The sciatic nerve is the largest nerve in the human body, running from the lower back down through the hips and buttocks, and extending into each leg. It is formed by the nerve roots that emerge from the spinal cord in the lower back, specifically from the lumbar and sacral regions. This nerve is responsible for providing sensation and movement to the legs and feet. When the sciatic nerve becomes compressed or irritated, it can lead to a condition known as sciatica, which is characterized by pain, tingling, or numbness that radiates along the nerve's path. Common causes of sciatica include herniated discs, spinal stenosis, and muscle spasms. Treatment options often include physical therapy, medication, and in some cases, surgery.