EMG” is an abbreviation for electromyogram. “Electro” means electric, “myo” means muscles, and “gram” means recording of. “NCV” is an abbreviation for nerve conduction velocity. N for nerve C for conduction, and V for velocity.
The diagnosis of neuromuscular disease hinges on the doctor’s ability to identify specific deficit of defects of neuromuscular function. Sometimes a doctor can infer this functional deficit and the disease associated by a physical examination, doing a blood test and looking at the anatomy of the nerves and muscles. At other times, the doctor may have to directly evaluate the functions of the muscles and nerves and the connections between them by performing the EMG/NCV test.
No special preparation is needed. You may eat a regular meal or snack prior to the test. If you are on medications, take them as prescribed. If you are on blood thinners, inform the physician performing the testing since he may have to modify the needle examination. Please inform the physician if you are pregnant or have a defibrillator pacemaker.
Your EMG/NCV study is a two-part test. The first part involves testing the nerves. Small metal electrodes are taped to your skin. Then an electrical stimulus will be administered to a nerve. The stimulus is just enough to make the extremity (arm or leg) twitch depending on your symptoms. Two to six nerves will be tested and it will take anywhere from 20-45 minutes.
The second portion of the test is to examine the muscles. Muscle activity is tested by inserting a fine tipped needle into the muscle. You will be asked to contract and relax the muscle.
There will be some discomfort during the EMG/NCV study. The discomfort will last for a short period of time.
When the test is completed, you may return to your normal activities. If you still feel some discomfort in the area where the needle was inserted, a warm bath or hot compress and Tylenol should relieve it.
The doctor performing the test will interpret the test results and report them to your referring physician. Your doctor or his staff will notify you of the test results taking into consideration other testing that was performed on you. The abnormalities in the test may indicate the following: Neuropath (nerve damage for diabetes, etc), Muscle disorders (myopathy, muscular dystrophy), entrapment of nerves (Carpal, Cubital Tunnel, etc), or pinched nerves in the neck or lower back (radiculopathy).