This is a video from Vox explaining what really happens when you pop your knuckles. It also details the findings of Donald Unger, a man who popped the knuckles on only his left hand for over 60 years to see if he'd develop arthritis. Did he? No. Does that mean you'll be fine cracking your knuckles your whole life and not run into any problems? MAYBE. What I do know is I've been cracking my penis for well over ten years now and it hasn't developed arthritis either. An inability to develop an erection, absolutely. Also now it kinda looks like a Z. I'm not gonna stop till it's a solid M. "Sick." Why, because I set goals for myself? "No, because your penis looks like an M.C. Escher drawing." I DREAM, AND I ACHIEVE.
Keep going for the video.
Thanks to Jessica E, who likes to crack her knuckles because it reminds her of the sound of enemy's bone's crunching. \oo/