Radiofrecuency and Supervised Exercise Versus Supervised Exercise in the Treatment of Patellofemoral Pain Syndrome.

Inclusion Criteria: * Patients diagnosed with patellofemoral pain syndrome more than 6 months old. * Have an age between 18 years and 50 years. * Adult patients with anterior knee pain were referred by a primary care physician at a public health center in southern Spain. Those participants with a self-reported pain intensity = 30 mm on the Visual Analog Scale (VAS) and a score \<45 points in personal psychology The Apprehension Scale (PPAS) \[bathrobe 2017\], were invited to participate. The PPAS is a valid, reliable and easy-to-use tool for assessing the apprehension of subjects to receive electrical stimulation therapy \[bathrobe 2005\]. Exclusion Criteria: * Any contraindication for the use of MDR * Present cognitive alterations. * Have undergone conservative or surgical treatment of the knee in less than 6 months. * Having received injections of corticosteroids or hyaluronic acid; impaired cognition or communication; and be involved in an ongoing medical-legal dispute.