Disks are the rubbery pads that provide cushioning between vertebra. Also known as a "slipped" disk, a herniated disk occurs when part of the disk pushes past the edge of the vertebra, and puts pressure on the spinal nerves.
Depending on the location of the nerve pressure, herniated disks can cause pain, numbness, or weakness in the neck, back, arms, and/or legs. In the lower back, the most common symptom is sciatica — a sharp pain that extends from the lower back down the back of one leg.
Most cases of herniated disk can be treated non-surgically with rest, pain medication, and/or muscle relaxers. Severe cases may require surgery to remove all or part of the disk.