Sciatica refers to symptoms of leg pain—and possibly tingling, numbness, or weakness—that originate in the lower back and travel down through the buttock and the large sciatic nerve in the back of the leg.
Sciatica is often characterized by constant pain on only one side of the buttock or leg (it rarely can occur in both legs), pain that is worse when sitting, leg pain that is often described as burning, tingling or searing (vs. a dull ache), weakness, numbness or difficulty moving the leg or foot, or a sharp pain that may make it difficult to stand up or walk.