Neurophysiology of neuromuscular transmission and its disorders

Abstract

Despite several antibody tests being available for the assessment of disorders of neuromuscular transmission, electrophysiological testing of the neuromuscular junction remains a very important part of clinical practice. The neuromuscular junction is a complex structure and an understanding of its anatomy and physiology can assist in better understanding the value of electrodiagnostic testing. The most common disorders include myasthenia gravis, Lambert-Eaton myasthenic syndrome, and botulism, and are usually readily identified using several electrophysiological techniques including slow (2-3 Hz) and fast (20- to 50-Hz stimulation). Single-fiber needle EMG remains an additional powerful and sensitive test for patients with disorders that are more mild, in whom repetitive stimulation testing is negative or indeterminate. © 2007 Humana Press Inc.