Lateral Collateral Ligament
Your lateral collateral ligament (LCL) is a cord-like ligament on your knee’s lateral (outer) side that forms part of the posterolateral corner. It originates from the lateral femoral epicondyle, joins the bicep femoris tendon before attaching to the fibula’s head. 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, 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: e.g. ACL, PCL, meniscus and posterolateral corner.
What Causes an LCL Injury?
Your lateral collateral ligament’s primary function is to resist varus force and external tibial (shin bone) rotation. This force occurs if your tibia/foot is forced inwards to the knee or when your foot is grounded, and your knee twists medially.
The LCL is injured when the varus force is too high for the ligament to resist. The ligament overstretches. This overstretch can occur through a sharp change in direction, twisting the knee on a planted foot. Othe causes include incorrect landing technique, hyperextension of the knee or a blunt force hit to the knee, such as in a 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.
LCL Injury Severity?
The severity and symptoms of a knee ligament sprain depend on stretching or tearing the knee ligament. You may notice an audible snap or tearing sound at the time of your ligament injury.
In a mild Grade I LCL sprain, the knee ligament has a slight stretch, but they don’t tear. Although the knee joint may not hurt or swell very much, a mild ligament sprain can increase a repeat injury risk.
With a moderate Grade II LCL sprain, the knee ligament tears partially. Knee swelling and bruising are common, and knee joint use is usually painful and challenging. 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. Other structures are at risk of injury with these more severe tears, including the meniscus or ACL.
How is an LCL Injury 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 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 helpful. 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. These modalities, plus exercises to strengthen your knees, helps to prevent a future tear.
When a Grade II sprain occurs, a weight-bearing brace or some supportive taping is commonplace in early treatment. This support 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 no longer have pain. The ligament healing may take a minimum of 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 healing 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, Your physiotherapist can gradually unlock the knee brace to allow additional knee movement as tolerated. The aim is to allow for complete knee ligament healing and slowly return to normal activities. Severe LCL injury treatment via physiotherapy is a primary choice. However, we recommend the advice of a knee surgeon. Patients may not return to their full level of activity for 3 to 4 months. We highly recommend seeking professional advice from a healthcare practitioner specialising 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 damage. Your physiotherapy treatment will aim to:
- Reduce pain and inflammation.
- Normalise joint range of motion.
- Strengthen your knee: especially quadriceps (esp VMO) and hamstrings.
- Strengthen your lower limb: calves, hip and pelvis muscles.
- Improve patellofemoral (knee cap) alignment
- Normalise your muscle lengths
- Improve your proprioception, agility and balance
- Improve your technique and function, e.g. walking, running, squatting, hopping and landing.
- Guide your return to sport, activities and exercises.
- Minimise your chance of re-injury.
We strongly suggest that you discuss your specific knee rehabilitation plan with your trusted healthcare practitioner after a thorough examination by a knee injury clinician such as a sports physiotherapist, sports physician or knee surgeon.
Most LCL injuries resolve well with conservative management. However, surgery may occur if there is significant ligament disruption, e.g. Grade III. Knee surgery may also be required if there is a considerable combination of injuries involving the ACL, posterolateral corner or meniscus. In these cases, your knee surgeon, physiotherapist, and doctor’s opinions will guide the need for knee surgery.
Risks of knee surgery include infection, persistent instability and pain, stiffness, and difficulty returning to your previous activity level. 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 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 your specific knee ligament injury and the demands of your competition.
How to Prevent Recurrence of LCL Injury?
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 carries risk. Please discuss with your physiotherapist or surgeon.
Common Causes - Knee Pain
Knee pain can have many origins from local injury, referred pain, biomechanical issues and systemic issues. While knee pain can appear simple to the untrained eye, a thorough assessment is often required to ascertain the origin of your symptoms. The good news is that once a definitive diagnosis is determined, most knee pain quickly resolves with the correct treatment and rehabilitation.
Knee Ligament Injuries
- Knee Ligament Injuries
- ACL Injury
- PCL Injury
- MCL Sprain
- LCL Sprain
- Posterolateral Corner Injury
- Superior Tibiofibular Joint Sprain
Knee Meniscus Injuries
- Chondromalacia Patella
- Fat Pad Syndrome
- Patella Dislocation
- Patellofemoral Pain Syndrome
- Osgood Schlatter’s Disease
- Sinding Larsen Johansson Syndrome
Knee Tendon Injuries
- Corked Thigh
- Thigh Muscle Strain
- Hamstring Strain
- ITB Syndrome
- Popliteus Syndrome
- Muscle Strain (Muscle Pain)
- DOMS – Delayed Onset Muscle Soreness
Children’s Knee Conditions
Other Knee-Related Conditions
- Runner’s Knee
- Plica Syndrome
- Stress Fracture
- Overuse Injuries
- Restless Legs Syndrome
For specific information regarding your knee pain, please seek the assistance of a healthcare professional with a particular interest in knee condition, such as your physiotherapist.