Also known as an electromyogram or EMG, a nerve conduction study measures electrical impulses sent by muscles in a resting mode and during action or contraction modes. The study stimulates nerves in the muscles. It's used as a diagnostic tool to determine the function or blockage of nerves or neural pathways.
You'll be asked to lie down on a table while electrodes are attached to your skin with paste or tape. The electrodes are small metal disks usually inserted into white self-adhesive sticker-like coverings.
A wire from the electrode is attached to a small machine that a technician uses to record and measure reaction of your muscle or muscles to small jolts of electrical stimulation. Several pulses are generally delivered at a time. You may feel the muscle twitch, or feel a slight tingling or burning sensation while the electrical impulse travels through the muscle.
Low voltage electrical impulses are used, and some people experience slight discomfort, but usually not severe. The process measures the time it takes for your muscle to contract following the electrical stimulation. This time frame is called conduction velocity.
Depending on the area being tested, a nerve conduction study test may take as few as 15 minutes once the electrodes are attached. The process may take longer if more than one area of the body is being tested.