What causes knuckles to crack? Scientists now think they know
by Nicola Davis from on (#3KE7C)
New model explains how pressure changes in joint fluid air bubbles create the noise
The sound of popping knuckles has long been a source of bafflement for scientists. Now researchers say they might have cracked its origins.
While previous research has shown that not all joints can make the sound, and that those that do can only be cracked once every 20 minutes or so, quite what is behind the auditory pop has been a topic of hot debate.