What is a Lateral Collateral Ligament Injury?
The lateral collateral ligament (LCL) runs along the outer side of the knee, starting from the top part of the fibula (the bone on the outside of the lower leg) to the outside part of the lower thigh bone. Its main function is to help keep the outer side of the knee joint stable.
An LCL injury can be a stretch, partial tear, or a complete tear of the ligament. The injury usually occurs when the knee joint is pushed from the inside, which results in stress being placed on the outside part of the joint.
An LCL injury often occurs along with other ligament injuries, including ACL, PCL, and MCL, and is frequently seen along with knee dislocations. LCL injuries are much less common than MCL injuries because the opposite leg usually protects against direct blows to the inside of the knee. However, an LCL injury can occur when the leg is extended in front of the body, such as when an athlete is attempting to gain control of the ball in soccer or rugby.
Symptoms of an LCL Injury
Symptoms of an LCL injury include swelling of the knee, catching or locking of the knee when the knee is moved, tenderness or pain along the outside of the knee, and a feeling like the knee is going to give way—or it actually does give way—during movement or stress.
Treatment of an LCL Injury
Immediately after the injury occurs, RICE should be applied: Rest, Ice, Compression, and Elevation. A doctor should examine the knee as soon as possible and may order x-rays or an MRI if needed. For grades 1 and 2 LCL injuries, the suggested treatment is the use of crutches to keep weight off the knee. A knee brace can be helpful for some patients. Nonsteroidal anti-inflammatory drugs are usually prescribed for the swelling and pain. A grade 3 injury, which involves a complete tear, is usually treated with arthroscopic surgery. Rehabilitation for all grades of injury will include range of motion exercises as well as exercises to strengthen the quadriceps and stretch the knee.