Einar Wilder-Smith, a neurologist at the Luzerner Kantonsspital, discovered that fingertips wrinkle in water due to vasoconstriction.
Aina Wilder-Smith
Why do fingers curl in water is an age-old question every child asks when taking a bath, but the answer may be unexpected. “It means a lot not to have wrinkles all over your body,” he said. Aina Wilder-SmithNeurologist at Luzerner Kantonspital. Unlike the surrounding skin, the outermost layer of the fingertip is highly innervated and connected to the vascular system, setting the stage for the development of fleshy fingers.
While osmosis, especially into dead skin cells, seems like a compelling explanation for this strange phenomenon, “the opposite is actually true,” says Wilder-Smith.
In the early 2000s, while working at the National University Hospital of Singapore, Wilder-Smith suspected that the surrounding vascular system was causing wrinkles. He discovered that when you soak for a long time, blood vessels settle just beneath the skin. tightenThis results in the outermost layer of the skin being pulled down due to negative pressure.1 Uneven wrinkle patterns can be caused by varying levels of skin tightness, or binding, across the fingertips.
Why do my fingertips wrinkle?
Wilder-Smith doesn’t exactly understand how water causes blood vessels to constrict. theory.1 “There is a whole array of different electrolyte channels, and it is likely that these channels are selectively stimulated,” he said.
Observational studies in patients with peripheral nerve injury further support the notion that wrinkling is an active process. The median nerve runs from the arm to the hand and regulates sweat and blood flow. Patients with hand nerve damage do not show symptoms wrinkles on the affected finger.2 In the 1970s, the mother of a child who had suffered nerve damage to her hand noticed that her fingers had shriveled again after nerve repair. This observation inspired Seamus O’Riain, a hand surgeon at University College, to simple test It is still used today as a method of reading nerve function using wet fingertip creases.3
FAQ
Why do my fingers cut off when they get wet?
• Immersion in water constricts blood vessels under the skin. In the case of wrinkled fingertips, this is controlled by messages from the median nerve, which runs from the arm to the hand to regulate sweating and blood flow. Negative pressure caused by vasoconstriction pulls the outermost layer of skin downward into an uneven pattern of wrinkles. This may be because the skin is tight or the entire fingertip is tied.
Why do fingertips wrinkle on dry hands?
• Dry, wrinkled fingertips may be associated with a variety of health conditions associated with poor circulation, including dehydration and Raynaud’s disease.
This article was originally published on November 1, 2023. Updated on January 11, 2025 by . Deanna McNeil, Ph.D..
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