EMG/NCS

EDX Tests

Nerve conduction studies

Nerve conduction studies show how well the body’s electrical  signals are traveling to a nerve. This is done by applying small electrical shocks to the nerve and recording how the nerve works. These shocks cause a quick, mild, tingling feeling. The doctor may test several nerves during an exam.

​

Needle EMG

For this test, a small, thin needle is inserted into several muscles to see if there is any abnormal electrical activity. The needle is used once for each patient and is thrown away after the test. There may be some pain during this part of the examination. However, the doctor can use a spray to help numb the skin. The doctor will test only the muscles necessary to decide what is wrong. During the EMG test, the doctor will be able to hear and see how your muscles and nerves are working by the electrical signals made by your muscles. The doctor then uses his medical knowledge to figure out what could be causing your problem.

 

Why am I being sent to the EMG Lab for tests?

You are being sent to the EMG lab because you have numbness, tingling, pain, weakness, or muscle cramping. Some of the tests that the EMG doctor may use to diagnose your symptoms are nerve conduction studies, needle EMGs, and evoked potentials. The EMG doctor will examine you to decide which tests to do.

​

How long will these tests take?

The tests usually take 20 to 90 minutes. You can do any of your normal activities, like eating, driving, and exercising, before the tests. There are no lasting side effects. You also can do your normal activities after the tests.

 

How should I prepare for the tests?

Tell the EMG doctor if you are taking aspirin, blood thinners (like Coumadin®), have a pacemaker, or have hemophilia. Take a bath or shower to remove oil from your skin. Do not use body lotion on the day of the test. If you have myasthenia gravis, ask your EMG doctor if you should take any medications before the test.