Time to talk about ribs.
Some of the most "Huh, that's interesting" or "Really?" moments I get as a chiropractor have to do with those 24, long, thin bones that wrap around your chest. When I tell people that part of the reason that they may be experiencing back pain is because of a rib being out of place, they usually have one of the reactions above.
Typically, when someone has a rib that's moved out of place, it presents as one sided pain in the mid and/or upper back that travels under the shoulder blade. Some people can get pain on both sides, pain along the side of the chest, chest pain on the front, and even pain that may feel like the beginning of a heart attack. Often times, it's a very painful ordeal because of all of the muscles attached to the ribs (actually the most pain I've been in was when I had some ribs out from changing our readerboard at work). In fact, between each pair of ribs, there are three muscles connecting the ribs that run in different directions. So, you can imagine that if a rib is being pulled back or pushed forward, it's going to place a lot of strain on those tiny muscles and the other muscles attached to the ribs.
The good news? Ribs that are out of alignment are fairly easily fixed by a chiropractic adjustment. Sometimes the ribs slide right back in place, sometimes it takes a little"coaxing". Most of the time, people get sore after having their ribs put back in place because of the strain on the muscles, but a little ice can work wonders with that.
So, if you're experiencing pain in your upper / mid back that goes underneath you shoulder blade, go have it looked at by a chiropractor. He/she should be able to do wonders for you.
Side Note: No, men do NOT have one less rib than women.