Brief Answer:
Blunt trauma

Detailed Answer:
Hello

Thanks for the query

It looks like you have been investigated in depth by the cardiologist however the pain could be arising from the ribs, lungs or the pleura. I would like to add here that chronic pain due to blunt trauma is common and tends to last for several years. Here is how you should go about it

1. Get a CT chest with contrast to rule out minor trauma to the ribs and also see for any injuries to the lung
2. Get a second opinion from an orthopedic surgeon to look for costo chondritis
3. Send for total CPK to look for muscle injury
4. If nothing comes up then I would recommend you to get XXXXXXX done to look for vascuitis, vasculitis can also present the same way

I hope I was of help, if you have any further queries please get back to me

Regards

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