The fact is that four out of five Americans will have some sort of spine-related pain at some point in their lives. Neck and back pain may be the most universal physical complaint in the United States today, affecting men and women with equal intensity, regardless of income levels or occupational considerations, from factory workers to corporate executives, from active young parents to aging weekend athletes. Spine disorders rank only behind arthritis and heart disease as a cause of working-years disability.

It's easy to see why. The human spine is a complex assemblage of parts: bony vertebrae stacked atop each other, connected by hinging joints, separated by shock-absorbing discs, held together by muscles and tendons, and surrounding the delicate spinal cord that carries the body's central nervous system.

The spine plays an essential role in almost everything we do, from sleeping to carrying our kids, from sitting at a desk to swinging a golf club. Although it's a symbol of strength (look at the meaning of the word "backbone"). The spine is exceptionally vulnerable and we don't care for it very well. We take it for granted in our everyday lives, letting it languish unexercised and unchallenged, until we suddenly call upon it to help us shovel snow or move a piano. Then we find that it lets us down. And out.