This morning I learned that my father and I have something called perilunate instability.
My father sprained his wrist about two months ago, and it wasn't healing, which is why he went to the doctor and found out that he has this condition. Basically our wrists kind of pop when we twist them back and forth, though I'm not sure if that's perilunate instability, or whether it's not until there's some kind of stress or trauma to the wrist that it becomes a problem with a name.
I'm not particularly worried about the health of my wrists, though this may be a reason that they ache sometimes, and I should probably be more careful than I generally am. The thing is, I've always known that my wrists popped, but I thought everyone's wrists did that, so I didn't realize how abnormal this is. Apparently it's a very rare condition, which I guess has a certain cachet. If I'm going to have a physical abnormality, at least it's not plebian.