Electromyography (EMG) is a test of nerve and muscle function. Your doctor may order an EMG if you experience numbness, weakness, or pain that could be related to a nerve or muscle disorder.
The test is divided into two parts:
- The first part, nerve conduction studies, is usually performed by a neurology physician, fellow, or technician. Small metal discs (electrodes) are attached to your skin over a muscle or nerve, usually in the hand or foot. Another electrode is placed on your skin over a nearby nerve, usually on the arm or leg. A small electrical current is applied to stimulate the nerve, and the response is recorded.
- The second part, needle EMG, is performed by your doctor. A small needle is inserted into your muscles to measure their activity. The number of nerves and muscles tested depends on your diagnosis and the request of the referring physician, but a typical test involves stimulating four to five nerves and measuring five to six muscles per limb. In general, nerve conduction studies take about 15-20 minutes per limb, and the EMG takes about 5-10 minutes per limb. A test of your right arm and leg, for example, might take about an hour.
Many patients are nervous when they come for an EMG because they hear that the test is very painful. Although there is some discomfort, we do our very best to minimize it and make you as comfortable as possible. In our experience, most patients say it isn’t as bad as they had expected.
Preparing for nerve conduction studies and electromyography
Please take any medications you normally would. However, tell your doctor if you are taking any blood thinners, such as warfarin (Coumadin) or aspirin, or if you have a bleeding disorder. Your doctor may choose not to perform the needle part of the examination if you are taking a blood thinner or have bleeding problems. Finally, do not use lotion on your arms or legs, as it prevents the electrodes from sticking properly.
Talk to your physician about whether an EMG is appropriate for you. For referral appointments, please call neurologists Jessica Robinson-Papp, MD, at 212-241-8390, David M. Simpson, MD, at 212-241-8748, or Mark A. Sivak, MD, at 212-241-7076. EMG is performed in the clinical neurophysiology area, located in the Annenberg Building, second floor (area 218).
Jessica Robinson-Papp, MD
David M. Simpson, MD
Mark A. Sivak, MD
Rajeev Motiwala, MD