When doing a CXR, the pt generally has to stand with chest up against the board. The person performing the xray has to be able to see your spine so they can properly align the crossbar of the light to you. Otherwise, they may not be able to get all of your ribs, lungs onto the xray. Is it your ribs that are sore or the intercostal spaces (area between ribs). If it's the area between ribs, and are sick with cough, you might have pleurisy. Did you get injured?? They might be looking for a cracked rib, which they really can't do much for other than prescribe pain meds. Cooperate with xray person, they are professionals, it's makes their and your life easier, besides, you don't want to have to do more xrays than necessary. Tell them your bra has absolutely no metal and they might let you wear the bra but still want you to wear a gown or paper shirt opened in back so they can see your spine. Metal not good with xray because it pulls more radiation to that area.