Cold compresses should be applied immediately after a ligament strain, not hot compresses, usually for about 10-20 minutes, which will help to reduce bleeding from the injured blood vessels and avoid further formation of swelling, as well as reduce inflammatory pain. If hot compresses are applied, it will lead to further increase in bleeding from the blood vessels, resulting in swelling at the site of the ligament injury and making recovery more difficult. Cold compresses should be applied along with external fixation in a cast or brace, and after fixation, the affected limb should be elevated above the level of the heart to reduce edema by gravity. After 48 hours after the injury, hot compresses can be applied, at this time, the injured blood vessels have basically closed, and there will be no more increased bleeding, through hot compresses can increase local blood circulation, promote the absorption of inflammatory metabolic products, but also to promote the repair of damaged ligaments.