Electromyogram

Conventional electromyography is performed by inserting a disposable concentric bipolar needle (steel wire exposed at the tip that functions as an anode, covered by cannula that functions as a cathode) that is inserted into the muscle through the skin and assesses the electrical activity with the muscle at rest, slight contraction and maximum effort. It covers a radius of 1-2.5 mm and allows, as an isolated technique or in combination with neurography, to differentiate neurogenic or myopathic muscle lesions, radiculopathies vs. plexopathies, characterization of polyneuropathies, multineuritis, detection and lesional localization of mononeuropathies, among others.

Isolated fiber electromyography is performed with a sterile needle with a multiple head that covers a radius of less than 300 microns, a complex engineering structure that serves to detect potentials of two muscle fibers belonging to the same motor unit, assessing the “jitter” or differential variation between the activation of one fiber with respect to the other.