Nerve tests, also called electrodiagnostic studies, are used to determine whether the electrical activity of the nerves has been disrupted as a result of problems in the back. The most common is electromyography. Also called an EMG or myogram, electromyography is a procedure that involves inserting needle electrodes through the skin into a muscle. The electrical activity detected by the electrodes is displayed on a piece of equipment called an oscilloscope that resembles a TV screen with wavy lines crossing it. The presence, size and shape of the waves produced on the screen tell your doctor how able your muscles are to respond to nerve stimulation and can assist in the diagnosis of problems involving the nervous system.

Read about the use of electromyography in diagnosing spinal stenosis.