EMG stands for Electromyography and NCS stands for Nerve Conduction Studies. The test has two parts:

  1. An Electromyogram (EMG) measures the electrical activity of muscles at rest and during contraction. Nerves control the muscles in the body by electrical signals (impulses), and these impulses cause the muscles to react in specific ways. Nerve and muscle disorders cause the muscles to react in abnormal ways. During an Electromyography study, a very small pin is inserted in the muscle that helps us evaluate the condition of your muscles.
  2. Nerve Conduction Studies (NCS) are used to measure the health of your nerves. Mild electrical stimulation is administered to the skin directly overlaying the nerve. The response is measured by a second set of electrodes applied to the surface of the skin. This impulse produces a visual signal on a computer monitor and when analyzed it can provide information about the condition of the nerve.

Measuring the electrical activity in muscles and nerves can help find diseases that damage muscle tissue (such as myopathy and muscular dystrophy) or nerves (such as amyotrophic lateral sclerosis or peripheral neuropathies). EMG and Nerve Conduction Studies are often done together to provide us with more complete data.