Electromyography
(EMG)

Electromyography, or EMG, is a test that checks how your muscles and nerves are working. It has two parts: a nerve conduction study, which measures how well electricity travels through nerves, and a needle EMG, which records signals your muscles make during movement. Together, the results help doctors detect problems linked to certain conditions. (Learn about related testing in our Nerve Conduction Study.)

Your doctor may recommend an EMG if you have symptoms like weakness, tingling, or unexplained muscle pain. The test shows whether these issues are caused by problems in your nerves or muscles. By identifying how electrical activity functions, your physician gains insights that guide the next steps in your treatment. (See more care options under Pain Management.)

An EMG includes both a nerve conduction study and a needle electromyogram. The nerve conduction study measures how well signals pass through your nerves. The needle portion records the signals your muscles create during movement. Together, they provide valuable information about how nerves and muscles are functioning. (Learn about supportive recovery care in Physical Therapy.)

The nerve conduction study measures how electricity moves through nerves. Small impulses are applied, and the responses are recorded to see if your nerves conduct signals normally. This part of the EMG shows whether your nerves are functioning properly or if damage or dysfunction is present. (Explore other diagnostic tools like Diagnostic Testing for Mild TBI.)

The needle electromyogram records the electrical signals your muscles make when you move. By studying this activity, doctors can see if your muscles respond normally or if they’re affected by nerve-related conditions. This part of the test helps detect problems that may not appear on standard imaging scans. (See additional care options in Orthopedics.)

EMG results help doctors decide whether your symptoms are linked to nerve or muscle disorders. Abnormal findings may confirm the presence of conditions that need treatment. By combining both parts of the test, physicians get a clearer picture of your neuromuscular health and how to move forward with care. (Learn more under Injury Care.)