While vigorous or improper flossing may cause bleeding, swollen gums and other minor nuisances, one Wisconsin woman has flossing to blame for an unlikely health problem — her knee infection.
The 65 year-old-woman's case was published in the BMJ Case Reports journal in August, and details the process by which doctors came to discover that the woman's sudden knee pain and swelling likely originated from a new flossing routine she took up — a vigorous one at that.
With chills, pain and swelling in her knee, the woman arrived at a hospital emergency room for help, reports Live Science. When doctors took a fluids sample from the affected area, they were taken aback by their findings.
Doctors discovered that the pain and swelling was due to a bacterium, Streptococcus gordonii. While her symptoms were in line with most bacterial infections, the location of the bacterium itself was not.
"This bacteria lives in the mouth, (but doctors) happened to find it in a place where we don't typically find it, which is the knee joint," the report's co-author and infectious diseases doctor Dr. Ala Dababneh said.
The woman admitted to the doctors she had recently taken up a "vigorous dental flossing regimen" that frequently led to bleeding gums.
After undergoing surgery to remove as much of the bacteria from her knee cap, which was a replacement from a surgery done five years before, she was able to keep her knee, but must continue taking antibiotics.
While a real medical problem that was quickly acted on, Dabaneh strayed from discouraging people from flossing for fear of developing knee infections.
"It's a rare event. I don't want people to worry that just flossing is going to cause than an infection in their prosthetic joint," he said.
Roughly 1 in 100 patients who have undergone knee replacement may develop an infection after the operation, according to the American Academy of Orthopaedic Surgeons.