Medial Collateral Ligament Injury

The medial collateral ligament (MCL) is a thick band of tissue, or ligament, on the inside of the knee. The ligament runs from the thighbone (femur) to the shinbone (tibia). The MCL prevents the leg from overextending inward, stabilizes the knee joint and allows for smooth rotation during movement.

Along with anterior cruciate ligament (ACL) injuries, MCL injuries are among the most common knee injuries in athletes and active people.


MCL sprains occur from a strain, partial tear or complete tear when the ligament receives a sudden blow to the knee, most often during sports activities.

The following sports—especially at the college or professional level— are among those that pose the greatest risk of MCL injury:

  • Football
  • Weightlifting
  • Skiing
  • Hockey
  • Volleyball
  • Soccer
  • Basketball
  • Rugby

In addition, those who have previously strained or torn the MCL are at increased risk of it happening again.

The cause could also be non-sports related. For instance, a car crash could result in a direct blow that damages the ligament.

MCL tears and sprains can cause significant knee pain and destabilization of the knee joint. Symptoms of an MCL injury may include:

  1. A popping or snapping sound during the initial injury
  2. Immediate pain and swelling of the injured knee
  3. A feeling of instability or looseness in the injured knee
  4. A feeling of the injured knee buckling or “giving out” during movement
  5. Limited range of motion in the injured knee

MCL sprains or tears often occur alongside damage to the meniscus or the anterior cruciate ligament (ACL). These multi-ligament injuries often cause significant pain, stiffness, and instability in the knee joint and require immediate medical attention.

If you injure your knee and experience knee pain accompanied by stiffness, swelling, decreased range of motion or a feeling of instability in the knee joint, you should call our office immediately or take advantage of our walk-in clinic in Haverhill and Andover Monday – Friday, 8am-12pm and 1pm-3pm.


Your doctor will examine and palpate your knee to see if there’s pain and swelling. They may also put pressure on the ligament to see if it’s loose, indicating a torn MCL.

Other tests may include magnetic resonance imaging (MRI), ultrasound or x-ray to check for broken bones or other injuries

Based on the exam and test results, your doctor will categorize your MCL injury by grade:

  • Grade I – indicates a mild sprain or stretching of the ligament fibers. There may be mild to moderate pain and slight swelling, but the knee joint remains stable.
  • Grade II – injuries indicate a more severe sprain or stretching of the ligament. Pain and swelling may be more severe, and there may be noticeable instability in the knee joint.
  • Grade III – injury is a complete ligament tear. Destabilization of the knee joint accompanies severe pain and swelling. Grade III tears with concurrent meniscus or ACL injury may require surgical repair.


Grade I
A combination of rest, ice, compression, and elevation of the knee (the RICE method) is the typical treatment for Grade I MCL injuries. In addition, non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, can help control pain and inflammation as a Grade I sprain heals. A knee brace may also help stabilize the knee during healing. A Grade I sprain typically heals within a week or so.

Grade II
Treatment of Grade II MCL injuries also uses the RICE method. In addition, NSAIDs and a brace can alleviate knee pain. Grade II injuries may require physical therapy if the range of motion doesn’t adequately return. Grade II injuries can take up to a month to heal.

Grade III
MCL injuries that occur without damage to other structures in the knee may heal on their own with the RICE method and NSAIDs to control pain and swelling. However, these injuries are more severe, so they can take up to two months to completely heal.

Grade III MCL ruptures with an injury to another part of the knee typically require surgical repair, which is usually an outpatient procedure.
First, your surgeon will make a small incision in your knee and insert a small tube-shaped instrument known as an arthroscope to inspect the site. Then, they will use tendons from your body or a donor to reconstruct the MCL.

Your doctor may recommend physical therapy during recovery.

If you suffer a knee injury, please call our office at (978) 794-1946 or (603) 898-2244 immediately for a consultation with one of our doctors or take advantage of our walk-in clinic in Haverhill and Andover Monday – Friday, 8am-12pm and 1pm-3pm.

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