The first thing you should do after a sprain is to apply a cold compress for about 15 minutes, which can effectively reduce the bruising, swelling and inflammatory edema after the injury and promote the recovery of the sprained area. After 48 hours, depending on the specific situation, apply hot compresses, such as hot water bags or fried hot coarse salt and herbal packs, can effectively increase the local temperature, dilate blood vessels, increase the blood supply of the arteries, provide more nutrients, electrolytes and energy to promote the sprain site of the activation of blood circulation and stasis, to increase venous return and promote the metabolism of inflammatory products, which can be very good to promote the recovery of the injured area. If there is no improvement within a short period of time or the condition is aggravated, we must go to the regular hospital in time, improve the local X-ray to exclude the possibility of fracture, choose a more reasonable treatment method, do not delay the condition.