The Degenerative Spine
Answers for Spinal Stenosis:
Symptoms, Diagnosis and Treatment
We all know that the more miles you put on your car, the more likely
it is to begin having wear and tear problems. Our spines work in the same
way—like a car, the spine has important relationships among its moving parts.
The car can be traded for a new one but we must take care of our spine as best
we can for many years.
Spinal stenosis, often an end stage of the spine degenerative
process, is characterized by leg pain with walking. Pain will go away with rest
but you may have to specifically sit down to ease the leg pain. Occasionally
the symptoms of spinal stenosis will come on acutely, but most often it
generally develops over several years. A person who stands for long periods or
walks will worsen the leg pain. Bending forward or sitting will relieve the
pain because these positions help to open up the spinal canal, but the symptoms
recur if you stand straight again. Numbness and tingling can also affect you
while weakness is less common.
What is Spinal Stenosis?
Our lumbar spine (low back) and cervical spine (neck) are comprised
of multiple bones separated from each other by cushions (discs) and connected
to each other by small joints. Our anatomy allows our spine to protect
neurologic structures, absorb stress and weight, and position our body in
space. By its nature, as we age, we are more likely to have degenerative
changes that eventually can cause symptoms. Spinal Stenosis refers to narrowing
of the canal where the nerves travel to reach their ultimate destination (arms
or legs).
Our spinal canal is bordered by three important anatomic structures:
discs, joints (facet) and ligaments. With time, the discs dehydrate, lose their
height and can bulge, which can cause infringement upon the anterior portion of
the canal. At the same time, the small facet joints will begin to degenerate
and form bone spurs which can narrow the canal from the sides. Lastly, the
ligaments (ligamentum flava) that border the posterior portion of the canal can
hypertrophy and contribute to overall narrowing of the canal. The overall
degenerative process that contributes to spinal stenosis is slow and can take
many years to cause enough narrowing to produce symptoms.
Other Spinal Stenosis Symptoms
Typical patient complaints involve a loss of endurance and fatigue
associated with their lower extremities. Back pain often is associated with the
leg symptoms but is quickly alleviated when the patient sits. Common symptoms
that identify stenosis are decreased ability to walk distances, preference for
flexed positions (sitting and sleeping in a fetal position) or leaning over a
shopping cart. The body prefers a flexed spinal position because the canal is
at its widest dimension with bending rather than standing upright.
Diagnosis of Spinal Stenosis
Tests to confirm a diagnosis of spinal stenosis includes a MRI scan
or a CT scan with myelogram. These tests will confirm the suspected narrowing
and compression of nerve(s). Since spinal stenosis at one or two levels of the
spine can affect a single exiting nerve, a combination of imaging and a
physical examination by a spinal physician can confirm the diagnosis.
Non-Operative Treatment
Non-operative treatment refers to attempts to minimize the stenosis
symptoms without altering anatomy (surgery). Physical therapy is a mainstay
because increased strength & endurance of our trunk and neck muscles increases
support of the bony architecture of the spine and minimizes irritation of
degenerated anatomic parts. Non-steroidal anti-inflammatory drugs (NSAIDS)
contribute to pain relief by decreasing irritation but they do not change the
course of the disease process. Lastly, epidural steroid shots can decrease
swelling and irritation of pinched nerves to achieve pain relief. Conservative
measures work well because often significant relief can be obtained. In
essence, these non-operative measures buy time by minimizing symptoms without
altering the underlying issue of the aging spine.
Activity modification can be helpful. For endurance exercise, try a
stationary bicycle instead of walking since it is helpful to reduce pain by
bending forward. Additionally, leaning over a shopping cart or a walker is
effective and sitting in a recliner instead of a straight chair can be more
comfortable.
Surgery Treatment
The key to deciding whether or not to have surgery is the degree of
disabling pain or disability from spinal stenosis. When you can no longer walk
as you enjoyed before or care for yourself as you have previously, it may be
time to consider what surgery can do for you.
After a minimum of 6-12 weeks of conservative measures, if no
significant improvement has been obtained, surgery can be discussed. The
Laminectomy procedure involves “decompressing the pinched nerves” by removing
the posterior bony portion (lamina) of the narrowed canal. A laminectomy can
take from 1 to 3 hours depending on how many levels of the spine are involved.
There are minimal restrictions post-operatively. The majority of patients go
home the next day with no restrictions.
A decompressive laminectomy quickly relieves leg symptoms. Barring
any permanent nerve changes from chronic compression, patients quickly regain
lost strength and walking distance with the help of physical therapy. In
certain cases, stenosis is associated with spondylolisthesis, or slipped
vertebra. This “slip” can become worse after a laminectomy at the same level.
In cases like this, a spinal fusion during the same operation is added to
minimize potential back pain resulting from spine instability.
The risks associated with decompressive surgery are similar to most
surgical procedures. The biggest risk is associated with the anesthesia. To
reduce this risk, patients undergo a medical clearance by your primary care
physician or cardiologist prior to undergoing surgery. Other risks include
infection, dural tears (the nerve sack rips leaking spinal fluid, which is
repaired during surgery) and developing stenosis at other levels.
Surgical Expectations
Surgery results are generally 70-80% successful at 5 years. This
means you will be able to walk increased distances, have improved
functionality, less leg pain and less medication use. The main cause for
another surgery is if stenosis develops at levels above or below the primary
surgical site.
To conclude, spinal stenosis is a chronic degenerative process that
develops over many years. Conservative measures are available to control
symptoms until one feels his or her quality of life is severely inhibited. At
that point, surgery can be considered. Results from decompression are often
very rewarding, allowing the person affected by spinal stenosis to return to
their favorite activities.
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