Do i use heat or ice pack for my knee ligament injury. thanks?

See below : When you're first injured, ice is a better choice than heat for about the first 3 days or so. Ice numbs pain and causes blood vessels to constrict, which helps reduce swelling. Ice the area for just 15 to 20 minutes every four to six hours. After 3 days, heat can increase blood flow to an injury, which helps promote healing and relaxes muscles which promotes pain relief.