Spinal Stenosis Q & A
Spinal Stenosis Q & A
Spinal Stenosis Q & A
& Answers
about . . .
Spinal
Stenosis
You can also find this booklet on the NIAMS Web site at
www.niams.nih.gov/hi/topics/spinalstenosis/spinal_sten.htm.
Spinal Stenosis
Table of Contents
1
Figure 1
Cervical
(7)
Thoracic
(12)
Vertebra
Lumbar Intervertebral disk
(5)
Sacrum
Cauda equina
Coccyx
Figure 2
Spine
Ligamentum flavum
Vertebral foramen Vertebral arch
or spinal canal
Lamina
Spinal cord
Facet joint
Pedicle
Nerve root
Posterior longitudinal
ligament
Intervertebral disk
Anterior longitudinal
ligament
2
Spinal Stenosis
column of 26 bones
that extend in a line Spinal cord
cervical vertebrae in
the neck; 12 thoracic vertebrae at the back wall of the chest;
5 lumbar vertebrae at the inward curve (small) of the lower
back; the sacrum, composed of 5 fused vertebrae between
the hip bones; and the coccyx, composed of 3 to 5 fused
bones at the lower tip of the vertebral column. The vertebrae
link to each other and are cushioned by shock-absorbing
disks that lie between them.
3
The vertebral column provides the main support for the
upper body, allowing humans to stand upright or bend and
twist, and it protects the spinal cord from injury. Following
are structures of the spine most involved in spinal stenosis.
(See figs. 1, 2 and 3, and fig. 7 on p. 11.)
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Spinal Stenosis
5
What Causes Spinal Stenosis?
stenosis, may be
Normal Vertebra (Cross Section)
inherited or acquired.
Some people inherit a
small spinal canal (see fig. 5) or have a curvature of the
spine (scoliosis) that produces pressure on nerves and soft
tissue and compresses or stretches ligaments. In an inherited
condition called achondroplasia, defective bone formation
results in abnormally short and thickened pedicles that
reduce the diameter (distance across) of the spinal canal.
Degenerative Conditions
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Spinal Stenosis
Figure 5 Figure 6
Degenerated
facet joints
Small
spinal canal
Herniated
disk
7
birth. Poor alignment of the spinal column when a vertebra
slips forward onto the one below it can place pressure on the
spinal cord or nerve roots at that place.
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Spinal Stenosis
9
the spine. The blood supply that feeds healthy
nerve tissue may be diverted to the area of
involved bone. Also, structural problems of the
involved vertebrae can cause narrowing of the
spinal canal, producing a variety of neurological
symptoms. Other developmental conditions may
also result in spinal stenosis.
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Spinal Stenosis
Figure 7
11
experience numbness, weakness, cramping, or general pain
in the arms or legs. If the narrowed space within the spine is
pushing on a nerve root, people may feel pain radiating
down the leg (sciatica). Sitting or flexing the lower back
should relieve symptoms. (The flexed position “opens up”
the spinal column, enlarging the spaces between vertebrae at
the back of the spine.) Flexing exercises are often advised,
along with stretching and strengthening exercises.
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Spinal Stenosis
13
scan shows the shape and size of the spinal canal, its
contents, and structures surrounding it.
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Spinal Stenosis
2 Brand names included in this fact sheet are provided as examples only. Their
inclusion does not mean that these products are endorsed by the National Institutes
of Health or another government agency. Also, if a particular brand name is not
mentioned, this does not imply that the product is unsatisfactory.
15
and back muscles, and build endurance, all of which
help stabilize the spine. Some patients may be
encouraged to try slowly progressive aerobic activity
such as swimming or using exercise bicycles.
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Spinal Stenosis
17
The purpose of surgery is to relieve pressure on the spinal
cord or nerves and restore and maintain alignment and
strength of the spine. This can be done by removing,
trimming, or adjusting diseased parts that are causing the
pressure or loss of alignment. The most common surgery is
called decompressive laminectomy: removal of the lamina
(roof) of one or more vertebrae to create more space for the
nerves. A surgeon may perform a laminectomy with or
without fusing vertebrae or removing part of a disk. Various
devices may be used to enhance fusion and strengthen
unstable segments of the spine following decompression
surgery.
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Spinal Stenosis
19
What Are Other Sources of Information on Spinal
Stenosis?
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Spinal Stenosis
21
■ North American Spine Society
22 Calendar Court, 2nd floor
La Grange, IL 60525
Phone: 877–SpineDr (877–774–6337)
www.spine.org
22
Acknowledgments