Animation showing herniation of the intervertebral discs, a condition commonly called a slipped disc. This occurs when the walls of the intervertebral discs (grey) weaken and can rupture, allowing the pulpy central tissue to bulge through the wall. This results in projections (red), which can compress adjacent nerves, causing pain, muscle weakness, numbness and tingling. Treatment includes anti-inflammatory drugs, physiotherapy and, as a last resort, surgery.