Electrodiagnostics are procedures that, in the setting of low back pain, are primarily used to confirm whether a person has lumbar radiculopathy. The procedures include electromyography (EMG), nerve conduction studies (NCS), and evoked potential (EP) studies. EMG assesses the electrical activity in a muscle and can detect if muscle weakness results from a problem with the nerves that control the muscles. Very fine needles are inserted in muscles to measure electrical activity transmitted from the brain or spinal cord to a particular area of the body. NCSs are often performed along with EMG to exclude conditions that can mimic radiculopathy. In NCSs, two sets of electrodes are placed on the skin over the muscles. The first set provides a mild shock to stimulate the nerve that runs to a particular muscle. The second set records the nerve’s electrical signals, and from this information nerve damage that slows conduction of the nerve signal can be detected. EP tests also involve two sets of electrodes—one set to stimulate a sensory nerve, and the other placed on the scalp to record the speed of nerve signal transmissions to the brain. 