Because of the many conditions which can compress nerve roots and cause sciatica, treatment and symptoms often differ from patient to patient. Diagnostic tests can come in the form of a series of exams a physician will perform. Patients will be asked to adopt numerous positions and actions such as squatting, walking on toes, bending forward and backward, rotating the spine, sitting, lying on back, and raising one leg at a time. Increased pain will occur during some of these activities.

Sciatica might be revealed by a neuromuscular examination of the legs by a physician. There may be weakness of knee bending or foot movement, or difficulty bending the foot inward or down. Reflexes may be abnormal, with weak or absent ankle jerk reflex. Pain down the leg can be reproduced by lifting the leg straight up off the examining table.