Objective To determine the diagnostic accuracy of the intensity of fasciculation evaluated by muscle ultrasound in the differential diagnosis of amyotrophic lateral sclerosis (ALS). Methods We prospectively recruited patients who had ALS and neuropathy-radiculopathy attending Peking Union Medical College Hospital from 2017 to 2020. Healthy adults from a community were recruited as healthy controls. Muscle strength was assessed using the Medical Research Council (MRC) scale. At the first visit to the hospital, patients were assessed for maximal grade of fasciculations, total fasciculation score, and fasciculation grade in 16 muscle groups of bilateral upper and lower limbs using ultrasonography. The sensitivity and specificity of maximal grade of fasciculations, total fasciculation score, and fasciculation grade for the diagnosis of ALS were assessed by receiver operating characteristic analyses. Results The percentage of limb muscles with a maximal fasciculation grade higher than grade 2 in ALS patients and neuropathy-radiculopathy patients was 84.9% and 9.8%, respectively (χ² = 172.436, P < 0.01). Of the 16 limb muscles detected, the total fasciculation score [median (interquartile range)] was 29 (15, 41) in ALS patients and 3 (0, 8) in neuropathy-radiculopathy patients (Z = 9.642, P < 0.001). Remarkable fasciculations were seen in ALS patients whose muscles with a MRC score ranging from 2 to 4, followed by patients with MRC score 5, and then in those with MRC score 0 and 1. The sensitivity and specificity of total fasciculation score for diagnosis of ALS were 80.6% and 93.4%, respectively (cut-off value 14). In patients with ALS, for muscles with MRC score 4 and 5, the percentage of muscles with fasciculation grades ≥ 3 was 42.3% and 24.1% respectively, while in neuropathy-radiculopathy patients, the percentage for muscles with MRC score 4 and 5 was only 1.7% and 0, respectively. Conclusion A combined analysis of fasciculation intensity and MRC score of the limb muscles may be helpful for differential diagnosis of ALS.
Adult ; Humans ; Amyotrophic Lateral Sclerosis/diagnostic imaging* ; Fasciculation/diagnostic imaging* ; Radiculopathy ; Muscle, Skeletal/diagnostic imaging* ; Ultrasonography/methods*

Isolated respiratory onset amyotrophic lateral sclerosis (ALS) is a rare clinical manifestation and the diagnosis can be challenging. A 72-year-old man presented with dyspnea and hypercapnia that had started 11 months earlier. A phrenic nerve study was conducted and he was diagnosed promptly with ALS with no significant time delay. The phrenic nerve study is a noninvasive and useful tool in the diagnosis of respiratory onset ALS that can be applied easily in an emergency department.
Aged ; Amyotrophic Lateral Sclerosis* ; Diagnosis ; Dyspnea ; Early Diagnosis* ; Emergency Service, Hospital ; Fasciculation ; Humans ; Hypercapnia ; Phrenic Nerve*

Motor neuron diseases (MNDs) refer to a heterogeneous group of progressive neurologic disorders caused by degeneration of motor neurons. The diseases affect either the upper motor neurons, lower motor neurons, or both, and are characterized by weakness, atrophy, fasciculation, spasticity, and respiratory failure. We report a case of a 61-year-old male patient with no past history of cardiovascular or pulmonary disease, who presented with only dyspnea, and no indication of any other symptom such as muscle weakness, atrophy, or bulbar dysfunction. Neuromuscular conduction study, including a study of the phrenic nerve, confirmed the diagnosis of MND. The patient greatly improved giving respiratory assistance at night, using a noninvasive ventilator. This case indicates that MNDs should be considered as differential diagnoses for patients showing acute respiratory failure of unknown causes. This report will aid in the prompt diagnosis and treatment of MNDs.
Atrophy ; Diagnosis ; Diagnosis, Differential ; Dyspnea ; Fasciculation ; Humans ; Lung Diseases ; Male ; Middle Aged ; Motor Neuron Disease* ; Motor Neurons* ; Muscle Spasticity ; Muscle Weakness ; Nervous System Diseases ; Phrenic Nerve ; Respiration, Artificial ; Respiratory Insufficiency* ; Ventilators, Mechanical

BACKGROUND: To achieve a prolonged therapeutic effect in patients with lumbar facet joint syndrome, radiofrequency medial branch neurotomy (RF-MB) is commonly performed. The purpose of this study was to evaluate the prognostic value of paravertebral muscle twitching when performing RF-MB in patients with lumbar facet joint syndrome. METHODS: We collected and analyzed data from 68 patients with confirmed facet joint syndrome. Sensory stimulation was performed at 50 Hz with a 0.5 V cut-off value. Patients were divided into 3 groups according to the twitching of the paravertebral muscle during 2 Hz motor stimulation: ‘Complete’, when twitching was observed at all needles; ‘Partial’, when twitching was present at 1 or 2 needles; and ‘None’, when no twitching was observed. The relationship between the long-term effects of RF-MB and paravertebral muscle twitching was analyzed. RESULTS: The mean effect duration of RF-MB was 4.6, 5.8, and 7.0 months in the None, Partial, and Complete groups, respectively (P = 0.47). Although the mean effect duration of RF-MB did not increase significantly in proportion to the paravertebral muscle twitching, the Complete group had prolonged effect duration (> 6 months) than the None group in subgroup analysis. (P = 0.03). CONCLUSIONS: Paravertebral muscle twitching while performing lumbar RF-MB may be a reliable predictor of long-term efficacy when sensory provocation under 0.5 V is achieved. However, further investigation may be necessary for clarifying its clinical significance.
Ablation Techniques ; Catheter Ablation ; Fasciculation ; Humans ; Low Back Pain ; Needles ; Prognosis ; Zygapophyseal Joint

Amyotrophic lateral sclerosis (ALS), the most common adult onset motor neuron disease, is pathologically characterized by progressive loss of the upper and lower motor neurons. Mutations in the Cu/Zn superoxide dismutase gene (SOD1) account for about 20% of familial ALS cases and a small percentage of sporadic ALS (SALS) cases, and have revealed a validated genotype-phenotype correlation. Herein, we report a p.Gly13Arg mutation in SOD1 exon 1 in a patient with SALS who presented with a rapidly progressive course, predominantly affecting the lower motor neurons. A 48-year-old man presented with progressive weakness and muscle atrophy of the left upper and lower limbs, followed by muscle fasciculation and cramping. The clinical features of the patient were clearly suggestive of ALS, and implied a sporadic form with rapid progression, predominantly affecting the lower motor neurons. Sequencing of the SOD1 gene by PCR revealed a missense mutation of G to C (c.37G>C) in exon 1, and amino acid substitution of glycine by arginine (p.Gly13Arg). This is the first case identifying the p.Gly13Arg mutation of SOD1 in the Korean population, and clinical assessments of this patient revealed a different phenotype compared with other cases.
Adult ; Amino Acid Substitution ; Amyotrophic Lateral Sclerosis ; Arginine ; Exons ; Fasciculation ; Genetic Association Studies ; Glycine ; Humans ; Lower Extremity ; Middle Aged ; Motor Neuron Disease ; Motor Neurons ; Muscle Cramp ; Muscular Atrophy ; Mutation, Missense ; Phenotype ; Polymerase Chain Reaction ; Superoxide Dismutase

BACKGROUND: Succinylcholine commonly produces frequent adverse effects, including muscle fasciculation and myalgia. The current study identified the optimal dose of rocuronium to prevent succinylcholine-induced fasciculation and myalgia and evaluated the influence of rocuronium on the speed of onset produced by succinylcholine. METHODS: This randomized, double-blinded study was conducted in 100 patients randomly allocated into five groups of 20 patients each. Patients were randomized to receive 0.02, 0.03, 0.04, 0.05 and 0.06 mg/kg rocuronium as a precurarizing dose. Neuromuscular monitoring after each precurarizing dose was recorded from the adductor pollicis muscle using acceleromyography with train-of-four stimulation of the ulnar nerve. All patients received succinylcholine 1.5 mg/kg at 2 minutes after the precurarization, and were assessed the incidence and severity of fasciculations, while myalgia was assessed at 24 hours after surgery. RESULTS: The incidence and severity of visible muscle fasciculation was significantly less with increasing the amount of precurarizing dose of rocuronium (P < 0.001). Those of myalgia tend to decrease according to increasing the amount of precurarizing dose of rocuronium, but there was no significance (P = 0.072). The onset time of succinylcholine was significantly longer with increasing the amount of precurarizing dose of rocuronium (P < 0.001). CONCLUSIONS: Precurarization with 0.04 mg/kg rocuronium was the optimal dose considering the reduction in the incidence and severity of fasciculation and myalgia with acceptable onset time, and the safe and effective precurarization.
Fasciculation* ; Humans ; Incidence ; Myalgia* ; Neuromuscular Blockade ; Neuromuscular Monitoring ; Succinylcholine* ; Ulnar Nerve

Flail arm syndrome (FAS), an atypical presentation of amyotrophic lateral sclerosis (ALS), is characterized by progressive, predominantly proximal, weakness of upper limbs, without involvement of the lower limb, bulbar, or respiratory muscles. When encountering a patient who presents with this symptomatic profile, possible diagnoses include upper limb onset ALS (UL-ALS), and FAS. The lack of information regarding FAS may make differential diagnosis between FAS and UL-ALS difficult in clinical settings. The aim of this study was to compare clinical and electromyographic findings from patients diagnosed with FAS with those from patients diagnosed with UL-ALS. To accomplish this, 18 patients with FAS and 56 patients with UL-ALS were examined. Significant differences were observed between the 2 groups pertaining to the rate of fasciculation, patterns of predominantly affected muscles, and the Medical Research Council scale of the weakest muscle. The presence of upper motor neuron signs and lower motor neuron involvement evidenced through electromyography showed no significant between-group differences.
Amyotrophic Lateral Sclerosis* ; Arm* ; Diagnosis ; Diagnosis, Differential ; Electromyography ; Fasciculation ; Humans ; Lower Extremity ; Motor Neuron Disease ; Motor Neurons ; Muscles ; Respiratory Muscles ; Upper Extremity*

BACKGROUND AND PURPOSE: X-linked bulbospinal muscular atrophy (X-BSMA) is characterized by bulbar and spinal muscular weakness and fasciculations. Although X-BSMA is a motor neuronopathy, there are several reports of myasthenic symptoms or decremental responses to repetitive nerve stimulation (RNS). We report the results of applying the RNS test to 15 patients among 41 with genetically confirmed X-BSMA; these 15 patients complained of fatigue, ease of becoming tired, or early muscular exhaustion. METHODS: The 3-Hz RNS test was performed on the trapezius, nasalis, orbicularis oculi, flexor carpi ulnaris, and abductor digiti quinti muscles. A decrement greater than 10% was considered abnormal. Additionally, a pharmacologic response to neostigmine was identified in three patients. RESULTS: A significant decrement was observed in 67% of patients, and was most common in the trapezius muscle (nine cases). The decrement of the trapezius muscle response ranged from 15.9% to 36.9%. The decrement was inversely correlated with the amplitude of compound muscle action potentials at rest. Neostigmine injection markedly improved the decrement in three patients, who showed noticeable decremental responses to 3-Hz RNS. CONCLUSIONS: This study shows that myasthenic symptoms and abnormal decremental responses to low-rate RNS are common in X-BSMA.
Action Potentials ; Bulbo-Spinal Atrophy, X-Linked ; Fasciculation ; Fatigue ; Humans ; Motor Neuron Disease ; Muscle Weakness ; Muscles ; Muscular Atrophy ; Myasthenia Gravis ; Neostigmine ; Neuromuscular Junction

BACKGROUND: An experimental study was done to compare the efficacy of inside-out vein graft versus autogenous nerve graft as nerve conduit in promoting axonal regeneration in a rat model.

METHODS: The study used 16 Spraque-Dawley rats randomly divided into two groups: the inside-out vein graft group and control group (autognous nerve graft). The outcomes measured were histomorphology (axon number and diameter), muscle twitch response (amplitude) and the walking track analysis at 2, 4 6 and 8 weeks.

RESULTS: The inverted vein graft and control groups showed similar axon diameter (P=0.76), and axon number (P=0.85), weeks and similar muscle twitch responses (P=0.87) after eight weeks. The walking track analysis showed no significant difference between the two groups at eight weeks.

CONCLUSION: The study showed that the inside-out vein graft group had similar motor recovery as compared to control group based on the muscle twitch analysis and walking track analysis in a rat model.In terms of histomorphometric analysis, the two groups were similar in terms of axon diameter and axon count.

BACKGROUND AND PURPOSE: While the etiology and clinical features of "EMG disease" - which is characterized by diffusely increased insertional activity on needle electromyography (EMG) in the absence of neuromuscular disease - are not well known, some authorities believe it may be a form of myotonia congenita (MC). The aims of this study were to determine the clinical features of EMG disease and its relationship with CLCN1 mutations in patients. METHODS: The detailed clinical and electrophysiological features of EMG disease were evaluated in six patients. All 23 coding exons and exon-intron boundaries in CLCN1 gene were analyzed by direct sequencing to detect nucleotide changes. RESULTS: The common clinical symptoms of EMG disease were chronic muscle stiffness or generalized myalgia, which were aggravated in a cold environment. Four patients complained of action myotonia several times a year. Short trains of provoked positive sharp waves were documented on needle EMG, but myotonic discharges, fibrillation potentials, and fasciculations were not. Increased insertional activity was identified at the asymptomatic muscles studied. One novel heterozygous mutation was identified in one patient following genetic testing for CLCN1 mutations (c.1679T>C, p.Met560Thr). CONCLUSIONS: The clinical features of EMG disease might be quite similar to those of MC, but CLCN1 mutation was found in only one subject. It is thus difficult to accept that EMG disease lies within the phenotypic spectrum of MC. Additional testing is needed to verify the pathogenetic cause of the diffusely increased insertional activity associated with this condition.
Chloride Channels ; Clinical Coding ; Cold Temperature ; Electromyography ; Exons ; Fasciculation ; Genetic Testing ; Humans ; Muscles ; Myotonia ; Myotonia Congenita ; Needles ; Neuromuscular Diseases