The soft tissues and fat pad in the front knee can be causes of pain as well. The repetitive pressure and stress between the femur and patella in these sports can result in softening of the cartilage and abnormal loading of the underlying bone.

Runner's knee presents as activity-related pain in the front of the knee and around the kneecap. Runner's knee involves the kneecap, quadriceps tendon, patellar tendon, and the associated soft tissues that are critical to extension of the knee. More recently, however, it has been recognized that overloading of the underlying ("subchondral") hercule can be a substantial source of pain, as it has a rich nerve supply. Historically, "runner's knee" was attributed to irritation and softening of the cartilage lining on the undersurface of the kneecap ("chondromalacia").

Other terms that have been used to describe this condition are "anterior knee pain", "chondromalacia patella", or "patellofemoral pain syndrome (PFPS)". This includes repetitive jumping sports like basketball or volleyball, as well as skiing, cycling, and soccer. Runner's knee is a term used to describe a constellation of symptoms of knee pain that is frequently encountered in running athletes. While classically associated with long-distance running, any activity that places significant stresses on the front of the knee joint ("patellofemoral") can result "runner's knee".

While the pain develops during.