Electromyography (EMG) is a diagnostic test that helps evaluate the health and function of nerves and muscles. The test is performed by inserting thin needles through the skin and into the muscles. The electrodes on the end of the needles measure electrical activity in the muscles. EMG test is used to diagnose injuries, muscle disease and neuromuscular disorders. A nerve conduction study, a part of EMG, helps diagnose nerve damage or disease.
An EMG is done if any signs and symptoms suggestive of nerve and muscle disorder are present. These include tingling, numbness, muscle weakness, muscle cramps, involuntary twitching or paralysis of any muscle. The results of an EMG can help in diagnosing the underlying cause of these signs and symptoms. Probable causes include muscular dystrophy, disorders affecting the ability of motor neurons to transmit electrical signals, peripheral nerve disorders like carpal tunnel syndrome and nerve root disorders like herniated disc in the spine.
While conducting this test, an EMG specialist, needle electrodes are inserted through the skin into the muscle or muscle groups. These electrodes record electrical activity in the muscles in response to nerve stimulation, which help in pinpointing damaged nerves. There may be some discomfort due to insertion of the needle electrodes and muscle soreness that lasts for a day or two after the test. The Centre for Neurosciences at Kokilaben Dhirubhai Ambani Hospital, Indore has one of the best EMG test Centre in Indore. The centre has some of the best neurologists in Indore who carry out all the tests keeping the patient comfort in mind.
A Nerve Conduction Study measures the speed at which impulses are transmitted between two or more nerves. Electrode stickers are applied to the skin along the pathway of the nerves to be tested. A low electrical impulse is sent through the electrodes to stimulate the nerves. The speed at which the electric current is transmitted is recorded by the electrodes. A damaged nerve transmits electrical impulses slowly as compared to a healthy nerve. The external electric impulse feels like a shock, but there is no pain or discomfort after the test.
Evoked potentials are specialized studies that measure responses to visual, auditory and electrical stimuli.