It is a post-license, multicenter, randomized, single blind, controlled study comparing a single injection of Cingal® (study arm) with a single injection of Monovisc® (control arm).

Inclusion Criteria:

• Age > 18 years of age
• Diagnosed with osteoarthritis of the knee
• Candidate for an intra-articular injection (single joint, unilateral) of Monovisc® or Cingal® as part of their routine clinical care and in accordance with the locally approved label

Exclusion Criteria:

• Previous intra-articular injection within the last 6 months from enrolment
• Known hypersensitivity to cortico-steroids, hyaluronic acid or any component of Cingal® or Monovisc®
• Infectious, traumatic or neoplasic component of knee pathology
• Surgery of the knee within the last 6 months or scheduled surgery in the next two months from enrolment
• Patients with impaired cardio-renal function, endocrine, or other diseases or conditions that use of corticosteroid is warned.
• Patients with known bleeding disorders
• Patient currently treated with oral steroids or opioids
• Patients that, in the investigators' opinion, are unlikely to comply with protocol
• Pregnant or nursing women or women who suspect they might be pregnant.