It has become a legal problem, mainly because of the way the court system works. Malpractice has changed the ways physicians' practice. In some areas the physician has to order more tests. It's mainly to rule out a fracture. If he misses the fracture in his examine and doesn't find it through a x-ray, he will be liable for damages.
Many physicians order extra tests just to cover themselves against malpractice.
I would guess that twenty percent of health care dollars are wasted on unneeded tests.