Sciatica (or sciatica lumbo, common name for sciatic neuralgia) is pain depending on the territory of the spinal nerve S1 or L5 affected in the spine (lumbar spine) or in its immediate vicinity. It must be distinguished from the sciatic nerve, sometimes simply called "sciatica" and which arises from the meeting of several nerve roots (including L5 and S1). A lesion of the latter causes sciatica. Symptoms are localized to one side of the body. Pain may intensify with low temperature exposure.