A herniated disc is one of the most common reasons people see a spine specialist. It is also called a slipped disc or a ruptured disc.
Each spinal disc is like a jelly donut, with a soft center (nucleus) surrounded by a tough outer shell (capsule). If you have a herniated disc, the capsule cracks or breaks and the nucleus squeezes through the opening. This can irritate the spinal cord or nearby nerves and cause weakness and numbness in the arms or legs. A severely herniated disc can cause paralysis (inability to move your arms or legs).
A herniated disc can occur anywhere in the spine but is most commonly found in the lower back (lumbar spine) and neck (cervical spine).