Good evening Beth,
Well, theoretically it is possible that your aunt broke her rib because she sounds so frail plus has osteoporosis but, of course, the only way of knowing for sure is to do an x-ray.
Now, do I think it is necessary to do an x-ray? The answer is no, I dont think she really needs to have it done because even if there is a broken rib vs. sprained cartilage vs. pulled muscle (these are additional possibilities), the treatment would be the same and includes pain management with pain medications.
Certain symptoms can kind of give you an idea if there is a broken rib such as if she has more pain when she coughs or sneezes or turns. She would probably moan with pain while attempting to turn or after sneezing/coughing. But again, there is no special treatment for a cracked rib. If you do notice that she is in more pain, call her doctor and ask for some pain medications. Also, try putting a pillow under her arm, kind of around her ribcage. This will minimize how much her chest wall moves and will help with pain during movements.
Please let me know if you have other questions. I will be on the computer for a bit longer and then again tomorrow.
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