What is it?
The medial collateral ligament (MCL) is one of the four ligaments that stabilize the knee along with the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and lateral collateral ligament (LCL). The MCL is located on the inner side of the knee, and it prevents the knee from collapsing inward. MCL sprains are very common, especially in sports that require quick side-to-side movements, such as hockey, skiing, soccer, and American football. A sprain of the MCL can range from a mild injury to a complete tear of the ligament.
Causes
The MCL can be injured in a few different ways. One type of injury happens when another player contacts the outside of the lower thigh, the knee, or upper part of the lower leg, which forces the knee to collapse inward. The other common injury is a twisting motion on a bent knee that also causes the knee to collapse inward.
Risk Factors
• Participation in contact and collision sports
• Sports requiring pivoting, shifting, and quick direction changes
Symptoms
• Hearing or feeling a popping or tearing sensation along the inner side of knee
• Pain, particularly along the inner part of the knee
• Swelling and bruising of the inner side of the knee
• Painful movement of the knee, sometimes with stiffness
• Pain when putting weight on the knee
• A feeling giving way in the knee, especially when attempting to quickly change direction
Diagnosis
A sports medicine physician can accurately diagnose most MCL sprains by talking with the athlete and performing a thorough examination of the injured knee. The physician will evaluate for swelling, bruising, pain, knee movement, and leg strength. The ligaments will be tested during the exam. Additional tests such as x-ray, ultrasound, or MRI may also be used to evaluate the injury.
Treatment
Treatment typically includes rest, ice, elevation, compression, knee braces, and pain relievers. If the athlete is unable to put weight on the leg, crutches can be used. The majority of athletes who sprain the MCL are able to fully return to the same type of sports activity without surgery. Injuries that involve multiple knee structures, such as ACL or meniscus tears, may require surgery. Rarely, athletes may have surgery because of continued feelings of giving way in spite of leg strengthening and bracing.
Injury Prevention
Balance, strength and power exercises may decrease the risk of MCL sprains. Studies have not shown that knee braces designed to prevent side-to-side movement during sports lower the risk of MCL sprains. In fact, bracing might interfere with athletic performance by reducing speed and agility.
Return to Play
Return to sports is possible once pain is well controlled, and the athlete has full knee movement with good strength, power and balance. Knee braces may be recommended after the injury.
AMSSM Member Authors: Kyle Goerl, MD, Robert Dimeff, MD
References
Morelli V, Bright C, Fields A. Ligamentous injuries of the knee: anterior cruciate, medial collateral, posterior cruciate, and posterolateral corner injuries. Primary Care: Clinics in Office Practice. Vol 40;2(June2013).
Phistikul P, James SL, Wolf BR, Amendola A. MCL injuries of the knee: current concepts review. Iowa Orthop J. 2006;26:77-90.
