I hurt my wrist while traveling. I went to the emergency room and had X-rays taken. The X-rays were normal, and no treatment was recommended. I took the X-rays home for my regular doctor to see. My doctor insisted on doing one more X-ray. Why was this necessary?

X-ray techniques are not always standard from place to place. It's possible that the X-ray technician used the wrong wrist position. Small differences in hand placement on the machine can make big differences in what the X-ray shows. Your doctor probably ordered one more X-ray in order to get the exact picture he or she needed.