Lumbar spinal stenosis can be caused by various disorders, both congenitally and secondarily. It results from hypertrophy or enlargement of bony structures, ligament, and other surrounding tissues and cause character- istic clinical symptoms and signs such as radiculopathy and intermittent neurogenic claudication. The pathophysiologic mechanisms known to be associated with these clinical symptoms and signs are arterial insufficiency, venous congestion, inflammatory response, biomechanical factors, and segmental spinal instability. The natural course of patients with lumbar spinal stenosis varies, but usually 15節30% of patients stabilizes over period or improves with conservative treatment, 30節45% become aggravated over the several years, and about 30節45% eventually requires some forms of surgery. However, there are no well known predictive factors how these patients progress over the time. Thus, appropriate treatment option and timing should be carefully decided according to the clinical settings. For this, treating physician should be aware of anatomy and pathophysiology of lumbar spinal stenosis with regards to various changes taking place in each individual. This review is to summarize the basic up-to-dated literature on pathophysiology of lumbar spinal stenosis in order to provide necessary knowledge required for the proper management of patients with lumbar spinal stenosis.
