Sciatica refers to severe pain caused by various reasons that result in the compression and irritation of the sciatic nerve. The typical pain of sciatica radiates from the lower back to the buttock or the back of the thigh and the lateral side of the leg down to the foot. The pain can intensify during coughing or increased abdominal pressure. Additionally, this condition is often accompanied by dullness or numbness, and in a minority of cases, it can cause bilateral sciatica. Generally, there are three main causes of sciatica: The first is chemical irritation, mainly when the disc tissue comes into contact with the sciatic nerve, releasing chemical substances that stimulate and trigger an autoimmune response, resulting in neuritis. The second cause is mechanical compression, primarily from protuberance and nucleus pulposus compression or traction on the already inflamed nerve root, leading to obstructed blood flow and worsening edema. The third cause follows chemical stimulation and mechanical compression, leading to ischemic symptoms in the injured nerve, which then results in pain. Therefore, sciatica typically has primary and secondary causes. The primary cause is sciatic neuritis, while secondary causes are usually associated with lumbar spinal stenosis, lumbar disc herniation, lumbar tumors, and piriformis outlet syndrome.