Nerve Conduction Study
by Cynthia M. Johnson, MA
A nerve conduction study (NCS) measures the speed and strength of electrical activity in a nerve. The test can gather details about the structure and function of muscles and nerves.
Reasons for Test
A NCS is most often done to:
There are no major problems from this test.
What to Expect
Prior to Test
The care team may meet with you to talk about:
Description of Test
Your skin will be cleaned. Electrodes will be taped to the skin along the nerves that are being studied. One electrode will stimulate the nerve with a mild electrical impulse. It will cause the nerves to activate. The electrodes will measure the current that travels down the nerve pathway. The current will be slower and weaker if the nerve is damaged. An electrical impulse will be used at different places to find the site of any damage.
Nerve conduction studies are often done along with electromyography (EMG).
How Long Will It Take?
About 30 to 90 minutes
Will It Hurt?
The test areas may be sore. This will go away in an hour or 2.
The doctor will study the details from the test. A report should be ready within a few days.
Call Your Doctor
Call your doctor if you have any questions or concerns after the test.
If you think you have an emergency, call for medical help right away.
American Chronic Pain Association
National Institute of Neurological Disorders and Stroke
Canadian Neurological Sciences Federation
Chronic Pain Association of Canada
Electrodiagnostic testing. American Academy of Orthopaedic Surgeons website. Available at:
...(Click grey area to select URL)
Accessed October 1, 2020.
Nerve conduction studies. Johns Hopkins website. Available at: https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/nerve-conduction-studies. Accessed October 1, 2020.
Peripheral neuropathy. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/peripheral-neuropathy. Accessed October 1, 2020.
Spinal diagnostics: nerve conduction studies. Cedars Sinai website. Available at: https://www.cedars-sinai.org/health-library/diseases-and-conditions/s/spinal-diagnostics-nerve-conduction-studies.html. Accessed October 1, 2020.
Last reviewed September 2020 by EBSCO Medical Review Board Rimas Lukas, MD
Last Updated: 5/21/2021
EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.
This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.
To send comments or feedback to our Editorial Team regarding the content please email us at email@example.com. Our Health Library Support team will respond to your email request within 2 business days.