The difference between cold compresses and hot compresses are the following: 1, the difference in the role of local, cold compresses are mainly through the contraction of local blood vessels, so as to achieve the role of pain relief or to make the bleeding capillaries so that the bleeding is quiescent, thereby preventing further aggravation of swelling. The difference in the role of some diseases, if it is a soft tissue injury, usually the first 24 hours is supposed to use cold compresses, because cold compresses can minimize the further aggravation of its swelling, but also to reduce the pain threshold of the skin, so as to relieve pain. The hot compress is usually considered after 24 hours of injury, and the swelling is completely stable, to promote local blood circulation and speed up the relief of local swelling and pain. 3, if it is applied to some inflammatory diseases, cold compresses and hot compresses are also different. Generally in the acute inflammatory edema period, such as local redness, swelling, heat and pain, it is recommended to use cold compresses. And to the chronic pain period, in addition to local swelling, there is no skin temperature increase, skin flushing and other conditions, hot compresses are better.