Lateral Collateral Ligament
What is Your Lateral Collateral Ligament?
Your lateral collateral ligament (LCL) is a cord-like ligament on the lateral (outer) side of your knee, that forms part of the posterolateral corner. It originates from the lateral femoral epicondyle, joins the bicep femoris tendon before attaching to the head of the fibula. It is one of four major ligaments that help you to stabilise the knee joint. LCL sprain is the most common form of LCL injury. In isolation, a lateral collateral ligament injuries only account for 2% of all knee ligament injuries. Most LCL injuries occur in combination with, damage to other knee ligaments and structures. eg ACL, meniscus and posterolateral corner.
What Causes a LCL Sprain?
The main function of your lateral collateral ligament is to resist varus force and external tibial (shin bone) rotation, which occurs if your tibia/foot is forced inwards in relation to the knee or when your foot is grounded and your knee is twisted medially.
The LCL is injured when the varus force is too great for the ligament to resist and the ligament is overstretched. This can occur through a sharp change in direction, twisting the knee whilst the foot is fixed, incorrect landing technique, hyperextension of the knee or a blunt force hit to the knee, such as in football tackle or a motor vehicle accident. The incident usually needs to happen at speed but muscle weakness or incoordination predispose you to a ligament sprain or tear.
Knee Ligaments Injury Severity?
The severity and symptoms of a knee ligament sprain depend on the degree of stretching or tearing of the knee ligament. You may notice an audible snap or tearing sound at the time of your ligment injury.
In a mild Grade I LCL sprain, the knee ligament has a slight stretch, but they don't actually tear. Although the knee joint may not hurt or swell very much, a mild ligament sprain can increase the risk of a repeat injury.
With a moderate Grade II LCL sprain, the knee ligament tears partially. Knee swelling and bruising are common, and use of the knee joint is usually painful and difficult. You may have some complaints of instability or a feeling of the knee giving way.
With a severe Grade III sprain, the ligament tears completely, causing swelling and sometimes bleeding under the skin. As a result, the joint is unstable and can be difficult to bear weight. You may have a feeling of the knee giving way. Often there will be no pain or severe pain that subsides quickly following a grade 3 tear as all of the pain fibres are torn at the time of injury. With these more severe tears, other structures are at risk of injury including the meniscus and/or ACL.
How is a LCL Sprain Diagnosed?
On examination, your physiotherapist will look for signs of ligament injury. There will be tenderness over the ligament site, possible swelling and pain with stress tests. MRI may also be used to diagnose a knee ligament injury and look at other surrounding structures for combination injuries.
How Long does it take for an LCL Injury to Heal?
Treatment of an LCL injury varies depending on its severity and whether there are other combination injuries.
Grade I sprains usually heal within a few weeks. Maximal ligament strength will occur after six weeks when the collagen fibres have matured. Resting from painful activity, icing the injury, and some anti-inflammatory medications are useful. Physiotherapy will help to hasten the healing process via electrical modalities, massage, strengthening and joint exercises to guide the direction that the ligament fibres heal. This plus exercises to strengthen your knees helps to prevent a future tear.
When a Grade II sprain occurs, use of a weight-bearing brace or some supportive taping is common in early treatment. This helps to ease the pain and avoid stretching of the healing knee ligament. After a grade II injury, you can usually return to activity once the joint is stable and you are no longer having pain. This may take up to six weeks. Physiotherapy helps to hasten the healing process via electrical modalities, massage, strengthening and joint exercises to guide the direction that the knee ligament fibres heal. This helps to prevent a future tear and quickly return you to your pre-injury status.
When a Grade III injury occurs, you usually wear a hinged knee brace for up to six weeks, with a small amount of movement, and use crutches for 1-2 weeks to protect the knee ligament from weight-bearing stresses. As your pain resolves and knee ligament repairing occurs, the knee brace can be gradually unlocked to allow greater knee movement as tolerated. The aim is to allow for full knee ligament healing and gradually return to normal activities. Sever LCL injury is most successfully treated via physiotherapy and the advice of a knee specialist. Patients may not return to their full level of activity for 3 to 4 months. We highly recommend that you seek professional advice from a healthcare practitioner who specialises in knee ligament injuries to avoid long-term knee instability.
What is the Treatment for an LCL Injury?
Depending on the grade of knee ligament injury you can start to feel better within days to just a few weeks of the injury. Your physiotherapy treatment will aim to:
We strongly suggest that you discuss your knee ligament injury rehabilitation plan after a thorough examination from a knee injury specialist such as a sports physiotherapist, sports physician or knee surgeon.
Knee Ligament Surgery
Most LCL injuries resolve well with conservative management, however, surgery may be considered if there is significant ligament disruption eg Grade III. Knee surgery may also be required if there is a significant combination of injuries involving the ACL, posterolateral corner and/or meniscus. In these cases, the opinions of your knee surgeon, physiotherapist and doctor will guide the need for knee surgery.
Risks of knee surgery include infection, persistent instability and pain, stiffness, and difficulty returning to your previous level of activity. The good news is that better than 90% of patients have no complications post-surgery.
Post-operative knee rehabilitation is one of the most important aspects of knee surgery. The most successful and quickest outcomes result from the guidance and supervision of an experienced sports physiotherapist.
Your physiotherapy rehabilitation following knee surgery focuses on restoring full knee motion, strength, power and endurance. You'll also require balance, proprioception and agility retraining that is individualised towards your specific sporting or functional needs.
As mentioned earlier your sports physiotherapist is an expert in this field. We suggest you contact them for the best advice in your circumstances.
Your physiotherapist will guide your return to sport. It is highly variable and depends upon on your specific knee ligament injury and the demands of your sport.
How to Prevent Recurrence of LCL Injuries?
A knee strengthening, agility and proprioceptive training program is the best way to reduce your chance of a knee ligament sprain. Premature return to high-risk activities such as sport are best discussed with your physiotherapist or surgeon.
For more information, please ask the advice of your physiotherapist.
Common Treatments for a Knee Ligament Injuries
Helpful Products for Knee Ligament Injuries
FAQs for Knee Ligament Injuries
Knee Ligament Injuries
Children's Knee Conditions
Other Knee-Related Conditions
Share this page
Receive Special Offers and the Latest Injury Information
Enter Details Below to Signup: