U is for Donald Unger

This is my contribution to ABC Wednesday and for Round Ten I am focusing on people from the past, some famous, others less so.
Donald L Unger

Donald L Unger

‘Mother, I know you can hear me. Mother, you were wrong! And now that I have your attention, can I stop eating my broccoli, please?’

Those are the words of Donald L Unger after he proved his mother wrong – that cracking your knuckles as a child does not cause arthritis in later life as she claimed.

Unger began his experiment as a child, cracking the knuckles of his left hand, but not his right, for over sixty years and demonstrated that this had no discernible adverse effect.

This dedication to the advancement of science earned the octogenarian physician the 2009 IgNobel Prize for Medicine.

However, you should be warned that knuckle-cracking isn’t without its dangers.  It can make your joints swell, inflame ligaments and may reduce the strength of your grip over time.

For the record, the popping sound you hear when knuckle-cracking isn’t that of something bursting, but of carbon dioxide bubbles forming in the synovial fluid contained in the membranes between joints.

Nobody’s prefect. If you find any spelling mistakes or other errors in this post, please let me know by highlighting the text and pressing Ctrl+Enter.

12 comments… Add yours
  • Roger Green 6th June 2012

    knuckle cracking is an important discovery!
    ROG, ABC Wednesday team

  • rhymeswithplague 6th June 2012

    Actually, I thought it was nitrogen bubbles.

  • Gattina 6th June 2012

    So far I have never done knuckle cracking ! Maybe I should try it out ?
    ABC Team

  • photowannabe 6th June 2012

    What an interesting thing to get a Nobel Prize for.
    I always heard it would cause problems with the knuckles too.
    Good post for U.

  • VioletSky 6th June 2012

    knuckle cracking is something that sets my teeth on edge!

  • luluberoo 6th June 2012

    My knee’s pop–does that count?

    ABC wednesday

  • Ann 6th June 2012

    Knuckle cracking can become a terrible habit!! Such a long experiment. I really thought it caused arthritis.

  • Reader Wil 6th June 2012

    I get goose pimples when I hear someone cracking knuckles. Thank you for this story!

  • Mr Parrot 6th June 2012

    Thanks to all for your comments. Photowannabe, please note that it was the IgNobel prize!

  • Leslie 6th June 2012

    My daughter does that all the time and it creeps me out. But I did know about the carbon dioxide thing so don’t worry about her getting arthritis – at least from that!

    abcw team

  • Meryl 7th June 2012

    What a cool post!!!! I just don’t like the cracking sound so I never tried to make it, but that it is carbon dioxide and not a joint popping…cool.

  • Carol Carson 7th June 2012

    It seems to me that swollen joints and ligament damage would be just as uncomfortable as arthritis. As a pianist, I maybe took more care of my hands than some, but admit, I always felt it better not to crack the knuckles. I love that Unger was curious enough to set up his own experiments. What a neat man. Thanks for the introduction.


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