I have SFN and found this bit of news interesting. I have had dull, aching pain around the bottom of my rib cage when I have been in an upright position too long. A heating pad and being in my recliner are helpful. I also have celiac disease which, along with SFN, can cause SOB. My cardiologist kept saying my SOB was not heart related but no one could give me another explanation. I had a lung study done and I came out fine. Another dx I have is median arcuate ligament syndrome which plays games with my diaphragm and possibly rib cage.