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.
The compression of lumbar spinal stenosis can produce the following symptoms, which radiate into the buttocks and legs:
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.
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. Come to our pain clinic today for an examination.