Electromyography (EMG) is one of many electrodiagnostic tests performed to study the body’s electrical function.  Although EMG has many different types of transducers and protocols, it can be described as a neuro- and musculoskeletal-specific test Peripheral nervous system pathways.
Electromyography is the process of capturing electrical signals from your muscles with electrodes. An EMG test can provide data about the impulse from the nerve responsible for the contraction and how the muscle fibers respond to that impulse.  Depending on the device used The raw data generated can be exported as a graph called an EMG, hence the name EMG Raw Test in some cases.
Nerve conduction studies (electromyelogram)
An EMG test is usually followed by an electromyogram, also known as an NCS (nerve conduction study). As a more aggressive testing method than EMG NCS, electrical input is included to more specifically observe how the nerves respond. Parameters such as action potential latency amplitude and Conduction velocity was observed with EMG after application of an artificial electrical signal. Data collected from the NCS can be used to determine the type and extent of nerve damage. 
In an EMG, a value called the Motor Unit Potential (MUP) of the target muscle is observed. These are the electrical potentials generated by the muscles to perform voluntary contractions. Then according to the frequency amplitude and generate shrink.
EMG uses the electrophysiological properties of muscle to distinguish myopathy from neuropathy and helps determine the type and progression of these conditions, which may include: 
- Muscular Dystrophies
- pathology affecting nerves or muscles
- Myasthenia Gravis
- Carpal tunnel syndrome and other types of peripheral nerve injury/blockage
Types of EMG
The electrodes are placed within the needle tip, which is inserted into the target muscle and can be repositioned as needed. Needle EMG is the method of choice for diagnostic purposes as it is more specific and reliable than surface electrodes. Although the process is considered safe Due to the use of needles, there are still potential risks of pain, bleeding, infection and pneumothorax. 
Surface EMG (sEMG)
Surface measurements of muscle activity are generally reserved for research purposes. Using adhesive electrodes on the skin in the targeted area can make the test easier. However, a single surface electrode measurement acquires signals from multiple muscle fibers and all tissues in between Impairs signal integrity, rendering it unusable for diagnostic purposes. 
EMG in Rehabilitation
EMG has also found use in some areas of rehabilitation biofeedback therapy being one of them. Modulation of biological actions is a proven concept. This approach has been used successfully in the past for visual and auditory feedback and will Feedback-like EMG has been used with varying degrees of success in coordinating the muscular movements of the pelvic floor muscles.  The same principle holds hope, albeit to a lesser degree, for patients who have recently undergone knee surgery.  Alternative uses of surface variance EMG was also tested to find mixed results, one of which was the inspiratory muscles. 
EMG in Research
Due to the intricate nature of the entire nervous system, the electrophysiological properties of the human body remain an active research topic. EMG has proven to be an invaluable tool for collecting data and has helped to establish some current concepts of the musculoskeletal system in the literature. As research has progressed, the use of EMG in conjunction with other types of electrodiagnostic tools has led to numerous studies discovering and evaluating new methods of rehabilitation, such as motor imagery and sensory feedback.  Research aimed at applying EMG to more Specific areas such as activities of daily living are also prevalent, especially with the advancements in EMG technological transformation. 
Technological Research and Development
Due to the multidisciplinary research on the subject EMG has not remained the only clinical trial. From gait analysis  to man-machine wheelchairs with EMG sensors , this technology proved to be an exciting prospect. This power also paved the way for sensor technology to become more accessible and cost-effective.  .
While it is impossible to deny the fact that objective problems undoubtedly increased in proportion to the ease with which these devices were available , they also brought many new areas and approaches to life in cosmetics just like 3d printing technology.
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