Neurology is a branch of medicine dealing with disorders of the nervous system. The practice heavily relies on the field of neuroscience, a scientific study of the nervous system. Neurologists specialize in investigating, diagnosing, and treatment of conditions and diseases involving the central and peripheral nervous systems, including their subdivisions: autonomic nervous system and the somatic nervous system. Neurology deals with the coverings, blood vessels, and all effector tissue, such as muscle of these systems.
Nerve testing is done to diagnose abnormal nerve functions. It is used to determine nerve injury location, severity of nerve conditions, and how nerves may be responding to treatments. An Electromyogram (EMG) detects electrical activity in muscles that occurs from nerve stimulation. Electrical activity is a good measure of muscle activity; problems with nerve activity will cause abnormal electric currents, resulting in abnormal muscle function. A Nerve Conduction Study (NCS) may be done at the same time to locate nerve damage.
WHY EMG AND NERVE CONDUCTION STUDIES ARE PERFORMED
EMGs will help a doctor determine the possible causes of a variety of muscle abnormalities. Symptoms that may cause a doctor to perform an EMG, usually accompanied by a Nerve Conduction Study, include:
- Chronic or acute pain
- Tingling and Numbness
- Cramping or Spasms
- Pain in certain limbs
CONDITIONS & SYMPTOMS
The EMG and Nerve Conduction Studies will either rule out or pinpoint a problem or medical condition that may be occurring in the nerve paths along a patient’s muscles. These most commonly include:
- Peripheral nerve damage (arms and legs)
- Thoracic outlet syndrome
- Peripheral nerve disorders, such as carpal tunnel syndrome
- Muscular disorders, such as muscular dystrophy
- Disorders of motor neurons, such as sclerosis or polio
- Disorders in nerve roots, such as a herniated discs
- Inflammation of muscles
- Diseases of muscle nerve roots, such as myasthenia gravis
- Pinched nerves (radiculopathy) or nerve compression
PROCEDURE: EMG AND NERVE CONDUCTION STUDIES
During a needle EMG, an electrode needle is inserted directly into the muscle to record electrical impulses. These electrode needles detect electrical signals transmitted by motor neurons. Motor neurons use the electrical impulses to control muscle relaxation and contraction. The EMG will transform the electrical patterns into graphs or audio that the doctor specializes in interpreting. The patient may be asked to contract and relax muscles while the needles are inserted. The doctor will be able to recognize what the abnormal impulses could be caused by, diagnosing nerve or muscle dysfunction or dysfunction in the communication between muscle and nerve. Nerve Conduction Studies are often done at the same time with electrodes taped to the skin. They will stimulate electric currents down nerve paths to determine how fast they are able to travel. This often locates peripheral nerve damage.
AFTER THE PROCEDURE
The EMG needles may cause slight discomfort, soreness, or bruising. These side effects do not last more than a few days. A doctor will read the results of the EMG and Nerve Conduction Studies and diagnose the source of the patients’ symptoms. With a proper diagnosis, treatment options can then be discussed. Your doctor will determine the best form of treatment for you after analyzing the results of your tests.