02/27/2026
We are often asked what is an EMG?
We put together a brief information sheet to help you understand what an EMG is , whether you are having a test with us or someone else. We hope this helps.
What is an EMG/NCS? What information can be obtained (or not).
• Nerve Conduction Study (NCS): This test measures how fast and how well electrical signals travel through your nerves. It is used to identify nerve damage or compression.
• Electromyography (EMG): This test evaluates the electrical activity produced by your muscles both when they are at rest and when they are active. It helps detect muscle dysfunction and whether muscles are responding correctly to nerve signals
What to Expect During the Procedure
1. NCS: small electrodes are placed on your skin. The doctor applies a mild electrical pulses to the nerve, which may cause a brief tingling sensation or muscle twitch, due to activation of the nerve
2. EMG: A very thin, sterile needle is gently inserted into specific muscles. This needle acts like a microphone to "listen" to the muscle's natural electrical activity while you relax and then slowly contract the muscle. No electrical shocks are given during this part of the test.
Conditions These Tests Can Help Diagnose
These tests are instrumental in identifying various neurological and muscular conditions, including:
• Nerve Compression (that is causing damage): Such as Carpal Tunnel Syndrome or damaged nerves from neck or back.
• Neuropathies: Nerve damage often related to diabetes or other medical conditions.
• Spinal Nerve Issues: Such as a herniated disc causing a damaged nerve in the neck or low back.
• Muscle Disorders: Conditions like Muscular Dystrophy, Myopathy, others.
• Neuromuscular Junction Disorders: Such as Myasthenia Gravis.
• Motor Neuron Diseases: Such as ALS.
Patient Preparation
• Skin Care: Do not use any lotions, creams, or oils on the day of the test, as these can interfere with the electrodes.
• Clothing: Wear loose, comfortable clothing that allows easy access to your arms and legs.
• Medical History: Inform the doctor if you have a pacemaker, take blood thinners (like warfarin), or have a bleeding disorder. Pacemaker is not a contraindication to testing. Blood thinners can result in increased risk of bleeding and bruising.
• Other information: you may notice some small bruises from the needles; this may be worse if you are on blood thinners
• Recovery: you may have some mild soreness or an aching feeling after, generally this does not last long but if needed you may take your pain reliever of choice.
• Please understand: this test does not measure your pain but may identify nerve injury that may contribute to your pain. This test also does not measure or assess bursitis, tendonitis, arthritis, or several other conditions that may contribute to your symptoms. If your test is normal, that does not mean you aren’t having pain, simply that at this time this test cannot determine the source and helps your doctors know what is not a factor currently. This test can also change over weeks if/when injury or damage is progressive, so a normal today does not mean this test will remain normal in the future, it can change and at times we do recommend repeat studies if worsening symptoms.
