Everyone's spine has natural curves. These curves round our shoulders and make the lower back curve slightly inward. But some people have spines that also curve from side to side, a common condition called scoliosis. On an X-ray, a spine with scoliosis looks more like an "S" or a "C" than a straight line. Some of the bones in a scoliotic spine also may have rotated slightly, making the person's waist or shoulders appear uneven.
Scoliosis affects about 2 percent of the population, including children and adults, and tends to run in families. If someone in a family has scoliosis, the likelihood of another family member having it is much higher — about 20 percent.
As the population ages, adult degenerative scoliosis is becoming more common, with the condition typically developing at between age 50 to 70. The condition can have devastating effects on a person's life in later years. Treatment in this older population presents particular changels due to other back conditions, such as osteoporosis. But significant advances — including minimally invasive surgery, new neuro-monitoring techniques and 3-dimensional imaging — allows older patients to receive limited doses of anesthesia and benefit from quicker recovery.
Scoliosis is defined as curvature of the spine greater than 10 degrees, as measured on an X-ray. Anything less is simply due to normal variation.