article_snippet.sent: One of Their study's co-authors, chiropractor Jerome Fryer, was used as the guinea pig for Their study and lent his own knuckles to the cause.
article_snippet.sent: But Greg Kawchuk, a professor of rehabilitation medicine, who led the study published scientific journal PLOS ONE, noted that some studies suggest some studies does no harm.
article_snippet.sent: Greg Kawchuk, a professor of rehabilitation medicine, who led the study said:
highlights_snippet.sent: A study co-author was used as the guinea pig for the experiment .
  