I was changing a tire the other night when I felt the familiar double-click of shoulder leaving its socket and going back in. Cue searing pain, and now I can look forward to a week of fitful sleep, interrupted by that same pain every time I roll over.
The shoulder is the bane of old bikers, especially old mountain bikers (and trust me, in mountain biking, 40 is old). if you frequent a bike shop and haven't seen at least one of its employees in a sling at some point over the years, shop elsewhere, because it's likely those guys don't ride.
I've come to expect the double-click from my right shoulder. I crashed on it while commuting back in 1992, misjudging a curb hop, going over the bars, and landing full-force on my right elbow. Quick ER trip, six weeks in a sling, and it hasn't been right since, giving me an old-farmer-on-the-porch ache whenever the weather's changing. When the arthritis that plagues my family finally finds me, I know its point of entry will be that old dislocation.
The left is one of those sneaky old injuries, though. Same basic story: 1994, riding trails near Iowa City, bottom of a long, fast descent, carried too much speed into the corner, went flailing off into the woods, bike went out from under me, I hit the ground rolling (textbook technique!) in an absolutely spectacular "cloud of dust" yard-sale crash, and I came up with a bum wing. That one popped back in almost immediately, and -- thanks to the rush of endorphins -- convinced me that while my day on the trails was over, no trip to the ER was necessary. I skipped the sling time without incident, and Its been pretty much dormant and forgotten ever since... until the other night.
The thing about shoulders is that once you've hit them with enough force to temporarily disassemble them, they'll come apart with remarkable ease after that. They will -- literally! -- pop out if you sneeze on them. I once saw a mechanic do just that... he happened to be leaning on the workstand at just the right angle, sneezed, and popped a shoulder. My pop the other night came as I was levering a particularly tight tire bead onto a rim... my shoulder wasn't even involved, but the angle and force must have been exactly right. I'm sure that given the right circumstances, you could literally pop one out at the drop of a hat, but I'd rather not prove the adage.
Someday, I suppose I'll want to have these things surgically repaired. For now, though, the occasional downtime is just a nice memory trigger to the days when I was younger, stupider, and much more durable.