WHAT IS THE PURPOSE OF AN EMG/NCV STUDY?
The purpose of an EMG/NCV study is to provide information to your doctor regarding the health of your nerves and muscles.
This study is typically ordered to assess for damage to the muscles, nerves, or nerve roots.
TYPICAL DIAGNOSES THAT PATIENTS ARE REFERRED FOR ARE:
“Pinched nerves” in the neck or lower spine.
Compression of nerves at commonly injured sites e.g. carpal tunnel, elbow, and knee.
Neuropathies resulting in numbness of the feet and hands like those seen in diabetes.2.
Muscle diseases.
WHAT DOES EMG/NCV STAND FOR?
“EMG” is the abbreviation for electromyography or the study of the electrical activity of your muscles. “NCV” stands for nerve conduction studies where the conduction of your nerves is measured. Most commonly, the EMG/NCV is simply referred to as an “EMG study.”
HOW IS THE TEST PERFORMED? WHAT SHOULD I EXPECT?
NCV: The nerve conduction portion of the test is performed first. While lying in a comfortable position, we will test the ability of your nerves to conduct electrical impulses.
We do this by stimulating the nerves using small electrical shocks and then recording the results. This feels similar to the sensation one perceives when rubbing your feet across the carpet and touching something. The stimulation will cause a quick tingling sensation and cause the tested muscle to twitch. These findings can help us determine the site and extent of any nerve damage.
EMG: The EMG portion of the test is performed second and is also performed while you are lying down in a comfortable position. During this portion, the electrical activity of your muscle is analyzed using a specialized recording needle and sophisticated computer monitoring.
This is performed using a tiny recording needle that is inserted into the muscles themselves (a series of muscles are usually examined) and the electrical activity is then assessed while you gently flex each muscle.
If abnormal signals are found, this can help localize the site of injury, assess severity, and judge how long the damage has been going on.
IS THE TEST PAINFUL?
The test can be uncomfortable for some patients; however, the vast majority of patients say that the test was “not nearly as bad as they expected.” The nerve conduction electrical shocks will cause a brief tingling sensation and will make certain muscles twitch. The EMG needle is sharp and feels like a tiny shot or beesting. There is no electric shock associated with the quick needle insertion.
It is simply a passive recorder – think of it as a tiny microphone. Relaxation is the key. Patients almost never need sedatives or pain medications. Your EMG physicians have each undergone this type of testing multiple times during their careers and understand what you are feeling. We will do everything possible to make it as comfortable and effortless as possible.
WHAT CAN I DO TO PREPARE FOR THE TEST?
Relax – this test should not be a stressful event. We’ll do our best to make it as pleasant as possible.
For studies of the arms, please consider wearing a tank top shirt so that your nerves and muscles can be easily accessed. Similarly, for studies of the legs, comfortable gym or running type shorts work best.
Please avoid wearing lotions or oils on the day of the test. These types of lotions make it very difficult for the recording electrodes to adhere to the skin.
You can take your prescribed medications as usual on the day of the test. Please let us know if you are on anticoagulants such as heparin or Coumadin.
IT IS O.K. TO EAT AND DRINK PRIOR TO THE TEST?
A typical study takes between 30-60 minutes, so plan on using the restroom on your way to check- in.
WHAT CAN I EXPECT AFTER THE TEST?
It is not unusual to experience some minimal soreness or small bruising at the EMG needle sites; however, you will be able to return to your normal activities as soon as the test is completed. This minor soreness is short-lived and does not bother most patients.
If symptoms persist, the soreness responds well to ice or Tylenol. In most cases, the examiner will give you the preliminary results prior to discharge.
The final report will be forwarded to your referring physician.
If for any reason, your referring physician does not have the report at the time of your follow-up visit, that office can call us directly and we’ll FAX it over immediately.