Your knee will hurt and start to swell. The level of pain is your first clue to the amount of damage done. As a rule, the more pain, the worse the sprain. First Aid for Sprained Knees Apply ice immediately to minimize pain and swelling. R est the injured knee and keep it immobile.
E levate the injured knee.
If the pain doesn't subside quickly or the knee turns black and blue and swells up like a balloon, it's time to call the doctor. The ligament is stretched, but not pulled out of shape. The ligament is stretched and lengthened like a piece of taffy. It may be partially torn. In many cases, mild sprains heal themselves.