Outcomes of intra-articular injection of sodium hyaluronate for the treatment of osteoarthritis of the knee.

Background: Intra-articular injection of hyaluronic acid has become an intervention step between conservative and operative treatment of knee osteoarthritis. This is recommended by the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR). However, the expected outcomes and the selection criteria are undetermined and controversial.