If 2010 was the year you were going to stop cracking your knuckles, you may want to consider another resolution.
Despite what such renowned authorities as your mother might say, the obnoxious habit does not lead to arthritis of the fingers, according to several studies, including one by California doctor Donald Unger, who was recently recognized for his hands-on research of the topic.
For 50 years, Unger popped the knuckles of his left hand at least twice a day, leaving his right hand as a control. "Thus, the knuckles on the left were cracked at least 36,500 times, while those on the right cracked rarely and spontaneously," he wrote in a letter to the editor in the journal Arthritis & Rheumatism in 1998.
Unger's data set showed no arthritis in either hand and no apparent differences between the two hands, a finding that earned him the 2009 Ig Nobel Prize in Medicine, a Nobel Prize parody that is awarded to research projects that "first make you laugh, then make you think."
Unger conceded that a larger group would be necessary to confirm his findings but that the results call into question whether other parental beliefs, such as the importance of eating spinach, are also flawed. "Further investigation is likely warranted," he wrote in his 1998 report.