"Patellofemoral pain" refers to pain that occurs in the front of the knee, specifically around the area where the knee cap (patella) and the thigh bone (femur) meet. Full definition
Symptoms are similar to that of patellofemoral pain syndrome with pain and swelling at the front of the knee especially over and around the kneecap or patella. (sportsinjuryclinic.net)
Runners have a high rate of patellofemoral pain syndrome, in part because the motion of running involves bending the knee so many times. (health.com)
Symptoms are similar to patellofemoral pain as the kneecap rubs on the bone underneath causing swelling and pain. (sportsinjuryclinic.net)