Electromyography (EMG)

  • 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 NCSs, and needle EMGs.
  • How long will these tests take?
    The tests usually take 20 to 60 minutes, and usually takes about 30 minutes per limb. 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.  Keep your skin warm as a low skin temperature may negatively affect the results.When will I know the test results?The EMG doctor will discuss your test results with you or send them to your regular doctor. After the exam, check with the doctor who sent you to the lab for the next step in your care.
  • Needle EMG
    For this part of the test, a small, thin needle is put in several muscles to see if there are any problems. It is used once for each patient and is thrown away after the test. There may be a small amount of pain during this part of the examination. The doctor tests 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.
  • Nerve conduction studies
    Nerve conduction studies (NCSs) 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.