Lateral collateral ligament (LCL) injury of the knee is a relatively uncommon but serious injury that affects the ligament on the outer side of the knee joint. It occurs when the LCL, which is responsible for providing stability to the knee joint, is stretched or torn. The injury may result from direct trauma to the knee, such as a blow to the outer knee, or from twisting or bending the knee in an unnatural way.
Symptoms of an LCL injury may include pain on the outer side of the knee, swelling, stiffness, and difficulty moving the knee. In more severe cases, there may be a visible deformity, such as a bump or a bulge, and the knee may feel unstable or give way.
Risk factors for LCL injury include participation in sports that involve sudden stops, pivoting or twisting movements, or direct blows to the knee. People who have a history of knee injuries or who have laxity or looseness in their knee joint may also be at increased risk.
Diagnosis of an LCL injury typically involves a physical examination by a healthcare provider, who will assess the knee for swelling, pain, and stability. X-rays or magnetic resonance imaging (MRI) may also be used to evaluate the extent of the injury and rule out other possible causes of knee pain.
Differential diagnoses of an LCL injury may include other ligament injuries of the knee, such as anterior cruciate ligament (ACL) or medial collateral ligament (MCL) injuries, or meniscus tears.
Treatment for an LCL injury may depend on the severity of the injury. Mild to moderate LCL injuries may be treated with rest, ice, compression, and elevation of the affected leg, along with nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation. Physical therapy may also be prescribed to help restore strength and mobility to the knee joint. In more severe cases, surgery may be required to repair or reconstruct the torn ligament.
Recovery timeframes for an LCL injury can vary depending on the severity of the injury and the chosen treatment option. Mild to moderate injuries may heal within several weeks to a few months with conservative treatment, while more severe injuries may require several months of rehabilitation and recovery following surgery.
Prognosis for an LCL injury is generally good with appropriate treatment, although full recovery may take several months. With proper rehabilitation and the right measures to prevent re-injury, most people with an LCL injury are able to return to their previous level of activity.