How does a disk become herniated?
As you grow older, the disks in your spine weaken and become flatter -- less cushiony. If a disk becomes too weak, the outer part may tear. The inside part of the disk then pushes through the tear and presses on the nerves beside it. The drawing to the right shows how a disk looks when it gets pushed through the tear and presses on a nerve. Herniated disks are most common in people in their 30s and 40s.
Written by familydoctor.org editorial staff