Neurophysiology simplified for imagers

Electrodiagnostic studies are powerful diagnostic tools that complement the clinical evaluation of patients with neuromuscular disease. However, their proper interpretation requires a hypothesis-driven approach that depends on clinical information and physical examination findings. In principle, Bayesian methods of reasoning determine both the plan of examination and interpretation of results. Thus neuromuscular disease training with an understanding of peripheral nervous system anatomy, nerve and muscle physiology, pathophysiology, pathology, management, and prognosis are as important as technical training for performance of the test. In this article, geared toward imagers, we review the basic principles of electrodiagnostic studies, typical measurements, and their interpretation both in normal and common disease states.