Sciatica is when the sciatic nerve, the longest and widest single nerve in the body, becomes irritated or compressed. The pinched nerve can cause pain that radiates from your lower back down to your foot. Key Takeaways Definition: Sciatica occurs when the sciatic nerve, the body's longest and widest nerve, becomes irritated or compressed, causing pain from the lower back to the foot. Symptoms: Common symptoms include radiating pain, tingling, burning, numbness, weakness in the affected leg, and loss of bowel or bladder control. Risk Factors: Include age, obesity, occupation, prolonged sitting, and diabetes. Causes: Often caused by herniated discs, spinal stenosis, spondylolisthesis, back or spine pain, or piriformis syndrome. Treatment: Includes physical therapy, lifestyle changes, medications, steroid injections, and in severe cases, surgery.