Ever since primeval man rose from all-fours to stand upright he's been suffering from back-ache. A sharp pain in the lumbar region of the spine.

Almost every human activity can bring it on: working at the kitchen sink, on a production line, driving a car, carrying a baby, or even just sitting down. But although we all get it, it's extraordinary how little we know about what causes it, or how to cure it. How dangerous, for example, is the domestic chair? How good are the osteopaths? What chance of a complete 'cure' for slipped discs?

Horizon reviews the situation and investigates some of the remarkable new spine research which one day may make everyone's life a little more comfortable.