Nerve Conduction Study (NCS) And Electromyography (EMG)
What is NCS and EMG?
Nerve Conduction Study (NSC) is a diagnostic test that allows doctors to see how well electrical signals are traveling along the nerves. This is done by applying small electrical shocks to the nerve and recording how the nerve responds.
Electromyography (EMG) uses a small, thin needle that is inserted in the muscle to check the activity of the muscle.
When is NCS / EMG used?
The test may be helpful if you have symptoms such as numbness, tingling, weakness, cramping, pain or other loss of function.. It can help doctors to find the cause of these symptoms or to diagnose a range of disorders, conditions, and injuries that might be affecting how your nerves and muscles are functioning.
Certain areas of the upper or lower extremities will be cleaned of any dirt and oils that may be on the surface of the skin to ensure the best results. Then, stick electrodes are placed over specific sites on the skin and small electrical impulses are then applied to record nerve function. The impulse is part of the test and is harmless.
The second part of the test, EMG, involves a tiny pin electrode to measure electrical activity in the muscle.
Are there any side effects following an EMG?
There are no lasting side effects from an EMG, but the testing itself can sometimes be uncomfortable. The NCS involves small electrical shocks to the nerve which may cause a quick tingling or pricking feeling along with an involuntary twitch of the arm or leg. The EMG uses a thin needle inserted into several muscles. These needles are disposable and a new one is used for each patient. Like any needle, some discomfort may be felt. Following the test, you may have slight discomfort in the muscles for a few days and there may be some slight bruising where the needle entered the skin.
How should I prepare for an EMG?
On the day of the test, take a bath or shower but do not apply lotions or oils to the skin. This is to ensure the adhesiveness of the electrodes and to record proper responses. Loose fitting clothing is recommended to allow for better access to your extremities.
Who performs the EMG?
A highly qualified doctor will do all needle EMG testing. A technologist under a doctor’s supervision will help in performing the NCS.
How long does an EMG take?
The test typically takes between 40 to 60 minutes, depending on the complexity of the case. Please always arrive at least 15 minutes before your scheduled appointment to allow sufficient time for any preparation