Inclusion Criteria:  Stated willingness to comply with all study procedures and availability for the duration of the study Male or female, aged ≥ 18 years Clinical diagnosis of knee OA  Exclusion Criteria:  If an active skin disease or infection is present at or near the injection site If the joint is infected or severely inflamed If a degradable intra-articular injectable such as hyaluronic acid is present, it must be expected to be absorbed according to manufacturer's information for the specific product, before injection with Arthrosamid® If the patient has previously received treatment with a different non-absorbable injectable/implant If the patient has received a knee alloplasty or has any foreign material in the knee If the patient has undergone knee arthroscopy within the last 6 months If the patient has haemophilia or is in uncontrolled anticoagulant treatment