Typically occurring on one side of the body, sciatica usually begins with a herniated disc in the lower spine, also known as the lumbar spine. It refers to the compression of the body’s longest nerve, which runs from the base of the spine down both legs. The pressure on the nerve, most commonly caused by disc herniation or bone spurs, leads to pain in the lower back. This pain may spread to the buttocks, legs, and feet and it may also cause numbness, a tingling or burning sensation, and muscle weakness. The pain may become worse when attempting to sit or when coughing and sneezing.