Electromyography, or EMG, is a diagnostic procedure to assess the health of muscles and nerve cells that control the muscle (motor neurons).
Since motor neurons transmit electrical signals that cause the muscles to contract, the EMG utilizes electrodes to translate these signals into graphs, sounds, and numerical values to be interpreted by skilled specialists.
Another aspect of EMG involves needle electrodes, where a needle is inserted into a given muscle to record activity. From there, we record the spikes in electrical currents that occur during voluntary contractions and nerve stimulation, subsequently interpreting and reporting our findings to the patient. Normal, healthy muscle function should not produce activity when the muscle is at rest.
There is also an aspect of EMG, called “Nerve Conduction Study”, which uses electrodes taped to the skin (surface electrodes) to measure the speed and strength of the electrical signals.