RESUMO
SUMMARY: The Innervation Zones (IZ) correspond to clusters of neuromuscular junctions. The traditional method of locating IZs through voluntary muscle contractions may not be feasible in individuals with motor disorders. Imposed contractions by electrostimulation are an alternative. However, there is limited evidence regarding the factors that affect inter-evaluator concordance and the number of localized IZs when using imposed contraction. The main objective of this research was to determine the effect of the amplitude of compound motor action potentials (CMAPs) containing the M-wave on inter-evaluator agreement. As a secondary objective, was investigate the effect on the number of detected IZs. Twenty-four healthy volunteers (age: 21.2 ± 1.5years, weight: 67.4 ± 13.2kg, height: 1.68 ± 0.80m) participated in the study. Electrostimulation was applied to the tibial nerve to induce contraction of the medial gastrocnemius. The IZ were identified based on the M-wave recorded through multichannel electromyography. A receiver operating characteristic (ROC) analysis was conducted to assess sensitivity and specificity in detecting the IZs. Inter-rater agreement was evaluated using a two-way mixed effects test to determine the intraclass correlation coefficients (ICC). A p-value less than 0.05 was considered statistically significant. The ROC analysis revealed that for both evaluators, a specificity of 95% was achieved with an amplitude ≥30 %. The area under the ROC curve was 0.980 [0.964, 0.996], indicating a strong influence of CMAP amplitude on detection of IZs. The highest level of agreement (ICC = 0.788 [0.713, 0.844]) among the evaluators was observed with CMAP amplitudes equal to or greater than 80 % of the maximum M-wave. The findings of this study demonstrate that both the number and the inter-evaluator concordance for detecting IZs using imposed contractions are strongly influenced by the amplitude of the M-wave. Higher M-wave amplitudes were associated with improved concordance and increased IZ detection, making it crucial to standardize amplitude settings for reliable outcomes.
Las Zonas de Inervación (IZ) corresponden a grupos de uniones neuromusculares. El método tradicional para localizar IZs mediante contracciones musculares voluntarias puede no ser factible en personas con trastornos motores. Las contracciones impuestas mediante electro estimulación son una alternativa. Sin embargo, existe poca evidencia sobre los factores que afectan la concordancia entre evaluadores y el número de IZs localizadas al usar este tipo de contracciones. El objetivo de esta investigación fue determinar el efecto de la amplitud de los potenciales de acción motores compuestos (PAMCs) que contienen la onda M sobre la concordancia entre evaluadores. Como objetivo secundario, se investigó el efecto sobre el número de IZs detectadas. Veinticuatro voluntarios sanos (edad: 21.2 ± 1.5 años, peso: 67.4 ± 13.2 kg, altura: 1.68 ± 0.80 m) participaron en el estudio. Se aplicó electroestimulación al nervio tibial para inducir la contracción del gastrocnemio medial. Las IZs se identificaron según la onda M registrada mediante electromiografía multicanal. Se realizó un análisis de curva de las característica del receptor (ROC) para evaluar la sensibilidad y especificidad en la detección de las IZs. La concordancia entre evaluadores se evaluó utilizando una prueba de efectos mixtos de dos vías para determinar los coeficientes de correlación intraclase (ICC). Se consideró un valor de p menor que 0.05 como estadísticamente significativo. El análisis ROC reveló que para ambos evaluadores se logró una especificidad del 95% con una amplitud ≥30 %. El área bajo la curva ROC fue de 0.980 [0.964, 0.996], lo que indica una fuerte influencia de la amplitud del CMAP en la detección de las IZs. El nivel más alto de concordancia (ICC = 0.788 [0.713, 0.844]) entre los evaluadores se observó con amplitudes de CMAP iguales o mayores al 80 % de la onda M máxima. Los hallazgos de este estudio demuestran que tanto el número como la concordancia entre evaluadores para detectar IZs mediante contracciones impuestas están fuertemente influenciados por la amplitud de la onda M. Las amplitudes más altas de la onda M se asociaron con una concordancia mejorada y un aumento en la detección de IZs, lo que hace crucial estandarizar los ajustes de amplitud para obtener resultados confiables.
Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Músculo Esquelético/inervação , Variações Dependentes do Observador , Curva ROC , Sensibilidade e Especificidade , Eletromiografia/métodos , Contração MuscularRESUMO
@#M-waves and F-responses were investigated before and after massage using the bipolar surface electrodes to stimulate the tibial nerve at the ankle recorded by bipolar surface electrodes from the muscle flexor hallucis in 30 children with cerebral palsy. After treatment, the amplitudes of the M-wave increased (P＜0.05 ); F-response reduced (P＜0.05 )in the lesion side. The observations were made bilaterally and the results revealed no significant differences(P＞0.05 )by comparing side to side. The latencies of Mwaves prolonged to 6.09～8. 28ms(P<0.05);F-responses 29.07～3l. 42ms(only Fn wave was P＜0.05in the lesion side). The significant efficiency was 25.93 %,the efficiency was 88.89 % except that 2 objects did not change and one continued to deteriorate. The experimental results suggest that the massage can improve the functional disorder of the skeletal muscle and the ventral horn of the spinal cord.
RESUMO
Objective To study the changes of low-frequency-component of intracranial pressure (ICP) fluctuation during intracranial hypertension. Methods 15 healthy mongrel dogs were used to make models of intracranial hypertension by arranging latex sacculus epidurally.The different amount of normal that was injected into latex sacculus led to fluctuation of ICP and alteration of intracranial volume. The pressures in ventricle and lumbar spinal canal were recorded continuously by baroceptor, and the changes of low-frequency-component of ICP fluctuation were studied by frequency-spectrum analysis. Results After increase of intracranial pressure and volume,pulse wave (M wave) with its frequency at 0.1～0.2 Hz showed continually. Conclusion Emerge of M wave may reflect some decrease of intracranial compliance and the beginning of volume compensation failure.
RESUMO
After being stimulated by the application of electroacupuncture (EA) to “KOTAN” leg point (bilaterally), chickens became sedated and showed and showed analgesia with little response to skin clamping. Following the observation of M waves of Motor nerves and evoked responses of Sensory nerves, it was found that while efferent information was temporarily inhibited during EA stimulation, afferent information was depressed during EA and the effect continued for several hours after termination of EA. It is suggested that these phenomena may be controled by neurohumoral mechanisms.