Lateral Collateral Ligament (LCL) Injury

Your lateral collateral ligament (LCL) is a narrow and strong ligament located on the outside (lateral aspect) of the knee. It is one of the four ligaments that stabilise the knee joint, alongside the medial collateral ligament (MCL) and the anterior and posterior cruciate ligaments within the knee. It connects the top of the shin bone (tibia) to the bottom of the thigh bone (femur) and works to resist forces applied to the inside of the knee (varus forces), such as when a ball hits the inside of the leg or knee. This is much less common than impact to the outside of the knee, meaning LCL injuries occur less frequently.  

What causes a lateral collateral ligament injury?

LCL injuries occur as a result of stretching and stressing the ligament past the point that it can safely handle. Often this results from excessive force to the inside of the knee (varus force) and various twisting motions at the legs and knees. Examples include:
  • Trauma/impact on the inside of the knee, such as getting hit with a ball or from a tackle
  • Sudden changes in direction, especially during fast-paced activities
  • Sharp twists at the knee while the foot is fixed on the ground
Those with muscle weakness, ligament laxity or a history of knee injuries are typically at a greater risk of sustaining an LCL injury.  

What are the symptoms?

The different levels of severity of injury include a ligament sprain, a partial tear, or a complete rupture. Symptoms can include:
  • Pain and tenderness in the outer knee
  • Swelling
  • Bruising
  • A ‘snapping’ or ‘popping’ sound as the injury occurs
  • Feeling unstable, like the knee is giving way
  • Difficulty walking on the affected leg
  • Catching at the knee joint

How are LCL injuries treated?

When the injury first occurs, it’s important to stop physical activity and avoid walking on the affected knee where possible. Following the PRICE principles (protection, rest, ice, compression and elevation) can help reduce the initial pain and swelling. If you have had a rupture or significant tear to your LCL, you may require sYou must haveyou have a diagnosis to confirm the extent of your injury, which may involve having an ultrasound, x-ray or MRI imaging. Your podiatrist can help you gradually rebuild the strength in your knee and surrounding muscles, and improve the range of motion in the joint, which will likely be restricted following your injury. This will likely focus on strengthening your quadriceps, hamstrings, calves, hips and pelvic muscles. Your podiatrist will work with you to both help your recovery and reduce the risk of re-injury in the future. This may look at the use of orthotics to control motion at the feet and legs, assessing the stability of your footwear, assessing your walking/running technique, teaching you how to strap your knee when needed, bracing, and physical therapy (strengthening and stretching).