Medial Collateral Ligament (MCL) Sprain

The medial collateral ligament sprain is a tear to one of the four major stabilizing ligaments of the knee. The medial collateral ligament (MCL) is a structure that helps keep the normal relationship of the femur (thigh bone) and the tibia (leg bone) along the inner side of the knee. The MCL prevents the knee from buckling inward and is the ligament most commonly injured in sports. When torn, this ligament usually heals, although it may heal in a lengthened position (slightly loose). Sprains are classified into three grades. In a first-degree sprain the ligament is not lengthened but is painful. With a second-degree sprain, the ligament is stretched but still functions. With a third-degree sprain, the ligament is torn and does not function.

MCL sprains are caused by force that exceeds the strength of the ligament. Most commonly this injury is the result of a direct blow to the outer side of the knee, usually while the foot is on the ground. This injury may also be a result of a non-contact injury.

Initial treatment consists of medications and ice to relieve pain and reduce the swelling of the knee. Walking with crutches until you walk without a limp is often recommended (you may put full weight on the injured leg). Your physician may recommend a knee brace with a hinge to help regain knee motion while protecting the MCL. Range-of-motion, stretching, and strengthening exercises may be carried out at home, although referral to a physical therapist or athletic trainer is usually recommended. Rehabilitation of MCL sprains generally concentrates on reducing knee swelling, regaining knee range of motion, regaining muscle control and strength, and a short period of bracing. For severe MCL sprains or those associated with other knee ligament injuries, surgery may be recommended.