In several cases, sustained pressure on the fingertips during EVAs caused intense pain and led to the astronauts' nails detaching from their nailbeds, a condition called fingernail delamination.Astronauts' Fingernails Falling Off Due to Glove Design (via JWZ)
While this condition doesn't prevent astronauts from getting their work done, it can become a nuisance if the loose nails gets snagged inside the glove. Also, moisture inside the glove can lead to secondary bacterial or yeast infections in the exposed nailbeds, the study authors say.
If the nail falls off completely, it will eventually grow back, although it might be deformed.
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