popping joints (NOT a drug question)

When I was maybe ten or eleven, my thumb got stuck in the car door,meaning I slammed the door on my left thumb. It was jammed.

Ever since, my left thumb has had to pop about once every minute. Could the door accident have made a cappillary get pushed over so the oxygen is going to the joint, causing the frequent pops? Or is there some other explanation?

There is some other explanation.

Well then what is it?
Isn’t that the purpose of GQ? To provide answers?

Blood vessels, and thus capillaries, do not randomly spew oxygen like a garden hose spews water. If a capillary was displaced (“pushed over”) it wouldn’t suddenly start oxygenating a part of the body it never had before. Thus I doubt your joint popping is due to oxygen (or any dissolved blood gas) accumulating around the joint.

My vote is some structural damage was done to the joint. In fact, the sound you hear might not even be the same thing as “cracking your knuckles” (I suspect it isn’t).

Ever had it x-rayed?

Well I have an anecdote,
I messed up my elbow (2 fractured bones, dislocation, and a good deal of soft tissue damage) about 8 months ago and mine pops every so often, espicially after push ups. Coincidentally I also messed up my wrist in the same incident (apparently I had a very interesting injury) and now I can make it click.

I’ve heard medics say that the cause of the popping sound is due to the presence of nitrogen in the joint capsule. Whether this actually causes the sound, called crepitus, is beyond my knowledge.