Sciatica is not a disease but a symptom. Sciatica is pain arising in the sciatic nerve, most often from something irritating it not trapping it.
The sciatic nerve is the largest nerve in the body, running from the spinal cord down through the buttock and the back of each leg to supply all the muscles of the lower limb. It also carries sensory information back from the leg to the cord, and via the cord to the brain.
Last updated: 11 November 2011
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