Let’s say that you have some sore or weak muscles and they have been feeling this way for a while and they don’t seem to be getting better. You might even have some tingling in these muscles as well. While it may be natural to have soreness or numbness in a muscle once in a while (you might strain a wrist muscle lifting something heavy for example) typically those aches/pains resolve within a few days or weeks. For many people, though, these types of pains are caused by an injured nerve, not an injured muscle. When it’s not clear why you’re having problems with your wrist, back, legs, or other body part, that is when an EMG/NCV test can be very helpful. Since your muscles move when nerve signals from the brain tell them to get to work, Electromyography will measure how well your muscles are responding to those signals. These tests can be a great diagnostic tool for PTs and Physicians to help figure out exactly what is causing these issues. This allows them to determine the best course of action for your treatment to see the best possible results which can help save you time and money!
What is an EMG/NCV study?
Electromyography and Nerve Conduction Velocity (EMG/NCV) determines if your symptoms may be caused by a problem with a nerve. This test can help evaluate the origin of pain, weakness, or numbness and tingling caused by conditions such as nerve compression (example: Carpal Tunnel Syndrome), Peripheral Neuropathy, Sciatica, lower back or neck pathology.
The EMG/NCV is a two-part test. The EMG records the electrical activity inside the muscle and the NCV test records how fast your nerves conduct. If there is a problem with either your muscles or nerves, the EMG/NCV is often able to detect the location and severity of the problem. NCS can also help your doctor see how well you’re recovering from a nerve injury.
What should I expect?
EMG testing involves a Physical Therapist with an advanced EMG certification. They will place a very thin sterile needle electrode into your muscle to record the muscle signal. You may have mild and temporary discomfort with needle insertion. Typically, several muscles are examined. Nerve conduction testing involves an external electrode pad that is placed over the skin to record a low intensity electrical current delivered to the nerve through your skin. The level of current used is not harmful. The recorded response will help determine abnormalities. The tests take around an hour to complete.
If you have any questions about the test or the testing process please do not hesitate to give us a call. We would be more than happy to answer any questions that you might have!
Will the study hurt and are there risks involved with the EMG/NCV study?
During the NCV portion of the test, you will feel a very brief, small “shock” which will make your muscles twitch. While this is an unusual sensation, for most people, it is not uncomfortable. The EMG portion of the test may produce slight momentary discomfort. There may be mild, temporary bruising under the skin if one bleeds or bruises easily. Please notify the examiner if you have a bleeding disorder, are taking a blood thinner, or have a pacemaker.
Your doctor may order an EMG test if you experience any of the following symptoms:
- decreased sensation
- tingling or frequent feeling of "pins and needles"
- radiating pain or burning sensation
- muscle spasms or weakness
- difficulty performing daily tasks such as walking, buttoning clothes or handling objects
What do I need to do before and after the study?
Please do not apply any oils or lotion to the skin of your affected body parts on the day of the test. You may eat and take any necessary medications prior to the test. After the test, there are no limitations. You may drive and return to work.
What should I wear?
If your legs or back are to be tested, please wear or bring along a pair of shorts. If your arms or neck are to be tested, please wear or bring a loose fitting short sleeve shirt.