What is Nerve Conduction Study (NCS)?

Nerve Conduction Study or NCS is a specialized test to measure the electrical activity in your nerves. Our nerves carry information by the way fo electrical impulses, and the speed and intensity by which they travel can indicate if there are irregularities in your nerve functions or if the nerves are damaged. That is exactly what is measured in NCS, by stimulating short and safe electrical pulses to course through your nerves under supervision. 

When is NCS needed?

NCS is usually prescribed when you experience prolonged pain and discomfort in your muscles that does not subside through any pain remedies or does not follow any visible injury. The symptoms may include:

  • Prolonged cramping
  • Sharp pain in the muscles
  • Dull, referred pain that spread through the affected limb
  • Tingling or needling sensations
  • Muscle weakness

What do NCS diagnose?

  • Neuro-muscular diseases such as Muscle Dystrophy
  • Peripheral Nerve Damage
  • Spinal cord problems
  • Pinched or sprained nerves
  • Auto-immune diseases such as Multiple Sclerosis 


  • Don't use any cream or lotion on your hands, preferably since the last shower. The test requires attaching electrodes to your body and having a layer of lotion on may interfere with the results.
  • Do not forget to inform the doctor if you have a pacemaker or any wearable medical device on you; the test may interfere with their functions and vice versa.
  • Inform your doctor about all the medications you are taking at the moment. They may advise you to skip certain medicines before the test.


You will be told to sit or lie down in a relaxed position. The muscles on which the test is to be performed will then be anointed with a special lotion and electrode patches will be attached to that part. Palms or hands are the most typically tested sites. If you have a pacemaker, the doctor will avoid going too close to your torso. 

A stimulating electrode will pass mild and safe doses of electrical impulse. The other electrodes will record the response of your nerves. It is important that you remain relaxed and do not move too much during the test, as too much muscular activity can interfere with the results. In many cases, an NCS is followed by an Electromyography (EMG) and is usually done in the same session.


Patients may have reservation about being given electrical shocks, but the impulses used for NCS are so mild that usually there is no risk involved. You may feel some discomfort for the duration of the test, but no effects remain once it is over.