An Electromyogram (EMG) measures the electrical activity of the muscle during contraction and relaxation. EMG testing is useful in identifying problems arising from a pinched nerve in the spine as well as diseases of the muscles themselves.
Nerve conduction (NCV) is often done along with an EMG and measures how fast an impulse is transmitted from one end of a nerve to the other. This test is useful in detecting nerve-related problems such as Carpal Tunnel Syndrome.
Prior to the doctor beginning the test a medical assistant will check the temperature of the extremity you having the test done on. For optimal conduction of nerves, it is important that your extremity not be too cold. If you are on the colder side the medical assistant will provide you with warm water to hold onto or submerge in until you are at ideal temperature.
Once you are ready for the test, the doctor will ask that you lay flat on the exam table, and electrodes will be placed to the surface of your skin. Small, very low, electrical current is used to stimulate the nerve. The electrical currents are repeated in small, short intervals, with varying intensity (never more than you can handle). The doctor will view and record the electrical activity of your muscles on a computer monitor.
During the nerve conduction portion of the exam electrodes are placed at each end of the nerve being examined. The nerve is stimulated with external electricity, like the EMG portion of the exam, the stimulation is very low and generally painless.
Discomfort or pain should not be felt during the test, which typically lasts between 45-60 minutes. If you do experience any pain or discomfort, please inform the doctor performing the test.
Do not use any lotions or creams 24 hours prior to your appointment.
For lower extremity testing, please bring a pair of loose-fitting shorts that you can change into upon your arrival to your test.
For upper extremity testing, please wear or bring a loose-fitting short sleeved shirt to your test.
For facial testing, please do not apply any lotion, cream, or make up to your face and neck area.