Do you know what spinal stenosis is in the lower back?

In general, 3: Central stenosis, lateral recess stenosis, or foraminal stenosis.

Not enough space...: Each bone in the spine has a space that contains the nerves. The space can get too narrow for the nerves to function normally. This is spinal stenosis. Most spinal stenosis is caused by degenerative disease: disc bulges, bone spurs from the facet joints, thickening of the ligaments. Symptoms can include leg pain, heaviness, tingling, etc, usually worse with standing or walking.

Spinal Stenosis: Narrowing of the spinal canal usually due to arthritis, herniated discs or congenital.