May 15, 2024

Why Do Fingers Prune?

Scientists still do not understand how precisely water triggers vasoconstriction, although Wilder-Smith has his theories.1 “Its likely that theres a whole variety of various electrolyte channels, and that these are selectively being stimulated,” he said.Observational research studies in clients with peripheral nerve damage further support the idea that wrinkling is an active process. The typical nerve runs down the arm into the hand and regulates sweating and blood flow. Patients with nerve damage in their hands did not display wrinkling in the affected fingers.2 In the 1970s, the mother of a child with nerve damage in the hand observed the return of shriveling fingers following nerve repair.

Einar Wilder-Smith, a neurologist at Luzerner Kantonsspital, found that vasoconstriction triggers fingertips to wrinkle in water.Einar Wilder-SmithWhy fingers shrivel up in water is an age-old question that every child asks at bath time, but the response might come as a surprise. “The whole body doesnt wrinkle, and that states a lot,” said Einar Wilder-Smith, a neurologist at Luzerner Kantonsspital. Unlike the surrounding skin, the outer layer of the fingertip is extremely innervated with and connected to vasculature, setting the phase for pruney fingers. While osmosis, particularly into dead skin cells, looks like a compelling description for this curious phenomenon, Wilder-Smith clarified, “In reality, its the opposite.” In the early 2000s, while operating at the National University Hospital in Singapore, Wilder-Smith presumed that the surrounding vasculature drives the wrinkling. He found that after a long soak, capillary nestled just below the skin constrict, leading to negative pressure and downward yanking of the outermost layer of skin. The uneven puckering pattern most likely outcomes from different skin tautness, or tethering, throughout the fingertip. Researchers still do not understand how precisely water sets off vasoconstriction, although Wilder-Smith has his theories.1 “Its most likely that theres an entire selection of various electrolyte channels, and that these are selectively being promoted,” he said.Observational research studies in clients with peripheral nerve damage even more support the idea that wrinkling is an active process. The median nerve diminishes the arm into the hand and regulates sweating and blood flow. Clients with nerve damage in their hands did not show wrinkling in the afflicted fingers.2 In the 1970s, the mom of a child with nerve damage in the hand saw the return of shriveling fingers following nerve repair work. This observation inspired the hand surgeon Seamus ORiain at University College to develop a basic test that utilizes wet fingertip wrinkling as a readout of nerve function, which is still utilized today.3 ReferencesWilder-Smith E, Chow A. Muscle Nerve. 2003; 27( 3 ):307 -311. Wilder-Smith E. Clin Auton Res. 2004; 14( 2 ):125 -131. ORiain S. Br Med J. 1973; 3( 5881 ):615 -616. What makes you curious? Send your concern, and if its picked, well answer it in a future “Just Curious” column.Submit a Question