View clinical trials related to Electrical Stimulation.
Filter by:High-frequency alternating currents of greater than 1 kHz applied on peripheral nerves has been used in animal studies to produce a motor nerve block. It has been evidenced that frequencies higher than 5 kHz are necessary to produce a complete peripheral nerve block in primates, whose nerve thickness is more similar to humans.
Introduction: Neuromuscular electrical stimulation (NMES) has the purpose of generating muscle contractions to minimize muscular atrophy and to improve neuromuscular performance. NMES has been performed using monophasic or biphasic currents, applied over a nerve trunk or muscle belly, and both can generate contractions by the peripheral and central nervous system. Pulse width (wide or narrow) is an essential parameter for NMES. Although NMES studies using wide pulses have been performed with monophasic currents, it is known that this current induces discomfort during NMES. Therefore, it is necessary to analyze if biphasic currents have the same effect as monophasic currents using the same parameters. Objectives: To compare the effects of NMES with narrow and wide pulse widths associated with monophasic and biphasic currents, applied over a tibial nerve and triceps surae muscles in healthy individuals in terms of muscle fatigue, central and peripheral contribution, voluntary and evoked force and sensory discomfort. Methods: A crossover, experimental controlled and randomized study will be developed with healthy male and female (age: 18-45 years). The following dependent variables will be: amplitude of H-reflex and M-wave (single and double pulses), voluntary and evoked triceps surae muscles torque, fatigability (force time integral), perceived discomfort and neuromuscular adaptations. The independent variables will be related to current phase, pulse width and location of electrical stimulation electrodes. There will be a familiarization session followed by 9 sessions with 7 rest days between them (10 weeks). Data will be reported as mean and standard deviation (± SD). Parametric tests will be used for the normally distributed data (Shapiro-Wilk test) that show homogeneous variations (Levene test). A repeated measure mixed-model ANOVA will be performed and, in the case of major effects or significant interactions, the Tukey post-hoc test will be applied. In addition, the power and size of the effect (reported as partial eta square, partial η2) will be calculated. The significance threshold will be set at p <0.05 for all procedures. Expected results: Biphasic currents will be more comfortable and will generate less muscle fatigue when compared to monophasic currents. There will be less fatigue and greater central contribution when wider pulse currents will be applied over a nerve trunk concerning the application with a wide pulse over a muscle belly.
The aim of the present study is to investigate the possibilities of visual field enhancement with electrical stimulation (ES) as a home stimulation method, in a total of 50 patients with optical neuropathy, who have already been treated with ES in the past. Furthermore, factors responsible for response variability and treatment effectiveness are also explored: (i) the role of mental stress (or stress resilience), (ii) the status of biomarkers, such as the systemic stress hormone levels and blood supply to the eye and brain (specifically vascular dysregulation) and (iii) the influence of personality, anxiety, depression and lifestyle. The study serves to further validate this ES procedure for the treatment of visual impairment. Specifically, better efficacy, better compliance, lowest response variability are expected after long-term home use.
The aim of the study is to evaluate effects of current stimulation of the brain on vision parameters, vision-related quality of life, and physiological parameters to uncover mechanisms of vision restoration. These include EEG-spectra and coherence measures, and visual evoked potentials. The design of stimulation protocols involves an appropriate sham-stimulation condition and sufficient follow-up periods to test whether the effects are stable. This is the first application of non-invasive current stimulation for vision rehabilitation in stroke-related visual field deficits.
This study aims to evaluate on an acute session of the central and peripheral contributions of electrical stimulation on the muscle belly of the triceps surae, electrical stimulation of the tibial nerve and voluntary exercise of the triceps surae muscle, and identify responders individuals and non-responders to stimulation of the tibial nerve. Another objective of the study is to compare the effects of conventional electrical stimulation applied to the sciatic triceps muscle, tibial nerve stimulation and voluntary exercise after eight weeks of training in healthy individuals.
Introduction: The muscle contractile effectiveness is influenced by the neural activation of the motor units, as well as its architecture and the elasticity of the myotendinous junction. In addition, tendinous properties also affect the production of muscle strength and function. Neuromuscular electrical stimulation (NMES) is a wide-used tool in rehabilitation for motor relearning, to reduce muscular atrophy, pain control and to improve functional performance. Although studies have demonstrated the efficacy of NMES in various clinical situations, the best joint angle (ideal muscle length) to enhance neuromuscular and tendinous adaptations induced by NMES has to be determined. Objective: To investigate the effect of NMES on different hip and knee angles on knee extensor torque, quadriceps muscle electromyographic activity, architecture, and tendon-aponeurosis complex elongation, and tendinous properties of the patellar tendon. Material and Methods: This is a crossover study with healthy males, aged 18-35 years. The independent variables will be: 1) NMES in different lower limb positions: knee joint angulation at 20º or 60º with hip at 0º or 80º (four combinations). The dependent variables will be: knee extensor torque, surface muscle electrical activity, muscle architecture (muscle thickness, pennation angle and fascicular length), the elongation of the tendon-aponeurosis complex of the quadriceps muscle components, and the properties (stiffness, Young's modulus and cross-sectional area) of the patellar tendon. The descriptive and analytical statistics will be carried out with measures of central tendency and dispersion, inference tests, tables and graphs. The normality of the data will be verified with the Shapiro-Wilk test. For the data that present normal distribution, the Two-Way ANOVA will be applied to verify differences among the measurements, with post-hoc of Bonferroni. The non-parametric option will be the Friedman test. Correlation coefficients will be calculated using the Pearson (parametric) or Spearman (non-parametric) correlation test. The level of statistical significance will be p <0.05. Expected results: The effect of an NMES session on the neural, muscular and tendon adaptations related to the angular specificity of the hip and knee, indicating greater potential for strength and muscle mass gains, will be shown, which is fundamental in the prescription of electrostimulation in rehabilitation.
Bonestim system for osteoporosis treatment uses surface electrical stimulation of neuromuscular and skeletal tissue by multipad stimulation electrodes for inducing contractions of the spinal column muscles. The primary aim of this clinical study is to determine if the Bonestim therapy can improve bone density. A secondary aim is to determine whether the applied treatment increases postural stability and facilitation of daily life activities. Inducing of contractions of the spinal column muscles in this manner could be new treatment options for the patients with reduced mobility and the patients with serious contraindications for drugs.
The study was designed to test the following hypotheses: In patients with severe obesity, a multisite electrostimulation session (m-NMES) will induce higher changes in metabolic, inflammatory and cardiovascular parameters and higher increase in muscle strength during stimulated contractions than conventional unidirectional electrostimulation session (c-NMES). In patients with severe obesity, a six-weeks m-NMES training program will enhance cardiovascular, metabolic and inflammatory parameters.