ABSTRACT
INTRODUCTION: In this study we aimed to determine the contribution of the E2 (reference electrode) to the compound muscle action potential (CMAP) amplitude during fibular motor recording to the tibialis anterior (TA) when E2 is placed over routine referential vs. alternative sites. METHODS: The CMAP was obtained from 10 healthy subjects, using the active electrode (E1) over sites routinely used as E2 for the TA, whereas the E2 was over the contralateral knee. The same procedure was performed with the E1 over alternative E2 sites. RESULTS: Significant electrical signal was captured over routine E2 placement sites. Among the tested alternative E2 sites, the ipsilateral patella (especially its medial aspect) was the most electrically silent. DISCUSSION: Using alternative E2 sites with near isoelectric recordings can optimize near-field potential measurement in the fibular motor recording to the TA and represents a more accurate way of measuring nerve and muscle function. Muscle Nerve 59:249-253, 2019.
Subject(s)
Action Potentials/physiology , Muscle, Skeletal/physiology , Neural Conduction/physiology , Peroneal Nerve/physiology , Adult , Aged , Electric Stimulation , Electrodes , Electromyography , Female , Healthy Volunteers , Humans , Male , Middle AgedABSTRACT
INTRODUCTION: Our objective was to determine the utility of motor unit number index (MUNIX) and neurophysiological index (NI) as surrogate biomarkers of disease progression in limbs without clinical signs of lower motor neuron (LMN) involvement from patients with slowly progressive amyotrophic lateral sclerosis (ALS). METHODS: Patients with slowly progressive ALS and at least 1 clinically unaffected limb were prospectively enrolled. Clinical signs of LMN loss and results from hand-held dynamometer (HHD), revised ALS Functional Rating Scale (ALSFRS-R), mean-MUNIX (from 3 different muscles), and NI were longitudinally recorded. RESULTS: Eighteen patients with 43 presymptomatic muscles were evaluated. Twenty-seven muscles remained clinically unaffected during study, with stable ALSFRS-R subscores and HHD measures. However, a significant decline in mean-MUNIX and NI was detected. DISCUSSION: Mean-MUNIX and NI were more sensitive than clinical measures at detecting LMN loss in presymptomatic limbs from patients with slowly progressive ALS. Therefore, these electrophysiological biomarkers should be included in early study phases as meaningful outcome measures. Muscle Nerve 58: 204-212, 2018.
Subject(s)
Amyotrophic Lateral Sclerosis/pathology , Motor Neurons/pathology , Muscle Fibers, Skeletal/pathology , Action Potentials , Aged , Biomarkers , Cell Count , Disease Progression , Electrodiagnosis , Female , Hand Strength , Humans , Male , Middle Aged , Muscle Strength Dynamometer , Prospective Studies , Treatment OutcomeABSTRACT
OBJECTIVE: To describe the prevalence and severity of periodic limb movements during sleep in amyotrophic lateral sclerosis patients and to explore this fact as a predictor of severity of the condition with respect to mortality. METHODS: In this case-control study, questionnaire and polysomnographic data were analyzed from 35 amyotrophic lateral sclerosis patients. Controls were matched by age, genre, and body mass index. A Kaplan-Meier curve was used to compare the survival time of patients with periodic limb movements of sleep index below or above 5. RESULTS: The number of amyotrophic lateral sclerosis patients with an index greater than five was higher than controls (19 (53%) versus 4 (11%); p<0.0001), and the mean index was higher (23.55±40.07 versus 3.28±8.96; p=0.0009). Earlier mortality was more common in patients with more than five periodic limb movements per hour of sleep than patients with less than five periodic limb movements per hour of sleep (7/19 (37%) versus 1/16 (6%); p=0.04) in this group of patients that had a mean survival of 33 months. CONCLUSIONS: There were more periodic limb movements of sleep in amyotrophic lateral sclerosis patients than in the control population. The higher number of these movements in amyotrophic lateral sclerosis patients correlates with disease severity and may suggest poor survival.
OBJETIVO:Descrever a prevalência e a severidade dos movimentos periódicos de membros durante o sono nos pacientes com esclerose lateral amiotrófica e explorar isso como um preditor de severidade da doença e mortalidade. MÉTODOS: Estudo caso controle em que foram analisados 35 pacientes por questionários e polissonografia. Os controles foram pareados por idade, gênero, e índice de massa corporal. Uma curva de Kaplan-Meier foi usada para comparar o tempo de sobrevida em pacientes com índice de movimento periódico de membros durante o sono acima e abaixo de 5. RESULTADOS: O número de pacientes com esclerose lateral amiotrófica com índice de movimentos periódicos de membros durante o sono acima de cinco foi maior do que os controles (19 (53%) versus 4 (11%); p<0,0001) e a média do índice de movimentos periódicos de membros durante o sono também foi maior no grupo dos pacientes (23,55±40,07 versus 3,28±8,96; p=0,0009). A mortalidade precoce foi mais comum em pacientes com mais que cinco movimentos durante o sono por hora do que pacientes com menos do que cinco movimentos durante o sono por hora (7/19 (37%) versus 1/16 (6%); p=0,04). Nesse grupo, os pacientes tiveram sobrevida média de 33 meses. CONCLUSÃO:Houve um maior número de movimentos periódicos de membros durante o sono em pacientes com esclerose lateral amiotrófica do que na população controle. O maior número de movimentos periódicos de membros durante o sono em pacientes com esclerose lateral amiotrófica foi correlacionado com severidade da doença e pode sugerir menor sobrevida.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Amyotrophic Lateral Sclerosis/mortality , Nocturnal Myoclonus Syndrome/epidemiology , Sleep , Case-Control Studies , Canada/epidemiology , Kaplan-Meier Estimate , Polysomnography , Prevalence , Severity of Illness Index , Statistics, Nonparametric , Symptom Assessment , Sleep Apnea Syndromes/diagnosisABSTRACT
OBJECTIVE: To describe the prevalence and severity of periodic limb movements during sleep in amyotrophic lateral sclerosis patients and to explore this fact as a predictor of severity of the condition with respect to mortality. METHODS: In this case-control study, questionnaire and polysomnographic data were analyzed from 35 amyotrophic lateral sclerosis patients. Controls were matched by age, genre, and body mass index. A Kaplan-Meier curve was used to compare the survival time of patients with periodic limb movements of sleep index below or above 5. RESULTS: The number of amyotrophic lateral sclerosis patients with an index greater than five was higher than controls (19 (53%) versus 4 (11%); p < 0.0001), and the mean index was higher (23.55 ± 40.07 versus 3.28 ± 8.96; p = 0.0009). Earlier mortality was more common in patients with more than five periodic limb movements per hour of sleep than patients with less than five periodic limb movements per hour of sleep (7/19 (37%) versus 1/16 (6%); p = 0.04) in this group of patients that had a mean survival of 33 months. CONCLUSIONS: There were more periodic limb movements of sleep in amyotrophic lateral sclerosis patients than in the control population. The higher number of these movements in amyotrophic lateral sclerosis patients correlates with disease severity and may suggest poor survival.