What is EMG/NCS?
Electromyography (EMG) has several components. The most frequently encountered tests are:
Needle EMG, nerve conduction studies
Needle EMG involves testing selected muscles to help establish any abnormality present. A very small (thin) needle is inserted into each muscle selected. The needle is connected to a computer, which provides information for the doctor conducting the test to interpret.
A few patients occasionally experience some discomfort when the needle is inserted. However, most patients tolerate the procedure very well. One disposable sterile needle is used for the test. Generally, each patient requires only one or two parts of the test.
Nerve Conduction Studies (NCS)
During nerve conduction studies, your EMG doctor will test different nerves to determine if they are conducting the body’s electrical activities normally. You will be connected to a computer (EMG machine) and the nerve being tested will receive very small electric shocks.
The electric shocks received are not harmful. Patients may feel some mild tingling or shock. Occasionally few patients experience some discomfort when the shocks are applied. However, most patients tolerate the procedure very well.
Evoke potentials test the nerves that pass through the spinal cord. You will also be connected to an EMG machine and have very small shocks applied to the nerves being tested, being stimulated by light or sound. The responses generated are recorded from the scalp/skin and transferred to a computer where it can be analyzed and interpreted by your EMG doctor.
Your EMG Doctor – Electromyographer
Your EMG doctors are typically MD’s or DO’s who have had four years of medical school training, a year of internship and specialty training in physical medicine and rehabilitation (also called physiatry) and neurology.
During residency training some EMG training is often acquired. After the completion of residency, some physiatrists and neurologists complete additional training in the form of a fellowship in EMG to expand on the limited training obtained in residency.
Preparing for the EMG Test
The test may last from 20 minutes to about two hours. You can continue your normal activities, including any restrictions prior to the test. There are no special precautions required. However, it is very important that you inform your EMG doctor if you have a bleeding disorder, if you are taking any blood thinning medication or if you have a pacemaker.
Your EMG doctor will also perform a history and physical examination prior to the test. After your EMG test is completed you may resume normal activities unless instructed otherwise by your EMG doctor. There are no expected side effects from the test. The test results will be discussed with you or sent to your primary care/referring physician.