Recently, Canadian researchers decided to find out once and for all what causes the sound when people crack their knuckles. In a study called Real-Time Visualization of Joint Cavitation, they aimed to challenge the long-held assumption of many that sounds emitted during knuckle cracking were from the collapse of a bubble formed in synovial fluid when the bones of the joint separated. Yet from the result of the MRI the scientists were able to determine that “the mechanism of joint cracking is related to cavity formation rather than bubble collapse.” There you have it. Another medical mystery put to rest.
via Neatorama
