Injuries to the anterior cruciate ligament (ACL), medial collateral ligament (MCL), and posterior cruciate ligament (PCL) are common knee injuries. These ligaments play crucial roles in stabilizing the knee joint. ACL injuries often occur during sports activities and involve sudden stops, changes in direction, or direct impact to the knee. MCL injuries can result from a direct blow to the outer side of the knee. PCL injuries are typically caused by strong impact or landing on a bent knee. Symptoms include immediate pain, swelling, instability, and difficulty bearing weight on the affected leg.