What is electromyography?
Motor neurons are nerve cells that stimulate the muscles through signals. This stimulation causes electrical activity to be sent to the muscles, allowing them to contract or tighten. When damage occurs to the motor neurons, this can impact their communication with the muscles.
Electromyography (EMG) is a test that looks at how well your child’s muscles and nerves work together. The test measures the response of muscles and nerves to electrical activity. It can help your child’s health-care team diagnose conditions that may cause muscle weakness or damage to nerves.
An EMG may tell:
- if your child has a problem with the nerves or muscles
- why their muscles feel weak, stiff or painful
- where the problem is
EMG (Electromyography) and NCS (nerve conduction study)
Your child may meet the following team members at the time of their appointment:
- Technologist: A technologist operates electromyographic equipment. They assist your child’s health-care team in diagnosing neuromuscular conditions.
- Neurologist: A doctor who has had extra training in the care of children with neurological conditions and concerns. The neurologist is responsible for overseeing the medical care of your child. Often, the neurologist will interpret the EMG results and send them back to your child’s health-care provider.
- Nurse practitioner: An advanced practice nurse who has education and training in providing some aspects of medical care to your child such as diagnosing, prescribing medications and ordering tests. You may meet the neuromuscular nurse practitioner during your child’s EMG appointment.
Your child’s health-care team may do different assessments on the day of their appointment. Some of these assessments test for problems with only the nerves, or both the nerves and muscles:
- Electromyography (EMG) needle test: An EMG needle test is done to assess for muscle health and can look at the communication between the muscles and the nerves. For this test, the technologist will place a small needle into the muscle. The signal from the muscle is then transmitted through the needle to an amplifier so the response can be heard and then to the monitor of a machine so the response can be seen. This will help your child’s health-care team see and hear if there is a problem with the communication between the muscles and the nerves. This is a low-risk procedure and complications with an EMG are rare.
The health-care team will always tell you and your child when and where they will put the needle. Putting the needle in the muscles may hurt a little, just like it does when your child gets a regular needle. Numbing cream is placed on any areas where the needle will be inserted, to keep your child as comfortable as possible. - Nerve conduction study: This test is done to assess the health of the peripheral nerves. Read the article about nerve conduction studies to learn more about this test.
Preparing for an EMG
We encourage all families to speak with their child about what to expect on the day of the test. It is important that children are prepared and empowered to ask any questions they may have.
Here are some other things to keep in mind when preparing for the EMG:
- Your child should wear loose, easy to remove clothing on the day of the test.
- Your child should not use lotions or creams on the day of testing.
- Your child should bring a comfort item with them such as a favourite stuffed animal or blanket.
- There is no need for your child to stop any scheduled medications. This test does not require fasting.
After your child’s EMG
After the EMG, your child can return to normal activity. The muscles that were tested might hurt a little for a short time after the test, but there should be no complications with recovery.
The test results will be sent to the health-care provider who sent your child for the test so that they can explain the results to you. This will be communicated to you and your child during the appointment.