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Cervical Stenosis / Cervical Myelopathy
CAUSES
SYMPTOMS
DIAGNOSIS
TREATMENT
Cervical stenosis refers to a lack of sufficient room
for the spinal cord in the neck.
Pressure on the spinal cord or on the blood vessels
of the spinal cord can result in a syndrome known as
cervical myelopathy. Additionally, continual mild trauma
from stenosis can result in myelopathy. Cervical myelopathy
is a form of spinal cord injury that has a fairly classic
clinical appearance. Cervical stenosis can be seen without
signs or symptoms of cervical myelopathy, in fact some
degree of cervical stenosis is common in elderly patients.
Cervical Stenosis / Cervical Myelopathy Causes
Some of the more common causes are congenital spinal
stenosis (a narrowing of the spinal canal that has been
present since birth), bone spurs (sometimes called cervical
spondylosis), cervical disc herniation and thickening
of the various ligaments of the cervical spine. Amongst
the more unusual causes of cervical myelopathy are amyotrophic
lateral sclerosis (ALS, Lou Gerhigs disease),
multiple sclerosis, Chiari I malformation, syringomyelia
(fluid within the spinal cord), blood clot, infection
and tumor. This is only a partial list.
Cervical Stenosis / Cervical Myelopathy Symptoms
Pain is a rare component of cervical myelopathy though
it may be present in cervical stenosis due to pressure
on nerve roots. The same process that causes spinal
stenosis may result in stenosis of the openings in the
spine where the nerves exit. Trouble using the hands
due to weakness may be seen. Difficulty walking due
to spasticity is not uncommon. Urinary troubles, in
particular a feeling of urgency is also common.
Cervical Stenosis / Cervical Myelopathy Diagnosis
As always, a careful history and physical examination
are the first steps in diagnosis. There many possible
causes of cervical myelopathy, most of which will be
distinguished by the history, physical examination and
other testing. Although plain x-rays of the cervical
spine may show evidence of spondylosis and stenosis,
MRI imaging is much better. MRI shows the cause of the
pressure on the spinal cord. It also shows whether or
not spinal cord injury or atrophy is present. Occasionally,
cervical myelogram and post-myelogram CT scans are used.
The post-myelogram CT scan my help define the bone structures
somewhat better than the MRI. Generally, however, the
MRI is the study of choice. Electrical testing in the
form of somatosensory evoked response (or potential)
testing may be ordered. This test measures how signals
are conducted through the spinal cord.
Cervical Stenosis / Cervical Myelopathy Treatment
In deciding how best to treat cervical stenosis/myelopathy
it is necessary to understand the natural history of
the problem. It has been said that in many cases, that
once the signs and symptoms of cervical myelopathy are
present that they may remain stable. Of course, they
may also progress and it is generally felt that decompression
has a better effect when signs and symptoms are mild.
Although the majority of patients will improve with
surgical decompression, a significant number will not
enjoy any benefit and a few may worsen.
There are two main approaches to surgical decompression
of cervical stenosis. Anterior (from the front) and
posterior (from the back). The anterior approach is
best for problems involving discs and bone spurs (which
are located in front of the spinal cord and not approachable
from the back). The number of levels to be treated is
decided by the surgeon. Anterior surgery will almost
always involve fusion with bone. In many cases, metal
plates and screws will be used.
The posterior approach will be considered when there
is generalized stenosis of the cervical spinal canal
or sometimes when there are three or more levels involved.
The surgeon will decide the specific operation. It is
important to note that when evidence of spinal cord
injury or atrophy is present, the outcome may not be
as good as when these problems are absent. This does
not mean that surgery should be avoided. Surgery may
help to prevent the problem from becoming more severe.
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