Will cracking my knuckles give me arthritis?

This post has been updated. It was originally published on October 9, 2018.

When he was a child, Donald Unger’s mother and aunts warned that he shouldn’t crack his knuckles, because he would develop arthritis. To prove them wrong, he set out on a half-century long experiment, cracking the knuckles on his left hand at least twice a day, while leaving the right knuckles (mostly) uncracked.

After 50 years, Unger (then a doctor in Thousand Oaks, California) examined his hands—and found no evidence of arthritis in either one, and no other differences between them, either….