pod,
a few years ago, i had wierd rib pain in both the center of my chest at sternum as well as to the left.
it got so bad at one point, i thought i was having a heart attack! i drove to the hospital and had an ekg. it was fine.
i went through xrays, mri's, bone scans. no one could find a damn thing. this went on for months and i was gobbling ibuprofen like candy.
i finally found a chiropractor who was able to knock the rib back in place. i am a big guy and it took a big man to be able to do this.
i had to continue this treatment for 6 months before it started to go away.
to this day, it flares up, but i can generally get my wife to stomp on my back and fix it up. i also ordered a special device that is used to pop the rib in place. it's called an activator i believe.
long story short: rib injuries are very difficult to diagnose. the medical term for my condition is costochondritis (inflammation of the chest wall)....
you may want to get a chiropractor but be careful, because a lot of them are quacks.