Scoliosis is characterized by an abnormal spinal curve. When a person with a normal spine is viewed from the front or back, the spine appears to be straight. When a person with scoliosis is viewed from the front or back, the spine appears to be curved. Conditions known to cause spinal curvature include congenital abnormalities, neurological disorders and genetic. Approximately 2% to 3% of Americans at age 16 have scoliosis and it is more common in females.