Hyperkeratosis simply means thickening of the skin; this thickening occurs as a natural defense mechanism that strengthens the skin in areas of friction or pressure. Abnormal anatomy of the feet, such as hammer toe or other toe deformities, can lead to corn or callus formation as can bony prominences in the feet. Footwear that is too tight or that exerts friction at specific points can also cause skin thickening that leads to corns and calluses. Abnormalities in gait or movement that result in increased pressure to specific areas can also be the cause.
It can be difficult to know why finger corns develop since they often don't appear at sites of obvious pressure. Finger calluses may develop in response to using tools, playing musical instruments, or using work equipment that exerts pressure at specific sites.
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