Electromyography Testing - EMG

Some conditions require specialized testing for proper diagnosis. One study, EMG/NCS can be performed in the office via the use of highly sophisticated computerized equipment. Dr. Rosenberg has performed thousands of these studies to diagnose carpal tunnel syndrome, cervical and lumbar radiculopathies, diabetic neuropathy, etc. This study can be scheduled at Dr. Rosenberg’s Office.

Electromyography (EMG) is a form of electrodiagnostic testing that is used to study nerve and muscle function. Commonly performed by a physiatrist or neurologist trained in this procedure, EMG testing can provide your doctor with specific information about the extent of nerve and/or muscle injury and can also determine the exact location of injury and give some indication whether the damage is reversible.

An EMG is often performed when patients have unexplained muscle weakness. The EMG helps to distinguish between muscle conditions in which the problem begins in the muscle and muscle weakness due to nerve disorders. The EMG can also be used to detect true weakness, as opposed to weakness from reduced use because of pain or lack of motivation. EMGs can also be used to isolate the level of nerve irritation or injury.

EMG’s can be used to detect abnormal electrical activity of muscle that can occur in many diseases and conditions, including muscular dystrophy, inflammation of muscles, pinched nerves, peripheral nerve damage (damage to nerves in the arms and legs), carpal tunnelsyndrome, disc herniation and others.

A nerve conduction velocity (NCV) test is often done at the same time as an EMG. In this test, the nerve is electrically stimulated while a second electrode detects the electrical impulse ‘down-stream’ from the first. This is usually done with surface electrodes that are placed on the skin over the nerve at various locations. One electrode stimulates the nerve with a very mild electrical impulse. The resulting electrical activity is recorded by the other electrodes. The distance between electrodes and the time it takes for electrical impulses to travel between electrodes are used to calculate the speed of impulse transmission (nerve conduction velocity). A decreased speed to transmission indicates nerve disease, such as seen in diabetic polyneuropathy.