If the sciatic nerve is injured or becomes inflamed, it causes symptoms called sciatica. Sciatica can cause intense pain along any part of the sciatica nerve pathway – from the buttocks to the toes. If the nerve is compressed, caused by conditions such as a bulging or herniated disc or tumor (rare), symptoms may include a loss of reflexes, weakness and numbness besides severe pain. Sciatic nerve pain can make everyday activities such as walking, sitting and standing difficult.