Electromyography

Electromyography or EMG is a diagnostic test that understands the physiological of muscles thereby assessing their health. Electromyography involves inserting a needle electrode through the skin into the muscle. This electorde detects electrical activity in the muscles and nerves controlling the muscles. A patient is asked to flex or contract the muscles so that the response of the muscle to the nerve stimuli is observed. An electromyograph is used to detect and measure electric potential that is generated by the contracting muscles. Other indicators to the proper functioning of the muscles and their corresponding nerves are the size, duration and frequency of electric signals received from them. EMG is often conducted along with a nerve conduction velocity test.

The EMG test is used to diagnose any possible weakness or impaired muscle strength due to neurological problems. Some discorders that can lead to abnormal readings on EMG test are cervical spondylosis, myasthenia gravis, carpal tunnel syndrome, myopathy, Brachial plexopathy, Guillain Barre syndrome, sciatic nerve dysfunction and mononueritis multiplex. EMG test aids in differentiating between a muscle and nerve disorder. The muscle may feel tender after the EMG test with localised bruising.