Inclusion Criteria:  Age between 30 and 65; Signs and symptoms of isolated patellofemoral osteoarthritis present in one or both knees; Radiographic signs of isolated patellofemoral osteoarthritis (according to Iwano et al stage 1-3 classification) or chondropathy (assessed on MRI) with K-L grade of the other compartments ≤ 2. [PMID: 2302884 - PMID: 27979409] ; Hemoglobin > 11 g/dl; Platelet count > 150,000 plt/mm3 (Recently performed CBC exam); No clinically significant electrocardiographic alterations (Recently performed ECG). Ability and consent of patients to actively participate in clinical follow-up; Signature of informed consent.  Exclusion Criteria:  Patients unable to express consent; Patients who have undergone intra-articular infiltration of another substance within the previous 6 months; Patients undergoing knee surgery within the previous 12 months; Patients with malignant neoplasms; Patients with rheumatic diseases; Patients with diabetes; Patients with hematologic diseases (coagulopathies); Patients on anticoagulant-antiaggregant therapy; Patients with thyroid metabolic disorders; Patients abusing alcoholic beverages, drugs or medications; Body Mass Index > 35; Patients who have taken NSAIDs in the 3 days prior to blood draw; Patients with cardiovascular disease for which a 60 mL blood draw would be contraindicated; Patients with a recently performed blood test with Hb< 11 g/dl and Platelets < 150,000 plt/mm3. Previous treatment of patellar dislocation Iwano score of grade 4.