What happens during an EMG test and nerve conduction study?
For an EMG test:
You will sit or lie down on a table or bed.
Your provider will clean the skin over the muscle being tested.
Your provider will place a needle electrode into the muscle. You may have slight pain or discomfort when the electrode is inserted.
The machine will record the muscle activity while your muscle is at rest.
Then you will be asked to tighten (contract) the muscle slowly and steadily.
The electrode may be moved to record activity in different muscles.
The electrical activity is recorded and shown on a video screen. The activity is displayed as wavy and spiky lines. The activity may also be recorded and sent to an audio speaker. You may hear popping sounds when you contract your muscle.
For a nerve conduction study:
You will sit or lie down on a table or bed.
Your provider will attach one or more electrodes to a certain nerve or nerves using tape or a paste. The electrodes, called stimulating electrodes, deliver a mild electrical pulse.
Your provider will attach different types of electrodes to the muscle or muscles controlled by those nerves. These electrodes will record the responses to the electrical stimulation from the nerve.
Your provider will send a small pulse of electricity through the stimulating electrodes to stimulate the nerve to send a signal to the muscle.
This may cause a mild tingling feeling.
Your provider will record the time it takes for your muscle to respond to the nerve signal.
The speed of the response is called the conduction velocity.
If you are having both tests, the nerve conduction study will be done first.
