The efficacy of intra-articular hyaluronic acid injections on knee osteoarthritis patients

INTERVENTION: Synvisc: Active Comparator Suvenyl: Active Comparator Artz: Active Comparator Topical NSAIDs: Active Comparator CONDITION: Knee osteoarthritis PRIMARY OUTCOME: WOMAC pain, function score SECONDARY OUTCOME: 1. Visual Analog Scale; 2. EQ5D; 3. KOACAD parameter on plain knee radiograph INCLUSION CRITERIA: 1. Males and females 40 to 80 years of age. 2. The ACR Criteria for osteoarthritis of the knee. 3. Radiographic evidence of OA, Kellgren and Lawrence grade 1 to 3 on prior X‐rays at screening. Only the tibio‐femoral joint will be evaluated. 4. Chronic pain for at least 1 month prior to study entry (WOMAC pain score)