Many people have evidence of spinal stenosis on X-rays, but have no signs or symptoms. When symptoms do occur, they often start gradually and worsen over time. Symptoms vary, depending on the location of the stenosis:
In the neck. Narrowing in the upper (cervical) spine can cause numbness, weakness or tingling in a leg, foot, arm or hand. In severe cases, nerves to the bladder or bowel may be affected, leading to incontinence.
In the lower back. Compressed nerves in your lower (lumbar) spine can cause pain or cramping in your legs when you stand for long periods of time or when you walk. The discomfort usually eases when you bend forward or sit down.
Source : Mayoclinic.org