Chiropractic is based upon manually restoring joint motion to improve function of the musculo-skeletal and nervous systems. As a simple illustration, consider what happens to an arm or leg put into a cast after a bone fracture. The arm or leg shrivels and wastes away (atrophies) because motion of the elbow or knee joint is restricted. When the cast is removed, joint motion is restored and the limb comes back to life. Similarly, chiropractic adjustments restore motion to joints in the spine and have a dramatic effect on the health of the surrounding tissues. Included in the surrounding tissues are the nerve roots of the spinal nerves that link the brain to the rest of the body. Because these spinal nerves are the conduit over which the brain controls the function of every cell in the body, it is imperative to the health of every cell in the body that the spinal nerves be healthy. That is why the joints of the spine need to be adjusted – to keep them moving fully and freely. Chiropractors are the only doctors trained to diagnose and treat bio-mechanical dysfunction of the spinal joints by means of an adjustment.