A disc herniation is a rupture of the disc material between the bones of the spine (vertebra). A spinal disc is a pad that serves as a cushion between each vertebra. Discs are designed like jelly donuts, with a softer center encased within a tougher exterior. A herniated disc, sometimes called a slipped or ruptured disc, occurs when some of the softer “jelly” pushes out through a crack in the tougher exterior.

A herniated disc can irritate adjacent spinal nerves and result in back pain, leg pain, numbness or weakness in the leg. On the other hand, many people experience no symptoms from a herniated disc. Most people who have a herniated disc don’t need surgery to correct the problem. The vast majority of disc herniations will occur toward the bottom of the spine at L4- L5 or L5- S1 levels. In addition to typical sciatica symptoms, nerve impingement at these levels can lead to:

• L5 nerve impingement (at the L4 – L5 level) from a herniated disc can cause weakness in extending the big toe and potentially in the ankle (foot drop). Numbness and pain can be felt on top of the foot, and the pain may also radiate into the buttock.
• S1 nerve impingement (at the L5 – S1 level) from a herniated disc may cause loss of the ankle reflex and/or weakness in ankle push off (patients cannot do toe rises). Numbness and pain can radiate down to the sole or outside of the foot