Definition

A nerve conduction study (NCS) is an electrodiagnostic test that measures the speed and degree of electrical activity in a nerve to determine if it is functioning normally. It can gather information about the structural integrity and function of both muscle and nerve.

Electrodiagnostic tests are used to look for problems with nerves and muscles. Nerve conduction studies are often performed along with electromyograms, which are another type of test that analyze the electrical activity in your muscles.

Electromyogram of Shoulder—Used in Conjunction with Nerve Conduction Study

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Parts of the Body Involved

• Skin
• Muscles, usually in the arms or legs
• Nerves ( sensory, motor, and mixed nerves)

Reasons for Procedure

Nerve conduction studies can be performed for a variety of reasons, including:

• Radiculopathy (pain that radiates from the neck or back, to localize site of compression)
• Nerve damage from herniated discs
• Peripheral neuropathy (damage to the longest nerves)
• Focal neuropathy (damage to a single nerve; includes carpal tunnel syndrome)
• Myopathy (muscle disease)
• Diseases of neuromuscular junction (Myasthenia gravis)
• Symptoms indicative of nerve damage, including numbness, weakness, or tingling
• The status of repair and recovery from injury can be assessed
• Differentiation between acute and chronic processes
• Differentiation between acquired and inherited processes
• Differentiation between focal or a diffuse disease process (mononeuropathy or polyneuropathy)
• Assist in narrowing down a differential diagnosis
• Provides prognostic information on the type and extent of injury

Risk Factors for Complications During the Procedure

There are no known complications associated with nerve conduction studies.

What to Expect

Outcome

Once the test is complete, you will be able to resume your daily activities.

Call Your Doctor If Any of the Following Occurs

There are no reported complications after this test.