The back includes the bones of the spine ( vertebrae that
support body weight), their joints, the
discs that separate the vertebrae and absorb shock as you move, and the muscles
and ligaments that hold it all together.
Back pain occurs when one or more of these structures is injured. Back pain can also occur when you
sprain or strain the ligaments or muscles from a sudden or improper movement or
due to overuse. If you damage your discs so that they tear or stretch and the
tear is large enough, the disc may press against a nerve, the irritated nerve
may swell or become inflamed thereby causing back pain.