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1.
Sensors (Basel) ; 23(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37299872

RESUMO

A number of textile-based fiber optic sensors have recently been proposed for the continuous monitoring of vital signs. However, some of these sensors are likely unsuitable for conducting direct measurements on the torso as they lack elasticity and are inconvenient. This project provides a novel method for creating a force-sensing smart textile by inlaying four silicone-embedded fiber Bragg grating sensors into a knitted undergarment. The applied force was determined within 3 N after transferring the Bragg wavelength. The results show that the sensors embedded in the silicone membranes achieved enhanced sensitivity to force, as well as flexibility and softness. Additionally, by assessing the degree of FBG response to a range of standardized forces, the linearity (R2) between the shift in the Bragg wavelength and force was found to be above 0.95, with an ICC of 0.97, when tested on a soft surface. Furthermore, the real-time data acquisition could facilitate the adjustment and monitoring of force during the fitting processes, such as in bracing treatment for adolescent idiopathic scoliosis patients. Nevertheless, the optimal bracing pressure has not yet been standardized. This proposed method could help orthotists to adjust the tightness of brace straps and the location of padding in a more scientific and straightforward way. The output of this project could be further extended to determine ideal bracing pressure levels.


Assuntos
Têxteis , Elasticidade , Pressão , Silicones , Reprodutibilidade dos Testes
2.
Sensors (Basel) ; 20(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266213

RESUMO

Flexible force and pressure sensors are important for assessing the wear comfort of tightly fitting apparel. Their accuracy and repeatability depend on the sensor itself and the contacting surface. Measurements of the contact pressure on soft surfaces like human skin tend to be erroneous, which could be due to incorrect sensor calibrations. This study aims to examine the effects of human body parameters such as the hardness and temperature of the contacting surface by using a custom-made calibration setup and investigating the incorporation of rigid discs on the sensor surface. Two commercial force sensors, FlexiForce and SingleTact, and one pressure sensor, Pliance X, are used in the investigation. The findings reveal that adding rigid discs on both sides of the force sensors improves their sensitivity. Systematic calibration has been performed on the surfaces with different temperatures and hardness. The results show that FlexiForce and Pliance X tend to be affected by the changes in surface temperature and surface hardness. Prolonged testing time shows that the time dependence of SingleTact and Pliance X sensor is lower, which suggests that they are more suitable for lengthier evaluations in which interface pressure is exerted on the human body. In brief, sensor attachment and proper calibration should be thoroughly considered before using sensors for applications on soft surfaces, like the human body.

3.
Hum Factors ; 61(8): 1247-1260, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30950640

RESUMO

OBJECTIVE: The objective of this study is to evaluate the efficacy of indoor footwear with a textured surface to improve control of balance and reduce excessive plantar pressure in older women. BACKGROUND: Balance instability is a common condition in older people. Textured insoles with protrusions on the entire insole have been examined for enhancing somatosensory feedback in the elderly to improve control over balance. However, these insoles have significant challenges in distributing the plantar pressure. Textured insoles with tailored protrusions should be therefore investigated for the same purpose but provide better plantar pressure distribution. METHOD: A total of 24 older women have undergone both static standing and walking tests with the use of the in-shoe Pedar® system. RESULTS: The results indicate that wearing textured indoor footwear provides a significant reduction in postural sway, particularly in the medial-lateral direction during walking. As compared to walking barefoot, the center-of-pressure trajectory when wearing the textured indoor footwear remains supported with less variance among the steps, which is statistically significant in the medial-lateral direction. A significant reduction in the peak pressure is found in the forefoot and rearfoot regions as the plantar pressure is redistributed to the midfoot regions. CONCLUSION: The textured surface of the insole improves balance control of older women and effectively reduces foot pressure at high pressure areas. APPLICATION: The findings enhance current understanding on textured footwear as a form of intervention associated with changes in functional impairments, therefore providing basis for footwear design in balance control.


Assuntos
Envelhecimento/fisiologia , Equilíbrio Postural/fisiologia , Equipamentos de Proteção , Sapatos , Posição Ortostática , Caminhada/fisiologia , Idoso , Fenômenos Biomecânicos , Feminino , Humanos
4.
J Aging Phys Act ; 25(4): 587-595, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28253060

RESUMO

Indoor slippers with a strap across the dorsal forefoot are popular with older women. However, their influence on the foot motion has not been reported. This study evaluated the range of movement in the knee and ankle joints during walking and changes in trunk displacement during sit-to-stand when 10 healthy older women wore two types of slippers and were barefoot. Compared to barefeet, walking in slippers results in significant increases in the knee flexion angle in the swing phase. However, there is nonsignificant differences in the ankle angle in any phase across all conditions. During the sit-stand transition when slippers are worn, there is a significant reduction in the peak trunk tilt angle and range, as well as the duration of the weight shift when motion is initiated. The findings therefore provide a better understanding of slipper features and designs associated with changes in foot kinematics in older women.


Assuntos
Articulação do Tornozelo/fisiopatologia , Articulação do Joelho/fisiopatologia , Sapatos , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Movimento/fisiologia , Postura/fisiologia , Amplitude de Movimento Articular , Sapatos/efeitos adversos , Sapatos/normas , Caminhada/fisiologia
5.
Ergonomics ; 60(6): 876-886, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27547883

RESUMO

Adolescent idiopathic scoliosis is a common condition found in adolescents. A rigid brace is often prescribed as the treatment for this spinal deformity, which negatively affects user compliance due to the discomfort caused by the brace, and the psychological distress resulting from its appearance. However, the latter, which is the impact of visual aesthetics, has not been thoroughly studied for scoliosis braces. Therefore, a qualitative study with in-depth interviews has been carried out with 10 participants who have a Cobb angle of 20°-30° to determine the impact of visual aesthetics on user acceptance and compliance towards the brace. It is found that co-designing with patients on the aesthetic aspects of the surface design of the brace increases the level of user compliance and induces positive user perception. Therefore, aesthetic preferences need to be taken into consideration in the design process of braces. Practitioner Summary: The impact of visual aesthetics on user acceptance and compliance towards a rigid brace for scoliosis is investigated. The findings indicate that an aesthetically pleasing brace and the involvement of patients in the design process of the brace are important for increasing user compliance and addressing psychological issues during treatment.


Assuntos
Braquetes , Desenho de Equipamento/psicologia , Estética/psicologia , Cooperação do Paciente/psicologia , Escoliose/psicologia , Adolescente , Criança , Feminino , Humanos , Pesquisa Qualitativa , Escoliose/terapia , Adulto Jovem
6.
Biomech Model Mechanobiol ; 23(5): 1679-1694, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38806750

RESUMO

This study aims to investigate the biomechanical behaviour and the stiffness impact of the breast internal components during running. To achieve this, a novel nonlinear multi-component dynamic finite element method (FEM) has been established, which uses experimental data obtained via 4D scanning technology and a motion capture system. The data are used to construct a geometric model that comprises the rigid body, layers of soft tissues, skin, pectoralis major muscle, fat, ligaments and glandular tissues. The traditional point-to-point method has a relative mean absolute error of less than 7.92% while the latest surface-to-surface method has an average Euclidean distance (d) of 7.05 mm, validating the simulated results. After simulating the motion of the different components of the breasts, the displacement analysis confirms that when the motion reaches the moment of largest displacement, the displacement of the breast components is proportional to their distance from the chest wall. A biomechanical analysis indicates that the stress sustained by the breast components in ascending order is the glandular tissues, pectoralis major muscle, adipose tissues, and ligaments. The ligaments provide the primary support during motion, followed by the pectoralis major muscle. In addition, specific stress points of the breast components are identified. The stiffness impact experiment indicates that compared with ligaments, the change of glandular tissue stiffness had a slightly more obvious effect on the breast surface. The findings serve as a valuable reference for the medical field and sports bra industry to enhance breast protection during motion.


Assuntos
Mama , Análise de Elementos Finitos , Corrida , Estresse Mecânico , Humanos , Mama/fisiologia , Fenômenos Biomecânicos , Corrida/fisiologia , Feminino , Modelos Biológicos , Simulação por Computador
7.
PLoS One ; 19(2): e0299040, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38408041

RESUMO

Understanding the dynamic deformation pattern and biomechanical properties of breasts is crucial in various fields, including designing ergonomic bras and customized prostheses, as well as in clinical practice. Previous studies have recorded and analyzed the dynamic behaviors of the breast surface using 4D scanning, which provides a sequence of 3D meshes during movement with high spatial and temporal resolutions. However, these studies are limited by the lack of robust and automated data processing methods which result in limited data coverage or error-prone analysis results. To address this issue, we identify revealing inter-frame dense correspondence as the core challenge towards conducting reliable and consistent analysis of the 4D scanning data. We proposed a fully-automatic approach named Ulta-dense Motion Capture (UdMC) using Thin-plate Spline (TPS) to augment the sparse landmarks recorded via motion capture (MoCap) as initial dense correspondence and then rectified it with a sophisticated post-alignment scheme. Two downstream tasks are demonstrated to validate its applicability: virtual landmark tracking and deformation intensity analysis. For evaluation, a dynamic 4D human breast anthropometric dataset DynaBreastLite was constructed. The results show that our approach can robustly capture the dynamic deformation characteristics of the breast surfaces, significantly outperforms baselines adapted from previous works in terms of accuracy, consistency, and efficiency. For 10 fps dataset, average error of 0.25 cm on control-landmarks and 0.33 cm on non-control (arbitrary) landmarks were achieved, with 17-70 times faster computation time. Evaluation was also carried out on 60 fps and 120 fps datasets, with consistent and large performance gaining being observed. The proposed method may contribute to advancing research in breast anthropometry, biomechanics, and ergonomics by enabling more accurate tracking of the breast surface deformation patterns and dynamic characteristics.


Assuntos
Captura de Movimento , Movimento , Humanos , Movimento (Física) , Tórax
8.
Materials (Basel) ; 17(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38541593

RESUMO

Conventional cushioning materials such as silicone sheets which have been recommended for resisting impact generally cause discomfort to the wearer from heat and perspiration. With the increasing need for personal protective equipment, textile-silicone composite structures are proposed in this study to reduce acute impact and moisture while enhancing thermal comfort. The influence of the composite structure and thickness on the mechanical and thermal properties of textile-silicone materials are systematically investigated. The results show that an additional knitted powernet fabric as a composite material can significantly improve the tensile properties of silicone rubber by up to 315%. However, only a slight improvement is found in the thermal conductivity (up to 16%), compression elasticity (up to 18%) and force reduction performance (up to 3.6%). As compared to inlaid spacer fabric, which has also been used for cushioning and preserving thermal comfort, the textile-silicone composites have higher tensile and compression elasticity, exhibit force reduction with the largest difference of 43% and are more thermally conductive, with increases more than 38%. The findings of this study introduced a cost-effective new silicone-textile composite for optimal impact protection and wear comfort for protective applications.

9.
Bioengineering (Basel) ; 10(11)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38002430

RESUMO

The foot, as the foundation of the human body, bears the vast majority of the body's weight. Obese children bear more weight than healthy children in the process of walking and running. This study compared three footwear midsole structures (solid, lattice, and chiral) based on plantar pressure distribution and bone stress in obese and healthy children through numerical simulation. The preparation for the study included obtaining a thin-slice CT scan of a healthy 9-year-old boy's right foot, and this study distinguished between a healthy and an obese child by applying external loadings of 25 kg and 50 kg in the finite element models. The simulation results showed that the plantar pressure was mainly concentrated in the forefoot and heel due to the distribution of gravity (first metatarsal, fourth metatarsal, and heel bone, corresponding to plantar regions M1, M4, and HM and HL) on the foot in normal standing. Compared with the lattice and solid EVA structures, in both healthy and obese children, the percentage reduction in plantar pressure due to the chiral structure in the areas M1, M4, HM, and HL was the largest with values of 38.69%, 34.25%, 64.24%, and 54.03% for an obese child and 33.99%, 28.25%, 56.08%, and 56.96% for a healthy child. On the other hand, higher pressures (15.19 kPa for an obese child and 5.42 kPa for a healthy child) were observed in the MF area when using the chiral structure than when using the other two structures, which means that this structure can transfer an amount of pressure from the heel to the arch, resulting in a release in the pressure at the heel region and providing support at the arch. In addition, the study found that the chiral structure was not highly sensitive to the external application of body weight. This indicates that the chiral structure is more stable than the other two structures and is minimally affected by changes in external conditions. The findings in this research lay the groundwork for clinical prevention and intervention in foot disorders in obese children and provide new research ideas for shoe midsole manufacturers.

10.
Bioengineering (Basel) ; 10(10)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37892868

RESUMO

This study aims to highlight recent research work on topics around prosthetic feet through a scientometric analysis and historical review. The most cited publications from the Clarivate Analytics Web of Science Core Collection database were identified and analyzed from 1 January 2000 to 31 October 2022. Original articles, reviews with full manuscripts, conference proceedings, early access documents, and meeting abstracts were included. A scientometric visualization analysis of the bibliometric information related to the publications, including the countries, institutions, journals, references, and keywords, was conducted. A total of 1827 publications met the search criteria in this study. The related publications grouped by year show an overall trend of increase during the two decades from 2000 to 2022. The United States is ranked first in terms of overall influence in this field (n = 774). The Northwestern University has published the most papers on prosthetic feet (n = 84). Prosthetics and Orthotics International has published the largest number of studies on prosthetic feet (n = 151). During recent years, a number of studies with citation bursts and burst keywords (e.g., diabetes, gait, pain, and sensor) have provided clues on the hotspots of prosthetic feet and prosthetic foot trends. The findings of this study are based on a comprehensive analysis of the literature and highlight the research topics on prosthetic feet that have been primarily explored. The data provide guidance to clinicians and researchers to further studies in this field.

11.
Artigo em Inglês | MEDLINE | ID: mdl-36834384

RESUMO

Official guidelines state that suitable physical activity is recommended for patients with diabetes mellitus. However, since walking at a rapid pace could be associated with increased plantar pressure and potential foot pain, the footwear condition is particularly important for optimal foot protection in order to reduce the risk of tissue injury and ulceration of diabetic patients. This study aims to analyze foot deformation and plantar pressure distribution at three different walking speeds (slow, normal, and fast walking) in dynamic situations. The dynamic foot shape of 19 female diabetic patients at three walking speeds is obtained by using a novel 4D foot scanning system. Their plantar pressure distributions at the three walking speeds are also measured by using the Pedar in-shoe system. The pressure changes in the toes, metatarsal heads, medial and lateral midfoot, and heel areas are systematically investigated. Although a faster walking speed shows slightly larger foot measurements than the two other walking speeds, the difference is insignificant. The foot measurement changes at the forefoot and heel areas, such as the toe angles and heel width, are found to increase more readily than the measurements at the midfoot. The mean peak plantar pressure shows a significant increase at a faster walking speed with the exception of the midfoot, especially at the forefoot and heel areas. However, the pressure time integral decreases for all of the foot regions with an increase in walking speed. Suitable offloading devices are essential for diabetic patients, particularly during brisk walking. Design features such as medial arch support, wide toe box, and suitable insole material for specific area of the foot (such as polyurethane for forefoot area and ethylene-vinyl acetate for heel area) are essential for diabetic insole/footwear to provide optimal fit and offloading. The findings contribute to enhancing the understanding of foot shape deformation and plantar pressure changes during dynamic situations, thus facilitating the design of footwear/insoles with optimal fit, wear comfort, and foot protection for diabetic patients.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Feminino , Velocidade de Caminhada , , Caminhada , Calcanhar
12.
Sci Rep ; 13(1): 8628, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37244970

RESUMO

Accurate and reliable foot measurements at different stances offer comprehensive geometrical information on foot, thus enabling a more comfortable insole/footwear for practical use and daily activities. However, there lacks investigations on continuous deformation of foot shape during the roll-over process. This study analyses the foot deformation of 19 female diabetic patients during half weight bearing standing and self-selected walking speed by using a novel 4D foot scanning system. The scanning system has good repeatability and accuracy in both static and dynamic scanning situations. Point cloud registration for scanned image reorientation and algorithms to automatically extract foot measurements is developed. During the foot roll-over process, maximum deformation of length and girth dimensions are found at first toe contact. Width dimensions have maximum deformation at heel take off. The findings provide a new understanding of foot shape changes in dynamic situations, thus providing an optimal solution for foot comfort, function and protection.


Assuntos
, Calcanhar , Humanos , Feminino , Pé/diagnóstico por imagem , Suporte de Carga , Sapatos , Algoritmos , Caminhada
13.
Appl Ergon ; 104: 103803, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35635942

RESUMO

Traditional insole materials which trap heat and moisture inside footwear cause discomfort to the wearer. Here, a novel textile-fabricated insole material with a 3D structure that offers good porosity and breathability for improving the footwear microclimate is proposed. Changes in foot skin temperature and humidity when wearing the textile-fabricated insole throughout treadmill walking are collected from 21 female subjects (age: 25.5 ± 4.5) and compared with traditional and 3D printed insoles. Subjective assessment of their perceived thermal comfort with various insole conditions is also conducted. In comparison to polyurethane, 3D printed thermoplastic polyurethane and leather insoles, textile-fabricated insoles show no significant changes in foot skin temperature. Nevertheless, a significant reduction of the relative humidity of the skin of the sole (3.21%) and heel (24.41%) is found. The findings are a valuable reference for the fabrication of insoles with higher wear comfort.


Assuntos
Órtoses do Pé , Temperatura Cutânea , Adulto , Desenho de Equipamento , Feminino , Humanos , Umidade , Poliuretanos , Sapatos , Têxteis , Adulto Jovem
14.
Polymers (Basel) ; 14(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35160608

RESUMO

Insoles provide resistance to ground reaction forces and comfort during walking. In this study, a novel weft-knitted spacer fabric structure with inlays for insoles is proposed which not only absorbs shock and resists pressure, but also allows heat dissipation for enhanced thermal comfort. The results show that the inlay density and spacer yarn increase compression resistance and reduce impact forces. The increased spacer yarn density provides better air permeability but reduces thermal resistance, while a lower inlay density with a random orientation reduces the evaporative resistance. The proposed structure has significantly positive implications for insole applications.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36078575

RESUMO

Studying the in-shoe microclimate of older individuals is important for enhancing their foot comfort and preventing foot diseases. However, there is a lack of scientific work that explores the thermo-physiological wear comfort of older individuals with different footwear. This study aims to examine the effects of upper footwear materials on changes and distributions in the foot skin temperature and relative humidity for older individuals. Forty older individuals are recruited to perform sitting and walking activities under four experimental conditions in a conditioning chamber. The findings indicate that footwear upper constructed of highly permeable mesh fabric with large air holes shows fewer changes in foot skin temperature (ranging from 1.3 to 3.3 °C) and relative humidity (ranging from -13.3 to 5.7%) throughout the entire foot during dynamic walking, as well as higher subjective ratings on perceived thermal comfort when compared to footwear made of synthetic leather and composite layers. The findings serve to enhance current understanding of designing footwear with optimum comfort for older adults.


Assuntos
, Temperatura Cutânea , Idoso , Pé/fisiologia , Humanos , Umidade , Sapatos , Temperatura
16.
Artigo em Inglês | MEDLINE | ID: mdl-36497840

RESUMO

Sports bras are an essential apparel for active women, but may exert excessive pressure that negatively affects thermoregulation, thermal comfort and wear sensation. This study measures skin temperature changes during short durations of exercise on a treadmill with different bra pressures. The results based on 21 female subjects (age: 27.2 ± 4.5 years old) show that bras with more pressure at the underband or shoulder straps do not cause statistically significant skin temperature changes during exercise (p > 0.05). Nevertheless, compared to the optimal bra fit, significant differences in bra-breast skin temperature are found during running, cooling down and sitting when the bra pressure is increased (p < 0.05), particularly under bra cup (T1) in this study. The FLIR thermal images can visualize the skin temperature changes at abdomen throughout the four activity stages. Subjective sensations of bra thermal comfort, pressure and breast support are assessed. Despite the increased pressure on the shoulders and chest wall, perceptions towards thermal comfort remain unchanged. The perceived pressure comfort and support sensation amongst the 4 bra conditions are comparable. Interestingly, positive sensations of pressure comfort and breast support are perceived with a tight-fitting sports bra during treadmill exercise. High pressures induced by sports bras (>4 kPa) that habitually considered harmful to the human body may not lead to wear discomfort but enhance bra support sensation and a sense of security to the wearers.


Assuntos
Corrida , Temperatura Cutânea , Feminino , Humanos , Adulto Jovem , Adulto , Vestuário , Corrida/fisiologia , Mama , Teste de Esforço , Regulação da Temperatura Corporal
17.
Sci Rep ; 12(1): 15395, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100637

RESUMO

To investigate the effect of contoured insoles constructed of different insole materials, including Nora Lunalastik EVA, Nora Lunalight A fresh, Pe-Lite, and PORON Medical 4708 with Langer Biomechanics longitudinal PPT arch pads on offloading plantar pressure on the foot of the elderly with Type 1 or 2 diabetes during gait. Twenty-two elderly with Type 1 or 2 diabetes participated in the study. Their plantar pressure was measured by using an insole measurement system, while the participants walked 10 m in their bare feet or used each experimental insole in random order. The plantar surface was divided into four specific regions including the toes, forefoot, midfoot, and rearfoot. The mean peak pressure (MPP) and pressure-time integral (PTI) of ten steps with or without wearing one of the four insoles were analyzed on the dominant foot and the four specific plantar regions. After completion of the activities, the participants scored each insole from 1 (the least comfortable) to 10 (the most comfortable). The analysis of variance (ANOVA) factor of the insoles had significant effects on the MPP (P < 0.001) and PTI (P = 0.004) in the dominant foot during gait. Pairwise comparison results showed that the MPP and PTI in the dominant foot were significantly lower (P < 0.001) with PORON Medical 4708 than barefoot, Nora Lunalight A fresh, and Pe-Lite. Additionally, the insole materials had a significant effect for the forefoot (P < 0.001) and rearfoot (P < 0.001) in terms of the MPP and PTI compared with the barefoot condition during gait. Regardless of the plantar region, the MPP and PTI values were the lowest when PORON Medical 4708 was used as the insole material among four insole materials. Meanwhile, a significantly lower MPP and PTI can be found in the forefoot and rearfoot with the use of the four experimental insoles when compared with barefoot. The soft insole materials (i.e., PORON medical 4708 and Nora Lunalastik EVA) had a better performance than the rigid insole materials (i.e., Nora Lunalight A fresh, and Pe-Lite) on plantar pressure offloading for diabetic elderly.


Assuntos
Diabetes Mellitus , Sapatos , Idoso , , Marcha , Humanos , Pressão
18.
Comput Biol Med ; 146: 105582, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35588678

RESUMO

More than 422 million people worldwide suffered from diabetes mellitus (DM) in 2021. Diabetic foot is one the most critical complications resultant of DM. Foot ulceration and infection are frequently arisen, which are associated with changes in the mechanical properties of the plantar soft tissues, peripheral arterial disease, and sensory neuropathy. Diabetic insoles are currently the mainstay in reducing the risk of foot ulcers by reducing the magnitude of the pressure on the plantar Here, we propose a novel pressure relieving heel pad based on a circular auxetic re-entrant honeycomb structure by using three-dimensional (3D) printing technology to minimize the pressure on the heel, thus reducing the occurrence of foot ulcers. Finite element models (FEMs) are developed to evaluate the structural changes of the developed circular auxetic structure upon exertion of compressive forces. Moreover, the effects of the internal angle of the re-entrant structure on the peak contact force and the mean pressure acting on the heel as well as the contact area between the heel and the pads are investigated through a finite element analysis (FEA). Based on the result from the validated FEMs, the proposed heel pad with an auxetic structure demonstrates a distinct reduction in the peak contact force (∼10%) and the mean pressure (∼14%) in comparison to a conventional diabetic insole (PU foam). The characterized result of the designed circular auxetic structure not only provides new insights into diabetic foot protection, but also the design and development of various impact resistance products.


Assuntos
Diabetes Mellitus , Pé Diabético , Neuropatias Diabéticas , Diabetes Mellitus/terapia , Pé Diabético/terapia , Análise de Elementos Finitos , Calcanhar , Humanos , Impressão Tridimensional , Sapatos
19.
Artigo em Inglês | MEDLINE | ID: mdl-36231798

RESUMO

BACKGROUND: Alterations in the lower limb kinematics and kinetics of diabetic patients have been reported in previous studies. Inappropriate choices of orthopedic insole materials, however, fail to prevent diabetic foot ulcers and modify abnormal gait. The aim of this study was to quantitatively compare the effects of contoured insoles with different materials on the kinematics of and kinetics changes in the diabetic elderly during gait. METHODS: There were 21 diabetic patients who participated in this study. Three-dimensional (3D) experimental contoured insoles constructed of soft (i.e., Nora Lunalastik EVA and PORON® Medical 4708) and rigid (i.e., Nora Lunalight A fresh and Pe-Lite) materials with Langer Biomechanics longitudinal PPT® arch pads were adopted. An eight-camera motion capture system (VICON), two force plates, and an insole measurement system-Pedar® with 99 sensors-were utilized to obtain the kinematics and kinetics data. The plug-in lower body gait model landmarks were used for dynamic data acquisition during gait. The corresponding data from five gait cycles were selected and calculated. RESULTS: The range of motions (ROMs) of the ankle joint (p = 0.001) and knee joint (p = 0.044) were significantly influenced when the contoured insoles were worn in comparison to the barefoot condition. The joint moments of the lower limbs with maximum ankle plantarflexion during the loading response and maximum knee and hip flexions were significantly influenced by the use of contoured insoles with different materials in the diabetic elderly. The peak plantar pressure (PPP) of the forefoot (p < 0.001), midfoot (p = 0.009), and rearfoot (p < 0.001) was significantly offloaded by the contoured insoles during the stance phase, whilst the PPP of the rearfoot (p < 0.001) was significantly offloaded during the swing phase. CONCLUSIONS: The contoured insoles, especially those constructed with soft materials, significantly offloaded the PPP during gait-hence accommodating certain abnormal gait patterns more effectively compared to going barefoot.


Assuntos
Diabetes Mellitus , Pé Diabético , Órtoses do Pé , Idoso , Fenômenos Biomecânicos/fisiologia , Pé Diabético/prevenção & controle , Marcha/fisiologia , Humanos , Cinética , Caminhada/fisiologia
20.
PLoS One ; 17(3): e0264233, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35320281

RESUMO

In-depth analyses of foot surface measurements upon weight bearing are crucial to understand how the dorsal and plantar surfaces of the foot deform during motion to enhance the fit of footwear, which is particularly important for diabetic patients with stringent fit requirements to redistribute the plantar weight forces. This study analyzes diabetic foot deformations under 3 different weight bearing conditions (no weight bearing, half weight bearing, and 80% weight bearing) by using a novel foot scanning method that enables efficient scanning of the dorsal and plantar surfaces of the foot simultaneously. The feet of 48 patients with diabetes mellitus (DM) are scanned. With increased load on the feet, the width of the forefoot increases by 9.7%-10.4%, height of the midfoot decreases by 15.1%-18.2%, forefoot and midfoot rotate to the medial side by 16.9%-23.9% while the rearfoot rotates to the lateral side by 15.2% simultaneously, and the plantar of the foot increases contact with the floor by 11.4%-23.0%. Gender differences in foot shape are also found between males and females, males have a broader foot than females for the same foot length. Precise anthropometric information of foot changes and deformation therefore enables adequate foot protection, fit and comfort when designing footwear. This research contributes to shoe design considerations that focus on the deformation of the foot under different loads.


Assuntos
Diabetes Mellitus , Pé Diabético , Fenômenos Biomecânicos , Feminino , , Humanos , Masculino , Sapatos , Caminhada , Suporte de Carga
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