Sciatica Sciatica is distracting pain that may be caused by general compression and/or irritation of one of five nerve roots in the low back that give rise to the sciatic nerve, or by compression or irritation of the sciatic nerve itself. The pain is felt in the lower back, buttock, and/or various parts of the leg and foot. In addition to pain, which is sometimes severe, there may be numbness, muscular weakness, and difficulty in moving or controlling the leg. Typically, the symptoms are only felt on one side of the body. Although the pain appears to be in the leg, the culprit is often in the lower back!