speech, cognitive, and emotional impairments. Stroke lesion segmentation identifies the stroke lesion visually while providing useful anatomical information. Though different computer-aided software are available for manual segmentation, state-of-the-art deep learning makes the job much easier. This review paper explores the different deep-learning-based lesion segmentation models and the impact of different pre-processing techniques on their performance. It aims to provide a comprehensive overview of the state-of-the-art models and aims to guide future research and contribute to the development of more robust and effective stroke lesion segmentation models.

19.
Sports Med Open ; 10(1): 83, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068296

RESUMO

BACKGROUND: Step width is a spatial variable in the frontal plane, defined as the mediolateral distance between the heel (forefoot during sprinting) of bilateral feet at initial contact. Variations in step width may impact the lower limb biomechanics. This systematic review aimed to synthesize the published findings to determine the influence of acute changes in step width on locomotion biomechanics and provide implications for injury prevention and enhanced sports performance. METHODS: Literature was identified, selected, and appraised in accordance with the methods of a systematic review. Four electronic databases (Web of Science, MEDLINE via PubMed, Scopus, and ScienceDirect) were searched up until May 2023 with the development of inclusion criteria based on the PICO model. Study quality was assessed using the Downs and Black checklist and the measured parameters were summarized. RESULTS: Twenty-three articles and 399 participants were included in the systematic review. The average quality score of the 23 studies included was 9.39 (out of 14). Step width changed the kinematics and kinetics in the sagittal, frontal, and transverse planes of the lower limb, such as peak rearfoot eversion angle and moment, peak hip adduction angle and moment, knee flexion moment, peak knee internal rotation angle, as well as knee external rotation moment. Alteration of step width has the potential to change the stability and posture during locomotion, and evidence exists for the immediate biomechanical effects of variations in step width to alter proximal kinematics and cues to impact loading variables. CONCLUSION: Short-term changes in step width during walking, running, and sprinting influenced multiple lower extremity biomechanics. Narrower step width may result in poor balance and higher impact loading on the lower extremities during walking and running and may limit an athlete's sprint performance. Increasing step width may be beneficial for injury rehabilitation, i.e., for patients with patellofemoral pain syndrome, iliotibial band syndrome or tibial bone stress injury. Wider steps increase the supporting base and typically enhance balance control, which in turn could reduce the risks of falling during daily activities. Altering the step width is thus proposed as a simple and non-invasive treatment method in clinical practice.

20.
Comput Biol Med ; 180: 108965, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39084051

RESUMO

BACKGROUND: Single-leg landing (SL) is an essential technique in sports such as basketball, soccer, and volleyball, which is often associated with a high risk of knee-related injury. The ankle motion pattern plays a crucial role in absorbing the load shocks during SL, but the effect on the knee joint is not yet clear. This work aims to explore the effects of different ankle plantarflexion angles during SL on the risk of knee-related injury. METHODS: Thirty healthy male subjects were recruited to perform SL biomechanics tests, and one standard subject was selected to develop the finite element model of foot-ankle-knee integration. The joint impact force was used to evaluate the impact loads on the knee at various landing angles. The internal load forces (musculoskeletal modeling) and stress (finite element analysis) around the knee joint were simulated and calculated to evaluate the risk of knee-related injury during SL. To more realistically revert and simulate the anterior cruciate ligament (ACL) injury mechanics, we developed a knee musculoskeletal model that reverts the ACL ligament to a nonlinear short-term viscoelastic mechanical mechanism (strain rate-dependent) generated by the dense connective tissue as a function of strain. RESULTS: As the ankle plantarflexion angle increased during landing, both the peak knee vertical impact force (p = 0.001) and ACL force (p = 0.001) decreased significantly. The maximum von Mises stress of ACL, meniscus, and femoral cartilage decreased as the ankle plantarflexion angle increased. The overall range of variation in ACL stress was small and was mainly distributed in the femoral and tibial attachment regions, as well as in the mid-lateral region. CONCLUSION: The current findings revealed that the use of larger ankle plantarflexion angles during landing may be an effective solution to reduce knee impact load and the risk of rupture of the medial femoral attachment area in the ACL. The findings of this study have the potential to offer novel perspectives in the optimized application of landing strategies, thus giving crucial theoretical backing for decreasing the risk of knee-related injury.

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