EMG Test (Nerve Test)

Electromyography (EMG) is a test to see how some of your nerves and muscles are working. Your doctor has recommended this test to help diagnose your problem. The results may help your doctor decide what treatment is best for you.
Why am I having this test?
Your doctor has recommended this test to see if there is a problem with your muscles or nerves. Symptoms of muscle or nerve problems include numbness, tingling, pain, cramping or weakness. The test may help determine what is causing your symptoms and may help your doctor determine what treatment is best for you.
What happens during the test?
There are 2 different tests that are commonly done:
- Nerve Conduction Studies:
This test shows how your nerves are working. A small electric shock is applied to a nerve and the response is recorded on the testing machine. Several nerves are usually tested on each limb.
- Needle EMG
This test shows the function of muscles. Since nerves connect to the muscles it gives more information about nerves too. A very thin needle is put into a muscle and the activity of the muscle is recorded. For most people the discomfort is mild. The needle is only used once for each patient and is thrown away after the test.
How should I prepare for the test?
You can take your usual medications. You can eat and drink normally the day of the test. You can do normal activities before and after the test. Do not use any lotions or oils on your skin. Tell the doctor if you are taking blood thinners such as Coumadin, Plavix, Effient or Ticlid.
How long will the test take?
The test usually takes between 20-60 minutes. This depends on how many limbs are tested.
When will I know the results of the test?
The doctor may discuss the results with you after the test. You should have a plan to see the doctor who sent you for the test to talk about the next step in your care.
Online Resources
AANEM (American Academy of Neuromuscular and Electrodiagnostic Medicine)