Efficacy of Intra-articular Injection of Human Amniotic Suspension Allograft and Platelet-rich Plasma in the Treatment of Knee Osteoarthritis.

Inclusion Criteria: * Age between 20 and 80 years * Ability to provide informed consent * Unilateral or bilateral knee VAS pain score ≥ 4 of 10 (worst possible pain) for more than 4 months * Diagnosis of OA Kellgren-Lawrence I-III by radiography (triple-film of bilateral lower limb, standard knee anterior-posterior view in full extension, lateral view in 30-degrees flexion, and 45°Merchant views) * No prior PRP injection of knee * No prior surgical procedure of the participating knee * BMI\<40 kg/m2 Exclusion Criteria: * Lawrence stage IV * Major axial deviation (varus\> 5°, valgus \> 5°) * Any concomitant symptomatic knee disorder (i.e. ligamentous/ meniscal injury) * Systemic inflammatory arthropathy * Hematologic diseases * Severe cardiovascular disease * Neurological disorders * Active infection * Immuno-compromised * Therapy with anticoagulants or antiaggregants * Use of NSAIDs and/or chondroprotective supplements, such as glucosamines and chondroitin sulfates, within 7 days prior to trial * Recent intra-articular injection of corticosteroids (within 30 days) * Prior treatment with HA in past 6 monthsHb\< 11 g/dL * Platelet count \< 150,000/mm3