Injury to the lateral collateral ligament or LCL (the ligament along the outer side of your knee) can cause instability to your knee. Since the ligament connects the thigh bone to the small bone of your lower leg and ankle, LCL injury can cause symptoms like inflammation and lack of knee joint stability.

Symptoms of Lateral Collateral Ligament (LCL) Injury

LCL injury can cause mild to severe symptoms, depending on the degree of damage involved. A mildly sprained ligament may not have any symptoms at all, but a partial or completely torn ligament may cause symptoms such as:

• A sensation of instability, such that your knee may give way when stressed
• A feeling of locking the joint when you move the knee
• Foot numbness or muscle weakness if the adjacent peroneal nerve is stretched during LCL injury or if it is pressed by swollen tissues
• Acute or mild pain
• Joint stiffness
• Knee swelling and tenderness

Causes of Lateral Collateral Ligament (LCL) Injury

An LCL injury usually occurs when the lateral collateral ligament is torn after a direct blow is sustained inside of your knee. This force results in stretching of the ligament on the outside of your knee, causing a tear. This injury commonly occurs in sports that involve quick and repetitive stops and turns, such as basketball, skiing, soccer, or those where violent collisions are involved, such as hockey or football.

Most injuries in the knee involve the supporting ligaments, not only the joint itself. Injuries involving the collateral ligaments are often caused by forces that push the knees sideways, usually due to contact injuries. Repeated stress can also cause injury to the ligament due to loss of normal elasticity.

Diagnosis of Lateral Collateral Ligament (LCL) Injury

1. Patient History and Physical Examination

Upon consultation, your doctor will ask about your medical history andsymptoms. He will conduct a physical examination to check on your injured knee, comparing it to the other one. LCL injury may be easily diagnosed with thorough physical examination.

2. Imaging Tests

To confirm the diagnosis, your doctor may order other tests such as:

• X-rays. This test will help find out if there is any associated fracture or broken bone, however, it will not show LCL injury.
• Magnetic resonance imaging or MRI. This imaging technique helps examine your soft tissues, including the lateral collateral ligament.

3. Grades of LCL injury

The diagnosis of LCL injury is completed by describing the extent of injury, which is classified into grades:

• Grade 1: There is minor pain and some tenderness at the injured area, showing that there are small tears in your ligament.
• Grade 2: The knee is noticeably loose, which is shown when your knee opens up about 5 mm when manually moved. There is swelling, intense pain, and tenderness on the inner side of your knee, which indicates that there are larger tears in the ligament, though not torncompletely.
• Grade 3: There is considerable pain, tenderness and swelling on the inner side of your knee as well as marked joint instability. When moved, the knee opens up about half an inch. This means that the LCL is completely torn. The anterior cruciate ligament may also be torn.

Sometimes it may be difficult to evaluate the extent of injury or damage to the ligament because of intense swelling and pain in the knee. Your doctor may apply ice, raise your knee and ask you to use a light splint. When your pain is reduced, he may examine you again to make a more accurate diagnosis.

Treatment for Lateral Collateral Ligament (LCL) Injury

Treatment options for an LCL injury may depend on the severity as well as your lifestyle. Treatments for minor LCL injury may include:

• Using a splint
• Applying ice
• Keeping the knee elevated above the level of the heart
• Taking pain relievers
• Limiting physical activity temporarily
• Using crutches or a brace to protect the injured knee
• Taking a rehabilitation/physical therapy to strengthen the muscles and regain the normal range of motion

Treatment for severe injuries may also include surgery, physical therapy and rehabilitation. Surgery may involve ligament reconstruction or repair, especially when other ligaments or structures are involved.

Prevention of Lateral Collateral Ligament (LCL) Injury

LCL injury often occurs as a result of an accident and is therefore difficult to prevent. However, several measures could help reduce the risk of LCL injury, including:

• Using the proper techniques and body alignment during walking and other physical activities
• Doing stretching exercises regularly to promote adequate range of motion
• Strengthening the upper and lower leg muscles to stabilize the knee joint
• Practicing caution during sports that often involve knee injuries, such as soccer and football