PE934 Electromyography (EMG) and Nerve Conduction Studies (NCS)

Electromyography (EMG) and Nerve Conduction Studies (NCS)

Electromyography (ee-lek-tro-meye-OG-rah-fee), or EMG, tests the electrical activity of muscles. The purpose of the test is to see how well your child’s nerves and muscles are working. EMG is often done with another test, called a nerve conduction study (NCS). This measures how well signals travel along a nerve.

Why do we do These tests can help your child’s healthcare provider find problems with the these tests? muscles and nerves. If they test a few different muscles, it can also help them to find out about where the problems are in your child’s body. EMG and NCS are also called electrodiagnostic (ee-lek-tro-dye-ug-NOSS- tik) testing. Your child’s healthcare provider might order these tests if your child has any of these: • Numb or tingling feeling in parts of their body • Weak, twitching or painful muscles • Seeing double • Droopy eyelids • Other signs of muscle or nerve problems

How do I prepare The testing usually takes 1 to 2 hours if your child gets both an EMG and an my child for the NCS. Your child can do any regular activities before and after the test. test? During the testing, most children like to have their parents or caregivers in the room. There is not enough room for any other family members to be in the room during the test. Please arrange childcare for brothers and sisters in advance. Seattle Children’s does not offer childcare. The testing can be uncomfortable, but any pain or discomfort should go away within a couple of days. On the day of the test (EMG or NCS), your child should: • Take a bath or shower so their skin is clean. • Avoid using any creams or lotions. These can affect test results. • Wear a loose-fitting short sleeve shirt and shorts. Most of these tests are done on the arms and legs.

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To Learn More Free Interpreter Services • EMG Scheduling • In the hospital, ask your nurse. 206-987-2081 • From outside the hospital, call the • Ask your child’s healthcare provider toll-free Family Interpreting Line, 1-866-583-1527. Tell the interpreter • seattlechildrens.org the name or extension you need. Electromyography (EMG) and Nerve Conduction Studies (NCS)

These are the extra steps to take if your child is having an EMG test: • It is important to tell your child’s healthcare provider in advance about any bleeding disorders or skin infections your child has. • Before the test, talk to your child’s healthcare provider about any medicines that your child is taking. This is especially important if your child takes blood thinners (anticoagulation) such as warfarin (Coumadin), or if your child takes pyridostigmine (Mestinon). • Tell your child’s healthcare provider if your child has a cardiac pacemaker, implantable defibrillator device or transcutaneous nerve stimulator (TENS).

What can my child and I expect during these tests?

Electromyography The doctor doing the test will put a needle electrode through the skin into (EMG) each muscle that we need to test. Electrodes are thin wires that read the electrical signals sent through muscles. The needle is a little smaller than the kind of needle used for shots. It feels about the same, and will probably be uncomfortable for most children. We do not use topical or local anesthetics because they do not help with the muscle pain. Your child will be asked to relax and flex the muscle that we are testing. The electrode reads electrical activity in the muscle. This is shown on a screen or is heard through a speaker or with headphones. Your child may bleed a little where the electrode was in the skin. This area may also feel sore or tender. This does not usually last for much longer than 2 days. It may help to put cold compresses on these areas during the first 4 to 6 hours after the test. Acetaminophen (Tylenol) can also help with soreness. Use this medicine only if recommend by your child’s healthcare provider. Check with the healthcare provider first before giving any type of medicine to your child. It is important to clean your child’s skin where the needle was in the skin to prevent infection.

Nerve Conduction The doctor doing the test will attach a different kind of electrodes to your Study (NCS) child’s skin. These electrodes are like wires that attach to the surface of the skin. When these are attached, we will use a hand-held device to send electric pulses to the nerve. Each pulse lasts only a split second—faster than an eye can blink. The electrodes will then measure how the pulse travels along the nerve. This will be done a few times on each nerve path to make sure we have the right results. We may do the test on more than one nerve. The pulses might cause a short, mild tingling feeling, like a static charge. This can sometimes be uncomfortable, but it lasts less than a second each time the electric pulse is sent.

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How can I find out When the testing is finished, the doctor who does the tests will analyze the about the results of results and send them to your child’s referring healthcare provider. Final results are not usually ready on the same day of the test. The report will be these tests? done within 48 hours and the results will be sent to your child’s regular healthcare provider. Your child’s healthcare provider is most familiar with your child’s problems, and they will talk to you about the results of the test and what they mean. The doctor who does the testing can talk to you about their initial findings on the day of the test, but they will not give you medical advice or a diagnosis.

Seattle Children’s offers interpreter services for Deaf, hard of hearing or non-English speaking patients, family members and legal representatives free of charge. Seattle Children’s will make this information available in alternate formats upon request. Call the 4/19 Family Resource Center at 206-987-2201. This handout has been reviewed by clinical staff at Seattle Children’s. However, your child’s PE934 needs are unique. Before you act or rely upon this information, please talk with your child’s healthcare provider.

Patient and Family Education | Neurology 3 of 3