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1.
Nutrients ; 13(8)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34444861

RESUMO

So far, there is no consistent and convincing theory explaining the pathogenesis of migraines. Vascular disorders, the effect of oxidative stress on neurons, and the contribution of magnesium-calcium deficiencies in triggering cortical depression and abnormal glutaminergic neurotransmission are taken into account. However, there are no reliable publications confirming the role of dietary deficits of magnesium and latent tetany as factors triggering migraine attacks. The aim of the study was to evaluate the influence of latent magnesium deficiency assessed with the electrophysiological tetany test on the course of migraine. The study included: a group of 35 patients (29 women and six men; in mean age 41 years) with migraine and a control group of 24 (17 women and seven men; in mean age 39 years) healthy volunteers. Migraine diagnosis was based on the International Headache Society criteria, 3rd edition. All patients and controls after full general and neurological examination were subjected to a standard electrophysiological ischemic tetany test. Moreover, the level of magnesium in blood serum was tested and was in the normal range in all patients. Then, the incidence of a positive tetany EMG test results in the migraine group and the results in the subgroups with and without aura were compared to the results in the control group. Moreover, the relationship between clinical markers of spasmophilia and the results of the tetany test was investigated in the migraine group. As well as the relationship between migraine frequency and tetany test results. There was no statistically significant difference in the occurrence of the electrophysiological exponent of spasmophilia between the migraine and control group. Neither correlation between the occurrence of clinical symptoms nor the frequency of migraine attacks and the results of the tetany test was stated (p > 0.05). However, there was an apparent statistical difference between the subgroup of migraine patients with aura in relation to the control group (p < 0.05). The result raises hope to find a trigger for migraine attacks of this clinical form, the more that this factor may turn out to be easy to supplement with dietary supplementation.


Assuntos
Eletromiografia/métodos , Deficiência de Magnésio/fisiopatologia , Transtornos de Enxaqueca/etiologia , Período Refratário Eletrofisiológico , Tetania/fisiopatologia , Adulto , Estudos de Casos e Controles , Causalidade , Membrana Celular/fisiologia , Feminino , Humanos , Magnésio/sangue , Deficiência de Magnésio/complicações , Deficiência de Magnésio/diagnóstico , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/sangue , Estado Nutricional , Potássio/sangue , Tetania/complicações , Tetania/diagnóstico , Adulto Jovem
2.
Nat Commun ; 12(1): 4509, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301949

RESUMO

The capacity of the brain to encode multiple types of sensory input is key to survival. Yet, how neurons integrate information from multiple sensory pathways and to what extent this influences behavior is largely unknown. Using two-photon Ca2+ imaging, optogenetics and electrophysiology in vivo and in vitro, we report the influence of auditory input on sensory encoding in the somatosensory cortex and show its impact on goal-directed behavior. Monosynaptic input from the auditory cortex enhanced dendritic and somatic encoding of tactile stimulation in layer 2/3 (L2/3), but not layer 5 (L5), pyramidal neurons in forepaw somatosensory cortex (S1). During a tactile-based goal-directed task, auditory input increased dendritic activity and reduced reaction time, which was abolished by photoinhibition of auditory cortex projections to forepaw S1. Taken together, these results indicate that dendrites of L2/3 pyramidal neurons encode multisensory information, leading to enhanced neuronal output and reduced response latency during goal-directed behavior.


Assuntos
Potenciais de Ação/fisiologia , Córtex Auditivo/fisiologia , Dendritos/fisiologia , Células Piramidais/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Córtex Auditivo/citologia , Estimulação Elétrica , Eletromiografia/métodos , Objetivos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Optogenética/métodos , Técnicas de Patch-Clamp , Células Piramidais/citologia , Córtex Somatossensorial/citologia , Tato/fisiologia
3.
Nat Commun ; 12(1): 4646, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330901

RESUMO

Microglia are important for brain homeostasis and immunity, but their role in regulating vigilance remains unclear. We employed genetic, physiological, and metabolomic methods to examine microglial involvement in the regulation of wakefulness and sleep. Microglial depletion decreased stable nighttime wakefulness in mice by increasing transitions between wakefulness and non-rapid eye movement (NREM) sleep. Metabolomic analysis revealed that the sleep-wake behavior closely correlated with diurnal variation of the brain ceramide, which disappeared in microglia-depleted mice. Ceramide preferentially influenced microglia in the thalamic reticular nucleus (TRN), and local depletion of TRN microglia produced similar impaired wakefulness. Chemogenetic manipulations of anterior TRN neurons showed that they regulated transitions between wakefulness and NREM sleep. Their firing capacity was suppressed by both microglial depletion and added ceramide. In microglia-depleted mice, activating anterior TRN neurons or inhibiting ceramide production both restored stable wakefulness. These findings demonstrate that microglia can modulate stable wakefulness through anterior TRN neurons via ceramide signaling.


Assuntos
Potenciais de Ação/fisiologia , Neurônios GABAérgicos/fisiologia , Microglia/fisiologia , Sono/fisiologia , Núcleos Talâmicos/fisiologia , Vigília/fisiologia , Algoritmos , Animais , Eletroencefalografia/métodos , Eletromiografia/métodos , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Modelos Neurológicos , Núcleos Talâmicos/citologia
4.
Toxins (Basel) ; 13(5)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067540

RESUMO

Botulinum toxin-A (BoNT-A) blocks acetylcholine release at the neuromuscular junction (NMJ) and is widely used for neuromuscular disorders (involuntary spasms, dystonic disorders and spasticity). However, its therapeutic effects are usually measured by clinical scales of questionable validity. Single-fiber electromyography (SFEMG) is a sensitive, validated diagnostic technique for NMJ impairment such as myasthenia. The jitter parameter (µs) represents the variability of interpotential intervals of two muscle fibers from the same motor unit. This narrative review reports SFEMG use in BoNT-A treatment. Twenty-four articles were selected from 175 eligible articles searched in Medline/Pubmed and Cochrane Library from their creation until May 2020. The results showed that jitter is sensitive to early NMJ modifications following BoNT-A injection, with an increase in the early days' post-injection and a peak between Day 15 and 30, when symptoms diminish or disappear. The reappearance of symptoms accompanies a tendency for a decrease in jitter, but always precedes its normalization, either delayed or nonexistent. Increased jitter is observed in distant muscles from the injection site. No dose effect relationship was demonstrated. SFEMG could help physicians in their therapeutic evaluation according to the pathology considered. More data are needed to consider jitter as a predictor of BoNT-A clinical efficacy.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Eletromiografia/métodos , Fármacos Neuromusculares/farmacologia , Inibidores da Liberação da Acetilcolina , Humanos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Doenças Neuromusculares/tratamento farmacológico , Doenças Neuromusculares/fisiopatologia , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/metabolismo
6.
J Neuroeng Rehabil ; 18(1): 87, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034762

RESUMO

BACKGROUND: Despite important advancements in control and mechatronics of myoelectric prostheses, the communication between the user and his/her bionic limb is still unidirectional, as these systems do not provide somatosensory feedback. Electrotactile stimulation is an attractive technology to close the control loop since it allows flexible modulation of multiple parameters and compact interface design via multi-pad electrodes. However, the stimulation interferes with the recording of myoelectric signals and this can be detrimental to control. METHODS: We present a novel compact solution for simultaneous recording and stimulation through dynamic blanking of stimulation artefacts. To test the system, a feedback coding scheme communicating wrist rotation and hand aperture was developed specifically to stress the myoelectric control while still providing meaningful information to the subjects. Ten subjects participated in an experiment, where the quality of closed-loop myoelectric control was assessed by controlling a cursor in a two degrees of freedom target-reaching task. The benchmark performance with visual feedback was compared to that achieved by combining visual feedback and electrotactile stimulation as well as by using electrotactile feedback only. RESULTS: There was no significant difference in performance between visual and combined feedback condition with regards to successfully reached targets, time to reach a target, path efficiency and the number of overshoots. Therefore, the quality of myoelectric control was preserved in spite of the stimulation. As expected, the tactile condition was significantly poorer in completion rate (100/4% and 78/25% for combined and tactile condition, respectively) and time to reach a target (9/2 s and 13/4 s for combined and tactile condition, respectively). However, the performance in the tactile condition was still good, with no significant difference in path efficiency (38/8%) and the number of overshoots (0.5/0.4 overshoots), indicating that the stimulation was meaningful for the subjects and useful for closed-loop control. CONCLUSIONS: Overall, the results demonstrated that the developed system can provide robust closed-loop control using electrotactile stimulation. The system supports different encoding schemes and allows placing the recording and stimulation electrodes next to each other. This is an important step towards an integrated solution where the developed unit will be embedded into a prosthetic socket.


Assuntos
Algoritmos , Artefatos , Membros Artificiais , Desenho de Prótese , Interface Usuário-Computador , Adulto , Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos , Eletromiografia/métodos , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Masculino , Tato/fisiologia
7.
Muscle Nerve ; 64(2): 190-198, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33974714

RESUMO

INTRODUCTION/AIMS: Clinical trials addressing treatments for Duchenne muscular dystrophy (DMD) require reliable and valid measurement of muscle contractile function across all disease severity levels. In this work we aimed to evaluate a protocol combining voluntary and evoked contractions to measure strength and excitability of wrist extensor muscles for safety, feasibility, reliability, and discriminant validity between males with DMD and controls. METHODS: Wrist extensor muscle strength and excitability were assessed in males with DMD (N = 10; mean ± standard deviation: 15.4 ± 5.9 years of age), using the Brooke Upper Extremity Rating Scale (scored 1-6), and age-matched healthy male controls (N = 15; 15.5 ± 5.0 years of age). Torque and electromyographic (EMG) measurements were analyzed under maximum voluntary and stimulated conditions at two visits. RESULTS: A protocol of multiple maximal voluntary contractions (MVCs) and evoked twitch contractions was feasible and safe, with 96% of the participants completing the protocol and having a less than 7% strength decrement on either measure for both DMD patients and controls (P ≥ .074). Reliability was excellent for voluntary and evoked measurements of torque and EMG (intraclass correlation coefficient [ICC] over 0.90 and over 0.85 within and between visits, respectively). Torque, EMG, and timing of twitch-onset measurements discriminated between DMD and controls (P < .001). Twitch contraction time did not differ significantly between groups (P = .10). DISCUSSION: Findings from this study show that the protocol is a safe, feasible, reliable, and a valid method to measure strength and excitability of wrist extensors in males with DMD.


Assuntos
Contração Muscular/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/fisiopatologia , Adolescente , Adulto , Criança , Eletromiografia/métodos , Estudos de Viabilidade , Humanos , Contração Isométrica/fisiologia , Masculino , Adulto Jovem
8.
J Neuroeng Rehabil ; 18(1): 74, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947410

RESUMO

BACKGROUND: The key challenge to constructing functional corticomuscular coupling (FCMC) is to accurately identify the direction and strength of the information flow between scalp electroencephalography (EEG) and surface electromyography (SEMG). Traditional TE and TDMI methods have difficulty in identifying the information interaction for short time series as they tend to rely on long and stable data, so we propose a time-delayed maximal information coefficient (TDMIC) method. With this method, we aim to investigate the directional specificity of bidirectional total and nonlinear information flow on FCMC, and to explore the neural mechanisms underlying motor dysfunction in stroke patients. METHODS: We introduced a time-delayed parameter in the maximal information coefficient to capture the direction of information interaction between two time series. We employed the linear and non-linear system model based on short data to verify the validity of our algorithm. We then used the TDMIC method to study the characteristics of total and nonlinear information flow in FCMC during a dorsiflexion task for healthy controls and stroke patients. RESULTS: The simulation results showed that the TDMIC method can better detect the direction of information interaction compared with TE and TDMI methods. For healthy controls, the beta band (14-30 Hz) had higher information flow in FCMC than the gamma band (31-45 Hz). Furthermore, the beta-band total and nonlinear information flow in the descending direction (EEG to EMG) was significantly higher than that in the ascending direction (EMG to EEG), whereas in the gamma band the ascending direction had significantly higher information flow than the descending direction. Additionally, we found that the strong bidirectional information flow mainly acted on Cz, C3, CP3, P3 and CPz. Compared to controls, both the beta-and gamma-band bidirectional total and nonlinear information flows of the stroke group were significantly weaker. There is no significant difference in the direction of beta- and gamma-band information flow in stroke group. CONCLUSIONS: The proposed method could effectively identify the information interaction between short time series. According to our experiment, the beta band mainly passes downward motor control information while the gamma band features upward sensory feedback information delivery. Our observation demonstrate that the center and contralateral sensorimotor cortex play a major role in lower limb motor control. The study further demonstrates that brain damage caused by stroke disrupts the bidirectional information interaction between cortex and effector muscles in the sensorimotor system, leading to motor dysfunction.


Assuntos
Algoritmos , Eletroencefalografia/métodos , Eletromiografia/métodos , Acidente Vascular Cerebral/fisiopatologia , Interface Usuário-Computador , Idoso , Simulação por Computador , Retroalimentação Sensorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Músculo Esquelético/fisiologia , Projetos Piloto
9.
J Neuroeng Rehabil ; 18(1): 75, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957953

RESUMO

BACKGROUND: Falls commonly occur due to losses of balance associated with vertical body movements (e.g. reacting to uneven ground, street curbs). Research, however, has focused on horizontal perturbations, such as forward and backward translations of the standing surface. This study describes and compares muscle activation patterns following vertical and horizontal perturbations during standing and walking, and investigates the role of vision during standing postural responses. METHODS: Fourteen healthy participants (ten males; 27±4 years-old) responded to downward, upward, forward, and backward perturbations while standing and walking in a virtual reality (VR) facility containing a moveable platform with an embedded treadmill; participants were also exposed to visual perturbations in which only the virtual scenery moved. We collected bilateral surface electromyography (EMG) signals from 8 muscles (tibialis anterior, rectus femoris, rectus abdominis, external oblique, gastrocnemius, biceps femoris, paraspinals, deltoids). Parameters included onset latency, duration of activation, and activation magnitude. Standing perturbations comprised dynamic-camera (congruent), static-camera (incongruent) and eyes-closed sensory conditions. ANOVAs were used to compare the effects of perturbation direction and sensory condition across muscles. RESULTS: Vertical perturbations induced longer onset latencies and shorter durations of activation with lower activation magnitudes in comparison to horizontal perturbations (p<0.0001). Downward perturbations while standing generated earlier activation of anterior muscles to facilitate flexion (for example, p=0.0005 and p=0.0021 when comparing the early activators, rectus femoris and tibialis anterior, to a late activator, the paraspinals), whereas upward perturbations generated earlier activation of posterior muscles to facilitate extension (for example, p<0.0001 and p=0.0004, when comparing the early activators, biceps femoris and gastrocnemius, to a late activator, the rectus abdominis). Static-camera conditions induced longer onset latencies (p=0.0085 and p<0.0001 compared to eyes-closed and dynamic-camera conditions, respectively), whereas eyes-closed conditions induced longer durations of activation (p=0.0001 and p=0.0008 compared to static-camera and dynamic-camera, respectively) and larger activation magnitudes. During walking, downward perturbations promptly activated contralateral trunk and deltoid muscles (e.g., p=0.0036 for contralateral deltoid versus a late activator, the ipsilateral tibialis anterior), and upward perturbations triggered early activation of trunk flexors (e.g., p=0.0308 for contralateral rectus abdominis versus a late activator, the ipsilateral gastrocnemius). Visual perturbations elicited muscle activation in 67.7% of trials. CONCLUSION: Our results demonstrate that vertical (vs. horizontal) perturbations generate unique balance-correcting muscle activations, which were consistent with counteracting vertical body extension induced by downward perturbations and vertical body flexion induced by upward perturbations. Availability of visual input appears to affect response efficiency, and incongruent visual input can adversely affect response triggering. Our findings have clinical implications for the design of robotic exoskeletons (to ensure user safety in dynamic balance environments) and for perturbation-based balance and gait rehabilitation.


Assuntos
Músculo Esquelético/fisiologia , Equilíbrio Postural/fisiologia , Caminhada/fisiologia , Adulto , Eletromiografia/métodos , Feminino , Humanos , Masculino , Postura/fisiologia
10.
Muscle Nerve ; 64(1): 104-108, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33961288

RESUMO

INTRODUCTION/AIMS: Temporary vocal fold injection (VFI) is a common treatment for acute and subacute vocal fold paralysis (VFP). Laryngeal electromyography (LEMG) is useful for diagnosing neurogenic causes of VFP. This study evaluated whether the presence of VFI material prevents interpretation of LEMG in patients with acute and subacute VFP. METHODS: Patients with acute and subacute unilateral VFP (onset ≤6 mo) who underwent temporary VFI within 3 mo preceding LEMG were evaluated. A matched control group that did not undergo VFI was also studied. The LEMG team (laryngologist and electromyographer) performed and interpreted LEMG using a pre-specified protocol, including qualitative and quantitative motor unit analysis. RESULTS: Eighteen patients with VFI underwent LEMG successfully with interpretation of spontaneous activity and motor unit recruitment. Fourteen patients were seen in follow-up to determine accuracy of established LEMG prognosis. Seven of seven subjects with poor LEMG prognosis did not recover vocal fold motion. Five of seven subjects with fair LEMG prognosis recovered vocal fold motion. Findings were similar for the control group. DISCUSSION: VFI augmentation material did not prevent interpretation of meaningful LEMG data in patients with acute and subacute VFP, and accurate prognoses of vocal fold motion recovery were established.


Assuntos
Celulase/administração & dosagem , Eletromiografia/métodos , Paralisia das Pregas Vocais/diagnóstico , Paralisia das Pregas Vocais/fisiopatologia , Prega Vocal/efeitos dos fármacos , Prega Vocal/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Laringe/efeitos dos fármacos , Laringe/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Acta Orthop Traumatol Turc ; 55(2): 181-183, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33847583

RESUMO

The posterior interosseous nerve (PIN) is the terminal branch of the radial nerve. The symptoms of PIN palsy vary markedly according to its types. In this report, we present the case of a 61-years-old male patient with an unusual manifestation of non-traumatic novel type of PIN palsy. A complicated course was involved in the diagnosis of this disease. The operation was performed after verification of PIN palsy. Recovery of symptoms was observed in a follow-up conducted three years later. Additionally, the electromyography examination returned to normal.


Assuntos
Descompressão Cirúrgica/métodos , Síndromes de Compressão Nervosa , Nervo Radial , Neuropatia Radial , Eletromiografia/métodos , Antebraço/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/fisiopatologia , Síndromes de Compressão Nervosa/cirurgia , Paralisia/diagnóstico , Paralisia/etiologia , Paralisia/cirurgia , Nervo Radial/lesões , Nervo Radial/fisiopatologia , Neuropatia Radial/diagnóstico , Neuropatia Radial/fisiopatologia , Neuropatia Radial/cirurgia , Recuperação de Função Fisiológica , Resultado do Tratamento
12.
J Manipulative Physiol Ther ; 44(3): 205-220, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33902943

RESUMO

OBJECTIVE: The present study aimed to investigate the electromyographic (EMG) indices of muscle fatigue along with biochemical marker of fatigue-that is, blood lactate-during a dynamic fatigue protocol in individuals with type 2 diabetes mellitus (T2DM) vs a healthy control group. Secondarily, it aimed to examine the association between EMG indices of muscle fatigue and blood lactate in these patients. METHODS: Thirty-four participants took part in the study: 19 individuals with T2DM (age, 53.5 ± 6.85 years) and 15 age-matched healthy controls (age, 50.2 ± 3.55 years). Participants performed a dynamic fatigue protocol consisting of 5 sets of 10 repetitions each at an intensity of the 10-repetition maximum. Surface EMG of the vastus medialis and vastus lateralis muscles was recorded during the dynamic fatigue protocol, and EMG indices such as median frequency (MF), slope of MF (MFslope), Dimitrov muscle fatigue spectral index, and root-mean-square were evaluated for each contraction across all the 5 sets. Blood lactate concentrations were also assessed 3 times during the fatigue protocol. RESULTS: Findings revealed that EMG muscle fatigue indices such as MF, MFslope, and Dimitrov muscle fatigue spectral index were significantly altered in individuals with T2DM vs healthy individuals across the sets and repetitions for both the vastus medialis (P < .001) and vastus lateralis muscles (P < .001). There was a significantly greater rise in blood lactate in individuals with T2DM than in healthy individuals (P < .001), which was not found to be associated with changes in EMG indices of muscle fatigue. CONCLUSION: Findings suggest the existence of significantly greater fatigue in the knee extensor muscles of individuals with T2DM than healthy individuals.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Estudos de Casos e Controles , Eletromiografia/métodos , Humanos , Articulação do Joelho/fisiologia , Masculino , Pessoa de Meia-Idade , Resistência Física/fisiologia , Amplitude de Movimento Articular
13.
Radiology ; 300(1): 141-151, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33847517

RESUMO

Background MRI, Tinel test, and rhomboid electromyography (EMG) can be used to predict whether C5 spinal nerve stumps are healthy and eligible for grafting in acute adult brachial plexus injuries, but their comparative diagnostic efficacies have not been evaluated. Purpose To compare diagnostic performances of MRI, Tinel test, and rhomboid EMG in predicting healthy C5 spinal nerve stumps that are eligible for grafting. Materials and Methods This retrospective study included consecutive adult patients with acute brachial plexus injury who underwent microreconstructions between January 2008 and December 2018. Healthy C5 spinal nerve stumps eligible for grafting with preceding normal intradural nerve rootlets were diagnosed by an experienced neuroradiologist using an avulsion severity score system based on fast imaging employing steady-state acquisition or FIESTA neurography, which separates intradural nerve rootlets into normal, partial mild, severe, and complete avulsions. Tinel test and rhomboid EMG results were assessed by an experienced nerve surgeon and neurologist, respectively. The accuracy, sensitivity, and specificity of the three tests were compared using microdissection as the reference standard. P < .05 was considered to indicate a significant difference. Results A total of 251 patients (mean age, 31 years ± 13 [standard deviation]; 217 men) with brachial plexus injuries who had -undergone MRI (n = 251), Tinel test (n = 235), rhomboid EMG (n = 181) and MRI, Tinel test, and EMG (n = 172) were -included. Accuracy, sensitivity, and specificity, respectively, in predicting healthy C5 spinal nerve stumps eligible for grafting were 93% (233 of 251), 84% (58 of 69), and 96% (175 of 182) for MRI; 59% (139 of 235), 56% (37 of 66), and 60% (102 of 169) for Tinel test; and 39% (71 of 181), 85% (43 of 50), and 21% (28 of 131) for rhomboid EMG. MRI (area under the receiver operating characteristic curve [AUC], 0.90; P < .001) -outperformed MRI and Tinel test (AUC, 0.74), Tinel test (AUC, 0.59), and rhomboid EMG (AUC, 0.53). Conclusion MRI performed best in the prediction of healthy graftable C5 spinal nerve stumps in acute adult brachial plexus injuries. © RSNA, 2021 Online supplemental material is available for this article.


Assuntos
Neuropatias do Plexo Braquial/diagnóstico por imagem , Neuropatias do Plexo Braquial/cirurgia , Eletromiografia/métodos , Imageamento por Ressonância Magnética/métodos , Raízes Nervosas Espinhais/diagnóstico por imagem , Raízes Nervosas Espinhais/cirurgia , Adulto , Plexo Braquial/diagnóstico por imagem , Plexo Braquial/cirurgia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
14.
Muscle Nerve ; 64(1): 86-89, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33822375

RESUMO

INTRODUCTION/AIMS: The virtual cathode (VC) is a site near the anode where the nerve can be stimulated. Costimulation of neighboring nerves via the VC can affect recording and interpretation of responses. Hence, it is important to teach trainees the concept of the VC. The VC has been demonstrated previously with subtle changes in response latency, amplitude, and shape. Herein we describe an experiment that simply demonstrates a VC with its effects recognizable by gross changes in waveforms. METHODS: Compound muscle action potentials of the abductor pollicis brevis were recorded using various placements of the cathode and anode at different stimulus intensity levels. Studies were performed in nine healthy subjects. RESULTS: Three patterns were observed that demonstrated no stimulation, partial stimulation, and complete nerve stimulation by the VC. Partial stimulation yielded responses with long duration and low amplitude. Response patterns also depended on stimulus strength and proximity of the nerve from the skin surface. DISCUSSION: This experiment demonstrates that nerve stimulation can occur near the anode when high-intensity stimulus is used. It also illustrates collision of action potentials. This exercise can help trainees understand potential pitfalls in nerve conduction studies, especially at very proximal stimulation sites or when high stimulus intensity is used.


Assuntos
Competência Clínica , Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos , Nervo Mediano/fisiologia , Condução Nervosa/fisiologia , Potenciais de Ação/fisiologia , Adulto , Idoso , Eletrodos , Eletromiografia/instrumentação , Eletromiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Exame Neurológico/instrumentação , Exame Neurológico/métodos
15.
Clin Geriatr Med ; 37(2): 209-221, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33858605

RESUMO

Nerve conduction studies and electromyography are useful diagnostic tools that neurologists use to diagnose diseases of the peripheral nerves, neuromuscular junction, and muscles. These tests are considered an extension of clinical history and examination, and their results should always be interpreted with the clinical context. Neuromuscular diseases are common and affect a large proportion of the elderly population. With an aging population in expansion, these diseases are expected to become even more prevalent. It is important to highlight the basics of electrophysiology and provide a reference for providers who are planning to send their patients to electromyographers for these studies.V.


Assuntos
Eletrodiagnóstico , Eletromiografia/métodos , Polineuropatias/diagnóstico , Neuropatias Ulnares/diagnóstico , Síndrome do Túnel Carpal , Humanos , Radiculopatia
16.
NeuroRehabilitation ; 48(3): 345-351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814474

RESUMO

BACKGROUND: Electromyographic biofeedback (EMG BF) training is an effective method of promoting motor learning and control in neurorehabilitation, but its effect on quadriceps femoris muscle in individuals with spinal cord injury (SCI) is unknown. OBJECTIVE: The aim of the study was to investigate the therapeutic effect of EMG BF training on motor function of quadriceps femoris in patients with incomplete SCI. METHODS: Thirty-three incomplete paraplegic patients with quadriceps femoris strength ranging grade 1 to grade 3 less than 6 months post-injury were enrolled. Control group (n = 16) received conventional physical therapy to enhance quadriceps femoris strength, while intervention group (n = 17) was treated with conventional physical therapy and EMG BF training. All received treatment once a day for 30 days. Surface electromyograph (sEMG), muscle strength and thigh circumference size were assessed to evaluate motor function of quadriceps femoris. Activities of daily living (ADL) was evaluated by Modified Barthel Index (MBI). All the measures evaluated three times in total. RESULTS: Compared to the control group, intervention group significantly improved on sEMG values and strength of quadriceps femoris (PsEMG < 0.001, Pstrength < 0.05). sEMG values of quadriceps femoris increased earlier than strength of quadriceps femoris in intervention group (Prest = 0.07, Pactive = 0.031). There were no statistical differences in thigh circumference size and ADL scores between groups (Pthigh > 0.05, PADL = 0.423). CONCLUSIONS: EMG BF training appeared to be a useful tool to enhance motor function of quadriceps femoris in patients with incomplete SCI. sEMG could quantify the changes of single muscle myodynamia precisely before visible or touchable changes occur.


Assuntos
Eletromiografia/métodos , Retroalimentação Fisiológica , Reabilitação Neurológica/métodos , Músculo Quadríceps/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Atividades Cotidianas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular
17.
Life Sci ; 277: 119492, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33864819

RESUMO

AIMS: Non-invasive and simultaneous recording of gastrointestinal (GI) activity during stress induction is still an unexplored field. In our previous investigation, the stress-induced alteration of the gastrointestinal tract was explored in rats. Our aims were to expand our previous rat experiment and to induce stress response in rats (Study 1) and humans (Study 2) to detect the GI tract activity, heart rate and body temperature. MATERIALS AND METHODS: In the preclinical sample, acute stress was induced by immobilization in Sprague-Dawley rats (N = 10). Acute stress response was generated by the Trier Social Stress Test among healthy volunteers (N = 16). Detection of acute stress was measured by using smooth muscle electromyography, which recorded the myoelectric waves of the gastrointestinal tract (stomach, ileum and colon) simultaneously with heart rate and body temperature in rats and humans. KEY FINDINGS: The myoelectric waves of the stomach, the cecum and the ileum increased during immobilization in rats, rising in parallel with heart rate and the dermal temperature of the abdominal surface. The same alterations were found during the stress period among humans, except in the case of the colon, where no change was detected. SIGNIFICANCE: The crucial role of the GI tract in stress response was revealed by translating the outcome of basic research into human results. The similar GI alterations during stress in rats and humans underpin the robustness of our findings. In summary, our preliminary translational-based study can serve as an appropriate basis for further human studies.


Assuntos
Trato Gastrointestinal/fisiologia , Miócitos de Músculo Liso/metabolismo , Estresse Fisiológico/fisiologia , Adulto , Animais , Ceco/fisiologia , Colo/fisiologia , Eletromiografia/métodos , Feminino , Motilidade Gastrointestinal/fisiologia , Voluntários Saudáveis , Humanos , Íleo/fisiologia , Masculino , Músculo Liso/fisiologia , Ratos , Ratos Sprague-Dawley , Estômago/fisiologia
18.
Medicine (Baltimore) ; 100(14): e25252, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33832085

RESUMO

RATIONALE: Wrist-hand extension function rehabilitation is a vital and difficult part of hand function recovery in spastic stroke patients. Although botulinum toxin type A (BoNTA) injection plus post injection therapy was applied to the wrist-hand rehabilitation in previous reports, conclusion was inconsistent in promoting function. For this phenomenon, proper selection of patients for BoNTA injection and correct choice of post-injection intervention could be the crucial factors for the function recovery. PATIENT CONCERNS: We reported a 46-year-old male suffered a spastic hemiplegia with wrist- hand extension deficit. DIAGNOSES: Computed tomography showed cerebral hemorrhage in the left basal ganglia region. INTERVENTIONS: Four hundred units of BoNTA were injected into the spasticity flexors, and four-week post injection surface electromyography (sEMG) biofeedback therapy was applied to the patient. OUTCOMES: The patient exhibited post-intervention improvement in wrist-hand extensors performance (strength, range of motion, sEMG signals), the flexors spasticity, and upper extremity function. LESSONS: The present case showed that 4-week of BoNTA injection plus sEMG biofeedback exercise improved the performance and function of wrist-hand extensors in the patient for short- and long-term. Proper selection of patients for BoNTA injection and correct choice of post injection exercise could play a vital role in the hand rehabilitation for patient with spastic hemiplegia.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Mãos , Espasticidade Muscular/tratamento farmacológico , Punho , Eletromiografia/métodos , Hemiplegia/complicações , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Espasticidade Muscular/reabilitação
19.
J Electromyogr Kinesiol ; 58: 102548, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33838590

RESUMO

There is a growing interest in decomposing high-density surface electromyography (HDsEMG) into motor unit spike trains to improve knowledge on the neural control of muscle contraction. However, the reliability of decomposition approaches is sometimes questioned, especially because they require manual editing of the outputs. We aimed to assess the inter-operator reliability of the identification of motor unit spike trains. Eight operators with varying experience in HDsEMG decomposition were provided with the same data extracted using the convolutive kernel compensation method. They were asked to manually edit them following established procedures. Data included signals from three lower leg muscles and different submaximal intensities. After manual analysis, 126 ± 5 motor units were retained (range across operators: 119-134). A total of 3380 rate of agreement values were calculated (28 pairwise comparisons × 11 contractions/muscles × 4-28 motor units). The median rate of agreement value was 99.6%. Inter-operator reliability was excellent for both mean discharge rate and time at recruitment (intraclass correlation coefficient > 0.99). These results show that when provided with the same decomposed data and the same basic instructions, operators converge toward almost identical results. Our data have been made available so that they can be used for training new operators.


Assuntos
Eletromiografia/normas , Potencial Evocado Motor , Músculo Esquelético/fisiologia , Adulto , Eletromiografia/métodos , Humanos , Masculino , Contração Muscular , Reprodutibilidade dos Testes
20.
Medicine (Baltimore) ; 100(17): e25698, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33907149

RESUMO

RATIONALE: Peripheral nerve injury related to vascular complications associated with extracorporeal membrane oxygenation (ECMO) is perhaps underappreciated. Compared to the well-described central nervous system complications of ECMO, brachial plexopathy and lumbosacral plexopathy have rarely been reported. We report this case to heighten awareness of lumbosacral plexus injury due to pelvic hematoma formation after ECMO. PATIENT CONCERNS: A 53-year-old woman developed a large pelvic hematoma with significant mass effect on intrapelvic structures after receiving lifesaving venoarterial ECMO for cardiogenic shock following a cardiac arrest. During her hospital course, she developed bilateral foot drop that was attributed to critical illness. Her lack of neurological recovery after 6 months prompted referral to neuromuscular medicine for consultation. DIAGNOSIS: The patient was retrospectively diagnosed with bilateral lumbosacral plexopathy due to the large pelvic hematoma. INTERVENTION: Electromyography/nerve conduction study (EMG/NCS) obtained at the time of referral to neuromuscular medicine localized her neurological deficits to the bilateral lumbosacral plexus and demonstrated no volitional motor unit action potentials in her lower leg muscles. OUTCOMES: The patient had minimal recovery of strength at the level of the ankles but was ambulatory with solid ankle-foot orthoses due to spared proximal lower extremity strength. Unfortunately, the absence of any volitionally activated motor unit action potentials in her lower leg muscles on EMG performed 6 months after the initial injury was a poor prognostic indicator for successful reinnervation and future neurological recovery. LESSONS: Neurological deficits occurring during the course of administration of ECMO require accurate localization. Neurology consultation and/or EMG/NCS may be useful if localization is not clear. Lesions localizing to the lumbosacral plexus should prompt radiographic evaluation with computed tomography of the abdomen and pelvis. Hemostasis of a retroperitoneal hematoma may be achieved with embolization. However, if neurological deficits do not improve, surgical consultation for hematoma evacuation may be warranted.


Assuntos
Oxigenação por Membrana Extracorpórea , Parada Cardíaca/cirurgia , Hematoma , Plexo Lombossacral/lesões , Pelve , Traumatismos dos Nervos Periféricos , Neuropatias Fibulares , Estado Terminal/terapia , Eletromiografia/métodos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Feminino , Parada Cardíaca/etiologia , Hematoma/complicações , Hematoma/fisiopatologia , Humanos , Pessoa de Meia-Idade , Condução Nervosa , Pelve/irrigação sanguínea , Pelve/patologia , Traumatismos dos Nervos Periféricos/diagnóstico , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Neuropatias Fibulares/diagnóstico , Neuropatias Fibulares/etiologia , Neuropatias Fibulares/fisiopatologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Prognóstico , Choque Cardiogênico/complicações
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