Slipped disc. Coloured 3-dimensional computed tom- ography scan of a slipped disc (red, lower centre) pressing against the spinal cord (dark blue). The spine bones (light blue) have been cut open" by computerised image manipulation techniques. The red discs between the spine bones are small shock absorbers that cushion movement while keeping the spine flexible. Slipped disc occurs when the outer layer of one of the discs weakens or ruptures, allowing the pulpy contents to bulge out and press against the spinal cord or one of its nerve branches. Pain and numbness are typical symptoms. In rare cases damage to the spinal cord can cause partial paralysis."