Nerve conduction studies

Nerve conduction studies (NCS) assess the electrical conduction of impulses travelling along the nerves. To obtain these measurements, a speciali recording electrode is placed on to the skin (usually on your hand, arm or leg) and then another electrode is used to stimulate the skin. The 'stimulator' produces small electrical pulses which feel like a sharp tapping sensation. This process is repeated for a number of different nerves. Although some people find it uncomfortable, it cannot do you any harm and there are no side effects. Usually the nerves of the arms and legs are examined in this way.

Nerve conduction studies measure how quickly a nerve impulse travels along a nerve. If the nerve is trapped, damaged or diseased then these signals will be altered.

Patients should inform the clinical neurophysiology department if they have a cardiac pacemaker or an implanted cardiac defibrillator. 

The consultation and testing duration varies according to the patient’s problem and the extent of the testing required. Typically the appointment will be between 30 minutes and one hour.

Preparing for NCS

In preparation, patients are advised to keep their hands and feet warm, as cold limbs can affect the results. In addition patients are asked to avoid using any kind of moisturiser/creams/lotions on the arms or legs on the day of the tests, as this can interfere with the recordings. Patients should wear loose clothing and minimal jewellery, which may need to be removed.