Friday, November 28, 2014
Spine and Back Health
Could you please explain the symptoms of neurogenic claudication in the legs that is caused by arthritis in the spine? Can the spinal cord or nerve roots be compressed anywhere at any location in the spine? Can this occur in the thoracic, cervical or sacral area? What are the symptoms at the actual nerve or cord compression site? (Would there be stiffness and tightness, but not actual pain?) Thank you.
Thank you for your question. Neurogenic claudication is not typically associated with compression of the spinal cord, but of the nerve roots in the lumbar spinal canal. Therefore it is primarily associated with lumbar spine disease.
The most common cause is a cascade of events in which the intervertebral disc and facet joints both begin to wear out (doesn't really matter which one starts first, because once one of them starts to wear out the other usually does too).
This is a gradual process that usually takes years, which is why the problem is much more common in older people. As the disc wears out it begins to bulge, causing narrowing of the spinal canal. As the facet joints develop arthritis they hypertrophy (fancy word for getting bigger), causing more narrowing of the spinal canal.
Finally, a ligament called the ligamentum flavum begins to hypertrophy (thicken), taking up even more room in the spinal canal. The combined narrowing of the spinal canal causes pressure on the nerve roots as they traverse the area of narrowing - this is why the symptoms can be more vague, and more difficult to localize, than a simple herniated disc, which typically affects a single nerve root only.
The pressure on the nerves begins to choke off the blood supply to the nerve, causing the nerve to temporarily malfunction, which causes the symptoms of pain, numbness, tingling, and/or weakness.
Since the symptoms depend on the degree of narrowing of the canal, which is worse when standing or walking, the symptoms tend to occur with these two activities, and tend to go away when sitting or lying down. Any symptoms in the area of the spine itself, such as stiffness or tightness, would be caused by the underlying arthritis in the spine or muscle spasms, not by the spinal canal narrowing (=stenosis) itself, and would not be considered part of "neurogenic claudication".
I hope this answers your questions. Take care, and stay well.
David J Hart, MD
Associate Professor of Neurosurgery
School of Medicine
Case Western Reserve University