The sciatic nerve is the largest nerve of human nervous system. Irritation of this nerve causes sciatic nerve pain. To diagnose sciatic nerve pain, doctors put more emphasis on physical examination of the patient and his/her past medical record. Location and nature of pain are also given importance during the initial phase of diagnosis. Sometimes, people who have survived from fatal accidents develop sciatic nerve pain too. Doctors also examine the patient regarding the possibility of Lumbar stenosis. This is defined as overgrowth or unrestricted growth of cells at vertebrae area. The overgrowth restricts the movement and growth of spinal cord.
 
Straight-leg-raising is one of the primary tests done to detect sciatic nerve pain. During this test, the patient is asked to raise his/her legs to various heights. By this, the doctor can figure out the exact location where the patient is experiencing pain. Rotation of hip can also help a lot to detect sciatic nerve pain. If the above tests do not detect the paining area, doctors go for magnetic resonance imaging (MRI).  CT scans are also immensely beneficial in this case.  Depending upon the nature and magnitude of pain doctors prescribe medication or surgery.