Electromyography (EMG) and nerve conduction studies can diagnose muscle and nerve issues that may be otherwise difficult to diagnose.
Nerves and muscles naturally produce electricity. An electromyography (EMG) and nerve conduction study measures the electrical activity created by your muscles and nerves to determine if they are healthy.
Some nerve and muscle issues (also called "neuromuscular") may be difficult to diagnose. Often, a physical exam and/or blood tests alone cannot provide a diagnosis. An EMG and nerve conduction study can help.
Conditions and Symptoms Diagnosed With EMG at Rush
An EMG and nerve conduction study can help diagnose the following conditions and symptoms:
- Amyotrophic lateral sclerosis (ALS)
- Carpal tunnel syndrome and other entrapment neuropathy
- Diabetic neuropathy
- Peripheral neuropathy
- Muscular dystrophy
- Myasthenia gravis
- Numbness or loss of feeling
- Muscle weakness
- Muscle pain, cramping or twitching
EMG and Nerve Conduction Study: What to Expect at Rush
- The test typically has two parts that are performed in the same setting: the nerve conduction study and electromyography study.
- The entire test usually takes about 1.5 hours total. It may be shorter or longer depending on your condition.
Nerve Conduction Study
- Rush technicians or doctors will place electrodes on your skin. They will place these over nerves and muscles that may be involved in causing your symptoms.
- They will then stimulate the nerves, one at a time. They are looking for your nerve or muscle's response.
- They compare the responses to what is considered "normal" to determine the health of your nerves and muscles.
- Rush technicians or doctors will insert a thin needle electrode into muscles, one at a time, that may be involved in your symptoms.
- They will then ask you to either relax or activate the muscles. For example, they may ask you to relax or bend your elbow, relax or push down with your foot, etc.
- Your doctor will use these actions to analyze your muscles when they are at rest or being active.
Is an EMG or Nerve Conduction Test Painful?
Your technician or doctor will make every effort to minimize any discomfort you may experience. Most patients do not experience significant discomfort or side effects.
- Nerve conduction study: These feel like static electricity or like a rubber band slapping against your skin. You may feel your muscles twitch.
- EMG study: You may feel some discomfort or pain when the doctor inserts the needle into the muscle.
- Potential side effects: There may be bruising and/or soreness of the muscle for one or two days after the test.
EMG and Nerve Conduction Study Test Results
- The doctor who performs your test may be able to explain some of your test results before you leave. But this is not always possible. These tests are highly technical and often need to be thoroughly reviewed by the doctor who ordered them before a final conclusion.
- After your test, the next step is to follow up with the doctor who ordered the tests. You'll discuss your condition, treatment options and any further testing needs with them.
Rush Excellence in EMG and Nerve Conduction Studies
- Diagnostic expertise: Rush providers are skilled at using EMG and nerve conduction studies to identify the cause of your nerve and muscle issues. The sooner you have a diagnosis for your issues, the faster you can start addressing the underlying condition.
- Providers across the system: If you are experiencing nerve or muscle pain or weakness, Rush has general neurologists, physical rehabilitation physicians and neuromuscular disease specialists who can help. These specialists can order an EMG and nerve conduction study to identify the cause and recommend next steps based on your diagnosis.
- Coordination with Rush specialists: Depending on your diagnosis, these providers can connect you to another Rush specialist as needed for treatment. For example, if your nerve or muscle issues are related to a neuromuscular disease, such as ALS or muscular dystrophy, they will refer you for further specialized treatment.
- Nationally recognized expertise: The neurology and neurosurgery program at Rush University Medical Center is consistently ranked among the best in the country in U.S. News & World Report. And the neurology EMG lab at Rush University Medical Center has been recognized as "exemplary" by the American Association of Neuromuscular and Electrodiagnostic Medicine.