RESUMO
OBJECTIVE: Investigate the effects of multisensory training with and without the anchor system on breast cancer survivors' postural balance and self-efficacy of falls. DESIGN: Clinical randomized, controlled, and crossover trial. SETTING: Teaching, Research, and Assistance Center in Mastectomized Rehabilitation. PARTICIPANTS: Eighty breast cancer survivors homogeneously distributed in the groups of adults and elderly affected, or not, by lymphedema. INTERVENTIONS: Participants were randomized to multisensory training with and without the anchor system involving 3 sessions per week for 12 weeks. After the 4-week washout period, the remaining therapeutic intervention was applied. MAIN OUTCOME MEASURES: The primary outcome was semi-static and dynamic balance as evaluated by baropodometry and Mini Balance Evaluation Systems Test, and the secondary outcome was self-efficacy of the fall episode as assessed by Falls Efficacy Scale - International in the pre-, post-immediate, and 4-week follow-up period. RESULTS: Both therapeutic interventions caused positive and significant effects on postural balance and self-efficacy of falls in the immediate period. The multisensory training with the anchor system induced significant functional retention in the short term, related to the clinical effect of small to moderate variation. CONCLUSIONS: Multisensory training with the anchor system is convenient for postural balance and self-efficacy for falls, regardless of age and upper limb volume, for breast cancer survivors.
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Neoplasias da Mama , Terapia por Exercício , Idoso , Feminino , Humanos , Estudos Cross-Over , Modalidades de Fisioterapia , Equilíbrio Postural , AdultoRESUMO
Loading both lateral and medial compartments is crucial to understanding the effect of muscle fatigue during sidestep cutting. The present study investigated the changes in tibiofemoral contact forces in the medial and lateral compartments and the muscle force contributions during the sidestep-cutting manoeuvre after a handball-specific fatigue protocol. Twenty female handball athletes performed three trials of the sidestep-cutting manoeuvre before (baseline) and after the fatigue protocol. Motion capture and ground reaction forces were measured, and the data were processed in OpenSim. The variables were compared using statistical parametric mapping (SPM), with a significance level of p < 0.05. The results showed a decreased knee flexion angle during fatigue in the early stance phase. In addition, the post-fatigue analysis demonstrated significantly reduced forces in vasti muscles. Similarly, during fatigue, the SPM analysis showed decreased tibiofemoral contact forces in the vertical and anterior directions. Vertical force applied to both medial and lateral condyles demonstrated a significant reduction after the fatigue protocol. These results indicated that forces applied to the tibiofemoral joint were reduced following the fatigue protocol compared to the baseline values. However, no consistent evidence exists that fatigue increases the risk of knee injuries.
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Articulação do Joelho , Fadiga Muscular , Humanos , Feminino , Fenômenos Biomecânicos , Fadiga Muscular/fisiologia , Adulto Jovem , Articulação do Joelho/fisiologia , Esportes/fisiologia , Músculo Esquelético/fisiologia , Estudos de Tempo e Movimento , Joelho/fisiologia , Movimento/fisiologiaRESUMO
Older adults adapt the execution of complex motor tasks to use compensatory strategies in the reaching-to-grasping (i.e., prehension) movement. The presence of postural constraints may exacerbate these compensatory strategies. Therefore, we investigated the reach-to-grasp action with different postural constraints (sitting, standing, and walking) in younger and older people and evaluated the postural stability during the reach-to-grasp action. Thirty individuals (15 younger and 15 older adults) performed the prehension under three postural tasks: sitting, standing, and walking. The reaching movement was slower in the walking task than in the other two postural tasks; however, there was no difference between the age groups. For the grasping action, the older adults presented a larger grip aperture, and the peak grip aperture occurred earlier during hand transportation in sitting and standing tasks. In the standing task, the margin of stability was smaller for older adults. In the walking task, there was no difference between the groups for the margin of stability. Also, prehension during sitting and standing tasks were similar, and both differed from walking across age groups. Finally, older adults reduced their margin of stability compared to younger adults, but only in the standing task. The margin of stability was similar between age groups during the walking task. We concluded that age affected grasping (distal component) but not reaching (proximal component), suggesting that healthy older adults have more difficulty controlling distal than proximal body segments.
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Mãos , Caminhada , Humanos , Idoso , Movimento , Posição Ortostática , Postura Sentada , Equilíbrio PosturalRESUMO
Bone lesions have the capacity for regeneration under normal conditions of the bone metabolism process. However, due to the increasing incidence of major traumas and diseases that cause bone-mineral deficiency, such as osteoporosis, scaffolds are needed that can assist in the bone regeneration process. Currently, natural polymeric scaffolds and bioactive nanoparticles stand out. Therefore, the objective of the study was to evaluate the osteoregenerative potential in tibiae of healthy and ovariectomized rats using mineralized collagen and nanohydroxyapatite (nHA) scaffolds associated with elastin. The in-vivo experimental study was performed with 60 20-week-old Wistar rats, distributed into non-ovariectomized (NO) and ovariectomized (O) groups, as follows: Controls (G1-NO-C and G4-O-C); Collagen with nHA scaffold (G2-NO-MSH and G5-O-MSH); and Collagen with nHA and elastin scaffold (G3-NO-MSHC and G6-O-MSHC). The animals were euthanized 6 weeks after surgery and the samples were analyzed by macroscopy, radiology, and histomorphometry. ANOVA and Tukey tests were performed with a 95% CI and a significance index of p < 0.05. In the histological analyses, it was possible to observe new bone formed with an organized and compact morphology that was rich in osteocytes and with maturity characteristics. This is compatible with osteoconductivity in both matrices (MSH and MSHC) in rats with normal conditions of bone metabolism and with gonadal deficiency. Furthermore, they demonstrated superior osteogenic potential when compared to control groups. There was no significant difference in the rate of new bone formation between the scaffolds. Ovariectomy did not exacerbate the immune response but negatively influenced the bone-defect repair process.
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Durapatita , Elastina , Feminino , Ratos , Animais , Humanos , Ratos Wistar , Colágeno , Osteogênese , Regeneração Óssea , Ovariectomia , Alicerces Teciduais , Engenharia TecidualRESUMO
OBJECTIVE: To assess the balance sensory organization among patients with migraine, considering the influence of migraine subdiagnosis, otoneurological function, falls, and psychosocial factors. BACKGROUND: Migraine has been associated with vestibular symptoms and balance dysfunction; however, neither comprehensive balance assessment nor associated factors for greater impairment have been addressed thus far. METHODS: Patients from a tertiary headache clinic with a diagnosis of episodic migraine with aura (MWA), without aura (MWoA), and chronic migraine (CM) were included for this cross-sectional study (30 patients per group). Thirty headache-free controls (CG) were recruited. Participants underwent a comprehensive evaluation protocol, including the Sensory Organization Test (SOT) and otoneurological examination. Questionnaires about fear of falls, dizziness disability, and kinesiophobia were administered. RESULTS: All migraine groups presented lower composite SOT scores than controls (CG: 82.4 [95% confidence interval (CI): 79.5-85.3], MWoA: 76.5 [95% CI: 73.6-79.3], MWA: 66.5 [95% CI: 63.6-69.3], CM: 69.1 [95% CI: 66.3-72.0]; p < 0.0001). Compared to controls and to MWoA, MWA and CM groups exhibited greater vestibular (CG: 75.9 [95% CI: 71.3-80.4], MWoA: 67.3 [95% CI: 62.7-71.8], MWA: 55.7 [95% CI: 51.2-60.3], CM: 58.4 [95% CI: 53.8-63.0]; p < 0.0001) and visual functional impairment (CG: 89.6 [95% CI: 84.2-94.9], MWoA: 83.2 [95% CI: 77.9-88.6], MWA: 68.6 [95% CI: 63.3-74.0], CM: 71.9 [95% CI: 66.5-77.2], p < 0.0001). Fall events during the assessment were documented more often among patients with migraine (CG: 0.0, interquartile range [IQR], 0.0, 0.0); MWoA: 1.0 [IQR: 1.0, 1.0], MWA: 2.0 [IQR: 1.8, 4.3], CM: 1.0 [IQR: 1.0, 2.0]; p = 0.001). The SOT scores correlated with fear of falls (r = -0.44), dizziness disability (r = -0.37), kinesiophobia (r = -0.38), and migraine frequency (r = -0.38). There was no significant influence of the vestibular migraine diagnosis in the study outcomes when used as a covariate in the analysis (composite score [F = 3.33, p = 0.070], visual score [F = 2.11, p = 0.149], vestibular score [F = 1.88, p = 0.172], somatosensory score [F = 0.00, p = 0.993]). CONCLUSIONS: Aura and greater migraine frequency were related to falls and balance impairment with sensory input manipulation, although no otoneurological alterations were detected. The diagnosis of vestibular migraine does not influence the balance performance. The vestibular/visual systems should be considered in the clinical examination and treatment of patients with migraine.
Assuntos
Epilepsia , Transtornos de Enxaqueca , Enxaqueca com Aura , Estudos Transversais , Tontura/diagnóstico , Tontura/etiologia , Epilepsia/complicações , Humanos , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/diagnóstico , Equilíbrio Postural , Vertigem/complicações , Vertigem/diagnósticoRESUMO
This study investigated the effect of a handball-specific fatigue protocol on hip and knee kinematics. Twenty female handball athletes performed three trials of the single-leg landing (SLL), sidestep cutting manoeuvre (SCM), and drop vertical jump (DVJ) before and after the fatigue protocol. Knee and hip angle waveforms were compared using statistical parametric mapping (p < 0.05). During the SLL, the fatigue increased hip adduction (4-7% cycle) and knee abduction (4-9% and 25-27%). For the SCM, hip flexion was reduced under fatigue during 14-29% and 44-68% of the cycle. Similarly, the knee flexion decreased between 7-36% and 53-73%. Besides, during the fatigue state, the athletes reduced the hip abduction between 0-11% of the cycle and increased the knee abduction between 20-23%. During the DVJ task, when fatigued, the hip flexion decreased between 19-44% of the cycle and the knee flexion between 1-16% and 18-77%. The fatigue protocol altered the lower limb kinematics, decreasing knee and hip flexions during the SCM and DVJ and increasing the knee valgus during both single-leg landing tasks.
Assuntos
Lesões do Ligamento Cruzado Anterior , Esportes , Feminino , Humanos , Fenômenos Biomecânicos , Perna (Membro) , Articulação do Joelho , Fadiga , Articulação do QuadrilRESUMO
OBJECTIVE: This study investigated the effects of star-shape Kinesio taping (KT) compared with both sham KT and minimal intervention (MI) on pain intensity and postural control. DESIGN: Randomized controlled trial. SETTING: Outpatient physical therapy. PARTICIPANTS: A total of 120 people with chronic low back pain (CLBP) aged 18-60 years (N=120). INTERVENTIONS: Star-shape KT, sham KT (no tension), and MI (educational booklet for self-management counseling). MAIN OUTCOME MEASURES: The primary outcome measures were pain intensity and center of pressure (COP) mean sway speed, and disability score (Oswestry Disability Index) was a secondary outcome. The outcomes were obtained immediately after initial KT application, on the seventh day of intervention and at the 1-month follow-up. Linear mixed-model analyses using Bonferroni post hoc analyses were applied to investigate between-group differences. The model included treatment, time, and treatment×time interaction as fixed effects. RESULTS: Pain intensity was significantly lower for the star-shape KT group than for the MI group (mean difference [MD], -1.35; 95% confidence interval [CI], -2.63 to -0.07) immediately after the intervention and on the seventh day of intervention (MD, -1.32; 95% CI, -2.56 to -0.07). No difference in pain intensity between star-shape KT vs sham-KT groups was observed. In addition, no significant between-group differences were observed for the COP mean sway speed and disability score at any of the follow-up times. CONCLUSIONS: Our results showed no meaningful effect of star-shape KT intervention on pain intensity and postural control in people with CLBP compared with MI or sham KT. The observed reduction of 1.3 units between star-shape KT and MI groups was statistically different, but it could not be considered clinically relevant. The results of this trial suggest that benefits from KT are more likely attributable to contextual factors rather than specific taping parameters.
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Fita Atlética , Dor Lombar/fisiopatologia , Dor Lombar/terapia , Manejo da Dor/métodos , Equilíbrio Postural/fisiologia , Adulto , Dor Crônica/fisiopatologia , Dor Crônica/terapia , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Inquéritos e QuestionáriosRESUMO
Autologous bone grafts, used mainly in extensive bone loss, are considered the gold standard treatment in regenerative medicine, but still have limitations mainly in relation to the amount of bone available, donor area, morbidity and creation of additional surgical area. This fact encourages tissue engineering in relation to the need to develop new biomaterials, from sources other than the individual himself. Therefore, the present study aimed to investigate the effects of an elastin and collagen matrix on the bone repair process in critical size defects in rat calvaria. The animals (Wistar rats, n = 30) were submitted to a surgical procedure to create the bone defect and were divided into three groups: Control Group (CG, n = 10), defects filled with blood clot; E24/37 Group (E24/37, n = 10), defects filled with bovine elastin matrix hydrolyzed for 24 h at 37 °C and C24/25 Group (C24/25, n = 10), defects filled with porcine collagen matrix hydrolyzed for 24 h at 25 °C. Macroscopic and radiographic analyses demonstrated the absence of inflammatory signs and infection. Microtomographical 2D and 3D images showed centripetal bone growth and restricted margins of the bone defect. Histologically, the images confirmed the pattern of bone deposition at the margins of the remaining bone and without complete closure by bone tissue. In the morphometric analysis, the groups E24/37 and C24/25 (13.68 ± 1.44; 53.20 ± 4.47, respectively) showed statistically significant differences in relation to the CG (5.86 ± 2.87). It was concluded that the matrices used as scaffolds are biocompatible and increase the formation of new bone in a critical size defect, with greater formation in the polymer derived from the intestinal serous layer of porcine origin (C24/25).
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Biopolímeros/química , Regeneração Óssea/fisiologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Birrefringência , Matriz Óssea/química , Matriz Óssea/fisiologia , Remodelação Óssea/fisiologia , Substitutos Ósseos/química , Calcificação Fisiológica/fisiologia , Bovinos , Colágeno/química , Colágeno/metabolismo , Elastina/química , Elastina/metabolismo , Imageamento Tridimensional , Masculino , Teste de Materiais , Ratos , Ratos Wistar , Crânio/diagnóstico por imagem , Crânio/lesões , Crânio/fisiologia , Suínos , Engenharia Tecidual/métodos , Microtomografia por Raio-XRESUMO
Noncontact anterior cruciate ligament ruptures generally occur during unanticipated sidestep cutting maneuvers when athletes have their visual attention focused on the opponent. The authors investigated the influence of uncertainty related to the side to perform the sidestep cutting maneuver on knee kinematics of female handball athletes. A total of 31 female handball athletes performed the sidestep cutting maneuver during anticipated and uncertain conditions. During the uncertain condition, visual cues indicated the direction of the reactive sidestep cutting maneuver. Between-condition differences were compared using the Student t test for paired samples calculated with statistical parametric mapping. Lower knee flexion angle was detected during the uncertain condition compared with the anticipated condition for the nondominant limb (0%-8% of the sidestep cycle). Knee abduction was larger during the uncertain condition for both the dominant (15%-41% of the sidestep cycle) and nondominant (0%-18% of the sidestep cycle) limbs compared with the anticipated condition. The nondominant leg showed higher knee abduction (36%-68% of the sidestep cycle) during the uncertain condition compared with the anticipated condition. The athletes' approach velocity was slower during the uncertain condition. The uncertain condition impacted knee kinematics and potentially positioned the joint at greater risk of injury by decreasing the flexion angle in the nondominant leg and increasing the joint valgus bilaterally.
Assuntos
Lesões do Ligamento Cruzado Anterior , Articulação do Joelho , Atletas , Fenômenos Biomecânicos , Feminino , Humanos , IncertezaRESUMO
BACKGROUND: People with migraine exhibit postural control impairments. These patients also have an increased light sensitivity due to the disease, and it remains during the headache-free period. It is currently unknown if increased lighting levels can alter the balance control, especially in individuals with visual hypersensitivity, such as migraineurs. This study aimed to assess the balance and photophobia of women with migraine and non-headache controls under different light conditions. METHODS: This cross-sectional study consisted of 14 women with migraine (mean ± SD 30.6 ± 8.1 years old) and 14 women without any kind of headache (mean ± SD 27.2 ± 2.8 years old) screened from a tertiary headache clinical hospital and the local community. Quiet standing balance was evaluated during bipodal and unipodal support, under 3 light conditions: ambient (AMB) - 270 lx, visual discomfort threshold (VDT) - 400 lx, and intense visual discomfort (IVD) - 2000 lx. Sway area of the center of pressure was processed and compared between groups. The association of migraine with the risk of presenting a greater imbalance in the discomfort lighting conditions was verified. RESULTS: Compared to the non-headache controls, the migraine group presented greater sway area in bipodal stance under the 3 light conditions (mean difference (95% CI)): AMB 0.81 cm2 (0.19 to 1.43), P = .011; VDT 3.17 cm2 (0.74 to 5.60), P = .001; IVD 5.56 cm2 (2.75 to 8.37), P < .0001. Within-subject analysis showed increased sway area in bipodal stance among all lighting conditions for the migraine group only (mean difference (95% CI)): VDT-AMB 2.20 cm2 (0.23 to 4.18), P = .024; IVD-AMB 4.50 cm2 (2.38 to 6.62), P < .0001, IVD-VDT 2.29 cm2 (0.57 to 4.01), P = .005. The Prevalence Ratio (PR) analysis showed that migraine was associated with the risk of presenting greater imbalance in both bipodal and unipodal standing conditions for both VDT (PR value (95% CI) - bipodal: PR = 4.00 (1.02 to 15.59), P = .045; unipodal: PR = 4.00 (1.43 to 11.15), P = .008), and the IVD (bipodal: PR = 3.33 (1.13 to 9.58), P = .025; unipodal: PR = 5.50 (1.48 to 20.42), P = .010) lighting conditions. CONCLUSION: Photophobia might be a disturbing factor that worsens the balance of patients with migraine during the quiet standing posture.
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Transtornos de Enxaqueca/fisiopatologia , Fotofobia/fisiopatologia , Equilíbrio Postural/fisiologia , Adulto , Estudos Transversais , Feminino , Humanos , Transtornos de Enxaqueca/complicações , Fotofobia/etiologia , Adulto JovemRESUMO
OBJECTIVE: To assess the effectiveness of the anchors in the balance rehabilitation of participants with chronic peripheral vestibulopathy who failed to respond positively to conventional rehabilitation for dynamic balance and gait. DESIGN: Assessor-blind, randomized controlled trial. SETTING: Department of Otoneurology and Laboratory of Assessment and Rehabilitation of Equilibrium. PARTICIPANTS: Women with chronic dizziness of peripheral vestibular origin (N=42), who continued to show otoneurologic symptoms for more than 6 months after starting classic vestibular rehabilitation, with no clinical improvement observed. INTERVENTIONS: Participants were randomly assigned to receive a clinical intervention with the anchor system, a clinical intervention without the anchor system, or no intervention or anchor system. The intervention was based on multi-sensory exercises for 6 weeks, twice a week, totaling 12 sessions, in groups of up to 4 participants, with an average time of 40 minutes per session. MAIN OUTCOME MEASURES: The primary outcome was functional balance as assessed by the short version of the Balance Evaluation Systems Test. The secondary outcomes were gait parameters of step width in meters, step length in meters, and gait speed in meters per second. The measures were assessed preintervention and postintervention, and after a 3-month follow-up period. RESULTS: The proposed intervention was beneficial for dizziness, balance, and gait for both groups studied. At the 3-month follow-up, only the group that used anchors retained the benefits related to the physical aspects of dizziness, balance, and gait. CONCLUSIONS: The present study found that the proposed intervention protocol, with or without the use of anchors, was beneficial for improving the dizziness, balance, and gait. However, retention of the benefits achieved through the exercise protocol was observed only for those using the anchor system, which promotes the use of haptic information. The use of anchors was effective, in short protocols (12wk), with maintenance of results after 3 months.
Assuntos
Terapia por Exercício/métodos , Marcha/fisiologia , Equilíbrio Postural/fisiologia , Doenças Vestibulares/reabilitação , Idoso , Doença Crônica , Avaliação da Deficiência , Terapia por Exercício/instrumentação , Feminino , Humanos , Pessoa de Meia-Idade , Método Simples-CegoRESUMO
BACKGROUND: Dynamic balance keeps the vertical projection of the center of mass within the base of support while walking. Dynamic balance tests are used to predict the risks of falls and eventual falls. The psychometric properties of most dynamic balance tests are unsatisfactory and do not comprise an actual loss of balance while walking. OBJECTIVES: Using beam walking distance as a measure of dynamic balance, the BEAM consortium will determine the psychometric properties, lifespan and patient reference values, the relationship with selected "dynamic balance tests," and the accuracy of beam walking distance to predict falls. METHODS: This cross-sectional observational study will examine healthy adults in 7 decades (n = 432) at 4 centers. Center 5 will examine patients (n = 100) diagnosed with Parkinson's disease, multiple sclerosis, stroke, and balance disorders. In test 1, all participants will be measured for demographics, medical history, muscle strength, gait, static balance, dynamic balance using beam walking under single (beam walking only) and dual task conditions (beam walking while concurrently performing an arithmetic task), and several cognitive functions. Patients and healthy participants age 50 years or older will be additionally measured for fear of falling, history of falls, miniBESTest, functional reach on a force platform, timed up and go, and reactive balance. All participants age 50 years or older will be recalled to report fear of falling and fall history 6 and 12 months after test 1. In test 2, seven to ten days after test 1, healthy young adults and age 50 years or older (n = 40) will be retested for reliability of beam walking performance. CONCLUSION: We expect to find that beam walking performance vis-à-vis the traditionally used balance outcomes predicts more accurately fall risks and falls. CLINICAL TRIAL REGISTRATION NUMBER: NCT03532984.
Assuntos
Acidentes por Quedas/estatística & dados numéricos , Esclerose Múltipla/fisiopatologia , Doença de Parkinson/fisiopatologia , Equilíbrio Postural/fisiologia , Transtornos de Sensação/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Caminhada , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Adulto JovemRESUMO
During locomotion, we respond to environmental and task changes by adjusting steps length and width. Different protocols involving stepping on targets and obstacle avoidance suggest the involvement of cortical and subcortical pathways in these online adjustments. The addition of a concomitant cognitive task (CT) can affect these online corrections depending on the neural pathway used. Thereby, we investigated the online adjustment using a target stepping task and a planar obstacle avoidance task in young adults and analyzed the effect of a CT on these adjustments. Twenty young adults executed two blocks of trials of walking performing the target task (TT) and obstacle avoidance task (OAT), with and without a concomitant CT. In the TT, participants stepped on a target projected on the ground, whereas in the OAT they avoided stepping on an obstacle projected on the ground. The target/obstacle could change its original position in four directions at contralateral foot contact on the ground. Overall, the CT did not affect the latency to start the adjustments due to target/obstacle change. The main changes were restricted to the frontal plane adjustments. The latency for the medial and lateral choices in the OAT was ~ 200 ms, whereas for the TT was ~ 150 ms. These results suggest the involvement of a slow cortical pathway in the OAT in the frontal plane modifications. In turn, the TT may be controlled by one of two fast adjustment neural pathways.
Assuntos
Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
There are different ways to add haptic input during walking which may affect walking balance. This study compared the use of two different haptic tools (rigid railing and haptic anchors) and investigated whether any effects on walking were the result of the added sensory input and/or the posture generated when using those tools. Data from 28 young healthy adults were collected using the Mobility Lab inertial sensor system (APDM, Oregon, USA). Participants walked with and without both haptic tools and while pretending to use both haptic tools (placebo trials), with eyes opened and eyes closed. Using the tools or pretending to use both tools decreased normalized stride velocity (p < .001-0.008) and peak medial-lateral (ML) trunk velocity (p < .001-0.001). Normalized stride velocity was slower when actually using the railing compared to placebo railing trials (p = .006). Using the anchors resulted in lower peak ML trunk velocity than the railing (p = .002). The anchors had lower peak ML trunk velocity than placebo anchors (p < .001), but there was no difference between railing and placebo railing (p > .999). These findings highlight a difference in the type of tool used to add haptic input and suggest that changes in balance control strategy resulting from using the railing are based on arm placement, where it is the posture combined with added sensory input that affects balance control strategies with the haptic anchors. These findings provide a strong framework for additional research to be conducted on the effects of haptic input on walking in populations known to have decreased walking balance.
Assuntos
Equilíbrio Postural/fisiologia , Percepção do Tato/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The production, distribution and use of electricity can generate low frequency electric and magnetic fields (50-60 Hz). Considering that some studies showed adverse effects on pancreatic ß-cells exposed to these fields; the present study aimed to analyze the effects of 60 Hz electric fields on membrane potential during the silent and burst phases in pancreatic ß-cells using a mathematical model. Sinusoidal 60 Hz electric fields with amplitude ranging from 0.5 to 4 mV were applied on pancreatic ß-cells model. The sinusoidal electric field changed burst duration, inter-burst intervals (silent phase) and spike sizes. The parameters above presented dose-dependent response with the voltage amplitude applied. In conclusion, theoretical analyses showed that a 60 Hz electric field with low amplitudes changes the membrane potential in pancreatic ß-cells.
Assuntos
Eletricidade , Ilhotas Pancreáticas/fisiologia , Potenciais da Membrana , Potenciais de Ação , Simulação por ComputadorRESUMO
We investigated postural stability through the margin of stability (MoS) while reaching and grasping an object with increasing difficulty levels in younger, fallers and non-fallers. Forty-five individuals distributed into three groups participated in this study: younger adults (YA), non-fallers (OA), and fallers (FOA). They stood upright and reached and grasped a dowel. Six conditions combining the stability of the dowel's base and obstacles close to the dowel were manipulated to characterize different difficulty levels. We computed the MoS in both anterior-posterior (AP) and medial-lateral (ML) directions in the interval between reaching onset and dowel contact. From the MoS time series, we analyzed the minimum and maximum, including the time of occurrence of these events. The MoS was smaller for OA than for YA in both directions. In the ML direction, the minimum MoS was smaller for FOA than for YA. The minimum MoS took place earlier for FOA than YA in the AP direction. FOA and OA exhibited similar behavior with reduced MoS, suggesting impaired postural control during reaching-to-grasping in a standing posture. FOA used a more cautious strategy by reverting the MoS earlier than YA, allowing them to increase their MoS before YA when preparing to grasp the dowel.
Assuntos
Acidentes por Quedas , Postura , Humanos , Idoso , Equilíbrio Postural , Posição Ortostática , Fatores de TempoRESUMO
Objective: Determine the reliability of three different methods of evaluating bone shortening in displaced midshaft clavicle fractures (DCMF). Method: A cross-sectional analytical study evaluated bone shortening by metric tape (MT), radiography (X-ray), and computed tomography (CT). Twenty-six men had been evaluated and used clavícula not broken as control. The collection of data was of the blind type for three specialists. Differences and reliability were analyzed with the Friedman and Kappa tests and validated with the T-test (CI: 95%; significance index p<0.05; Software "R" version 3.2.2). Results: The MT measurements (control) showed abnormal distribution and significant statistical difference concerning the imaging tests (p=0.000008). There was a similarity between X-ray and CT and Kappa agreement of 0.65. The fractured clavicles presented similar measurements between the three methods (p=0.059), and the T-tests proved that the similarity was caused by chance or possible measurement errors. Conclusion: Measurement by metric tape showed a tendency to overestimate bone shortening. The CT showed more reliable results for the diagnosis; however, the X-ray was sufficient for decision-making by surgeons, and therefore, it is not possible to rule out the importance of this resource for DCMF. Level of Evidence IV; Case-Control Study.
Objetivo: Determinar a confiabilidade de três diferentes métodos de avaliação do encurtamento ósseo em fraturas deslocadas do eixo médio da clavícula (FDEMC). Método: Estudo analítico transversal que avaliou o encurtamento ósseo por fita métrica (FM), radiografia (X-Ray) e tomografia computadorizada (TC). Foram avaliados 26 homens utilizando a clavícula não fraturada como controle. A coleta de dados foi do tipo cega por três especialistas. As diferenças e a confiabilidade foram analisadas com os testes de Friedman e Kappa e validados com o teste T (IC:95%; índice de significância p<0,05; Software "R" versão 3.2.2). Resultados: As medidas de FM (controle), apresentaram distribuição anormal e diferença estatísfica significativa em relação aos exames de imagem (p=0,000008). Houve semelhança entre radiografia e TC, concordância Kappa 0,65. As clavículas fraturadas apresentaram medidas semelhantes entre os três métodos (p=0,059) e os testes-T comprovaram que a semelhança foi provocada casualmente ou possíveis erros de medição. Conclusão: A medição por fita métrica apresentou tendência em superestimação do encurtamento ósseo. A TC apresentou resultados mais confiáveis para o diagnóstico, contudo, a radiografia foi suficiente para tomada de decisão dos cirurgiões e por isso, não é possível descartar a importância deste recurso para FDEMC. Nível de Evidência IV; Estudo Caso Controle.
RESUMO
We determined beta-band intermuscular (IMC) and corticomuscular coherence (CMC) as a function of age and walking balance difficulty. Younger (n=14, 23y) and older individuals (n=19, 71y) walked 13â¯m overground, on a 6-cm-wide ribbon overground, and on a 6-cm-wide (5-cm-high) beam. Walking distance as a proxy for walking balance and speed were computed. CMC was estimated between electroencephalographic signal at Cz electrode and surface electromyographic signals of seven leg muscles, while IMC was calculated in four pairs of leg muscles, during stance and swing gait phases. With increasing difficulty, walking balance decreased in old individuals and speed decreased gradually independent of age. Beam walking increased IMC, while age increased IMC in proximal muscle pairs, and decreased IMC in distal muscle pairs. Age and difficulty increased CMC independent of gait phases. Concluding, CMC and IMC increased with walking balance difficulty and age, except for distal muscle pairs, which had lower IMC with age. These findings suggest an age-related increase in corticospinal involvement in the neural control of walking balance. DATA AVAILABILITY: The datasets used in this study are available from the corresponding author upon reasonable request.
Assuntos
Envelhecimento , Eletromiografia , Músculo Esquelético , Equilíbrio Postural , Caminhada , Humanos , Idoso , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Masculino , Equilíbrio Postural/fisiologia , Envelhecimento/fisiologia , Feminino , Adulto Jovem , Marcha/fisiologia , Eletroencefalografia , AdultoRESUMO
AIM: To assess the adaptive response of older adults with a history of falls in a single Perturbation-Based Balance Training (PBT) session by examining the margin of stability (MoS) and the number of falls. METHODS: Thirty-two older adults with a history of falls underwent a treadmill walking session lasting 20-25 min. During the PBT protocol, participants experienced 24 unexpected perturbations delivered in two ways: acceleration or deceleration of the treadmill belt, with 12 perturbations in each direction. The MoS in the anteroposterior direction was assessed for the first and last perturbations of the session, during the perturbation step (N) and the recovery step (REC), along with the number of falls during the training session. RESULTS: There was no statistically significant difference in MoS between the first and last perturbations (acceleration and deceleration) for steps N and REC. Regarding the number of falls, a significant reduction was found when comparing the first half with the second half of the training session (p = .033). There were 13 falls in the first half and only three in the second half of the PBT session. CONCLUSION: Older adults with a history of falls exhibited an adaptive response with a reduction in the number of falls during a single session of PBT despite not showing changes in the MoS.
RESUMO
OBJECTIVE: to evaluate three methods of nasogastric tube fixation in terms of adhesion, displacement and skin integrity. METHOD: ex vivo study, with a sample of 30 experimental noses (10 for each type of fixation), developed with porcine skin, based on the average measurements of the human nose, in which 14-gauge polyvinyl chloride probes were inserted and 2 methods of fixation with adhesive tape (Fixation A and B) and one with an industrial device (Fixation C) were used. Each group was exposed to traction of 50, 100 and 500g sequentially over 12 and 24 hours, testing: adhesion capacity, probe displacement and skin integrity. The Chi-square test of independence was calculated for nominal variables and Student's t-tests and analysis of variance (p< 0.05) for rational variables. RESULTS: fixation B showed lower adhesion capacity (p <0.001) when compared to the other two fixations. A mean displacement of 52.17 mm was observed in the probes fixed by methods A and B and a greater occurrence of lesions associated with fixations A and C (p = 0.001). CONCLUSION: the results show complications related to the fixations: lack of adhesion, displacement of the probe and skin lesions, drawing attention to the complexity of the procedure.