The lateral collateral ligament, or LCL, is one of the four major ligaments of the knee. It runs alongside the outer side of the knee and connects the thigh bone and the smaller bone of the lower leg, called the fibula.

Injuries to the LCL are sometimes seen in contact sports, where collisions with other players are common.

It is typical for the LCL to be injured in conjunction with other structures of the knee, like the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). An isolated injury to the LCL is extremely rare.

LCL tears are classified by grades, depending on the severity of the injury:

• Grade I: The LCL is stretched, but not torn.
• Grade II: The LCL is partially torn.
• Grade III: The LCL is completely torn through.

Tears of the lateral collateral ligament often occur due to a blow to the inside of the knee that forces the knee to overextend outwards.

LCL tears are common in these sports:

• Basketball
• Football
• Hockey
• Skiing

Symptoms of LCL tears can be similar to symptoms associated with other knee injuries. Usually, the knee does not swell with an LCL tear, but you may experience other symptoms like:

• Pain on the outside of the knee
• Stiffness
• A feeling that the knee is loose or unstable

If you have experienced an injury to the knee and have symptoms of an LCL tear, make an appointment to see an orthopedic specialist. During your appointment, your doctor will examine the knee for damage to the ligament. If your doctor notices tenderness over the femur or tibia where the lateral collateral ligament connects, this may indicate an LCL tear.

Most of the time, an LCL tear occurs with more serious injuries to the knee. For this reason, your doctor will do tests to make sure you do not have any other damage to the knee, like an a ACL or PCL tear.

In order to make a diagnosis, your doctor may prescribe the following imaging tests:

• X-rays to rule out fracture of the leg
• MRI to show the extent of damage and check for damage to other muscles and ligaments of the knee

LCL tears are generally treated using non-operative treatments. Immediately following injury to the LCL, you will be instructed to follow certain guidelines to reduce pain and swelling, like:

• Resting the leg
• Icing periodically throughout the day
• Taking non-steroidal anti-inflammatory medications, like ibuprofen

As your pain and swelling reside, you’ll begin a physical therapy program to stretch and strengthen the knee, restoring range of motion and stability. You will also be required to wear a brace to protect and stabilize the knee when active.

Try these exercises to help address your condition:

Below is a PDF of the Exercise Program

Knee LCL Injury

LCL tears rarely need surgery, because the ligament usually heals itself. Surgery is typically only needed when other ligaments or structures of the knee are also injured.

The time it takes you to recover from an LCL tear will depend on the severity and grade of your injury:

• Grade I: Recovering from a grade I LCL injury takes about three weeks to heal.
• Grade II: Recovery from a grade II partial tear of the LCL can take three to six weeks.
• Grade III: Complete tears of the LCL take more than six weeks to heal.

You can return to play when you have regained full range of motion and strength without any pain, and when instructed by your doctor. Once you recover from an LCL tear, you will most likely need to wear a brace to protect the knee while playing to reduce the risk of a recurrent tear.