Patient case (clinical description): A 47-year-old woman comes to the office complaining of pain in the calf and knee when she bends down. The pain limits her activity. Her medical history is significant for osteoarthritis, for which she uses nonsteroidal anti-inflammatory drugs (NSAIDs) for the past two years. She is living with her husband and has 3 children. She doesn't smoke but drinks alcohol occasionally. Her vital signs are normal. On physical examination, there is a small effusion in the right knee. The effusion grew a little larger and she developed a tender swelling in the popliteal fossa and calf. Both the pain and swelling worsened as she bent and straightened her knee.

Patient's own account: I'm a 47-year-old woman, married with 3 kids. I don't smoke and I drink occasionally. I went to the doctor because of pain in my calf and knee when I was bending down. This has been limiting my daily activities. I have been diagnosed with osteoarthritis for which I have taken anti-inflammatory drugs for the past 2 years. The doctor saw a small fluid buildup in my right knee. This buildup became a bit bigger and I have a swollen calf. The pain is worse when I bend and straighten my knee.

Clinical trial: Comparative Evaluation of A-CP HA Kit, Hyaluronic Acid and Placebo for the Treatment of Knee Osteoarthritis

Eligibility criteria:
Inclusion Criteria:

          -  Osteoarthritis grade 2-3 according to the Kellgren & Lawrence grading scale, as
             defined on knee radiographs (less than 3 months old: face view, schuss view, profile
             and patellar axial view at 30°)

          -  Knee Pain level of at least 3 on the 0-10-point WOMAC A subscale

          -  Bilateral osteoarthritis provided that the contralateral knee has a pain no more than
             2 on the 0-10 point scale, and not requiring systemic analgesic treatment except
             paracetamol until the maximum dose of 4g per day

        Exclusion Criteria:

          -  Grade <2 or >3 OA according to the Kellgren and Lawrence grading scale

          -  Bilateral osteoarthritis provided that the contralateral knee has a pain more than 2
             on the 0-10 point scale and requiring systemic analgesic treatment or paracetamol more
             than 4g per day

          -  Viscosupplementation in the treatment site in the past 3 months

          -  Corticosteroid injection in the treatment site in the previous 3 months

          -  Systematic use of corticosteroid (except those that are inhaled) within 3 months

          -  History of allergy to hyaluronic acid

          -  Rheumatological disorders

          -  Clinical evidence of local inflammation such as redness or heat of the joint

          -  Current or medical history of autoimmune disease

          -  Surgery or arthroscopy surgery in the affected knee in the past 3 months

          -  Local infection in the affected knee

          -  Hematologic or clotting disorders (thrombocytopenia) or blood coagulation
             (deficit-blood dyscrasia)

          -  Anaemia (Haemoglobin < 10g/dl)

          -  Platelet count below 150/mmc

          -  Anticoagulant treatment

          -  Viral disease (hepatitis, herpes, varicella, zona, etc.)

          -  Renal failure or hemodialysis

          -  Acute infection

          -  Immunosuppressive states

          -  Malignant disease

          -  Recent fever (within previous 2 weeks) or serious disorders (liver disease, active
             gastroduodenal ulcer, digestive hemorrhage, etc.)

          -  Pregnancy or breastfeeding or planning pregnancy during the course of the study

          -  Immunosuppressants within the past 6 weeks or ongoing

          -  Uncontrolled diabetes

          -  Participation in another clinical study in the past 3 months

          -  Ongoing participation in another OA clinical study

          -  Fracture, skeletal dysplasia, congenital or acquired deformity that affects the knee

          -  Hemoglobin A1C > 8% within 8 weeks prior to the study treatment

          -  Have been given the diagnosis of fibromyalagia, neuropathic pain syndrome, or
             depression

          -  Refusal to sign or inability to give Informed Consent

          -  Inability to understand or comply with the requirements of the study

          -  Any other reason which may interfere with the proper conduct of the study, in the
             investigator's opinion
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 50 Years old.
Subject must be at most 80 Years

Eligibility (NLI label): Contradiction