Is disc protrusion the same as disc herniation?

Answer 1

No... but close... Let me explain what discs are, and what they do... Looking down on the involved levels, the top is toward your abdomen (NOON) and the back is toward the back (6 O'clock). I'll describe what happens, referring to times on the clock. The disk consists of two parts… the outer ring (annulus) and a very thick gel (nucleus pulposis) in the center. Over the years the discs gradually wear & become weak and begin to bulge outward (like squashing a marshmallow). If the outer ring tears then the thick gel center extrudes, it is then called a herniation. If the herniation occurs at 5 o'clock or 7 o'clock, the herniation can pinch (trap) a nerve as it is preparing to leave the spinal cord and travel down the body, resulting in severe burning pain and possibly muscle cramps if the nerve travels to the spasming muscle. If the herniation occurs at the NOON, 3 o'clock, or 9 o'clock position, since no nerves are close by, there is no pain (actually, there can be pain, but it is not from nerves being pinched... there are pain fibers in the annulus of the disk). If the herniation occurs at the 6 o'clock position no nerves will be trapped or pinched because there is a lot of space (relatively speaking) in the spinal canal where the spinal cord travels. So a disc 'bulge' is just where the disk is squashed out a little toward the left. You can have some pain from that, but no spinal nerve involvement. Copy & paste the following into your browser to see images of what I'm talking about: http://www.espalda.org/english/divulgativa/dolor/causas/alteraciones/fisura.asp

Answer 2

Bulge, herniation, protrusion. Terminology varies but a bulge generally protrudes less. A herniation or protrusion sticks out more when looking at an MRI.