The lateral collateral ligament (LCL) is a band of tissue on the outer side of the knee, connecting the thigh bone (femur) to the smaller lower leg bone (fibula). It stabilizes the knee joint by preventing excessive outward movement and resisting inward forces (varus stress). LCL injuries, ranging from a stretch to a complete tear, are common, especially in activities with sudden impacts or twisting motions.
Key Indicators of an LCL Injury
Pain along the outside of the knee is a common sign of an LCL injury. This pain can be sharp at the moment of injury, evolving into a dull ache, with intensity varying by severity. The outer knee may also become sensitive to the touch, indicating localized tenderness over the ligament.
Swelling commonly develops around the injured area, typically on the outer aspect of the knee. This inflammation can appear immediately or gradually over several hours following the injury. Swelling can lead to stiffness, making it difficult to fully bend or straighten the knee. Bruising may also become visible around the outside of the knee, resulting from small blood vessel tears beneath the skin.
A sensation of instability or looseness in the knee is another frequent indicator of an LCL injury. Individuals might describe feeling as though their knee could “give way” or buckle, especially when attempting to turn or place weight on the affected leg. This feeling of instability can make walking difficult and might persist if the injury is more severe. A popping sound might also be heard at the time of the injury, signaling the tearing or stretching of the ligament.
How LCL Injuries Occur
LCL injuries result from forces that push the knee beyond its normal range of motion. A common mechanism is a direct blow to the inside of the knee, forcing it outward and stressing the LCL. This impact often occurs in contact sports.
Hyperextension of the knee, where the joint extends beyond its normal straight position, can lead to LCL damage. Sudden twisting motions or rapid changes in direction, especially when the foot is planted, can also strain or tear the ligament. These movements are common in sports like football, soccer, basketball, and skiing. Falls or other accidents involving unusual knee stress can also cause LCL injuries.
Next Steps After Suspecting an LCL Injury
If an LCL injury is suspected, seeking professional medical evaluation is important for an accurate diagnosis and appropriate treatment plan. A doctor or orthopedic specialist can assess the knee through physical examination and may order imaging tests like X-rays or MRI to determine the injury’s severity. Prompt medical attention helps to prevent further damage and ensures proper healing.
While awaiting medical consultation, several self-care steps can help manage symptoms. Applying ice to the injured area for 10 to 20 minutes at a time can help reduce swelling and pain. Elevating the leg above heart level also aids in minimizing swelling. Resting the affected knee and using compression, such as an elastic bandage, can provide support and further reduce inflammation. These initial measures, often referred to as the RICE method (Rest, Ice, Compression, Elevation), are temporary and should be followed by a comprehensive medical assessment.