Factors influencing the result of an electroneurographic examination

Purpose
Author reviews up-to-date publications and provides comprehensive information on the most common pitfalls of electrodiagnostic tests. regarding commonly en-countered pitfalls in electrodiagnostic studies. The article presents also influence of devices settings, proper conditions of nerve conduction studies and factors that may affect their results.

Views
Electrodiagnostic tests, including electroneurographic (ENG) and electromyographic (EMG) examinations, are the gold standard in the evaluation of the function of peripheral nerves, neuromuscular junction and muscles. The main objective of these tests is to determine the type and location of the damage, but also to determine the characteristics of the various disorders associated with the peripheral nervous system. However, these tests should be considered as an extension and supplement of the patient’s medical history, physical examination, results of other tests and should be always interpreted with the whole clinical picture. Many factors, such as biological, physical, resulting from the instrumentation used and their settings, and technical reasons may affect the result of electrodiagnostic tests or their incorrect interpretation. This may have serious consequences and lead to diagnostic errors.

Conclusions
hysicians should be aware of the electrodiagnostic pitfalls that may lead to erroneous conclusions about the nature of the abnormalities underlying peripheral nerve and muscle disorders. An incorrectly performed examination or its interpretation may affect further treatment or prevent the development of an accurate final diagnosis. In some cases, this may lead to delayed treatment introduction and worse patients outcome.