Needle electromyography (EMG)

Needle electromyography (EMG) is a neurophysiological examination that analyses the electrical activity of muscles using a fine needle electrode inserted into the muscle. This examination makes it possible to assess the integrity of the motor unit, that is, the whole formed by the motor neuron, its axon and the muscle fibres it innervates. Needle EMG successively explores the activity of the muscle at rest (looking for abnormal spontaneous activity such as fibrillations, fasciculations or myotonic discharges), then during a voluntary contraction effort (analysis of the motor unit potentials: morphology, duration, amplitude, recruitment). These parameters make it possible to distinguish a neurogenic condition (nerve disease) from a myogenic condition (muscle disease). This examination is fundamental in the diagnosis of peripheral neuropathies, radiculopathies (sciatica, cruralgia), motor neuron diseases (amyotrophic lateral sclerosis), myopathies and myositides. It provides information complementary to nerve conduction studies and makes it possible to specify the site, severity and duration of the condition. At the Clinique Pasteur in Tunis, the EMG is performed by experienced neurophysiologists using latest-generation electromyography equipment, allowing a fine and precise analysis of the motor unit potentials.