• Annals of Clinical Neurophysiology
• /
• v.8 no.1
• /
• pp.88-90
• /
• 2006

Pneumothorax after needle electromyography is a rare complication, which usually associated with examination of diaphragmatic and intercostal muscles. However, by the literatures, it can also occur with supraspinatus, serratus anterior and paraspinal muscles. We experienced a case of pneumothorax after cervical paraspinal muscle needle electromyography. From the anatomical vulnerability of pneumothorax during needle insertion, we emphasized the importance of avoiding this complication.

• Annals of Clinical Neurophysiology
• /
• v.10 no.1
• /
• pp.62-65
• /
• 2008

We report a patient with amyotrophic lateral sclerosis (ALS) who developed a pneumothorax after needle electromyography (EMG), probably of the intercostal muscles. Needle EMG on intercostal muscles has a high risk of pneumothorax, not only because electromyographers are unfamiliar to its technique, but also due to its close anatomical location to the pleural cavity. In our patient, advanced intercostal muscle atrophy due to disease process would have increased the risk further.

• Annals of Clinical Neurophysiology
• /
• v.21 no.1
• /
• pp.7-15
• /
• 2019

Clinical evaluations, nerve conduction studies, and electromyography play major complementary roles in electrophysiologic diagnoses. Electromyography can be used to assess pathologic changes and localize lesions occurring in locations ranging from motor units to anterior-horn cells. Successfully performing electromyography requires knowledge of the anatomy, physiology, and pathology of the peripheral nervous system as well as sufficient skill and interpretation ability. Electromyography techniques include acquiring data from visual/auditory signals and performing needle positioning, semiquantitation, and interpretation. Here we introduce the basic concepts of electromyography to guide clinicians in performing electromyography appropriately.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.10 no.1
• /
• pp.30-36
• /
• 1999

Background and Objectives : Laryngeal Evoked Electromyography(EEMG) is a objective, quantitative technique to determine innervation status of larynx. The possible applications of this technique are to confirm the etiology of impaired vocal fold motion and monitor perioperative vagus nerve trauma. The purpose of this study is to develop a novel method for determining the amount of reinnervation of recurrent laryngeal nerve with accurate, inexpensive, and minimally invasive technique in human. Materials and Methods : Laryngeal EEMG was performed for 16 adults with intact vocal folds motion and 2 patients diagnosed as unilateral vocal fold paralysis. for the purpose of searching what is the optimal and noninvasive technique for laryngeal EEMG, we used 2 types of stimulation configurations(transcutaneous vs percutaneous) and 2 types of recording configurations(intramuscular vs. surface). Results and Conclusions : Percutaneous needle stimulation and surface recording of laryngeal EEMG was reliable and comparable to standard needle stimulation and invasive intramuscular needle recording. But the laryngeal EEMG by the surface recording and transcutaneous surface stimulation was not reliable and repeatable. Therefore we recommended that laryngeal EEMG by surface recording and percutaneous needle stimulation would be minimally invasive, reliable technique to know the status of reinnervation in e patients with vocal fold paralysis.

• Annals of Clinical Neurophysiology
• /
• v.20 no.2
• /
• pp.66-70
• /
• 2018

Electrodiagnostic studies such as nerve conduction studies (NCS) and needle electromyography (EMG) provide important and complementary information for evaluating patients with suspected neuromuscular disorders. NCS and needle EMG are reasonably safe diagnostic investigations and are generally associated with only mild transient discomfort when performed by experienced physicians. However, there is the risk of complications in some patients, because NCS involve the administration of electric current and EMG involves inserting a needle percutaneously into muscle tissue. This article reviews the potential risks of NCS and needle EMG.

• Annals of Clinical Neurophysiology
• /
• v.8 no.2
• /
• pp.125-134
• /
• 2006

Among the various physiological factors that affect nerve conduction velocity (NCV), temperature is the most important. Because the influence of temperature is the most important source of error. It is known from animal experiments that conduction is eventually completely blocked at low temperatures, the myelinated A fibers being the first affected and the thin fibers of group C the last. Many studies showed that the NCV decreases linearly with lowering temperature within the physiological range. The distal motor latency increased by $0.2msec/^{\circ}C$ drop in temperature between $25^{\circ}C$and $35^{\circ}C$ in the median, ulnar and peroneal nerves. The temperature affect the neuromuscular transmission; The miniature endplate potential (MEPP) and endplate potential (EPP) are increase with increasing temperature. In myasthenia gravis, the reduction in the decremental response is observed following cooling. The lowering temperature make increase the amplitude of sensory compound action potential; make enlarge the surface area of compound muscle action potential with very little increase in amplitude; make diminish the fibrillation potential and increase the myotonia in needle electromyography (EMG). Because of these findings mentioned above, the skin temperature should be routinely monitored and controlled during nerve conduction tests and needle EMG and should be taken into account when interpreting the findings.

• Annals of Clinical Neurophysiology
• /
• v.24 no.2
• /
• pp.73-78
• /
• 2022

Some cases of myasthenia gravis (MG) with abnormal spontaneous activity (ASA) in needle electromyography (EMG) have been reported, but the associated clinical characteristics remain to be fully elucidated. We report the case of a 36-year-old male with MG in whom ASA was observed. This study highlights that ASA may appear in needle EMG in patients with severe MG who predominantly have bulbar and/or respiratory involvement. Care is needed because this often accompanies myopathic features and can be misdiagnosed as myopathy.

• Annals of Clinical Neurophysiology
• /
• v.7 no.2
• /
• pp.124-126
• /
• 2005

The effect of serratus anterior dysfunction is seen in the scapular winging. We report 2 cases with winging scapula clinically but do not reveal denervation potentials in needle electromyography. Surface myoelectric measurements of median frequency and root mean square values show difference in fatigability and amplitude in affected side.

• Annals of Clinical Neurophysiology
• /
• v.6 no.2
• /
• pp.85-91
• /
• 2004

Background: Needle electromyography (EMG) and motor evoked potential (MEP) of the genioglossus (tongue) are difficult to perform in evaluations of the craniobulbar region in amyotrophic lateral sclerosis (ALS). Therefore, we investigated the yields of needle EMG and MEP recorded from the upper trapezius, since it receives innervation from the lower medulla and upper cervical cord. Methods: Needle EMG and MEP of the upper trapezius were obtained in 17 consecutive ALS patients. The needle EMG parameters recorded included abnormal spontaneous activity and motor unit action potential (MUAP) morphology. An upper motor neuron (UMN) lesion was presumed when either response to cortical stimulation was absent, or the central conduction time was delayed (>mean+2SD). Results: Of the five patients with bulbar-onset ALS, four had abnormalities in the upper trapezius and four in the tongue by needle EMG. In contrast, of the 12 patients with limb-onset ALS, 11 had abnormalities in the upper trapezius, and only five in the tongue. When MEP was performed, it was found that three of the five patients with bulbar symptoms and three of the six patients with isolated limb involvement had abnormal MEP findings. Conclusions: Electrophysiological studies of the upper trapezius are more sensitive those of the tongue in patients without bulbar symptoms. Thus, needle EMG and MEP of the upper trapezius are alternative tools for assessing bulbar and rostral neuraxial involvement in the diagnosis of ALS.

• International journal of advanced smart convergence
• /
• v.12 no.3
• /
• pp.211-220
• /
• 2023

Surface electromyography (sEMG) is a noninvasive method used to capture electrically muscle activity, which can be easily measured even during exercise. The basic unit of muscle activity is the motor unit, and because an sEMG signal is a superposition of motor unit action potentials, analysis of muscle activity using sEMG should ideally be done from the perspective of motor unit activity. However, conventional techniques can only evaluate sEMG signals based on abstract signal features, such as root-mean-square (RMS) and mean-power-frequency (MPF), and cannot detect individual motor unit activities from an sEMG signal. On the other hand, needle EMG can only capture the activity of a few local motor units, making it extremely difficult to grasp the activity of the entire muscle. Therefore, in this study, a method to visualize the activities of motor units in a single-channel sEMG signal by relocating wavelet coefficients obtained by redundant discrete wavelet analysis is proposed. The information obtained through this method resides in between the information obtained through needle EMG and the information obtained through sEMG using conventional techniques.