Final answer:
Runner's knee is a common knee injury that often affects females. It is caused by overuse and can result in popping and instability, as well as hemarthrosis. Treatment involves rest, physical therapy, and strengthening exercises.
Step-by-step explanation:
Runner's knee, also known as patellofemoral syndrome, is a common knee injury that often affects females. It is caused by overuse and can occur in activities such as running, jumping, cycling, and weightlifting. Symptoms include popping and instability, as well as hemarthrosis or bleeding into the joint. Treatment typically involves rest, physical therapy, and strengthening exercises.