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1.
Arq Bras Oftalmol ; 88(4)2025.
Artigo em Inglês | MEDLINE | ID: mdl-39879403

RESUMO

PURPOSE: Although the orthokeratology effects on corneal biomechanics have been proven with clinical trials, reports of stiffness parameter change are scarce. This study investigated the short-term orthokeratology effects in pediatric myopia and compared stiffness parameter changes to those published in recent clinical investigations. This prospective study aimed to investigate corneal biomechanics changes induced by short-term overnight orthokeratology treatment, focusing on stiffness parameter at A1 and stress-strain index. METHODS: Twenty-six children aged 8 to 18 were included in this study using orthokeratology lenses for two different durations: 1 day and 1 week. Corneal biomechanics were assessed using corneal visualization (Corvis) Scheimpflug technology. Measurements were taken at baseline and after each wearing session. Changes in corneal stiffness parameters and corneal curvature were analyzed. RESULTS: All parameters changed significantly after 1 week of lens wear (p<0.05), except for velocity of corneal apex at the first and second applanation times highest concavity time, radius, stiffness parameter at A1 and stress-strain index. After 1 day, central corneal thickness, first applanation time, second applanation time, deformation amplitude ratio (2 mm), and Corvis biomechanical index (CBI) remained stable (p>0.05). After 1 week, central corneal thickness and first applanation time decreased, whereas second applanation time, deformation amplitude ratio, and Corvis Biomechanical Index significantly increased. With intraocular pressure and central corneal thickness as control variables, no significant correlation was found between stress-strain index and curvature changes (p>0.05). With age as the control variable, no significant correlation was found between stress-strain index and curvature changes (p>0.05). CONCLUSIONS: Short-term orthokeratology treatment induced notable changes in several corneal biomechanical parameters. Stiffness parameter at A1 and stress-strain index are unaffected by increasing lens wear duration and do not influence the orthokeratology effect.


Assuntos
Córnea , Miopia , Procedimentos Ortoceratológicos , Humanos , Criança , Miopia/fisiopatologia , Miopia/terapia , Procedimentos Ortoceratológicos/métodos , Córnea/fisiopatologia , Córnea/fisiologia , Adolescente , Fenômenos Biomecânicos , Masculino , Feminino , Estudos Prospectivos , Fatores de Tempo , Lentes de Contato , Valores de Referência , Resultado do Tratamento
2.
Sensors (Basel) ; 25(2)2025 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-39860666

RESUMO

Axillary crutches assist people with lower limb injuries but can lead to upper limb strain with extended use. Spring-loaded crutches offer a potential solution, yet they are rarely tested in clinical settings. This study developed spring-loaded crutches with an integrated force-measuring system to analyze gait dynamics. Three prototypes, each with different spring constants (k), were tested. To measure ground reaction force (GRF), a Nylamid cover was around the crutch stem. Two participants with different weights completed a 15-m route using both the designed spring-loaded and standard crutches. Findings showed that spring-loaded crutches increased mean GFR and impulse, with the prototype matched to the user's weight yielding the best results. The study's findings suggest that when properly adjusted to the user's weight, spring-loaded crutches can offer significant improvements in gait, which may have important implications for the design of mobility assistive devices.


Assuntos
Muletas , Marcha , Humanos , Marcha/fisiologia , Desenho de Equipamento , Adulto , Masculino , Fenômenos Biomecânicos
3.
Sensors (Basel) ; 25(2)2025 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-39860738

RESUMO

Portable monitoring devices based on Inertial Measurement Units (IMUs) have the potential to serve as quantitative assessments of human movement. This article proposes a new method to identify the optimal placements of the IMUs and quantify the smoothness of the gait. First, it identifies gait events: foot-strike (FS) and foot-off (FO). Second, it segments the signals of linear acceleration and angular velocities obtained from the IMUs at four locations into steps and strides. Finally, it applies three smoothness metrics (SPARC, PM, and LDLJ) to determine the most reliable metric and the best location for the sensor, using data from 20 healthy subjects who walked an average of 25 steps on a flat surface for this study (117 measurements were processed). All events were identified with less than a 2% difference from those obtained with the photogrammetry system. The smoothness metric with the least variance in all measurements was SPARC. For the smoothness metrics with the least variance, we found significant differences between applying the metrics with the complete signal (C) and the signal segmented by strides (S). This method is practical, time-effective, and low-cost in terms of computation. Furthermore, it is shown that analyzing gait signals segmented by strides provides more information about gait progression.


Assuntos
Marcha , Humanos , Marcha/fisiologia , Masculino , Adulto , Feminino , Caminhada/fisiologia , Fenômenos Biomecânicos/fisiologia , Algoritmos , Aceleração , Adulto Jovem , Análise da Marcha/métodos
4.
J Orthop Surg Res ; 20(1): 39, 2025 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-39794807

RESUMO

BACKGROUND: Scoliosis is an idiopathic three-dimensional spine strain. The orthopedic parameter used to diagnose and evaluate the severity of the strain is Cobb's angle. This study proposes using this clinical parameter to reproduce a digital twin of the spine, calculate biomechanical stress changes, and characterize idiopathic scoliosis deformity through symmetrical degeneration of intervertebral discs, relying on patient-specific radiological measurements of the scoliotic curves. METHODS: A three-dimensional computational model of the spine was developed, where patient-specific curves were generated by modifying intervertebral disc mechanical properties via a mathematical model derived from radiological data. Validation of the model was performed by comparing the resultant scoliotic curves with patient radiological images. Finite element analysis was then used to elucidate the biomechanical effects on the spine due to the deformity. RESULTS: The model successfully replicated patient-specific thoracic scoliotic deformities, revealing a discernible relationship between disc strain and its proximity to the apex, indicating a heightened risk of disc stress closer to the apex. Moreover, "type-C" curves exhibited a greater risk of herniation compared to "type-S" curves due to differences in compressive stress distribution. CONCLUSION: This modeling approach enhances the understanding of scoliosis biomechanics, facilitating risk assessment for disc prolapse and aiding in treatment selection, including the design of condition-specific orthotics. Furthermore, it establishes a quantitative link between scoliosis severity and disc strain, integrating Cobb's angle and other orthopedic parameters into computational models to approximate patient-specific conditions.


Assuntos
Escoliose , Humanos , Escoliose/diagnóstico por imagem , Escoliose/fisiopatologia , Análise de Elementos Finitos , Fenômenos Biomecânicos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/fisiopatologia , Estresse Mecânico , Feminino , Simulação por Computador , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiopatologia , Imageamento Tridimensional/métodos , Modelagem Computacional Específica para o Paciente , Masculino , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/fisiopatologia
5.
BMC Musculoskelet Disord ; 26(1): 31, 2025 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-39780147

RESUMO

BACKGROUND: Alterations in spatiotemporal parameters during walking modify and limit movement capacity in children with obesity. This study aimed to describe and compare the alterations in spatiotemporal parameters in schoolchildren according to body weight during all phases of walking. METHODS: We carried out a cross-sectional study of 94 schoolchildren aged 6 to 12 years and divided them into three study groups (normal weight, overweight, and obesity). Subsequently, we performed a gait study using a 3D motion analysis system and extracted the spatiotemporal parameters, and we compared the parameters obtained between the study groups. RESULTS: The stride length in both limbs was lower in schoolchildren with obesity compared to the overweight group, with a mean difference of 0.08 m on the right side (CI 95% 0.01-0.16; p = 0.02) and 0.09 m on the left side (CI 95% 0.01-0.17; p = 0.02); also, on the left side, the swing speed (m/s) was lower in the children with obesity than in the normal weight group, with a mean difference of 0.23 m/s (CI 95% 0.03-0.43; p = 0.01). Lastly, the step width (m) was greater in the group of schoolchildren with obesity compared to the normal weight group, with a difference of 0.05 m (CI 95% 0.01-0.09; p = 0.01). A moderate positive correlation was found between the width of the step and the weight gain, r = 0.41 (p < 0.001). However, we found a poor correlation between right stride length (m), left side swing speed (m/s), left stride length (m), and weight gain, r = 0.26 (p = 0.01), r= -0.21 (p = 0.04) and r = 0.21 (p = 0.04), respectively. CONCLUSIONS: Spatiotemporal parameters such as stride length, swing speed, and step width were more altered in schoolchildren with obesity and correlated with body weight gain.


Assuntos
Marcha , Obesidade Infantil , Humanos , Estudos Transversais , Criança , Masculino , Feminino , Marcha/fisiologia , Obesidade Infantil/fisiopatologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/diagnóstico , Sobrepeso/epidemiologia , Sobrepeso/fisiopatologia , Análise da Marcha , Caminhada/fisiologia , Fenômenos Biomecânicos
6.
Rev Paul Pediatr ; 43: e2024069, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39841743

RESUMO

OBJECTIVE: To analyze the effect of the thoracoabdominal rebalancing (TAR) method on respiratory biomechanics, respiratory discomfort, pain sensation, and physiological parameters in moderate preterm newborns, compared to a control group. METHODS: This randomized clinical trial was conducted in a neonatal intensive care unit. The evaluation included: Neonatal Infant Pain Scale, physiological parameters, Silverman-Andersen score, and biomechanics (thoracic cirtometry and Charpy angle). The newborns were randomized into the TAR group (n=17) or control group (n=13) and subjected to the slow expiratory flow acceleration technique (SEFA). The evaluation of a single session was performed three times: before, after, and 30 minutes after the intervention. RESULTS: In the intergroup comparison, there was a significant difference in respiratory rate 30 minutes after the intervention. There was no significant difference in intra- and intergroup comparisons for pain and respiratory discomfort. Regarding biomechanics, there was a significant difference in the TAR group in the Charpy angle (between assessments 1 and 2), in the axillary cirtometry (between assessments 1 and 3), and in the xiphoid process (between assessments 2 and 3). In the control group, a significant difference was observed in the axillary line (between assessments 1 and 2; 2 and 3). CONCLUSIONS: The TAR method showed a positive effect on respiratory rate and respiratory biomechanics when compared to the control group. In both groups, the techniques did not promote respiratory discomfort or pain sensation, making them safe techniques for this population.


Assuntos
Recém-Nascido Prematuro , Humanos , Masculino , Recém-Nascido , Feminino , Fenômenos Biomecânicos , Abdome , Tórax , Unidades de Terapia Intensiva Neonatal
7.
Scand J Med Sci Sports ; 34(12): e14774, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39639795

RESUMO

Studies investigating the mechanisms influencing maximum passive joint range of motion (ROMmax) and stiffness have not objectively assessed the possible influence of stretch speed and/or arousal state. The purpose of this study was to assess the effects of arousal state and stretch speed on healthy individuals ROMmax, stiffness, gastrocnemius medialis, and soleus electromyographic activity (EMG). Fourteen participants performed one familiarization and then one testing session on separate days in the laboratory. In the familiarization (Session 1), participants practiced fast (30°/s ankle dorsiflexion) and slow (5°/s) plantar flexor stretches on an isokinetic dynamometer with the knee extended. In the experimental session (Session 2), they performed two slow, then two fast, stretches under three randomized arousal conditions: control (no music), arousing, and relaxing music. Dorsiflexion ROMmax, ankle joint stiffness, muscle activity during stretch, mean heart rate, and perception of arousal were measured. Perception of arousal was greater in the arousing than relaxing condition (p = 0.001). ROMmax was greater during fast (69.1° ± 7.8°) than slow stretches (64.9° ± 10.8°; p = 0.002) with no effect of arousal. Stiffness and EMG were higher at faster speeds, with a significantly greater percentage of stiffness observed in the arousing than the other conditions during faster stretches (p = 0.04). ROMmax was greater at the faster stretch speed despite greater stiffness and muscle activities being produced during the stretch. Thus, despite reflexive muscle activity and viscosity being higher during faster stretches, a greater, not lesser, ROMmax was observed. Arousal state, at least when altered by music, did not seem to affect ROMmax but somewhat influenced stiffness in the faster stretches.


Assuntos
Articulação do Tornozelo , Nível de Alerta , Eletromiografia , Exercícios de Alongamento Muscular , Músculo Esquelético , Amplitude de Movimento Articular , Humanos , Articulação do Tornozelo/fisiologia , Nível de Alerta/fisiologia , Amplitude de Movimento Articular/fisiologia , Masculino , Adulto Jovem , Músculo Esquelético/fisiologia , Adulto , Feminino , Exercícios de Alongamento Muscular/fisiologia , Fenômenos Biomecânicos , Frequência Cardíaca/fisiologia , Música
8.
PLoS One ; 19(12): e0314909, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39652591

RESUMO

INTRODUCTION: The kinetic chain is important in the proximal-distal energy transfer along body segments. Although biomechanical impairments in components of the kinetic chain have already been reported in athletes with shoulder pain, such investigations in non-athlete individuals have not yet been synthesized. OBJECTIVE: To systematically review the literature and analyze the quality of evidence on the characteristics of the kinetic chain of non-athletes with shoulder pain compared to asymptomatic individuals. METHODS: Studies published until February 2024 (without language restrictions) that quantitatively assessed outcomes related to the kinetic chain of non-athlete individuals were searched in five databases (MEDLINE, CINAHL, Web of Science, EMBASE, and SCOPUS). The risk of bias and quality of evidence were analyzed using the Joanna Briggs Institute Critical Appraisal Tool for Analytical Cross-Sectional Studies and the Grading of Recommendations, Assessment, Development, and Evaluation approach, respectively. To summarize the findings, meta-analyses with random-effects models were performed. RESULTS: Six cross-sectional studies (n = 562 [282 with shoulder pain], mean age = 48.7 ± 8.1 years) with low risk of bias were included in this review. Very low-quality evidence suggests that individuals with shoulder pain may present a lower active range of motion and muscular endurance/strength in the cervical spine, thoracolumbar region, and hip, as well as deficits in neuromuscular control of the lower extremities. Findings related to thoracic spine posture were conflicting and no differences were found in cervical spine isometric muscular strength between individuals with and without shoulder pain. CONCLUSION: Individuals with shoulder pain may present alterations in active mobility, muscular endurance, and neuromuscular control in kinetic chain segments. These findings suggest that broader physical assessments considering components of the kinetic chain may be clinically relevant in this population. However, based on the very low quality of evidence, the findings of this review should be interpreted with caution.


Assuntos
Amplitude de Movimento Articular , Dor de Ombro , Humanos , Pessoa de Meia-Idade , Fenômenos Biomecânicos , Estudos Transversais , Cinética , Força Muscular/fisiologia , Amplitude de Movimento Articular/fisiologia , Ombro/fisiopatologia , Dor de Ombro/fisiopatologia , Adulto
9.
Sci Data ; 11(1): 1347, 2024 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-39695251

RESUMO

In Colombia, approximately more than 500.000 people have disabling hearing loss, representing around 1% of the population in Colombia, and only 400 professional interpreters of Colombian Sign Language (LSC) are available in the whole country. In this data descriptor, we present a dataset with recordings of Colombian Sign Language (LSC) as an important effort to develop technologies that facilitate social inclusion and equity for the deaf community in Colombia. This dataset includes multimodal recordings of native and non-native signers signing different elements of the LSC lexicon. In particular, we provide recordings of video and inertial measurement units, along with detected body landmarks and computed information on the inverse kinematics of the upper body such as flexion, extension, and rotation of arms and wrists. This dataset is the first of its kind for LSC and it is key for the development of technologies needed to better understand the language and reduce communication barriers between people with and without hearing loss.


Assuntos
Língua de Sinais , Gravação em Vídeo , Humanos , Colômbia , Perda Auditiva/fisiopatologia , Fenômenos Biomecânicos
10.
Sci Rep ; 14(1): 27291, 2024 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-39516524

RESUMO

The need for strategies to prevent complications from diabetic neuropathy (DPN) is well recognized. However, foot-ankle exercise programs show weak to moderate evidence, and barriers to their implementation persist, including broad and facilitated access to exercise programs, which guarantee for equity. In this paper, we report for the first time the effectiveness of a web-based foot-ankle exercise program aiming to improve DPN-related outcomes, gait biomechanics and functional outcomes. Sixty-two participants with DPN were randomly allocated into the control group (CG; n = 31), which received the usual care, or the intervention group (IG; n = 31), which received the usual care plus a 12-week foot-ankle exercise program using a web-based software (the SOPeD software). The primary outcomes, DPN symptoms and severity, were assessed using the Brazilian version of the Michigan Neuropathy Screening Instrument and the Decision Support System for Classification of Diabetic Polyneuropathy, respectively. Secondary outcomes included tactile sensitivity (monofilaments) and vibration perception (tuning fork), functional outcomes, such as foot pain and function (Foot Health Status Questionnaire), foot muscle strength and plantar pressure during gait (emed plate), and foot-ankle kinematics and kinetics during gait. Outcomes were assessed at baseline, 12 and 24 weeks by an assessor blinded to group allocation. DPN symptoms and severity remained unchanged after the web-based foot-ankle program. However, IG showed improvements compared to CG, with greater functional reach at 12 weeks, better foot function, reduced foot pain and greater plantarflexion degree during push-off at 24 weeks. Regarding plantar loading during gait, the forefoot pressure reduced in the IG at 12 weeks compared to baseline, but at 24 weeks, forefoot load increased in the IG compared to CG. The 12-week web-based foot-ankle exercise program was feasible, acceptable, demonstrating safety with minimal adverse events, such as delayed onset muscle soreness and foot muscle cramping. While DPN-related outcomes were unaffected by the 12-week SOPeD program, modest improvements in foot pain and function, functional reach, and changes in plantar pressure and plantarflexion degree during gait were noted, mostly at 24 weeks.Trial registration: ClinicalTrials.gov, NCT04011267. Registered on 8 July 2019.


Assuntos
Neuropatias Diabéticas , Terapia por Exercício , Humanos , Masculino , Feminino , Neuropatias Diabéticas/terapia , Neuropatias Diabéticas/fisiopatologia , Pessoa de Meia-Idade , Terapia por Exercício/métodos , Idoso , Fatores de Risco , Pé Diabético/terapia , Pé Diabético/fisiopatologia , Marcha/fisiologia , Pé/fisiopatologia , Internet , Resultado do Tratamento , Tornozelo/fisiopatologia , Fenômenos Biomecânicos
11.
Sensors (Basel) ; 24(21)2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39517742

RESUMO

This study introduces an innovative integration of Laban Movement Analysis (LMA) with biomechanical principles to examine the golf swing dynamics from an ecological perspective. Traditionally, LMA focuses on the qualitative aspects of movement, often isolated from external influences. This research bridges that gap by investigating how golfers manage and adapt to the inertial forces of the club throughout the swing. Using motion tracking sensors and screw theory, we analyzed the spatial movement pattern in the Kinesphere (mapped as an icosahedron) and related it to force dynamics in the Effort Cube through the inertia tensor. The results showed significant differences between skilled and novice golfers in terms of how efficiently they align their movements with the club's inertia. Skilled golfers demonstrated smoother Instantaneous Screw Axes (ISAs) and better synchronization with inertia forces, while novice golfers exhibited more abrupt deviations. These findings suggest that integrating qualitative movement descriptors with biomechanical models provides deeper insights into swing efficiency, performance improvement, and injury prevention. This combined framework offers a novel method to enhance both qualitative and quantitative analysis of golf swings.


Assuntos
Golfe , Movimento , Golfe/fisiologia , Humanos , Fenômenos Biomecânicos/fisiologia , Movimento/fisiologia , Masculino , Adulto , Desempenho Atlético/fisiologia
12.
J Electromyogr Kinesiol ; 79: 102948, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39522328

RESUMO

OBJECTIVE: Delayed onset muscle soreness (DOMS) can reduce joint range of motion and strength, cause edema, and increase joint stiffness. Here we set out to determine whether quadriceps DOMS followed by an active recovery low-intensity exercise alters jump landing biomechanics. METHODS: 3D landing kinematics, kinetics, and DOMS were evaluated in 26 healthy adults (15 women) performing drop and vertical jump landings before and after a squat protocol to induce quadriceps DOMS. In the presence of DOMS, half of the participants (n = 13) performed a low-intensity exercise for active recovery (10-minute treadmill walking), while the other half (n = 13) did not. Descriptive statistics and generalized estimative equations were applied to determine the effects of DOMS and active recovery on landing kinematics and kinetics. RESULTS: DOMS decreased knee and ankle flexion angles and increased knee and ankle frontal plane angles during vertical jumps. DOMS elicited a longer time to reach peak ground reaction force during drop jumps. Low-intensity exercise for active recovery reduced DOMS perception but did not alter the biomechanics of landing. CONCLUSION: DOMS changes landing strategy. However, including a low-intensity exercise for active recovery before landing practice did not change the kinematics and kinetics of landing.


Assuntos
Mialgia , Humanos , Feminino , Masculino , Fenômenos Biomecânicos/fisiologia , Mialgia/fisiopatologia , Adulto , Amplitude de Movimento Articular/fisiologia , Articulação do Joelho/fisiologia , Adulto Jovem , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia , Recuperação de Função Fisiológica/fisiologia , Exercício Físico/fisiologia , Articulação do Tornozelo/fisiologia
13.
PLoS One ; 19(11): e0313214, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39541315

RESUMO

Currently available conventional breeding methods for broilers often result in impaired biomechanics and skeletal growth for the animals. The addition of environmental enrichment is an alternative which can help alleviate these effects. This study examines the effects of environmental enrichment on biomechanics, morphometry, and bone mass of broilers across various age groups. In total, 112 Cobb 500 chicks (50% male and 50% female) were used in a completely randomized design experiment, with 56 broilers per treatment (T1 and T2), carried out in subdivided plots. Each plot was subjected to a different treatment, as follows: all plots were subjected to the treatments (T1 = environmental enrichment and T2 = no environment enrichment) and the sub-plots held the broilers' age groups (1, 7, 14, 21, 28, 35 and 42 days old). Eight broilers were euthanized on a weekly basis for two production cycles in order to perform morphometric (diameter and length) and biomechanical analysis of the response variables. These measurements were performed on the femur and tibia. Birds were subjected to classical linear fixed effects model and compared through Tukey's mean test. Significant interactions between environmental enrichment and broiler age were noticed, particularly at 42 days, which displayed bone development for all variables under study. Except for the length of the femur of broiler chickens (p = 0.4638). Therefore, simple effects will not be evaluated. Environmental enrichment had a notable impact on tibia length (p = 0.0035), femur weight (p = 0.0014), and tibia weight (p<0.0001) at 42 days, indicating a favorable effect on skeletal growth in broilers. Enrichment resulted in a 1% increase in femur inertia, a 2% rise in tibia inertia, and a 1% enhancement in ultimate bending stress for both bones, displaying improved structural integrity and durability. Beneficial changes in bone morphology and biomechanics were observed at 42 days after enrichment.


Assuntos
Galinhas , Fêmur , Tíbia , Animais , Galinhas/crescimento & desenvolvimento , Fenômenos Biomecânicos , Feminino , Masculino , Tíbia/fisiologia , Tíbia/crescimento & desenvolvimento , Tíbia/anatomia & histologia , Fêmur/fisiologia , Fêmur/crescimento & desenvolvimento , Fêmur/anatomia & histologia , Meio Ambiente , Locomoção
14.
Braz J Phys Ther ; 28(6): 101136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39541839

RESUMO

BACKGROUND: Interactions between hip and foot biomechanical factors may result in different magnitudes of foot pronation during walking. OBJECTIVE: To investigate non-linear interactions between hip and foot biomechanical factors and their capability to predict foot pronation during walking and identify the profiles of biomechanical factors that predict greater and lower pronation. METHODS: This is a cross-sectional study. Fifty-one women were classified into greater and lower foot pronation during walking. Biomechanical factors measured: (1) foot-ankle varus alignment, (2) hip passive stiffness, (3) isokinetic eccentric strength of hip external rotators, and (4) foot abduction angle. Classification and regression trees (CART) were used to investigate non-linear interactions that predict greater and lower foot pronation. RESULTS: Four main profiles of biomechanical factors were identified as related to greater and lower foot pronation. Profiles for greater pronation were: (1) varus >25.83°; (2) interaction between varus ≤25.83° and hip stiffness ≤0.09 Nm/rad kg-1; (3) interaction between varus ≤25.83°, hip stiffness >0.09 Nm/rad kg-1, and foot abduction >19.58° The profile for lower pronation involved an interaction among varus ≤25.83°, hip stiffness >0.09 Nm/rad kg-1, and foot abduction ≤19.58° The model had 61% sensitivity and 96% specificity, with the total prediction of 78%. The area under the ROC curve was 0.79 (p = 0.001). CONCLUSION: Foot-ankle varus, hip passive stiffness, and foot abduction predicted greater and lower foot pronation. Non-linear interactions between hip and foot factors influence the magnitude of foot pronation during walking. The observed profiles help identify which combinations of biomechanical factors should be assessed in individuals with increased or reduced pronation.


Assuntos
, Pronação , Caminhada , Humanos , Estudos Transversais , Pronação/fisiologia , Pé/fisiologia , Fenômenos Biomecânicos , Caminhada/fisiologia , Feminino , Quadril/fisiologia
15.
BMC Musculoskelet Disord ; 25(1): 885, 2024 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-39506778

RESUMO

Intra-articular fractures of the distal radius require anatomical reduction and stable fixation. When the fracture encompasses the articular facet of the bone, maintaining the reduction is challenging due to the fragment's size and high instability. While specific implants have been developed to fix this fragment, their effectives have been limited. This study evaluates the mechanical performance of a novel hook plate conceived to stabilize the small fragment of the semilunar facet of the radius in non-osteoporotic bones. A simulated lunate facet fracture was created in an adult radius in a virtual model, and a modification of a hook plate was developed using computer-aided design (CAD). Two groups were established for the finite element method (FEM) simulation: a control group (standard plate Medartis™ (Switzerland, A-5500.23) and an angled plate with hooks set at 60º, 90º and 120º. In the FEM simulation, an axial load of 100 N was applied in the Z-axis direction on the fragment. Fracture displacement along the Z axis was more pronounced in the control model (0.32 mm) and less in the angled models, ranging from 0.22 to 0.28 mm. Notably, the plate with a 90° angle showed a more effective reduction in fragment displacement. The distribution of stresses in the system showed the highest levels of stress in the control group (59.31 MPa), followed by the subgroup with a 60° angle (55.78 MPa).In the side view, the control model showed a higher concentration of stresses (59.74 MPa), while the model with a 90° angle showed a lower value of stresses (18.87 MPa). Critical stress regions were identified in the bolts of the control and 120° models (59.47 MPa and 57.64 MPa, respectively). However, in the 90° model, no critical regions were observed in the bolts, which showed lower stress values, reaching 26.33 MPa. In the bone, the greatest concentration of stress occurred in the region where the plate was anchored. Our results showed that the 90° hook plate had a superior mechanical performance in fixing simulate lunate facet fractures at the distal radius. This angle led to minor displacements and minimized stress concentrations in the hardware, thus contributing to enhance the stability of this specific fracture.


Assuntos
Placas Ósseas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Fraturas do Rádio , Humanos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Fraturas do Rádio/cirurgia , Fenômenos Biomecânicos , Adulto , Fraturas Intra-Articulares/cirurgia , Modelos Anatômicos
16.
Head Face Med ; 20(1): 67, 2024 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-39506785

RESUMO

BACKGROUND: The surgical treatment for mandibular repositioning using a bilateral sagittal split osteotomy (BSSO) favours the development of techniques that result in adequate repair and stability. In Puricelli's mandibular sagittal split osteotomy (PMSSO) proposal, the vertical lateral cut osteotomy is located in the interradicular space between the lower first molar and second premolar. OBJECTIVES: This in silico study aimed to investigate the mechanical stability of PMSSO and compare it with the classical Obwegeser-Dal Pont technique for mandibular advancement. MATERIALS AND METHODS: A computational geometric model of the mandible was created in a virtual environment using computer-aided design (CAD) software. After reproducing the advancements, two test groups were developed: GTOD10, Obwegeser-Dal Pont osteotomy, and GTP10, Puricelli osteotomy, both simulating a 10-mm mandibular advancement, allowing for measuring the area of overlap between bone segments. With the geometric changes promoted by the osteotomy, boundary conditions of displacement and force were applied to a CAD software based on finite element analysis (FEA), allowing for quantitative and comparative analysis of the stress and vertical displacement of the mandible, mechanical measurements that may be associated with strength and stiffness. RESULTS: A 17.48% higher stress was observed in the GTP10 group than in GTOD10. However, the region of highest stress in GTP10 was found in a part of the bone that was still intact and far from the area of fragility caused by lateral vertical osteotomy. In contrast, in GTOD10, the region with high stress was in a less resistant bone region. The GTP10 group showed a 28.73% lower displacement than GTOD10. The area of overlap between the proximal and distal segments of the mandible was 33.13% larger in the GTP10 than in the GTOD10 group. CONCLUSION: The PMSSO method, performed in large mandibular advancements, keeps the point of highest stress away from the mandibular fragility zone. Considering the same amount of advancement, it also promotes less displacement and larger areas of bone overlap. CLINICAL RELEVANCE: The results suggest that PMSSO, applied in large mandibular advancement, presents greater postoperative stability.


Assuntos
Análise de Elementos Finitos , Mandíbula , Avanço Mandibular , Osteotomia Sagital do Ramo Mandibular , Humanos , Osteotomia Sagital do Ramo Mandibular/métodos , Fenômenos Biomecânicos , Avanço Mandibular/métodos , Mandíbula/cirurgia , Mandíbula/diagnóstico por imagem , Simulação por Computador , Imageamento Tridimensional , Desenho Assistido por Computador
17.
JMIR Res Protoc ; 13: e57433, 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39496307

RESUMO

BACKGROUND: Wearable technology is widely applied in performance monitoring, an integral part of sports and exercise sciences. The kick movement in soccer exemplifies a sports technique that could benefit from appropriate biomechanics assessment methodologies. However, the accuracy of wearables in quantifying soccer kick mechanics, particularly under field conditions, remains unclear. OBJECTIVE: This study aims to present a protocol for a systematic review to discuss the measurement properties (validity, reliability, and/or accuracy aspects) of wearable technology systems explicitly used to measure ball-kicking features in soccer. METHODS: This review protocol was preregistered in the Open Science Framework. A total of 2 authors will perform searches in major electronic databases using specific keyword combinations in PubMed, Physical Therapy and Sports Medicine, Web of Science, ProQuest, IEEE Xplore, EBSCOHost, and Scopus. Following a specific population, intervention, comparison, outcome framework (population: soccer players and/or collected human data in a football-related environment; intervention: at least 1 wearable used; comparator: criterion measures, repeated testing sessions and/or actual values; outcome: ball kicking data), studies will be screened based on predetermined inclusion and exclusion criteria. The methodological quality of the included studies will be assessed using the "consensus-based standards for the selection of health measurement instruments" checklist (in studies concerning validity or reliability) or the "quality assessment of diagnostic accuracy studies" tool (in studies concerning accuracy). Data extraction will be conducted to determine the level of evidence according to the "best evidence synthesis method," and an evidence gap map will be constructed. The Cohen κ coefficient will be used to estimate the interevaluator agreement. RESULTS: This ongoing systematic review has completed database searches and is currently in the screening phase. Depending on the number and consistency of studies, results may be presented by meta-analysis or qualitative synthesis, with subgroup analyses considering factors such as gender, age, and playing level. The final results are expected by July 2024, with manuscript submission anticipated by November 2024. CONCLUSIONS: Our study will provide a comprehensive summary of the highest level of evidence available on the use of wearables for the assessment of soccer kick mechanics, providing practical guidance for athletes and sports sciences professionals regarding the validity and reliability aspects of using wearable technology to measure ball-kicking features in soccer. TRIAL REGISTRATION: OSF registries https://osf.io/zm3j6. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/57433.


Assuntos
Futebol , Revisões Sistemáticas como Assunto , Dispositivos Eletrônicos Vestíveis , Humanos , Dispositivos Eletrônicos Vestíveis/normas , Reprodutibilidade dos Testes , Fenômenos Biomecânicos
18.
J Bodyw Mov Ther ; 40: 1027-1033, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39593408

RESUMO

OBJECTIVE: Investigate whether wearing 7 mm neoprene knee sleeves during the front squat and box jump CrossFit exercises change the biomechanics of the knee joint. DESIGN: a cross-sectional exploratory study. SETTING: Laboratory-based. PARTICIPANTS: Seventeen male healthy CrossFit participants completed front squats and box jumps with knee sleeves (KS) and without knee sleeves (WKS). MAIN OUTCOMES MEASURES: Kinematic and kinetic data of the knee in the sagittal, frontal and transverse planes were obtained for the two tasks and under the two experimental situations. The maximum load lifted on 1 MR test was recorded under KS and WKS conditions. The GROC scales were applied after each exercise and condition to assess participants' self-reported perception of stability. RESULTS: The KS reduced the knee range of motion in the transverse plane during box jump (p = 0.029) and the peak knee external adduction moment (p = 0.047) during front squat compared to WKS. The 1RM during front squat increased in KS compared to WKS (p < 0.001). Most participants (94%) reported that they felt better stability using KS and all participants (100%) believed that knee sleeves would avoid knee pain. CONCLUSION: neoprene knee sleeves have little impact on the biomechanics of the knee joint during CrossFit. However, participants reported improved knee stability.


Assuntos
Articulação do Joelho , Amplitude de Movimento Articular , Humanos , Masculino , Estudos Transversais , Fenômenos Biomecânicos/fisiologia , Articulação do Joelho/fisiologia , Adulto , Amplitude de Movimento Articular/fisiologia , Neopreno , Adulto Jovem
19.
J Bodyw Mov Ther ; 40: 1508-1513, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39593479

RESUMO

BACKGROUND: Given that people with patellofemoral pain (PFP) exhibit deficits in postural control, certain postural reactions may be associated with movement alterations in this population. Therefore, the objective of the present study was to investigate whether manipulation of the support base for balance maintenance could lead to different patterns of lower limb kinematics in people with PFP during single-legged squats. METHODS: Fourteen participants with PFP and 14 asymptomatic controls were first assessed performing single-legged squats freely, and then while holding a stick to provide stabilization during the task. Center of pressure (CoP) behavior and movements of the hip, knee, ankle in the sagittal, frontal, and transverse planes were evaluated. RESULTS: For the participants with PFP, the use of support led to a reduction in the magnitude of CoP oscillation compared to free squatting, with effect sizes ranging from small to large, but no significant differences were found for the kinematic variables. No significant differences were observed for CoP or kinematic variables in the comparisons between squat conditions in asymptomatic controls. CONCLUSION: In summary, performing single-legged squats in a more stabilized condition did not influence lower limb movements in people with PFP.


Assuntos
Extremidade Inferior , Síndrome da Dor Patelofemoral , Equilíbrio Postural , Humanos , Fenômenos Biomecânicos , Feminino , Masculino , Síndrome da Dor Patelofemoral/fisiopatologia , Síndrome da Dor Patelofemoral/reabilitação , Equilíbrio Postural/fisiologia , Adulto , Adulto Jovem , Extremidade Inferior/fisiopatologia , Movimento/fisiologia
20.
J Bodyw Mov Ther ; 40: 476-481, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39593629

RESUMO

OBJECTIVE: To examine whether musculoskeletal injury history is a factor that influences countermovement jump (CMJ) performance in rugby players and to compare CMJ performance between player's position (forwards or backs). METHODS: Thirty rugby players (15 with an injury history and 15 without an injury history) performed the CMJ using an inertial sensor (Baiobit®) to evaluate kinematic (Jump Height, Velocity and Phase duration) and kinetic data (rate of force development [RFD], impact peak [IP], take-off force and Stiffness]. The group comparison was performed with an independent t-test, and the association between CMJ performance, sociodemographic variables and injury history was investigated with Pearson's correlation test. RESULTS: Rugby players with and without history of musculoskeletal injury differed in age and playing experience, but there was no difference in CMJ performance between groups. Jump height of uninjured players was positively correlated with take-off force and RFD and negatively correlated with concentric phase duration and RFD. Injured players demonstrated a negative correlation between take-off force and IP. Compared to backs, forwards were heavier and taller, showed greater IPs and were more likely to have an injury history. CONCLUSIONS: There were no differences in CMJ performance between rugby players with and without an injury history. Forwards showed greater IPs and were more likelier to have an injury history than backs.


Assuntos
Desempenho Atlético , Futebol Americano , Humanos , Masculino , Fenômenos Biomecânicos/fisiologia , Adulto Jovem , Futebol Americano/lesões , Futebol Americano/fisiologia , Adulto , Desempenho Atlético/fisiologia , Traumatismos em Atletas/fisiopatologia , Força Muscular/fisiologia , Sistema Musculoesquelético/lesões
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