Most often a blow to the side of the knee that stretches or tears the ligament on the side of the knee. Such blows frequently occur in contact sports like football or hockey.
- A popping sensation and the knee may buckle sideways.
- Pain and swelling are common.
Most sprains of the collateral ligaments will heal if the patient follows a prescribed exercise program. In addition to exercise, the doctor may recommend ice packs to reduce pain and swelling and a small sleeve-type hinge brace to protect and stabilize the knee. A sprain may take 4 to 6 weeks to heal. A severely sprained or torn collateral ligament may be accompanied by a torn ACL, which usually requires surgical repair.