Sciatica refers to pain that originates in the sciatic nerve, which is a large nerve that traces the lower back to the back of both legs. Causes of sciatica include degenerative disc disease, pregnancy, spondylolisthesis (slipping of vertebrae), irritation of the nerve roots in the lower spine and lumbar spinal stenosis (narrowing of the spinal canal).
Symptoms of sciatica include a burning in the legs, leg weakness, shooting pain, constant pain on one side of the butt and pain in the back of the leg or butt experienced while seated.