We have all seen (and heard) people cracking their knuckles. Some do it a lot. Does it cause arthritis?
The “pop” is caused by gas bubbles bursting in the fluid in the joint. The bubbles are caused by the pressure change in the joint due to the joint being stretched or pulled.
The verdict based on most studies is that there was no increase in arthritis for those who crack their knuckles, but possibly much bigger and longer term studies need to be done. It is possible to damage things in and around the joint and possibly hypermobility (too much movement, too loose) can occur in the joint, if cracking is done frequently and repetitively.