How Do You Know if You Have an MCL Injury?

What is an MCL injury?

A medial collateral ligament injury, or MCL injury, is a common knee injury. You know you have an MCL injury because you experience pain, swelling, stiffness and knee weakness.
A medial collateral ligament injury, or MCL injury, is a common knee injury. You know you have an MCL injury because you experience pain, swelling, stiffness and knee weakness.

A medial collateral ligament injury, or MCL injury, is a common knee injury in both children and adults. This kind of injury is more common in athletes or people who lead an active lifestyle.

So how do you know if you have an MCL injury?

The MCL is a ligament in your knee joint. A ligament is a piece of thick tissue that keeps bones and cartilage together. This ligament is on the inside of your knee, or the medial side, and keeps your knee from moving horizontally. Your MCL connects your femur, the lower part of your thigh with your tibia, the top of your shin.

You may experience an MCL tear or sprain if your knee is forced too much to the side or too much pressure is applied to the side. This can cause your knee to move inward. When this happens, the ligament can become strained, partially torn, or completely torn.

You can injure your medial collateral ligament by doing activities that involve:

  • Bending
  • Twisting
  • Changing directions suddenly
  • Jumping 
  • Stop-and-go movements
  • Weaving movements

A common MCL injury happens when an athlete is hit on the outside of the knee during a contact sport like soccer or football. MCL tears also occur while taking part in sports like skiing, when you have to weave from side to side or stop quickly.

Symptoms of MCL injuries

People with an MCL injury usually exhibit some key symptoms. These include:

  • Pain on the inside of your knee
  • Swelling at the injury site
  • Stiffness
  • Mild to severe pain
  • The sense that your knee might give out or can’t support you

At the time of the injury, you may hear a popping sound. This may be the sound of the ligament tearing. Children may or may not have symptoms, depending on how serious their injury is.

Once the swelling subsides, you will probably be able to walk. You will probably still feel pain when bending or stretching. Since your knee isn’t stable, you might lose your balance more easily. This can cause falls.

MCL injury diagnosis and treatment

To diagnose an MCL tear or injury, your doctor will ask you to describe how the injury happened and if you’ve had any knee injuries before. They will also ask you how your knee feels since the injury happened. If you’re an athlete, your doctor might also ask you about your training and goals to determine the best way to treat your injury.

Your health care provider will give you a physical exam to examine your injury. This lets your doctor see the severity of your injury. MCL injuries are ranked from one to three, one being the mildest and three being the most serious. If your knee is quite swollen, your doctor may order magnetic resonance imaging (MRI) to get a better look.

Non-surgical treatment. MCL tears or injuries rarely require surgery to repair. Your doctor will probably tell you to follow the RICE method:

  • Rest
  • Ice
  • Compression
  • Elevation

To properly ice your injury, apply an ice pack with cold ice directly to the injury for 15 or 20 minutes. Remove for at least an hour before applying a new ice pack. Wear a brace or compression bandage to protect your knee as it heals and keep it from bending. Your doctor may also suggest crutches for support.

You might need physical therapy to help your knee heal and recover your full range of motion. This can also improve your balance and help your leg and knee regain their strength and muscle tone.

Surgical treatment. Most MCL injuries don’t require surgery. In some cases, your doctor might recommend surgery to repair or reconstruct your MCL. To repair the MCL, your doctor will make an incision at the knee to apply suture anchors. These fixtures will attach the ligament to the bone again. If your surgeon has to reconstruct your MCL, they can use your tendons or those from a cadaver.


Recovery time depends on the severity of the injury and the treatment plan. Returning to sports is gradual to let your injury properly heal.

For those who have a low-grade MCL injury, at least six weeks of rest is usually recommended. After that time, if you can walk without a limp, you can start to incorporate light exercise back into your routine. This includes low-impact activities like:

Your doctor might recommend that you wear a brace so that your knee stays protected and supported.

If you had surgery on your MCL, recovery will be a lot slower, usually between nine and twelve months.


Medically speaking, the term "myalgia" refers to what type of pain? See Answer

Cedars Sinai: "Medial Collateral Ligament Tears."

OrthoInfo: "Collateral Ligament Injuries."

Rady Children's: "Medial Collateral Ligament (MCL) Injuries."

Stanford Health Care: "Medial Collateral Ligament (MCL Injury)."

TeensHealth from Nemours: "Medial Collateral Ligament (MCL) Injuries."

UC San Diego Health: "MCL Sprains and Tears."

UCSF Health: "MCL Tear Treatments."