What type of injury is characterized by pain and swelling as a result of exposure to cold?

Chilblains are a type of injury that occurs when skin is exposed to cold, which leads to painful inflammation and swelling, primarily affecting extremities such as fingers and toes. This condition typically develops when cold, damp conditions cause an inflammatory response in the skin, resulting in symptoms like redness, itching, swelling, and blisters. Chilblains do not cause tissue damage like frostbite but can be very uncomfortable.

The other conditions, while they may also involve the effects of extreme temperatures, have different characteristics. Frostbite refers to the freezing of skin and underlying tissues due to exposure to extremely low temperatures, which can lead to more severe damage. Heat stroke is a life-threatening condition caused by overheating, often due to prolonged exposure to or physical exertion in high temperatures. Trench foot is a condition that arises from prolonged exposure to damp and cold conditions, leading to foot injuries but with different mechanisms and symptoms than chilblains.