Patient case (clinical description): A 17-year-old male comes to the office due to several months of right elbow pain.  The pain is worse with activity and limits his workouts and activities.  He has tried over-the-counter medications with limited relief.  Medical history is notable for eczema, and current medications include a topical hydrocortisone ointment.  He is sexually active with his girlfriend and uses condoms. He does not smoke or drink alcohol. He plays tennis most of the days of the week. The comprehensive evaluation shows pain on the lateral side of the elbow, made worse by pressure applied on the lateral epicondyle of the humerus and when making a fist with the elbow joint straightened. The patient has this pain since last year and had several courses of physical therapy.

Patient's own account: I'm 17, and I had to go to the doctor because I've been suffering from my right elbow for several months. The pain is even worse when I do sports and it kind of limits me for my workouts and activities. I tried over-the-counter medications but it didn't work much. I had eczema before and my medication is ointments that contain cortisone. I am sexually active as a 17-year-old guy, and I have a girlfriend, and we use condoms. I don't smoke or drink. I play tennis most days of the week. I did an exam that showed pain on the side of my elbow and it was worse when they applied some pressure on it and when I was putting my hand as a fist. I have had this pain since last year, and I had several sessions of physical therapy already.

Clinical trial: Bundang Rehabilitative Impact Study of the Elbow Epicondylitis

Eligibility criteria:
Inclusion Criteria:

        The inclusion criteria for the study are

          -  provision of informed consent by patient

          -  adult men or women aged > 18 and < 65 years

          -  Patients had a clinical diagnosis of lateral epicondylitis based on local tenderness
             to palpation at lateral epicondyle and pain in that area elicited with active
             extension of the wrist in pronation and elbow extension

          -  History of pain >3 months and <2 years, failed each of the following conservative care
             modalities: relative rest, physical/occupational therapy, non-steroidal
             anti-inflammatorydrugs and two corticosteroid injections.

          -  Baseline elbow pain > 50 mm/100 mm using a visual analog scale (VAS) with resisted
             active extension of the wrist in pronation and elbow extension

          -  All affected elbows were screened with radiography and all proved to be normal, except
             for some calcifications of the common extensor origin.

          -  documented sonographic diagnosis of common extensor tendinosis was based on tendon
             echogenicity, loss of the normal echotexture and tendon thickening. We also performed
             the sonographic assessment of the extensor carpi radialis brevis, extensor digitorum
             communis and radial collateral ligament; tendinosis defined as ill- or well-defined
             focal/generalized hypoechogenic swollen tendon with loss of normal fibrillary pattern
             and focal tear defined as well-defined anechoic cleft

        Exclusion Criteria:

          -  History of narcotic use for pain management > 1 mo, narcotic abuse

          -  History of alcoholic abuse

          -  any recent febrile or infectious disease

          -  corticosteroid injection within the past 3 months

          -  Signs of other causes for lateral elbow pain (posterior interosseous nerve entrapment,
             fracture or osteochondral lesion)

          -  History of carpal tunnel syndrome, cervical radiculopathy or neurologic disorder

          -  Other chronic widespread pain syndromes

          -  History of bleeding disorder, anemia

          -  Systemic disorders such as diabetes, rheumatoid arthritis,or hepatitis

          -  Intolerance/allergy to local anesthetics or injection corticosteroids

          -  history of vasovagal shock

          -  Pregnancy/lactation

          -  history of any malignancy (including hematologic and non hematologic malignancies)

          -  Hypotension, systolic BP <100mmHg, diastolic BP < 60mmHg

          -  Systemic disorders such as diabetes, rheumatoid arthritis, or hepatitis, nephropathy,
             Hypothyroidism.

          -  History of receiving a PDRN injection at any site

          -  Allergic reaction or hypersensitivity for PDRN

          -  Workers compensation or worker using both upper extremities, especially elbow and hand
             for most labor activity

          -  history of acute elbow trauma (<1 week)

          -  patients requiring antiplatelet medications for the treatment of heart attack, stroke,
             or other medical condition

          -  Previous surgery for elbow tendinosis or other disease at affected side

          -  Active bilateral elbow tendinosis within 4 weeks before randomization

          -  Tendon echogenicity, grade 0 and 4 were excluded; The degree of tendinosis is grade
             based on changes in tendon echotexture at sonographic assessment, Diagnostic
             ultrasound features for the RISEe
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 19 Years old.
Subject must be at most 64 Years

Eligibility (NLI label): Contradiction