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1.
Hum Mov Sci ; 68: 102524, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31733429

RESUMO

In computational models of human walking, both magnitude and timing of locomotor propulsion are important for mechanical and metabolic efficiency, suggesting that these are likely tightly controlled by the neuromuscular system. Studies of actual human walking have focused primarily on magnitude-related measures of propulsion, often ignoring its timing. The purpose of this study was to quantify the timing of onset and peak propulsion relative to contralateral heel strike (HS) in healthy, young adults walking at multiple speeds. Propulsion was quantified at the ground-level using the anterior component of the anteroposterior ground reaction force, the limb-level using individual limb power, and the joint-level using ankle power. Contrary to common computational models, most of our timing-related measures indicated that propulsion occurred after contralateral HS. Timing-related measures of propulsion also changed with walking speed - as speed increased, individuals initiated propulsion earlier in the support phase. Timing of locomotor propulsion is theoretically important for walking performance, especially metabolic efficiency, and could therefore provide important clinical information. This study provides a set of relatively simple metrics that can be used to quantify propulsion and benchmark data that can be used for future comparisons with individuals or populations with gait impairments.


Assuntos
Caminhada/fisiologia , Adulto , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos/fisiologia , Teste de Esforço/métodos , Feminino , Calcanhar/fisiologia , Humanos , Masculino , Velocidade de Caminhada/fisiologia , Adulto Jovem
2.
Gait Posture ; 74: 212-217, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31561119

RESUMO

BACKGROUND: A growing body of literature supports the promising effect of real-time feedback to re-train runners. However, no studies have comprehensively assessed the effects of foots trike and cadence modification using different forms of real-time feedback provided via wearable devices. RESEARCH QUESTION: The purpose of the present study was to determine if a change could be made in foot strike pattern and plantar loads using real-time visual, auditory and combined feedback provided using wearable devices. METHODS: Visual, auditory and combined feedback were provided using wearable devices as fifteen recreational runners ran on a treadmill at self-selected speed and increased cadence. Plantar loads and location of initial contact were measured with a flexible insole system. Repeated measures ANOVAs with Bonferroni adjusted pair-wise comparisons were used to assess statistical significance. RESULTS AND SIGNIFICANCE: A significant effect of condition was noted on location of center of pressure (p < 0.01). Bonferroni-adjusted post-hoc comparisons showed that feedback conditions differed from baseline as well as the new cadence conditions, however did not differ from each other. A significant interaction effect (region x feedback) was found for plantar loads (maximum force P < 0.001). Significant effects of feedback were noted at the heel (P < 0.001), medial midfoot (P < 0.001), lateral midfoot (P < 0.001), medial forefoot (P = 0.003), central forefoot (P = 0.003), and great toe (P = 0.004) but not at the lateral forefoot (P = 0.6) or lateral toes (P = 0.507). SIGNIFICANCE: The unique findings of our study showed that an anterior shift of the center of pressure, particularly when foot strike modification was combined with 10% increased cadence. We found lower heel and midfoot loads along with higher forefoot and great toe loads when foot strike modification using real-time feedback was combined with increased cadence. Our findings also suggest that auditory feedback might be more effective than visual feedback in foot-strike modification.


Assuntos
Pé/fisiologia , Feedback Formativo , Corrida/fisiologia , Dispositivos Eletrônicos Vestíveis , Suporte de Carga/fisiologia , Adulto , Análise de Variância , Teste de Esforço , Feminino , Calcanhar/fisiologia , Humanos , Masculino , Atividade Motora/fisiologia , Sapatos , Dedos do Pé/fisiologia , Adulto Jovem
3.
J Sports Sci ; 37(21): 2475-2482, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31311452

RESUMO

Previous research suggests that landing mechanics may be affected by the mechanics of the preceding jump take-off. The purpose of the present study was to investigate whether jump take-off mechanics influence the subsequent landing mechanics. Female volleyball (n = 17) and ice hockey (n = 19) players performed maximal vertical jumps with forefoot and heel take-off strategies. During forefoot and heel jumps, participants were instructed to shift their weight to their forefoot or heel, respectively, and push through this portion of the foot throughout the jump. Jump mechanics were examined using 3D motion analysis, where lower extremity net joint moment (NJM) work, NJM, and segment angles were compared between forefoot and heel jumps using multivariate ANOVA. During jump take-off, participants performed more positive ankle plantar flexor and knee extensor NJM work in forefoot compared to heel jumps (P < 0.05). From initial foot contact to foot flat, participants performed more negative ankle plantar flexor and hip extensor NJM work during heel compared to forefoot jumps (P < 0.05). The present results demonstrate that using a heel take-off strategy results in a different distribution of lower extremity NJM work and NJM during landing compared to landings following forefoot jumps.


Assuntos
Pé/fisiologia , Calcanhar/fisiologia , Extremidade Inferior/fisiologia , Exercício Pliométrico , Adolescente , Tornozelo/fisiologia , Fenômenos Biomecânicos , Feminino , Hóquei/fisiologia , Humanos , Joelho/fisiologia , Estudos de Tempo e Movimento , Voleibol/fisiologia , Adulto Jovem
4.
Med Sci Sports Exerc ; 51(8): 1692-1697, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30817717

RESUMO

PURPOSE: High vertical ground reaction force (vGRF) loading rates are thought to contribute to lower extremity injuries in runners. Given that elevated lower extremity stiffness has been reported to be associated with increased GRFs, the purpose of the current study was to determine if overall lower extremity stiffness, individual joint angular excursions and/or torsional stiffness are predictive of the average vGRF loading rate during running. METHODS: Forty heel strike runners (20 men and 20 women) ran overground at a speed of 3.4 m·s. Average vGRF loading rate, lower extremity stiffness, and hip, knee, and ankle joint excursions and torsional stiffness from initial contact to the first peak of the vGRF were quantified. Stepwise multiple linear regression was performed to determine the best predictor(s) of average vGRF loading rate. RESULTS: Lower extremity stiffness was found to the best predictor of average vGRF loading rate (R = 0.68, P < 0.001). The second variable that entered the stepwise regression model of average vGRF loading rate was knee joint excursion (ΔR = 0.03, P = 0.023). CONCLUSIONS: Increased lower extremity stiffness immediately after initial contact may expose heel strike runners to higher vGRF loading rates.


Assuntos
Marcha/fisiologia , Extremidade Inferior/fisiologia , Corrida/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Calcanhar/fisiologia , Humanos , Extremidade Inferior/lesões , Masculino , Fatores de Risco , Corrida/lesões , Estresse Mecânico , Adulto Jovem
5.
Gait Posture ; 69: 224-234, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30870745

RESUMO

BACKGROUND: Heel lifts, placed inside footwear are recommended for the management of numerous musculoskeletal conditions. Despite the potential therapeutic benefit of heel lifts, the mechanism(s) by which they exert their effects is unclear. The aim of this systematic review was to synthesise reported findings and summarise the effects of heel lifts on lower limb biomechanics and muscle function. RESEARCH QUESTION: Do heel lifts affect lower limb biomechanics and muscle function during walking and running? METHODS: Electronic databases (MEDLINE, EMBASE, CINAHL, SPORTDiscus, AMED) were searched from inception to April 2018. Studies were included if they (i) included participants without a limb length discrepancy or neurological condition, (ii) evaluated the effect of bilateral heel lifts that were removable (attached to the participants' foot (barefoot) or inserted inside footwear) or an existing feature of a shoe, and (iii) assessed lower limb biomechanics or muscle function during walking or running in asymptomatic or symptomatic participants. RESULTS: A total of 23 studies (377 participants) were included. Study quality, assessed using a Modified Quality Index, ranged from 5 to 13 out of 15. A large number of biomechanical parameters were assessed, but few effects were statistically significant. The differences that were significant and had a large effect size are described below. In asymptomatic participants, heel lifts of 10 mm decreased duration of swing phase (standardised mean difference [SMD] = -1.3) and heel lifts of at least 5 cm decreased velocity (SMD = -0.93) during walking. In asymptomatic participants, heel lifts of 15 mm decreased maximum ankle dorsiflexion angle (SMD = -1.5) and heel lifts of 12 and 18 mm decreased gastrocnemius muscle tendon unit length (SMD = -0.96) during running. In participants with restricted ankle joint dorsiflexion, heel lifts of 6 and 9 mm increased medial gastrocnemius electromyography amplitude (SMD between 0.68 and 0.98) during walking. In participants with haemophilia, heel lifts of 9 mm increased ankle joint maximum range of motion (SMD = 1.6) during walking. SIGNIFICANCE: Heel lifts affect specific lower limb biomechanical and muscle function parameters during walking and running. The clinical relevance and potential therapeutic benefits of these effects needs further investigation.


Assuntos
Órtoses do Pé , Extremidade Inferior/fisiologia , Músculo Esquelético/fisiologia , Corrida/fisiologia , Caminhada/fisiologia , Fenômenos Biomecânicos , Calcanhar/fisiologia , Humanos , Amplitude de Movimento Articular
6.
J Sports Sci ; 37(14): 1582-1590, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30747038

RESUMO

Biomechanical differences in double poling (DP) between sex and performance level were investigated in female and male cross-country skiers during a classical race (10/15 km). Skiers were divided into faster and slower on basis of race performance: females faster (n=20), females slower (n=20), males faster (n=20), and males slower (n=20). Based on video analysis while DP in a flat section of the track, joint and pole angles at pole plant (PP) and pole-off, cycle characteristics and the use and coordination pattern of heel-raise (raise of heels from the ground to have a higher body position at PP) were analysed. Faster females and males had 4.3% and 7.8% higher DP velocity than their slower counterparts (both P<0.001). Faster males had 6.5% longer cycles than slower males (P<0.001). Faster skiers stopped heel-raise later than slower skiers (females: 2.0±3.4% vs. -1.0±3.5%, P<0.05; males: 3.9±2.4% vs. 0.8±3.2% of cycle time in relation to PP, P<0.001). At PP, faster skiers and male skiers had a smaller pole angle and greater ankle to hip and ankle to shoulder angle with respect to vertical, resulting in a more distinct forward body lean. However, the majority of the differences are likely due to higher DP velocity.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Esqui/fisiologia , Tornozelo/fisiologia , Fenômenos Biomecânicos , Feminino , Calcanhar/fisiologia , Quadril/fisiologia , Humanos , Masculino , Postura/fisiologia , Fatores Sexuais , Ombro/fisiologia , Equipamentos Esportivos , Estudos de Tempo e Movimento , Gravação em Vídeo
7.
J Strength Cond Res ; 33(3): 606-614, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30789547

RESUMO

Lee, S-P, Gillis, CB, Ibarra, JJ, Oldroyd, DF, and Zane, RS. Heel-raised foot posture does not affect trunk and lower extremity biomechanics during a barbell back squat in recreational weight lifters. J Strength Cond Res 33(3): 606-614, 2019-It is claimed that weightlifting shoes with a raised heel may lead to a more upright trunk posture, and thus reduce the risk of back injuries during a barbell back squat. These proclaimed biomechanical effects have not been thoroughly investigated. The purpose of this study was to compare trunk and lower extremity biomechanics during barbell back squats in three foot postures. Fourteen recreational weight lifters (7 men and 7 women) between the ages of 18 and 50 years performed barbell back squats in three conditions (barefoot on a flat surface, barefoot on a heel-raised platform, and wearing heel-raised weightlifting shoes) at 80% of their 1 repetition maximum. Surface electromyography was used to assess the activation of the knee extensors and paraspinal muscles at L3 and T12 spinal levels. A 3D motion capture system and an electrogoniometer recorded the kinematics of the thoracic spine, lumbar spine, and knee during the back squat to a depth where the hip was at least at the same level to the knee. Results indicated that none of the heel-raised foot postures significantly affected trunk and lower extremity muscle activation (thoracolumbar paraspinal [p = 0.52], lumbar paraspinal [p = 0.179], knee extensor [p = 0.507]) or the trunk angles (thoracolumbar spine [p = 0.348], lumbar spine [p = 0.283]) during the squat. Our results demonstrated that during barbell back squats, heel-raised foot postures do not significantly affect spinal and knee extensor muscle activations, and trunk and knee kinematics. Heel-raised weightlifting shoes are unlikely to provide significant protection against back injuries for recreational weight lifters during the barbell back squat.


Assuntos
Calcanhar/fisiologia , Músculos Paraespinais/fisiologia , Postura/fisiologia , Músculo Quadríceps/fisiologia , Sapatos , Levantamento de Peso/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos , Eletromiografia , Feminino , Humanos , Joelho/fisiologia , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Tronco/fisiologia , Adulto Jovem
8.
J Biomech ; 82: 171-177, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30389258

RESUMO

Previous studies have shown a possible effect of running speed and the sole material of footwear on lower-limb mechanics and soft tissue vibrations, while little information has been offered concerning the influence of the shape of the footwear's sole. The purpose of this study is to assess the effect of running speed and rocker shoes on muscular activity, ground reaction force, and soft tissue vibrations. Twenty participants performed heel-toe running with two shoes, differentiated only by their sole shape (i.e. rocker and non-rocker), at four running speeds. Ground reaction force and electromyograms of the gastrocnemius medialis and vastus lateralis were measured, and soft tissue accelerations of the same muscles were recorded with tri-axial accelerometers. A continuous wavelet transform was applied to the accelerometer's signals to analyse them in the time-frequency domain. The rocker of the shoes did not change the muscular activations, ground reaction force, nor power of soft tissue vibrations. In opposite, increased running speed led to an augmentation of all of the measured parameters. Interestingly, running speed augmentation led to a greater increase in high frequencies component of soft tissue vibrations (25-50 Hz, 242%) than lower ones (8-25 Hz, 111%). Consequently, we indicated a 10% increase in the relative part of the high frequencies of the total power. In conclusion, although rocker shoes have shown an effect on lower-limb kinetics in some studies, no influence on soft tissue vibration is denoted. By contrast, soft tissue vibrations may be modulated by changing running speed.


Assuntos
Extremidade Inferior/fisiologia , Fenômenos Mecânicos , Corrida/fisiologia , Sapatos , Vibração , Fenômenos Biomecânicos , Eletromiografia , Feminino , Calcanhar/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Análise de Ondaletas , Adulto Jovem
9.
J Appl Biomech ; 35(2): 140-148, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30526192

RESUMO

Gait asymmetry is observed after total knee replacement, often leading to excessive forces at the contralateral limb. The number of total knee replacement procedures has increased substantially over the past 2 decades, particularly among younger patients. Relatively little is known regarding these younger patients (<65 y), specifically, with respect to gait asymmetry. The purpose of this study was to investigate if age affects gait asymmetry after unilateral total knee replacement. Three-dimensional analysis of 10 walking trials was collected from the following 4 groups: younger patient (age: 54.3 [7.9] y), younger control (age: 55.2 [4.0] y), older patient (age: 76.9 [4.7] y), and older control (age: 77.7 [4.1] y). The older patients, but not any of the other groups, demonstrated a significantly larger heel strike transient and peak knee adduction moment at the nonsurgical compared with the surgical limb. The observed gait pattern of the younger patients resembled that of the younger controls, rather than the older patients. The greater loading of the nonsurgical limb for the older patients could contribute to the initiation or further progression of osteoarthritic degeneration in the contralateral knee; these asymmetries were not observed for the younger patients.


Assuntos
Fatores Etários , Artroplastia do Joelho , Marcha , Calcanhar/fisiologia , Articulação do Joelho/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Estudos de Casos e Controles , Humanos , Articulação do Joelho/cirurgia , Pessoa de Meia-Idade , Caminhada
10.
Appl Ergon ; 80: 265-271, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28599798

RESUMO

The purpose of this study was to determine the optimal inner-shoe volume for children tennis players. Sixteen participants, aged from 8 to 12 years old assessed comfort of 6 shoes, which were a combination of 3 lasts (thin, medium and wide) and 2 upper constructions (flexible and stiff), while a sock equipped with textile sensors was measuring the pressure applied on their foot. The thin last was based on the proportion of an adult last. The widest shoes produced the lowest pressure on the 1st and 5th metatarsal heads, the medial midfoot and the medial and lateral heel (p < 0.05), whilst they were perceived the most comfortable for the 3rd and 5th metatarsal heads, the 5th metatarsal base and the medial and lateral heel (p < 0.05). These outcomes indicated that footwear manufacturers should design wider shoes for children than for adults.


Assuntos
Desenho de Equipamento/psicologia , Sapatos , Equipamentos Esportivos , Tênis/fisiologia , Fenômenos Biomecânicos , Criança , Comportamento do Consumidor , Feminino , Pé/fisiologia , Calcanhar/fisiologia , Humanos , Masculino , Ossos do Metatarso/fisiologia , Pressão , Tênis/psicologia
11.
Gait Posture ; 68: 305-310, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30553152

RESUMO

BACKGROUND: To better understand gait initiation in individuals with stroke and suggest possible training strategies, we compared the gait initiation of individuals with stroke and age-matched controls, and we examined the influence of different amounts of body weight support (BWS) during the execution of gait initiation in individuals with stroke. MATERIALS AND METHODS: Twelve individuals with stroke and 12 age-matched controls initiated gait after a verbal command at a self-selected and comfortable speed, and individuals with stroke also initiated gait wearing a harness with 0%, 15%, and 30% of BWS. Length and velocity of the first step, distance between heels, and weight bearing in both lower limbs in the initial position were calculated. We also assessed the displacement and average velocity of the center of pressure (CoP) in the medial-lateral (ML) and anterior-posterior (AP) directions in 3 distinct sections during gait initiation, which correspond to the CoP position toward the swing limb, stance limb and progression line, respectively. RESULTS: Individuals with stroke presented shorter and slower step, shorter and slower CoP-ML and CoP-AP toward swing limb and Cop-ML towards stance limb, and longer and faster CoP-AP toward stance limb compared to their peers. The BWS lead individuals with stroke to decrease step length and to increase CoP-ML displacement and average velocity toward stance limb. CONCLUSION: Individuals with stroke present impairments in executing gait initiation mainly during the preparation period and the employment of an overground BWS system promotes a better performance. These results suggest that BWS is a functional strategy that enables individuals with stroke to modulate gait initiation and it could be adopted for gait intervention.


Assuntos
Peso Corporal/fisiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Marcha/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/complicações , Suporte de Carga/fisiologia , Idoso , Análise de Variância , Feminino , Transtornos Neurológicos da Marcha/reabilitação , Calcanhar/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dedos do Pé/fisiologia
12.
Foot (Edinb) ; 37: 65-70, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30326414

RESUMO

Initial heel contact is an important attribute of gait, and failure to complete the heel rocker reduces gait stability. One common goal in treating toe-walking is to restore heel strike and prevent or reduce early heel rise. Foot floor angle (FFA) is a measure of toe-walking that is valuable for quantifying foot orientation at initial contact when using ankle dorsiflexion angle alone is misleading. However, no age-standardized FFA norms exist for clinical evaluation. Our objectives were to: (1) obtain normative FFA in typically developing children; and (2) examine its utility in the example of toe-walking secondary to unilateral cerebral palsy. Gait kinematics were acquired and FFA trajectories computed for 80 typically developing children (4-18 years). They were also obtained retrospectively from 11 children with toe-walking secondary to unilateral cerebral palsy (4-10 years), before and after operative intervention, and compared to 40 age-matched, typically developing children. FFA at initial contact was significantly different (P<.001) between pre-surgery toe-walking (-14.7±9.7°; mean±standard deviation) and typical gait (18.7±2.8°). Following operative lengthening of the gastrocnemius-soleus complex on the affected side, FFA at initial contact (-0.9±5.3°) was significantly improved (P<.001). Furthermore, several cases were identified for which the sole use of ankle dorsiflexion angle to capture toe-walking is misleading. The assessment of FFA is a simple method for providing valuable quantitative information to clinicians regarding foot orientation during gait. The demonstrated limitations of using ankle dorsiflexion angle alone to estimate foot orientation further emphasize the utility of FFA in assessing toe-walking.


Assuntos
Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/reabilitação , Articulações do Pé/fisiologia , Marcha/fisiologia , Calcanhar/fisiologia , Dedos do Pé/fisiologia , Adolescente , Paralisia Cerebral/complicações , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino
13.
IEEE Trans Neural Syst Rehabil Eng ; 26(10): 1945-1956, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30334739

RESUMO

A benchmark and time-effective computational method is needed to assess human gait events in real-life walking situations using few sensors to be easily reproducible. This paper fosters a reliable gait event detection system that can operate at diverse gait speeds and on diverse real-life terrains by detecting several gait events in real time. This detection only relies on the foot angular velocity measured by a wearable gyroscope mounted in the foot to facilitate its integration for daily and repeated use. To operate as a benchmark tool, the proposed detection system endows an adaptive computational method by applying a finite-state machine based on heuristic decision rules dependent on adaptive thresholds. Repeated measurements from 11 healthy subjects (28.27 ± 4.17 years) were acquired in controlled situations through a treadmill at different speeds (from 1.5 to 4.5 km/h) and slopes (from 0% to 10%). This validation also includes heterogeneous gait patterns from nine healthy subjects (27 ± 7.35 years) monitored at three self-selected paces (from 1 ± 0.2 to 2 ± 0.18 m/s) during forward walking on flat, rough, and inclined surfaces and climbing staircases. The proposed method was significantly more accurate ( ) and time effective (< 30.53 ± 9.88 ms, ) in a benchmarking analysis with a state-of-the-art method during 5657 steps. Heel strike was the gait event most accurately detected under controlled (accuracy of 100%) and real-life situations (accuracy > 96.98%). Misdetection was more pronounced in middle mid swing (accuracy > 90.12%). The lower computational load, together with an improved performance, makes this detection system suitable for quantitative benchmarking in the locomotor rehabilitation field.


Assuntos
Marcha/fisiologia , Adulto , Benchmarking , Fenômenos Biomecânicos , Feminino , Análise de Elementos Finitos , Pé/fisiologia , Voluntários Saudáveis , Calcanhar/fisiologia , Humanos , Masculino , Desempenho Psicomotor , Reprodutibilidade dos Testes , Caminhada/fisiologia , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
14.
BMC Complement Altern Med ; 18(1): 264, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30268162

RESUMO

BACKGROUND: One of the most common orthopedic problems is the incidence of pressure ulcer followed by immobility. This study aimed to investigate the effect of Aloe Vera gel on the prevention of pressure ulcer in patients hospitalized in the orthopedic ward. METHOD: This study is a randomized, triple-blind clinical trial which was done on 80 purposefully selected patients in orthopedic ward in Arak town, Iran, 2016. Patients were randomly assigned into two intervention and control groups based on blocking sampling method. In each group the routine daily cares to prevent bed sores were performed by nurses. In the intervention group in addition to routine nursing care to prevent bed sores, twice a day (hours of 9 and 21) pure Aloe Vera gel on the areas of hip, sacrum and heel were rubbed, but in the control group placebo (gel of water and starch) were used. Then sacral, hip and heel of both groups on days 3, 7 and 10 for of signs of pressure ulcers was evaluated. RESULTS: The mean age of patients in the control group was (42.34 ± 12.19) and in the intervention group Was (41.71 ± 11.50) years, respectively. In the intervention group 1 patient afflicted with sore of hip and two people with sacral pressure ulcer. In the control group 3 patients affiliated with sore of hip, 8 people with sacral pressure ulcer, and 1 person had pressure sore of heel. Analysis of the data showed that both groups had statistically significant differences in the incidence of pressure ulcers (P = 0.047). This means that Aloe Vera gel could prevent the occurrence of pressure ulcers in the intervention group. CONCLUSION: Due to the effect of Aloe Vera gel to prevent a rise in temperature, non-blanchable redness, swelling and pain of the skin of regions under study in hospitalized patients in the orthopedic ward, applying of it toward the prevention of pressure ulcers in patients at risk of pressure ulcer development is recommended. TRIAL REGISTRATION: This study was registered in Iranian Registry of Clinical. Trials in 07/09/2016 with the IRCT ID: IRCT2016051027825N1 .


Assuntos
Preparações de Plantas/uso terapêutico , Lesão por Pressão/tratamento farmacológico , Lesão por Pressão/prevenção & controle , Adulto , Temperatura Corporal/fisiologia , Feminino , Calcanhar/fisiologia , Quadril/fisiologia , Hospitalização , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/terapia , Região Sacrococcígea/fisiologia
15.
PLoS One ; 13(10): e0205906, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30335813

RESUMO

The purpose of this study was to clarify whether foot strike patterns are associated with different sprint performance and kinematics in preadolescent boys. The study enrolled 24 healthy 10-11-year-old boys in the fifth grade at public elementary schools in Japan. The participants performed the 50-m sprint with maximum effort. Sprint motion was recorded using a high-speed video camera (120 fps) placed in the sagittal plane on the left side of a line drawn at 35-m from the start line. Kinematic variables were calculated based on manually digitized body landmark coordinates. The participants were categorized into two groups according to their foot strike pattern (rearfoot strikers, RF group, n = 12; forefoot or midfoot strikers, FF/MF group, n = 12). The time taken to complete the 50-m sprint in the FF/MF group (9.08±0.52 s) was faster than that in the RF group (9.63±0.51 s). The FF/MF group had greater sprint speed, higher step frequency, and shorter foot contact time than the RF group. Regarding the association between foot strike pattern and sprint kinematics, we found that the RF group had a greater range of knee flexion during the support-leg phase, whereas the FF/MF group had shorter horizontal distance from the heel of the support leg to the centre of mass at the touchdown, greater maximal knee flexion velocity during the swing-leg phase, and higher the maximum hip extension velocity during the support-leg phase. The current results suggested that, in preadolescent boys, forefoot or midfoot strike (rather than rearfoot strike) is effective for obtaining a higher step frequency and sprint speed through greater magnitude of knee flexion and hip extension movement velocities during the swing and support phases, respectively. The current findings will be useful for understanding the characteristics of the development of sprinting performance in preadolescent children.


Assuntos
Antepé Humano/fisiologia , Calcanhar/fisiologia , Articulação do Joelho/fisiologia , Amplitude de Movimento Articular/fisiologia , Corrida/fisiologia , Fenômenos Biomecânicos , Criança , Antepé Humano/anatomia & histologia , Marcha/fisiologia , Calcanhar/anatomia & histologia , Humanos , Articulação do Joelho/anatomia & histologia , Masculino , Gravação em Vídeo
16.
J Biomech ; 80: 144-150, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30241799

RESUMO

This study combines non-invasive mechanical testing with finite element (FE) modelling to assess for the first time the reliability of shear wave (SW) elastography for the quantitative assessment of the in-vivo nonlinear mechanical behavior of heel-pad. The heel-pads of five volunteers were compressed using a custom-made ultrasound indentation device. Tissue deformation was assessed from B-mode ultrasound and force was measured using a load cell to calculate the force - deformation graph of the indentation test. These results were used to design subject specific FE models and to inverse engineer the tissue's hyperelastic material coefficients and its stress - strain behavior. SW speed was measured for different levels of compression (from 0% to 50% compression). SW speed for 0% compression was used to assess the initial stiffness of heel-pad (i.e. initial shear modulus, initial Young's modulus). Changes in SW speed with increasing compressive loading were used to quantify the tissue's nonlinear mechanical behavior based on the theory of acoustoelasticity. Statistical analysis of results showed significant correlation between SW-based and FE-based estimations of initial stiffness, but SW underestimated initial shear modulus by 64%(±16). A linear relationship was found between the SW-based and FE-based estimations of nonlinear behavior. The results of this study indicate that SW elastography is capable of reliably assessing differences in stiffness, but the absolute values of stiffness should be used with caution. Measuring changes in SW speed for different magnitudes of compression enables the quantification of the tissue's nonlinear behavior which can significantly enhance the diagnostic value of SW elastography.


Assuntos
Calcanhar/diagnóstico por imagem , Calcanhar/fisiologia , Adulto , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Análise de Elementos Finitos , Humanos , Pressão , Reprodutibilidade dos Testes , Estresse Mecânico , Ultrassonografia
17.
J Electromyogr Kinesiol ; 43: 41-47, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30223254

RESUMO

Individuals with plantar flexor weakness often require rehabilitation and/or orthoses, which should be personalized based on level of weakness. While plantar flexor weakness can be measured via peak plantar flexion moment during gait (MGAIT), motion analysis systems are often not clinically available. Clinical measures, such as the single-leg heel rise (SLHR) test and isometric muscle test, may provide surrogate measures of plantar flexor function during gait. However, it is currently unknown if a relationship(s) exists between such measures. This study evaluated the relationship between gait and clinical measures of plantar flexor function for typical individuals. Twenty-four participants underwent an instrumented gait analysis, from which MGAIT was calculated. Next, participants performed an isometric plantar flexor test, from which the maximum plantar flexion moment (MISO) was calculated. Finally, participants performed a SLHR test, from which maximum plantar flexion moment (MSLHR) and total work (Wtot_SLHR) were calculated. Via Pearson correlations, MSLHR was most strongly correlated to MGAIT (r = 0.56; p = 0.005). Wtot_SLHR was significantly correlated to MGAIT (r = 0.47; p = 0.019). MISO was not significantly correlated to MGAIT (r = 0.19; p = 0.363). MSLHR and/or Wtot_SLHR may provide clinically-feasible surrogate measures of plantar flexor function during gait.


Assuntos
Marcha/fisiologia , Calcanhar/fisiologia , Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Adulto , Idoso , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Neurosci Lett ; 686: 41-46, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30176343

RESUMO

Skin, as the largest organ of the human body, has various important functions, like protecting from dehydration or preventing the intrusion of microorganisms. Certain external factors have been shown to negatively influence skin functions. One of those factors is long-term (several hours) exposure to liquids, such as water, leading to skin softening. This study aimed to examine whether detrimental effects, such as skin softening, already exist after short-term water exposure. Furthermore, we investigated whether cutaneous sensation is altered by short-term water exposure. Thirty healthy subjects participated in this study (23.1 ± 2.5yrs, 173.7 ± 8.5 cm, 67.5 ± 9.8 kg). First, vibration perception thresholds (VPTs; 200 Hz), the skin´s elasticity (logarithmic decrement), and the skin´s mechanical deformation resistance properties (durometer readings) were measured at the plantar aspect of the hallux and heel of both feet (pre). Subsequently, one randomly chosen foot was immersed in water (45 min; water temperature adjusted to the foot pre temperatures). The contra-lateral foot remained untreated and out of the water. After the intervention, all three above-mentioned parameters were measured again in the same manner (post). Inferential statistical tests to detect differences regarding elasticity, durometer readings, and VPTs were performed based on logarithmically transformed data (natural logarithm). VPTs did not show significant differences. However, an overall increased elasticity and a softening effect of the skin were evident due to the water exposure at both anatomical locations. This study showed that 45 min of water exposure induces changes in plantar skin properties similar to the long-term effects described in other studies. Most importantly, the short-term water exposure resulted in a softening effect, which may affect skin perfusion in a negative manner. This may facilitate skin irritations and even future ulcer formation. We also showed that changes in mechanical skin properties induced by water exposure did not influence plantar cutaneous sensation. The findings of this study are especially relevant for people with impaired skin recovery mechanisms and highlight the importance of keeping skin dry, particularly in people who are bedridden.


Assuntos
Pé/fisiologia , Limiar Sensorial/fisiologia , Fenômenos Fisiológicos da Pele , Água , Adulto , Feminino , Calcanhar/fisiologia , Humanos , Masculino , Pele/inervação , Estresse Mecânico
19.
J Foot Ankle Res ; 11: 49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30186369

RESUMO

Background: Posterior tibial tendon dysfunction (PTTD) is a painful, progressive tendinopathy that reportedly predominates in middle-age, overweight women. There is no evidence based guidelines that clinicians can use to guide treatment planning, which leaves clinicians to make decisions on the basis of presenting clinical impairments and self-reported pain and disability. The purpose of this systematic review was to quantify clinical impairments, pain and disability in individuals with PTTD compared with controls. Methods: Five databases were searched for terms referring to the posterior tibial tendon and flatfoot up to and including 11 March 2018. The systematic review was registered with PROSPERO (CRD: 42016046951). Studies were eligible if they were published in the English language and contained data on clinical impairments, pain or disability compared between participants diagnosed with PTTD and pain-free individuals. Standardised mean differences (SMDs) were calculated where possible and meta-analysis was performed when homogeneity of outcomes allowed. Results: Ten eligible studies were identified and pooled in the meta-analyses. Strong effects were revealed for poor heel rise endurance (SMD -1.52, 95% CI -2.05 to - 0.99), less forefoot adduction-inversion strength (SMD -1.19, 95% CI -1.68 to - 0.71) and lower arch height (SMD -1.76, 95% CI -2.29 to - 1.23). Compared to controls, individuals with PTTD also had more self-reported stiffness (SMD 1.45, 95% CI 0.91 to 1.99), difficulties caused by foot problems (SMD 1.42, 95% CI 0.52 to 2.33) and social restrictions (SMD1.26, 95% CI 0.25 to 2.27). Conclusion: There is evidence of impaired tibialis posterior capacity and lowered arch height in individuals with PTTD compared to controls. Further to addressing the expected impairments in local tendon function and foot posture, pain, stiffness, functional limitations and social participation restrictions should be considered when managing PTTD.


Assuntos
Disfunção do Tendão Tibial Posterior/fisiopatologia , Participação Social , Atividades Cotidianas , Adulto , Pessoas com Deficiência , Feminino , Calcanhar/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Disfunção do Tendão Tibial Posterior/psicologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Amplitude de Movimento Articular/fisiologia , Autorrelato , Caminhada/fisiologia
20.
J Biomech ; 77: 171-182, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30033382

RESUMO

Rupture of anterior cruciate ligament (ACL) undermines normal activity and function of the knee joint and places it at higher risk of re-injury and degeneration. ACL reconstruction surgery neither necessarily ensures return to pre-injury activities nor alleviates risk of long-term degeneration. Here in this computational investigation of a lower-extremity hybrid model at heel strike (HS) of gait, we search for factors that influence the stability of the joint and hence the distinct performances between post-ACL injury copers and non-copers. Due to the very unstable state of the joint under the mean gait input data, joint rotations-moments, posterior tibial slope (PTS), and cocontraction were altered within the reported data in the literature and the effects on the joint stability (anterior tibial translation (ATT) and critical muscle stiffness coefficient (qcr)) were investigated. Results indicate that, in presence of both a small extension moment (0.1 or 0.2 Nm/kg) and a flexion rotation (∼5-8°), ACL-deficient (ACL-D) knee joint stability substantially improves to levels computed in the pre-injury intact joint. In addition, low cocontraction levels of 1-3% (in hamstrings and quads only and not in gastrocnemii) and reduced PTS (by 5°) further improve ACL-D joint stability. Therefore for a stable joint with ATT < 3 mm and qcr < 25 similar to those in the intact knee at HS, higher flexion angles (>5°) and a small extension moment (∼0.1-0.2 Nm/kg) (i.e., higher activity in hamstrings than quads) are required. A lower posterior tibial slope (by 5°) and a small minimum cocontraction level (1-3%) in hamstrings and quads (but not in gastrocnemii) are also beneficial. These results identify mechanisms likely in play at HS in gait of copers when compared to non-copers.


Assuntos
Ligamento Cruzado Anterior/fisiologia , Calcanhar/fisiologia , Articulação do Joelho/fisiologia , Fenômenos Mecânicos , Contração Muscular , Tíbia/fisiologia , Fenômenos Biomecânicos , Feminino , Marcha/fisiologia , Humanos , Cinética , Rotação
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