DOC'S ADVICE: don't ignore your body when it's telling you stuff.
I took a bad fall on a MTB in December of 2006, and spent 3 months nursing a very sore shoulder. Of course it didn't keep me off the bike--do I look like a whiner? As any self-respecting doctor would do, I grabbed my orthopedic buddy for a curb-side consult in between surgical cases. He said it didn't look too bad, probably just a bursitis. So then I did what any self-respecting bike racer would do: I ignored the pain and loss of range-of-motion, and kept riding.
I fell a couple more times (all on MTBs) over the past 14 months, including my Chequamegon crash. Most of these were to the left, landing me on the bad shoulder all but once (whereupon I injured my right shoulder, but not badly--at least not so far). None of these crashes hurt for more than a week, and the shoulder went back to its baseline (funny cracks and clunks when I put on a suit jacket, pain when I sleep on it, and the occasional seizing up where it feels like someone stabbed it with a dull blade).
Yesterday, I was minding my own business, finishing the Lord of the Rings extended edition while on the trainer. 2 hours Friday night, and 5 hours each Saturday and Sunday. Everything went like clockwork (OK, a very slow clock since trainer time is different than regular time), and the only thing that hurt afterward was my butt. This despite our new GrandStay kit with the new and improved diaper (it really is better than last year's).
I took off my jersey and turned on the shower, glancing at my left arm in the process (no, I do not flex in front of the mirror, at least not very often). Dang it if I didn't have a hollow where my left bicep should be, and a bulge just above the elbow where it shouldn't be. I realize that my pipes aren't particularly buff, even at their best, but this was freaky. I got that nauseated feeling like you get when they keep showing the NFL lineman's leg bending 90 degrees where it shouldn't.
Apparently, rupturing your bicep long tendon (which I've done) is often related to having previously sustained a rotator cuff injury or shoulder separation (which I didn't know I had but maybe should have known). So, I'm off to the MRI machine in 10 minutes to find out what I should have gotten checked out last winter. Videos at 11.