Electromyogram (EMG)
An electromyogram is a test used to record the electrical activity of muscles. The EMG can detect abnormal muscle electrical activity in many diseases and conditions, including muscular dystrophy, inflammation of muscles, pinched nerves, peripheral nerve damage, disc herniation, and others. Surface EMG (SEMG) involves placing the electrodes on (not into) the skin overlying the muscle to detect the electrical activity of the muscle.