A medical professional may have to do an electromyography or EMG when an individual presents with symptoms of a muscle or nerve disorder. Some of these symptoms can include numbness of the fingers, joints, or other muscle areas, tingling sensations, and unexplained weakness of the hind and forelimbs.
Major Advantages Of Electromyography
Many doctors refer to EMG as an electrodiagnostic exam. The name might sound scary but this medical procedure has a lot of merits for any individual who takes it. When done appropriately, EMG results have been seen to help doctors diagnose acute muscle disorders, nerve disorders, and any disorder of any kind, especially those affecting nerve-muscle connections.
The World Health Organisation in one of its articles on EMG noted that the procedure is purely diagnostic. This means it is used to assess the health of muscles and of the nerve cells, also known as motor neurons, that control them
When one takes an EMG examination and the results are released, medical professionals can be able to pinpoint what exactly what wrong with the muscle and/or the nerve, as EMG results can reveal nerve dysfunction or problems with ‘nerve-to-muscle signal transmission’.
Nerve-to-muscle signal transmission, also known as neuromuscular transmission, is a process that permits the central nervous system to control the movement of muscles in the body.
By nature, nerve impulses kick-start the release of a neurotransmitter known as acetylcholine or Ach into the junction between the nerve cell and the muscle cell.
Diseases involving this junction known as the neuromuscular junction are called NMT disorders. This is because they are caused by a dysfunction in the transmission of Ach at the nerve-muscle synapse.
All this is dependent on the site of the dysfunction which is broadly classified into postsynaptic, presynaptic, and a combination of pre- and post-synaptic disorders.
The one proven way to diagnose any of these disorders is through EMG.
Electrical signals are transmitted by motor neurons which cause the muscles to contract. An EMG procedure uses tiny devices known as electrodes to decode these signals into grids, charts, sounds, or numerical values. These values are in turn interpreted by a specialist to give a diagnosis. It is that simple.
In a needle EMG procedure, the device used would be a needle electrode. This device is introduced through an insertion directly into a muscle and activities in that muscle are recorded to get a diagnosis.
For a nerve conduction study, which is also a part of an EMG, electrode stickers or surface electrodes are applied to the skin to measure the speed and strength of the signal traveling between two or more points. These speed signals are read against the chart and a diagnosis is formulated for that individual.
Why Perform Electromyography?
Performing an EMG can be a sure way for a doctor to give the right muscle-nerve disorder diagnosis, especially when there are symptoms such as muscle weakness, tingling, paralysis, numbness, muscle pain or cramping, paralysis and involuntary muscle twitching also known as tics.
When conducted, the results can help the doctor know the underlying conditions responsible for these symptoms and their possible causes.
Doctors are able to diagnose, amongst many others disorders that affect the ability of the motor neuron to send electrical signals to the muscles, which is known as myasthenia gravis.
They can also check for muscle disorders, such as muscular dystrophy, radiculopathies, peripheral nerve disorders that affect the nerves outside the spinal cord area, such as carpal tunnel syndrome, and nerve disorders, such as amyotrophic lateral sclerosis (also known as ALS), amongst other disorders.
Many medical practitioners trust EMG because it is a low-risk procedure. Complications are rare and almost non-existent. There may be bleeding or nerve injury when the needle electrode is inserted but it is generally risk-free.
There is also a very minute risk that may occur when muscles along the chest wall are examined with a needle electrode. It could cause air to leak into the area between the lungs and chest wall causing pneumothorax or lung collapse. This is ultimately rare
When one is ready for an EMG, one is asked to stop taking any prescription or over-the-counter medications before the examination. It is ultimately important to ask the doctor if medications such as Mestinon (pyridostigmine) should be taken before, during, or after the procedure.
The medical professional, mostly a neurologist, will interpret the results of the EMG examination and a report will be prepared.
This would be followed up by another appointment to begin management and treatment.