Can a simple injection cure tennis elbow? new study aims to find out.

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: Patients with epicondylitis of the elbow: 1. Patients with clinical picture of epicondylitis; 2. Duration of symptoms \> 3 months 3. Ultrasound picture of short or long radial extensor carpal tendinopathy; 4. Age \> 18 and \< 65 5. Both sexes; 6. Failure, defined as persistence of symptoms, of other conservative treatments for at least 3 months; 7. Hemoglobin \> 11 g/dl; 8. Platelet count \> 150,000 plt/mm3 (Recently performed CBC examination); 9. Negative serological tests for HBsAg, HCV Ab, HIV-1-2 Ab 10. No clinically significant electrocardiographic changes (Recently performed ECG); 11. Ability and consent of the patient to actively participate in clinical follow-up; 12. Signature of informed consent. Exclusion Criteria: 1. Patients undergoing previous surgical treatment on the epicondylar tendons; 2. Patients undergoing epicondylar infiltration in the previous 6 months; 3. Inability of patients to actively participate in clinical follow-up; 4. Incapacitated patients; 5. Patients with states of immunodepression; 6. Patients with fibromyalgia; 7. Ongoing systemic inflammatory diseases (stabilized outcomes of such diseases are not considered absolute contraindications); 8. Patients with uncontrolled thyroid metabolic disorders; 9. Patients abusing alcoholic beverages, drugs or medications; 10. Patients who have taken NSAIDs in the 3 days prior to blood collection; 11. Patients with coagulation problems or with ongoing antiplatelet therapy that cannot be suspended for at least 3 days prior to blood draw; 12. Patients with cardiovascular disease for whom a 300-mL blood draw would be contraindicated; 13. Positive serological tests for HBsAg, HCV Ab, HIV-1-2 Ab 14. Other current elbow diseases (osteoarthritis, prevalence of symptomatology due to epitrochleitis, stiff elbow, etc.)