|
Lumbar spinal stenosis is a condition in which the spinal canal is
narrowed, causing the spinal cord or spinal nerve roots to be compressed.
Spinal stenosis is related to degeneration of the spine, as the facet
joints get larger and place pressure on the nerve roots. The condition
usually affects patients over the age of 60.
Approximately 75% of spinal stenosis cases affect the lumbar area of the
spine, and most will affect the sciatic nerve which runs along the back of
the leg. Standing upright further decreases the space available for the
nerve roots, and can block the outflow of blood from around the nerve.
Congested blood then irritates the nerve and the pain travels into the
legs.
Symptoms
The compression of lumbar spinal stenosis can produce the following
symptoms, which radiate into the buttocks and legs:
·
Pain
·
Tingling
·
Numbness
·
Weakness (rare)
These symptoms typically develop slowly over several years (although
they do occasionally come on suddenly), they are intermittent as opposed to
continuous, they occur during certain activities and in certain positions,
and they are relieved by rest or any flexed forward position. The most
common symptom of lumbar spinal stenosis is pain in the legs while walking,
which is relieved only by sitting and resting (not simply by stopping
walking).
The longer a patient with spinal stenosis stands or walks the worse the
leg pain will get. Flexing forward or sitting will open up the spinal canal
and relieve the leg pain and other symptoms, but they will recur when the
patient gets back into an upright posture. Numbness and tingling can
accompany the pain. Weakness is a rare symptom of spinal stenosis.
Diagnosis
The nerve compression of spinal stenosis will vary, depending on the
activity or position of the patient (standing, sitting, walking). Physical
examination alone will not be enough to correctly diagnose stenosis.
Either a Magnetic Resonance Imaging (MRI) scan or a Computed Tomography
(CT) scan with myelogram can be useful in diagnosing lumbar spinal
stenosis. Sometimes both are used. A non-enhanced CT scan (without
myelogram) is not useful in diagnosing this condition.
A spinal stenosis at two or even three levels can affect a single
emerging nerve. If surgery is considered, a combination of anatomical and
clinical examination is needed in order to make sure one surgical procedure
will address all contributing components of spinal stenosis.
|
