What is electromyography?
Electromyography (EMG) is a diagnostic procedure that evaluates the health condition of muscles and the nerve cells that control them. These nerve cells are known as motor neurons. They transmit electrical signals that cause muscles to contract and relax. An EMG translates these signals into graphs and numbers, helping doctors to make a diagnosis.
There are two parts to EMG testing: a nerve conduction study and a needle exam for muscle testing. Both are usually well tolerated without the need for medication beforehand. The nerve conduction study entails stimulating the nerves at different points with small electric impulses, activating them so their function can be measured. The needle exam involves inserting very fine needles into several muscles. The needle has a microscopic electrode that picks up both the normal and abnormal electrical signals given off by a muscle. EMG testing usually takes anywhere from 30 to 90 minutes. A report that includes the results and an interpretation will be relayed to your doctor.
Here at Regional Neurological, we have doctors with specialty training that are Board Certified and Fellowship trained in these intricate procedures.
Why is electromyography performed?
Our office may request an EMG if you’re experiencing symptoms that may indicate a muscle or nerve disorder. Some symptoms that may call for an EMG include:
EMG results are often necessary to help diagnose or rule out a number of conditions such as:
- Muscle disorders, such as muscular dystrophy or myopathies
- Diseases affecting the connection between the nerve and the muscle, such as myasthenia gravis
- Disorders of nerves outside the spinal cord (peripheral nerves), such as carpal tunnel syndrome or ulnar neuropathy
- Disorders that affect the motor neurons in the brain or spinal cord, such as amyotrophic lateral sclerosis or polio
- Disorders that affect the nerve root, such as a herniated disk in the spine, “pinched nerve” or “sciatica” we can use this information to better decipher if this is a more recent issue (acute) or prior injury (chronic) disorder