Patellofemoral pain syndrome refers to the clinical presentation of knee pain related to changes in the patellofemoral joint. Patellofemoral pain syndrome usually has a gradual onset of pain with none of the features associated with other knee diseases or trauma. It is often treated by physiotherapists, who use a variety of techniques including patellar taping. This involves the application of adhesive sports medical tape applied directly to the skin over the patella on the front of the knee. Patients often report an instantaneous improvement in pain and function after the tape is applied, but its longer term effects are uncertain.