Muscle and Nerve Tests: Electrodiagnostic Tools

Electromyography (EMG) and Nerve Conduction Velocity (NCV) studies are two types of electrodiagnostic tests.  Electro refers to the electrical impulses in your body and diagnostic refers to the purpose of these tests: to evaluate the function of muscles (EMG) and nerves (NVC).  Although either test can be performed alone, sometimes it is necessary to perform both.

When does Dr. Colon suggest an EMG and/or NVC?

Sometimes, during a patient’s physical and neurological examination, a muscle or nerve problem is suspected to be involved in the cause of pain and weakness.  These tests measure electrical impulses important to function and help pinpoint the origin of a problem.

  • Electromyography measures electrical activity in a muscle.  Tiny needle electrodes are inserted through the skin into one or more muscles or muscle groups.  When stimulated, the electrode measures and records the muscle’s ability to respond.  During the test, the patient may be asked to flex a muscle, or move a body part, such as their arm or leg.


  • Nerve Velocity Conduction involves placing electrode patches onto the skin along a particular nerve pathway.  Low level electrical impulses are delivered through the patches to stimulate a nerve.  The speed of the nerve response is measured and recorded.

Is either test painful?

You may experience discomfort from EMG needle electrode insertion.  Some patients report some discomfort during EMG or NVC.  It is uncommon to feel pain.

Before EMG or NVC

At Newark Rehabilitation Center, we abide by a high standard of care.  Before you undergo electromyography or nerve velocity conduction testing, Dr. Colon’s staff re-reviews your medical history.  If you have a pacemaker, deep brain stimulator or spinal cord stimulator, special precautions are taken.