The condition may result from acute injury to the<unk> or chronic friction between the<unk> and a groove in the femur through which it passes during knee flexion. Possible causes include a tight iliotibial band, neuromas, bursitis, overuse, malalignment, core instability, and<unk>  maltracking. Pain at the front or inner side of the knee is common in adults of all ages especially when engaging in soccer, gymnastics, cycling, rowing, tennis, ballet, basketball, horseback riding, volleyball, running, combat sports, figure skating, snowboarding, skateboarding and even swimming. The pain is typically felt after prolonged sitting. Skateboarders most commonly experience this injury in their non-dominant foot due to the constant kicking and twisting required of it. Swimmers acquire it doing the breaststroke, which demands an unusual motion of the knee. People who are involved in an active lifestyle with high impact on the knees are at greatest risk. Proper management of physical activity may help prevent worsening of the condition. Athletes are advised to talk to a physician for further medical diagnosis, as symptoms may be similar to more serious problems within the knee. Tests are not necessarily needed for diagnosis, but in some situations they may confirm diagnosis or rule out other causes for pain. Commonly used tests are blood tests, MRI scans, and arthroscopy. While the term<unk>  sometimes refers to abnormal-appearing cartilage anywhere in the body, it most commonly denotes irritation of the underside of the kneecap (or "patella"). The<unk> s posterior surface is covered with a layer of smooth cartilage, which the base of the femur normally glides smoothly against when the knee is bent. However, in some individuals the kneecap tends to rub against one side of the knee joint, irritating the cartilage and causing knee pain.
Chondromalacia patellae
Patellar tendinitis
Attenuated patella alta
Patellofemoral pain syndrome
Osteochondritis dissecans
Pes anserine bursitis
Retrocalcaneal bursitis
Ischial bursitis