Spinal stenosis is an abnormal narrowing of the spinal
canal, which is the space between the spinal cord and
the bony structure that surrounds it. If this space
becomes too narrow, the bony structure that surrounds
the spinal cord can press against it and/or the spinal
muscle weakness, loss of sensation, an impaired ability
to coordinate movements, and impairment of the
autonomic nervous system.
The autonomic nervous system is a system responsible for exciting and calming down
the body by increasing and decreasing blood pressure, heart rate, and other important
functions.
How does this narrowing happen? Many times, it is due to an inherited abnormality. That
is, the person is born with a defect in the bony structure that surrounds the spinal cord
such that it does not form enough space around it. Sometimes, the joints of the bones
that surround the spinal cord can stiffen, resulting in a narrower spinal canal. Narrowing
in the spinal canal can also occur due to old age, when the bony structure that surrounds
the spinal cord wears away. Another cause is trauma to the bony structure that
surrounds the spinal cord. When someone has a narrow spinal canal, there is a greater
chance that any disks protruding (sticking out) from the spinal cord will hit against the
bony structure surrounding it, leading to pain.
Spinal stenosis comes from the Latin word "spina," meaning "backbone," the Greek word "stenos"
meaning "narrow," and the Greek word "osis" meaning "condition." Put the words together and you get a
"narrow condition (of the) backbone."