The aim of present study is to to investigate whether the combined injection of HA and CS was superior than HA alone in the treatment of knee OA.

Intra-articular injection of hyaluronic acid (HA) or corticosteroids (CS) has been widely used with debate on its efficacy in osteoarthritis (OA). The aim of present study is to to investigate whether the combined injection of HA and CS is superior than HA alone in the treatment of knee OA.

Inclusion Criteria:

According to radiographic findings, patients who are suffering from knee OA for over 3 months have to be stage II-IV according to the Kellgren-Lawrence (KL) grade by a senior radiologist. The diagnosis of symptomatic knee OA is based on American Rheumatism Association classification criteria for knee osteoarthritis.

Exclusion Criteria:

Exclusion criteria are the diagnosis of rheumatoid arthritis or other inflammatory OA, presence of trauma or pain-causing diseases, treatment with oral medications in recent 3 days, physiotherapy and intra-articular injection of HA or CS in the past 6 months. Participants who are allergic to any of the medications used in this study or diagnosed with current systemic infection are also excluded.