The electromyography (EMG) examination is a test of nerve and muscle function. The EMG exam may include nerve conduction studies and the EMG needle exam.
Nerve conduction studies are performed by placing disks on the skin over nerves and muscles and recording responses to electrical stimulation of the nerves. The nerves are stimulated with mild electrical impulses that are felt as slight shocks, much like the sensation experienced when you touch a door knob after walking across a wool rug in cold weather.
The EMG needle exam involves direct recording of muscle activity at rest and during movement, and is done by inserting a small needle into various muscles. A pinprick sensation is experienced when the needle is inserted and sometimes a mild, dull ache is noted while the needle is in place. The EMG exam is safe, well-tolerated, and involves only minor discomfort.