Electrodiagnostic Testing
Carpal Tunnel Syndrome
Caused by compression
of median nerve in wrist.
Symptoms include pain,
weakness, or numbness
in the hand.
Radiculopathy
Dysfunction/irritation of a
nerve root in the spine.
In the neck, it is called
cervical. In the lower
back, it is called lumbar.
Testing
Often symptoms for the
two types of irritation may
be similar. Testing helps
distinguish them.
Nerve conduction studies define the state of peripheral
nerves. They show how the body's electrical signals are
traveling from one location in a nerve to another. These
calculations are made by taking measurements of the
distance between two sites of stimulation in a nerve and
dividing it by time results seen on the machine.
The tests are performed by applying small electrical
shocks to the nerve and recording how the nerve works.
These shocks cause a quick, mild tingling feeling. The
doctor may test several nerves.
Electromyography helps establish a pattern of
abnormality that fits best with involvement of one or more
nerves, nerve roots, or plexus/collection of nerves. It also
tests for muscle disease. In this portion of the test, a
small, thin needle is inserted into several muscles to see if
there are any problems. A new, sterile needle is used for
each patient, and it is thrown away after the test. There
may be a small amount of pain when the needle is put in.
Only the muscles necessary to decide what is wrong are
examined.
Patients: Please do not use hand or body lotion,
perfumes or colognes, soaps with cream or oils such as
Dove, Tone, Caress on the day of the test. The tests
usually take 60 to 90 minutes. You may perform normal
activities, like eating, driving, and exercising, before and
after the tests. There are no lasting side effects from the
tests.
