LCL Injuries
An injury to the lateral collateral ligament, commonly called the LCL, can affect the stability of the knee and make walking, running, changing direction, or participating in sports more difficult. LCL injuries are commonly associated with forces that push the knee outward and place excessive stress along the outside of the joint.
The severity of an LCL injury can vary. Some injuries involve stretching or minor damage to the ligament, while others involve a partial or complete tear. LCL injuries may also occur with damage to other structures in the knee, particularly following a significant impact or twisting injury.
The lateral collateral ligament is a strong band of connective tissue located along the outside of the knee. It extends from the lower portion of the femur, or thighbone, to the fibula, the smaller of the two bones in the lower leg.
The LCL is one of the major ligaments responsible for knee stability. Unlike the anterior cruciate ligament and posterior cruciate ligament, which are located inside the knee joint, the LCL is positioned along the outside of the joint.
One of its primary functions is to resist forces that push the knee outward. It helps maintain proper knee alignment and provides stability during activities such as walking, running, pivoting, and changing direction.
The LCL also works with other structures along the outer and back portions of the knee. For this reason, a significant LCL injury may result in damage to multiple knee ligaments.
An LCL injury occurs when the ligament is stretched beyond its normal capacity or torn. These injuries are commonly called LCL sprains and range from relatively minor ligament damage to a complete rupture.
LCL injuries are generally classified according to severity.
- A grade 1 injury involves stretching and microscopic damage to the ligament without a significant tear. The knee generally remains stable.
- A grade 2 injury involves a partial tear. Pain, swelling, and tenderness may be more noticeable, and some instability may develop.
- A grade 3 injury is a complete tear of the LCL. Because the ligament can no longer provide normal support to the outside of the knee, substantial instability may occur.
The location of the injury can also vary. Damage may occur near the LCL’s attachment to the femur, within the ligament itself, or near its attachment to the fibula.
LCL injuries typically occur when a force is applied to the inside of the knee, pushing the knee outward and placing excessive tension on the ligament.
Sports are a common cause. Football, soccer, basketball, skiing, hockey, and other activities involving contact, rapid changes in direction, or unpredictable movements can place the LCL at risk.
A direct blow to the inside of the knee is another common mechanism. An athlete may be struck on the inner side of the knee during a collision, forcing the joint outward and overstretching or tearing the LCL.
LCL injuries can also occur without direct contact. An awkward landing, sudden pivot, or rapid change in direction may place excessive stress on the outside of the knee. Falls that force the knee to bend or twist abnormally can cause similar injuries.
More significant trauma, including motor vehicle collisions or falls from substantial heights, may result in complex injuries involving the LCL and other knee structures.
Pain along the outside of the knee is one of the most common symptoms. The pain may be concentrated near the ligament or extend into surrounding tissues.
Swelling can develop following the injury, although the amount varies depending on its severity and whether other structures are involved. Tenderness along the outside of the knee is also common.
Instability can occur with more substantial LCL injuries. The knee may feel loose or unreliable and may seem to shift sideways or give way while standing, walking, or participating in physical activity.
Some people experience stiffness or difficulty fully bending or straightening the knee. Running, pivoting, climbing stairs, and changing direction may increase discomfort.
Bruising may develop after more significant trauma. In some cases, numbness, tingling, or weakness in the lower leg or foot may occur if a nearby nerve has also been affected.
Diagnosing an LCL injury begins with a review of how the injury occurred and the symptoms that developed afterward.
During a physical examination, the physician will evaluate tenderness, swelling, range of motion, and knee stability. Specific stress tests are used to determine whether the LCL is providing normal resistance along the outside of the knee.
X-rays will be ordered to identify fractures or other abnormalities. An MRI provides detailed images of the LCL and surrounding soft tissues and will help determine whether the ligament is partially or completely torn. MRI imaging can also identify injuries involving other ligaments, tendons, cartilage, or the meniscus.
Because significant LCL injuries can involve additional structures along the outside and back of the knee, a careful examination is important to determine the full extent of the injury.
At Orthopedic Associates of Northern California, our experienced orthopedic surgeons take the time to listen to your concerns, identify the source of your symptoms, answer your questions, and develop a personalized plan based on your needs. If you are struggling with knee pain or a knee injury, contact us to schedule a consultation at our Chico, California office.
