What is an EMG?

The first time I was scheduled for an EMG (Electromyography) I was terrified. I must say, my primary care physician did not help much. When I asked her what sort of test it was she explained that it is a test designed to discover the functionality of the muscles and nerves in the extremities of my body. She then volunteered “it’s not exactly torture.” That was not terribly helpful information, and I could have done without that last bit.

So, for those of you who are wondering what an EMG is, and want to know exactly what will happen and what you will experience, I will provide a fairly simple explanation of the test, and share with you my experience while undergoing it. Your response may be slightly different from mine if you are more or less sensitive to stimulus than I am, but it should be fairly well with in the ballpark of my experience. That is unless you have some impairment in your nerves or muscles. If that is the case, then your experience may be far less uncomfortable.

I will start by saying that from my perspective, having an Electromyograhpy/EMG is not painful. I found it to be uncomfortable, and more disconcerting than anything else. You begin by changing into a hospital gown so that your arms and legs are exposed (coming prepared with shorts and a t-shirt might get you out of the gorgeous gown if the tech is amenable). The test starts with something called as NCV (Nerve Conduction Velocity) test, which is performed in conjunction with the EMG. The NCV tests the speed of the conduction of electricity through a nerve. You will then lie down on a gurney or bed in the EMG Suite, and the tech will then place some electrodes on the back of one of your hands and circular clamps around two of your fingers. The clamps do not pinch. The EMG tech then measures the distance from the clamps to a certain point on the inside of your arm, and mark that spot with a pen. Then, using a device that looks like a large pager with two knobs sticking out on one end, he will touch your arm with the two knobs at the top of your wrist, where he had made the mark, and begin to send electricity into your arm. The pulses will be quite faint at first, and he will gradually increase the strength of the current until it comes to a very unpleasant level, and your hand is jumping up and down on the bed.

It takes some time to get used to, but the beginning is by far the hardest. I found my self acclimating to the feeling of having lord knows how many volts pulsed through my wrist and hand. It also helped that the tech kept me talking and asked me very detailed and thought provoking questions that required me to concentrate on my answers and explain what I meant (these were questions unrelated to the test). This was a very efficient way of keeping me just a little bit distracted by what was happening.

The NCV teat was performed on all four of my extremities, and then it was time for the EMG. At this point the attending EMG physician will come into the room and determine if and where you need to have the EMG determined. The decision will be made based on the results of the NCV. If there were some abnormalities in the responses of your nerves to the electric stimulus, more investigation will be warranted, and the EMG will be performed. (If everything checks out normal, you’re done!)

The EMG is a needle electrode that is inserted through the skin and into the muscle. It is used to detect electrical activity in the muscle. The needle is very thin, about the size of an acupuncture needle. If you are unfamiliar with acupuncture needles, think of it as being about the same diameter as a course hair. I had the EMG performed on my right arm and shoulder. The doctor moved the needle up and down in the muscle, and a static sound could be heard coming from the computer the electrode needle was connected to. This was the sound of my muscles firing up. The doctor then asked me to tense and relax certain muscles so she could see their response to the electrode.

The needles were so small, all I really felt was a slightly sore sensation with a bit of pinching when I changed the tension in my muscles. On the whole, I found the EMG to be less uncomfortable and invasive than the NCV, and much shorter. The NCV took over an hour to perform, and the EMG was finished in about 10 minutes.

Regardless of the uncomfortable sensation, the EMG/NCV is an extremely beneficial and informative test, and despite my apprehension, I am very pleased that I had it performed. One of the most satisfying things about the test is that the tech and attending physician can tell you their findings as you go along. There is no waiting for blood test results or for the radiologist to read the scan, it’s just two people looking into a computer and telling you exactly what they are seeing. You will walk out of the test with information that will help you to diagnose or rule out what ever is going on to warrant the test.

So, while my experience with the EMG test was not what I’d call fun, I will give some credence to the words of my former primary care physician. It wasn’t exactly torture. In fact, it wasn’t so bad at all.