This leaflet answers common questions about nerve conduction studies and electromyography (EMG). If you would like further information, or have any worries, please do not hesitate to ask the doctor performing your test.

A doctor will explain the studies to you on the day of your appointment and answer any questions you may have.

What is a nerve conduction study/EMG?

These are tests of nerve and muscle function. Nerve conduction studies look at the messages sent by the nerves in the arms and legs. EMG looks at the electrical activity of the muscles. These tests help us understand if any change in feeling or weakness you may be experiencing is caused by a problem affecting the nerves or muscles.

What will happen during the test?

During a nerve conduction study, small electrode stickers are placed on the arms or legs and a harmless electrical impulse is given. You will feel a tapping/tingling sensation which may cause some of the nearby muscles to twitch.

Some patients may need to have an EMG. During an EMG, the activity of the muscles is measured using a fine needle.

The test will be carried out in the neurophysiology department at Royal Free Hospital, located on the first floor behind clinic 2.

Before the test

To prepare for the test, please:

  • Remove all moisturiser, lotion, or oil from the skin.
  • Wear short-sleeved clothes and loose trousers so you can easily expose the arms and legs.
  • Remove watches and wrist jewellery (a wedding ring may be worn).

Please tell us if you are taking any blood thinning medication, such as warfarin. If you have a cardiac pacemaker, you can still have the test but please tell the doctor beforehand.

After the test

The results of your test will be sent to the clinician who requested the test. We may not be able to provide a report on the day of the test as the study needs to be analysed.

Risks and side-effects

These are very safe tests, which usually have minimal or no side effects. EMG may produce a pinprick sensation and can leave a small bruise.