Electromyography (EMG) and Nerve Conduction Studies (NCS)
These tests are used to evaluate numbness, weakness, or pain of the arms or legs. These tests can be used to diagnose carpal tunnel syndrome, pinched nerves in the neck or lower back (radiculopathy), or peripheral neuropathy. These tests are also useful in diagnosing less common problems, such as myopathies or ALS (amyotrophic lateral sclerosis).
In the nerve conduction studies, small sticker electrodes are placed on the hand or foot and the patient receives small electric shocks to see how well the nerves are conducting signals. For the EMG, a thin needle is placed in different muscles to record electrical activity.
Precautions: Nerve conduction studies should not be done in patients with pacemakers, implanted defibrillators or other implanted electrical stimulators. Needle EMG should not be done on patients receiving Warfarin or Heparin products.
Preparation for the Test:
Wear loose-fitting pants that can be rolled above the knee and a short-sleeved shirt that can be rolled up to the shoulder.
Do not use any moisturizing lotion or skin cream on the day of the test as this can affect the results.
You may eat normal meals and take your medications on your regular schedule.