Spinal stenosis is a medical condition where the spinal canal narrows and compresses the spinal cord and nerves. This is usually due to the natural process of degenerative disc disease that occurs with aging. It can also sometimes be caused by spinal disc herniation or a tumour. Spinal stenosis may affect the cervical spine, the thoracic spine, the lumbar spine or all. Spinal stenosis can be broken into two categories, spinal canal stenosis or neuroforamenal stenosis. Spinal canal stenosis is usually asymptomatic until its final stages, whereas neuroforamenal stenosis results pain or numbness in the limbs. Loss of control of the limbs (pareses) requires surgery within weeks to prevent permenant damage.