An EMG analyzes the electrical activity in your muscles. It is used to learn more about the functioning of nerves in the arms and legs to help determine pain generator from your spine (radiculopathy or pinched nerve) or peripheral nervous system (carpal tunnel syndrome, neuropathy, myopathy, etc).
During an EMG, small, thin pins are placed in the muscle to record the electrical activity. You may feel some discomfort. The doctor will ask you to relax the muscle and to tense it slightly. You may experience some soreness and bruising, but this will disappear in a few days. There are no long-term side effects.
Nerve Conduction Studies
NCS are done to determine if a nerve is functioning normally. The nerve is stimulated with an electric current. As the current travels down the nerve pathway, the electrodes placed along the way capture the signal. In healthy nerves, electrical signals can travel at up to 220 kilometers per hour. If the nerve is damaged, the signal will be slower and weaker. The procedure is not painful and most people are comfortable during the testing procedure. The shock is similar to one received when you touch a doorknob after walking across carpeting.
Electrodiagnostic testing also can be used to determine the extent of injury to a nerve after an accident or determine presence of diabetic neuropathy or other types of neuropathies and peripheral nerve problems.