Lateral collateral ligament (LCL) sprains are rare. Most commonly, these injuries occur when something hits the inside of your knee while your foot is on the ground. Imagine, for example, you were playing football, got tackled on the inside of one of your legs while in mid-stride and had your knee pushed outward. This is a perfect example of how an LCL sprain can occur.
If you experience an LCL sprain, you will probably feel immediate pain and may hear a popping or tearing noise. Subsequently, you may find it difficult to walk.
What actually happens during an LCL sprain is a stretching or tearing of the LCL, one of four ligaments that connect bones around the knee joint. The LCL runs down the outside of each knee, connecting the femur (thighbone) to the fibula (one of the bones in your lower leg). The other three ligaments are the anterior cruciate ligament (ACL) in the front, the posterior cruciate ligament (PCL) in the back and the medial collateral ligament (MCL) on the inside. The LCL prevents excessive rotation of the tibia (shinbone) and reinforces side-to-side knee stability.
Injuries to the LCL are most common in contact sports or skiing, but they can occur anywhere, anytime, such as when someone slips on a patch of ice and lands awkwardly on his or her knee. Regardless of how they happen, however, injuries to the LCL often occur in conjunction with injuries to other parts of the knee. Most commonly, an ACL tear accompanies an LCL sprain.
If you suspect damage to your LCL or other knee structures, having your healthcare practitioner thoroughly examine your knee will establish what damage has occurred. Afterward, your healthcare practitioner can effectively care for the damage and promote healing.