For the skae of semantic precision:

"Chilblains, also called Perniosis or blain, is a medical condition similar to frostbite or trench foot. Chilblains are caused by exposure of skin to damp cold. Small blood vessels below the skin are damaged, but there is no freezing of tissue, thus distinguishing it from frostbite.

The condition is also distinguished by numbing of the affected area and the appearance of blisters or open sores. Chilblains do not usually cause permanent injury, but can result in severe damage if left untreated. Some patients have reported a sensitivity to cold in the affected area, long after the condition has healed. They are most common in the young and the elderly, and are more likely to occur in women.

They can be prevented by keeping the feet and hands warm in cold weather. A chilblain can chap, crack, or ulcerate; and then is known as a kibe."

Wikipedia