ELECTRONEUROGRAPHY / ELECTROMYOGRAPHY
Electromyography (EMG) and electroneurography (ENG) are neurophysiological methods used to study, from a functional point of view, the peripheral nervous system, allowing to diagnose pathologies of nerve roots, nerve plexuses, peripheral nerves, muscles, plaque neuromuscular. ENG and EMG are performed in succession and are complementary for the purpose of diagnosis: for these reasons, the term electromyography often also refers to electroneurography.
Sensitivity alterations such as: hypoesthesia (reduced tactile sensation), anesthesia (eg "falling asleep"), paraesthesia (eg "tingling"), Strength deficiency affecting individual muscles or muscle groups interpreted by the doctor as peripheral volume of one or more muscles. of the disc, arthrosis with osteophytosis, engagement in the conjugation foramina, etc.).
Do not apply creams or oils to the skin, possibly for 1-2 days since, by running the conduction speeds, these create a barrier to the passage of the electrical stimulus that must reach the nerve. Bring previous tests with you: other previous electromyographic studies, nerve ultrasounds and radiological examinations of the spine (e.g. X-ray, CT and MRI of the cervical, dorsal, lumbo-sacral spine) Warn the examiner if you have a pacemaker or if you take oral anticoagulants (eg Coumadin, Sintrom, Pradaxa, Eliquis, Xarelto) Warn the examiner if serological positivity is known for viral hepatitis (HBV, HCV) and other blood-borne infectious diseases (eg HIV)
The duration of an electromyographic study can be very variable. If the patient is already well framed from the point of view of the clinical history and the objective neurological examination, for which the diagnostic question is well formulated, the study can be performed in a more targeted way and therefore, in general, last less. For this reason, it is often useful for the electromyographic study to be preceded by a neurological evaluation. When it is necessary to perform the evaluation in several districts (e.g. all four limbs rather than just one) and when it is necessary to perform both conduction speeds and needle electromyography, the times are lengthened and can even reach a Now. The cases in which the study lasts less are those in which it is necessary, for example, to study a single limb with only conduction speeds, for example a unilateral carpal tunnel syndrome in the initial stage or in any case not complicated. In this case the study could last as little as 15 minutes. However, it should be kept in mind that there are many variables that can interfere during the evaluation, such as the degree of cooperation of the patient, the degree of impedance of the skin (resistance to the passage of electrical signals), any electromagnetic interference from the surrounding environment.