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MCL Injuries

What is an MCL injury?

MCL stands for medial collateral ligament, one of four major ligaments that keep the knee from wobbling when you move. To understand MCL injuries, it helps to know a little about how the knee works.

The knee is a large joint where the shinbone (tibia) meets the thighbone (femur). Two ligaments — the posterior cruciate ligament (PCL) and the anterior cruciate ligament (ACL) — cross each other in the middle of the knee. They work together to keep the shinbone attached to the thighbone.

Two other ligaments run along either side of the knee. The lateral collateral ligament (LCL) runs along the outside and keeps the knee from bending out. The MCL is on the inside and keeps the knee from bending in.

When the knee suddenly bends inward with the foot bent outward, the MCL and other ligaments can tear, partially or all the way. These kinds of injuries can occur during collisions in football and soccer and during car accidents.

How do you evaluate MCL injuries?

MCL stability testing.
MCL stability testing.

If your child’s knee suddenly swells after an accident or injury, she may have a torn MCL or another serious knee problem.

To help protect your child from more injuries that could hurt her growing bones and joints, it is important to get a thorough evaluation and proper treatment early on. When injuries are discovered and treated early, children rarely need to have surgery to reconstruct their MCL.

When you come to our clinic , we will ask what happened before your child’s knee began to swell and hurt. Next, we will examine your child’s knee. To doctors trained in sports medicine, knees with MCL tears often feel loose.

We cannot be sure that your child has a torn MCL until the swelling in her knee has gone down, which usually takes seven to 10 days. We will likely take radiographs of your child’s knee to help find out what is wrong.

If it is not clear that the MCL is torn or if we think your child may have other injuries, we may ask your child to have an MRI.

Who gets MCL injuries?

MCL injuries, while common in adults, are less common for children. Teenage athletes are more likely to injure their MCL than other teenagers, especially if they play sports that put them at risk of colliding with other players from the side, such as football and ice hockey.

MCL injuries also sometimes happen in combination with ACL tears.

Older children are more likely to injure their MCL than children who are younger than age 12. Younger children more often break the bone where the ligament attaches.

What is your experience with MCL injuries?

We are expert at treating growing athletes. We have a team of doctors, physician assistants and physical therapists that treats these injuries.

How do you treat MCL injuries?

We emphasize treating mild MCL injuries through rehabilitation therapy whenever possible. Surgery is rarely needed.

Non-surgical treatment for MCL injuries

Most children with MCL injuries and no other injury to the knee do well after wearing a hinged knee brace for three to four weeks and participating in a rehabilitation program.

At Children’s, we provide a regular course of physical therapy designed especially for your child. Our aim is for your child to recover range of motion, rebuild strength and stability, restore balance and regain confidence in using her knee.

These services are available at our on-site sports lab.

Surgery for MCL and ACL injuries

A child who has an MCL injury and an ACL injury will probably need surgical reconstruction of the ACL once she has regained motion in her knee. Learn more about ACL injuries.