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Overview of nerve conduction studies

Steven H Horowitz, MD
Section Editor
Jeremy M Shefner, MD, PhD
Deputy Editor
John F Dashe, MD, PhD


The unique natural electrical properties of peripheral nerves can be evaluated in health and disease with externally applied stimuli and analysis of the consequent neurophysiologic responses. Nerve conduction study (NCS) techniques permit stimulation and recording of electrical activity from individual peripheral nerves with sufficient accuracy, reproducibility, and standardization to determine normal values, characterize abnormal findings, and correlate neurophysiologic-pathologic features.

These clinical studies are used to:

Diagnose focal and generalized disorders of peripheral nerves

Aid in the differentiation of primary nerve and muscle disorders (although NCS itself evaluates nerve and not muscle)

Classify peripheral nerve conduction abnormalities due to axonal degeneration, demyelination, and conduction block

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Literature review current through: Nov 2017. | This topic last updated: Jan 24, 2017.
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