Abstract

Spinal stenosis is the result of congenital or acquired narrowing of the spinal canal. It occurs most commonly at the L5 vertebral level, with women affected more commonly than men. Clinically, spinal stenosis usually manifests in a characteristic manner as pain and weakness in the legs when walking. This neurogenic pain is called pseudoclaudication or neurogenic claudication. These symptoms are usually accompanied by lower extremity pain emanating from the lumbar nerve roots. In addition, patients with spinal stenosis may experience numbness, weakness, and loss of reflexes. The causes of spinal stenosis include bulging or herniated disk, facet arthropathy, and thickening and buckling of the interlaminar ligaments. All these inciting factors tend to worsen with age. Patients suffering from spinal stenosis complain of calf and leg pain and fatigue when walking, standing, or lying supine. These symptoms disappear if they flex the lumbar spine or assume the sitting position. Frequently, patients suffering from spinal stenosis exhibit a simian posture, with a forward-flexed trunk and slightly bent knees when walking, to decrease the symptoms of pseudoclaudication. Extension of the spine may cause an increase in symptoms. Patients also complain of pain, numbness, tingling, and paresthesias in the distribution of the affected nerve root or roots. Weakness and lack of coordination in the affected extremity may be noted. Patients often have a positive stoop test for spinal stenosis. Muscle spasms and back pain, as well as pain referred to the trapezius and interscapular region, are common. Decreased sensation, weakness, and reflex changes are demonstrated on physical examination.