How does a disk become herniated?

Wear and tear: Unless there is a severe trauma, discs become herniated as the wear and tear of daily living builds up. The outer ligament of the disc, the annulus fibrosis, develops tears that ultimately allow some of the inner material, the nucleus pulposus, to push through and put pressure on the nearby spinal nerves.

Disc: Most commonly from a sudden increase in intra-abdominal pressure. This can occur with sneezing, coughing, straining, etc.